Abstract: A method and apparatus for identifying a coin in free fall employs a coin sensor that has a pair of drive coils for generating a horizontally elongated magnetic field across a free-fall path of the coin. The drive coils are driven by a square wave, and ringing waveforms induced in a pair of sensor coils disposed on the two sides of the free-fall path are measured when the coin passes through the magnetic field. A digitized signature is derived from the measured ringing waveforms and compared to a set of pre-stored reference signatures to find a match. A diverter mechanism directs the coin to an accept path when a match is found and to a reject path when a match is not found.

Abstract: An apparatus for detecting fraud in a coin detector is disclosed. The apparatus is provided with a coin validating device. A coin sensing apparatus, located downstream of the coin validating device and preferably including a plurality of optic emitter-detector pairs arranged to detect the passage of the coin, is also provided. The coin sensing apparatus is adapted to provide improved resistance to miscounting of coins and to traditional gimmicks used to cheat coin operated devices such as tilting the coin detector.

Abstract: A coin detection and identifying apparatus and method, utilizes three closely aligned electric coils. The center coil is actively driven by an alternating current to generate a magnetic field that surrounds the center coil. The two outer coils are symmetrically disposed within the magnetic field generated by the center coil, and voltages are induced across the terminals of the outer coils which are indicative of the relative field strengths of the magnetic fields within the outer coils. A sample coin and test coin are interposed between the center coil and each of the outer coils, the coins operative to attenuate the surrounding magnetic fields. A controller compares the voltages across the terminals of the two outer coils to effectively compare the likeness of the sample and test coins. A coin sensing apparatus, located downstream of the coils, provides a plurality of optic emitter-detector pairs to detect the valid passage of a coin.

Abstract: A discriminator for coins and tokens monitors the extent to which an alternating electromagnetic field is coupled through a deposited coin and a reference coin, as the deposited coin passes along a feed path. A first electromagnetic field is incident on a reference coin along an axis normal to the reference coin and displaced from a midpoint of the reference coin. As the deposited coin moves through a second electromagnetic field traversing the feed path, the deposited coin passes two positions at which the second electromagnetic field is aligned to the deposited coin to a same degree as the first electromagnetic field is aligned to the reference coin. The electromagnetic fields preferably are provided by two series connected coils in a stack, and the fields passing through the coins are added at opposite polarity by a receiver coil placed between the series connected coils (and also between the sample coin and the deposited coin).

Abstract: A coil used in electronic coin testers for testing a coin for the purpose of accepting a valid coin or rejecting a counterfeit coin in a coin-operated vending machine, game, telephone or the like is disclosed. A coin slot is provided having two opposing longitudinal walls spaced to accommodate a coin therebetween of either the sample coin type or the test coin type. Within each longitudinal wall a planar looped coil is provided that, upon inducement of an electric current, generates lines of magnetic flux which are normal to the opposing surfaces of the longitudinal walls throughout the length of the longitudinal walls.

Abstract: In the part of the passageway leading out of a coin testing apparatus is an L-shaped member comprising an upright leg and a generally horizontal foot which lies in a plane coincident with the thickness (narrow dimension) of the passageway. The leg is suspended for pivotal movement about an axis normal to that plane and the foot projects into the passageway to be contacted by a selected coin descending through the passageway, which coin would thereby cause the member to pivot with the coin thereby being permitted to continue to descend. The foot is sufficiently close above the actuating arm of an electrical switch that, if a tethered coin descends below the member sufficiently far to move the arm to switch actuating position, the foot will then have pivoted back into the passageway and will prevent the coin from being raised to a level at which the switch arm is returned to switch-deactuated position.