摘要 |
<p>A multiple valve control device for use with a hydraulic walking mine-roof support frame, comprising a valve housing containing control valves which are disposed concentrically to a central axis around a central filter into which an axially-extending control-medium feed duct enters and from which radial bores extend in a star pattern towards the control valves, the said control valves, which are provided with valve pistons, being actuated via operating members from the valve-housing endface which is provided with a cover.</p> |