DEVICE FOR DETECTING OPERATING POSITION OF TAPE RECORDER

PURPOSE:To obtain a miniaturized operating position detecting device which produces less noises and has a high reliability, by providing a specular surface part and a rough surface part to a position detecting gear and controlling a motor which drives the position detecting gear by detecting said surface parts by a photoelectron. CONSTITUTION:A cam driving gear 21 is fixed to the revolving shaft of a gear driving motor 27. Transmission gears 22 and 23 are meshed with each other and, in addition to the above, the transmission gear 22 is meshed with the cam driving gear 21. A position detecting gear 24 is supported freely rotatably by a base body 1 and is meshed with the transmission gear 23. A specular surface part 24b provided to the opposite surface where a cum part 24a of the position detecting gear 24 is provided, is composed of a rough surface part 24c and reflecting parts which alternate with the rough surface part when the gear 24 is rotated. When the position detecting gear 24 is rotated, reflection and irregular reflection are caused against a photoelectron 26 by the specular surface and rough surface parts 24b and 24c and a pulse is generated. A control circuit is operated by the pulse.