| 摘要 |
PURPOSE:To transmit the trip torque which is different according to the direction of revolution by arranging a plurality of ball holding holes on the concentric circles having different diameters and forming the ball relief parts in the same direction for the holding holes on the same circle and in the opposite direction for the holding holes on different circles. CONSTITUTION:On the first and second ball holding holes 12 and 13, ball relief parts 14 and 15 are formed in the counterclockwise direction (arrow X) side and clockwise direction (arrow Y) side of the holding holes 12 and 13, respectively. When a rotary shaft A normally revolves (arrow X), and a driven plate 16 is applied with a prescribed load torque, the ball 23 on the holding hole 13 runs over the relief part 15 and slips off, and the ball 22 in the other holding hole 13 runs over the opposite side of the relief part 14, and a large slip-off resistance is generated, and the product of the slip-off resisting force and the radius (r<a>) of a circle S<a> becomes nearly equal to the max. driving transmission torque. In the reverse revolution (arrow Y), the product of the radius r<b> of the circle S<b> and the slip-off resisting force of the ball 23 becomes the max. driving transmission torque. If the slip-off resisting force of the ball is equal in any case, the trip torque differs according to the direction of revolution.
|
