US4724812A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for controlling the air-fuel ratio for an internal combustion engine
Assignee: Aisin Corp
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Filing: 1987-03-20
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Granted: 1988-02-16
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Expires: 2007-03-20
Abstract
Abstract An apparatus for controlling the air-fuel ratio for an internal combustion engine and which includes a flame sensor provided in the vicinity of a spark plug within an engine combustion chamber, an air induction passage for bypassing a throttle valve of a carburetor, an electromagnetic valve disposed in the air induction passage to control an amount of air flowing through the air induction passage, and an electronic control unit actuating the electromagnetic valve by means of input electric signals from the flame sensor and including a control MAP based on a mutual relation between an air-fuel ratio and a time of firing.
Inventors
- 👤 Motonobu Akagi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:14
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/02; F02D41/14; F02D41/1438; F02D41/1444; F02D41/1451; F02D35/00; F02D35/0015; F02D35/0023; F02D35/003; F02D35/02; F02D35/021
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
163 words
An apparatus for controlling the air-fuel ratio for an internal combustion engine having a spark plug located therein and utilizing a carburetor with a throttle valve, comprising: a flame sensor provided in the vicinity of said spark plug for detecting firing timing; an air induction bypass for bypassing said throttle valve of said carburetor; electromagnetic valve means disposed in said air induction bypass passage for controlling an amount of air flowing through said air induction bypass passage; and electronic control device means in communication with said electromagnetic valve for actuating said electromagnetic valve by means of input electric signals from said flame sensor, wherein said electronic control device means further comprises a control MAP based on a mutual relation between an air-fuel ratio, spark timing and firing timing, said electronic control device means controlling via said control MAP a degree of opening of said electromagnetic valve means under a condition of a controlled spark timing so that a desired air-fuel ratio is maintained.
Claim 2
Independent Claim
163 words
An apparatus for controlling the air-fuel ratio for an internal combustion engine having a spark plug located therein and utilizing a carburetor with a throttle valve, comprising: a flame sensor provided in the vicinity of said spark plug for detecting firing timing; an air induction bypass for bypassing said throttle valve of said carburetor; electromagnetic valve means disposed in said air induction bypass passage for controlling an amount of air flowing through said air induction bypass passage; and electronic control device means in communication with said electromagnetic valve for actuating said electromagnetic valve by means of input electric signals from said flame sensor, wherein said electronic control device means further comprises a control MAP based on a mutual relation between an air-fuel ratio, spark timing and firing timing, said electronic control device means controlling via said control MAP a degree of opening of said electromagnetic valve means under a condition of a controlled spark timing so that a desired air-fuel ratio is maintained.
Claim 3
Dependent Claim
29 words
An apparatus for controlling the air-fuel ratio for an internal combustion engine as set forth in claim 1 wherein said flame sensor further comprises a plurality of platinum wires.
Claim 4
Dependent Claim
28 words
An apparatus for controlling the air-fuel ratio for an internal combustion engine as set forth in claim 1 wherein said control MAP is corrected by engine driving conditions.
Claim 5
Dependent Claim
38 words
An apparatus for controlling the air-fuel ratio for an internal combustion engine as set forth in claim 3 wherein said engine driving conditions further comprise engine rotational speed, cooling water temperature, intake manifold vacuum, and gasoline octane rating.
Claim 6
Dependent Claim
29 words
An apparatus for controlling the air-fuel ratio for an internal combustion engine as set forth in claim 1 wherein said electromagnetic valve further comprises an electromagnetically operable linear motor.
References Cited (Backward Citations)
US4285319A
Cited
US4377140A
Cited
US4462368A
Cited
US4465046A
Cited
US4489596A
Cited
US4535740A
Cited
US4561394A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-15 | 1991-08-17 | 1992-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-15 | 1995-08-17 | 1996-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-15 | 1999-08-17 | 2000-02-16 | $7700.00 | Window Closed / Lapsed |