| 摘要 |
<p>PURPOSE:To make a recording/reproducing device high in reliability and high in performance by preventing a tape from sticking to a cylinder at the rotating side and suppressing the deterioration of a jitter performance. CONSTITUTION:The rotating upper side cylinder 5a consists of a cylinder part having the equal diameters and a taper part 5f extended to the lower side cylinder (not shown in the figure) from the cylinder part while forming the diameters to be gradually smaller. At the tape entering side, the magnetic tape comes into contact with almost the whole height of the upper side cylinder 5a, meanwhile, it comes into contact with the lower part of the upper side cylinder 5a at the tape exit side. A window part 5e for projecting a rotary head (not shown in the figure) to the outside is provided on this taper part 5f. The surfaces of the cylinder part and the taper part 5f are roughened, but these surface roughness are made different from each other by separating at the border 5d between the cylinder part and the taper part 5f, and in this instance, the surface of the taper part 5f is made smoother than that of the cylinder part like as the surface roughness of 0.4S for the cylinder part and 0.1-0.2S for the taper part 5f.</p> |
