公开(公告)号：JPS5715245A

公开(公告)日：1982-01-26

申请号：JP8745680

申请日：1980-06-27

Applicant: SONY CORP

Inventor： MISAO IKUO ,  KUMAGAI TAKUYA ,  OOBA SHIYOUSUKE

IPC: B65H23/18 ,  B65H59/38 ,  G11B15/43

Abstract: PURPOSE:To exercise the best tension control while driving a take-up reel motor with minimum irreducible take-up torque, by supplying a specific feed-out current to a supply-side reel motor. CONSTITUTION:A driving current for a reel motor 1 at a tape take-up side is detected to supply a feed-out current, which corresponds to the detection output signal, to a reel motor 2 at a tape supply side. In the feedback servo loop, a current limiter circuit 23 which limits the maximum value of the said feed-out current is provided and its operation point is varied according to the rotational frequency of the reel motor 2. For example, the driving current for the motor 1 is detected in the form of a voltage drop across a resistor 21 and supplied to the limiter circuit 23 via a differential amplifier 22. Further, the rotational frequency of the motor 2 is detected by a frequency generator 24 and then converted 25 into a voltage signal, with which the operation point of the limiter circuit 23 is varied.

公开(公告)号：JPS5712430A

公开(公告)日：1982-01-22

申请号：JP8626780

申请日：1980-06-25

Applicant: SONY CORP

Inventor： MISAO IKUO ,  KUMAGAI TAKUYA

IPC: G11B15/00 ,  G11B15/43

Abstract: PURPOSE:To ensure assured detection for the slack of a traveling tape, by detecting the degree of inclination for reduction change of the rotating speed of a reel motor that drives a tape reel. CONSTITUTION:For instance, in a quick forward mode, the frequency signal is generated from a frequency generator 10 in accordance with the rotational frequency of a reel motor 2 of take-up side that is turning in a high speed and in the take-up direction. Then the fall differential output showing the degree of inclination of the frequency signal is delivered to a waveform shaping circuit 21 through a frequency- voltage converting circuit 13 and a differentiating circuit 20. The circuit 21 obtains the slack detection signal to actuate a stop controlling circuit 17 in case the reduction speed of the motor 2 exceeds the critical value. In such way, the slack of a traveling tape can be detected in an assured way.