| 摘要 |
<p>PURPOSE:To make it possible to prevent an engine stall due to a delay in response by hydraulic circuit by changing over a hydraulic clutch which is controlled in several control modes, into a hold mode during specific decelerating operation when the hydraulic clutch is controlled in a drive mode. CONSTITUTION:A belt drive type continuously variable transmission 2 is composed of a primary pressure control valve 44 as a speed change control valve, a constant pressure control valve 48, a line pressure control valve 54 and a clutch pressure control valve 62 in a hydraulic circuit, and the valves 44, 54, 62 are controlled by a control section 90 through solenoid valves 52, 60, 68, respectively. The clutch pressure control valve 62 is provided so as to control the clutch pressure of a hydraulic clutch 74. In this arrangement, the control section 90 enables the hydraulic clutch 74 to be controlled in several control mode, and if the clutch 74 is controlled in a drive mode selected among the above-mentioned several modes, when the vehicle falls into specific decelerating operation, the hydraulic clutch is turned into a hold mode, thereby it is possible to prevent a delay in response by a hydraulic circuit after the specific decelerating operation.</p> |
