| 摘要 |
<p>PURPOSE:To shorten the positioning time of a head and to improve operability, by driving a motor at a high voltage up to before a target position of the head and driving the motor at a low voltage thereafter, and thus braking the motor excellently. CONSTITUTION:When a play switch PLAY is turned on, outputs of output lines 21 and 22 are held at L and H respectively and the motor rotates normally through a driving circuit 20 to allow the head to start moving. The output of an output line 27 is at L and a transistor (TR) 26 is also turned off, so the motor 1 rotates at a high speed at a 11.3V high voltage. In this case, a reflecting plate 17 also rotates and right after a position STOP, the photodetecting element of a photoreflector 18 receives light from the reflecting plate 17 to generate an output H. The reflecting plate 17 is rugged, so a control circuit 12 detects arrival at a position PAUSE to hold the output of the output line 27 at H. Then, the TR26 turns on and the output of a fixed voltage circuit 24 drops to 7V and the motor 1 rotates while having inertia reduced by low-voltage drive.</p> |
