Electrohydraulic speed control device for an hydraulic lifting cylinder

摘要

The arrangement comprises a single proportional valve (18) for lowering the cylinder, which is connected in a bypass conductor (17) led from the lift cylinder (11) to a pressure medium reservoir (13). A current sensor (25) is provided for measuring a current supplied to an electric motor (21) for operating a pressure medium pump when lifting the cylinder. The signals of the current sensor are processed by an electric control arrangement (22) for controlling the proportional valve, dependent on a load pressure in the lift cylinder, to enable a load pressure compensated control. An Independent claim is provided for a corresponding speed control method.