| 摘要 |
<p>A fluid flow control valve and method for operating which maintains the rate of flow of fluid therethrough at a substantially constant rate regardless of variations in pressure of the fluid flowing therethrough. The fluid flow control valve (10) comprises: a) a retainer (50) extending along an axis (A) from a fluid flow open end (51) to a second end (52); b) an inner spool (12) extending along the axis (A) and having (i) an axial passageway, (ii) and a first section (21) slideably cooperating with a cylindrical wail surface (53A) of the retainer; c) an outer spool (13) extending along said axis (A) sliding between an inner cylindrical wall surface (53B) and the inner spool and operable to close a radial port (56) when aligned therewith; d) a spring (90) yildingly urging the outer spool (13) away from the open end (51). A flow rate is set by the inner spool (12). A change in pressure will unbalance the forces working on the outer spool (13) and cause it to move to increase or decrease the opening of the radial port (56).</p> |
