License testing device for vending machine, has optical sensor for determining rotating speed of grid wheel, and character recognition device for scanning license with frequency, based on rotating speed of grid wheel

摘要

The device has a speed control module (3) comprising a gear set (31). An accelerating gear (32) is connected with the gear set. An optical grid device (33) is rotatably shifted by the accelerating gear. An optical sensor (333) determines rotating speed of an optical grid wheel (332). A character recognition device (4) scans a license, which is included in a license insertion port, with a frequency based on the rotating speed of the optical grid wheel. The gear set comprises an inner gear wheel and a friction strip.