US1890380A - Coin testing apparatus - Google Patents

Description

Dec. 6, 1932;

F, W. HOBAN COIN TESTING APPARATUS Filed April 24, 1929 3 Sheets-Sheet iz I llllll Q ATTORNEYS Dec. 6 1932. F. w. HOBAN C( JIN TESTING APPARATUS Filed April 24, 1929 3 Sheets-Sheet 2 llilll Mm um ill m INVE?) @r lle/a olafl ATTORNEYS Dec. 6, 1932. H BAN 1,890,380

COIN TESTING APPARATUS FiledApril 24. 1929 s Sheets-Sheet 3 I I -I- I I I I I I l I l l ,l

I I I 1,!

V NTOR ATTORNEYS 'Patented Dec. 6, 1932 UNITED STATES- IAIBFIELD W. EOBAN, OF NEW YOR K, N. Y ASSIG-NOR TO 'FAIRFTELD SPECIALTIIB PATENT OFFICE CORPORATION, OF YORK, N. Y., A CORPORATION OF NEW YORK COIN TESTING APPARATUS My invention relates to improvements in means for and methods of testing coins, tokens, or like devices to determine whether the same are genuine or spurious, and the invention has for its object more particularly to provide a novel method for electrically detecting or indicating the presence of spurious co ns, tokens or like devices and distinguishing therebetween and the genuine to enable rejection of such spurious devices, and, in performing said method, to provide a simple, efiicient, and reliable apparatus which operates automatically to accept the genuine pieces or devices and to reject the spurious or counterfeit ones.

Another object of the invention is to provide an apparatus of the character specified which depends for operation in accepting.

a genuine coin or token upon a property or quality of such genuine coin or device not possessed by the various spurious or counterfeit devices presented thereto. the latter being rejected because of-the absence of said specific or particular property or quality therein.

Another object of the invention is to provide an apparatus of the character specified which accepts or rejects metallic coins or tokens depending on the value of the elec I genuine coin or token is presented for test and not obtained when other coins or tokens are presented.

Another object of the invention is to provide an apparatus of the character specified in which one means thereof discriminates in general between metallic and non-metallic coins, tokens, slugs or the like devices present'ed thereto, re ecting the non-metallic de-- nates between the various metallic devices presented thereto, rejecting the devices having a composition differing from that of genuine coins or tokens.

Another object of the invention is to provide an apparatus of the character specified which directly returns the spurious or counterfeit coins, slugs or like devices to the person presenting the same, and which diverts the genuine coins or tokens either to a coin bog; or to a point for operating other mechanism.

Another object of the invention is to provide an apparatus'of the character specified in which an impedance is employed for economically reducing the amount of current utilized when the apparatus is idle, and eliminating the use of switches or cut-outs likely to cause surges of current upon the closing,

of the circuit resulting in faulty operation,

and in which means becoming effective in the presence of the coin, token or like device is employed for reducing the impedance to permit of the flow of current of a strength substantially inversely proportional to the resistances of the devices presented.

Other objects will in part be obvious and in part be pointed out hereinafter.

To the'attainment of the aforesaid objects and ends, my invention consists of the novel features of construction, and in the combination, connection and arrangement of parts and in the steps constitutin hereinafter more fully described pointed out in the claims.

Inthe accompanying drawings:

and then and embodying my invention; I

Fig. 2 is a sectional view thereof-on the line 2-2 of Fig. 1, looking in the direction of the "arrows;

Fig. 3 is an'elevation at one side thereof; Fig. 4 is a' plan thereof said method Figure 1 is a front elevation showing one form of apparatus constructed according to Referring to the drawings the apparatus is shown as mounted upon a frame or support cludes an endless magnetic core 30, prefer- 10 having a front panel 12 and a rear panel 14, and preferably formed as a casing in which certain of the parts are received.

Electromagnets or solenoids 16, 18 and 20 are. secured one above the other to the inner side of the panel 12, the same being provided with the reciprocating magnetic cores or plungers 22, 24 and 26 projecting at the foras the coin passes through the opening 58.

ward ends thereof through the panel 12.

An electrical element 28 resembling a. transformer, and constituting the means for testing the coins, tokens or like devices is secured to the inner side of the panel 12 laterally of the solenoids. This element inably of laminated construction, and a multiturn coil 32 thereon in circuit with a source of alternating current and constituting a choke or impedance. 'A U-shaped member 34 for controlling or reducing the impedance of the coil 32 is also mounted on the core .32 in insulated relation thereto, and the same normally forms an open circuit having a gap 1 I 36 therein. The ends of the member '34 extend through an opening 38 in panel 12 to be exposed at the front thereof .for engagement with the coin or like device to form a closed endless circuit. I

A vertically extending uideway 40 for the coins or tokens is dispose upon the front of the panel 12'over the opening 38, said guideway40 having an entrance opening 42 at the up r end through which the coin or token is inserted and an openin or outlet 44'at the lower end through w ich the coin or.

token, if spurious or counterfeit, is returned to the person inserting the same. A cup 46' for receiving the returned coin or token is secured to the panel 12 below the guideway 40.

Suitable means 48 for diverting the genuine coins or tokens from the guideway 40 are disposed below the transformer 28 upon the anel 12. This means includes a chute member 50 pivoted at 52 within an openin 54 in 1 e-way panel 12 communicating with the i that the 40, the pivot 52 being so locate open upper end 56 of member 50 normally other devices, such as bells or other signalling or indicating devices, or other mechawhich mechanisms the selector apparatus embodying the present invention may be incor orated.

he member 50 is preferabl formed as a magnetic armature controlle as hereinhism to bcontrbinhedfl y said after described, by the electromagnet or solenoid 60 mounted on a bracket 62 secured to the insideof the panel 12. A spring detent 64 enga es the member 50 when the latter is moved y the energized solenoid 60 and retains the member 50111 position with the end 56 thereof extending into the guidewa 40 after the ma et 60 becomes deenergize the member 50 ingreleased from the detent 64-by impact of the coin with the latter The circuit of electromagnet 60 is controlled in turn by the electromagnet 66 of a special relay type having an armature 68 pivoted at 70 below the same, and normally hanging by gravit in disengaged relation to the solenoid 66. he armature 68 has a predetermined weight of a value such as to be attracted only when the current through the relay has a predetermined value. When the armature 68 is lifted the electrical contacts 72 thereon'engage the contacts 74 to close the circuit of with the rimary coil 32 of thetransformer 28 as heremafter described. i The opening or slot 42 through which the solenoid 60; The solenoid 66-is in circuit coin or token is inserted is of substantially.

the size necessar toreceive a coin or token of the deslred while excluding coins or tokens of greater diameter. Coins or tokens smaller thanthose for which the o ning 42 is designed pass through thegui eway 40 without operating the mechanism and are returned intothe receptacle 46. I

' At opposite sides of the slot or opening'42 are spring electrical contacts 76 and 78 in the circuit of the solenoid 16. These contacts are spaced apart' suflicient to permit of the passing therebetween of metallic coins or tokens A of the desired diameter which latter arm 88 having a recessed support 90 at the end thereof. The support 90 carries an electrical contact92, cooperating with a contact 94 upona pivoted member 96, the contacts being-normally pressed toward each other by spring 98. Y

enomination or .diameter,'-

The'support also carries a combined detent and coin retaining member pivoted intermediate its length at 102 and having the inner end thereof 104 adapted to pro.

ject through an opening 106 in the guideway 40 into the path of the coin immediately below the transformer 30, and having the outer end 108 normally pressed downwardly by a spring 110 into engagement with the inner face of the pivoted member 96 to maintain' the contacts in disengaged position. The support 90 is guided by a member 112 secured to the panel 12 and carries a freely slidable in 114 which, when the detent 100 is move outwardly together with the support 90, engages the guiding member 112 and forces the lower end of the member 96 inwardly to permit of the detent 100 engaging the same under the action of spring 110. The contacts 92 and 94 control the circuit of the electromagnet 20 which is actuated to ress a spring arm 116 having an insulat- 1n button 117 thereon against the coin or to en A in engagement with the ends of the secondary 34, and bridgingthe gap 36 therein. For this purpose when the coin or other metallic piece A engages the detent lOO the latter is depressed releasing the member 96 and closing the circuit of magnet 20. When the plunger 26 moves inwardly the same actu- 'ates a cam 118 fixed to a shaft 120 rotating in bearings 122 on the panel 12, the shaft 120 being actuated through an arm 124 having an opening 126 receiving the member 26. The inward movement of the arm 124 is cushioned by means of a spring 128 coiled about the plunger 26 between the nut 130 at the end of shaft 126 and a slidin thereon engaging the outside 0 the arm 124. This arrangement permits of continued movement of the plunger 26 after the cam 118 has fully depressed the spring member 116.

The movement of the plunger 26 also controls the closing of the contacts 134 and 136 in the circuit for the electromagnet 18 for effecting the retraction of the detent 100 which retraction causes the o ening of the contacts 92 and 94' to deenerglze the circuit of magnet 20 to release the arm 116 and permit the coin or token A to travel to its destination.

' In order to allow for a maximum building up of the current through the secondary 34 when the metallic piece A is in position therein, the movement of the contacts 134, .136 towards closing position is retarded by suitable means, such as the dashpot 138. The retarding device or dashpot shown comprises a cylinder 140 secured to the panel 14 and receiving a tubular piston 142 which carries the contact 134. Secured within the piston is a. nut 144 serving as an abutment andha'ving an opening in which the inner end of the lunger 26 is slidably received, the latter bemg retained therein against withdrawal by a washer 132 pin 146. A coil spring 148 is disposed about the plunger 26 between .the abutment 150 secured thereon and the abutment 144. When the electromagnet 20 is deenergized the resiliency of the system controlled thereby returns the parts to inoperative position, the

taken from the usual power line carrying alternating current.

The apparatus depends primarily for operation on characteristics, properties or qualities of genuine or good coins or tokens, such as the silver, copper and nickel alloy coins of the United States and may be employed for testing and assorting coins of the various de-.

nominations. The characteristics of the coin which is relied on is its ohmic resistance. The silver coin, for instance,has a resistance which is lower than that of any other metal from which slugs or spurious coins are usually made, such as from iron, aluminum, lead and the like, and the apparatus herein shown and described as one embodiment of the invention is arranged for operation with silver coins.

. In operation, when the apparatus is not in use and the member 34 is open, the high impedance of the coil 32 and core 30 effectively retards or reduces the flow of alternating current from the main line for the purpose of obtaining economy in the use ofcurrent.

When coins or tokens which are smaller than the opening 42 are inserted the coin slides immediately through the guideway 40 into the return box 46 without actuating the mechanism. Obviously coins too large to pass through the guideway cannot'be used.

When the coin or other device of the proper size is inserted, the device engages the contacts 76 and 78. If such coin or device is of non-metallic or non-conducting material, the same slides through the guideway 40 into the return box 46 without actuating the mechanism.

My apparatus therefore initially rejects coins or devices which are not of the required size or denomination or which are of nonconducting material, thereby preventing by, a simple expedient the use of a large class of slugs or other spurious pieces made of substances such as glass fibre or the like.

If the device inserted is a metallic one of the proper size, the same engages the contacts 76 and 78 closing the circuit of the electromagnet 16 and causing the stop 100 to move into the guideway 40 to prevent the coin or other device A from passing to the return box 46. Asthe coin or device A strikes the detent 'or stop 100, the latter releases the member 96 closing the circuit of the magnet and causing the arm 116 to press the de- Y vice A firmly against the ends of the member 34 closing the circuit thereof and thereby re-. ducing the impedance effect of the coil 32 and allowing a current to flow, which varles in substantially inverse proportion to the resistanccs of the various devices.

With the apparatus shown, when a silver coin of known resistance closes the second: ary gap 36 the increase in current strength or amperage will be sufiicient to magnetically raise the armature 68, and ca e the chute to move into the guideway 40, devices or slugs of higher resistancebeing incapable of operthe predetermined current strength or amperage obtained when a genuine coin or token closes the gap 36, for indicating or makipg known the character of the token or com,

whether the same is genuine or spurious,

and/or for controlling the disposition of the coin, token or likedevice according to the character thereof. The invention is applicable for testing coins, such as silver, which has a resistance lower than all slugs of other metals usually employed, or for testing coins, such as copper or nickel-copper alloys which have resistances of values intermediate the values of the resistances of the slugs of the various metals, some of which may have a lower resistance and some of which may have a higher resistance than the genuine coin or token.

Another characteristic or feature of my invention resides in the impedance means 28 which permits of the use of alternating current, and serves to effectively retard or re-' duce the flow of current when the apparatus is not in, use. the gap 36 the coin is traversed by a relatively small current incapable of causing sparking or unduly heating the coin, and the resulting increase in current through the coil 32 is gradual and accurately corresponds'to the coin resistance.

WVere the c1rcu1t of the testing means controlled by cut-outs or circuit makers or breakers the closing thereof would cause momentary increases in current flow corresponding to that for a genuine coin or token even in the presence of afalse coin, resulting in the inadvertant acceptance of such false coin or de vice by the diverting means 48.

In the present embodiment of my said in-- vention the testing of the tokens'or'coins is lVhen the coin or token closes accomplished first, by testing the size or denomination thereof and discriminating between metallic and non-metallic devices, rejecting all devices except metallic ones of the proper size, and secondly, by testing such spurious coins or devices. Metallic coins or devices presented for test and not satisfying the condition imposed on the apparatus for operation are rejected, thereby renderin unnecessary a number of testing means eac dependent for operation on a different property of the several kinds of slugs or spurious devices which may possibly be submitted for test.

Apparatus embodying'my said invention may be incorporated with other apparatus, if so desired, such as telephone pay boxes, turn-stiles, vending machines, automatic money changes and the like.

I claim:

1. An apparatus of the character described comprising a guideway for a coin, token or like device having an opening .for the insertion of the device and anoutlet for returning the device to the-person inserting the same, means associated with said guideway for testing various electrically conducting devices presented thereto, an electrically actuated member movable into said guideway to retain the device in operative relation to said testing means, said member being normally in inoperative position, a circuit therefor aving contacts contiguous to the engood coms or devices and not possessed by the trance to said guideway-and controlled by the devices inserted, a circuit for saidtesting means, and a memberv movable into said guideway below said testing means and'controlled by said last named circuit to divert the device from said guideway when the reaction thereof on the testing means is that of,

a genuine or good device. 2. An apparatus of the character described comprising a guideway having an entrance ii. opening and a return outlet, means operated.

electrically by conductive coins, tokens orlike devices inserted through said entrance opening to prevent passage of said devices to the return outlet, said means being unresponsive to non-conductive devices to'permit of the return thereof, means for testing the compo' sition of the conductive devices retained in said guideway by said electrically operated means, said testing means including a circuit subjected to the effects of the conductive devices and in the presence of a genuine or good device developing a current flowof predetermined amperage, means for causing the return of the electrically operated means to inoperative position to release the conductive device tested, and means responsive to said current of predetermined'amperage, to the exclusion of currents of other amperages produced by spurious devices, for diverting the genuine devices from the guideway.

3. An apparatus of the character described comprising a guideway for a coin, token orlike device, testing means associated with said guideway, means movable into and out of the path of the device for retaining the device in operative relation to the testing means, and means actuated by contact of said device with said retaining means to press said device against said testing means.

4. An apparatus of the character described comprising a guideway having entrance and discharge openings, means associated with said guideway for testingcoins, tokens or like devices, means operated electrically by the device and movable into said guideway to retain the device in operative relation to said testing means, and means operatedelectrically by said device for pressing the device against said testing means.

5. An apparatus of the character described comprising means for testing coins, tokens or like devices, a guideway thereto, a stop.

r netic means controlled by the engagement of said device with said stop for actuating said pressing means, and means controlled by said last named electromagnetic means for releasing said device.

6. An apparatus of the character described comprising a guideway having a direct passage for the return of coins, tokens or like devices, a circuit associated with said guideway having means for engagement with the devices to vary the current in said circuit substantially in inverse proportion to the resistance of said devices, said circuit being immune to devices of non-conductive material, and means responsive to the current of the amperage obtained upon contact of a genuine coin or token with said engaging means for diverting the coin or token from said guideway.

7. An apparatus of the character described comprising a circuit having an impedance therein, means for controlling the eifect of said impedance including a normally open 'secondary circuit adapted to be closed by a coin, token or like device, whereby to vary the current in the impedance circuit substantially in inverse proportion to the resistance of said devices, and means responsive to a current of predetermined amperage in said circuit for indicating whether the device is genuine or spurious.

ly proportional to the resistance of .the de- Vices closing the circuit of the conductive member, and means responsive only to a current of predetermined amperage for indicating the nature of the devices being tested.

9. An apparatus of the character described comprising a guideway for coins, tokens or like devices, stopping means movable into said guideway, a circuit including a member having a gap facing said guideway, said member when closed by a genuine device causing a current of predetermined amperage in said circuit, electrical means operated by the device inserted for moving said stopping means into said guideway to prevent the passage of the device below said gap, means for pressing said device against said gap, electrical means operated by engagement of the device with said stopping means for actuating said pressing means, said electrical means having a delayed movement, electrical means operated by said last-named electrical means for releasing the device, a chute movable into said guideway for diverting the device if genuine therefrom, and electrical means responsive only to said current of predetermined amperage for actuating said chute.

l0. An apparatus of the character de scribed comprising a guideway open at the upper and lower ends thereof and receiving coins, tokens or like devices, stopping means movable into said guideway and normally withdrawn therefrom, electromagnetic means having a circuit provided with contacts at the upper end of said guideway and controlled by the -device inserted, if the device is conductive, for moving the stopping means into said guideway, a closed magnetic core, a circuit ineluding an impedance coil disposed about said core and adapted to carry alternating current, a U-shaped member about said core constituting an open secondary circuit facing said guideway above said stopping means, said secondary circuit when closed by a genuine device causing a current of predetermined amperage in said first named circuit, electrical means operated by said device for pressing the device against said member, means operating automatically for releasing said pressing means and said stopping means and having a delayed action, a chute movable into said guideway for diverting the device, electromagnetic means for controlling said chute,

and electrically operated means responsive only to said current of predetermined amperage for controlling the circuit of said lastnamed electromagnetic means.

11. An apparatus of the character described comprising electrical means for testing coins, tokens or like devices, means actuated thereby for controlling the disposition of the device, stop means for retaining the device in operative relation to the testing means,

and device controlled means for moving the stop means to and from operative position.

12. An apparatus of the character described comprising electrical means for testing coins, tokens or like devices, means actuated thereby for controlling the disposition of the device, stop means for retainingthe devlce in operative relation to the testing means,

said stop means including a circuit controlling member, electrical means energized by insertion of the'device for moving said stop means to operative position, and electrical means controlled by engagement of the device w th said circuit controlling member. for returning the stop means to inoperative position.

13. An apparatus of the character described comprising means for testing the com-.

position of coins, tokens or. like devices including a circuit subject to the effects of conductive devices and in the presence of a good device developing acurrent of predetermined amperage, means responsive to said current of predetermined amperage, to the exclusion of currents of other amperages produced by spurious devices, for diverting the genuine devices, stop means for retaining the device In operative relation to the testing means,

- means operated by the device inserted or moving said stop means to operative position, and means for returning the stop means to inoperative position.

14, An apparatus of the character described comprising an impedance circuit normally restricting the flow of current therein, means adapted to be engaged'by coins, tokens or like devices for reducing the impedance and developing a current flow in the circuit varying With-the resistances of the devices,

and means selectively responsive to the current developed in the presence of-a genuine device for controlling the disposition of the devices.

15. An apparatus of the character -de scribed comprising an impedance circuit nor- -mally restricting the flow of current therein,

means adapted to be engaged by coins, tokens or like devices for reducing the impedance and developing a current flow in said circuit varying with .the resistances of the devices,

means for pressing the device into engagement with said impedance reducing means,

' and means selectively responsive to'the current developed in the presence of the genuine device for controlling the disposition of the devices.

16. An. apparatus of the character described comprisin a circuit having means for engaging coins, to ens or like devices to vary the current therein in accordance with the resistances of the devices, said circuit including electromagnetic means .controlling the responsive to the devices of least resistance and immune to devices of greater resistance.

' 17. An apparatus of the character described comprising an impedance circuit normally restricting the flow of current therein, means adapted to be engaged by coins, tokens .70 disposition of the devices and'adjusted to be or like devices for reducing the impedance and developing a current flow in the circuit varying in inverse relation to the resistances of the devices, means for resiliently pressing the device into engagement with the impedance reducing means, means for controlling the engagement and disengagement of the pressing means and device, and means responsive to the current developed in the tion, means for pressing the device against the contact, electrical means for actuating the pressing means and returning said stop means to inoperative posltion, and means for retarding the releasing movement of the stop and pressing means.

19. An apparatus of the character described comprising electrical means for testing coins, tokens or like devices, means actuated thereby for controllingthe disposition of the devices, stop means moved by the device into operative position to retain the device in position relative to the testing means,

means for pressing the device against the testing means, and common means for actuating said pressing means and said stop means to return the latter to inoperative position. I

20. An apparatus of the character described comprising electrical means. for testmg various electrically conducting coins, tokens or like devices'presented thereto, a

movable chute associated with said testing means and controlled thereby for controlling the disposition of the device, a normally inoperative electrically actuated member for retaining the device in operative position relative to the testing means, and "a circuit therefor havin contacts adjacent to the entrance for the evice to insure closing of the circuit by insertion of the device across said contacts.

21. An apparatus of the character described comprising a closed magnetic core, a circuit-including an impedance coil dis-, posed about said core, a member on said core having a gap and constituting, an open secondary circuit adapted to be closed by a coin,

token or like device to vary the current in said first named circuit, said secondary circuit when closed by a genuine device producing in said first named circuit a current of predetermined value, guiding means actuated in response to said circuit of predetermined value for controlling the destination of the device, stop means actuated by the insertion of the device for retaining said device in position relative to the gap of said secondary member, means for pressing the device against said secondary member, and means for controlling said pressing means and the movement of said stop means to inoperative position.

22. An apparatus of. the character de-. scribed comprising a circuit having an electromagnetic coil therein, means for presenting coins, tokens or like devices of various compositions to said circuit to cause current through said coil inversely proportional to the resistances of the various devices, and means controlled by the magnetic effect of said coil for controlling the disposition of the device, said last named means being made responsive to the magnetic effect of the particular value developed upon presentation of the genuine device to the circuit Without being responsive to the magnetic effects developed upon presentation of devices of other resistances to said circuit.

An apparatus of the character described comprising a circuit having an electromagnetic coil therein, means for presenting coins, tokens or like devices of various compositions to said circuit to cause current through said coil inversely proportional to the resistance of the various devices, and means controlled by the magnetic effect of said coil for controlling the disposition of the device, said last named means including an armature adjusted to be responsive to the 'magnetic effect of the particular value developed upon presentation of the genuine device to the circuit and to be immune to magnetic effects developed upon presentation of devices of greater resistances to said circuit.

24. An apparatus of the character described comprising an impedance circuit including electromagnetic means and adapted to be traversed by a fluctuating current, means for presenting coins, tokens or like devices of various compositions to said cir-- cuit to reduce the impedance and cause cur rent through said electromagnetic means inversely proportional to the resistances of the various devices, and means controlled by the magnetic effect of said electromagnetic n ans for controlling the disposition "of'thc dey -e, said last named means being made m to the magnetic effect of the particular value developed upon pres'entation'of thegenu'ihc, device to the circuit without being responsive ter of thedevice presented.

26. The hereindescribed method of distinguishing between genuine and spurious coins, tokens or like devices which consists in presenting the device to a circuit andutilizing the device to vary the current as an inverse function of the electrical resistance of the device, and translating the current of the amperage obtained in the presence of a given device to the exclusion of current of the amperages obtained in the presence of other devices into mechanlcal movement for indicatlng the character of the device presented.

27. The hereindescribed method of distinv guishing between genuine and spurious coins, tokens or like devices which consists in ,presenting the devices to a circuit and-utilizing the devices to vary the current in inverse relation to the ele'ctricalresistance of the devices, and translating the current of the amperage obtained in the presence of a genuine device of silver composition to the exclusion of current of other amperages obtained in the presence of spurious devices into sensible form for indicating the presence of the genuine device.

- guishing between genuine and spurious coins,

tokens or like devices which consists in presenting the. devices to a circuit and utilizing the devices to vary the current in inverse relation to the electrical resistance of the deresistances to vices, and translating current of the amperage obtained in the presence of a genuine device to the exclusion of current of the amperag'es obtained in the presence of other devices into a sensible form for indicating the presence of said genuine device.

30. The hereinde'scribed method of distinguishing between genuine and spurious coins, tokens or like devices which consists in presenting the device to a circuit and utilizing the device to vary the current as a function of the electrical resistance of the device, and mechanically controlling the disposition of the device by the magneticefiect of the current developed in the presence of the device 7 of least resistance while preventing such mechanical control by magnetic effects of lesser intensityproduced in the presence of other devices.

o 31. The hereindescribedmethod of distinguishing between genuine and spurious coins, tokens or like devices which consists in presenting the device to a circuit and utilizing the device to vary the current asan inverse function of the electrical resistance of the device, and translating said current, only when of the predetermined amperage obtained in the presence of a good device, into sensible form for indicating the character of the device presented. a

. 32. The hereindescribed method ofdistinguishing between genuine and spurious-coins, tokens or like devices which consists in presenting said device to an impedance circuit 85 and utilizing the conductivity of the device for reducing the impedance and causing a flow of current which varies as a function of Y the resistance of the device presented for test, and translating the current of certain of the amperages obtained into sensible *form for making known whether the device tested is genuine or spurious.

In testimony whereof, I have signed my name hereto. Y FAIRFIELD W. HOBAN.

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