초록 ▼

A normally-open, solenoid-controlled valve rapidly controls the flow of liquid between a high pressure supply and a relatively lower pressure drain. The valve includes a stationary valve-seat spindle and a cylindrical valve sleeve encircling and slidable along part of the valve-seat spindle. The val

A normally-open, solenoid-controlled valve rapidly controls the flow of liquid between a high pressure supply and a relatively lower pressure drain. The valve includes a stationary valve-seat spindle and a cylindrical valve sleeve encircling and slidable along part of the valve-seat spindle. The valve-seat spindle is provided with an annular control edge and the valve sleeve includes a frustoconical pressure-responsive contact surface which is moved into and out of valve-closing contact with the control edge by means of axial reciprocation of the valve sleeve between valve-closed and valve-open positions. The valve-seat spindle includes a flow passage therein which is in continuous fluid communication with a high pressure fluid inlet in a valve housing and which extends to and discharges into a plenum region formed between the spindle and the sleeve adjacent to the control edge and relatively toward that part of the seat spindle along which the valve sleeve slides. When energization of the solenoid is discontinued, the high pressure liquid in the plenum acts axially on the valve sleeve, and particularly the pressure-responsive contact surface, to rapidly open the valve. The response rate and simplicity of the valve are enhanced by the absence of a biasing spring. The valve is suited for use as a bypass valve in integral combination with a high pressure fuel injector nozzle of the pressure-responsive type.

대표청구항 ▼

A solenoid-valve controlled fuel injector assembly comprising, in combination: an injector nozzle including a nozzle body, an injector valve in the nozzle body operative between closed and open positions, means biasing said injector valve to said closed position, and a main fuel passage extending in

A solenoid-valve controlled fuel injector assembly comprising, in combination: an injector nozzle including a nozzle body, an injector valve in the nozzle body operative between closed and open positions, means biasing said injector valve to said closed position, and a main fuel passage extending in said nozzle body from a first port to said injector valve, said biasing means being overcome and said injector valve being opened when a predetermined fuel pressure threshold in said nozzle fuel passage is exceeded; said nozzle body including a bypass fuel passage extending from said main fuel passage to a second port; and a rapidly-responding, normally-open solenoid-controlled bypass valve assembly including a bypass valve housing integrally connected to said nozzle body and having a drain port, a stationary valve-seat spindle positioned in said bypass valve housing, said valve-seat spindle having a first axial portion of one diameter and a second axial portion of greater diameter than said first portion, an annular control edge of greater diameter than said first portion being formed on said seat spindle second portion, a valve sleeve closely encircling said first portion of said seat spindle in axial sliding relation therewith, said valve sleeve being slidably displaceable between a closed position having a surface thereof in sealing contact with said seat control edge and an open position in which said control edge contacting surface is spaced from said seat control edge axially in the direction of said seat spindle first portion, said valve-seat spindle including a bypass fuel passage therein, said seat spindle bypass fuel passage being in continuous fluid communication with said nozzle body bypass fuel passage via said second port and having a discharge to a plenum region formed between said spindle and said sleeve and radially inward of said control edge, said valve sleeve including a pressure reaction surface radially inward of said valve-sleeve spindle control edge and in continuous communication with said plenum, an armature operatively connected to said valve sleeve, and electromagnetic means responsive to an electrical current for displacing said armature to move said valve sleeve from said open position to said closed position to allow fuel pressure in said main fuel passage to exceed said injector valve threshold, and wherein the pressure of said fuel in said plenum acting axially on said valve sleeve reaction surface rapidly opens said bypass valve when said electrical current terminates and allows flow of said fuel by said bypass valve to said drain port thereby to decrease fuel pressure in said main fuel passage to less than said injector valve threshold.