CONTROL MEANS REACTIVE UPON METAL OR ALLOY

摘要

A control device particularly for detecting the insertion of an incorrect coin or a counterfeit coin into a coin-actuated or coin-freed machine. The coin engages between a heated electrode (4) and an unheated conductor (5) and so the coin together with the electrode (4) and the conductor (5) forms "hot" and "cold" junctions. This generates an e.m.f. by a thermo-couple or the Seebeck effect. When the coin is made of the correct metal or quantity of metal the e.m.f. generated is sufficient to actuate a relay (9) to release the coin to actuate the machine or free it for actuation. Where the e.m.f. is insufficient the machine will remain inoperable. In that case the coin will be released after a predetermined time without operation of the machine.