| 摘要 |
<p>A control system for controlling the pressure and pressure balance in two separate-fluid pressure circuits (2,8). A valve (10) being employed which comprises a balance piston (2') and a regulating piston (3'). Each of the pistons controls a connection of the first and second fluid pressure circuits to a respective relief line (15,20). Fluid pressure is applied to the regulating piston (3') to regulate the pressure in one circuit (8) and the balance piston regulates the pressure in the other circuit in relation to that regulated by the regulating piston. A three position switch (32) and two air pressure regulators (30,31) or a three position switch, (5), two potentiometers (PC, PL) and a servo control valve (201) control the pressure applied to the regulating piston to control the pressure required in the first and second circuits for the desired modes of operation. A further balance valve (40) may be disposed between the first and second circuits.</p> |
