The hydraulic pressure is maintained at a hold pressure in the hydraulic control system by the auxiliary hydraulic pressurization system.

A hydraulic pump (50) provides a hydraulic energy supply for the hydraulic actuator (40).

The second set hydraulic pressure is set to be higher than the first set hydraulic pressure.

The hydraulic pump unit produces hydraulic pressure to supply it to the hydraulic actuator.

The hydraulic control device includes a hydraulic pressure generating unit (1), a hydraulic pressure control unit (2), a hydraulic pressure actuating unit (3) and hydraulic attachments.

A controller (43) controls an electric motor (18) on the basis of the hydraulic pressure detected by a first hydraulic pressure sensor (48) and of the hydraulic pressure detected by a second hydraulic pressure sensor (49).

The hydraulic section includes a piston that is moved under force of hydraulic pressure applied thereto from a hydraulic pressure source.

Hydraulic pressure test to check the operating pressure

A fluid pressure source (51, 59), provides fluid pressure for operation the clutch and brakes.

Burst test under hydraulic pressure

The hydraulic pressure is then removed.

area exposed to hydraulic pressure

The present invention relates to a hydraulic control valve for controlling hydraulic pressure within an actuator (8) by supplying or releasing hydraulic pressure to or from the actuator (8).

Operating the hydraulic recharging circuit in response to applying the hydraulic pressure and pressurizing the hydraulic accumulator in response to operating the hydraulic recharging circuit.

An auxiliary pressure system for a hydraulically actuated automotive automatic transmission (12) having a hydraulic fluid reservoir (30) and a line pressure circuit (28).