| 摘要 |
PROBLEM TO BE SOLVED: To provide a joint cross type universal joint for actualizing a construction to easily and compatibly secure the reliability and durability and reduce the size and weight by increasing the fracture strength when subjected to a great load.SOLUTION: The base end outer peripheral face of each shaft part 14 as part of a cross shaft 11a and a step face 30 as the outer face of a joint base part 15 are continuously joined via their concave surfaces 31a each having a partially circular cross section shape. The curvature radius of the cross section shape of each concave surface 31a is larger at the side of a front half 33 continuous with the outer peripheral face of each shaft part 14 and smaller at the side of a base half 32 continuous with the step face 30. In this construction, an increase in a curvature radius R of the cross section shape of a portion of each concave surface 31a where higher stress easily occurs during torque transmission, without an unnecessary increase in the length size of each shaft part 14, hardly gives damage such as crack to the base end of each shaft part 14. |
