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 coin sorting device is designed to inhibit tampering with a coin operated machine by means of a wire, metal tape or the like, and to further prevent non-acceptable coins from being accepted by the coin-operated machine.