US4784103A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for controlling fuel injection for automotive engines
Assignee: Subaru Corp
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Filing: 1987-07-10
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Granted: 1988-11-15
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Expires: 2007-07-10
Abstract
Abstract A basic fuel injection time is obtained based on engine speed and intake-air pressure in an intake passage of an engine downstream of a throttle valve of the engine. The basic fuel injection time is corrected by a correcting value based on a constant for a fuel injector and capacity of a chamber formed in an intake passage and on variation in intake-air pressure at every one rotation of a crankshaft of the engine when the idling state of the engine or throttle rapid closing are detected.
Inventors
- 👤 Hiroshi Ohishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:16
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/30; F02D41/32; F02D41/02; F02D41/04; F02D41/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
124 words
A method for controlling fuel injection for an automotive engine comprising: determining constants of an injector for the fuel injection and of a capacity of a chamber formed in an intake passage of the engine; detecting engine speed and intake-air pressure in the intake passage downstream of a throttle valve of the engine; calculating a basic fuel injection time based on the detected engine speed and intake-air pressure; said detecting intake-air pressure includes detecting the intake-air pressure at every one rotation of a crankshaft of said engine; calculating the difference between the detected intake-air pressures at every one rotation of the crankshaft; correcting the basic fuel injection time by adding thereto a correcting value which is the product of said constants and said difference.
Claim 2
Independent Claim
124 words
A method for controlling fuel injection for an automotive engine comprising: determining constants of an injector for the fuel injection and of a capacity of a chamber formed in an intake passage of the engine; detecting engine speed and intake-air pressure in the intake passage downstream of a throttle valve of the engine; calculating a basic fuel injection time based on the detected engine speed and intake-air pressure; said detecting intake-air pressure includes detecting the intake-air pressure at every one rotation of a crankshaft of said engine; calculating the difference between the detected intake-air pressures at every one rotation of the crankshaft; correcting the basic fuel injection time by adding thereto a correcting value which is the product of said constants and said difference.
Claim 3
Dependent Claim
43 words
The method according to claim 1 wherein said method comprising, detecting idling state of the engine or throttle rapid closing based on throttle position; correcting the basic fuel injection time when the idling state of the engine or throttle rapid closing is detected.
Claim 4
Dependent Claim
17 words
The method according to claim 1, wherein said one rotation equals 360° of rotation of the crankshaft.
Claim 5
Independent Claim
120 words
A method for controlling fuel injection for an automotive engine having an intake passage with a throttle valve disposed in the intake passage comprising: determining a constant of an injector for the fuel injection; detecting engine speed and intake-air pressure in the intake passage downstream of the throttle valve; calculating a basic fuel injection time based on the detected engine speed and intake-air pressure; said detecting intake-air pressure includes detecting the intake-air pressure at every one rotation of a crankshaft of said engine; calculating the difference between the detected intake-air pressures at every one rotation of the crankshaft; correcting the basic fuel injection time by adding thereto a correcting value which is the product of said constant and said difference.
Claim 6
Independent Claim
120 words
A method for controlling fuel injection for an automotive engine having an intake passage with a throttle valve disposed in the intake passage comprising: determining a constant of an injector for the fuel injection; detecting engine speed and intake-air pressure in the intake passage downstream of the throttle valve; calculating a basic fuel injection time based on the detected engine speed and intake-air pressure; said detecting intake-air pressure includes detecting the intake-air pressure at every one rotation of a crankshaft of said engine; calculating the difference between the detected intake-air pressures at every one rotation of the crankshaft; correcting the basic fuel injection time by adding thereto a correcting value which is the product of said constant and said difference.
Claim 7
Dependent Claim
17 words
The method according to claim 4, wherein said one rotation equals 360° of rotation of the crankshaft.
Claim 8
Independent Claim
137 words
An apparatus for controlling fuel injection by a fuel injector having a constant factor of fuel injection time for an automotive engine having an intake passage with a throttle valve disposed in the intake passage comprising: means for detecting engine speed and intake-air pressure in the intake passage downstream of the throttle valve; means for calculating a basic fuel injection time based on the detected engine speed and intake-air pressure; said detecting intake-air pressure includes detecting the intake-air pressure at every one rotation of a crankshaft of said engine; means for calculating the difference between the detected intake-air pressures at a rotation of the crankshaft and one rotation of the crankshaft prior thereto; means for correcting the basic fuel injection time by adding thereto a correcting value which is the product of said constant and said difference.
Claim 9
Independent Claim
137 words
An apparatus for controlling fuel injection by a fuel injector having a constant factor of fuel injection time for an automotive engine having an intake passage with a throttle valve disposed in the intake passage comprising: means for detecting engine speed and intake-air pressure in the intake passage downstream of the throttle valve; means for calculating a basic fuel injection time based on the detected engine speed and intake-air pressure; said detecting intake-air pressure includes detecting the intake-air pressure at every one rotation of a crankshaft of said engine; means for calculating the difference between the detected intake-air pressures at a rotation of the crankshaft and one rotation of the crankshaft prior thereto; means for correcting the basic fuel injection time by adding thereto a correcting value which is the product of said constant and said difference.
Claim 10
Dependent Claim
17 words
The apparatus according to claim 6, wherein said one rotation equals 360° of rotation of the crankshaft.
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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) | 1991-11-15 | 1992-05-16 | 1992-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-15 | 1996-05-16 | 1996-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-15 | 2000-05-16 | 2000-11-15 | $7700.00 | Window Closed / Lapsed |