IE43047B1 - An automatic coin-checking mechanism - Google Patents

Abstract

1523208 Coin-checking mechanism AUTELCA AG 2 Aug 1976 [19 Aug 1975] 32055/76 Heading G4V An automatic coin-checking mechanism is mounted vertically as shown in Fig. 3 and has a coin insertion channel 1 and a coin checking chamber 2. A wall 3 of the channel and chamber is pivotally mounted and is normally positioned in a rest position 311 or a locked position 31. In operation a coin 9 is inserted into channel 1. If it is metallic this is sensed by coil 13 and a run-through signal is produced. If it is non- metallic it passes direct to a return channel 7. The run-through signal operates a pressure device, 22, 23, 24 to move wall 3 from rest position 311 to locked position 31 against the action of leaf spring 21. Wall 3 has a projection 27 that co-operates with stop 28 to hold the coin correctly positioned relative to coils 14 and 15. If no acceptance signal is produced after a predetermined time the pressure device releases wall 3 which is moved to its rest position by spring 21. The "coin" then passes to return channel 7. If there is an acceptance signal a flap moves from a rest position 611 into an acceptance position where plate 34 opens a storage channel 8. Also pin 43 moves into the coin path to prevent further coins entering the checking chamber and second plate 35 is positioned to direct the accepted coin into channel 8. The pressure device releases wall 3 and the coin passes to the storage channel. If another coin has already been inserted pin 43 cannot move to its correct position and after a predetermined time wall 3 is released and the coins pass to the return channel. The flap is moved by a draw device 31, 32, 33 against the action of spring 30. At the end of the channel 8 there is an arrangement such that an accepted coin can be passed to the return channel 7 or to a further store. The channel 8 can contain a multiple of coins. When full counter coil 46 produces a continuous signal that prevents the acceptance of further coins. Plate 34 has a cutting edge that co-operates with a cutting edge on a fixed counter-knife 42. The wall 3 has an angle piece 16 that has a projection 19 that enters chamber 2 to allow a coin to pass to the checking area but prevent return movement.

Description

The invention is more particularly concerned with a mechanism of the type having a coin insertion channel; a checking member, arranged in said channel, of a device which responds to the presence of a metallic body in said channel to produce a run-through signal; a coin checking chamber communicating with the coin insertion channel; a further checking member, arranged in said chamber, of a device which responds to the presence of a coin in said chamber to produce an acceptance signal when the coin is acceptable; and a switch-point connected to the coin check>ing chamber and operative in response to the acceptance signal to distribute the coin into a first channel for acceptable coins or, in the absence of such acceptable signal, into a second channel for unacceptable coins and other bodies.

Coin checking mechanisms are known which have a coin insertion channel with a cross-section which is adapted to accept, with clearance the greatest dimensions of the acceptable coins.

For the coih checking, the coin Channel leads for example through the coil field of an oscillator circuit, whereby upon a predetermined change in the oscillator vibration by virtue of an acceptable coin falling through the coin slot, a coin acceptance signal can be produced.

Xt is further known to associate with a coil of the oscillator circuit a fixed stop which projects in such - 3 a way into the coin channel that it halts a coin-shaped body, which drops through the coin channel and which has the diameter of the acceptable coins, in a predetermined position with regard to the coil, but allows coin-shaped bodies having smaller diameters to pass.

It is further known for a switch-point for the passing-on of the coins and other bodies after they have been checked to be arranged at the end of the coin channel.

In this respect, the unacceptable bodies drop into a channel for unacceptable bodies and the acceptable coins drop into a channel for acceptable coins.

Difficulties arise upon the operation of the known automatic-coin-checking mechanisms more especially through bodies which block the coin insertion channel. The insertion of bodies which are larger than acceptable coins in the case of the known automatic mechanisms can indeed be prevented by corresponding dimensions of the insertion slot.

However, the introduction of, for example, flexible elongate bodies cannot be prevented. Through such bodies the coin channel can be clogged, which leads to interruptions in operation and then requires an expensive dismantling of the mechanism for cleaning of the coin channel. The clogging of the coin channel could basically be avoided or reduced by enlarging the coin channel. In this connection, however, for example upon a coin checking by means of two opposite coils the spacing between the two coils would become too great for a faultless coin checking.

An object of the present invention is, in the case of a coin-checking mechanism having a flat coin-insertion channel, to prevent clogging of the coin channel and to make possible a simple cleaning thereof without causing any impairment of the coin checking function.

According to the present invention there is provided a coin checking mechanism of the type mentioned initially characterised in that a wall bounding the coin insertion channel and the coin checking chamber is mounted so as to be pivotable about an axis along one edge, 3047 - 4 said edge being disposed substantially horizontally when the mechanism is in use, and is connected to a locking device in such a way that, upon the occurrence of a run-through signal it is locked in a position in which it bounds the coin checking chamber at a spacing from a stationary wall, in which locked position a projection protruding therefrom extends into the coin checking chamber in order to keep a coin-shaped body, having the diameter of an acceptable coin and having passed through the coin θ insertion channel and into the coin checking chamber, in a checking position in the coin checking chamber, and the pivotable Wall, after a coin checking is moved to a position of rest in which it has a greater spacing from the stationary wall than the spacing for the coin checking, said position of rest being such as to allow a body to pass Out of the coin checking chamber into the first channel or the second channel in accordance with the position of the switch, point.

The switch-point advantageously comprises a flap θ which is pivotable about an axis parallel to the stationary wall and has a first plate and a second plate, which are arranged in two planes which intersect one another and are offset relative to one another in a direction perpendicular to the swivel axis in such a way that when the flap is in a first offset position the first plate closes the entrance of the first channel and forms a coin guide leading into the second channel and when the flap is in a second position, determined by a coin acceptance signal, the Second plate closes the entrance of the second channel and forms a coin guide leading into the first channel.

Furthermore, the first channel is preferably a storage channel in which several coins can be stored,and at the exit of which is arranged a holding device with a switch-point for the release and return of individual coins ; stored in the storage channel.

With the flap and the first channel designed as a 4304? - 5 storage channel, a separate store and an additional feed channel for the feed of acceptance coins into the separate store become unnecessary.

Thus the mechanism can be designed as a compact, plug-in and easily exchangeable unit which contains a coin checker and a storage part.

Several units, each of which is intended for a different kind of coin, can be arranged in plug-in manner in a block of a cashiering station, whereby a simple ex10 changing of the units for units for other kinds of coins is possible.

One exemplified embodiment of the invention with a switch-point formed by a flap is described in more detail hereinunder with reference to the accompanying drawings, in which:Fig.l shows a front view of coin-checking mechanism in which a pivotally mounted wall is shown folded upwards and the flap is shown in its position of rest, being a view in the direction of arrow I in Fig.3; Fig.2 shows a section taken along the line Il-Il in Fig.l, in which the pivotally mounted wall is omitted and the flap is shown in a second position (acceptance position); Fig.3 shows a side view in the direction of arrow III in Fig.l, in which the pivotally mounted wall is shown in its locked position and the flap is shown in the acceptance position; Fig.4 shows a perspective view in the direction of the arrow IV in Fig. 1, the pivotally mounted wall being omitted and the flap being shown in its position of rest.

The coin checking mechanism, shown in the drawings, has a flat coin insertion channel 1 and a flat coin checking chamber 2 communicating therewith, and which are bounded by two walls 3,4. The wall 3 is mounted so as to be pivotable about a horizontal axis 5. In Fig.l, for better representation, the wall 3 is shown in an upwardlyhinged position designated by 3’ the wall 3 is put in this position 3' upon any necessitated cleaning of the insertion channel 1 and of the checking chamber 2. During operation 3047 - 6 of the mechanism, the wall 3 is put in a locked position shown in Fig.3 and designated by 3' or in a position of rest indicated in dot-da(sh outline in Fig.3, and designated by 3 .

Connected to the coin checking chamber 2 is a switch point flap which forms a deflector. In the position of rest 6 of the flap the coin checking member 2 communicates with a return channel 7 for non-acceptable coins.

In the acceptance position 6' of the flap, the coin checking chamber 2 communicates with a storage channel 8 for acceptable coins 9.

Arranged at the exit of the storage channel 8 is a holding device 10 with a switch-point, designated as a whole by numeral 11, for the release of individual i coins stored in the storage channel 8 for the return thereof.

An insertion slot (not shown) prevents insertion into the coin channel 1 of coin-shaped bodies whose dimensions (diameter or thickness) are greater than the corresponding dimensions of an acceptable coin 9. The width of the coin insertion channel 1 can, through an exchangeable stop 12, be so dimensioned that a coinshaped body whose diameter corresponds to an acceptable coin 9 upon passing through the channel 1 perforce completely masks for a specific time a coil 13 which is arranged in the wall 4 of the coin insertion channel. In the drawings, the stop 12 for the largest acceptable coin is.shown.

The coil 13 is connected to an oscillator circuit (hot shown) for the production of a run-through signal upon being passed by a metallic body. Arranged at the coin checking chamber 2 in each of the two walls 3 and 4 is one of two coils 14 and 15 respectively, which lie opposite one another in the locked position 3' of the wall 3 and which form a part of an oscillatory circuit of an oscillator (not shown) . In the position 3' of the - 7 wall 3, the oscillations of the oscillator may be continued or interrupted depending on the electrical and magnetic properties of a coin-shaped body present between the coils 14 and 15, The oscillator is connected to a circuit (not shown) for producing an acceptance signal, the production of which is dependent upon whether the vibrations of the oscillator are continued or interrupted.

The oscillator circuit with the coils 14 and 15 and the oscillator circuit with the coil 13 collaborate in such a way that an acceptance signal is producable only in the event of a run-through signal having been produced.

At the side of the wall 3 which is remote from the wall 4, an angle piece 16 (Fig.l) is mounted so as to be pivotable about an axis 17. Through an aperture 18 in the wall 3, a bent part 19 of the angle piece 16 extends, in the position 3' of wall 3, into the coin checking chamber 2. The bent part 19 of the angle piece 16 has a foot 20 with a foot surface extending in the position 3' at an angle to the wall 4. In this respect the foot surface has at the top a spacing from the wall 4 which is greater than the thickness of the acceptable coin, whilst its lower part either butts against the wall 4 or is spaced therefrom by an amount which is smaller than the thickness of the acceptable coins. A coin 9 dropping through the insertion channel 1 knocks the foot 20 of the pivotally mounted angle piece 16 out of the coin checking chamber 2. After the passing of the coin, the angle piece 16 returns once more into the original position so that the lower part of the foot 20 prevents the coin from rebounding off a stop 28 or off a projection 27, and also prevents a coin, fastened to a thread, from being withdrawn by means of the thread. The stop 28 is fixed in the mechanism in such a manner, for example by means of a screw, that it may be exchanged for adapting the mechanism to receive any diameter of acceptable coin.

In the position of rest 3 of the wall 3, a bent leaf spring 21 holds the wall 3 in such a way that the 3047 - 8 planes of the walls 3 and 4 extend at an acute angle of, for example 5° relative to one another. Against the force of the spring 21, the wall 3 can be forced towards the locked position 31 by a pressure device which in5 eludes an electromagnet having a coil 22 and a plungertype armature 23. The plunger-type armature 23 is connected, in a manner which is only shown schematically, to a push rod 24 which, upon actuation of the electromagnet, is moved to the right as viewed in Fig.3. In making this movement, the rod 24 presses on a resilient tongue 25 which is fastened to the edge of the wall 3 and which extends beyond the edge. The armature 23 is connected to the oscillator circuit for producing the run-through signal, in such a way that a run-through [_5 signal initiates a pressure action on the wall 3. A distance piece 26 is fastened to the wall 4 in the coin check ing chamber 2. Upon actuation of the armature 23, the wall 3 is forced against the distance piece 26. In so doing the wall 3 is locked in the position 31 in which it bounds the coin checking chamber 2 at a spacing, defined by the distance piece 26, from the wall 4. In this locked position, the Spacing between the walls 3 and 4 and thereby more especially the spacing between the coils 14 and 15 arranged in the walls 3 and 4 is firmly pre5 determined by the distance piece 26. The distance piece 26 is so dimensioned that the spacing of the two walls 3 and 4 or of the two coils 14 and 15 corresponds to the spacing which is necessary for the run-through of an acceptable coin 9 and which is necessary for a coin check) ing operation between these coils.

A metallic body, which has fallen through the coin channel 1, of acceptable diameter and acceptable thickness is held ih the predetermined checking position between the coils 14 and 15, in the locked position 3' of ; the wall 3, by the projection 27 on the wall 3 and the stop 28 fastened to the wall 4. • 43047 - 9 The projection 27 is so dimensioned that it has, in the locked position 3' of the wall 3, a spacing from the wall 4 which is smaller than the thickness of the acceptable coins. In the locked position 3' of the wall 3, the spacing, measured in the plane of the wall 4, of the projection 27 from the stop 28 is somewhat smaller than the diameter of the acceptable coins. A metallic body which has dropped through the coin channel 1 and which is of smaller thickness or of smaller diameter than the corresponding dimensions of acceptable coins is not held back by the projection 27 or by the stop 28, and it therefore drops through the return channel 7, communicating with the coin checking chamber 2 in the position of rest 6 of the switch point flap for non-acceptable bodies.

The switch point flap is movable about an axis 29, upon occurrence of the acceptance signal, from its position of rest 6 into its acceptance position 6', by means of a draw device. The switch point flap is held in the position of rest 6 by a spring 30 (Fig.3). The draw device has an electromagnet with a coil 31 and a plungertype armature 32. The plunger-type armature 32 is connected, in a manner which is shown only schematically, to a draw rod 33 which is pivotally attached to the switch point flap. Upon switching-on of the electromagnet, the switch point flap is pivoted to the left in Fig.3 against the force of the spring 30.

The switch point flap has a first plate 34 which extends in the direction of the flap axis 29, and a second plate 35 which extends at a right angle to the first plate 34 (Figs.4 and 5). The first and the second plates are offset relative to one another in a direction perpendicular to the pivotal axis of the flap. A slot in the wall 4 is associated with each of the plates 34, 35 in such a way that the plates 34, 35 can project upon rotation of the switch point flap, perpendicularly through the wall 4. - 10 The lower edges 38,39 of the wall 3 are, in the locked position 3' flush with corresponding edges of remainder of the mechanism. In this connection in the position of rest 6 the first plate 34 is located behind the second plate 35 in the direction of movement of a coin through the mechanism. The edge 40 of the first plate 34 and the edge 41 of the second plate 35 lie in a common plane which is, in the position of rest 6 of the switch point flap lies in the same plane as the wall 4.

LO In the position of rest 6 of the flap 6, the first plate 34 closes the entry of the storage channel 8 and forms a lower coin guide leading into the return channel 7. The second plate 35 is arranged, in the position of rest 6, behind the wall 4 and thereby does not hinder the passage ,5 of a coin from the coin checking chamber 2 into the return channel 7. In the acceptance position 6', released by an acceptance signal, of the flap 6 the second plate 35 closes the entry of the return channel 7 and forms a lower coin guide into the storage channel 8. The edge 40 of the first plate 34, that is the leading edge in the closing movement, is provided with a cutting edge for the formation of a knife.

Arranged in a slot 36 in the wall 4, is a counterknife .42 whose cutting edge lies in the plane of the upper surface (as seen in Figs. 4 and 5) of the wall 4. In the position of rest 6 of the switch point flap, the first plate 34 butts against the counter-knife 42, so that the cutting edge 40.of the plate 34 engages over the cutting edge of the counter-knife 42. In the acceptance position > 6' the cutting edge 40 of the plate 34 is arranged at a spacing from the cutting edge of the counter-knife 42 which is greater than the thickness of the acceptable coins. Connected to the switch point flap is a pin 43 Which, in the position of rest 6 of the switch point flap is arranged behind the wall 4. In the acceptance position 6 of the switch point flap, the pin 43 extends through a - 11 hole in the wall 4 and a hole in the wall 3 so that it extends through the coin-checking chamber 2 and blocks the coin channel at the transition from the coin insertion channel 1 to the coin checking chamber 2.

Arranged in the storage channel, at a spacing from the slot 36, is a coil 46 of a device (not shown) for the production of a counting impulse (Fig.l). The device is connected to the draw device (31, 32, 33) for the actuation of the switch point flap in such a way that after production of a counting impulse the switch point flap is released by the draw device and is returned by means of the spring 30 into the position of rest 6.

The storage channel 8 and the return channel 7 are bounded by the wall 4 and a plate 47 which is provided with a window 48 in the region of the storage channel 8.

The length of the storage channel 8 corresponds : to a multiple of the diameter of the acceptable coins 9. Arranged at the exit of the storage channel 8 is the holding device 10 with its switch point 11 for the release and return of individual coins stored in the storage channel 8. The holding device 10 with the switch point 11 belongs to a return member 49 and a retaining member 50 which, in the position of rest, are forced by a respective spring against a rear stop. Each of the parts 49,50 is formed at the end of a separate tongue which are actuatable by a respective tongue (e.g. 51), each of which forms an extension of the armature of a magnet system along the lines of a flat-type relay, the coil of which is shown symbolically and is designated by 52. Several coins present in the storage channel 8 are held by a fixed stop 53 on the wall 4 and a plate 54 of the return member 49. Through an actuation of the return part 49, a coin passes into the return channel 7, while the further coins are held by a pin 55 of the return member 49. Through an actuation of the retaining member 50, one of the coins is raised by means of a pin 56 of the retaining member 50 over the fixed stop 53 and passes into a storage container 047 - 12 (not shown). The remaining coins are held hy the pin 56 in the storage channel 8.

The mode of operation of the automatic cashier is described hereinunder for a non-acceptable body and an acceptable coin 9.

In the case of a non-acceptable body made of nonmetallic material, no run-through signal is produced by the oscillator circuit connected to the coil 13. In this way the wall 3 remains in the position of rest 3. The body is not detained in the coin checking chamber 2, since the projection 27 of the wall 3 does not extend into the coin checking chamber 2. The first plate 34 of the switch point flap which is in the position of rest 6 guides the body into the return channel 7. The ; body cannot jam in the coin runway, since the wall 3 is mounted so as to be pivotable. In the case of a metallic non-acceptable body (for example a non-acceptable coin), a run-through signal is produced. The wall 3 is forced by the pressure device (22,23, 24) into the locked position 3' and the body is, if it has the dimensions of an acceptable coin, held by the projection 27 and the stop 28 between the coils 14 and 15 in the coin checking chamber 2. By virtue of the coin checking (e.g. for electrical and/or magnetic metal or alloy properties), no coin acceptance signal is produced and the switch point flap remains in the position of rest 6. The pressure device (22,23,24) releases, after a predetermined period of time, the wall 3 which returns through the force of the leaf spring 21 into the position of rest 3. Thus, the projection 27 swings away from the wall 4 and the body drops into the return channel 7.

An acceptable coin is held in the coin checking chamber 2 in a similar way to a non-acceptable metallic body, for example a non-acceptable coin. By virtue of the coin checking (14, 15) a coin acceptance signal is produced, whereby the draw device (31,32,33) swings the - 13 switch point flap into the acceptance position 61. In this connection, the second plate 35 closes the return channel 7 and the first plate 34 opens the storage channel 8. At the same time the pin 43 thrusts, in the coin travel dir5 ection behind the coin, through the coin pathway and blocks this for subsequent coins. (If a further coin is already located in the coin checking chamber 2, this coin blocks the pin 43 and thus the switch point flap so that this remains in the position of rest 6 and both coins roll, after release of the wall 3, into the return channel 7.) After a predetermined period of time, the pressure device (22, 23, 24) releases the wall 3 and the coin no longer held by the projection 27 rolls on the plate 35 into the storage channel 8. The device, connected to the coil 46, for the production of a counting signal emits a counting impulse which is, for example, registered in a coin telephone and releases the draw device (31, 32, 33) which swings the switch point flap into the position of rest 6. In this connection, the cutting edge 40 of the first plate 34 cuts against the cutting edge of the counter knife 42, so that a coin suspended from a thread is severed.

The coin is held by the blocking device 10 in the storage channel 8. The storage channel 8 can be filled by further acceptable coins as far as the coil 46. A coin which passes into the storage channel 8 and which is held by the already stored coins against the coil 46 releases a counting impulse the duration of which is unlimited. In this way the switch point flap remains in the position of rest 6, so that further inserted coins drop through the return channel 7.

A bent and therefore non-acceptable metallic coin produces a run-through signal. The wall 3 is forced by the pressure device (22,23,24) into the locked position 3 * and the bent coin is (as a result of the deformation) clamped fast between the wall 3 and the wall 4 in the coin insertion channel 1 or at the entrance of the coin checking 047 - 14 chamber 2. Since no coin acceptance signal is produced, the switch point flap remains in the position of rest 6, the pressure device (22, 23, 24) releases the wall 3, after the predetermined period of time, so that it returns into the position of rest 3, whereby the bent coin drops through the coin checking chamber 2 into the return channel

Claims (16)

1. CLAIMS;1. An automatic coin checking mechanism having a coin insertion channel; a checking member, arranged in said channel, of a device which responds to the presence of a metallic body in said channel to produce a run-through signal; a coin checking chamber communicating with the coin insertion channel; a further checking member, arranged in said chamber to produce an acceptance signal when the coin is acceptable and a switch point connected to the coin checking chamber and operative in response to the acceptance signal to distribute the coin into a first channel for acceptable coins or, in the absence of such acceptance signal, into a second channel for non-acceptable coins and other bodies, characterised in that a wall bounding the coin insertion channel and the coin checking chamber is mounted so as to be pivotable about an axis along one edge, said edge being disposed substantially horizontally when the mechanism is in use, and is connected to a locking device in such a way that, upon the occurrence of a run-through signal, it is locked in a position in which it bounds the coin checking chamber at a spacing from a stationary wall, in which locked position a projection protruding therefrom extends into the coin checking chamber, in order to hold a coin-shaped body, having the diameter of an acceptable coin and having passed through the coin insertion channel and into the coin checking chamber, in a checking position in the coin checking chamber, and the pivotable wall, after a coin checking, is moved to a position of rest in which it has a greater spacing from the stationary wall than the spacing for the coin checking, said position of rest being such as to allow a body to pass out of the coin checking chamber into the first channel or the second channel in accordance with the position of the switch-point. 430 47 - 16

2. A mechanism as claimed in Claim 1, in which the switch point comprises a flap which is pivotable about an axis parallel· to the stationary wall and has a first plate and a second plate which are arranged in two planes which intersect one another and are offset relative to one another in a direction perpendicular to the swivel axis in such a way that when the flap is in a first or rest position the first plate closes the entrance of the first channel and forms a coin guide leading into the second channel and when the flap is in a second position, determined by a coin acceptance signal, the second plate closes the entrance of the second channel and forms a coin guide leading into the first channel.

3. A mechanism as claimed in Claim 1 or 2, in which a device for the production of counting impulses is arranged at the entrance of the first channel.

4. A mechanism as claimed in Claim 2 or 3, in which that edge of the first plate of the switch plate flap which leads in the closing movement is designed as a cutting edge which after production of a coin acceptance signal, is arranged at a spacing from a counter-knife which is greater than the thickness of the acceptable coins, which cutting edge after production of a counting impulse butts against the counter-knife in order to sever a supporting thread supporting a coin.

5. A mechanism as claimed in any of Claims 2 to 4 in which the flap is provided with a pin securely connected, and which projects into the coin checking chamber in the direction of run-through of the coin behind the predetermined position of the coin when the second plate of the flap closes the entrance of the second channel,said pin preventing the entry of further coins into the coin checking chamber. - 17

6. A mechanism as claimed in any preceding claim in which an angle piece is mounted so as to be pivotable on the pivotably mounted wall and a part of which, in the locked position of the wall, projects into the coin checking chamber and has a foot with a surface which extends at an angle to the stationary wall plane and which has, in the direction of travel of the coin, at the rear a spacing from the stationary wall which is greater than the thickness of the acceptable coins whilst the front abuts against the stationary wall or is spaced therefrom by a spacing which is smaller than the thickness of the acceptable coins.

7. A mechanism as claimed in any preceding claim, in which the pivotably-mounted wall is held in its position of rest by a spring.

8. A mechanism as claimed in any of claims 1 to 4, in which the length of the first channel corresponds to a multiple of the diameter of the acceptable coins, and a coin holding device is arranged at the exit of the first channel, said holding device having a switch-point for controlling the release of individual coins stored in the first channel.

9. A mechanism as claimed in Claim 8, in which the holding device with the switch-point is actuatable by a magnet system in the form of a flat-type relay.

10. A mechanism as claimed in Claim 1, in which in addition to the projection of the pivotable mounted wall, a stop is provided on the stationary wall in the checking chamber in order to hold, between said projection and said stop, a coin-shaped body of acceptable diameter which has dropped through the coin insertion channel, in the checking position. 3047 - 18

11. A mechanism as claimed in Claim 10, in which the stop is exchangeable, for the purposes of adapting the mechanism to receive any diameter of acceptable coin.

12. A mechanism as claimed in any preceding claim, in which arranged in each, of the two walls is a coil which, in the locked position of the pivotably mounted wall, lie opposite one another and form parts of an oscillatory circuit for the production of a coin acceptance signal, in such a way that the oscillations of the oscillatory circuit start or cease in response to presence of an acceptable coin, the production of an acceptance signal being dependent on whether the oscillations start or cease.

13. A mechanism as claimed in Claim 3, in which the device for the production of a run-through signal and the device for the production of a counting impulse each contain a coil.

14. A mechanism as claimed in any preceding claim, in which the projection of the pivotably mounted wall, in the locked position of said wall, is spaced from the stationary wall by a dimension which is smaller than the thick ness of the acceptable coins.

15. A mechanism as claimed in any preceding claim, designed as a modular unit adapted to plug into a block.

16. An automatic coin-checking mechanism substantially as herein described with reference to and as illustrated in the accompanying drawings.