| 摘要 |
PURPOSE:To stop the movement of a tone arm and to drop it smoothly without an overrun of the inertia force by decelerating gradually the moving speed of the tone arm by the slit output to shift the arm to its dropping position. CONSTITUTION:For playing a 30cm record, a slit plate 2 moves together with a tone arm 1. When a photointerrupter 4 reaches a position C on the plate 2, the interrupter 4 detects the light with the rise of the light and delivers the detection signal to a control circuit 5. With this signal, the circuit 5 decreases gradually the time of the high-speed and forward revolution signal and increases gradually the time during which said revolution signal is not delivered for an arm motor. Thus the arm 1 is gradually decelerated. When the plate 2 moves and the interrupter 4 reaches a position D on the plate 2, the interrupter 4 detects the light and delivers it with the rise of the light. Then the movement of the arm 1 is stopped and dropped by the circuit 5.
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