Patent US3875742A successfully refreshed from Google Patents.
Patent EP0195736B1 successfully refreshed from Google Patents.
EP0195736B1
Expired / Lapsed
EP
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Accumulator injector
Assignee: Stanadyne LLC
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Filing: 1986-02-20
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Granted: 1989-05-17
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Expires: 2006-02-20
Abstract
No abstract record available.
Inventors
- 👤 William W. Kelly
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 11:12
CPC Classifications
F; F02; F02M; F02M59/00; F02M59/02; F02M59/10; F02M59/105; F02M45/00; F02M45/02; F02M45/04; F02M47/00; F02M47/02; F02M57/00; F02M57/02; F02M57/022; F02M57/025
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
385 words
Accumulator fuel injector for injecting a pressurized charge of fuel into a cylinder of an internal combustion engine comprising: an injector body (12) having a fuel inlet (14) for receiving pressurized fuel at a supply pressure, an injection valve opening (72) for discharging accumulated pressurized fuel and a valve seat (74) surrounding the injection valve opening (72); an elongated valve member (70) mounted in the injector body (12) and adapted for engagement with the valve seat (74) to close the valve opening (72) and for momentary axial displacement to open the valve opening (72); an accumulator pressure chamber (86) communicating with said fuel inlet (14) and with said valve opening (72) for discharging a pressurized charge of fuel upon opening said valve opening (72), said valve member (70) being urged to open the valve opening (72) by means of a supply pressure responsive pressure exerted in said accumulator chamber (86); a control pressure chamber (58; 114) communicating with said fuel inlet (14), said valve member (70) being urged to close the valve opening (72) by means of a supply pressure responsive pressure exerted in said control chamber (58; 114); a check valve (78) between the control pressure chamber (58; 114) and the accumulator pressure chamber (86) and operated by the pressure difference in the control pressure chamber (58; 114) and the accumulator pressure chamber (86), said check valve (78) being closed when said valve opening (72) is open; and pressure release means controllably actuatable to effect a decrease in pressure in said control chamber (58, 114); characterized in that a shuttle bore (88) is disposed in said injector body (12), one end of said shuttle bore (88) being connected with the control pressure chamber (58; 114) and the other end of the shuttle bore (88) being connected with the accumulator pressure chamber (86), and that a shuttle piston (90) is axially displaceable in said shuttle bore (88) responsive to a pressure drop in the control pressure chamber (58, 114) and the simultaneous opening of the valve opening (72) in a direction towards the end of the shuttle bore (88) which is connected with the control pressure chamber (58; 114), thereby increasing the pressure in the control pressure chamber (58; 114), while decreasing the pressure in the accumulator pressure chamber (86) to limit initial fuel injection.
Claim 2
Dependent Claim
385 words
Accumulator fuel injector for injecting a pressurized charge of fuel into a cylinder of an internal combustion engine comprising: an injector body (12) having a fuel inlet (14) for receiving pressurized fuel at a supply pressure, an injection valve opening (72) for discharging accumulated pressurized fuel and a valve seat (74) surrounding the injection valve opening (72); an elongated valve member (70) mounted in the injector body (12) and adapted for engagement with the valve seat (74) to close the valve opening (72) and for momentary axial displacement to open the valve opening (72); an accumulator pressure chamber (86) communicating with said fuel inlet (14) and with said valve opening (72) for discharging a pressurized charge of fuel upon opening said valve opening (72), said valve member (70) being urged to open the valve opening (72) by means of a supply pressure responsive pressure exerted in said accumulator chamber (86); a control pressure chamber (58; 114) communicating with said fuel inlet (14), said valve member (70) being urged to close the valve opening (72) by means of a supply pressure responsive pressure exerted in said control chamber (58; 114); a check valve (78) between the control pressure chamber (58; 114) and the accumulator pressure chamber (86) and operated by the pressure difference in the control pressure chamber (58; 114) and the accumulator pressure chamber (86), said check valve (78) being closed when said valve opening (72) is open; and pressure release means controllably actuatable to effect a decrease in pressure in said control chamber (58, 114); characterized in that a shuttle bore (88) is disposed in said injector body (12), one end of said shuttle bore (88) being connected with the control pressure chamber (58; 114) and the other end of the shuttle bore (88) being connected with the accumulator pressure chamber (86), and that a shuttle piston (90) is axially displaceable in said shuttle bore (88) responsive to a pressure drop in the control pressure chamber (58, 114) and the simultaneous opening of the valve opening (72) in a direction towards the end of the shuttle bore (88) which is connected with the control pressure chamber (58; 114), thereby increasing the pressure in the control pressure chamber (58; 114), while decreasing the pressure in the accumulator pressure chamber (86) to limit initial fuel injection.
Claim 3
Dependent Claim
59 words
Accumulator fuel injector according to claim 1, characterized in that said shuttle bore (88) forms a seat (89) and the shuttle piston (90) has a tapered end portion which is seatable against said seat (89) to form a trigger pressure chamber (91), said shuttle piston (90) being biased by a spring (100) to seat against said bore seat (89).
Claim 4
Dependent Claim
62 words
Accumulator fuel injector according to claim 2, characterized in that said shuttle piston (90) has an axial bleed bore (98) and a restricted bleed orifice (96) communicating with said trigger chamber (91), said orifice (96) being dimensioned to permit displacement of the shuttle piston (90) from the seat (89) in the event of a rapid pressure decrease in the control chamber (58).
Claim 5
Dependent Claim
44 words
Accumulator fuel injector according to claim 1, characterized in that said displacement of the shuttle piston (90) causes a momentary reseating of the valve member (70) to produce a pilot injection prior to a primary injection of pressurized fuel through the valve opening (72).
Claim 6
Dependent Claim
36 words
Accumulator fuel injector according to claim 4, characterized in that at relatively low supply pressures a pilot injection and a primary injection are produced while at relatively higher supply pressures only a primary injection is produced.
Claim 7
Dependent Claim
35 words
Accumulator fuel injector according to claim 1, characterized in that said pressure release means comprises a solenoid actuated control valve assembly for controllably effecting a rapid decrease in fuel pressure in said control chamber (58).
Claim 8
Dependent Claim
79 words
Accumulator fuel injector according to claim 3, characterized by comprising an intensifier chamber (24) and a supply passage (16, 18, 20, 22), said intensifier chamber (24) communicating via said supply passage (16, 18, 20, 22) with the fuel inlet (14), and an intensifier piston (50, 52) received in said intensifier chamber (26), the pressure in said control chamber (58) being intensified by said intensifier piston (50, 52) driven by a supply pressure responsive pressure in said intensifier chamber (24).
Claim 9
Dependent Claim
58 words
Accumulator fuel injector according to claim 7, characterized in that said supply passage (16, 18, 20, 22) has a restricted control orifice (22), the control orifice (22) and shuttle piston bleed orifice (96) being dimensioned to provide a momentary reseating of the valve member (70) in the event of a rapid pressure decrease in the control chamber (58).
Claim 10
Dependent Claim
39 words
Accumulator fuel injector according to claim 7, characterized in that the injector is chargeable so that the ratio of the pressure in the control chamber (58) to the fuel inlet pressure is on the order of 2 to 1.
References Cited (Backward Citations)
US2558148A
Cited
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