| 摘要 |
PROBLEM TO BE SOLVED: To improve durability by permitting the creep control of a continuously variable transmission having a infinite shift ratio only with the variable speed control of a variable speed mechanism, without depending on the slip control of a low clutch. SOLUTION: Although a power circulation mode is established by fastening the low clutch with N-D switching, the variable speed mechanism holds a shift ratio icvt=GNPRTO at a neutral point. The icvt=GNPRTO is continued in a stopped condition due to braking operation, but weak creep torque is generated and so a torque shift compensation amount TSRTOMFL is increased and a step motor is moved to a LOW side to generate output shaft torque. In Fig. (4), slight move-back due to a decrease in braking force is detected by the fact that a planetary gear set output rotating number Nr is less than 0, and a move-back integration amount INTGOUT2 showing a move-back distance is increased at a large rate in preset values TOUT1. The TSRTOMFL is increased therewith, the step motor is also moved further to the LOW side, and the output shaft torque is further increased to prevent the move-back of the vehicle. |
