GB439679A - Improvements in or relating to methods and means for sorting or testing coins and other metallic objects - Google Patents

Abstract

439,679. Testing coins. DOWNES, R. N., 8, St. Mary's Road, East Molesey, Surrey, and SPITTLE, D. G., Elmstead, High Road, Chigwell, Essex. May 29, 1934, No. 15977. [Class 27] [See also Groups II and XXXVI] In means for sorting or testing non - magnetic metallic objects in the form of coins or tokens, the coin or token to be tested, whilst supported upon a movable carrier, is subjected to a magnetic field produced by alternating or interrupted electric current under such conditions that the resulting force of repulsion, arising from the induced eddy currents in the coin or token, is compared with another force corresponding with that set up by a pre-selected standard coin or token subject to the same conditions, and the results of such comparison are observed or utilized from the resultant movement or lack of movement of the carrier. In the construction of testing apparatus shown in Fig. 1, a standard coin and a coin to be tested are placed respectively on arms 9 and 10 of a carrier plate 11 pivoted about a vertical axis, the arms 9, 10 and their coins lying in inclined air-gaps between the pole faces of an electromagnet 1, excited by alternating current, and a bridge-piece 4. Any inequality in size or material between the coins is indicated by a movement of the carrier. The bridge-piece 4 may be pivotally mounted to facilitate introduction of the coins, and may be adapted to close the circuit of the electromagnet when turned into operative position. Fig. 6 shows a construction of sorting apparatus in which two electromagnets 41, 43 are carried by a frame 47 adapted to be rotated on trunnions 48, the two air-gaps between adjacent poles 40, 42 of the electromagnets receiving the two arms of the pivoted carrier 45. Normally the frame 47 is situated so that the carrier is inclined to the horizontal. A coin to be sorted passes down a shoot, e.g. of a coin-freed machine, and is received by one arm of the carrier, a standard coin being situated in the other arm. During testing of the coin, the carrier 47 is rotated through gearing 50, 51 to bring the arm containing the coin level with two or more discharge shoots, the coin passing off the carrier, and down one or other of the shoots, according to the result of the test and angular position of the carrier about its pivots. Means may be provided to hold the carrier normally in displaced position so that movement of the carrier to the normal position occurs with a correct coin.