| 摘要 |
PROBLEM TO BE SOLVED: To eliminate the necessity of post-machining for an inner peripheral part by forming a pair of bearing rings respectively fixed to the loading parts opposite in an axial direction of two members making eccentric rotations between each other to have no inner peripheries. SOLUTION: A bearing ring 4a (or a bearing ring 4b in a fixed side: the bearing rings 4a and 4b are similar in shape) in the turning side of a thrust ball bearing is formed by press-machining a steel plate billet, and a plurality of recessed bearing surfaces 4a1 (4b1) are formed in one end surface thereof. Each bearing surface 4a1 (4b1) is annular in shape, and a ball disposed in each bearing surface 4a1 (4b1) is rolled on the pitch circle PCD of the bearing surface 4a1 (4b1) following the eccentric rotation of a turning scroll member. This bearing ring 4a (4b) is formed to have no inner periphery without punching a center part. Thus, material yield is improved, and since no post-machining is necessary, machining is simplified. |
