Patent ID: 6351944
Filing Date: 2002-03-05
Classification: E02F,F15B

Abstract:
A hydraulic control arrangement for a mobile working machine, in particular for a wheel loader, having at least one hydraulic cylinder (12) with the aid of which a working tool can be moved, comprisinga directional control valve (11) for controlling the hydraulic-fluid paths between a pressure chamber (15) of the hydraulic cylinder (12), a hydraulic-fluid source and a tank (27), a hydraulic accumulator (21) which is connectable to the hydraulic-fluid source via a filling valve (22; 71), located in a filling line (20), of which the charging pressure is increaseable to a limit pressure via the filling valve (22; 71) and which is connectable to the pressure chamber (15) of the hydraulic cylinder (12) for damping pitching vibrations of the working machine, and a shut-off valve (22; 75) which, with a first condition fulfilled, is moveable into a through position in which hydraulic fluid is flowable through it in the direction from the hydraulic accumulator (21) to the pressure chamber (15) of the hydraulic cylinder (12) and vice versa, wherein the shut-off valve (22; 75) is also moveable, with the first condition fulfilled, into its shut-off position when the load pressure in the pressure chamber (15) of the hydraulic cylinder (12) or the accumulator pressure reaches a maximum pressure.