| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the durability of a ring to input a return spring force to a push rod and transmit the pressing force of a piston to the push rod. SOLUTION: In the non-operational condition of a band servo, a piston 8 is detached from a ring 15, and a gapγis present between the two. The ring 15 is displaced at the critical position in the width of an engagement groove 6a, and brought into contact with a corresponding side wall of the groove 6a, and the ring 15 is in a loaded condition. The ring 15 is also in the loaded condition when a push rod 6 is projected by the piston in the transmission to the second shift. The ring 15 is also in the loaded condition in the transmission to the third shift since the band servo is returned to the non-operational condition. In the transmission to the fourth shift, the band servo is in the condition where the push rod 6 is projected by the piston 8, and the ring 15 is detached from the side wall of the groove 6a by the piston 8 in the no-load condition. Thus, the ring 15 is subjected to the load fluctuation during the transmission to the fourth shift low in frequency of generation, and during the transmission from the fourth shift, and the early degradation of the ring can be avoided.</p> |
