| 摘要 |
<p>This invention relates to a stepless belt transmission (30) which is applied mainly to an automatic transmission mounted on an automobile and which has a pressure regulating cam mechanism (34) adapted to apply an axial force, which reflects the driving torque, to a pulley (31). The transmission (30) can prevent the occurrence of an excessive belt pressing force in the operational condition with a low transmission gear ratio. A retainer (1a) is fixed to a boss part (b) of a fixed sheave (31a), and a spring (1b) consisting of a plurality of disc spring members is provided on the outer circumferential surface of a boss part (n) of a movable sheave (31b) so that the spring (1b) can contact the retainer (1a), said retainer (1a) and said spring (1b) together forming a spring means (1). Owing to this arrangement, the engagement of the spring (1b) with the retainer (1a) in addition to the axial force generated by the pressure regulating cam mechanism (34) causes an urging force to occur in a deceleration region in which the transmission gear ratio is high, whereby a required belt holding force is secured. In the operational condition in which the transmission gear ratio is low, the length of the spring (1b) becomes close to a natural level, and the spring (1b) then leaves the retainer (1a), so that the axial force is applied by the pressure regulating cam mechanism alone.</p> |
