| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem that a conventional front housing 18 needs to be made of metal of high cost because the front housing 18 is deformed together with a ring gear 27 due to internal stress of the ring gear 27, despite a demand for the ring gear 27 retained by the front housing 18 made of resin. SOLUTION: An outer peripheral edge of the ring gear 27 is securely retained by the front housing 18 made of resin from an outer peripheral side. A fiber substance is arranged inside resin material forming the front housing 18 in a direction B perpendicular to a direction A to which a diameter of the ring gear 27 extends. Since the front housing 18 is the resin material, contraction force is generated when the resin is hardened after molding. Although the resin is hard to contract in an arranging direction B of the fiber substance, the great contraction force is generated in a direction D perpendicular to the arranging direction of the fiber substance. Thus, ovality of the ring gear 27 can be suppressed, and the ring gear 27 can be kept in a state of a perfect circle. COPYRIGHT: (C)2005,JPO&NCIPI |
