초록 ▼

A floating piston (54) has a valved (86) vent opening (88), with the vent opening closing (92) on movement of the piston. The piston is spring loaded (56, 58) to vent air, but seal fuel. Modulation of pressure in pressure resisting chamber (48) between pump discharge and lower pressures, provides co

A floating piston (54) has a valved (86) vent opening (88), with the vent opening closing (92) on movement of the piston. The piston is spring loaded (56, 58) to vent air, but seal fuel. Modulation of pressure in pressure resisting chamber (48) between pump discharge and lower pressures, provides control of the valve. Pressure difference (96, 62) and valve position (36) measurements provide flow measurement data.

대표청구항 ▼

A multiple function fuel valve comprising: a valve body having an inlet pressure chamber at one end, a resisting pressure chamber at the other end, and a central piston receiving compartment between said chambers; a piston slidable within said compartment and exposed to said inlet pressure chamber a

A multiple function fuel valve comprising: a valve body having an inlet pressure chamber at one end, a resisting pressure chamber at the other end, and a central piston receiving compartment between said chambers; a piston slidable within said compartment and exposed to said inlet pressure chamber and to said resisting pressure chamber, and having an annular recess between the two ends forming a distribution chamber within said compartment; a first spring between said body and said piston resisting movement of said piston toward said resisting pressure chamber; a second spring between said body and said piston resisting movement of said piston toward said resisting pressure chamber; said first and second springs arranged to produce a lesser spring rate during a first increment portion of the travel of said piston and a greater spring rate during the remainder of the travel of said piston; a plurality of outlet ports through said body in fluid communication with said compartment; an inlet port through said body in fluid communication with said inlet pressure chamber; at least one supply opening through said body in fluid communication with said inlet pressure chamber and said compartment; said distribution chamber alternately out of fluid communication and in simultaneous fluid communication with both said outlet ports and said supply opening, depending on the axial position of said piston; a vent opening through said piston in fluid communication with said inlet pressure chamber and at least one of said outlet ports when said piston is at the limit of axial travel toward said inlet pressure chamber, but out of fluid communication with said at least one outlet port when said piston is remote from said inlet pressure chamber; and a fluid flow restriction in said vent opening.