| 摘要 |
<p>PROBLEM TO BE SOLVED: To conduct speed change control for a continuously variable transmission regardless of the slip state of a start clutch. SOLUTION: When a start clutch 7 presents no slip, the target NP for an input pulley 11 is set based on the rotation speed of an output pulley 12 related to vehicle speed and the required load, and the speed change ratio of a CVT 5 is controlled so that the input pulley 11 attains the target NP. When the start clutch 7 presents slip, the target NP for the input pulley is set so that the current target change gear ratio is maintained, the change gear ratio of the CVT 5 is controlled so that the input pulley 11 attains the target NP. When the start clutch presents slip more than a prescribed value, the rotation speed of the output pulley 12 is stabilized, the change gear ratio of the CVT 5 is controlled by setting the target NP of the input pulley 11 properly. As the result, the speed change control for the CVT 5 is enabled regardless of the slip state of the start clutch 7.</p> |
