| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a problem of engagement of a hydraulic clutch by centrifugal hydraulic pressure without providing a device and a mechanism preventing influence of hydraulic pressure on the hydraulic clutch. SOLUTION: This power transmission is composed of a forward travel side power transmission system transmitting engine rotation driving force as a forward traveling side rotation, namely a power transmission system established by a forward traveling clutch 30, a reverse travel side power transmission system transmitting engine rotation driving force as a reverse traveling side rotation, namely a power transmission system established by a reverse traveling clutch 25, and the forward traveling clutch 30 of hydraulic operation type selecting and establishing the forward traveling side power transmission system. An engine output regulating device 50 operates to control engine revolution below a designated revolution under a condition that the forward traveling clutch is disengaged to release the forward traveling side power transmission system.</p> |
