| 摘要 |
<p>PURPOSE:To prevent the generation of noise and to reduce the number of assembling processes by providing a gap regulating means to restore a gap between a thrust bearing and a thrust seat to zero by means of slip torque exerted on the gap therebetween. CONSTITUTION:Since the friction factors of the surface of thrust seats 8 and 8a and the screw surface of a screw means 81 are regulated, slip torque between thrust bearings 7 and 7a and the thrust seats 8 and 8a is increased together with a thrust load increased by an impulsive force. Therefore, the thrust seats 8 and 8a are rotated by means of the increasing slip torque and protruded in the direction thrust bearings 7 and 7a through the screw action of the screw means 81, a gap therebetween is automatically reduced to zero, and the generation of noise is reduced. Besides, since when the gap is reduced to zero, no impulsive force due to collision is generated, slip torque by means of which the thrust seats 8 and 8a are only rotated is not generated. This constitution prevents a thrust seat from protruding more than necessary and the generation of an excessive thrust load, and maintains a gap at a constantly optimum value.</p> |
