| 摘要 |
<p>P I S T O N V A L V E A valve having separate closures for its inlet and its outlet respectively comprises a housing having the inlet in an elongated tabular wall and the outlet at an annular valve seat. A piston constituting one closure is movable coaxially within said wall so as to open and close the outlet. A sleeve constituting another closure is movable coaxially over the piston and within said wall so as to open and close the inlet. The piston and the sleeve are associated for interdependent movement.</p> |
