Multi-stage control valve for underground shield and support construction for mining applications, has a pre-control valve stage in the form of a pneumatic valve that is controlled by an electric actuator

摘要

Multi-stage control valve for use in underground shield and support construction has an electrically driven actuator, a pre-control valve stage (11) that is driven by the switching position of the actuator and a hydraulic main valve positioned after the pre-control valve stage. The valve of the pre-control valve stage is a pneumatic valve (20) that is controlled by the actuator (30). The invention also relates to a corresponding shield or support construction for underground mining constructions.