Apparatus for adjust the position of a device provided with a multiplicity of hydraulic cylinders of adjustment

摘要

P invention concerns an apparatus for operating at a pressure of fluid. / p & & p & apparatus for adjusting, provided with a multiplicity of hydraulic cylinders of adjustment simultaneously supplied by the quantities of hydraulic fluid corresponding to the desired adjustment. Each hydraulic cylinder communicates with a respective displacement of a hydraulic pump which is common to all the cylinders. The pump comprises a cylinder and a piston rod is displaced axially inside it. The piston rod has a shape stepped in order to have a multiplicity of the surfaces of the piston annular and concentric and the inside diameter of the cylinder is shaped in a step of a corresponding manner. In front of each surface of the piston is thus formed a chamber for displacement and these chambers are isolated from each other during a working stroke of the pump. / p & & p & application to the height of the top of a table or other object / p