US3919992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection system
Assignee: Robert Bosch GmbH
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Filing: 1974-09-12
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Granted: 1975-11-18
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Expires: 1994-09-12
Abstract
Abstract A fuel injection system for externally ignited, gas internal combustion engines. The system involves the continuous injection of fuel into an induction tube section of an intake manifold. A measuring member and a randomly activatable throttle valve are arranged in series in the induction tube section upstream from the point of fuel injection. The measuring member is displaced by an operating member against a restoring force in accordance with the amount of air flowing through. In the course of its displacement, the measuring member adjusts a mobile part of a valve which is disposed in the fuel line and meters out a quantity of fuel proportional to the quantity of air, when there is constant pressure difference. The restoring force on the measuring member is produced by a pressure fluid which acts on the operating members at least indirectly. Means are provided for adjusting fuel pressure downstream from the metering valve for influencing pressure of the pressure fluid.
Inventors
- 👤 Konrad Eckert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:12
CPC Classifications
F; F02; F02M; F02M69/00; F02M69/16; F02M69/18; F02M69/22; F02M53/00; F02M53/04; F02M53/06; F02M69/30; F02M69/36; F02M69/42
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
142 words
In a fuel injection system for separately ignited, internal combustion engines involving continuous injection into an induction tube section of an intake manifold, a measuring member and a randomly activatable throttle valve being arranged in series in the induction tube section, the measuring member being displaceable against a restoring force by an operating member according to the amount of air flowing through, a mobile part of a metering valve which is disposed in a fuel line and which, with a constant pressure difference, meters out a quantity of fuel proportional to the amount of air being coupled to the operating member, the restoring force for the measuring member being produced by pressure fluid which acts at least indirectly on the operating member, the improvement comprising means for adjusting fuel pressure downstream from said metering valve for influencing pressure of the pressure fluid.
Claim 2
Dependent Claim
142 words
In a fuel injection system for separately ignited, internal combustion engines involving continuous injection into an induction tube section of an intake manifold, a measuring member and a randomly activatable throttle valve being arranged in series in the induction tube section, the measuring member being displaceable against a restoring force by an operating member according to the amount of air flowing through, a mobile part of a metering valve which is disposed in a fuel line and which, with a constant pressure difference, meters out a quantity of fuel proportional to the amount of air being coupled to the operating member, the restoring force for the measuring member being produced by pressure fluid which acts at least indirectly on the operating member, the improvement comprising means for adjusting fuel pressure downstream from said metering valve for influencing pressure of the pressure fluid.
Claim 3
Dependent Claim
32 words
An improved fuel injection system as claimed in claim 1, wherein said pressure fluid is fuel, the pressure of which is determined by pressure in the system downstream from said metering valve.
Claim 4
Dependent Claim
65 words
An improved fuel injection system as defined in claim 2, including a heatable bi-metallic spring and valve means having spring means; the spring force, which acts in the closing direction, is reduced during the warm-up stage of operation of the engine by means of said heatable bi-metallic spring, said valve means being operatively arranged to vary pressure in the system upstream from said metering valve.
Claim 5
Dependent Claim
29 words
An improved fuel injection system as defined in claim 3, including an injection valve disposed immediately downstream from said throttle valve for injecting fuel into said induction tube section.
Claim 6
Dependent Claim
26 words
An improved fuel injection system as defined in claim 4, including electrical heating means disposed in the vicinity of said injection valve for heating the fuel.
Claim 7
Dependent Claim
43 words
An improved fuel injection system as defined in claim 4, wherein said spring means includes a first spring holding a valve needle of the injection valve in the closing position acts against a second spring which is also part of said spring means.
Claim 8
Dependent Claim
33 words
An improved fuel injection system as defined in claim 6, including an adjustable piston and wherein initial stressing of said second spring is varied by said heatable bi-metallic spring via said adjusting piston.
Claim 9
Dependent Claim
27 words
An improved fuel injection system as defined in claim 7, including two stops, and wherein said adjusting piston is displaceable between two stops defining its end positions.
Claim 10
Dependent Claim
44 words
An improved fuel injection system as defined in claim 8, including a duct connected between said induction tube section and a region adjacent said adjusting piston for introducing leaking fuel from the adjusting piston into said induction tube section downstream of said throttle valve.
Claim 11
Dependent Claim
24 words
An improved fuel injection system as defined in claim 4, wherein said valve means and said spring means are arranged within said injection valve.
Claim 12
Dependent Claim
30 words
A fuel injection system as claimed in claim 10, wherein said injection valve is operatively arranged to act as a valve for varying fuel pressure downstream from said metering valve.
Claim 13
Dependent Claim
55 words
A fuel injection system as claimed in claim 10, including a closing spring, and wherein said valve for varying fuel pressure downstream from said metering valve comprises a flat seat valve with a diaphragm as its displaceable valve part, said diaphragm being positioned to be acted on by said closing spring in the closing direction.
Claim 14
Dependent Claim
27 words
A fuel injection system as claimed in claim 12, wherein the force of said closing spring on said diaphragm is reduced by action of said bi-metallic spring.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |