Hydraulic control device for damping travel vibrations of mobile work apparatus involves hydro-cylinder supporting work tool, cylinder chambers of which are connectable via control valve arrangement with pressure medium source or tank

摘要

The hydraulic control device for damping travel vibrations of a mobile work apparatus involves a hydro-cylinder (2) supporting a work tool, the cylinder chambers (12,14) of which are connectable via a control valve arrangement (4) with a pressure medium source (6,10) or a tank (T). A damping valve arrangement (8) connects the one cylinder chamber (12) with a hydro-accumulator (10) and the other cylinder chamber (14) with the tank. The damping valve arrangement has a valve (34) for influencing the pressure in the hydro-accumulator and a check valve (30) for prevention of a back flow of pressure medium from the hydro-accumulator to the cylinder chamber. The check valve is between the one cylinder chamber and the valve. The latter valve has a pressure limitation function, via which when a limit pressure is exceeded pressure medium is fed away from the hydro-accumulator to the tank.