| 摘要 |
<p>PURPOSE:To simplify the processing to make it possible to remove completely the float of a tape for VTR by providing a specific concave groove in the first regulation face side at the intersection part between the first and the second regulation faces which regulate the tape. CONSTITUTION:The spiral tape guide part 15 is formed within a range of approximately 180 deg. on the circumference face of the lower drum 13 which constitutes a rotary head drum together with the upper drum. The guide part 15 is obtained by forming the cylindrical first regulation face 18, which regulates the face of the tape 17, and the second regulation face 19, which regulates the edge of the tape 17 and is inclined vertically and spirally to the face 18, into one body by the bite processing. The concave groove 21 is formed in the face 18 side at the intersection part 20 of the faces 18 and 19, and the intersection part 20 and R generated there are put back from the face 18 by the step difference d components, so that the edge of the tape 17 can be prevented from being brought into contact with the R part. However, the concave groove 21 part b is processed by a sharp-tip bite different from the bite which processed the face 18 part a, so that the step difference d is small.</p> |
