Patent ID: 8708129
Filing Date: 2014-04-29
Classification: G07D

Abstract:
1. A dust prevention system for a coin sensor for detecting a size of individual ones of a plurality of coins being moved within a coin handling machine, the system comprising: a stationary and substantially horizontal coin track; a coin moving element positioned for pressing down on outside portions of the coins as the coins move along the coin track; an upper optical element and a lower optical element that are spaced apart for illuminating a portion of a coin as a plurality of coins move along the substantially horizontal coin track in single file, the coin track having an inside edge; wherein the coin track is stationary and is narrower than the coins passing over the coin track, the coin track having a width such that when coins pass along the coin track, the coins have portions that are cantilevered over the inside edge of the coin track by the pressing down on the coins provided by the coin moving element to enable illumination and detection of portions of the coins extending beyond the inside edge of the coin track; wherein the lower optical element has a transparent cover; and wherein the inside edge of the coin track is spaced above the transparent cover for the lower optical element and is spaced below the upper optical element to prevent accumulation of dust on the upper optical element and on the transparent cover for the lower optical element.