| 摘要 |
<p>A valve for use in controlling a plurality of fluid operated functions, for example the functions of a hydraulic mine roof support, comprises a valve body 10, a plurality of valve members 13 each movable independently to carry out a fluid flow control function, a plurality of valve actuating members 21, movable in a direction tending to actuate the valve members 13, and an interposer device 25 movable to prevent at least one of the valve actuating members 21 from actuating its associated valve member 13, thus enabling the valves to be selectively operable.</p> |
