| 摘要 |
PURPOSE:To provide a function as an encoder, to reduce size, to cause a device to form compact structure, and to reduce weight by locating a part to be detected at least in one spot on the timing belt or the pulley of a rotation transmitting means and detecting the part to be detected by means of a detecting means. CONSTITUTION:A timing belt 15 through which running of a motor 11 is transmitted to a rotary shaft 12 can transmit rotation without incurring of a loss, such as a slip, and rotation of a rotary shaft 12 accurately responds to the feed of the timing belt 15. In which case, a part to be detected is formed such that a number of microthrough-holes 17, 17... are formed at equal intervals in the timing belt 15 run around a pulley 13 of the motor 11 and a pulley 14 of the rotary shaft 12 and therebetween. By locating a transmission type photo sensor, i.e., a photo coupler 18, to detect the microthrough-hole 17 being the part to be detected, a detecting mechanism in the rotary angle position of an ultrasonic transmitter receiver is formed. |
