| 摘要 |
<p>PURPOSE:To more efficiently reduce a friction coefft. on a tape guide body capable of diminishing a traveling load of a magnetic tape by vibrating the tape guide body and diminishing an actual contact area with the magnetic tape. CONSTITUTION:The tape guide body 52 is composed of a piezoelectric element, and its outer circumference and inner circumference are provided with electrodes so as to change the outer diameter of the tape guide body 52 in accordance with a voltage to be impressed. Then, a circuit 90 for driving this tape guide body 52 is provided, and its driving signal waveform is formed into a square wave, and also a period for diminishing the outer diameter of the tape guide body 52 is regarded as a length of 40 to 65% of one cycle of the driving signal waveform. Then, a tape tension detecting part, a tape speed detecting part and a driving waveform deciding part are provided, so that the driving signal waveform can be decided from tension and speed information.</p> |
