MANUFACTURING METHOD FOR BEARING CAGE

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method for a bearing cage which can suppress the lowering of rigidity.SOLUTION: A region between adjacent resin injection gates 51 is divided into first to third regions S1 to S3. Three pieces of the resin injection gates 51 are arranged in positions which are deviated to one side of a peripheral direction from a center of the peripheral direction of each column 20 so that numbers of pockets 30 in the first to third regions S1 to S3 become equal. A resin sump 40 which can store a molten resin is arranged in the center of the peripheral direction of the column 20 which is most separated from both ends of the first to third regions S1 to S3. A cross section area of a communication part 42 of the resin sump 40 communicating with the column 20 is not larger than one quarter of a cross section area of the resin injection gate 51.SELECTED DRAWING: Figure 1