| 摘要 |
PROBLEM TO BE SOLVED: To perform manual operation in emergency easily and safely even in an operation cylinder provided with two operation chambers with different volumes in the piston side and the piston rod side. SOLUTION: The double-acting hydraulic operation cylinder 3 for a device operating a hatch back of a vehicle hydraulically is connected by a hinge to the vehicle in one side and to a cover flap in the other side. The operation chambers 8, 9 are connected to each side of a pressure source 12 which can be switched. Both check valves are provided with a reciprocal cut-off release device and each operation chamber is held at a fixed pressure level through preload valves 15, 16 to control the flow into a tank. The separate suction pipe 23 for filling is open to a tank 17 between at least one operation chamber and a check which can release the cutoff, and a check 24 to be opened to the operation chamber is inserted into this suction pipe 23 for filling. |
