Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
STAMP DEVICE FOR PRINTING TIME
Document Type and Number:
WIPO Patent Application WO/2021/019560
Kind Code:
A1
Abstract:
The present disclosure relates to stamp device (100A, 100B, 200A) and stamping system (200) that prints time alongside date. Stamp device (100A, 100B, 200A) includes printing box (102A, 102B, 202) having plurality of wheels (114A, 114B, 212) to print time and date. Wheels (114A, 114B, 212) are provided with grooves (402B, 404B, 406B, 408B) and ratchets (402A, 404A, 406A, 408A, 410A) disposed on side surfaces of each of wheels (114A, 114B, 212). Wheels (114A, 114B, 212) have predefined number of grooves (402B, 404B, 406B, 408B). Wheels (114A, 114B, 212) are interconnected by linkage including actuating pawl (106A, 106B, 218), which has teeth (108-1A to 108-5A, 108-1B to 108-5B) that engage with ratchets (402A, 404A, 406A, 408A, 410A). The teeth (108-1A to 108-5A, 108-1B to 108-5B) enter into grooves (402B, 404B, 406B, 408B) according to pre-defined sequences.

Inventors:
TARASANKAR SAMANTA (IN)
Application Number:
PCT/IN2020/050650
Publication Date:
February 04, 2021
Filing Date:
July 27, 2020
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
TARASANKAR SAMANTA (IN)
International Classes:
G01R33/07; B41F13/00; B41F33/00; B41J7/96; B41K3/10; B41K3/12; G01R33/00
Foreign References:
DE854442C1952-11-04
US20100128072A12010-05-27
US3072047A1963-01-08
Attorney, Agent or Firm:
LAKSHMIKUMARAN, Malathi et al. (IN)
Download PDF:
Claims:
I claim:

1 . A stamp device (100A, 100B) comprising:

a printing box (102A, 102B) including a plurality of wheels (1 14A, 1 14B) to print time information, wherein on a periphery of each wheel of the plurality of wheels (1 14A, 1 14B), a set of characters are engraved, and wherein the plurality of wheels (1 14A, 1 14B) comprises:

a set of time-printing wheels including a unit-place minute wheel (402), a tens-place minute wheel (404), a unit-place hour wheel (406), and a tens-place hour wheel (408);

a linkage coupled with the plurality of wheels (1 14A, 1 14B), the linkage comprising:

an actuating pawl (106A, 106B) including one or more teeth (108- 1 A to 108-5A, 108-1 B to 108-5B);

a plurality of ratchets (402A, 404A, 406A, 408A, 410A), wherein a set of ratchets, from amongst the plurality of ratchets (402A, 404A, 406A, 408A, 410A), is disposed on a side surface of each wheel of the plurality of wheels (1 14A, 1 14B); and

a plurality of grooves (402B, 404B, 406B, 408B), wherein at least one groove (402B) from the plurality of grooves (402B, 404B, 406B, 408B) is disposed on the side surface of the unit-place minute wheel (402), at least two grooves (404B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the tens-place minute wheel (404), and at least two grooves (406B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the unit-place hour wheel (406);

a lever (104A, 104B) connected to the linkage to actuate the actuating pawl (106A, 106B) to enable a rotation of at least one wheel of the plurality of wheels (1 14A, 1 14B); and

a power device connected to the lever (104A, 104B) to move the lever (104A, 104B), wherein, upon actuation by the lever (104A, 104B), at least one tooth of the actuating pawl (106A, 106B) is to engage with at least one ratchet of the plurality of ratchets (402A, 404A, 406A, 408A, 410A) to enable the rotation of a corresponding wheel of the plurality of wheels (1 14A, 1 14B), and wherein the at least one tooth is to enter into at least one corresponding groove upon the rotation of the corresponding wheel by a predefined degree.

2. The stamp device (100A, 100B) as claimed in claim 1 , the set of characters being engraved on the periphery of each wheel of the plurality of wheels (1 14A, 1 14B) in a pre-defined sequence, wherein a completion of the pre-defined sequence defines a changeover position of each wheel of the plurality of wheels (1 14A, 1 14B), wherein the at least one tooth enters into the at least one corresponding groove of the at least one wheel of the plurality of wheels (114A, 1 14B) upon reaching the changeover position. 3. The stamp device (100A, 100B) as claimed in claim 1 , wherein the at least one tooth involved in the rotation of the unit-place minute wheel (402) is to enter into the at least one corresponding groove (402B) of the unit- place minute wheel (402) upon the unit-place minute wheel (402) reaching a first changeover position pertaining to the unit-place minute wheel (402), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place minute wheel (402), into the at least one corresponding groove (402B), the at least one tooth involved in the rotation of the tens-place minute wheel (404), is to engage with the at least one ratchet (404A) of the tens-place minute wheel (404).

4. The stamp device (100A, 100B) as claimed in claim 1 , wherein the at least one tooth involved in the rotation of the tens-place minute wheel (404) is to enter into one groove (404B) of the tens-place minute wheel (404) upon the tens-place minute wheel (404) reaching a second changeover position pertaining to the tens-place minute wheel (404), and wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place minute wheel (404), into the at least one corresponding groove (404B), the at least one tooth involved in the rotation of the unit-place hour wheel (406), is to engage with the at least one ratchet (406A) of the unit-place hour wheel (406).

5. The stamp device (100A, 100B) as claimed in claim 1 , wherein the at least one tooth involved in the rotation of the unit-place hour wheel (406) is to enter into one groove (406B) of the unit-place hour wheel (406) upon the unit-place hour wheel (406) reaching a third changeover position pertaining to the unit-place hour wheel (406), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place hour wheel (406), into the at least one corresponding groove (406B), the at least one tooth involved in the rotation of the tens-place hour wheel (408), is to engage with the at least one ratchet (408A) of the tens-place hour wheel (408).

6. The stamp device (100A, 100B) as claimed in claim 1 , wherein the set of time-printing wheels includes an AM/PM wheel (410), and at least six grooves (408B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the tens-place hour wheel (408). 7. The stamp device (100A, 100B) as claimed in claim 6, wherein the at least one tooth involved in the rotation of the tens-place hour wheel (408) is to enter into one groove (408B) of the tens-place hour wheel (408) upon the tens-place hour wheel (408) reaching a fourth changeover position pertaining to the tens-place hour wheel (408), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place hour wheel (408), into the at least one corresponding groove (408B), the at least one tooth involved in the rotation of the AM/PM wheel (410), is to engage with the at least one ratchet (410A) of the AM/PM wheel (410).

8. The stamp device (1 OOA, 100B) as claimed in claim 1 , wherein the set of characters includes at least one of numeric digits and alphabets.

9. The stamp device (100A, 100B) as claimed in claim 1 , wherein the periphery of each wheel of the plurality of wheels (114A, 1 14B) is engraved with a set of twelve characters.

10. The stamp device (100A, 100B) as claimed in claim 1 , wherein the plurality of wheels (1 14B) includes a set of date-printing wheels to print date information, the set of date-printing wheels including at least two year- wheels, at least one month-wheel, and two day-wheels. 1 1. The stamp device (100A, 100B) as claimed in claim 10, wherein the periphery of each wheel of the plurality of wheels (1 14B) is engraved with a set of at least ten characters.

12. The stamp device (100A, 100B) as claimed in claim 1 , wherein the stamp device (100A, 100B) comprises a plurality of retaining pawls disposed on the printing box (102A, 102B) in a spring-loaded manner, wherein a retaining pawl of the plurality of retaining pawls is to engage with a ratchet of the plurality of ratchets (402A, 404A, 406A, 408A, 410A) to limit one of a reverse rotation and an over rotation of a corresponding wheel of the plurality of wheels (1 14A, 1 14B). 13. The stamp device (100A, 100B) as claimed in claim 1 , wherein the power device is one of an alternating current (AC) motor and a direct current (DC) motor.

14. The stamp device (100A, 100B) as claimed in claim 1 , wherein the power device is a stepper motor. 15. The stamp device (100A, 100B) as claimed in claim 1 , wherein the power device is connected to a cam, and wherein the cam is to actuate an indexing of the lever (104A, 104B).

16. The stamp device (100A, 100B) as claimed in claim 1 , wherein the rotation of at least one wheel of the plurality of wheels (1 14A, 1 14B) is actuated in conjunction with an indexing of the lever (104A, 104B).

17. The stamp device (100A, 100B) as claimed in claim 1 , the stamp device (100A, 100B) comprising:

a casing (1 10A, 1 10B) to enclose the printing box (102A, 102B), wherein the casing (1 10A, 1 10B) includes a plurality of side walls, and wherein a circular slot is formed through first and second side walls of the plurality of side walls, the first and the second side walls being at opposite faces of the casing (1 10A, 1 10B); and

a crank housing (1 12A, 1 12B) placed within the casing (1 10A, 1 10B), wherein the crank housing (1 12A, 1 12B) comprises:

a shaft, wherein the circular slot is formed axially through the crank housing (1 12A, 1 12B) and the shaft is axially disposed within the crank housing (1 12A, 1 12B), and wherein the plurality of wheels (1 14A, 1 14B) is mounted on the shaft, and

a crank element including the actuating pawl (106A, 106B).

18. The stamp device (100A, 100B) as claimed in claim 2, where the at least one groove (402B, 404B, 406B, 408B) of the at least one wheel of the plurality of wheels (1 14A, 1 14B) is disposed at the changeover position of each wheel.

19. A stamping system (200) comprising:

a stamp device (200A) comprising:

a printing box (202) including a plurality of wheels (212) to print time information, wherein on a periphery of each wheel of the plurality of wheels (212), a set of characters are engraved, and wherein the plurality of wheels (212) comprises:

a set of time-printing wheels including a unit-place minute wheel 402, a tens-place minute wheel 404, a unit-place hour wheel 406, and a tens-place hour wheel (408); and a plurality of magnets, wherein a set of magnets, from amongst the plurality of magnets, is disposed between at least two characters engraved on each wheel of the plurality of wheels (212);

at least one indicator (210) disposed on the printing box (202); a linkage coupled with the plurality of wheels (212), the linkage comprising:

a plurality of magnetic field sensors, wherein a set of magnetic field sensors, from amongst the plurality of magnetic field sensors, is disposed in a stationary position besides each wheel of the plurality of wheels (212) to determine a magnetic orientation of the set of magnets;

an actuating pawl (218) including one or more teeth;

a plurality of ratchets (402A, 404A, 406A, 408A, 410A), wherein a set of ratchets, from amongst the plurality of ratchets (402A, 404A, 406A, 408A, 410A), is disposed on a side surface of each wheel of the plurality of wheels (212); and

a plurality of grooves (402B, 404B, 406B, 408B), wherein at least one groove (402B) from the plurality of grooves (402B, 404B, 406B, 408B) is disposed on the side surface of the unit- place minute wheel (402), at least two grooves (404B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the tens-place minute wheel (404), and at least two grooves (406B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the unit- place hour wheel (406);

a lever (208) connected to the linkage to actuate the actuating pawl (218) to enable a rotation of at least one wheel of the plurality of wheels (212), and

a power device connected to the lever (208) to move the lever (208), and wherein, upon actuation by the lever (208), at least one tooth of the actuating pawl (218) is to engage with at least one ratchet of the plurality of ratchets (402A, 404A, 406A, 408A, 410A) to enable the rotation of a corresponding wheel of the plurality of wheels (212), and wherein the at least one tooth is to enter into at least one corresponding groove (402B, 404B, 406B, 408B) upon rotation of the corresponding wheel by a predetermined degree; and

a controller (204) communicatively coupled to the printing box (202), wherein the controller (204) is to transmit a control signal to the power device to move the lever (208). 20. The stamping system (200) as claimed in claim 19, the set of characters being engraved on the periphery of each wheel of the plurality of wheels (212) in a pre-defined sequence, wherein a completion of the pre defined sequence defines a changeover position of each wheel of the plurality of wheels (212), wherein the at least one tooth enters into the at least one corresponding groove of the at least one wheel of the plurality of wheels (212) upon reaching the changeover position.

21. The stamping system (200) as claimed in claim 19, wherein the at least one tooth involved in the rotation of the unit-place minute wheel (402) is to enter into the at least one groove (402B) of the unit-place minute wheel (402) upon the unit-place minute wheel (402) reaching a first changeover position pertaining to the unit-place minute wheel (402), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place minute wheel (402), into the at least one corresponding groove (402B), the at least one tooth involved in the rotation of the tens-place minute wheel 404, is to engage with the at least one ratchet (404A) of the tens-place minute wheel 404.

22. The stamping system (200) as claimed in claim 19, wherein the at least one tooth involved in the rotation of the tens-place minute wheel (404) is to enter into one groove (404B) of the tens-place minute wheel (404) upon the tens-place minute wheel (404) reaching a second changeover position pertaining to the tens-place minute wheel (404), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place minute wheel (404), into the at least one corresponding groove (404B), the at least one tooth involved in the rotation of the unit-place hour wheel (406), is to engage with the at least one ratchet (406A) of the unit-place hour wheel (406).

23. The stamping system (200) as claimed in claim 19, wherein the at least one tooth involved in the rotation of the unit-place hour wheel (406) is to enter into one groove (406B) of the unit-place hour wheel (406) upon the unit-place hour wheel (406) reaching a third changeover position pertaining to the unit-place hour wheel (406), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place hour wheel (406), into the at least one corresponding groove (406B), the at least one tooth involved in the rotation of the tens-place hour wheel (408), is to engage with the at least one ratchet (408A) of the tens-place hour wheel (408).

24. The stamping system (200) as claimed in claim 19, wherein the set of time-printing wheels includes an AM/PM-wheel (410), and at least six grooves (408B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the tens-place hour wheel (408).

25. The stamping system (200) as claimed in claim 24, wherein the at least one tooth involved in the rotation of the tens-place hour wheel (408) is to enter into one groove (408B) of the tens-place hour wheel (408) upon the tens-place hour wheel (408) reaching a fourth changeover position pertaining to the tens-place hour wheel (408), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place hour wheel (408), into the at least one corresponding groove (408B), the at least one tooth involved in the rotation of the AM/PM wheel (410), is to engage with the at least one ratchet (410A) of the AM/PM wheel (410).

26. The stamping system (200) as claimed in claim 19, wherein the set of characters includes at least one of numeric digits and alphabets. 27. The stamping system (200) as claimed in claim 19, wherein the periphery of each wheel of the plurality of wheels (1 14A, 114B, 212) is engraved with a set of twelve characters.

28. The stamping system (200) as claimed in claim 19, wherein the plurality of wheels (212) includes a set of date-printing wheels to print date information, the set of date-printing wheels including at least two year- wheels, at least one month-wheel, and two day-wheels.

29. The stamping system (200) as claimed in claim 19, wherein the periphery of each wheel of the plurality of wheels (212) is engraved with a set of at least ten characters. 30. The stamping system (200) as claimed in claim 19, wherein the set of magnetic field sensors is to communicate the determined magnetic orientation of the set of magnets, to the controller (204), and wherein the controller (204) is to detect a current set of characters, based on the determination result, wherein the current set of characters are the characters of the at least one wheel of the plurality of wheels (212) facing towards a to-be printed target.

31. The stamping system (200) as claimed in claim 30, wherein the controller (204) is to:

monitor the current set of characters of the plurality of wheels (21 2) ; obtain a current time information ;

match the monitored current set of characters with the current time information; and

output the matching result via the at least one indicator (210).

32. The stamping system (200) as claimed in claim 31 , wherein the stamping system (200) comprises a real-time chip (RTC) coupled to the controller (204), and wherein the controller (204) obtains the current time information from the RTC. 33. The stamping system (200) as claimed in claim 32, the stamping system (200) includes a plurality of buttons, coupled to the controller (204), to allow a user to enter the current time information into the controller (204).

34. The stamping system (200) as claimed in claim 31 , the stamping system (200) comprising:

a first display (214) to display the current set of characters of the plurality of wheels (212); and

a second display (21 6) to display the current time information.

35. The stamping system (200) as claimed in claim 19, wherein the controller (204) is communicatively coupled to the printing box (202) via a network (206).

36. The stamping system (200) as claimed in claim 19, wherein the set of magnetic field sensors are Hall Effect sensors.

37. The stamping system (200) as claimed in claim 19, wherein the at least one indicator (210) is light-emitting diode (LED). 38. A method of operation of a stamping system (200) as claimed in one of claims 19 to 37, the method comprising:

determining, by a set of magnetic field sensors, a magnetic orientation of a set of magnets disposed on each wheel of a plurality of wheels (21 2) of the printing box (202), wherein the plurality of wheels (21 2) includes a plurality of printing faces, wherein a set of printing faces from the plurality of printing faces are disposed on a periphery of each wheel of the plurality of wheels (21 2) and at least one printing face of the set of printing face includes a character; communicating the determined magnetic orientation to a controller (204);

determining, by the controller (204), an orientation of each wheel from a plurality of wheels (212) of the printing box (202), based on the determined magnetic orientation;

determining, by the controller (204), a current set of characters, based on the determined orientation of each wheel, wherein the current set of characters are the characters of the at least one wheel of the plurality of wheels (212) facing towards a to-be printed target;

determining, by the controller (204), whether the current set of characters of a plurality of wheels (212), match with a current time information obtained from a real-time chip (RTC);

upon determining a mis-match between the current set of characters and the current time information of the RTC:

in a manual mode, deactivating a power device and indicating, by the controller (204) and via at least one indicator (210), an operator for manual setting of the plurality of wheels (212) to match the current set of characters with the current time information; or

in a non-manual mode, indexing a lever (208) of a stamp device (200A) of the stamping system (200) using the power device to match the current set of characters with the current time information; and

upon determining a match between the current set of characters and the current time information of the RTC, indicating, by the controller (204) and via the at least one indicator (210), a ready-to-use state of the stamping system (200) to the operator.

39. The method as claimed in claim 38, wherein the method comprises, upon determining the match between the current set of characters and the current time information of the RTC: resetting a face checking counter (FCC), provided in a memory coupled to the controller (204), wherein the FCC counts and stores a value of every minute-increment for which the match between the current set of characters and the current time information is not performed;

resetting a delay time counter (DTC), provided in the memory, wherein the DTC counts and stores a number of occurrence of a delay in rotation of the at least one wheel of the plurality of wheels (212);

loading the matched time information in a printing face tracking counter, wherein the printing face tracking counter is provided in the memory to store a value of the current set of characters; and

updating the printing face tracking counter for every indexing of the lever (208) to update the current set of characters.

40. The method as claimed in claim 39, wherein the method comprises, upon determining the match between the current set of characters and the current time information of the RTC:

determining whether the stamping system (200) is in an idle mode or an active mode;

upon determining that the stamping system (200) is in active mode: updating the values of the DTC and the FCC with every minute- increment of the RTC and deactivating the power device; and

comparing the value of the DTC with a predetermined tolerance value to determine whether the value of the DTC is greater than the predetermined tolerance value;

upon determining that the value of DTC is greater than the predetermined tolerance value, keeping the stamping system (200) in an ON state by an operator for updating a current time; and

upon determining that the value of DTC is one of less than or equal to the predetermined tolerance value, repeating the determination of whether the stamping system (200) is in idle mode or the active mode; and

upon determining that the stamping is in idle mode:

determining whether the value of the DTC is one of less than or equal to zero;

upon determining that the value of the DTC is greater than zero:

performing at least one of incrementing the values of the DTC and the FCC for every minute increment of the RTC and decrementing the value of the DTC after every indexing of the lever (208) of the printing box (202) through the power device;

upon decrementing the value of the DTC, updating the printing face tracking counter and updating the first display (214) of the stamping system (200) with an updated current set of characters of the plurality of wheels (212); and

repeating the determination of whether the stamping system (200) is in the idle mode or the active mode; and upon determining that the value of the DTC is one of less than and equal to zero, comparing the value of the FCC with a set time interval;

upon determining that the value of the FCC is greater than the set time interval:

determining whether a timer of the RTC is to be updated;

upon determining that the timer of the RTC is to be updated, receiving user input for updating the timer via a keyboard of the stamping system (200) and repeating the determination of whether the current set of characters match with the current time information; and upon determining that the timer of the RTC is not to be updated, repeating the determination of whether the current set of characters match with the current time information as claim in claim 38;

upon determining that the value of the FCC is one of less than and equal to the set time interval, incrementing the value of the FCC and the DTC for every minute increment of the RTC; and

repeating the indicating of the ready-to-use state of the stamping system (200) to the operator as claimed in claim 38.

41. The method as claimed in claim 38, wherein the method comprises: displaying the current set of characters on a first display (214); and displaying the current time information on a second display (216). 42. The method as claimed in claim 39, where the value of the FCC is updated for increment of every minute of the RTC, and the value of the DTC is updated for storing a number of pending rotations of the at least one wheel of the plurality of wheels (212).

AMENDED CLAIMS

received by the International Bureau on 14 January 2021 (14.01 .2021 ).

I claim:

1 . A stamp device (100A, 100B) comprising:

a printing box (102A, 102B) including a plurality of wheels (1 14A, 1 14B) to print time information, wherein on a periphery of each wheel of the plurality of wheels (1 14A, 1 14B), a set of characters are engraved, and wherein the plurality of wheels (1 14A, 1 14B) comprises:

a set of time-printing wheels including a unit-place minute wheel (402), a tens-place minute wheel (404), a unit-place hour wheel (406), and a tens-place hour wheel (408);

a linkage coupled with the plurality of wheels (1 14A, 1 14B), the linkage comprising:

an actuating pawl (106A, 106B) including one or more teeth (108- 1 A to 108-5A, 108-1 B to 108-5B);

a plurality of ratchets (402A, 404A, 406A, 408A, 410A), wherein a set of ratchets, from amongst the plurality of ratchets (402A, 404A, 406A, 408A, 410A), is disposed on a side surface of each wheel of the plurality of wheels (1 14A, 1 14B); and

a plurality of grooves (402B, 404B, 406B, 408B), wherein at least one groove (402B) from the plurality of grooves (402B, 404B, 406B, 408B) is disposed on the side surface of the unit-place minute wheel (402), at least two grooves (404B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the tens-place minute wheel (404), and at least two grooves (406B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the unit-place hour wheel (406);

a lever (104A, 104B) connected to the linkage to actuate the actuating pawl (106A, 106B) to enable a rotation of at least one wheel of the plurality of wheels (1 14A, 1 14B); and

a power device connected to the lever (104A, 104B) to move the lever (104A, 104B), wherein the power device is one of an alternating current (AC) motor and a direct current (DC) motor, and wherein, upon actuation by the lever (104A, 104B), at least one tooth of the actuating pawl (106A, 106B) is to engage with at least one ratchet of the plurality of ratchets (402A, 404A, 406A, 408A, 410A) to enable the rotation of a corresponding wheel of the plurality of wheels (1 14A, 1 14B), and wherein the at least one tooth is to enter into at least one corresponding groove upon the rotation of the corresponding wheel by a predefined degree.

2. The stamp device (100A, 100B) as claimed in claim 1 , the set of characters being engraved on the periphery of each wheel of the plurality of wheels (1 14A, 1 14B) in a pre-defined sequence, wherein a completion of the pre-defined sequence defines a changeover position of each wheel of the plurality of wheels (1 14A, 114B), wherein the at least one tooth enters into the at least one corresponding groove of the at least one wheel of the plurality of wheels (1 14A, 1 14B) upon reaching the changeover position. 3. The stamp device (100A, 100B) as claimed in claim 1 , wherein the at least one tooth involved in the rotation of the unit-place minute wheel (402) is to enter into the at least one corresponding groove (402B) of the unit- place minute wheel (402) upon the unit-place minute wheel (402) reaching a first changeover position pertaining to the unit-place minute wheel (402), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place minute wheel (402), into the at least one corresponding groove (402B), the at least one tooth involved in the rotation of the tens-place minute wheel (404), is to engage with the at least one ratchet (404A) of the tens-place minute wheel (404).

4. The stamp device (100A, 100B) as claimed in claim 1 , wherein the at least one tooth involved in the rotation of the tens-place minute wheel (404) is to enter into one groove (404B) of the tens-place minute wheel (404) upon the tens-place minute wheel (404) reaching a second changeover position pertaining to the tens-place minute wheel (404), and wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place minute wheel (404), into the at least one corresponding groove (404B), the at least one tooth involved in the rotation of the unit-place hour wheel (406), is to engage with the at least one ratchet (406A) of the unit-place hour wheel (406).

5. The stamp device (100A, 100B) as claimed in claim 1 , wherein the at least one tooth involved in the rotation of the unit-place hour wheel (406) is to enter into one groove (406B) of the unit-place hour wheel (406) upon the unit-place hour wheel (406) reaching a third changeover position pertaining to the unit-place hour wheel (406), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place hour wheel (406), into the at least one corresponding groove (406B), the at least one tooth involved in the rotation of the tens-place hour wheel (408), is to engage with the at least one ratchet (408A) of the tens-place hour wheel (408).

6. The stamp device (100A, 100B) as claimed in claim 1 , wherein the set of time-printing wheels includes an AM/PM wheel (410), and at least six grooves (408B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the tens-place hour wheel (408). 7. The stamp device (100A, 100B) as claimed in claim 6, wherein the at least one tooth involved in the rotation of the tens-place hour wheel (408) is to enter into one groove (408B) of the tens-place hour wheel (408) upon the tens-place hour wheel (408) reaching a fourth changeover position pertaining to the tens-place hour wheel (408), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place hour wheel (408), into the at least one corresponding groove (408B), the at least one tooth involved in the rotation of the AM/PM wheel (410), is to engage with the at least one ratchet (410A) of the AM/PM wheel (410).

8. The stamp device (1 OOA, 100B) as claimed in claim 1 , wherein the set of characters includes at least one of numeric digits and alphabets.

9. The stamp device (100A, 100B) as claimed in claim 1 , wherein the periphery of each wheel of the plurality of wheels (114A, 114B) is engraved with a set of twelve characters.

10. The stamp device (100A, 100B) as claimed in claim 1 , wherein the plurality of wheels (1 14B) includes a set of date-printing wheels to print date information, the set of date-printing wheels including at least two year- wheels, at least one month-wheel, and two day-wheels. 1 1. The stamp device (100A, 100B) as claimed in claim 10, wherein the periphery of each wheel of the plurality of wheels (1 14B) is engraved with a set of at least ten characters.

12. The stamp device (100A, 100B) as claimed in claim 1 , wherein the stamp device (100A, 100B) comprises a plurality of retaining pawls disposed on the printing box (102A, 102B) in a spring-loaded manner, wherein a retaining pawl of the plurality of retaining pawls is to engage with a ratchet of the plurality of ratchets (402A, 404A, 406A, 408A, 410A) to limit one of a reverse rotation and an over rotation of a corresponding wheel of the plurality of wheels (1 14A, 114B). 13. The stamp device (100A, 100B) as claimed in claim 1 , wherein the power device is a stepper motor.

14. The stamp device (100A, 100B) as claimed in claim 1 , wherein the power device is connected to a cam, and wherein the cam is to actuate an indexing of the lever (104A, 104B). 15. The stamp device (100A, 100B) as claimed in claim 1 , wherein the rotation of at least one wheel of the plurality of wheels (1 14A, 114B) is actuated in conjunction with an indexing of the lever (104A, 104B).

16. The stamp device (1 OOA, 10OB) as claimed in claim 1 , the stamp device (100A, 100B) comprising:

a casing (1 10A, 1 1 OB) to enclose the printing box (102A, 102B), wherein the casing (1 10A, 1 1 OB) includes a plurality of side walls, and wherein a circular slot is formed through first and second side walls of the plurality of side walls, the first and the second side walls being at opposite faces of the casing (1 10A, 1 1 OB); and

a crank housing (1 12A, 1 12B) placed within the casing (1 10A, 1 1 OB), wherein the crank housing (1 12A, 1 12B) comprises:

a shaft, wherein the circular slot is formed axially through the crank housing (1 12A, 1 12B) and the shaft is axially disposed within the crank housing (1 12A, 1 12B), and wherein the plurality of wheels (1 14A, 1 14B) is mounted on the shaft, and

a crank element including the actuating pawl (106A, 106B).

17. The stamp device (1 OOA, 100B) as claimed in claim 2, where the at least one groove (402B, 404B, 406B, 408B) of the at least one wheel of the plurality of wheels (1 14A, 1 14B) is disposed at the changeover position of each wheel.

18. A stamping system (200) comprising:

a stamp device (200A) comprising:

a printing box (202) including a plurality of wheels (212) to print time information, wherein on a periphery of each wheel of the plurality of wheels (212), a set of characters are engraved, and wherein the plurality of wheels (212) comprises:

a set of time-printing wheels including a unit-place minute wheel 402, a tens-place minute wheel 404, a unit-place hour wheel 406, and a tens-place hour wheel (408); and

a plurality of magnets, wherein a set of magnets, from amongst the plurality of magnets, is disposed between at least two characters engraved on each wheel of the plurality of wheels (212);

at least one indicator (210) disposed on the printing box (202); a linkage coupled with the plurality of wheels (212), the linkage comprising:

a plurality of magnetic field sensors, wherein a set of magnetic field sensors, from amongst the plurality of magnetic field sensors, is disposed in a stationary position besides each wheel of the plurality of wheels (212) to determine a magnetic orientation of the set of magnets;

an actuating pawl (218) including one or more teeth;

a plurality of ratchets (402A, 404A, 406A, 408A, 410A), wherein a set of ratchets, from amongst the plurality of ratchets (402A, 404A, 406A, 408A, 410A), is disposed on a side surface of each wheel of the plurality of wheels (212); and

a plurality of grooves (402B, 404B, 406B, 408B), wherein at least one groove (402B) from the plurality of grooves (402B, 404B, 406B, 408B) is disposed on the side surface of the unit- place minute wheel (402), at least two grooves (404B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the tens-place minute wheel (404), and at least two grooves (406B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the unit- place hour wheel (406);

a lever (208) connected to the linkage to actuate the actuating pawl (218) to enable a rotation of at least one wheel of the plurality of wheels (212), and

a power device connected to the lever (208) to move the lever (208), wherein the power device is one of an alternating current (AC) motor and a direct current (DC) motor, and wherein, upon actuation by the lever (208), at least one tooth of the actuating pawl (218) is to engage with at least one ratchet of the plurality of ratchets (402A, 404A, 406A, 408A, 410A) to enable the rotation of a corresponding wheel of the plurality of wheels (212), and wherein the at least one tooth is to enter into at least one corresponding groove (402B, 404B, 406B, 408B) upon rotation of the corresponding wheel by a predetermined degree; and

a controller (204) communicatively coupled to the printing box (202), wherein the controller (204) is to transmit a control signal to the power device to move the lever (208). 19. The stamping system (200) as claimed in claim 18, the set of characters being engraved on the periphery of each wheel of the plurality of wheels (212) in a pre-defined sequence, wherein a completion of the pre-defined sequence defines a changeover position of each wheel of the plurality of wheels (212), wherein the at least one tooth enters into the at least one corresponding groove of the at least one wheel of the plurality of wheels (212) upon reaching the changeover position.

20. The stamping system (200) as claimed in claim 18, wherein the at least one tooth involved in the rotation of the unit-place minute wheel (402) is to enter into the at least one groove (402B) of the unit-place minute wheel (402) upon the unit-place minute wheel (402) reaching a first changeover position pertaining to the unit-place minute wheel (402), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place minute wheel (402), into the at least one corresponding groove (402B), the at least one tooth involved in the rotation of the tens-place minute wheel 404, is to engage with the at least one ratchet (404A) of the tens-place minute wheel 404.

21. The stamping system (200) as claimed in claim 18, wherein the at least one tooth involved in the rotation of the tens-place minute wheel (404) is to enter into one groove (404B) of the tens-place minute wheel (404) upon the tens-place minute wheel (404) reaching a second changeover position pertaining to the tens-place minute wheel (404), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place minute wheel (404), into the at least one corresponding groove (404B), the at least one tooth involved in the rotation of the unit-place hour wheel (406), is to engage with the at least one ratchet (406A) of the unit-place hour wheel (406).

22. The stamping system (200) as claimed in claim 18, wherein the at least one tooth involved in the rotation of the unit-place hour wheel (406) is to enter into one groove (406B) of the unit-place hour wheel (406) upon the unit-place hour wheel (406) reaching a third changeover position pertaining to the unit-place hour wheel (406), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place hour wheel (406), into the at least one corresponding groove (406B), the at least one tooth involved in the rotation of the tens-place hour wheel (408), is to engage with the at least one ratchet (408A) of the tens-place hour wheel (408).

23. The stamping system (200) as claimed in claim 18, wherein the set of time-printing wheels includes an AM/PM-wheel (410), and at least six grooves (408B) from the plurality of grooves (402B, 404B, 406B, 408B) are disposed on the side surface of the tens-place hour wheel (408).

24. The stamping system (200) as claimed in claim 23, wherein the at least one tooth involved in the rotation of the tens-place hour wheel (408) is to enter into one groove (408B) of the tens-place hour wheel (408) upon the tens-place hour wheel (408) reaching a fourth changeover position pertaining to the tens-place hour wheel (408), and

wherein in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place hour wheel (408), into the at least one corresponding groove (408B), the at least one tooth involved in the rotation of the AM/PM wheel (410), is to engage with the at least one ratchet (410A) of the AM/PM wheel (410).

25. The stamping system (200) as claimed in claim 18, wherein the set of characters includes at least one of numeric digits and alphabets. 26. The stamping system (200) as claimed in claim 18, wherein the periphery of each wheel of the plurality of wheels (1 14A, 1 14B, 212) is engraved with a set of twelve characters.

27. The stamping system (200) as claimed in claim 18, wherein the plurality of wheels (212) includes a set of date-printing wheels to print date information, the set of date-printing wheels including at least two year- wheels, at least one month-wheel, and two day-wheels.

28. The stamping system (200) as claimed in claim 18, wherein the periphery of each wheel of the plurality of wheels (212) is engraved with a set of at least ten characters. 29. The stamping system (200) as claimed in claim 18, wherein the set of magnetic field sensors is to communicate the determined magnetic orientation of the set of magnets, to the controller (204), and wherein the controller (204) is to detect a current set of characters, based on the determination result, wherein the current set of characters are the characters of the at least one wheel of the plurality of wheels (212) facing towards a to-be printed target.

30. The stamping system (200) as claimed in claim 29, wherein the controller (204) is to:

monitor the current set of characters of the plurality of wheels (21 2); obtain a current time information ;

match the monitored current set of characters with the current time information; and

output the matching result via the at least one indicator (210).

31. The stamping system (200) as claimed in claim 30, wherein the stamping system (200) comprises a real-time chip (RTC) coupled to the controller (204), and wherein the controller (204) obtains the current time information from the RTC. 32. The stamping system (200) as claimed in claim 31 , the stamping system

(200) includes a plurality of buttons, coupled to the controller (204), to allow a user to enter the current time information into the controller (204).

33. The stamping system (200) as claimed in claim 30, the stamping system (200) comprising:

a first display (214) to display the current set of characters of the plurality of wheels (212); and

a second display (216) to display the current time information.

34. The stamping system (200) as claimed in claim 18, wherein the controller (204) is communicatively coupled to the printing box (202) via a network (206).

35. The stamping system (200) as claimed in claim 18, wherein the set of magnetic field sensors are Hall Effect sensors.

36. The stamping system (200) as claimed in claim 18, wherein the at least one indicator (210) is light-emitting diode (LED). 37. A method of operation of a stamping system (200) as claimed in one of claims 18 to 36, the method comprising:

determining, by a set of magnetic field sensors, a magnetic orientation of a set of magnets disposed on each wheel of a plurality of wheels (21 2) of the printing box (202), wherein the plurality of wheels (21 2) includes a plurality of printing faces, wherein a set of printing faces from the plurality of printing faces are disposed on a periphery of each wheel of the plurality of wheels (21 2) and at least one printing face of the set of printing face includes a character; communicating the determined magnetic orientation to a controller (204);

determining, by the controller (204), an orientation of each wheel from a plurality of wheels (212) of the printing box (202), based on the determined magnetic orientation;

determining, by the controller (204), a current set of characters, based on the determined orientation of each wheel, wherein the current set of characters are the characters of the at least one wheel of the plurality of wheels (212) facing towards a to-be printed target;

determining, by the controller (204), whether the current set of characters of a plurality of wheels (212), match with a current time information obtained from a real-time chip (RTC);

upon determining a mis-match between the current set of characters and the current time information of the RTC:

in a manual mode, deactivating a power device and indicating, by the controller (204) and via at least one indicator (210), an operator for manual setting of the plurality of wheels (212) to match the current set of characters with the current time information, wherein the power device is one of an alternating current (AC) motor and a direct current (DC) motor; or in a non-manual mode, indexing a lever (208) of a stamp device (200A) of the stamping system (200) using the power device to match the current set of characters with the current time information; and

upon determining a match between the current set of characters and the current time information of the RTC, indicating, by the controller (204) and via the at least one indicator (210), a ready-to-use state of the stamping system (200) to the operator.

38. The method as claimed in claim 37, wherein the method comprises, upon determining the match between the current set of characters and the current time information of the RTC: resetting a face checking counter (FCC), provided in a memory coupled to the controller (204), wherein the FCC counts and stores a value of every minute-increment for which the match between the current set of characters and the current time information is not performed;

resetting a delay time counter (DTC), provided in the memory, wherein the DTC counts and stores a number of occurrence of a delay in rotation of the at least one wheel of the plurality of wheels (212);

loading the matched time information in a printing face tracking counter, wherein the printing face tracking counter is provided in the memory to store a value of the current set of characters; and

updating the printing face tracking counter for every indexing of the lever (208) to update the current set of characters.

39. The method as claimed in claim 38, wherein the method comprises, upon determining the match between the current set of characters and the current time information of the RTC:

determining whether the stamping system (200) is in an idle mode or an active mode;

upon determining that the stamping system (200) is in active mode: updating the values of the DTC and the FCC with every minute- increment of the RTC and deactivating the power device; and

comparing the value of the DTC with a predetermined tolerance value to determine whether the value of the DTC is greater than the predetermined tolerance value;

upon determining that the value of DTC is greater than the predetermined tolerance value, keeping the stamping system (200) in an ON state by an operator for updating a current time; and

upon determining that the value of DTC is one of less than or equal to the predetermined tolerance value, repeating the determination of whether the stamping system (200) is in idle mode or the active mode; and upon determining that the stamping is in idle mode:

determining whether the value of the DTC is one of less than or equal to zero;

upon determining that the value of the DTC is greater than zero:

performing at least one of incrementing the values of the DTC and the FCC for every minute increment of the RTC and decrementing the value of the DTC after every indexing of the lever (208) of the printing box (202) through the power device;

upon decrementing the value of the DTC, updating the printing face tracking counter and updating the first display (214) of the stamping system (200) with an updated current set of characters of the plurality of wheels (212); and

repeating the determination of whether the stamping system (200) is in the idle mode or the active mode; and upon determining that the value of the DTC is one of less than and equal to zero, comparing the value of the FCC with a set time interval;

upon determining that the value of the FCC is greater than the set time interval:

determining whether a timer of the RTC is to be updated;

upon determining that the timer of the RTC is to be updated, receiving user input for updating the timer via a keyboard of the stamping system (200) and repeating the determination of whether the current set of characters match with the current time information; and

upon determining that the timer of the RTC is not to be updated, repeating the determination of whether the current set of characters match with the current time information as claim in claim 38;

upon determining that the value of the FCC is one of less than and equal to the set time interval, incrementing the value of the FCC and the DTC for every minute increment of the RTC; and

repeating the indicating of the ready-to-use state of the stamping system (200) to the operator as claimed in claim 38. 40. The method as claimed in claim 37, wherein the method comprises: displaying the current set of characters on a first display (214); and displaying the current time information on a second display (216).

41. The method as claimed in claim 38, where the value of the FCC is updated for increment of every minute of the RTC, and the value of the DTC is updated for storing a number of pending rotations of the at least one wheel of the plurality of wheels (212).

Description:
STAMP DEVICE FOR PRINTING TIME

FIELD OF INVENTION

[0001 ] The present subject matter relates, in general, to stamp devices, and, particularly, to a stamp device and a stamping system for printing date and time information on documents.

BACKGROUND

[0002] Stamp devices or stamping devices may sequentially stamp or imprint date and message information on documents. The documents may be collected at front office desks, post offices, courts, and the like. Stamping ensures that the collected documents are properly identified and authenticated, so that they can be stored and used whenever required for future purposes.

BRIEF DESCRIPTION OF DRAWINGS

[0003] The following detailed description references the drawings, wherein:

[0004] FIG. 1 A illustrates a stamp device, according to an example embodiment of the present subject matter;

[0005] FIG. 1 B illustrates a stamp device, according to an example embodiment of the present subject matter;

[0006] FIG. 2 illustrates a stamping system, according to an example embodiment of the present subject matter;

[0007] FIG. 3 illustrates a method of operation of the stamping system, according to an example embodiment of the present subject matter; and [0008] FIG. 4 (a) to (e) illustrate printing wheels of the stamp device of FIG. 1 A to 2.

DETAILED DESCRIPTION

[0009] In general, a stamp device may include a numbering box having a plurality of numbering wheels. Each of the plurality of numbering wheels has printing faces on which characters are present. The characters may include numeric digits from 0 to 9 or alphabets. The plurality of numbering wheels is actuated by a lever, which enables rotation of the numbering wheels.

[0010] The conventional stamp device may be applicable only for printing the date on documents. However, there may be scenarios in which documents may require both date and time to be printed. This would be required for documents in which time is of essence. In an example, documents relating to court summons should have both date and time. In another example, postmarks on letters should also have both date and time stamped on them, which indicate the time the letters were received at the post office. Users may rely on other electronic devices for printing the time on the documents. In an example, the electronic devices may be a printer. The electronic devices may be coupled with a computer, which communicates electronic data information to be printed, to the electronic device.

[001 1] However, such electronic devices for obtaining and printing time has certain drawbacks. The electronic device occupies working space and requires electrical connections for establishing connection with the computer. In an example, the electrical connection may be established using a universal serial bus (USB) cable. The electronic device is also not portable due to its size and weight, thereby making it difficult to carry from one location to another location.

[0012] Further, the design of the electronic devices is complex as there are multiple intra communications and activities required for running the electronic devices. Hence, a specially trained and expert maintenance team may be required in cases of erroneous functioning of the electronic device. Due to its complex design, fixing the electronic device may be time consuming and costly. Thus, usage of sophisticated and complex means for printing time may not be appropriate for such documents where time is of essence. [0013] The present disclosure describes approaches in which a stamp device is used that prints both the date and the time together on documents. The stamp device described herein is useful in scenarios where time is of essence, and where it is essential that both date and time should be mentioned on a document. The disclosed stamp device is portable, easy to maintain, and cost effective.

[0014] The stamp device described herein may include a printing box that has at least eleven wheels each having characters engraved on the periphery of each wheel. In an example, the characters may be digits from 0 to 9 or alphabets. The wheels of the printing box are configured to rotate in conjunction with each other according to a pre-defined sequence, which is used for printing both the time and date alongside each other. The stamp device of the present disclosure eliminates the usage of an electronic device for printing the time along with the date on documents. The stamp device is less costly and also occupies less working place since usage of additional electronic devices are eliminated.

[0015] The stamp device is small in size and weight, thereby making it portable, i.e., easy to move or carry from one location to another location. The stamp device may also be operated by using only one power device. In an example, the power device may be a 220-voltage alternating current (AC) motor or a 12-voltage direct current (DC) motor. Thus, the stamp device has less connections, thereby making it easier and faster to set up, when compared with the conventional stamp device.

[0016] Further, due to the less number of connections required for operating the stamp device, the stamp device of the present disclosure is less complex and easier to set up due to the reduction in the number of components. This also makes the stamp device easier to maintain, and requirements of an expert maintenance team may not be required.

[0017] The following detailed description refers to the accompanying drawings (drawn not to the scale). Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar parts. While several examples are described in the description, modifications, adaptations, and other implementations are within the scope of providing a stamp device that prints both date and time. Accordingly, the following detailed description does not limit the disclosed examples. Instead, the proper scope of the disclosed examples may be defined by the appended claims.

[0018] FIG. 1 A illustrates a stamp device 100A, according to an example embodiment of the present subject matter. The stamp device 100A is to print time information. As shown, the stamp device 100A includes a printing box 102A, a linkage (not shown), a lever 104A, and a power device (not shown). The printing box 102A includes a plurality of wheels 114A for printing time information. Each wheel of the plurality of wheels 114A may include a periphery on which a set of characters are engraved. The plurality of wheels 114A may include a set of time-printing wheels including a unit- place minute wheel, a tens-place minute wheel, a unit-place hour wheel, and a tens-place hour wheel, and an AM/PM wheel. In an example, the set of characters may include numeric digits from 0 to 9 or alphabets. Each character may be provided on a printing face of each wheel to be printed. In an example, each wheel has twelve printing faces. The linkage may include an actuating pawl 106A, a plurality of ratchets, and a plurality of grooves.

[0019] A set of ratchets, from amongst the plurality of ratchets may be disposed on a side surface of each wheel of the plurality of wheels 114A.

[0020] The actuating pawl 106A may include one or more teeth 108- 1 A to 108-5A. The actuating pawl 106A may include more than five teeth. The stamp device 100A further includes a casing 1 10A, and a crank housing 1 12A. Each component is explained in further detail below.

[0021] The unit-place minute wheel, the tens-place minute wheel, the unit-place hour wheel, and the tens-place hour wheel may print the time. The AM/PM wheel may print either AM or PM along with the time, where AM means before noon and PM means after noon. The unit-place minute wheel may be placed at the right-most position and the tens-place hour wheel may be placed at the left-most position. In an example, the unit-place minute wheel may be placed at the right-most position and the AM/PM wheel may be placed at the left-most position. In another example, the unit- place minute wheel may be placed at the left-most position and the AM/PM wheel may be placed at the right-most position.

[0022] The lever 104A may be connected to the linkage to actuate the actuating pawl 106A for enabling a rotation of at least one wheel of the plurality of wheels 114A. In an example, the lever 104A is located at a left- hand side of the printing box 102A. The lever 104A is to provide an actuation of the wheels 1 14A of the printing box 102A. A power device may be connected to the lever 104A to move the lever 104A. In an example, the power device is a stepper motor. The lever 104A may be indexed via the stepper motor, once it is commanded or given a signal for indexing. In an example, the power device may be a 220-voltage alternating current (AC) motor or a 12-voltage direct current (DC) motor. The power device may be communicatively coupled with the controller. The power device may be connected to a cam. The cam may be provided to actuate the indexing of the lever 104A. For example, when the controller transmits a signal to the DC motor to rotate, the cam which may be mounted on the power device, enables the stepper motor for indexing the lever 104A to rotate for one rotation of the unit-place minute wheel. The unit-place minute wheel rotates for each indexing of the lever 104A.

[0023] Upon actuation by the lever 104A, at least one tooth of the actuating pawl 106A may engage with at least one ratchet of the plurality of ratchets for enabling the rotation of a corresponding wheel of the plurality of wheels 1 14A. In addition, the at least one tooth may enter into at least one corresponding groove upon rotation of the corresponding wheel by a predefined degree.

[0024] In an embodiment, the printing box 102A further includes the casing 1 10A that houses the printing box 102A. The casing 1 10A may include a plurality of side walls. Further, a circular slot may be formed through first and second side walls of the plurality of side walls. For example, the first and the second side walls may be positioned at opposite faces of the casing. In an example, the casing 1 10A may be made from metal.

[0025] The crank housing 1 12A may be placed within the casing 1 10A. Further, the crank housing may include a shaft and a crank element. The circular slot may be formed axially through the crank housing 1 12A and the shaft may be axially disposed within the crank housing 1 12A. Further, the plurality of wheels 114A may be mounted on the shaft. In an example, the crank element may include the actuating pawl 106A.

[0026] In an example, the circular slot is disposed in the crank housing

1 12A and are in alignment with the side walls of the casing. A shaft may be disposed within the crank housing 1 12A extending from one side of the crank housing 1 12A to the other. The wheels 1 14A are mounted on the shaft, which enable them to rotate.

[0027] In an embodiment, the linkage may be coupled with the plurality of wheels 114A. At least one groove from the plurality of grooves may be disposed on the side surface of the unit-place minute wheel. In an example, at least two grooves from the plurality of grooves may be disposed on the side surface of the tens-place minute wheel. Further, at least two grooves from the plurality of grooves may be disposed on the side surface of the unit-place hour wheel. In an example, the groove may be a depression or a narrow cut.

[0028] In an example, the unit-place minute wheel may have one groove, the tens-place minute wheel may have two grooves, the unit-place hour wheel may have two grooves, and the tens-place hour wheel and the AM/PM wheel may not have any groove. The teeth of the actuating pawl 106A may engage with the ratchets of the wheels 1 14A upon actuation received from the lever 104A. The teeth of the actuating pawl 106A also prevents overshooting of the wheels 114A. [0029] In an example, the AM/PM wheel is not linked to the rest of the wheels, and the AM/PM wheel may be manually rotatable to change a corresponding printing face.

[0030] The stamp device 100A may further include a plurality of retaining pawls disposed on the printing box 102A in a spring-loaded manner. A retaining pawl of the plurality of retaining pawls may engage with a ratchet of the plurality of ratchets to limit an over rotation of a corresponding wheel of the plurality of wheels 1 14A. In an example, the teeth of the actuating pawl 106A and the retaining pawls may prevent a reverse movement/rotation or an over rotation of the wheels 1 14A and allow the wheels 1 14A to rotation in one direction only. The mechanism in which the teeth 108-1 A to 108-5A engage with the ratchets and enter into the grooves of the wheels 114A is described in further detail below. The grooves may be placed where one tooth of the actuating pawl 106A comes into contact with ratchet for rotating printing face. Henceforth printing face will be taken as reference for disposing of the grooves.

[0031] As per an example embodiment, the set of characters may be engraved on the periphery of each wheel of the plurality of wheels 1 14A in a pre-defined sequence. Further, a completion of the pre-defined sequence may define a changeover position of each wheel of the plurality of wheels 1 14A. The at least one tooth may enter into the at least one corresponding groove of the at least one wheel of the plurality of wheels 1 14A upon reaching the changeover position.

[0032] In an example embodiment, the at least one tooth involved in the rotation of the unit-place minute wheel may enter into the at least one corresponding groove of the unit-place minute wheel upon the unit-place minute wheel reaching a first changeover position pertaining to the unit- place minute wheel. Further, the at least one tooth involved in the rotation of the tens-place minute wheel, may engage with the at least one ratchet of the tens-place minute wheel, in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place minute wheel, into the at least one corresponding groove.

[0033] The at least one tooth involved in the rotation of the tens-place minute wheel may enter into one groove of the tens-place minute wheel upon the tens-place minute wheel reaching a second changeover position pertaining to the tens-place minute wheel. The at least one tooth involved in the rotation of the unit-place hour wheel, may engage with the at least one ratchet of the unit-place hour wheel, in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place minute wheel, into the at least one corresponding groove.

[0034] The at least one tooth involved in the rotation of the unit-place hour wheel may enter into one groove of the unit-place hour wheel upon the unit-place hour wheel reaching a third changeover position pertaining to the unit-place hour wheel. The at least one tooth involved in the rotation of the tens-place hour wheel, may engage with the at least one ratchet of the tens- place hour wheel, in conjunction to the entering of the at least one tooth, involved in the rotation of the unit-place hour wheel, into the at least one corresponding groove.

[0035] The at least one tooth involved in the rotation of the tens-place hour wheel may enter into one groove of the tens-place hour wheel upon the tens-place hour wheel reaching a fourth changeover position pertaining to the tens-place hour wheel. The at least one tooth involved in the rotation of the AM/PM wheel, may engage with the at least one ratchet of the AM/PM wheel, in conjunction to the entering of the at least one tooth, involved in the rotation of the tens-place hour wheel, into the at least one corresponding groove. In an example, the at least one groove of the at least one wheel of the plurality of wheels 1 14A is disposed at the changeover position of each wheel.

[0036] FIG. 1 B illustrates a stamp device 100B, according to an example embodiment of the present subject matter. The stamp device 100B is to print date and time information. Some of the functions of the time printing wheels of the stamp device 100B may be similar to the stamp device 100A of FIG. 1 A. The stamp device 100B includes a printing box 102B, a lever 104B, and an actuating pawl 106B. The actuating pawl 106B may further include one or more teeth 108-1 B to 108-5B. The actuating pawl 106B may include more than five teeth. The stamp device 100B may further includes a casing 1 1 OB, and a crank housing 1 12B. Each component is explained in further detail below.

[0037] The printing box 102B includes a plurality of wheels 1 14B for printing date and time information. The plurality of wheels 1 14B may include a set of time-printing wheels including a unit-place minute wheel, a tens- place minute wheel, a unit-place hour wheel, a tens-place hour wheel, and an AM/PM wheel. The plurality of wheels 1 14B may further include a set of date-printing wheels for printing date information. The set of date-printing wheels including at least two year-wheels, at least one month-wheel, and two day-wheels. Each wheel of the plurality of wheels 1 14B may include a periphery on which a set of characters are engraved.

[0038] In an example, the periphery of each wheel of the plurality of wheels 1 14B may be engraved with a set of ten characters.

[0039] In another example, the periphery of each wheel of the plurality of wheels 1 14B may be engraved with a set of twelve characters.

[0040] In yet another example, the periphery of each wheel of the plurality of wheels 1 14B may be engraved with a set of more than twelve characters.

[0041] In an example, the set of date-printing wheels may include a unit-place year wheel, a tens-place year wheel, a hundred-place year wheel, a thousand-place year wheel, a unit-place month wheel, a tens-place month wheel, a hundred-place month wheel, a unit-place date wheel and a tens- place date wheel.

[0042] The unit-place year wheel, the tens-place year wheel, the hundred-place year wheel, and the thousand-place year wheel prints the year. The month wheel prints the corresponding month. The unit-place date wheel and the tens-place date wheel print the respective day. In an example, the wheels 114B print the date and time in the sequence starting from day at a left side, then the month, then the year, then AM/PM, and then ending with the time at a right side. In an example, the wheels 1 14B may print the date and time in the following format: 01 JAN 2018 PM 01 :34, on each document to be stamped. In an example, the unit-place minute wheel may be placed at the right-most position and the tens-place date wheel may be placed at the left-most position. In another example, the unit-place minute wheel may be placed at the left-most position and the tens-place date wheel may be placed at the right-most position.

[0043] In an example, each wheel of the set of date-printing wheels is manually actuated by a user to set a desired date for printing. In another example, each wheel of the set of date-printing wheels is coupled with a servo motor (not shown). The servo motor may be communicatively coupled to the controller. The controller may be coupled with a real-time chip (RTC) (not shown) which, in turn, may transmit a current date information to the controller. Based on the received current date information from the RTC, the controller may control the respective servo motors in order to actuate a corresponding date-printing wheel. The actuation is to match the date- printing wheels with the current date.

[0044] FIG. 2 illustrates a stamping system 200, according to an example embodiment of the present subject matter. The stamping system 200 includes a stamp device 200A including a printing box 202, a controller 204, a network 206. The stamp device 200A may further include a lever 208, an indicator 210, a linkage, and a power device.

[0045] The printing box 202 may include a plurality of wheels 212 for printing time information. Further, a set of characters may be engraved on a periphery of each wheel of the plurality of wheels 212. The plurality of wheels 212 may include a set of time-printing wheels. The set of time- printing wheels may include a unit-place minute wheel, a tens-place minute wheel, a unit-place hour wheel, a tens-place hour wheel, and an AM/PM wheel.

[0046] The printing box 202 may further include a plurality of magnets, an actuating pawl 218, a plurality of ratchets (not shown), and a plurality of grooves (not shown). In an example, a set of magnets, from amongst the plurality of magnets, may be disposed between at least two characters engraved on each wheel of the plurality of wheels 212. The at least one indicator 210 may be disposed on the printing box 202. The linkage may be coupled with the plurality of wheels 212. The linkage may include a plurality of magnetic field sensors. For example, a set of magnetic field sensors, from amongst the plurality of magnetic field sensors, is disposed in a stationary position besides each wheel of the plurality of wheels 212 to determine a magnetic orientation of the set of magnets.

[0047] In an example, the actuating pawl 218 may include one or more teeth and a set of ratchets, from amongst the plurality of ratchets, is disposed on a side surface of each wheel of the plurality of wheels 212. Further, at least one groove from the plurality of grooves may be disposed on the side surface of the unit-place minute wheel, at least two grooves from the plurality of grooves may be disposed on the side surface of the tens- place minute wheel, at least two grooves from the plurality of grooves may be disposed on the side surface of the unit-place hour wheel, at least six grooves from the plurality of grooves may be disposed on the side surface of the tens-place hour wheel, and the AM/PM wheel may not have any groove.

[0048] The lever 208 may be connected to the linkage to actuate the actuating pawl 218 for enabling a rotation of at least one wheel of the plurality of wheels 212. The power device may be connected to the lever 208 to move the lever 208. At least one tooth of the actuating pawl 218 may engage with at least one ratchet of the plurality of ratchets for enabling the rotation of a corresponding wheel of the plurality of wheels 212, upon actuation by the lever 208. [0049] The at least one tooth is positioned to enter into at least one corresponding groove upon rotation of the corresponding wheel by a predetermined degree. The controller may be communicatively coupled to the printing box 202, and the controller is to transmit a control signal to the power device for moving the lever 208.

[0050] In another example the stamping system 200 includes the printing box 202, the controller 204 communicatively coupled to the printing box 202 via the network 206, at least three hall effect sensors (not shown) disposed on each wheel of the printing box 202, and an indicator 210 disposed on the printing box 202. For example, the indicator 210 may be a light-emitting diode (LED). Three hall effect sensors are aligned against each wheel and are housed inside the printing box. The mechanism of the printing box 202 may be similar to the printing box 102A, 102B, as described in FIGS. 1 A and 1 B hereinabove.

[0051 ] In an example, the plurality of wheels 212 may include a plurality of printing faces. A set of printing faces from the plurality of printing faces may be disposed on a periphery of each wheel of the plurality of wheels 212. At least one printing face of the set of printing face includes a character. The character may be engraved on a corresponding printing face.

[0052] In an embodiment, the controller 204 is configured to monitor a set of printing faces of the wheels 212 of the printing box 202 and compare the printing faces with real-time date and time information. This leads to reduction in errors while stamping the date and time in each document.

[0053] A current printing face may be detected using magnets. The current printing face may be a printing face which is facing towards a to-be printed target. In an example, a current set of characters may be detected using magnets. The current set of characters may be a set of characters engraved on respective wheels, which are facing towards the to-be printed target. At least one magnet is placed between at least four printing faces of each of the wheels 212 of the stamping system 200. Each magnet may be fixed in a gap between two adjacent printing faces of the stamping system 200. The magnets may have two poles, which are north pole (N) and south pole (S). Each of the magnets are placed with either its North pole (N) or its south pole (S) facing outwards, i.e., towards the printing face. Depending on which pole of the magnet is facing outwards, a magnetic orientation of one of the wheels 212 is illustrated in Table. 1 below:

Table. 1

As shown above, N represents north pole, S represents south pole, O represents absence of a magnet in the gap between the printing faces. The association of the magnetic orientation with the respective printing faces, as shown in Table. 1 , may be applicable to printing wheels, each having at least twelve printing faces. The magnetic orientation of the magnet may be detected using a plurality of magnetic field sensors (not shown in FIG. 2). For example, the magnetic field sensors may include Flail Effect sensors, which are placed along each wheel of the printing box 202 of the stamping system 200. The controller 204 may include a face detection card that detects a current printing face of each of the wheels 212. A set of characters associated with the current printing faces may also be referred hereinafter as a current set of characters. The face detection card may include the plurality of magnetic field sensors. The magnetic field sensors may detect the poles of the magnets placed along the wheel which may be utilized for identifying a magnetic orientation of the wheel. Once the wheel rotates one step, there is a change in the magnetic field detected by the hall effect sensors due to change in magnetic orientation of the wheel. After determining the poles of the magnets placed along the wheel, the Hall Effect sensors communicate the determined poles of the magnets to the controller 204. Based on the determined poles, the controller 204 may determine magnetic orientation of each of the wheels 212. Further, the controller 204 may then determine the corresponding printing faces. The printing faces of each of the wheels 212 may be displayed in a first display 214. In another example, the magnetic orientation of the printing faces of the tens-place minute wheel is illustrated in Table. 2 below:

Table. 2

[0054] The association of the magnetic orientation with respective printing faces of the tens-place minute wheel, as shown in Table. 2, may be applicable to printing wheels, each having at least twelve printing faces.

[0055] In an example, a first set of six characters is disposed on a first set of six printing faces of the tens-place minute wheel and a second set of six characters is disposed on a second set of six printing faces of the tens- place minute wheel. The first set of six characters are similar to the second set of six characters.

[0056] Further, the controller 204 may receive a current updated date and time, for example from a real-time chip (RTC), and display the current date and the time in a second display 216. The content displayed in the second display 216 is matched with the content displayed in the first display 214. If there is a match, the controller 204 sends a signal to glow a green color on the LED 210. If there is a mis-match, the controller sends a signal to glow a red color on the LED 210 for indicating the operator to keep the printing box in idle state/non-working state so that a printing face may be rotated to match with the updated time.

[0057] The AM/PM wheel may be provided with a set of magnets. One of the N, S, and O orientation may be associated with an AM face of the AM/PM wheel. Further, one of the N, S, and O orientation, different from orientation associated with the AM face, may be associated with a PM face of the AM/PM wheel.

[0058] The stamping system 200 further includes a plurality of buttons, coupled to the controller 204, to allow a user to enter the current time information into the controller 204. The buttons may be included in a keyboard. The keyboard may be locked inside the stamping system 200 and may be opened using a mechanical key. The keyboard may include a plurality of keys. In an example, the keyboard may include four keys, which are an up key, a down key, an enter key, and a mode key. In an example, the four keys may be multifunctional keys, which may be appointed for different functions according to different modes of a setting required for the stamping system 200.

[0059] In an example, the set of characters may be engraved on the periphery of each wheel of the plurality of wheels 212 in a pre-defined sequence. A completion of the pre-defined sequence may define a changeover position of each wheel of the plurality of wheels 212. For example, the at least one tooth enters into the at least one corresponding groove of the at least one wheel of the plurality of wheels 212 upon reaching the changeover position. The position of the grooves with respect to the ratchets determines a contact position of the actuating pawl 218 with the ratchet of the wheel for performing pre-determined changeover of the wheel by rotation.

[0060] The set of magnetic field sensors may determine a magnetic orientation of the set of magnets placed on the wheels 212 and may communicate the determined magnetic orientation of the set of magnets, to the controller 204. Further, the controller 204 may detect a current set of characters, based on the determination result. The current set of characters may be the characters of the at least one wheel of the plurality of wheels 212 facing towards a to-be printed target. The controller 204 is further provided to monitor a current set of characters of the plurality of wheels 212. After monitoring, the controller 204 may obtain current time information and match the monitored current set of characters with a current time information. In addition, the controller may output the matching result via the at least one indicator. The stamping system 200 may also include a real time chip (RTC) coupled to the controller 204. The controller 204 may obtain the current time information from the RTC. [0061] FIG. 3 illustrates a method 300 of operation of the stamping system 200, according to an example embodiment of the present subject matter. In an embodiment, the stamping system 200 may operate using manual and non-manual methods. Each step is explained in further detail below. At step 302, the stamping system 200 is switched on. At step 304, it is checked whether a timer of the real-time chip (RTC) is required to be updated. If yes, then at step 306, a user may manually set the time using a keyboard of the stamping system 200. At step 308, it is checked whether the time setting using the keyboard is completed. If yes, then at step 310, the timer of the RTC is updated. If no, then step 306 is repeated. If the timer of the RTC is not required to be updated at step 304, then at step 312, it is checked whether the printing faces of the wheels 212 of the printing box 202 of the stamping system 200 for printing the time, match with the time of the RTC. If the printing faces do not match with the time of the RTC, then at step 314, it is checked whether a manual mode is selected. If a manual mode in not selected, then at step 316, the lever, for example the lever 208 of the stamp device 200A is indexed using a DC motor. This indexing may enable rotation of the unit-place minute wheel of the printing box 202 of the stamping system 200. The unit-place minute wheel rotates for each indexing of the lever 208 then goes to step 312. If at step 314, a manual mode is selected then, at step 318, the DC motor is deactivated, thereby allowing an operator to manually set the wheels 212. At step 320, it is checked whether the time setting using the manual method is completed. If no, then step 318 is repeated. If yes, at step 320, then method goes back to step 312 after activation of DC motor.

[0062] If the printing faces of the wheels 212 for printing the time are matching with the time of the RTC at step 312, then at step 322, a face checking counter (FCC), a delay time counter (DTC) are each reset. The FCC and the DTC are both may be provided in a memory (not shown) coupled to the controller 204 of the stamping system 200. The FCC counts and stores the number of times in minutes incremented after checking printing time with current time the printing faces of the wheels 212 have changed. The DTC counts and stores the number of times/instances where a delay in rotation of the wheels 212 has occurred. A printing face tracking counter is provided to store the tracked current printing faces, a set of characters of which are also referred hereinafter as a current set of characters, in the memory coupled to the controller 204 of the stamping system 200. The printing face tracking counter may also be referred hereinafter as a face tracking counter for the sake of brevity.

[0063] In an example, when the printing face tracking counter may determine a buffer printing face of one of the wheels 212. The buffer printing face may be disposed on one of the wheels 212 in case a difference in the number of printing faces is present in a wheel 212 with respect to the rest of the wheels 212. Upon determination of the buffer printing face, the proximity sensor may communicate a signal to the controller, and the controller may generate control signals to enable additional rotations of the unit-place minute wheel to skip the buffer printing face from printing.

[0064] In another example, the system 200 includes at least one proximity sensor (not shown) arranged in proximity to the wheels 212. The proximity sensor is to determine buffer printing face of one of the wheels 212. Upon determination of the buffer printing face, the proximity sensor may communicate a signal to the controller, and the controller may generate control signals to enable additional rotations of the unit-place minute wheel to skip the buffer printing face from printing.

[0065] At step 324, the stamping system 200 is ready for printing at least one of the date and time information, which may be referred as a ready-to-use state of the stamping system 200. At step 326, it is checked whether the stamping system 200 is taken for stamping, which may be referred to as an active mode of the stamping system 200. If yes, then at step 328 the DTC and the FCC are both updated at progress of every minute of RTC and the DC motor is deactivated. The DTC may be updated for keeping a number of pending rotations of the wheels 212 and the FCC is updated for each minute increment pertaining to the time taken from the RTC. At step 330, the DTC is compared with a predetermined tolerance value, and it is checked whether the DTC is greater than the predetermined tolerance value. For example, the predetermined tolerance value is 2 minutes. In an example, the predetermined tolerance value may be a delay that occurred by an operator of the stamping system 200 in imprinting documents. If yes, then at step 332, the stamping system 200 is kept in an ON state by the operator for updating the current time, where an audio or visual indication is provided for keeping the stamping system 200 in the ON state. If no, then steps 326 - 330 are repeated.

[0066] The stamping system 200 may include a proximity sensor (not shown) which is to detect if a stamping device 200A is in proximity to a target surface. Upon detection, the proximity sensor sends a signal to the controller to determine whether the stamping system 200 is in idle mode or active mode. If the stamping system 200 is not taken for stamping, which may be referred as the idle mode of the stamping system 200, at step 326, then at step 334, it is checked whether the value of the DTC is less than or equal to zero. If the value of the DTC is greater than zero, then at step 336, the DTC and FCC are incremented for each minute increment of the RTC. Further, the DTC may be decremented after each indexing of the lever 208 of the printing box 202 through the DC motor. Further, corresponding to the decrementing of the DTC, the printing face tracking counter is updated for every indexing of the lever 208 to change at least one of the printing face and a first display is updated for current printing faces. In an example, the printing face tracking counter is updated for every indexing of the lever 208 to change the current set of characters.

[0067] If the value of the DTC is less than or equal to zero, then at step 338, the FCC is compared with a set time interval, and it is checked whether the FCC is greater than the set time interval. If the FCC is greater than the set time interval, then step 304 onwards are repeated. If the FCC is less than or equal to the set time interval, then at step 340, the values of the DTC and the FCC are incremented for each minute increment. Further, step 324 and subsequently step 326 onwards are repeated.

[0068] FIG. 4 illustrates printing wheels of the stamp device 100A, 100B, 200A of FIG. 1 A, 1 B, and 2. The stamp device includes a plurality of wheels. In an example, the plurality of wheels includes a set of time-printing wheels including a unit-place minute wheel 402, a tens-place minute wheel 404, a unit-place hour wheel 406, a tens-place hour wheel 408, and an AM/PM wheel 410.

[0069] FIG. 4(a) illustrates the unit-place minute wheel 402, according to an example of the present subject matter. In an example embodiment, upon receiving the actuation from the lever, the first tooth engages with a corresponding ratchet 402A of the unit-place minute wheel 402. This allows the unit-place minute wheel 402 to rotate. The unit-place minute wheel 402 rotates for every actuation of the lever. The first tooth may enter into a corresponding groove 402B of the unit-place minute wheel 402 for a first changeover, when the printing faces of unit-place minute wheel 402 follow a first pre-defined sequence. The first pre-defined sequence may be Ό12345678900’. The first changeover may be from a change in printing face ‘9’ in the tenth position of the first pre-defined sequence to a change in printing face Ό’ in the eleventh position of the first pre-defined sequence.

[0070] The groove 402B of the unit-place minute wheel 402 may be positioned between the‘9’ in the tenth position of the sequence and the Ό’ in the eleventh position of the sequence. The first tooth may enter into the groove 402B of the unit-place minute wheel 402 when the first changeover of the first pre-defined sequence occur and the second tooth may engage with the ratchet 404A (as shown in FIG. 4(b)) of the tens-place minute wheel 404 (as shown in FIG. 4(b)), which enables the tens-place minute wheel 404 to rotate. Simultaneously, the first tooth may rotate the unit-place minute wheel 402.

[0071 ] In an example, the second tooth may engage with the ratchet 404A of the tens-place minute wheel 404, when the first tooth of actuating pawl contacts or approaches to contact with the ratchet 402A for the first changeover of the printing face from‘9’ in the tenth position of the sequence to the Ό’ in the eleventh position of the sequence.

[0072] The unit-place minute wheel 402 may include two additional buffer printing faces which are included to create buffer characters to match a count of characters of the unit-place minute wheel 402 with a count of characters of the rest of the wheels. Additional rotation of the unit-place minute wheel 402 may be performed in order to skip the count of the additional buffer printing face. For example, the 1 st and 12 th characters of the unit-place minute wheel 402 may be assigned the buffer printing faces.

[0073] FIG. 4(b) illustrates the tens-place minute wheel 404, according to an example of the present subject matter. In order for the actuation of tens-place minute wheel 404 to occur, the second tooth enters into a groove 404B of the tens-place minute wheel 404 for a second changeover, when the printing faces of the tens-place minute wheel 404 follow a second pre defined sequence. The second pre-defined sequence may be Ό12345012345’. The second changeover may be from a change in the printing face from‘5’ to Ό’ of the second pre-defined sequence. The tens- place minute wheel 404 has two grooves 404B, which are a first groove and a second groove. The first groove is positioned between the‘5’ in the sixth position of the sequence and the Ό’ in the seventh position of the sequence. The second groove is positioned between the‘5’ in the twelfth position of the sequence and the Ό’ in the first position of the sequence. The second tooth enters into the groove 404B, either the first groove or the second groove, of the tens-place minute wheel 404 each time the second changeover occurs. Then, the third tooth according engages with the ratchet 406A (as shown in FIG. 4(c)) of the unit-place hour wheel 406 (as shown in FIG. 4(c)), which enables it to rotate. Simultaneously, the second tooth may rotate the tens-place minute wheel 404.

[0074] In an example, the third tooth may engage with the ratchet 406A of the unit-place hour wheel 406, when the second tooth of actuating pawl contacts or approaches to contact with the ratchet 404A for the second changeover of the printing face from‘5’ in one of the sixth position and twelfth positions of the sequence to the Ό’ in one of the first and seventh positions of the sequence.

[0075] FIG. 4(c) illustrates the unit-place hour wheel 406, according to an example of the present subject matter. In order to actuate the rotation of the unit-place hour wheel 406, the third tooth enters into the grooves 406B of the unit-place hour wheel 406 for a third changeover, when the printing faces of the unit-place hour wheel 406 follow a third pre-defined sequence. The third pre-defined sequence may be Ό1234567890T. The third changeover may be from a change in the printing face from‘9’ to Ό’ or 1 to 0, of the third pre-defined sequence. For, example, the unit-place hour wheel 406 has two grooves 406B, which are a first groove and a second groove. The first groove is positioned between the‘9’ in the tenth position of the sequence and the Ό’ in the eleventh position of the sequence. The second groove is positioned between the in the twelfth position of the sequence and the Ό’ in the first position of the sequence. The third tooth enters into the groove 406B, either the first groove or the second groove of the unit-place hour wheel 406 each time the third changeover occurs. Then, the fourth tooth accordingly engages with the ratchet 408A (as shown in FIG. 4(d)) of the tens-place hour wheel 408 (as shown in FIG. 4(d)), enabling it to rotate. Simultaneously, the third tooth may rotate the unit-place hour wheel 406.

[0076] In an example, the fourth tooth may engage with the ratchet 408A of the tens-place hour wheel 408, when the third tooth of actuating pawl contacts or approaches to contact with the ratchet 406A for the third changeover of the printing face from one of ‘9’ in the tenth position of the sequence to Ό’ in eleventh position and ’T in twelfth position of the sequence to Ό’ in the first position of the sequence.

[0077] FIG. 4(d) illustrates the tens-place hour wheel 408, according to an example of the present subject matter. In order to actuate the rotation of the tens-place hour wheel 408, the fourth tooth enters into the grooves 408B of the tens-place hour wheel 408 for a fourth changeover, when the printing faces of the tens-place hour wheel 408 follow a fourth pre-defined sequence. The fourth pre-defined sequence may be Ό1010101010T. The fourth changeover may be from a change in the printing face from T to Ό’ of the fourth pre-defined sequence. The tens-place hour wheel 408 has six grooves 408B, which are a first groove, a second groove, a third groove, a fourth groove, a fifth groove, and a sixth groove. The first groove is positioned between the in the second position of the sequence and the Ό’ in the third position of the sequence. The second groove is positioned between the‘1 in the fourth position of the sequence and the Ό’ in the fifth position of the sequence. The third groove is positioned‘T in the sixth position of the sequence and the Ό’ in the seventh position of the sequence. The fourth groove is positioned between the‘T in the eighth position of the sequence and the Ό’ in the ninth position of the sequence. The fifth groove is placed between the‘T in the tenth position of the sequence and the Ό’ in the eleventh position of the sequence. The sixth groove is placed between the‘T in the twelfth position of the sequence and the Ό’ in the first position of the sequence.

[0078] The fourth tooth enters into one of the grooves 408B of the tens- place hour wheel 408 each time the fourth changeover occurs and the fifth tooth may engage with the ratchet 410A of the AM/PM wheel 410. Simultaneously, the fourth tooth, upon entering into one of the grooves 408B of the tens-place hour wheel 408, may rotate the tens-place hour wheel 408.

[0079] FIG. 4(e) illustrates the AM/PM wheel 410, according to an example of the present subject matter. The rotation of the AM/PM wheel 410 is actuated simultaneous to the completion of the fourth changeover. Simultaneous to the fourth changeover, the fifth tooth may engage with the ratchet 410A of the AM/PM wheel 410, enabling the AM/PM wheel 410 to rotate. [0080] In an example, the fifth tooth may engage with the ratchet 410A of the AM/PM wheel 410, when the fourth tooth of actuating pawl contacts or approaches to contact with the ratchet 408A for the fourth changeover of the printing face from Ί’ in one of the second, fourth, sixth, eighth, tenth, and twelfth positions of the sequence to Ό’ in one of the first, third, fifth, seventh, ninth, and eleventh positions of the sequence.

[0081] Therefore, as explained in the example embodiment of FIGS. 4(a) to 4(e) simultaneous to a changeover related to a lower order wheel, an actuation of the rotation of an immediate higher order wheel may be performed in conjunction with the corresponding lower order wheel. In an example, the unit-place minute wheel 402 pertains to the lowest order, and the AM/PM wheel 410 pertains to the highest order.

[0082] Although implementations of present subject matter have been described in language specific to structural features and/or methods, it is to be noted that the present subject matter is not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed and explained in the context of a few implementations for the present subject matter.