Coin discriminating apparatus

Claim 2

Coin discriminating apparatus comprising a bridge circuit including an electromagnetic detection coil, a reference element and a pair of proportionality arm elements; a bandpass filter connected to the output of said bridge circuit; an amplifier for amplifying the output of said bandpass filter; a discriminator connected to the output of said amplifier; and a feedback loop for positively feeding back the output of said amplifier to said bridge circuit to measure the attenuation characteristics of coins subjected to the action of the electromagnetic detection coil, the feed back loop being constructed such that upon a given coin to be discriminated favorably being subjected to the magnetic field created by said electromagnetic detection coil the feedback loop is maintained in one operating condition, and upon coins to be discriminated against being subjected to the electromagnetic coil, the feedback loop converts to a different operating condition, said discriminator being responsive to the operating condition of the feed back loop.

Claim 3

The coin discriminating apparatus according to claim 1 wherein said bridge circuit comprises an electromagnetic detection coil for discriminating coins, a reference element connected to one end of said electromagnetic detection coil, said reference element manifesting an impedaNce equivalent to the impedance manifested by said electromagnetic detection coil when a given coin to be discriminated favorably is brought into the magnetic field created by said electromagnetic detection coil, a first proportionality arm element connected to the other end of said electromagnetic detection coil and a second proportionality arm element connected between the other end of said reference element and the other end of said first proportionality arm element, said bridge circuit being constructed to assume a balanced condition only when a given coin to be discriminated favorably is brought to said electromagnetic detection coil to thereby maintain the feedback loop in a non-oscillatory condition, and said bridge circuit assumes an unbalanced condition upon a coin to be discriminated against being brought to said electromagnetic detection coil whereby the feed back loop is maintained in an oscillatory condition.

Claim 4

The coin discriminating apparatus according to claim 2 wherein said discriminator comprises means for smoothing an AC signal from said amplifier for producing a DC voltage, means responsive to said DC voltage for determining a permissible balanced voltage level which is used to detect the balanced condition of said bridge circuit, and signal generating means responsive to the operation of said D.C. voltage responsive means for determining the permissible balanced voltage level for generating a coin discriminating signal.

Claim 5

The coin discriminating apparatus according to claim 2 wherein said reference element comprises a coil having the same rating as said electromagnetic detection coil and a reference metal piece having the same characteristic as said given coin to be discriminated favorably, said reference metal piece being positioned in the magnetic field of the coil of said reference element.

Claim 6

The coin discriminating apparatus according to claim 3 wherein said means for determining the permissible balanced voltage comprises a Zener diode.

Claim 7

The coin discriminating apparatus according to claim 4 wherein said reference element comprises a coil divided into two sections and having the same capacity as said electromagnetic detection coil, a pair of spaced apart magnetic cores, said two sections being wound upon said cores respectively to produce magnetic fields in the same direction, a reference metal piece manifesting the same impedance as the center value of the impedance distribution manifested by said electromagnetic detection coil when a given coin to be discriminated favorably is brought thereto, said reference metal piece being mounted close to the flux generating surface of one of said cores, a base for supporting one of said cores and a slide plate slidably mounted on said base and supporting the other of said cores.

Claim 8

Coin discriminating apparatus comprising a bridge circuit including an electromagnetic detection coil included in the first arm, of said bridge circuit, proportionality arm elements respectively included in the second and third arms, and a plurality of reference elements adapted to be selectively connected in the fourth arm of said bridge circuit; a bandpass filter connected to the output of said bridge circuit; an amplifier for amplifying the output of said bandpass filter; a discriminator connected to the output of said amplifier; a feed back loop for positively feeding back the output of said amplifier to said bridge circuit; and a change over device for selectively connecting one of said reference elements in said fourth arm when said discriminator detects the unbalanced condition of said bridge circuit upon a coin being brought to said electromagnetic detection coil.

Claim 9

Coin discriminating apparatus comprising a bridge circuit including an electromagnetic detection coil included in the first arm, of said bridge circuit, proportionality arm elements respectively included in the second and third arms, and a plurality of reference elements adapted to be selectively connected in the fourth arm of said bridge circuit; a bandpass filter connected to the output of said bridge circuit; an amplifier for amplifying the output of said bandpass filter; a discriminator connected to the output of said amplifier; a feed back loop for positively feeding back the output of said amplifier to said bridge circuit; and a change over device for selectively connecting one of said reference elements in said fourth arm when said discriminator detects the unbalanced condition of said bridge circuit upon a coin being brought to said electromagnetic detection coil.

Claim 10

The coin discriminating apparatus according to claim 7 wherein each one of said reference elements manifests an impedance equivalent to the impedance manifested by said electromagnetic detection coil upon a predetermined coin to be discriminated favorably being inserted in the magnetic field produced by said electromagnetic detection cOil.

Claim 11

The coin discriminating apparatus according to claim 7 which further includes means for producing discriminating signals indicating whether the inserted coins correspond to predetermined types or not.

Claim 12

The coin discriminating apparatus according to claim 8 wherein each one of said reference elements comprises a coil having the same rating as said electromagnetic detection coil and a reference metal piece cooperating with said first mentioned coil and having the same characteristic as a particular coin to be discriminated favorably thereby.

Claim 13

The coin discriminating apparatus according to claim 10 wherein each one of said reference elements comprises a coil divided into two sections, a pair of spaced apart magnetic cores, said coil sections being wound upon said magnetic cores respectively to produce magnetic flux in the same direction, a reference metal piece manifesting the same impedance as the center value of the impedance distribution manifested by the coins of a predetermined type to be discriminated favorably by said one reference element, said reference metal piece being mounted on the flux generating surface of one of said cores and a base for supporting one of said cores, a slide plate slidably mounted on said base for supporting the other of said cores.

Claim 14

A coin discriminating apparatus comprising an electromagnetic detection coil divided into two sections, each section being supported within magnetically permeable, insulating housings secured on respective sides of a coin receptacle, a pair of spaced apart magnetic cores each mounted in a respective one of the housings with said two sections of said coil being wound upon said cores respectively to produce magnetic fields in the same direction such that upon a coin being deposited in the coin receptable, it is disposed in the flux path between the two cores and causes a characteristic impedance value to be manifested by said electromagnetic detection coil.

Claim 15

A coin discriminating apparatus comprising an electromagnetic detection coil divided into two sections, each section being supported within magnetically permeable, insulating housings secured on respective sides of a coin receptacle, a pair of spaced apart magnetic cores each mounted in a respective one of the housings with said two sections of said coil being wound upon said cores respectively to produce magnetic fields in the same direction such that upon a coin being deposited in the coin receptable, it is disposed in the flux path between the two cores and causes a characteristic impedance value to be manifested by said electromagnetic detection coil.

Claim 16

A coin discriminating apparatus comprising a reference element for inclusion in a measuring bridge with an electromagnetic detection coil, said reference element including a coil divided into two sections, a pair of spaced apart magnetic cores, said coil sections being wound upon said magnetic cores respectively to produce magnetic flux in the same direction, a reference metal piece manifesting the same impedance as the center value of the impedance distribution manifested by the electromagnetic detection coil in the presence of coins of a predetermined type to be discriminated favorably by said reference element, said reference metal piece being mounted on the flux generating surface of one of said cores, a base for supporting one of said cores and a slide plate slidably mounted on said base for supporting the other of said cores.

Claim 17

A coin discriminating apparatus comprising a reference element for inclusion in a measuring bridge with an electromagnetic detection coil, said reference element including a coil divided into two sections, a pair of spaced apart magnetic cores, said coil sections being wound upon said magnetic cores respectively to produce magnetic flux in the same direction, a reference metal piece manifesting the same impedance as the center value of the impedance distribution manifested by the electromagnetic detection coil in the presence of coins of a predetermined type to be discriminated favorably by said reference element, said reference metal piece being mounted on the flux generating surface of one of said cores, a base for supporting one of said cores and a slide plate slidably mounted on said base for supporting the other of said cores.