| 摘要 |
<P>PROBLEM TO BE SOLVED: To form a second hydraulic pump 22 of an electric type compact by using a first hydraulic pump 21 of a mechanical drive type while traveling by a motor as well. <P>SOLUTION: The first hydraulic pump 21 of a mechanical drive type is connected to the drive wheel side of a clutch, and it is constantly driven when a vehicle travels even in traveling by a motor. A first hydraulic passage 63 including the first hydraulic pump 21 and a second hydraulic passage 64 including the second hydraulic pump 22 are selectively switched by a first and a second electromagnetic changing valve 61 and 62. When the second hydraulic pump 22 is actuated, the first hydraulic passage 63 is disconnected from a hydraulic supply system. In backward traveling as traveling by a motor, the first hydraulic pump 21 is rotated inversely, but since working fluid circulates through a circulation passage 67 provided with a check valve 68, loss caused by pump-driving is minimized. <P>COPYRIGHT: (C)2004,JPO |
