BACKGROUND OF THE INVENTION Pay telephones have evolved to have rather standard sizes, shapes, and configurations.

For example, in the United States, pay telephones have a standard shape and configuration in which there is a generally L-shaped lower housing to which is mounted an upper housing to form a very secure box. In such a standard pay telephone arrangement, the size and position of various components thereof are predetermined and fixed. For example, the coin acceptor/rejecter (discriminator), coin receptacle, face plate, etc. are fitted in standard positions within or on the pay telephone. An example of such a standard pay telephone arrangement is shown in U.S.

Patent 5,086,465 of Bass.

The standard pay telephone arrangements used in the United States have been designed and configured to accept certain U.S. coins, namely dimes, nickels, and quarters. Coins substantially smaller than a dime or substantially larger than a quarter are not suitable for use in U.S.-style standard pay telephones. Thus, U.S.-style pay telephones will accept coins as small as about 1 7.5mm (roughly the size of a U.S. dime) and as large as about 24.5mm (roughly the size of a U.S. quarter). This yields a rather narrow dynamic range for the pay telephone. In other countries, pay telephone have assumed different configurations, with the largest known coin capacity being about 30 or 31mm.

It would be desirable to accept coins larger than 25 or 30mm. Moreover, it would be desirable to develop a single "universal" pay telephone that could be used in the United States or overseas and accept coins as small as a dime or smaller and yet accept coins larger than the largest coins currently accepted in known pay telephones. Specifically, it would be desirable to provide a pay telephone which could accept coins as large as about 35mm or so (some current coinage is about 35mm, but is too large to be accepted in known pay telephone arrangements).

Heretofore the provision of a universal pay telephone arrangement which could accept coins as large as 35mm has proved elusive. This is so because one cannot simply take the existing coin path components (the coin input slot, the coin discriminator, the coin escrow unit, the coin return, etc.) and scale them up accordingly to handle larger coins. This is so because simply scaling everything up would ordinarily require making the pay telephone housing substantially larger, something which is unacceptable in the marketplace. For example, in the known prior art, it has been common to evaluate the size of the coin in a coin discriminator using an array of photosensors. For example, U.S. Patent 4,474,281 of Roberts. et al relates to an apparatus and method for coin diameter computation in which arrays of photo sensors are used to detect the diameter of a coin. The greater the dynamic range (the greater difference between the maximum dimension and the minimum dimension of an accepted coin), the greater the number of photosensors required. This typically requires longer and longer coin paths in order to allow the array of photosensors to be positioned along the coin path to effectively discriminate different size coins. Unfortunately, increasing the length of the coin path in the discriminator is not a practical solution because there is only so much room inside the standard pay telephone housing and there simply isn't enough room to lengthen the coin path in the discriminator sufficiently to allow the maximum diameter of a detected coin to be increased from 24.5mm to 35mm.

Thus, one can see that the coin discriminator cannot simply be "scaled up" in order to achieve a greater dynamic range. Rather, it is necessary to rethink and redesign the coin discriminator in order to achieve the desired increase in dynamic range, while still maintaining the overall dimensions of the discriminator in order to fit it within the confines of a standard pay telephone housing. Moreover, every part of the coin path from the input chute to the coin return must be similarly rethought in order to provide an increase in coin size capacity while still fitting within the interior of a standard pay telephone housing.

Accordingly, it can be seen that a need yet remains for a pay telephone which is generally sized and configured like a standard pay telephone and yet which has the capacity for handling large diameter coins, in particular coins as large as about 35mm. It is to the provision of such a pay telephone that the present invention is primarily directed.

SUMMARY OF THE INVENTION Briefly described, the present invention comprises a coin operated pay telephone which is specially adapted to have a large capacity coin path capable of accepting and processing coins as large as about 35 mm. in diameter. The pay telephone comprises a coin receptacle for collecting coins and having means for admitting therein coins as large as 35 mm. The pay telephone also includes a coin return device for returning coins and slugs as large as 35 mm. to a user of the pay telephone. The coin operated pay telephone also comprises a coin validator for evaluating coins as large as 35 mm. and for rejecting slugs and invalid coins and accepting valid coins. The coin operated pay telephone also includes a coin escrow device for receiving accepted coins from the coin validator in a hopper and having means for selectively discharging coins from the hopper to the coin receptacle and to the coin return device. The means for selectively discharging and the hopper are each sized and adapted for processing coins as large as 35 mm.

Preferably, the coin validator comprises an electronic coin validator including first photo sensor means for evaluating the diameter of the coin, second photo sensor means for evaluating the thickness of the coin, and magnetic coil means for evaluating the material composition of the coin.

Also preferably, the means for admitting coins into the coin receptacle comprises a coin opening sized to admit coins at least as large as 35 mm. and a movable door for uncovering and covering said coin opening as the coin receptacle is placed in the phone and removed therefrom.

Preferably, the coin escrow device comprises a large volume coin hopper and a pivotal door beneath the hopper. Pivotal support means are positioned beneath the pivotal door for supporting the door in an escrow position and selectively moving the door to a coin acceptance position and a coin return position.

The invention allows the use of coins as large as about 35 mm., which represents a substantial improvement over the known prior art. In this regard, each of the major components presented a formidable design challenge. It was not possible to simply take the existing individual components known in the art and to scale them up accordingly to make larger coin paths within each of them (while keeping the same operating principles) and still make a coin operated pay telephone that would work and fit within the standard enclosure. For example, if one were to take a typical prior art coin escrow mechanism and simply make it larger, it might

be physically possible to make the escrow's coin hopper big enough to hold a 35 mm. coin.

However, these larger coins tend to be heavier as well, with the result being that an enlarged prior art escrow probably would experience difficulty in discharging the larger, heavier coins (typical prior art escrows effect a small lifting of the coins prior to discharge). Thus, the novel coin operated pay telephone utilizes a unique escrow (among other unique components) in order to achieve the large capacity coin path, while providing a workable phone that fits within existing standard enclosures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES FIG. 1 is a right side, elevational view of a pay telephone in accordance with a preferred embodiment of the present invention.

FIG. 2 is a back, elevational view of the pay telephone of FIG. 1.

FIG. 3A is a block diagram representation of a control unit of the pay telephone of FIG. 1.

FIG. 3B is a block diagram representation of a control unit of a pay telephone in accordance with an alternate embodiment of the present invention.

FIG. 4A is a perspective illustration of a coin validation apparatus according to a preferred form of the invention.

FIG. 4B is a perspective view of the coin validation apparatus of FIG. 4A, shown with some small components removed for clarity.

FIG. 4C is a sectional view of a portion of the coin validation apparatus of FIG. 4A.

FIG. 5A is a perspective illustration of a portion of the coin validation apparatus of FIG. 4A.

FIG. 5B is a front elevation view of the coin validation apparatus portion of FIG. 5A.

FIG. 6 is a schematic illustration of a part of the apparatus of FIG. 4 and the operation thereof.

FIG. 7 is a schematic illustration of operation of a part of the apparatus of FIG. 4.

FIG. 8 is a perspective, partially exploded view of a coin escrow apparatus according to a preferred form of the invention.

FIG. 9 is a schematic, functional illustration of the coin escrow apparatus of FIG. 8.

FIG. 10 is a perspective illustration of a coin escrow apparatus according to another preferred form ofthe invention, shown with coin acceptance and coin rejection adapters mounted thereto.

FIG. 11 is a side view of the coin escrow apparatus of FIG. 10.

FIG. 12 is a front, left perspective view of the coin escrow apparatus of FIG. 10, shown with the coin acceptance and coin rejection adapters removed for clarity.

FIG. 13 is an exploded view of the coin escrow apparatus of FIG. 10.

FIG. 14 is an exploded view of a portion of the coin escrow apparatus of FIG. 10.

FIG. 15 is a perspective, right, rear view of the coin escrow apparatus of FIG. 10.

FIG. 15A is an elevation view of a portion of the coin escrow apparatus of FIG. 10.

FIG. 1 6A is a sectional view of a portion of the coin escrow apparatus of FIG. 10.

FIG. 16B is a plan view of a portion of the coin escrow apparatus of FIG. 10.

FIG. 17 is a right side, elevational, schematic view of a coin return device according to a first preferred embodiment of the invention.

FIG. 17A is a front, elevational view of the coin return device of FIG. 17.

FIG. 18 is a right side, elevational view of a tamper-resistant coin return device, according to a second preferred embodiment of the present invention, showing the tamper- resistant coin return device installed within a pay telephone.

FIG. 19 is an isolated, partially cut-away, right side, elevational view of the tamper- resistant coin return device of FIG. 18.

FIG. 20 is an isolated, partially cut-away, front, elevational view of the tamper-resistant coin return device of FIG. 18.

FIG. 21 is an enlarged view of a portion of FIG. 19, showing a folding door and a trap door of the coin return device of FIG. 19.

FIG. 22 is a partial, right side, schematic view of the coin return device and coin return chute of FIG. 17, showing the components of the coin return device in a first orientation.

FIG. 23 is a partial, right side, schematic view of the coin return device and coin return chute of FIG. 17, showing the components of the coin return device in a second orientation.

FIG. 24 is a partial, right side, schematic view of the coin return device and coin return chute of FIG. 17, showing the components of the coin return device in a variant of the second orientation.

FIG. 25 is a partial, right side, schematic view of the coin return device and coin return chute of FIG. 17, showing the components of the coin return device in a variant of the second orientation.

FIG. 26 is a front perspective view of a coin receptacle cover, according to a preferred embodiment of the present invention, attached to a coin receptacle box.

FIG. 27 is a top, plan view of the coin receptacle cover of FIG. 26.

FIG. 28 is a partial cut-away, top, plan view of the coin receptacle cover of FIG. 26, shown in an armed, ready-to-be-installed configuration.

FIG. 29 is a partial cut-away, top, plan view of the coin receptacle cover of FIG. 26, shown in a triggered, installed configuration.

FIG. 30 is a partial cut-away, top, plan view of the coin receptacle cover of FIG. 26, shown in a triggered and locked (removed) configuration.

FIG. 31 is a partial cut-away, top, plan view of the coin receptacle cover of FIG. 26, shown in an intermediate configuration.

FIG. 32 is a top, plan view of an actuator arm of the coin receptacle cover of FIG. 26.

FIG. 33 is a top, plan view of a movable door of the coin receptacle cover of FIG. 26.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing figures, FIGS. 1 and 2 display a pay telephone 1000 with a large capacity coin path according to a preferred embodiment of the invention. The pay telephone 1000 comprises a housing 1002 having a cavity 1004 therein. The pay telephone 1000 further comprises an input chute 1006, a coin validator device 1008, a coin escrow device 1010, a coin receptacle 1012, and a coin return device 1014 which are connected to the pay telephone's housing 1002 within its cavity 1004. The input chute 1006 is mounted near the top of cavity 1004 and receives coins from a user of the pay telephone 1000 through a slot defined in the front of the pay telephone's housing 1002. The input chute 1006 directs the received coin(s) in a generally downward and rearward direction into the coin validator device 1008 which is

positioned beneath the input chute 1006. Note that the input chute's coin receiving slot and internal passages are sufficiently large in dimension so as to enable the input chute 1006 to admit large coins having a diameter, or maximum dimension, at least as large as 35 mm.

The coin validator device 1008, upon receiving a coin from the input chute 1006, determines whether the coin should be accepted or rejected by the pay telephone 1000. The coin validator device 1008 makes this determination by analyzing and comparing, while the coin descends through the coin validator device 1008, the coin's material, maximum dimension, and thickness against known values of these same parameters for coins which have been previously determined to be acceptable to the pay telephone 1000. If the coin validator device 1008, upon such analysis, determines that the coin's material, maximum dimension, and thickness render the coin acceptable, the coin validator device 1008 directs the acceptable coin into chute 1020 which resides between and connects to the coin validator device 1008 and the coin escrow device 1010.

After descending through chute 1020, the acceptable coin enters the coin escrow device 1010 which is mounted beneath the chute 1020 and, hence, beneath the coin validator device 1008.

If, alternatively, the coin validator device 1008 determines that the coin is not acceptable, the coin validator device 1008 directs the coin into reject chute 1022 which descends, within cavity 1004 of the pay telephone's housing 1002, between the coin validator device 1008 and a coin return chute 1024, described below. The coin path within the coin validation device 1008 is large enough to accept large coins having a maximum dimension of at least as great as 35mm. As the user of the pay telephone 1000 may insert multiple coins into the input chute 1006, the coin validator device 1008 similarly handles each such coin.

The coin escrow device 1010 temporarily stores acceptable coins until, as further described below, either (1) the user's telephone call is successfully completed and the acceptable coins are directed toward the coin receptacle 1012 for storage until collected by a representative of the pay telephone's owner, or (2) the user's telephone call is not successfully completed and the user hangs up to cause the coin escrow device 1010 to release and direct the acceptable coins into the coin return chute 1024. The coin escrow device 1010, chutes 1020, 1022, 1024, and the coin return device 1014 each provide a coin path large enough to accept large coins having a maximum dimension of at least as great as 35mm. The coin return chute 1024, mounted within the pay telephone's cavity 1004, couples to the coin escrow device 1010 and to the reject chute

1022. The coin return chute 1024 descends in a generally downward direction and connects to the coin return device 1014. The coin return device 1014 mounts to the pay telephone's housing 1002 near the bottom of cavity 1004 and enables the return of coins to the pay telephone's user via an indirect path which substantially prevents stuffing by thieves attempting to steal money from the pay telephone 1000. A coin acceptance chute 1026 connects to the coin escrow device 1010 and extends to a location above the coin receptacle 1012. The coin receptacle 1012 comprises a cover 1030 which mounts atop a collection box 1032. Coins released by the coin escrow device 1010 fall through the coin acceptance chute 1026 and into the coin receptacle 1012 through an opening of the cover 1030.

Referring now to Figs. 3A and 3B, the pay telephone 1000, according to the preferred embodiment, further comprises a controller (also referred to as a "chassis") 1040 which connects to a coin validator interface 1042 via bi-directional signal path 1044. The coin validator interface 1042 connects to the coin validator device 1008 through bi-directional signal path 1046. The controller 1040 also connects to a coin escrow interface 1050 through bi-directional signal path 1052. The coin escrow interface 1050 connects to the coin escrow device 1010 through bi- directional signal path 1054. A telephone line interface 1056 connects to the controller 1040 via bi-directional signal path 1058 and connects to equipment at a telephone company central office via bi-directional signal path 1060.

In operation, the coin validator interface 1042 receives signals from the coin validator device 1008, via signal path 1046, which indicates the denominations of coin(s) which are rendered acceptable by the coin validator device 1008, and which are directed, by the coin validator device 1008, to the coin escrow device 1010 through chute 1020. The coin validator interface 1042 communicates this denomination information to the controller 1040 through signal path 1044. The controller 1040 communicates information representative of the denominations to the telephone line interface 1056 via signal path 1058. The telephone line interface 1056 communicates the representative information to the equipment at telephone company's central office through signal path 1060. Upon determining that the user of the pay telephone 1000 has deposited an appropriate amount of money in the pay telephone 1000, the equipment at the telephone company's central office establishes a communication link between the pay telephone 1000 and the telephone company's central office in order to receive a telephone number

associated with a destination telephone of a party with whom the user of the pay telephone 1000 wishes to communicate. Equipment at the telephone company's central office then processes the telephone number and attempts to establish a communication session between the pay telephone 1000 and the destination telephone. If a successful communication session is established between the pay telephone 1000 and the destination telephone, the equipment at the central office enables the pay telephone's user to converse with the party. Upon termination of the communication session, the equipment at the central office signals the pay telephone's controller 1040, via the telephone line interface 1056 and signal path 1058, 1060, to accept for deposit the acceptable coin(s) input to the pay telephone 1000 by the user. After receiving such a signal, the controller 1040 communicates an instructive signal to the coin escrow device 1010, through the coin escrow interface 1050 and signal paths 1052, 1054, to instruct the coin escrow device 1010 to direct the temporarily stored, acceptable coin(s) to the coin receptacle 1012 via coin acceptance chute 1026. If, on the other hand, a communication session between the pay telephone 1000 and the destination telephone is not successfully established, the equipment at the telephone company's central office communicates a signal to the pay telephone's controller 1040, via the telephone line interface 1056 and signal paths 1058, 1060, which instructs the pay telephone 1000 to return the coin(s) to the user. The controller 1040 then communicates an instructive signal to the coin escrow device 1010, via the coin escrow interface 1050 and signal paths 1052, 1054, which instructs the coin escrow device 1010 to direct the temporarily stored, acceptable coin(s) to the coin return device 1014 through the coin return chute 1024. Note that coin(s) which were determined to be unacceptable by the coin validator device 1008, as described above, also travel through the coin return chute 1024 and into the coin return device 1014.

In an alternate embodiment of the present invention shown in FIG. 3B, the pay telephone 1000 further comprises a controller 1040 which connects to a coin validator interface 1042 via bi-directional signal path 1044. The coin validator interface 1042 connects to the coin validator device 1008 of the pay telephone 1000 through bi-directional signal path 1046. A coin escrow interface 1050 connects to the controller 1040 through bi-directional signal path 1052 and connects to the coin escrow device 1010' through bi-directional signal path 1054. Operation of the controller 1040, the coin validator interface 1042, and the coin escrow interface 1050 is substantially similar to the operation of their respective counterparts of the preferred embodiment

with the exception that the controller 1040 is an intelligent, or smart, controller and does not communicate with equipment at the telephone company's central office. Instead, the controller 1040, itself, determines whether the user has deposited sufficient funds into the pay telephone 1000 to allow placement of a telephone call. The controller 1040 also determines, on its own, whether to instruct the coin escrow device 1010 to accept temporarily stored coin(s) for deposit in the coin receptacle 1012 or to return the temporarily stored coin(s) to the user through the coin return device 1014.

Note that the coin validator device 1008, the coin escrow device 1010, the coin receptacle 1012 (including cover 1032), and the coin return device 1014 include novel features which enable them to handle and process multiple large, coins having a diameter, or maximum dimension, measuring at least as large as 35 mm. Furthermore, these components and the passages through chutes 1006, 1020, 1022, 1024, 1026 define a large capacity coin path therethrough which is capable of handling many such large coins.

The following subsections more fully describe the coin validator device 1008, the coin escrow device 1010, the coin receptacle 1012, and the coin return device 1014 with reference to appropriate figures.

COIN VALIDATION DEVICE FIGS. 4A-4C show a coin validation apparatus 1008 for use in a pay telephone according to a preferred form of the invention. In FIG. 4B, some of the small components have been removed in order to show other details that otherwise would be hidden from view. The coin validation apparatus 1008 consists of two large chassis pieces hinged to one another. The apparatus includes a large chassis piece 11 and a second large chassis piece 12 which is hinged to the first chassis piece 11 by hinges indicated generally at 13 and 14. The hinges allow the second chassis piece 12 to pivot about hinge axis 16 in order to provide access to the interior of the coin validation apparatus. The hinges 13 and 14 include upper and lower hinge halves 17 and 18 and 19 and 21. The hinges also include hinge pins, such as hinge pin 22, which act as the axles.

Chassis piece 12 is molded from high-impact plastic and consists essentially of three flat sections including lower vertical section 26, upper vertical section 27, and an inclined section 28 extending from the lower section 26 to the upper section 27.

Together, the chassis pieces 11 and 12 define an entry slot generally indicated at 31 for admitting coins into the coin validation apparatus 1008. The chassis piece 12 also includes bosses 32 and 33 for receiving an entry sensor 34 and an exit sensor 35. Furthermore, as will be seen in subsequent figures, the first chassis piece 11 has correspondingly placed bosses. The entry sensor comprises an LED emitter and a photo detector. Likewise, the exit sensor comprises an LED emitter and a photo detector.

The second chassis piece 12 is molded to receive a diameter sensor in the area generally indicated by reference numeral 30. As shown in FIG. 4A, the diameter sensor 40 includes a half- cylindrical reflector 46. As shown in FIGS. 4B and 4C, included therein are sockets 36 and 37 for receiving infrared LED emitters. An opening 38 extends from the outside surface of the chassis piece 12 all the way through the chassis piece 12 to the inside. The reader will note that as shown in FIGS. 4B-4C, the sockets shield the LEDs from directing their output through the aperture 38 directly. Rather, the light directed through the aperture 38 is indirect and diffuse.

Indeed, there is a narrow, light-blocking isthmus 39, 41 between the sockets 36, 37 and the aperture 38. The chassis piece 12 also includes four mounting holes, such as mounting hole 42 for securing the reflector element 46 over the LEDs and the aperture.

A recessed socket 43 and an upstanding post 44 are provided in the chassis piece 12 for receiving a magnetic coil 47 (a second magnetic coil, unshown, is placed parallel to and spaced apart from coil 47).

Referring now to FIGS. 5A and 5B, chassis piece 11 can be considered in greater detail. Chassis piece 11 defines a coin path generally beginning at the entry slot 31 and extending straight downwardly to a first inclined coin ramp 51. First coin ramp 51 is oriented at a 20 degree angle with respect to horizontal so that after a coin is received through the coin slot 31 and impinges on first coin ramp 51 at location 51a, it rolls downwardly (to the right in FIGS. 5A and 5B) to the end 5 le of the first coin ramp. With the chassis piece being made of high impact plastic, the first coin ramp 51 preferably comprises a metal insert to better absorb the shock and wear of metal coins impinging thereon and rolling thereby.

Water shed tracks generally indicated at 52 are positioned adjacent the end 51e of the first coin ramp 51 for peeling excess moisture off of the coins and transporting it away. Such water shed tracks are well-known in the industry.

The water shed tracks are adjacent a second coin ramp 53. Like first coin ramp 51, second coin ramp 53 includes a metal insert or wear plate for durability. Also as in first coin ramp 51, second coin ramp 53 is angled at 20 degrees relative to the horizontal, although in this instance the orientation is reversed such that the coins falling off the end of the ramp 51e and across the water shed tracks 52 now impinge the second coin ramp in the vicinity of 53a and descend downwardly (to the left in FIGS. 5A and 5B). Adjacent the distal end 53e of the second coin ramp 52 is positioned a short ramp extension 54, which is aligned with and co- extensive with second coin ramp 53. As will be described more fully below, the ramp extension 54 serves as part of a thickness sensor. In this regard, the ramp extension 54 includes an opening or aperture 54a. After traversing ramp extension 54, the coin falls downwardly in the direction of direction arrow 56 toward third ramp 57. Like the other two ramps, third ramp 57 includes a metal insert for durability. Ramp 57 also is inclined at a 20 degree angle relative to horizontal and is parallel to first ramp 51. At the distal end 57e of third ramp 57, the coin path continues downwardly in the direction of direction arrow 58 (for the coin return path).

Referring now again to the top of the aforedescribed coin path, a detector 64 is positioned in the entry path and is directly opposite the LED emitter 34. Together, the LED emitter 34 and the detector 64 comprise an entry sensor to indicate when a coin has crossed through the entry slot 31 and has begun down the coin ramp 51. Likewise, a detector 65 is positioned near the exit and opposite the LED emitter 35 of the chassis piece 12. Together, the LED 35 and sensor 65 make up an exit sensor to indicate that a coin has been passed to the coin box (unshown in the figures).

Intermediate the ends of the second ramp 53, an opening or aperture 61 is formed in the chassis piece 11 adjacent the coin path. The aperture 61 lies adjacent a large area detector 62 and shrouds all but a narrow strip thereof. Together with the LEDs and the half-cylindrical reflector positioned in the chassis piece 12, the aperture 61 and the wide area detector 62 make up a diameter sensor positioned along the coin path. Like the coin path, the diameter sensor

is adapted to accept coins up to 35 millimeters in diameter. That is to say, measured lengthwise, the wide area detector exceeds 35 millimeters in length.

Downstream of the diameter detector, a thickness sensor is positioned along the coin path and generally comprises a hooded light source generally indicated at 67 and a wide area detector positioned beneath ramp extension 54. In this way, light shining from the hooded light source 67 across the coin path impinges upon the ramp extension 54 and only a small sliver of it extends through the aperture 54a and impinges upon the detector element positioned beneath the ramp extension 54. If desired, a grating or gridlines can be provided between the light source 67 and the detector beneath the ramp extension 54, with the gridlines or grating running parallel to the second ramp 53. With the grating or gridlines extending parallel to the ramp, they extend perpendicularly to the path of light from the light source to the wide area detector. This has the effect of minimizing "skimming" or reflecting light that otherwise would be reflected off the surface of the chassis piece 11. Also, by using the slot-like aperture 54a, most stray light is prevented from reaching the wide area detector beneath the ramp extension 54 and essentially only light from the hooded light source 67 reaches the wide area detector.

Positioned along third ramp 57 is a low-mass gate 71 which pivots about a pivot axle 72. The gate normally is in a closed position wherein coins are shunted off to a reject chute in the direction of direction arrow 73 (coins actually fall on the other side of the chassis piece 11, not on the side visible in FIGS. 5A and 5B). With the gate in its normally closed position, coins traveling down ramp 57 impinge on the gate 71 and bounce through reject exit door 74.

The magnetic coils operate to sense the metallic signal out of the coins as follows. The coils are placed as close to the coin path as possible to allow the coins to pass very close to the magnetic field. To ensure consistent position and orientation, the coin path is tilted. The coin can roll or slide by the sensor and the output from the sensor is essentially unaffected thereby.

The coils are operative for measuring the conductivity of the surface material from the coins.

FIG 6 shows the general period of operation of the magnetic coils in blocked, schematic form.

FIG. 7 shows the outputs measured from the coils in raw form, demodulated, and after a low pass filter. As the coin passes by the coil sensor, a change in the inductance and in the "Q" value occurs that is proportional to the surface current in the coin. Most coins cause the value

to decrease, but metallic objects that have magnetic properties exhibit an increase in inductance, making the signal actually increase. The circuit is tuned such that the amplitude of the signal coming out of the coil is in the sloped part of the reactance curve; therefore, changes in inductance cause a corresponding change in the amplitude of the oscillator sine wave when ran across the inductor. That is, the signal "E-out" is demodulated with a diode demodulator, then a low pass filter rolling off around 400 hz to keep the effects of coin speed to a minimum. The resulting signal is fed to analog-to-digital (AD) converter for the main controller to use with the diameter and thickness information for rejection of improper coins or slugs. This technique has the advantages of low cost, being independent of coin speed and acceleration, and is used only when needed, thereby lowering the power requirements. It is also very temperature tolerant and humidity resistant and is very repeatable from one unit to the next.

The coin validation apparatus is microprocessor controlled. In fact, two microprocessors are used and located on the printed circuit board. The smallest (least powerful and least power consuming) microprocessor serves as an entry detector. It receives signals from the entry sensor and when it detects that a coin has entered the coin validator, it sends a signal to the larger microprocessor (the main controller). This causes the main controller to power up (it normally lies in a dormant state to conserve power). Once the main controller is powered, it begins gathering data electronically from the sensors indicating the material composition, the diameter, and the thickness of the coin. It then analyzes the gathered data from these tests to determine whether to accept the coin or reject it. Thereafter, baseline values are run using the same sensors without a coin present to calibrate the sensors and prepare them for the next coin. The main controller then powers down after the coin exits the scanner. The self-calibration compensates for environmental changes, such as a change in temperature. This allows the scanner to adapt to its environment, even if its environment goes through large changes in temperature, humidity, etc.

The coin validation apparatus is a coin testing device used for accepting authentic coins and rejecting slugs. It performs a series of tests that gather data electronically and compare the data to pre-established criteria. The validation apparatus has the ability to store up to 16 coin sets, of which 8 can be active at any one time. In operation, a coin enters the coin

validation apparatus through entry slot 31. Once the coin enters the coin validation apparatus, the entry detector detects the presence of the coin and sends a signal to activate the large microprocessor (the main controller). The coin next travels along a track where three tests are performed to verify that the coin is authentic. Firstly, test data is gathered using the magnetic coils to establish a metallic signature (metal composition) of the coin. This is done using the two coils, such as coil 47. These coils create a magnetic field and when the coin passes through the field, it creates a disturbance. The disturbance is analyzed and compared with known disturbance patterns for known, valid coins. (NOTE: If any parameter does not match, the unit then powers down and the coin is rejected by default.) Secondly, information is gathered about the diameter of the coin and the possibility of a hole being in the coin. The coin passes the diameter sensor which uses the light emitting diodes and the half-cylindrical reflector along with the wide area detector (solar cell). The solar cell collects the amount of infra-red light from the diodes as the coin passes and is compared with known data for established, valid coin types.

The third test involves gathering information about the thickness of the coin. Again, infra-red light from the diode in the thickness sensor is collected by the wide area detector.

Of course, the thicker the coin, the greater the amount of light that is blocked. The amount of light collected on the wide area detector is compared with stored criteria for established coins.

If the data gathered is within the range of pre-existing criteria, the coin is accepted as a valid coin. If so, the main controller sends a signal to the electromagnet to open the gate 71.

The gate is then opened by the electromagnet to accept the coin. The coin then passes the gate and is detected by the exit detector. The exit detector generates a signal that informs the main controller that the coin has existed the scanner. The main controller then calibrates the sensors to establish a new baseline for the current, local conditions and then powers down.

As the coin moves by the diameter detector, the light received by the large area detector is reduced in proportion. The maximum reduction represents the diameter of the coin, as the maximum reduction occurs when the coin's maximum diameter passes by the slot. The microprocessor controlling the system then can sense the minimum detector output and store the diameter of the coin.

This module also allows the system to sense the presence of holes in coins. The hole is easily detected to allow the system to know the hole is present. This information can be utilized to reject all coins with holes, or the accept coins with holes in those countries that have coins with holes. As the coin passes over the detector aperture 19, the wide area detector senses the amount of light that is blocked, which is proportional to the thickness of the coin. The microprocessor reads the signal and saves the minimum value of the light received, which is proportional to the thickness of the coin. The microprocessor also controls the light source and can therefor calibrate the module before reading the thickness value of the coin. This allows compensation for any variations due to temperature, humidity, or aging of the light source or detector.

If the coin falls outside the established criteria, the coin is rejected by simply allowing the gate to remain in its closed position, and when the coin encounters the gate, it is knocked off track and rejected.

The coin validation apparatus is especially suitable for handling large coins. The maximum coin size of a commercial embodiment of the present invention is 35 millimeters in diameter and 4 millimeters in thickness. Moreover, the coin validation apparatus is particularly adept at preventing coin jams. The three main features that prevent coin jams are a steeply angled track, one main track (as opposed to multiple possible tracks), and only one moving part (the gate). The steeply angled track reduces coin jams by accelerating a coin at a rate that reduces the chances of the coin stopping. The feature of having only one main track reduces coin jams by not diverting the coin into several different tracks which could result in a coin hanging up at such a juncture. The feature of one moving part (the gate) reduces coin jams by reducing the number of moving parts that can possibly obstruct the coin' s path.

COIN ESCROW DEVICE FIGS. 8 and 9 show an escrow apparatus 1010 for use in the pay telephone according to a first preferred form of the invention. The escrow apparatus 1010 includes a housing 111, which housing is made up of housing half-portions 112 and 113. The housing half-portions 112

and 113 are each made of molded plastic and are configured to snap together. To hold the housing halves together, snaps 116-119 and some additional unshown snaps are provided.

The housing includes a lower door 121 positioned within the housing and which defines an upper coin hopper 122. The door is movable between an escrow position (shown in FIG. 9), a coin acceptance position, and a coin return position. The door 121 includes a flat upper surface 123 and a cam track 124 at the underside thereof. The lower door also includes elongate guide pins 126 and 127 at the outer ends thereof.

A pivotal support member 131 is pivotally mounted to the housing 111 about a pivot axle 132 which rides in a pivot bore 133. At an upper end of the pivotal support member 131 a cam portion 134 is formed and rides within the cam track 124 to translate pivotal motion of the pivotal support member 131 into pivotal motion of the lower door 121. The pivotal support member 131 also includes a crank pin 135 for engagement with an actuator (not shown in FIG.

8 or FIG. 9). The crank pin 135 rides within an arcuate track 137 whose radius of curvature is matched to the distance of the crank pin 135 from the center of the pivot axle 132.

The guide pins 126 and 127 at the ends of the lower door 121 ride in pivot tracks 141 and 142 and guide tracks 143 and 144. As can be seen from FIG. 9, the pivot tracks 141 and 142 are much shorter and have a tighter curvature than the guide tracks 143 and 144. The effect of this difference is that as the pivotal support member 131 is moved in one direction or the other, one end or the other of the door 121 moves within its associated pivot track and is ultimately limited thereby, while the other end of the door swings about the first end within the longer, less curved guide track.

The housing half-portion 113 of the housing 111 also includes fixed pivot points 146 and 147 which also act as positive stops to limit upper movement of the door 121 as it is brought to its escrow position of FIG. 9. As the door is pivoted one way or another by movement of the pivotal support member 131, the door 121 is pivoted about one or the other of these fixed pivot points and also slides thereby somewhat.

The housing 111 also includes coin chute surfaces, such as surfaces 148 and 149 which help define a coin acceptance chute and coin return chute.

The door can be operated to move between its escrow position (shown) and its coin acceptance and coin return positions by selective operation of a push-pull solenoid (unshown).

A single solenoid can be used or, as shown in Fig. 10, two (2) solenoids can be employed.

As the door moves from an escrow position to a coin return position, the guide pins attached to the ends of the door move in quite different paths, with one guide pin moving only within the small pivot track associated therewith, while the opposite guide pin of the door swings through the longer guide track opposite thereof. To return the door from the coin return position to the escrow position, the movement is simply reversed.

This construction has numerous advantages. For example, the inboard pivot points allow the door to be easily returned to its home position (the escrow position). Also, the weight of the coins atop the door assists the door in moving to a coin return or coin acceptance position, rather than retarding such movement as is typical in the prior art. Also, this apparatus has very few moving parts, increasing the reliability and ruggedness thereof. Furthermore, because the pivotal support arm 131 is vertical and perpendicular to the door 121 in the escrow position, to move the door to one of the other positions, the pivotal support arm does not have to lift the door (and the coins).

FIGS. 10 and 11 show another version of the coin escrow apparatus. The coin escrow apparatus 1010A is shown as part of a larger assembly 200. The assembly 200 includes a collector adapter 201 for delivering coins from the coin escrow apparatus 101 0A to a collection box (unshown). The assembly 200 also includes a coin reject adapter 1022 which is attached to and cooperates with a refund adapter 203. The assembly 200 also includes an input adapter 204 for receiving coins from an upper part of the pay telephone and delivering them to the coin escrow apparatus 1010A. The adapters 201-204 are each removably mounted to housing 211 of the escrow apparatus 1010A. Thus, to provide an escrow assembly 200 to work in a certain different type of pay telephone, different style adapters are used. In this way, one coin escrow apparatus design can be made to work with pay telephones made by different manufacturers.

The assembly 200 also includes a flag and micro switch arrangement, as is conventional in the prior art. Included therein is a flag axle or flag shaft 205, a flag 206, a flag reset tab 207, a microswitch 208, and a microswitch actuator 209 attached to the flag shaft 205. A flag such as this typically is used in existing phone configurations and it is provided in the illustrative

embodiment to show how the escrow unit can be used to replace existing escrow units in existing telephone applications. Such a flag arrangement is not necessary when using electronic coin discriminators (see Fig. 4A) or with prior so-called "smart" telephone arrangements. With the flag in its normal upright position, it holds the microswitch open. When the central office samples the output from the microswitch, and sees that it is open, this is an indication that no coin is present in the hopper. When a coin is dropped into the hopper, the flag is set by a trigger pivot arm (unshown) to indicate the presence of a coin. The escrow unit itself does not know what coinage is present, only that at least one coin is in the escrow unit hopper. The operation of the flag and the microswitch then informs the central office (or smart phone controller) that a refund will be required if the call is not completed.

FIG. 12 and FIG. 13 show the coin escrow apparatus 1010A in greater detail. As shown, the coin escrow apparatus 101 0A includes a housing 211 which is made up of housing half portions 212 and 213. The half portions 212 and 213 are bolted together using fasteners, such as threaded screw 214.

The housing 211 defines a large volume coin hopper indicated generally at 216, which is defined by lower door 221, lateral sidewalls 217, 218, and front and back sidewalls 219 and 220. The coin hopper 216 has inside transverse dimensions of 44 mm. from lateral sidewall 217 to lateral sidewall 218, 38 mm. from front sidewall 219 to rear sidewall 220, and is more than 24 mm. deep. With this construction, the coin escrow mechanism is well-suited for known coins up to at least about 35 mm. in diameter. Furthermore, this allows the coin hopper to hold a large volume of coins, such as for long distance or international calls. Moreover, despite the presence of larger, heavier coins, and the presence of more of them, the coin escrow mechanism reliably resists self-actuation for reasons that will be described more fully below.

The lower door 221 includes a central flat upper surface 223 and front and rear cam tracks such as cam track 224. The lower door 221 also includes elongate guide pins 226 and 227 at the outer ends thereof.

A pivotal support member 231 is pivotally mounted to the housing 211 about a pivot axle 232 which rides in a pivot bore 233. In addition to the pivot axle 232, the pivotal support member 231 includes a cam portion 234 and a web portion 235 extending between the cam portion 234 and the pivot axle 232.

A magnet 237 is permanently placed in an end of the cam portion 234 and a corresponding magnetically responsive metal element (e.g., steel) 238 is permanently placed in the housing half portion 212. The purpose of the magnet 237 and element 238 is to help return and maintain the pivotal support member 231 in a vertical orientation, centered halfway between the ends of the lower door 221. This magnetic centering means also provides some dynamic damping.

The elongate guide pins 226 and 227 ride in pivot tracks 241 and 242 and guide tracks 243 and 244. (See also FIGS. 14-16.) As best seen in FIG. 13 and in FIG. 16A, the very end portions ofthe guide pins which are received in the pivot tracks and guide tracks are oval-shaped, rather than round, to provide a greater contact surface for contacting the tracks. Also, the minor axis of the oval-shaped guide pins is substantially less than the width of the pivot tracks and guide tracks so that the guide pins are loosely guided therein.

Referring now to FIGS. 12-15, it can be seen that the pivot axle 232 includes drive flats formed on the ends of the pivot axle for receiving a rocker arm 246 on one end and a return arm 247 on the opposite end. The return arm 247 is used in conjunction with a return spring 248 and a return spring mounting post 249 to help urge the return arm 247 into a vertical, upright orientation. In this way, the return spring 248 helps to return the lower door 221 to its escrow position. Also, once the return arm 247 manages to urge the lower door 221 to anywhere near its horizontal escrow position, the magnetic centering means 237, 238 help to stabilize the door in the escrow position and to keep it completely closed. In this way, the apparatus quickly and easily returns to an equilibrium state in which the lower door 221 is in its horizontal, escrow position and the pivotal support member 231 is in its upright position for supporting the lower door.

As best seen in FIGS. 12 and 13, the rocker arm 246 couples the pivot axle 232 of the pivotal support member 231 to first and second solenoids 251 and 252. For example, the rocker arm 246 is coupled to the plunger 253 of the solenoid 251 using a clevis pin 255. The plunger 254 of solenoid 252 is similarly coupled to the rocker arm 246 by an unshown clevis pin.

Moreover, the clevis pins are longer than merely necessary to couple the plungers to the rocker arm and extend rearwardly from the plungers in order to trip a flag reset arm 257 in order to extend a flag reset element 258. The solenoids 251 and 252 are powered using electrical leads,

such as electrical leads 261-264, by connection to a suitable electrical control system. Each of the solenoids is a push/pull solenoid so that the apparatus can be operated even if one of the solenoids or its associated circuitry should fail.

Still referring to FIGS. 12 and 13, the housing 211 includes adapter mounting bars, such as adapter mounting bar 266. The adapter mounting bar 266 is made up of two halves, 266a and 266b. Mounting bar half 266a is integrally molded with half portion 212 of the housing, while mounting bar half 266b is integrally molded with the other housing half portion 213. Adapter mounting bar 266a includes a female portion in the end thereof, while adapter mounting bar half portion 266b includes a male portion in the end thereof for mating engagement therewith when the housing is put together. In this way, some added rigidity is afforded to the adapter mounting bar 266. While FIG. 12 shows an adapter mounting bar 266 on the one side of the housing, another adapter mounting bar (unshown) is positioned on the opposite side of the housing.

The adapters are mounted to the housing using these adapter mounting bars. For example, adapter 201 includes a curved foot portion 267 which is adapted to hook over the adapter mounting bar 266. The adapter 201 also includes a pair of upper spaced apart mounting flanges 268 and 269 each having a mounting hole extending therethrough. With the foot 267 slipped over the mounting bar 266, the adapter is swung upwardly until the flanges 268 and 269 straddle corresponding flanges 271 and 272 of the housing 211. The adapter 201 is then secured in place using a threaded fastener, such as threaded fastener 214 (obviously, if this fastener already is in place before the adapter 201 is to be mounted, the threaded fastener 214 should be removed). In this way, the adapters are removably mounted to the housing 211. Likewise, the input adapter is slipped down over the hopper 216 and it includes flanges for straddling the same flanges 272 and 271 ofthe housing and is secured in place along with the side-mounted adapters.

FIGS. 1 6A and 1 6B show how the sidewalls of the housing in the region of the coin hopper overhang and partly shroud edge portions of the door 221. In this way, coins, such as coin C of FIG. 16A, are prevented from slipping into the space between the sidewalls and the shoulder at the transition between the raised upper surface 223 of the door and the lower outer surfaces, such as surface 222. A lower portion 261 of the lateral sidewalls, such as sidewall 217, is rounded and acts as a fulcrum about which the door 221 pivots. Lateral sidewall 218 has a similar fulcrum. In this regard, the rounded shoulder or transition between the upper surface 223

and the lower surface 222 engages and cooperates with the rounded fulcrum to facilitate the pivotal motion of the door. This also tends to help center the door between the fulcrums.

In addition to accepting large coins, one advantage of the novel escrow apparatus is that very little force is required to activate or trigger the door using the pivotal support member, while at the same time the apparatus resists self-actuation from the weight of coins resting on the door.

Indeed, it takes only a very small motion of the pivotal support member 231 to trigger the door to open one way or the other. In this regard it is very helpful that the door does not have to lift the coins in order to move one way or another. Movements as small as one-eighth of an inch of the cam portion 234 from the centered position trigger the door and allow the weight of the coins above the door to help force the door open and to allow the coins to pass therethrough. This allows the apparatus to be operated at very low power levels, which is advantageous since there may not be much power available over the telephone line to power this device. Thus, pivotal support member 232 is operable for supporting the lower door in its escrow position substantially only when the pivotal support member is vertical (and therefore centered between the ends of the lower door).

COIN RETURN DEVICE FIG. 17 and 1 7A show a coin return apparatus 1014 for use in the pay telephone of the invention. The coin return apparatus includes a housing which defines an upper hopper 301. The housing is configured to be front mounted in a pay telephone and mounted beneath a coin validation mechanism. The housing defines an interior opening for receiving a revolving door (movable door means) 302. The revolving door 302 acts similarly to an airlock in that it prevents direct access from the outside of the pay telephone to the coin hopper 301. This prevents a vandal or thief from passing a foreign object up into the coin hopper, such as to stuff the coin hopper for subsequent theft. As seen in FIG. 17, the revolving door 302 is roughly in the shape of one-half of a circle. In this way, depending upon the rotational position of the door, the door 302 can occlude a space or passageway or provide access to a space or passageway.

A trap door 303 is positioned at the bottom of the coin hopper 301 for engaging the solid portion of the revolving door 302. The trap door 303 prevents the reverse flow of foreign objects or coins and prevents explosive forces from being carried along through the coin hopper and back

up into the coin validation unit above. The trap door 303 is secured to, and pivots with, a blocking door 304 which operates to retain foreign objects (stuffed material). The blocking door 304 is pivoted by a pivot pin 304a and its pivotal motion is limited by a slot 304b and a pin 304c.

The blocking door has vent holes formed therein to allow explosive gases and explosive forces to pass therethrough and prevent damage.

A string cutter 305 is provided at a lower portion of the coin hopper 301 generally adjacent the trap door 303 (with the trap door in its closed position as shown in FIG. 17). The string cutter 305 operates to cut strings which may be used by vandals or thieves in an attempt to drag stuffing material back up into the coin path.

The coin return chamber 306 includes concentric grooves (with lands formed therebetween) formed in the housing. These grooves and lands are also formed in the solid portion of the revolving door. These grooves and lands prevent pins from being used to jam the revolving door and also help keep coins from inadvertently jamming the revolving door.

The housing includes a slot or deep notch 307 for allowing the coin return to be slipped into position in a pay telephone, the coin return being installed from the front of the telephone housing. The coin return housing also includes a small hook 307a for engaging a face portion of the pay telephone housing and a flange 307b for engaging another portion of the face of the pay telephone housing.

The revolving door 302 also includes a finger grip slot 308 for manual user operation of the revolving door. Furthermore, the revolving door 302 includes a return spring 309. The revolving door pivots about a pivot axle or pivot pin 310. Still referring to FIG. 17, one can see that the finger grip slot 308 allows the user to rotate the revolving door 302 in a counterclockwise direction, and that the return spring 309 operates to return the revolving door 302 in the clockwise direction.

Operation of the coin return is quite stralghtforward. In use, a user would insert a finger into the finger slot of the revolving door and rotate the door downwardly, allowing coins to fall into the revolving door chamber. Thereafter, the user would release the revolving door, allowing the return spring to return the revolving door to the position shown in FIG. 17. The user would then reach a finger or fingers into the chamber to retrieve coins deposited therein.

The coin returnjust described accepts coins as large as 35mm and is resistant to "pinning" in which jam pins and other objects otherwise would be inserted alongside the revolving door so that the user cannot operate it. The coin return is also resistant to "stringing" in which a string is tied to a coin and the coin is inserted into the pay station to allow it to be rejected and then stuffing material is tied to the coin end of the string and dragged back up into the coin path. The coin return also is resistant to simply stuffing of material up into the hopper and to stuffing by fireworks.

In accordance with a second preferred form of the coin return, FIG. 18 schematically displays a tamper-resistant coin return device 101 4A mounted within a pay telephone 1000. The coin return device 1014A, viewed from its right side, comprises a housing 404 having an entrance chute portion 406 (also referred to herein as the entrance chute 406) which resides partially beneath one end of a coin return chute 1024 and extends, from the remainder of the housing 404, in a generally upward and rearward direction. The other end of the coin return chute 1024 connects to a coin escrow device. The coin return chute 1024 defines a channel 412 extending therein which descends within the coin return chute 1024 to direct return coins along a portion 414, indicated by arrow 414, of a coin return path 415 into a first, uppermost opening 416 of the entrance chute portion 406 of the coin return device 1014A. A coin reject chute 1022 descends within the pay telephone 1000 between a coin validator device at an upper end (not visible) and connects to the coin return chute 1024 at a lower end 420 which is elevationally above the entrance chute 406 of the coin return device 1014A. The coin reject chute 1022 defines a channel 422 therein which directs return coins along a portion 424 of the coin return path 415 into channel 412 of the coin return chute 1024.

The housing 404 ofthe coin return device 1014A also has a flange 430 which defines a discharge opening 432 therethrough. The flange 430 has a first face 434 which is visible when the pay telephone 1000 is viewed from its front and a second face 436 which resides adjacent to and partially overlaps a front face plate 438 of the pay telephone 1000. The flange 430 and the portion of the housing 404 near the flange 430 cooperate to hold the coin return device 1014A within a hole 440 of the front face plate 438 of the pay telephone 1000. Note that the flange 430 and the portion of the housing 404 near the flange 430 define a hook-like cut-out 442 which receives a portion of the front face plate 438 of the pay telephone 1000 and aids in securing the

coin return device 1014A to the pay telephone 1000. The housing 404 additionally has a notch 444 which temporarily receives a portion of the front face plate 438 near the top of hole 440 during installation of the coin return device 1014A, through hole 440, from the front of the pay telephone 1000.

Between flange 430 and the entrance chute 406, the housing 404 defines a chamber 450 therein which has a substantially circular shape when viewed from a side of the coin return device 1014A. The chamber 450 communicates, at appropriate times during operation of the coin return device 1014A as described below, with the discharge opening 432 and a second, lowermost opening 452 of the entrance chute 406 defined by the housing 404. The entrance chute 406 and the portion of the housing 404 about the chamber 450, during operation, generally direct return coins along portions 454,456, indicated respectively by arrows 454, 456, of the coin return path 415 through the coin return device 1014A for subsequent removal by the user via the discharge opening 432 and portion 458 of the coin return path 415.

Referring now to FIGS. 19 and 20, the coin return device 1014A further comprises a movable, revolving door 470 which resides within the chamber 450 and which is rotatable within the chamber 450 (i.e., in the clockwise and counterclockwise directions indicated by arrows 451, 453, respectively), relative to an axis 472 extending between sides 474, 476 of the housing 404 and through chamber 450. The revolving door 470 has a core portion 478 which extends between sides 480, 482 of the revolving door 470 and which defines a bore 484 which also extends between sides 480, 482. A rod 486 extends in the direction of axis 472 within the bore 484 and through holes 488, 490 defined, respectively, by sides 474, 476 of the housing 404. A spring 492 wraps about the rod 486 and biases the revolving door 470 relative to the housing 404 in a first position, shown in FIGS. 19, 20, where the chamber 450 and the discharge opening 432 are in communication and where the chamber 450 and the second opening 452 of the entrance chute 406 are not in communication.

The coin return device 1014, according to the preferred embodiment, further comprises a folding door 500 and a trap door 502. The folding door 500, as displayed in FIGS. 19 and 20, resides within the entrance chute 406 to cover and uncover the second opening 452 of the entrance chute 406. The folding door 500 includes first, second, and third segments 504, 506, 508 which reside between sides 474, 476 of the housing 404. The first segment 504 has a first

end 510 and a second end 512 distant from the first end 510. The first end 510 defines an axis 514 extending therethrough and defines bores 516, 518 about the axis 514. A rod 520 extends through bores 516, 518 and between recesses 522, 524 defined, respectively, by sides 474, 476 of the housing 404 to position the first segment 504 of the folding door 500 and to enable rotation of the first segment 504 relative to axis 514. Similar to the first end 510 of the first segment 504 ofthe folding door 500, the second end 512 ofthe first segment 504 defines an axis 526 extending therethrough and defines bores 528, 530 about axis 526.

The second segment 506 of the folding door 500 defines a tongue 531 portion which is received within a fork portion 532 of the first segment 504. The tongue portion 531 defines an axis 534 extending therethrough and a bore 536 extending therethrough about axis 534. As seen in FIG. 21, axis 526 ofthe second end 512 ofthe first segment 504 coaxially aligns with axis 534 of the second segment 506 of the folding door 500. A rod 538 extends within bores 528, 530 of the first segment 504 and within bore 536 of the second segment 506 to couple the first and second segments 504, 506 and to enable rotation of the second segment 506 between housing sides 474, 476 about axes 526, 534. The second segment 506 of the folding door 500 also has a fork portion 540 which defines an axis 542 extending therethrough and which defines bores 544, 546 about axis 542.

The third segment 508 of the folding door 500 has a fork portion 550 which defines an axis 552 extending therethrough and bores 554, 556 about the axis 552. The fork portion 550 of the third segment 508 resides between the forks of the fork portion 540 of the second segment 506 with axes 542, 552 in coaxial alignment. A rod 558 extends within bores 544, 546 of the second segment 506 and within bores 554, 556 of the third segment 508 to couple the second and third segments 506, 508 and to allow rotation of the second and third segments 506, 508 between housing sides 474, 476 about axes 542, 552. A spring 560 resides about axes 542, 552 and biases the second and third segments 506, 508 of the folding door 500 in a first orientation, as seen in FIGS. 19 and 20, where the second and third segments 506, 508 lie within a common plane 562.

The third segment 508 of the folding door 500 has an end 564 distant from bores 554, 556 which is proximate the trap door 502 when the revolving door 470 is in its first orientation relative to the housing 404.

The trap door 502, as seen in FIGS. 19 and 21, rotatably couples to the entrance chute 406 of the coin return device 1014A near the second opening 452 of the entrance chute 406. The trap door 502 comprises a panel 570, extending between trap door ends 572, 574, which aligns with a rear portion of wall 576 of the entrance chute 406 and resides within opening 577 of the housing 404 when the trap door 502 is in its closed position as illustrated in FIGS. 19 and 20.

At end 572, the trap door 502 has a forked portion 578 which defines an axis 580 therethrough.

The forked portion 578 defines bores 582, 584 which extend about axis 580. The entrance chute portion 406 ofthe housing 404 defines an axis 588 and bores 590, 592 about axis 588. A rod 594 extends within trap door bores 582, 584 and within entrance chute bores 590, 592 to couple the trap door 502 to the housing 404 and to enable rotation ofthe trap door 502 relative to colinearly- aligned axes 580, 588 in the clockwise and counterclockwise directions indicated, respectively, by arrows 595, 596. In its closed position, end 574 of the trap door 502 resides slightly within the second opening 452 ofthe entrance chute 406. A spring 598 biases the trap door 502 relative to the entrance chute 406 to maintain the trap door 502 normally in its closed position.

According to a method of the preferred embodiment, the coin return device 101 4A defines, as seen in the schematic view of FIG. 22, a first orientation of its components prior to interaction between the pay telephone 1000 and a user of the pay telephone 1000 (i.e., at a first time). In the first orientation, the revolving door 470 ofthe coin return device 101 4A resides in housing 404, with its second notch 658 oriented near the top of the discharge opening 432, with a portion of its outer wall 652 entirely blocking the second opening 452 of the entrance chute 406 (i.e., thereby making the entrance chute 406 and the coin return chute 1024 non-communicable with the chamber 450 and with the discharge opening 432), and with chamber 450 being accessible to the user through the discharge opening 432. Also, the folding door 500 rests substantially against a portion of the outer wall 652 and the trap door 502 entirely blocks opening 577 of the housing's entrance chute 406. Note that, in the first orientation, the outer wall 652 of the revolving door 470 and the folding door 500 break the coin return path 415 into discontinuous segments (i.e., a first segment including portions 414, 454 of the coin return path 415 and a second segment including portions 456, 458) with only the second segment ofthe coin return path 415 (i.e., and, hence, return coins within chamber 450) being accessible to a user.

Then, upon insertion of coin(s) into a coin receiving slot of the pay telephone 1000 by the user, the coin validator determines whether each inserted coin is acceptable (i.e., not a slug, not an unacceptable coin of a foreign country, etc.) or not acceptable. If a coin is not acceptable (i.e., and, hence, termed herein as a "rejected coin"), the coin validator directs the rejected coin into the coin reject chute 408 where it falls, under the influence of gravity, through channel 422 along portion 424 of the coin return path 415 and into channel 412 of coin return chute 1004 If a coin is acceptable (i.e., and, hence, termed herein as an "accepted coin"), the coin validator directs the accepted coin into the coin escrow device 410 for temporary storage until either (1) the user's telephone call is successfully completed and the accepted coins are directed toward a coin receptacle (not shown) for storage until collected by a representative of the pay telephone's owner, or (2) the user's telephone call is not successfully completed and the user operates the telephone's coin return lever (not shown) to cause the coin escrow device 410 to release and direct the accepted coins into channel 412 of the coin return chute 1024. Note that together, any rejected coins and any accepted, but released coins (i.e., released by the coin escrow device) which travel through channel 412 of the coin return chute 1024 are referred to herein as "return coins".

Upon introduction into channel 412 of the coin return chute 1024 return coins are guided along a portion 414 of the coin return path 415, in the direction of the arrows, into the entrance chute 406 of the coin return device 1014A through the entrance chute's first opening 416. Once within the entrance chute 406, the return coins collect atop the folding door 500. The user, desiring to recover the return coins, places the tip of a finger through the discharge opening 432 of the coin return device's housing 404 and into the second notch 658 of the revolving door 470.

In response to the application of a, generally, downward tangential force, by the user, to the outer wall 652 in the proximity of the second notch 658, the revolving door 470 rotates in a counterclockwise direction, indicated by arrow 453, about axis 472 of the housing 404. Upon continuing receipt of the, generally, downward tangential force, the revolving door 470 continues its rotation in the counterclockwise direction with the second notch 658 getting increasingly nearer the bottom of the discharge opening 432, with the outer wall 652 of the revolving door 470 blocking increasingly more of the discharge opening 432 (i.e., thereby increasingly blocking user access to the chamber 450 within the coin return device 101 4A through the discharge

opening 432 of the housing 404), and with the outer wall 652 blocking decreasingly less of the entrance chute's second opening 452.

When the user can no longer cause continued counterclockwise rotation of the revolving door 470 (i.e., when the second notch 658 is positioned substantially near the bottom of the discharge opening 432), the components of the coin return device 1014A are positioned in a second orientation, at a second time, as shown schematically in FIG. 23. In the second orientation, the first notch 656 of the revolving door 470 aligns with notch 444 of the housing 304 and a portion of the outer wall 652 entirely blocks the discharge opening 432, thereby rendering the chamber 450, the entrance chute 406, and channel 422 of the coin return chute 1024 inaccessible to the user via the discharge opening 432. Also, the outer wall 652 no longer blocks the second opening 452 ofthe entrance chute 406, and the second and third segments 506, 508 of the folding door 500 extend in a substantially downward vertical direction after having pivoted relative to the first segment 504 due to the removal of support from the outer wall 552 and the combined weight of return coins previously residing atop the door 500 in the entrance chute 506 and the weight of the door 500 itself applying a downward force on the folding door 500. Note that, in the second orientation, the revolving door 470 breaks the coin return path 415 into discontinuous segments (albeit segments comprising different portions than in the first orientation) with portions 414,454,456 (i.e., a first segment) of the path 415 not being accessible to the user through the discharge opening 432 and portion 458 (i.e., a second segment) of the path 415 being accessible to a user. In the second orientation, the chamber 450 is in communication with the entrance chute 406 and channel 422 of the coin return chute 1024, thereby enabling, with the folding door 500 extending downward, return coins to fall into the chamber 450 from the entrance chute 406 and the coin return chute 1024. Note also that should a substantial number of return coins be present within the entrance chute 406 and/or coin return chute 1024, the second and third segments 506, 508 ofthe folding door 570 are pivotable, as depicted in FIG.

24, into recess 668 of the revolving door 470 (i.e., defining a variant of the second orientation of the coin return device 1014A).

Once the user is satisfied that return coins are present within the chamber 450 of the coin return device 1014A the user removes the tip of his/her finger from the second notch 658 of the revolving door 470. In response to removal of the user's finger, spring 492 causes the revolving

door 470 to rotate in a clockwise direction, indicated by arrow 451, about axis 472 of the housing 404 until the revolving door 470 and the other components of the coin return device 101 4A return to the arrangement of their first orientation shown in FIG. 22. During the clockwise rotation of the revolving door 470, the second notch 658 of the revolving door 470 becomes increasingly nearer the top of the discharge opening 432 and the outer wall 652 of the revolving door 470, while blocking increasingly more of the second opening 452 of the entrance chute 406, presses generally upward on the segments 504, 506, 508 of the folding door 500 to return the folding door 500 to its position in the first orientation ofthe coin return device 1014A.

Note that, due, in part, to the sizing, spacing, and spatial arrangement of the components of the coin return device 101 4A and due, in part, to the movement of the revolving door 470 relative to the housing 474, a direct, continuous, uninterrupted, unsegmented coin return path 415 is never present between the discharge opening 432 and the first opening 416 of the entrance chute 406 (i.e., nor between the discharge opening 432 and channel 422 of the coin return chute 408). Because no such continuous, unsegmented coin return path 415 is ever present, the coin return device 101 4A renders it extremely difficult, if not impossible, for a thief to introduce a foreign object into the coin return chute 108 via the discharge opening 432.

Note that the various components of the coin return device 101 4A (including, particularly, the entrance chute first and second openings 416, 452, the folding door 500, the trap door 502, the chamber 450, and the discharge opening 432) are appropriately sized and positioned to enable the coin return device 101 4A to return large coins having diameters (or, other maximum dimensions) of at least 35 millimeters, as well as smaller coins having lesser diameters (or, other maximum dimensions), to a pay telephone's user.

COIN RECEPTACLE COVER FIG. 26 displays a coin receptacle cover 1030, according to a preferred embodiment of the present invention, coupled to a conventional, commercially available coin receptacle box 1032. The coin receptacle box 1032 has a cavity therein for storing coins deposited in the pay telephone and also has a substantially open top through which coins fall into the cavity. Because the design of the coin receptacle box 1032 are well-known to those reasonably skilled in the art, further description of the details of the coin receptacle box 1032 are not necessary herein.

The cover 1030, seen also in the top plan view of FIG. 27, comprises an upper panel 711 which is substantially square in overall configuration and is, preferably, fabricated from steel to resist possible tampering and theft. The upper panel 711 includes four mounting holes, 712a through 712d, near its corners for securing the upper panel 711 atop the coin receptacle box 1032, preferably, by rivets. The upper panel 711 also includes a large, square coin opening 713 therethrough and a lip 715 which extends around the perimeter of the coin opening 713. In the preferred commercial embodiment described herein, the coin opening 713 has a side length, "A", measuring 35 millimeters to enable large coins (including, but not limited to, those coins having a diameter, or maximum dimension, measuring at least 35 millimeters) to pass easily through the coin opening 713 and through the cover 1030.

The upper panel 711 has an arcuate slot 716 which receives a finger 717 extending therethrough. The finger 717 is part of a shutter assembly 720, described below, for covering and uncovering the coin opening 713. The finger 717 engages a portion of the pay telephone (unshown) such that as the coin receptacle box 714 and cover 710 are inserted into the pay telephone, a portion of the pay telephone engages the finger 717 to move it in the direction indicated by direction arrow 718 to cause uncovering of the coin opening 713 by movable door 722 (i.e., translating in an opening direction indicated by arrow 95) until the finger 717 reaches its "open position" (see FIG. 29) at end 96 of slot 716, corresponding to the open position of movable door 722 (described below). Conversely, as the coin receptacle box 1032 and cover 1030 are removed from the pay telephone, the finger 717 is allowed to move back in the direction indicated by direction arrow 719 to cause covering ofthe coin opening 713 by movable door 722 (i.e., translating in a closing direction indicated by arrow 797) until the finger 717 reaches its "closed position" (see FIG. 30) at end 798 of slot 716, corresponding to the closed position of movable door 722. Note that, as seen in FIG. 31, when the finger 717 has rotated into an intermediate angular position (indicated by angle, a3) half-way between ends 796, 798 of slot 716, the movable door 722 has translated into an intermediate position half-way between its open and closed positions, thereby insuring smooth, non-binding operation of the movable door 7227 Referring now to FIGS. 28 - 30, the cover 710 further comprises a shutter assembly 720, of which finger 717 is a part, for covering and uncovering the coin opening 713. The shutter assembly 720 includes an irregularly-shaped actuator arm 721 and a substantially rectangular

movable door 722 (i.e., movable by sliding or by reciprocating linearly). The irregularly-shaped actuator arm 721 includes the finger 717 and a pivoting end 723 having a pivot hole 725 (i.e., for receipt of a pivot pin) therethrough. The actuator arm 721 further includes a rotation stop 724 for limiting clockwise rotational movement of a pawl 736 as described below. The actuator arm 721 also includes a pawl engaging surface 726 for cooperating with the pawl 736 to prevent the actuator arm 721 from being rotated counterclockwise about the center of pivot hole 725 and, hence, about pivot end 723 when the movable door 722 is in its closed position after removal of the cover 710 from a pay telephone. Furthermore, the actuator arm 721 includes a series of ratchet teeth 727 which also cooperate with the pawl 736 to lock the actuator arm 721 in one of several positions in which the movable door 722 is nearly closed. The actuator arm 721 also includes an elongated slot (or guide track) 728 formed therethrough and a curved channel 730 near finger 717 which partially receives rivet boss 780 of lower panel 751 (described below), as seen in FIGS. 28 and 30. An indent 734, opposite ratchet teeth 727, partially receives rivet boss 784 of lower panel 751 (described below) when the movable door 722 is in its closed position and a hole 747 receives an end of a return spring 746 which also connects to the upper panel 711.

Additionally, the actuator arm 721 has an arcuate edge 735 located near the ratchet teeth 727 which engages a latch mechanism 741 described below.

According to the preferred embodiment, the movable door 722, is substantially rectangular in overall shape and resides substantially atop the actuator arm 721 (see FIGS. 28 - 30). The movable door 722 is, preferably, fabricated from steel to resist tampering. Near an edge portion thereof, the movable door 722 includes a connector pin 729 which is slidably received within the elongated slot 728 of the actuator arm 721. The movable door 722 also includes a pair of upper guide pins 731, 732 which cooperate with an elongate, linear guide track 733 to guide the movement of the movable door 722 and to restrict its movement to a linear, reciprocating type of motion. The guide pins 731, 732, the guide track 733, the elongate slot 728, and the connector pin 729 (i.e., the "cooperative elements") cooperate to allow the rotational or pivoting movement of the actuator arm 721 to be converted into linear, reciprocating motion of the movable door 722. Note that the angle of rotation, a, of the actuator arm 721 (about the center of pivot hole 725) has a maximum measure between a first angle of rotation, a,, and a second angle of rotation, 2, which are pre-determined (i.e., fixed) by the amount of movement

of finger 717 possible (i.e., the stroke length pre-determined by the internal components of the pay telephone) during insertion and/or removal of the coin receptacle box 1032 and cover 1030 into/from a pay telephone. Also, note that the maximum dimensions of the cover 1030 (and, hence, the amount of available space for receipt of a door 722) are substantially fixed and/or restricted in order to enable the cover 1030 to cooperate with existing pay telephone housing and coin receptacle boxes 1032. By producing linear, reciprocating motion of a door 722 instead of the rotary motion of a door, as in the prior art, with the limited rotary movement of the actuator arm 721 and within the confined dimensions of a cover 1030, the "cooperating elements" enable the size ofthe door 722 and the coin opening 713 to be substantially larger than doors and coin openings of prior art devices, thereby enabling the cover 1030 of the present invention to accept coins of larger maximum dimension than prior art devices. The acceptance of larger coins is of particular import when using the cover 1030 in pay telephones in countries which may have coins of larger maximum dimension than the coins of the United States. The "cooperating elements" also enable a relatively large coin opening 713 (i.e., larger than those possible with prior art devices) to be completely covered and uncovered, thereby making the entire coin opening 13 available to pass a coin falling toward the coin receptacle box 1032.

The movable door 722 also includes an edge 737 having a beveled portion 738 and an adjacent recessed portion 739. The beveled portion 738 insures that the latch mechanism 741, described below, is appropriately directed into contact with arcuate edge 735 of the actuator arm 721. The recessed portion 739 prevents substantial contact of various parts of the latch mechanism 741 with the movable door 722 when the door 722 is positioned, as seen in FIG. 29, in the open position.

Referring again to FIGS. 28 - 30, a spring-biased pawl 736 is pivotally mounted for rotation between an armed position shown in FIG. 28, a triggered (but unlocked) position shown in FIG. 24, and a triggered and locked position shown in FIG. 30. Furthermore, from viewing FIG. 30, one can readily see that the pawl 736 (and, hence the actuator arm 21 and movable door 722) can be locked in some additional substantially closed positions by engaging the ratchet teeth 727 and the pawl 736. The ratchet teeth 727 and the pawl 736 cooperate to prevent an individual from obstructing the shutter assembly 720 from completely closing (and leaving the coin opening 713 partially or entirely uncovered) as the coin receptacle box 1032 and cover 1030 are removed

from the pay telephone and then subsequently pushing the shutter assembly 720 back open to gain access to the coins contained in the coin receptacle box 714. By the interaction of the ratchet teeth 727 and the pawl 736 shown and described herein, the shutter assembly 720 can be locked in a nearly closed position, thereby preventing the shutter assembly 720 from being forced back open. Once the obstruction is removed, the shutter assembly 720 will continue to the fully closed position shown in FIG. 30, thereby making the cover 1030 tamper resistant. Note that, in order to aid in preventing an individual from forcing open the shutter assembly 720 after the movable door 722 is in the closed position or in a nearly closed position, the moment about the pawl 736 is kept low and the pawl spring tension is kept high.

Operation of the coin receptacle cover 1030 is straightforward. In use, the internal latching mechanism 741 is armed with the cover 1030 removed from its associated coin receptacle box 714, at a central location, by positioning a screwdriver blade into slot 758 of the pawl 736. Then, by counterclockwise rotation of the screwdriver blade (and, hence, counterclockwise rotation of the pawl 736), the pawl 736 engages hook 743 of the latching mechanism 741 to place the cover 1030 in the armed configuration as shown in FIG. 28. The cover 1030 is then replaced and sealed (i.e., with a tamper-evident seal) atop the coin receptacle box 1032. Once the cover 1030 is armed and the cover 1030 and box 1032 are sealed with a tamper-evident seal, the coin receptacle box 1032 and the cover 1030 are given to an individual responsible for installing the coin receptacle box 1032 and servicing a pay telephone in the field.

To collect the money from a pay telephone, a resident coin receptacle box 1032 and cover 1030 are removed from the pay telephone (and replaced with an empty box and cover assembly). The act of removal causes the finger 717 and, hence, the actuator arm 721 of the removed cover 1030 to rotate clockwise about pivot end 723, pawl 736 to rotate clockwise into engagement with rotation stop 724, and movable door 722 to translate into the position shown in FIG. 30.

Engagement ofthe pawl 736 and the actuator arm 721 with the pawl 736 substantially adjacent the rotation stop 724 locks the actuator arm 721 and, therefore, the movable door 722 in a position covering the coin opening 713. The locked unit (i.e., the cover 1030 and coin receptacle box 1032) is returned to a central location with the tamper-evident seal remaining intact, thereby ensuring that no pilferage of coins has taken place. The act of inserting the empty box and cover unit into the pay telephone causes finger 17 and, therefore, arcuate edge 735 of the actuator arm

721 to rotate counterclockwise, about pivot end 723, into contact with the trigger finger 742 of the latching mechanism 741. Upon sufficient rotation of finger 717 and sufficient counterclockwise rotation of the latching mechanism 741, the hook 743 pivots and releases pawl 736 into contact with the actuator arm 721 as depicted in FIG. 29. Rotation of the actuator arm 721 also causes the movable door 722 to translate in the opening direction indicated by arrow 795 into the fully-open position of FIG. 29, where the coin openings 713, 770 are entirely uncovered allowing coins to fall through the cover 1030 and into the coin receptacle box 1032.

The coin openings 713, 770 remain uncovered until the coin receptacle box 1032 and cover 1030 are removed from the pay telephone.

While the invention has been disclosed in preferred form, it will be apparent to those skilled in the art that many modifications, additions and deletions can be made therein without departing from the spirit and scope of the invention as set forth in the following claims.