Anti-fraud device for vending machine coin unit - uses three spring biased sliding plates mutually blocking one another on encountering invalid coin

摘要

The device prevents introduction of other than valid coins into a vending machine and comprises a blocking system with three sliding elements. Two of these slide in opposite directions and are subjected to a spring bias while the third slides perp. to them. The three elements are arranged so that any one of them can be blocked by the other two. The blocking of the third element which slides perp. to the other two is effected by a narrow projection extending from each of the two facing edges of the latter two elements. Pref. each element has a spring-biased pivoted tongue acted on by an inserted valid coin, to release the blocking element.