TRIPOD JOINT

PURPOSE: To reduce joint exciting force and enable joint elements such as journal, roller, etc., to be stably placed. CONSTITUTION: This tripod joint has an outer joint 33 which has recess parts 34 placed in three circumferential directions and the recess parts 34 form a facing tracks in the circumferential direction and has a inner joint 31 with star shape section which has a journal 32 placed in three circumferential directions. The journal 32 is engaged with the inside of the recess part 34 of the joint 33 and the roller installation is supported by the journal 32. When the joint is extended to transmit torque, the vertical distance of the synthetic force K1 directly applied on the roller 38 from the inner joint 31 between first point-out faces from the joint axis line is smaller than the opposite synthetic force K2 applied on the roller 38 from the outer joint 33. When torque is guided inside the joint, tilting moment is generated against the roller 38 in any bending angle within the motion range.