| 摘要 |
<p>The invention relates to a hydraulic control valve assembly for controlling a consumer unit such as a servomotor of a vehicle steering system. The valve assembly has a conventional port arrangement which includes two selectively pressurizeable and drainable motor ports connectable to a servomotor and supply and exhaust ports connectable respectively to a pump and a drain tank. A slide valve has a central wall section between two motor ports which completely block a central supply port when the slide valve is in a neutral position. Two metering control load sensing ports are on opposite sides of the supply port and when the slide valve is in a neutral position the load sensing ports are in throttling relation to the slide valve motor ports. The load sensing ports are sufficiently closely adjacent the supply port that when in operation when the supply port is partially overlapped by one of the motor ports one of the load ports on the opposite side of the supply port is closed by the central section of the slide member.</p> |
