| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce or alleviate a peak of stress in association with an increase of surface pressure acting on a pressure-insertion face of a ring gear, so as to improve durability.SOLUTION: A ring gear 10 is fit to the external peripheral side of a support part 8 having an external peripheral face 9 formed in a circular shape; the ring gear 10 is made to abut on a stopper 11 which is formed at one end of the external peripheral face 9 in the axial direction while protruding to the outside from the external peripheral face 9 in the radial direction; and a thrust load of the ring gear 10 is made to act on the stopper 11. A groove 14 recessed to an internal peripheral side in the radial direction is formed at a portion at the stopper 11 side of the external peripheral face 9; a portion at a side opposite to the stopper 11 with the groove 14 of the external peripheral face 9 interposed is made to be the pressure-insertion face 20 to which the ring gear 10 is pressure-fit and adhered; and prescribed clearances C1, C2 are formed between a boundary 21 of the groove 14 and the pressure-insertion face 20 and the internal peripheral face 18 of the ring gear 10 in radial/axial directions of the external peripheral face 9.</p> |
