Patent ID: 6832806
Filing Date: 2004-12-21
Classification: B60J,F15B

Abstract:
Hydraulic actuating device for a device having a first and a second hydraulically moveable component, wherein said hydraulic actuating device comprises:a first and a second hydraulic actuator, respectively for moving the first and second moveable components, the first and second actuators each having a housing in which there is a space in which a piston and piston rod assembly can move in a reciprocating manner, with a piston and a piston rod which is coupled to the piston and projects out of the housing, the piston delimiting a first working chamber and a second working chamber in the housing, and the housing being provided with a first and a second connection, which are respectively in communication with the first and second working chambers in order to supply and discharge a hydraulic fluid in order to displace the piston and piston rod assembly, a connecting line which forms an open connection between the second working chamber of the first actuator and the first working chamber of the second actuator, a pump having a delivery port and a suction port, a reservoir for the hydraulic fluid, the suction port of the pump being connected to the reservoir, a valve assembly, wherein the valve assembly selectively: connects the first connection of the first actuator to the reservoir, or to the delivery port of the pump; and wherein the valve assembly selectively: connects the second connection of the second actuator to the reservoir, or to the delivery port of the pump, independent of the connection of the first connection of the first actuator to the reservoir or to the delivery port of the pump; and wherein the valve assembly selectively: connects the connecting line to the reservoir, or connect the connecting line to the delivery port of the pump, or makes the connecting line, the second chamber of the first actuator and the first chamber of the second actuator a closed volume, independent of the connection of the first connection of the first actuator to the reservoir or to the delivery port of the pump and independent of the second connection of the second actuator to the reservoir or to the delivery port of the pump.