Patent US3689205A successfully refreshed from Google Patents.
US3689205A
Expired / Lapsed
US
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Pump-and-nozzle assembly for injecting fuel into internal combustion engines
Assignee: Robert Bosch GmbH
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Filing: 1971-02-19
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Granted: 1972-09-05
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Expires: 1991-02-19
Abstract
Abstract A pump - and - nozzle assembly for injecting fuel into internal combustion engines includes a servo piston which operates a smaller pump piston in response to pressurized fuel periodically admitted to and removed from said servo piston by virtue of a respective first and second position of a solenoid valve also forming part of said assembly. In said first position the fuel injection is triggered, while in said second position the return stroke of the servo piston is initiated and the injection is rapidly terminated. For the latter purpose a continuous communication exists between the work chamber of the pump piston and the injection nozzle.
Inventors
- 👤 Heinz Links
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:03
CPC Classifications
F; F02; F02M; F02M57/00; F02M57/02; F02M57/022; F02M57/025; F02M59/00; F02M59/20; F02M59/34; F02M2700/00; F02M2700/13; F02M2700/1317; F02M2700/1358
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
221 words
In a pump - and - nozzle assembly for injecting fuel into internal combustion engines, wherein said assembly is of the known type that includes (a) a reciprocating pump piston associated with a pump work chamber, (b) a servo piston driving said pump piston and having a diameter larger than that of said pump piston, (c) means for supplying fuel under servo pressure for driving said servo piston, (d) means for supplying fuel under said servo pressure to the pump work chamber of said pump piston, (e) a solenoid valve actuated synchronously with the operation of said engine and adapted to assume a first position in which it directs said fuel to said servo piston causing a forward stroke thereof, thereby triggering the start of fuel injection into said engine and a second position in which it causes said servo piston to be relieved of the servo pressure of said fuel to permit its return stroke to begin and (f) a nozzle through which fuel is injected into said engine, the improvement comprising, A. means for terminating said fuel injection simultaneously with the start of said return stroke of said servo piston upon assumption of said second position by said solenoid valve and B. means providing a continuous communication between said pump work chamber of said pump piston and said nozzle.
Claim 2
Dependent Claim
221 words
In a pump - and - nozzle assembly for injecting fuel into internal combustion engines, wherein said assembly is of the known type that includes (a) a reciprocating pump piston associated with a pump work chamber, (b) a servo piston driving said pump piston and having a diameter larger than that of said pump piston, (c) means for supplying fuel under servo pressure for driving said servo piston, (d) means for supplying fuel under said servo pressure to the pump work chamber of said pump piston, (e) a solenoid valve actuated synchronously with the operation of said engine and adapted to assume a first position in which it directs said fuel to said servo piston causing a forward stroke thereof, thereby triggering the start of fuel injection into said engine and a second position in which it causes said servo piston to be relieved of the servo pressure of said fuel to permit its return stroke to begin and (f) a nozzle through which fuel is injected into said engine, the improvement comprising, A. means for terminating said fuel injection simultaneously with the start of said return stroke of said servo piston upon assumption of said second position by said solenoid valve and B. means providing a continuous communication between said pump work chamber of said pump piston and said nozzle.
Claim 3
Dependent Claim
48 words
An improvement as defined in claim 1, wherein said means defined in (d) includes a fuel supply channel; said improvement comprises a throttle means to extend the period of fuel supply to said pump work chamber until the start of the fuel injection of a successive work cycle.
Claim 4
Dependent Claim
47 words
An improvement as defined in claim 2, including a fuel supply valve formed of a check valve disposed between said throttle means and said pump work chamber, said check valve includes means for biasing the same to a fuel charging pressure which is below said servo pressure.
Claim 5
Dependent Claim
25 words
An improvement as defined in claim 3, including a restriction at said check valve to additionally throttle the fuel supply to said pump work chamber.
Claim 6
Dependent Claim
44 words
An improvement as defined in claim 1, wherein said solenoid valve is formed of a pressure-equalized, 3/2-way valve including a displaceable sphere as a movable valve member and an electromagnet including a sole control winding and a movable armature operatively connected to said sphere.
References Cited (Backward Citations)
US2537748A
Cited
US2598528A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-05 | 1976-03-06 | 1976-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-05 | 1980-03-06 | 1980-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-05 | 1984-03-06 | 1984-09-05 | $7700.00 | Window Closed / Lapsed |