| 摘要 |
PROBLEM TO BE SOLVED: To improve strength and accuracy of a resin cage that is manufactured by injection molding of a thermoplastic resin in which a reinforcing fiber is filled and an elastomer is blended.SOLUTION: A resin cage comprises: pole radial direction ribs 7 in which a rib R for connecting between an internal diameter side circumferential wall 5 and an outer diameter side circumferential wall 6 is formed at a portion connected by poles 4, 4, ... of rings 2, 3; a pocket part mid-diameter direction rib 8A provided in the circumferential direction center between adjacent pole radial direction ribs 7, 7; and an oblique direction rib 9 for connecting an intersection between the internal diameter side circumferential wall 5 and the pocket part mid-diameter direction rib 8A with an intersection between the outer diameter side circumferential wall 6 and the pole radial direction rib 7. A merging part of a melting resin is positioned in a radial direction rib 8B, so that a weld-line does not cross the rib and a weld cross section is increased, thereby improving strength. The oblique direction rib 9 is connected to the intersection between the internal diameter side circumferential wall 5 and the pocket part mid-diameter direction rib 8B, so that the weld inner diameter part of increasing a stress is made thick, thereby improving strength furthermore. |
