To prevent detecting as passage of true coins, due to the intrusion of a false signal body.

A coin passage 11 is provided with a sensor 40 for optically detecting the thrown-in and passing coin 54 in a detecting optical path 201 with a non-contact distance X, and a guard part 202 for guarding the sensor 40 from the false signal body 200, outside the detecting optical path 201 between the coin passage 11 and a sensor surface 40a so that the false signal body 200, intruding into the coin passage 11 will not reach the predetermined position in front of the sensor surface 40a and to give the sensor 40 a signal that replaces the passing coin 54.