Method and apparatus for use in an inductive sensor coin selector

Claim 3

The method of claim 1 wherein the value representative of the function is the arithmetic difference between the first and second values.

Claim 6

The method of claim 3 wherein the value representative of the function is the arithmetic diFference between the first and second values.

Claim 7

The method of claim 4 wherein the quality representative of the degree of interaction is the frequency of the magnetic field.

Claim 8

The method of claim 5 wherein the first and second values of the quality are each produced by counting the pulses of the field frequency, further including the step of storing one of said values for use in producing the second signal.

Claim 9

The method of claim 6 wherein values representative of the function for the coin are produced throughout the period during which the coin is subjected to the field further including the step of determining whether the coin is acceptable only if the largest of said values is within predetermined limits for acceptable coins of a given denomination.

Claim 10

The method of claim 7 wherein the value representative of the function is the arithmetic difference between the first and second values.

Claim 11

The method of claim 3 wherein the quality representative of the degree of interaction is the frequency of the magnetic field.

Claim 12

The method of claim 9 wherein the first and second values of the quality are each produced by counting the pulses of the field frequency, further including the step of storing one of said values for use in producing the second signal.

Claim 13

The method of claim 10 wherein values representative of the function for the coin are produced throughout the period during which the coin is subjected to the field further including the step of determining whether the coin is acceptable only if the largest of said values is within predetermined limits for acceptable coins of a given denomination.

Claim 14

The method of claim 11 wherein the value representative of the function is the arithmetic difference between the first and second values.

Claim 15

The method of claim 3 wherein values representative of the function for the coin are produced throughout the period during which the coin is subjected to the field further including the step of determining whether the coin is acceptable only if the largest of said values is within predetermined limits for acceptable coins of a given denomination.

Claim 16

Apparatus for examining coins with respect to authenticity including inductor means for subjecting a coin to an alternating magnetic field, means for producing a first signal having a quality representative of the degree of interaction of the coin with the field, means for storing a first value of the quality of the first signal determined when no coin is in the presence of the field, function generator means connected to receive the first value and a second value of the first signal determined when the coin is in the presence of the field to produce a function of the first and second values, and comparator means connected to receive the output of the function generator means for comparing a value representative of the function of the coin with a value representative of the function of an acceptable coin.

Claim 17

Apparatus for examining coins with respect to authenticity including inductor means for subjecting a coin to an alternating magnetic field, means for producing a first signal having a quality representative of the degree of interaction of the coin with the field, means for storing a first value of the quality of the first signal determined when no coin is in the presence of the field, function generator means connected to receive the first value and a second value of the first signal determined when the coin is in the presence of the field to produce a function of the first and second values, and comparator means connected to receive the output of the function generator means for comparing a value representative of the function of the coin with a value representative of the function of an acceptable coin.

Claim 18

The apparatus of claim 14 further including a coin passageway having non-conductive sidewalls between which coins to be examined pass along a predetermined path and a conductive target, wherein the inductor is located on one side of the path and the target is located on the other side of the path opposite the inductor.

Claim 19

The apparatus of claim 15 wherein the first signal producing means is an oscillator having the inductor as a frequency determining component.

Claim 20

The apparatus of claim 15 wherein the quality of the degree of interaction of the coin with the field is the frequency of the first signal.

Claim 21

The apparatus of claim 15 wherein the function generator means produces the arithmetic difference between the first and second values.

Claim 22

The apparatus of claim 14 further including a coin track along which coins to be examined are conducted through the field, a first non-conductive sidewall on one side of the track to which the inductor is mounted, a second non-conductive sidewall on the other side of the track to which a conductive target is mounted opposite the inductor, the sidewalls being relatively moveable.

Claim 23

The apparatus of claim 19 wherein the first signal producing means is an oscillator having the inductor as a frequency determining component.

Claim 24

The apparatus of claim 19 wherein the quality of the degree of interaction of the coin with the field is the frequency of the first signal.

Claim 25

The apparatus of claim 19 wherein the function generator means produces the arithmetic difference between the first and second values.

Claim 26

The apparatus of claim 14 wherein the first signal producing means is an oscillator having the inductor as a frequency determining component.

Claim 27

The apparatus of claim 14 wherein the quality of the degree of interaction of the coin with the field is the frequency of the first signal.

Claim 28

The apparatus of claim 14 wherein the function generator means produces the arithmetic difference between the first and second values.

Claim 29

Apparatus for examining coins with respect to authenticity including a coin passageway along which a coin to be examined will pass on a predetermined path, an oscillator including an inductor within its frequency determining circuit which produces a first signal having a frequency representative of the degree of interaction of the magnetic field of the inductor with coins within the field, means for preserving a first value of the frequency of the first signal determined when no coin is in the field, function generator means for producing second signal having a value representative of the difference between the first value of the first signal and a second value of the frequency of the first signal determined when the coin is in the field, and a comparator arranged to compare the value of the second signal representative of the difference for the coin with a value representative of the difference for an acceptable coin.

Claim 30

Apparatus for examining coins with respect to authenticity including a coin passageway along which a coin to be examined will pass on a predetermined path, an oscillator including an inductor within its frequency determining circuit which produces a first signal having a frequency representative of the degree of interaction of the magnetic field of the inductor with coins within the field, means for preserving a first value of the frequency of the first signal determined when no coin is in the field, function generator means for producing second signal having a value representative of the difference between the first value of the first signal and a second value of the frequency of the first signal determined when the coin is in the field, and a comparator arranged to compare the value of the second signal representative of the difference for the coin with a value representative of the difference for an acceptable coin.

Claim 31

The apparatus of claim 26 further including a conductive target located on the opposite side of the path from the inductor.