| 摘要 |
PURPOSE:To perform smooth lockup even during a coast state by a method wherein during a coast state being the inertia state of a vehicle, an engagement pressure exerted on a lock up piston is controlled to a value higher than the engagement pressure by boosting the engagement pressure of a torque converter. CONSTITUTION:In a torque converter 4, an input element driven by an engine 1 and an output element driven through fluid stirred up by the input element are engaged with and disengaged from each other through a lockup clutch by a lockup piston 3. In this case, it is detected by a coast state detecting means 42 whether a vehicle is in a coast state defined as the inertial state of a vehicle. When the coast state is detected, the engagement pressure of the lockup clutch is boosted by a hydraulic control means 43. When the coast state is detected, a vehicle may follow proper liquid pressure data of a proper liquid pressure data table 44 based on the input output speed ratio of the torque converter 4 detected by an input output speed ratio detecting means 41. |
