US3777726A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection apparatus
Assignee: Robert Bosch GmbH
•
Filing: 1971-10-28
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Granted: 1973-12-11
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Expires: 1991-10-28
Abstract
Abstract In a fuel injection apparatus which delivers metered fuel to fuel injection valves, there is provided, downstream of each differential pressure valve which ensures a constant pressure drop across each fuel metering valve and upstream of the associated fuel injection valve, a chopper valve which, in the low rpm range effects an intermittent fuel injection into the intake tube of the internal combustion engine to prevent uncombusted gas mixture from entering the exhaust system in said rpm range.
Inventors
- 👤 H Knapp
- 👤 G Jaggle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:23
CPC Classifications
F; F02; F02M; F02M69/00; F02M69/14; F02M69/145; F02M69/147; F02M69/16; F02M69/26; F02M69/46; F02M69/50
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
170 words
In a fuel injectioN apparatus associated with a multicylinder internal combustion engine, said apparatus being of the type that includes (a) fuel metering valves equalling the number of cylinders in said engine, (b) means for simultaneously controlling said fuel metering valves, (c) a separate differential pressure valve joining each fuel metering valve downstream thereof for ensuring a constant pressure drop across each fuel metering valve independently from the flow passage section thereof and (d) a separate fuel injection valve downstream of each differential pressure valve for receiving metered fuel therefrom, the improvement comprising: A. chopper valve means disposed between each said differential pressure valve and its associated fuel injection valve to effect an intermittent delivery of accumulated fuel downstream from each differential pressure valve to its associated fuel injection valve and B. rpm-responsive means operatively connected to said chopper valve means for rendering the latter effective at lower rpm''s to provide for intermittent delivery of fuel and rendering it ineffective at higher rpm''s to provide for continuous delivery of fuel.
Claim 2
Dependent Claim
170 words
In a fuel injectioN apparatus associated with a multicylinder internal combustion engine, said apparatus being of the type that includes (a) fuel metering valves equalling the number of cylinders in said engine, (b) means for simultaneously controlling said fuel metering valves, (c) a separate differential pressure valve joining each fuel metering valve downstream thereof for ensuring a constant pressure drop across each fuel metering valve independently from the flow passage section thereof and (d) a separate fuel injection valve downstream of each differential pressure valve for receiving metered fuel therefrom, the improvement comprising: A. chopper valve means disposed between each said differential pressure valve and its associated fuel injection valve to effect an intermittent delivery of accumulated fuel downstream from each differential pressure valve to its associated fuel injection valve and B. rpm-responsive means operatively connected to said chopper valve means for rendering the latter effective at lower rpm''s to provide for intermittent delivery of fuel and rendering it ineffective at higher rpm''s to provide for continuous delivery of fuel.
Claim 3
Dependent Claim
42 words
An improvement as defined in claim 1, including A. a separate accumulator chamber in communication with each differential pressure valve and disposed downstream thereof and B. an accumulator member movably disposed in each accumulator chamber to determine the volume of the latter.
Claim 4
Dependent Claim
63 words
An improvement as defined in claim 2, wherein said accumulator member is formed as an accumulator piston slidable in said accumulator chamber, said improvement further includes A. means exerting a return force on said accumulator piston against the force generated by the pressure of fuel in said accumulator chamber and B. means for rotating said accumulator piston with the rpm of said engine.
Claim 5
Dependent Claim
46 words
An improvement as defined in claim 3, wherein said means for rotating said accumulator piston includes A. a gearing and B. a soft leaf spring for drivingly coupling said gearing to said accumulator piston, said soft leaf spring also constitutes said means exerting a return force.
Claim 6
Dependent Claim
46 words
An improvement as defined in claim 3, including means for admitting fuel under pressure to said accumulator piston for opposing the force of the fuel in said accumulator chamber; said last-named means, together with the associated fuel under pressure constitutes said means exerting a return force.
Claim 7
Dependent Claim
57 words
An improvement as defined in claim 3, wherein said accumulator piston has on its lateral face an axially parallel groove in communication with said accumulator chamber, said groove, during rotation of said accumulator piston, is adapted to be in and out of registry with an outlet port connecting said accumulator chamber with the associated fuel injection valve.
Claim 8
Dependent Claim
62 words
An improvement as defined in claim 2, wherein said accumulator member is constituted by a membrane, said improvement further includes A. an electromagnetic valve disposed downstream of said accumulator chamber and upstream of the associated fuel injection valve, said electromagnetic valve constitutes said chopper valve means and B. a monostable multi-vibrator operatively connected to said electromagnetic valve and constituting said rpm-responsive means.
Claim 9
Dependent Claim
27 words
An improvement as defined in claim 7, including means for flipping said monostable multi-vibrator from its stable condition into its unstable condition synchronously with the engine rpm.
Claim 10
Dependent Claim
41 words
An improvement as defined in claim 7, including A. contacts incorporated in the ignition distributor of the engine, said contacts being connected with said monostable multi-vibrator and B. means for periodically opening and closing said contacts to trigger said monostable multi-vibrator.
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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) | 1976-12-10 | 1977-06-11 | 1977-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-10 | 1981-06-11 | 1981-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-10 | 1985-06-11 | 1985-12-11 | $7700.00 | Window Closed / Lapsed |