Electro-hydraulic two-stage proportional directional control valve

摘要

The invention relates to an electro-hydraulic two-stage proportional directional control valve with a pilot stage and a main control stage. To avoid the effects of friction and problems which can arise from pressure-dependent adjustments, the main control piston is designed as a follow-up piston in which the pilot piston is guided, which in addition is provided with thread-shaped control edges and is driven via a stepping motor.