| 摘要 |
<p>PROBLEM TO BE SOLVED: To maintain the long lifetime even in the condition that peeling and breakdown is generated line the case of ATF oil lubrication by regulating a ratio of a long diameter of a contact ellipse of an inner ring to a diameter of a rolling body and a ratio of the long diameter of a contact ellipse of an outer ring to the long diameter of the contact ellipse of the inner ring at the time of applying a basic operating rated load. SOLUTION: A contact ellipse S1 is formed in a contact part of a raceway groove M1 of an inner ring 1 with a ball 3 having a diameter DW, and a contact ellipse S2 is formed in a contact part of a raceway groove M2 of an outer ring 2 with the ball 3. At the time of applying a basic operating rated load, a ratio of the long diameter Ba of the contact ellipse S1 to the diameter DW of the rolling body 3 is set so as to satisfy a relation that 0.25<=Ba/DW<=0.35, and a ratio of the long diameter Aa of the contact ellipse S2 to the long diameter Ba of the contact ellipse S1 is set so as to satisfy a relation that 0.6<=Aa/Ba<=0.9. At the time of ATF oil lubrication, the tangent force to be generated in a contact area even in the condition that the peeling and breakdown can be generated is restricted by regulating the ratio to the contact ellipse, and the lifetime can be prolonged by restricting the generation of heat.</p> |
