| 摘要 |
<p>A coin discriminating apparatus comprises a coil 1 and 2 on opposite sides of a path for coins, coil 1 being connected to a signal generator so as to give repetitive abrupt flux changes and means 4 being provided for short circuiting coil 2 but removing the short circuit a predetermined time delay after each flux change. A means 5 is responsive to the amplitude of a voltage pulse which is produced across coil 2 in response to each removal of the short circuit to discriminate between coins.This apparatus may form the second test of a two-test coin discriminating apparatus, wherein the first test measures a phase displacement caused by the coin passing between another pair of coils and this measurement is used to set the time delay to one of selected values, according to the expected coin, so that the voltage pulse will be of a constant amplitude of valid coins. <IMAGE></p> |
