| 摘要 |
PURPOSE:To simplify extremely an electric circuit for executing an operation of an arm by providing plural light emitting diodes in one straight line on a fitting base, and detecting a position of the arm by a phototransistor provided on a truck of the arm. CONSTITUTION:Plural light emitting diodes 2a-2y corresponding to a rest position, a lead-in position, a lead-out position, etc. of every record size are provided in one straight line on a fitting base 1. Also, one phototransistor 4 is fitted to the lower surface of a truck 3 moving together with a linear tracking arm 5. By this constitution, the light emitting diodes 2a-2y are made to emit light in accordance with the record size, it is detected by the transistor 4, and detection of a necessary position is executed. Therefore, an electric circuit for executing an operation of the arm can be simplified extremely, and the production efficiency is also improved. |
