| 摘要 |
<p>PURPOSE:To cause the inside of an air accumulator to be negative pressure or over pressure and to maintain stable traveling while keeping non-contact between a tape and a drum by forming the air accumulator in a recessing shape on the surface of one drum, at least, out of the upper drum and lower drum of a revolving head. CONSTITUTION:A contact surface with a tape 4 is formed on a surface 2 of an upper drum 1 in the revolving drum, which is provided in a car digital audio tape recorder, and a bag-shaped air accumulator 3 is formed on the whole surface 2 of this upper drum 1. The upper drum 1 in the surface structure of the drum for revolving head is revolved in an arrow (a) direction and the tape 4 is traveled in an arrow (b) direction. Then, air 5 between the upper drum 1 and tape 4 flows in an arrow (c) and the numberless air accumulators 3 are formed on the surface 2 of the upper drum 1. Then, the air 5 is suitably taken-in, an air layer is generated and the tape 4 maintains the stable traveling in noncontact with the upper drum 1.</p> |
