| 摘要 |
<p>The invention relates to a circuit arrangement for operating a hydraulic torque wrench or similar, comprising a piston-cylinder unit (18) that can be controlled at a predetermined pressure by a pump (11). Said arrangement is characterised in that the piston-cylinder unit (18) can be controlled by the pump (11) by means of a proportional valve (12) which acts both as a reversing unit between the forward and return travel and as a pressure control valve.</p> |
