| 摘要 |
<p>A STEERING SYSTEM AND COMPENSATING VALVE A hydrostatic power steering control system with variable feedback compensation employing a unique compensating valve. The steering control system includes first and second hydraulic cylinders, each having two internal chambers denoted as head and feedback chambers. A piston is movably retained in each of the cylinders and is attached to a piston rod which extends outwards. The pair of piston rods are connected to a pair of steerable wheels by a mechanical linkage. Fluid contained in a reservoir is pressurized by a supply pump and is selectively passed to a head chamber of one of the cylinders by a control valve. The control valve is actuated by pressure differences in two interconnected fluid passages which connect to the feedback chambers of the two cylinders. A pressure difference in these passages is created by manually operating a steering wheel which actuates a metering pump positioned across the fluid passages. In order to alleviate pressure fluctuations between the two feedback chambers, a compensating valve and a pair of one-way check valves are connected across the fluid passages in a parallel relationship. The compensating valve allows pressurized fluid above a predetermined pressure range value to be relieved from the system, but does not limit a pressure value generated by the metering pump.</p> |
