| 摘要 |
PURPOSE:To enhance both the accuracy of controlling line pressure through reduction in the control gain of a line pressure regulating valve and fuel consumption by switching pressure-modifier-valve source pressure according to whether or not lockup is being executed. CONSTITUTION:A hydraulic control device for a continuously variable transmission having a hydraulic power transmission 12 equipped with a lockup mechanism has a pressure modifier valve 116; a line pressure regulating valve 102 to which pilot pressure is supplied from the pressure modifier valve; a clutch relief valve 122 which supplies the output pressure of the line pressure regulating valve to the pressure modifier valve 116 as source pressure; and a lockup switching valve 128. The lockup switching valve 128 is turned on during lockup to switch the source pressure of the pressure modifier valve 116 to low pressure and, when lockup is not executed, the valve 128 is turned off to switch the source pressure to high pressure. |
