| 摘要 |
PROBLEM TO BE SOLVED: To prevent the temperature of a hydraulic oil from rising due to an increase in the heat generation of a torque converter when the temperature of the hydraulic oil is lowered by increasing the circulation flow to an oil cooler through the disengagement control of a lockup clutch. SOLUTION: Even when the temperature T<SB>OIL</SB>of the hydraulic oil is increased over a predetermined value T<SB>OIL</SB>1 when the lockup clutch is engaged in a lockup engagement area, the engaged state is maintained at a low load with a throttle valve openingθ<SB>TH</SB>equal to or less than a predetermined value so long as it does not meet the predetermined requirements for performing disengagement including cruising at an approximately constant vehicle speed and at an approximately constant throttle valve opening. When it meets the requirements for performing the disengagement (YES in the determination of S4), steps S5 and under are performed to disengage the lockup clutch. Consequently, the rise of the temperature T<SB>OIL</SB>of the hydraulic oil can be securely suppressed by the disengagement control of the lockup clutch. COPYRIGHT: (C)2007,JPO&INPIT
|
