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Title:
CONTACT SWITCH DEVICE USING MAGNETS
Document Type and Number:
WIPO Patent Application WO/2003/065397
Kind Code:
A1
Abstract:
Disclosed is a contact switch device including a first arc-shaped gear (13) connected to a Bourdon tube, a second arc-shaped gear (18) rotating in the same direction as a pinion gear (14) engaged with the gear (13) while rotating reversely in accordance with a reaction thereof generated against the rotation of the pinion gear (14) when it comes into contact with a stopper (16 or 17), a pivoting magnet (22) pivoting in accordance with rotation of an assistant pinion gear engaged with the gear (18), a moving magnet (23) supported by a plate spring (25), and adapted to switch off contacts against the resilience of the plate spring when it is aligned with the pivoting magnet, and fixed magnet (24) for maintianing contacts in a switched-on state when it is aligned with the pivoting magnet. The plate spring switches on the contacts when the pivoting magnet is misaligned from the moving magnet.

Inventors:
KIM GI JIN (KR)
Application Number:
PCT/KR2003/000209
Publication Date:
August 07, 2003
Filing Date:
January 29, 2003
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
KIM GI JIN (KR)
International Classes:
H01H3/24; H01H35/36; H01H36/00; H01H3/40; (IPC1-7): H01H36/00
Foreign References:
US4529961A1985-07-16
US4613851A1986-09-23
JPH03149740A1991-06-26
JPS56633A1981-01-07
Attorney, Agent or Firm:
Lee, Dal-ro (4F Joyang Bldg., 646-4, Yeoksam-don, Kangnam-gu Seoul 135-911, KR)
Download PDF:
Description:
CONTACT SWITCH DEVICE USING MAGNETS Technical Field The present invention relates to a contact switch device using magnets. In particular, the present invention relates to a contact switch device which uses magnets adapted to maintain the ON/OFF state of the switch device in the operation/stopping of a pressurizing pump, thereby preventing the switch device from being repeatedly switched on/off, while maintaining a desired operation state of the pressurizing pump, thereby preventing the pressurizing pump and a motor adapted to drive the pressurizing pump from being damaged, and allowing the pressurizing pump to generate a uniform water pressure.

Background Art Conventional pressure switches use a Bourdon tube configured to expand or shrink in accordance with a variation in the pressure in a discharge conduit during the operation of a pressurizing pump, thereby switching on or off an electric circuit adapted to switch on or off the supply of electric power to the pressurizing pump.

Such a pressure switch includes a movable contact bar arranged between a lower contact and an upper contact. When the pressure in the Bourdon tube decreases, the movable contact bar pivots toward the lower contact, thereby causing the pressure switch to be switched on. Accordingly, the pressurizing pump operates.

On the other hand, when the pressure in the Bourdon tube increases, the movable contact bar pivots toward the upper contact, thereby causing the pressure switch to be switched off. Accordingly, the pressurizing pump is stopped.

The pressure switch is switched on or off in accordance with an ON or OFF state of contacts thereof, thereby operating or stopping the pressurizing pump. The contacts repeat switching of ON and OFF states in accordance with a momentary pressure variation caused by the switching of the pressurizing pump between operating and stopping states. As a result, the contacts and pressuring pump may be damaged. In order to avoid this problem, a self-maintaining circuit is conventionally equipped in an electrical

activating circuit. The self-maintaining circuit serves to maintain the ON/OFF state of contacts for a certain time.

In the above mentioned conventional pressure switch, the contacts are repeatedly switched on and off in accordance with a variation in the pressure of the Bourdon tube, so that the pressurizing pump is frequently switched between its operating and stopping states. As a result, impact may be applied to the pressuring pump and drive motor, so that they may be damaged. Although this problem may be eliminated by the provision of the self-maintaining circuit, the manufacturing cost of the pressure switch increases. Furthermore, there is a drawback in that it is difficult to maintain the pressure generated by the pressurizing pump at a desired level.

For this reason, it has been required to provide a contact switch which is capable of maintaining the operating or stopping state of the pressurizing pump for a certain time to reduce impact caused by the switching of the pressurizing pump between its operating and stopping states, thereby protecting the pressurizing pump and drive motor against the impact, while preventing repeated switching thereof between ON and OFF states to eliminate loss of electric power caused by repeated switching of the pressurizing pump between its operating and stopping states, and eliminating the provision of a self-maintaining circuit to reduce the manufacturing cost.

Disclosure of the Invention The present invention has been made in view of the above mentioned problems, and an object of the invention is to provide a contact switch device which uses magnets, thereby being capable of maintaining the ON/OFF state of contacts for a certain time, and thus, maintaining the operating or stopping state of a pressurizing pump to reduce impact applied to the pressurizing pump and a drive motor, while maintaining the current ON or OFF state of contacts until a predetermined pressure is obtained, without being switched to an OFF or ON state thereof.

Another object of the invention is to provide a contact switch device using magnets which is capable of reducing the number of contacting times of contacts to increase the life of those contacts, so that it can be semi- permanently used, while being capable of maintaining the ON/OFF state of the contacts in a mechanical fashion without using any additional means such

as a self-maintaining circuit, so that it is inexpensive, and has improvements in the operation reliability and efficiency of an associated pressurizing pump.

In accordance with the present invention, these objects are accomplished by providing a contact switch device comprising: a first arc- shaped gear connected to a Bourdon tube, and adapted to rotate within a predetermined angle; a pinion gear engaged with the first arc-shaped gear, and adapted to rotate in accordance with the rotation of the first arc-shaped gear; a second arc-shaped gear coupled to a rotating shaft of the pinion gear, and adapted to rotate in the same direction as the pinion gear while rotating reversely in accordance with a reaction thereof generated against the rotation of the pinion gear when it comes into contact with one of stoppers spaced apart from each other by a predetermined distance; an assistant pinion gear engaged with the second arc-shaped gear, and adapted to rotate in accordance with the rotation of the second arc-shaped gear; a pivoting magnet mounted to a rotating shaft of the assistant pinion gear, and adapted to pivot in accordance with the rotation of the assistant pinion gear; a moving magnet having the same polarity arrangement as the pivoting magnet, the moving magnet serving to switch off contacts when it is aligned with the pivoting magnet; a fixed magnet arranged at a position horizontally spaced apart from the moving magnet by a predetermined distance, the fixed magnet having the same polarity arrangement as the pivoting magnet while serving to maintain the contacts in a switched-on state; and a plate spring connected to one of the contacts, and adapted to be spaced apart from the other contact when the pivoting magnet is aligned with the moving magnet, thereby switching off the contacts to switch off the supply of electric power, while coming into contact with the other contact when the pivoting magnet is misaligned from the moving magnet, thereby switching on the contacts to switch on the supply of electric power.

Brief Description of the Drawings The above objects, and other features and advantages of the present invention will become more apparent after a reading of the following detailed description when taken in conjunction with the drawings, in which: Fig. 1 is a sectional view showing a contact switch device of the present invention in an ON state thereof;

Fig. 2 is a sectional view showing the contact switch of the present invention in an OFF state thereof; and Fig. 3 is a sectional view showing a moved state of a pivoting lever included in the contact switch of the present invention.

Best Mode for Carrying Out the Invention Now, the present invention will be described in detail with reference to the annexed drawings.

Fig. 1 is a sectional view showing a contact switch device of the present invention in an ON state thereof. Fig. 2 is a sectional view showing the contact switch of the present invention in an OFF state thereof. Fig. 3 is a sectional view showing a moved state of a pivoting lever included in the contact switch of the present invention.

As shown in Figs. 1 and 2, the contact switch device includes a Bourdon tube 11 adapted to perform an expansion or shrinkage in accordance with the pressure of pressurized water received from a pressurizing pump 10.

The contact switch device also includes a first arc-shaped gear 13 connected to the Bourdon tube 11 by a rod 12, and adapted to rotate about a rotating shaft 13a fixed at a certain position, a pinion gear 14 engaged with the first arc-shaped gear 13, and adapted to rotate about a rotating shaft 14a, and a second arc-shaped gear 18 frictionally coupled to the rotating shaft 14a of the pinion gear 14, and provided at one end thereof with an arc-shaped gear portion, and at the other end thereof with a pivoting lever 15 adapted to pivot between a pair of spaced stoppers 16 and 17. The second arc-shaped gear 18 is adapted to rotate in the same direction as the pinion gear 14 while rotating reversely in accordance with a reaction thereof generated against the rotation of the pinion gear 14 when the pivoting lever 15 comes into contact with one of the stoppers 16 and 17. The contact switch device further includes an assistant pinion gear 19 engaged with the second arc-shaped gear 18, a pivoting magnet 22 mounted on an upper surface of the assistant pinion gear 19, and adapted to pivot in accordance with rotation of the assistant pinion gear 19 between a left-rotation stopper 20 and a right-rotation stopper 21 arranged at opposite sides of the assistant pinion gear 19, a moving magnet 23 adapted to switch off the supply of electric power when it is aligned with the pivoting magnet 22, a fixed magnet 24 adapted to switch on the supply of

electric power when it is aligned with the pivoting magnet 22, and a plate spring 25 adapted to switch on/off the supply of electric power in accordance with the position of the moving magnet 23.

The Bourdon tube 11 expands or shrinks in accordance with the pressure of the pressurized water received from the pressurizing pump 10.

That is, the Bourdon tube 11 expands when the pressure of the pressurized water is high, while shrinking when the pressure of the pressurized water is low. A check valve 26 is installed between the Bourdon tube 11 and the pressurizing pump 10 in order to prevent the pressurized water introduced into the Bourdon tube 11 from flowing backwardly, thereby preventing the pressurizing pump 10 form being damaged.

The Bourdon tube 11 is formed at one end thereof with a connecting hole 12a adapted to connect the Bourdon tube 11 to the first arc-shaped gear 13 via the rod 12. A valve 27 is connected to a desired portion of the Bourdon tube 11 in order to discharge the water from the pressurizing pump 10 introduced in the Bourdon tube 11 therethrough.

The rod 12 is connected at one end thereof with the Bourdon tube 11, so that it is vertically moved in accordance with the expansion and shrinkage of the Bourdon tube 11. The rod 12 is connected at the other end thereof with the first arc-shaped gear 13. The first arc-shaped gear 13 is rotatable about the rotating shaft 13a rotatably mounted at a certain position. An arc- shaped gear portion is formed at one end of the first arc-shaped gear 13.

The pinion gear 14 is engaged with the first arc-shaped gear 13 so that it is rotated in accordance with rotation of the first arc-shaped gear 13.

The pinion gear 14 is centrally provided with the rotating shaft 14a.

The second arc-shaped gear 18 is fixedly mounted to the rotating shaft 14a of the pinion gear 14 so that it rotates along with the pinion gear 14.

The pivoting lever 15 is formed integrally with the second arc-shaped gear 18 so that it pivots about the rotating shaft 14a of the pinion gear 14.

A pair of spaced stoppers, that is, ON and OFF stoppers 16 and 17, are arranged at opposite sides of the pivoting lever 15, respectively. The stoppers 16 and 17 are coupled to selected ones of fixing holes formed at the support plate 28 or a cover (not shown) so that the space defined between the stoppers 16 and 17 is adjustable in accordance the pressure set by the user.

The second arc-shaped gear 18 is frictionally coupled to an upper

portion of the rotating shaft 14a of the pinion gear 14 in such a fashion that it rotates in the same direction as the pinion gear 14 while rotating reversely in accordance with a reaction thereof generated against the rotation of the pinion gear 14 when the pivoting lever 15 comes into contact with the ON or OFF stopper 16 or 17.

The assistant pinion gear 19 is engaged with the second arc-shaped gear 18. The pivoting magnet 22 is arranged on an upper surface of the assistant pinion gear 19 so that it is pivoted in accordance with rotation of the assistant pinion gear 19. The pivoting magnet 22 is held by a magnet holder 29 mounted to the assistant pinion gear 19. The left-rotation stopper 20 and right-rotation stopper 21 are arranged at opposite sides of the pivoting magnet 22, respectively, in order to limit the pivoting range of the pivoting magnet 22.

The magnet holder 29 serves to firmly hold the outer circumferential surface of the pivoting magnet 22 in order to prevent the pivoting magnet 22 from being separated from the assistant pinion gear 19.

The moving magnet 23 is arranged at a position spaced apart from the left-rotation stopper 20 in a direction opposite to the pivoting magnet 22 in such a fashion that it is aligned with the pivoting magnet 22 near the left- rotation stopper 20. The moving magnet 23 has the same polarity arrangement as the pivoting magnet 22. Accordingly, when the moving magnet 23 is aligned with the pivoting magnet 22, it is moved in a direction opposite to the pivoting magnet 22 in accordance with a repulsion effect generated between the pivoting magnet 22 and the moving magnet 23. As a result, the contacts are switched to an OFF state thereof. The fixed magnet 24 is arranged at a position spaced apart from the right-rotation stopper 21 in a direction opposite to the pivoting magnet 22 in such a fashion that it is aligned with the pivoting magnet 22 near the right-rotation stopper 20. The fixed magnet 24 has the same polarity arrangement as the pivoting magnet 22.

Accordingly, when the fixed magnet 24 is aligned with the pivoting magnet 22, it maintains the pivoting magnet 22 in a state of being in contact with the right-rotation stopper 20 in accordance with a repulsion effect generated between the pivoting magnet 22 and the fixed magnet 24. As a result, the contacts are maintained at an ON state thereof.

Similarly to the pivoting magnet 22, each of the moving magnet 23

and fixed magnet 24 is coupled to a magnet holder 29 so that it is firmly held.

A plate spring 25 is connected at one end thereof to a fixed contact 30. The moving magnet 23 is mounted to the other end of the plate spring 25. In accordance with this configuration, the contacts are switched to its OFF state when the pivoting magnet 22 is aligned with the moving magnet 23, while being maintained at its ON state when the pivoting magnet 22 is aligned with the fixed magnet 24.

Actually, each of the moving magnet 23 and fixed magnet 24 cannot be positioned at a position where it is accurately aligned with the pivoting magnet 22, by virtue of the repulsion effect generated between the facing magnets. Accordingly, the pivoting magnet 22 is maintained in a state of being misaligned from the moving magnet 23 or fixed magnet 24 by a certain angle, while coming into contact with the left-pivoting stopper 20 or right pivoting stopper 21. The misalignment angle is preferably 2 to 5°.

The fixed contact 30 is connected to a power supply source. When the plate spring 25 comes into contact with another fixed contact, the electric power from the power supply source is applied to the pressurizing pump 10, thereby causing the pressurizing pump 10 to operate. When the pivoting magnet 22 is aligned with the moving magnet 23, the moving magnet 23 is forced to move away from the pivoting magnet 22, thereby causing the supply of the electric power to be cut off. As a result, the operation of the pressurizing pump 10 is stopped.

When the valve 27 is opened in the stopped state of the pressurizing pump 10, the pressure in the Bourdon tube 11 is reduced, thereby causing the Bourdon tube 11 to shrink. As a result, the rod 12 connected to the Bourdon tube 11 is lowered, thereby causing the first arc-shaped gear 13 to rotate about the rotating shaft 13 a.

In accordance with the rotation of the rotating shaft 13a, the pinion gear 14 engaged with the first arc-shaped gear 13 rotates about the rotating shaft 14, thereby causing the pivoting lever 15 to pivot about the rotating shaft 14a. The pivoting of the pivoting lever 15 is carried out in the same direction as the pinion gear 14 until the pivoting lever 15 comes into contact with the ON stopper 16.

When the pivoting lever 15 comes into contact with the ON stopper 16, the pivoting lever 15 pivots reversely in accordance with a reaction

thereof against the rotation of the pinion gear 14. In accordance with the reverse pivoting of the pivoting lever 15, the second arc-shaped gear 18 rotates reversely, thereby causing the assistant pinion gear 19 to rotate.

The rotation of the assistant pinion gear 19 causes the pivoting magnet 22 coupled to the rotating shaft 19a to pivot. When the pivoting magnet 22 pivots toward the fixed magnet 24 beyond the position where the pivoting magnet 22 is aligned with the moving magnet 23, the moving magnet 23, which has been maintained at a separation position, returns to a contact position. Accordingly, the contacts are switched on in accordance with the resilience of the plate spring 25 connected to the fixed contact 30.

In accordance with the ON state of the contacts, electric power is applied to the pressurizing pump 10 which, in turn, operates to increase the water pressure in the Bourdon tube 11 to a predetermined level.

When the Bourdon tube 11 expands in accordance with the increased water pressure thereof, the rod 12 is gradually raised. As a result, the first arc-shaped gear 13 rotates about the rotating shaft 13a, and the pinion gear 14 rotates correspondingly. In accordance with the rotation of the pinion gear 14, the pivoting lever 15 pivots toward the OFF stopper 17, thereby causing the pivoting magnet 22 to pivot to the right-rotation stopper 21.

Subsequently, the pivoting magnet 22 is maintained in a state of being in contact with the right-rotation stopper 21.

When the pivoting lever 15 reaches the OFF stopper 17, the pivoting lever 15 pivots reversely in accordance with a reaction thereof against the rotation of the pinion gear 14. By virtue of the reverse pivoting of the pivoting lever 15 and the repulsion of the fixed magnet 24, the pivoting magnet 22 pivots reversely toward the moving magnet 23. When the pivoting magnet 22 is subsequently aligned with the moving magnet 23, it causes the moving magnet 23 to move from its contact position to its separation position. As a result, the supply of the electric power is cut off, thereby causing the pressurizing pump 10 to be stopped.

Industrial Applicability As apparent from the above description, the contact switch device having the above described configuration using magnets in accordance with the present invention has no failure because the switching-on/off operation of

contacts is carried out using a repulsion generated between the magnets. In particular, the ON/OFF state of the contacts is maintained until the pivoting lever reaches the ON stopper or OFF stopper. Accordingly, the contacts can be continuously maintained at the ON/OFF state thereof, so that it is possible to prevent the pressurizing pump from being damaged. When the pressure generated by the pressurizing pump is higher than a predetermined maximum pressure or lower than a predetermined minimum pressure, the pressurizing pump is operated. Thus, the pressurizing pump is stably operated.

Moreover, the life of the contacts can be extended. Accordingly, the contact switch device of the present invention can be semi-permanently used.

In addition, the contact switch device can be inexpensively manufactured.

Also, there are improvements in the operation reliability and efficiency of the pressurizing pump.

Although the preferred embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.