METHOD FOR MANUFACTURING SYNTHETIC RESIN RETAINER FOR BALL BEARING

摘要

PROBLEM TO BE SOLVED: To enhance durability in constitution wherein two gates are arranged when a synthetic resin retainer for a ball bearing is subjected to injection molding by relatively largely taking the positional shift quantity of a confluent part from the most thin-walled part of a pocket while suppressing deterioration of the fluid balance of the molten resin injected from the gates.SOLUTION: In a method for manufacturing a synthetic resin retainer 1 for the ball bearing wherein an odd number of pockets P for holding the balls for the ball bearing are provided at an equal interval in a circumferential direction, the gates for filling the cavity of an injection mold with the molten resin are provided at the positions corresponding to two pillar parts 4 and 4 sandwitching an odd member of the pockets P. One of two gates G1 and G2 is deflected to one side in an axial direction while the other one of two gates G1 and G2 is deflected to the other side in the axial direction.