Abstract: A coin validator is provided with at least two reference positions (U, D) for determining a diameter related characteristic of a coin being validated. In order to reduce the running to the testing station, the timing of a trailing point of the coin passing a first reference position (U) is used to determine the diameter related characteristic. Embodiments using optical inductive and piezo-electric sensors associated with the reference positions are disclosed. An inductive sensor for a coin validator comprises an elongate coil, which, when in use, is arranged such that the magnetic field is substantially constant across the width of the passageway. The use of coils of this type have the advantage of wrap around coils but enable the coin passageway to be shallower and be opened. A coin validator is described wherein the backwall of a coin passageway is movable to and fro so that the depth of the coin passageway can be adjusted.

Abstract: A coin validator is operable in a set up mode prior to normal operation, in which initial window data (W) stored in its memory, is compared with data from a known true coin, and the initial window is progressively dragged and shrunk depending on the outcome of the comparison, to produce an operating window (W′), narrower than the initial window, which can be used during normal operation of the validator, for comparison with coin data (x) from coins under test, in order to determine coin acceptability. The initial window (W) can be the same for all validators of the same design, and the dragging and shrinking configures the operating window (W′) to the validators individually, to take account of manufacturing tolerances.

Abstract: A coin validator with an improved coin processing rate, performs primary validation testing on coins at a primary validation station as successive coins roll down a coin rundown path. Unacceptable coins pass to a coin reject path but coins found acceptable by the primary validation testing are deflected by a solenoid operated gate to a coin accept path. The acceptable coins pass a further sensor coil. Auxiliary coin testing is carried out by a microprocessor by analyzing the time taken for the coin to reach and move away form the further sensor. The microprocessor performs undertimer and overtimer routines FIGS. 3A, B and if the coin arrives within the under and overtimer ranges t.sub.1, t.sub.2, the coin is accepted. When the coin throughput rate is increased, the undertimer is switched off in order to permit the coin throughput rate for valid coins to be increased, without loss of security.

Abstract: A coin validator is provided with at least two reference positions (U, D) for determining a diameter related characteristic of a coin being validated. In order to reduce the running to the testing station, the timing of a trailing point of the coin passing a first reference position (U) is used to determine the diameter related characteristic. Embodiments using optical inductive and piezo-electric sensors associated with the reference positions are disclosed. An inductive sensor for a coin validator comprises an elongate coil, which, when in use, is arranged such that the magnetic field is substantially constant across the width of the passageway. The use of coils of this type have the advantage of wrap around coils but enable the coin passageway to be shallower and be opened. A coin validator is described wherein the backwall of a coin passageway is movable to and fro so that the depth of the coin passageway can be adjusted.

Abstract: In a coin sensing station, coins pass edgewise along a passageway through a transparent block and interrupt three optical sensing beams that transverse the passageway at spaced locations. The beams are produced by light emitting diodes which direct light into the block where it is directed by reflection from inclined surfaces integrally molded into the block. By use of a beam splitting means, it is possible to direct the first and second sensing beams from a single source beam, across the passageway at different, spaced apart locations.

Abstract: A coin sensor, such as a post acceptance sensor for a coin validator, at a coin sensing station on a coin path having a sidewall, includes optical source and detector pairs that detect the presence of the coin by reflection of source radiation to the detector by the coin's surface. In order to improve sensitivity the side wall has an angled surface configuration which inhibits reflection of radiation from each source to the detectors in the absence of a coin.