| 摘要 |
<p>PURPOSE:To record and reproduce high-quality pictures, by providing a pump-out spiral groove on one face of end faces facing to each other of cylinders. CONSTITUTION:A pump-out spiral groove 18 is provided on the lower end face of an upper rotary cylinder 2. When the upper rotary cylinder is rotated, air inside the cylinder is discharged to the outside. Air discharged to the outside by the spiral groove 18 gives a floating force to a magnetic tape to form a uniform air film throughout the part, where the magnetic tape slides, on outside circumferential faces of the upper rotary cylinder 2 and a lower fixed cylinder 3. The sliding contact between the magnetic tape and the rotary head assembly is avoided to realize stable and smooth tape running.</p> |
