Analysis of Primary and Secondary Thrusts for A Metal Belt CVT Part 1: New Formula for Speed Ratio-Torque-Thrust Relationship Considering Band Tension and Block Compression

摘要

In this paper, a new formula for calculating primary and secondary thrusts for metal-belt CVTs will be proposed considering variation of band tension, block compression and active arc for each of the primary and secondary pulleys. For the secondary thrust, an effective friction coefficient is introduced considering the effect of flange deflection. Nondimensional primary and secondary thrust of the metal-belt CVT by the new formula agree well with the experimental results except for low torque range, 0 <λ<0.2 at a speed ratio i = 1.0. The new formula can be used in design of the primary and secondary thrusts control system with sufficient accuracy.