| 摘要 |
<p>PROBLEM TO BE SOLVED: To put the reference edge of a magnetic tape to surely be along a lead of a lead ring in a rotating magnetic head assembly adopting a DD (dynamic drum) system. SOLUTION: When a rotary magnetic head assembly 10A is constituted by adopting a DD system, especially the sliding contact surface 14a for magnetic tape on an upper drum is cylindrically formed, whereas the side confronted with the upper drum 14 of the sliding contact surface 13a1 for magnetic tape on a lower drum 13 is formed to have nearly the same diametier as that of the sliding contact surface 14a for magnetic tape on the upper drum 14, and also by making the diameter gradually smaller than that of the sliding contact surface for magnetic tape on the upper drum going toward the side confronted with the bottom surface part 12c of a lead ring 12 to form a tapered conical shape, a force F is generated for pressing the reference edge (lower end part) Te of a magnetic tape T against a lead 12a of the lead ring 12.</p> |
