| 摘要 |
<p>PURPOSE: To suppress a displacement amt. of a rotary shaft and to prevent friction and noise and deterioration of efficiency by holding one end of the rotary shaft in the whole radial direction. CONSTITUTION: An output of a motor is decelerated through a worm 4, a worm wheel 2b, a worm 2c, a worm wheel 5, a spur gear 6 and a spur gear 7, and is transmitted to a magnetic tape moving mechanism. In a holding structure of the rotary shaft 2a in the radial direction, one end of the rotary shaft 2a is held by 1a, 1b, 1c and 1d and in the whole radial direction, and holding positions of holding fulcrums 1a and 1b are deviated in some measure in the direction of the rotary shaft, thus eliminating dimensional backlash in the direction of A at the time of operation after fitting the rotary shaft 2a. In a holding structure of this rotary shaft 2a in the thrust direction, both ends of the rotary shaft 2a are borne by 1h and 1i. Then, the other end is held by 1e, 1f and 1g and in the radial direction other than the A direction, and is free in only one direction of the A direction (in the direction of meshing with the worm on the upstream side). Consequently, the still one end of the rotary shaft 2a can be set up in the direction from A.</p> |
