Differential hydraulic circuit for feed and locking up of controlled double acting jack

摘要

The differential hydraulic system controls a jack (3). A hydraulic power source (1) supplying a fluid. A distribution valve (2) feeds the jack via a supply feed (4) and a return feed (5). A compact feed differential unit (9) is interposed between the feeds. This unit is actuated in view of the extension of the rod (3a) of the jack. The unit is arranged to directly transfer oil contained in the chamber (B) of the jack towards the chamber (A) of the jack. The chamber (B) is situated on the rod side, whilst the chamber (A) is situated on the opposite side of the piston (3b) of the jack. This is done without returning to the distribution valve and thence to the power source thus reducing the power of the installation. An accumulator (31) can be installed in the circuit to reduce any shocks experienced by the double acting jack.