| 摘要 |
<p>PURPOSE:To avoid the damage to tape even if the tape is repidly and intermittently fed, by controlling the reel motor in response to acceleration and deceleration of a tape and absorbing the force caused through the acceleration and deceleration of tape. CONSTITUTION:The magnetic tape 21 of a recording and playback device is wound over the range of angle of 180 deg. or more on the rotating drum 10 through guides 51-54 from a reel 30, and reaches a reel 40 through being clipped with a capstan 70 and a pinch roller 80 via guides 55 and 56. Further, the recording and playback device consists of reel motors 31, 41, magnetic sensor 116, position amplifier 117, phase compensation circuit 118, and differential amplifier 42. Further, the output voltage of the magnetic sensor 116 is given to the differential amplifier 42 through the phase compensation circuit 118 from the amplifier 117. Next, the reference voltage from the power supply 43 is given to the differential amplifier 42, the difference of the both is delivered to the reel motor 41 to obtain constant elongation of spring, enabling constant force at all times.</p> |
