| 摘要 |
<p>PURPOSE:To obtain a smooth speed change characteristic by setting a target engine speed higher in accordance with the increase in the opening of an accelerator when the opening is in a range above a defined opening while, on the other hand, setting the target engine speed higher in accordance with the decrease in the accelerator opening when the opening is less than the defined opening. CONSTITUTION:A continuously variable transmission T consisting of a constant delivery type hydraulic pump P driven by an engine E and a variable displacement hydraulic motor M for driving wheels W has two speed change servo valves 30, 50 linked together by a link mechanism 45 as an actuator for carrying out change gear ratio control. These servo valves 30, 50 are controlled by duty- ratio controlling solenoid valves 151, 152 by means of a controller 100. In this case, in the controller 100, when an accelerator opening is above a defined opening, a target engine speed is set to be increased in accordance with the increase in the opening while, on the other hand, at the time of less than the defined opening, the target engine speed is set to be increased in accordance with the decrease in the opening.</p> |
