US3710769A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection system for internal combustion engines
Assignee: Robert Bosch GmbH
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Filing: 1971-01-19
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Granted: 1973-01-16
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Expires: 1991-01-19
Abstract
Abstract In a fuel injection system, in order to prevent an intake air sensor to transmit those forces to a fuel control valve which are generated upon sudden thrusts of air in the engine intake tube, there is provided a valved passage which connects intake tube portions upstream and downstream of the intake air sensor and which opens in response to a predetermined pressure differential prevailing across the intake air sensor.
Inventors
- 👤 H Knapp
- 👤 R Schwartz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:06
CPC Classifications
F; F02; F02M; F02M69/00; F02M69/46; F02M69/48; F02M69/30; F02M69/32
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
245 words
In a fuel injection system for an internal combustion engine having an inlet conduit for the intake of air, said system being of the known type that includes (a) an arbitrarily operable throttle valve disposed in said inlet conduit to vary the flow rate of intake air, (b) an air sensor disposed in said inlet conduit and displaceable against the force of a constant resetting means to an extent proportional to the flow rate of intake air, said air sensor is displaceable by a pressure differential formed of the difference between the pressures prevailing in said inlet conduit upstream and downstream of said air sensor, (c) a fuel metering valve, the position of which is dependent upon the extent of displacement of said air sensor and (d) means operatively connecting said air sensor to said fuel metering valve, the improvement comprising A. passage means interconnecting a location in said inlet conduit upstream of said air sensor with a location in said inlet conduit downstream of said air sensor, B. valve means disposed in said passage means to control the flow passage section thereof and C. bias means for urging said valve means into a closed position obstructing said passage means; the force of said bias means being so designed that said valve means being openable against said bias means by said pressure difference when reaching a predetermined value over the value necessary to displace said air sensor against the force of said constant resetting means.
Claim 2
Dependent Claim
245 words
In a fuel injection system for an internal combustion engine having an inlet conduit for the intake of air, said system being of the known type that includes (a) an arbitrarily operable throttle valve disposed in said inlet conduit to vary the flow rate of intake air, (b) an air sensor disposed in said inlet conduit and displaceable against the force of a constant resetting means to an extent proportional to the flow rate of intake air, said air sensor is displaceable by a pressure differential formed of the difference between the pressures prevailing in said inlet conduit upstream and downstream of said air sensor, (c) a fuel metering valve, the position of which is dependent upon the extent of displacement of said air sensor and (d) means operatively connecting said air sensor to said fuel metering valve, the improvement comprising A. passage means interconnecting a location in said inlet conduit upstream of said air sensor with a location in said inlet conduit downstream of said air sensor, B. valve means disposed in said passage means to control the flow passage section thereof and C. bias means for urging said valve means into a closed position obstructing said passage means; the force of said bias means being so designed that said valve means being openable against said bias means by said pressure difference when reaching a predetermined value over the value necessary to displace said air sensor against the force of said constant resetting means.
Claim 3
Dependent Claim
22 words
An improvement as defined in claim 1, including means to vary the force of said bias means as a function of temperature.
Claim 4
Dependent Claim
72 words
An improvement as defined in claim 1, including A. a plate constituting said air sensor and said valve means, B. a lever forming part of said means operatively connecting said air sensor to said fuel metering valve, C. a pivot pin eccentrically and swingably securing said plate to said lever and D. a spring, constituting said bias means, engaging said lever and said plate to urge said plate into said closed position.
Claim 5
Dependent Claim
50 words
An improvement as defined in claim 1, including A. a bypass extending externally of said air sensor and constituting said passage means, B. a check valve controlling said bypass and constituting said valve means, and C. a spring, constituting said bias means, urging said check valve into said closed position.
Claim 6
Dependent Claim
65 words
An improvement as defined in claim 1, including A. an orifice provided in said air sensor and constituting said passage means, B. a check valve mounted on said air sensor for controlling said orifice, said check valve constitutes said valve means and C. a spring supported on said air sensor for urging said check valve into said closed position, said spring constitutes said bias means.
Claim 7
Dependent Claim
90 words
An improvement as defined in claim 1, including A. a plate constituting said air sensor and said valve means, B. a guide rod displaceable axially in said inlet conduit parallel to the direction of air flow therein, said guide rod forms part of said means operatively connecting said air sensor to said fuel metering valve, C. means for axially slidably securing said plate on said guide rod and D. a spring supported on said guide rod for urging said plate into said closed position, said spring constitutes said bias means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-16 | 1976-07-17 | 1977-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-16 | 1980-07-17 | 1981-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-16 | 1984-07-17 | 1985-01-16 | $7700.00 | Window Closed / Lapsed |