| 摘要 |
<p>PURPOSE:To make the device compact and to realize highly accurate control of tape tension by absorbing load variation caused by passing of a tape through a running system and load variation caused by variation of contact conditions between a tape and a cylinder. CONSTITUTION:In order to adjust rotation phases of a cylinder and a capstan (phase control), quantity of phase deviation between a reference signal generated by a cylinder PG and an output signal of FG1 are calculated and added to quantity of a speed error to make an error signal of the capstan. Also, at the same time, a CTL signal is recorded at a prescribed position on a tape. Quantity of controlling the capstan obtained by these procedure is sent to a reel control system, compared with an output signal of a reference quantity setting section 10, and the difference is outputted from a subtracter 11. Thus, variation part of tape tension is obtained, a prescribed bias value is added to this variation part via a bias adding means 13, the resultant signal is converted by a PWM means 14, and outputted as quantity of controlling reel driving.</p> |
