| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide the hydraulic circuit of an automatic transmission, compulsorily unlocking a lockup clutch without requiring operation by a driver even when the lockup clutch of a torque converter is locked in an engagement state. <P>SOLUTION: The hydraulic circuit of the automatic transmission includes: an LC control valve 124 controlling engagement of the lockup clutch by supplying hydraulic pressure to and discharging the same from an oil chamber 20c1 of the lockup clutch; an LCC linear solenoid valve 142 controlling the operation of the LC control valve; a DR regulator valve 94 controlling hydraulic pressure to a cylinder chamber 30b1 of a power transmission adjusting member and the like; a DRC linear solenoid valve 104 controlling the operation of the DR regulator valve; and a B/U (switching) valve 150 intervened before the oil chamber 20c1 of the lockup clutch 20c. The DRC linear solenoid valve, when the LC control valve or the like has failure, the lockup clutch is detected to be locked in the engagement state and energization is stopped, operates the B/U valve to disengage the lockup clutch. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
