| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic control device in which optimum working pressure can be generated even at the time of L/U On and slip or the like of a belt can be avoided by introducing a working pressure control of a belt tpe CVT or the like, having an L/U control function. SOLUTION: A controller 17 of a CVT in which a V-belt 3 is set over between two pullets 1, 2 performs a stepless change control of the gear ratio using a belt transmission mechanism operated oil-hydraulically and also performs an L/U control. The engine speed drops at the time of L/U On and an inertial torque is generated corresponding to the revolutions, and therefore, the line pressure is increased accordingly. In there is no main line pressure Up corrective control at the time of L/U On changing-over, the L/U On oil pressure goes in shortage, and the belt is likely to make slippage, but such occurrence can be prevented according to this configuration. The increase of the line pressure can be established certainly in an amount corresponding to the inertia torque, and a slip, etc., of the V-belt 3 can be avoided properly even at the time of L/U On, and it is possible to establish an optimum line pressure control of the CVT on L/U system. |
