| 摘要 |
A hydraulic control device for automatic transmission, having a normally closed-type linear solenoid valve as a throttle valve (22). During an all-off fail, a switching valve (26) is switched by a normally-open solenoid valve (S1) so as to connect an input port (26l) and a first port (26j). Modulator pressure is supplied to a discharge port (22c) for the throttle valve (22), via the input port (26l) and the first port (26j). When the throttle valve (22) is fully closed, the discharge port (22c) and a output port (22b) are connected, the modulator pressure is supplied to a control oil chamber (20c) for a primary regulator valve (20), and the line pressure is regulated. As a result, the minimum line pressure can be set low, without taking into consideration when the throttle valve is fully closed, and power consumption can be reduced. |
