| 摘要 |
PROBLEM TO BE SOLVED: To reduce the weight as well as to obtain the sufficient strength by setting the outside diameter of a ball of a joint and the wall thicknesses of an outer race and a track part to the values in the specified range. SOLUTION: The diameter of a ball of a double offset-type constant velocity universal joint is taken as (d), and the wall thickness of a part of an outer race to be brought in contact with the ball is taken as (t), so as to satisfy the relationship; 0.21<=(t)/(d)<=0.30. A plate material having the specified thickness is pressed, heat-treated, namely, curburization- hardened and tempered, and an outer race of a double offset-type constant velocity universal joint is manufactured. The surface hardness of the outer race is made in the range of H..58 to 64, and the thickness of a track part and the wall thickness of the inside diameter part are equal to each other. A slide-type constant velocity universal joint is formed by using six balls each of which has the diameter in the range of 13 to 19.5mm. With the lower limit of the wall thickness of the outer race, the (t)/(d) ratio is set to 0.21 or more from the relationship between the failure strength of the outer race of the joint and the failure strength of a shaft. With the upper limit of the wall thickness, the (t)/(d) ratio is set to 0.3 or less since it is necessary for the wall thickness to be set to the mean thickness of the outer race in order to reduce the weight, the (t)/(d) ratio is set to 0.3 or less. |
