US4571683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Learning control system of air-fuel ratio in electronic control engine
Assignee: Toyota Motor Corp
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Filing: 1982-07-29
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Granted: 1986-02-18
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Expires: 2002-07-29
Abstract
Abstract This system computes final fuel injection amount TAU on the basis of the following formula; TAU=A×TP+B+J where A : a first learning term B : a second learning term TP : basic fuel injection amount J : correction amount Learning control is effected by correcting the second learning term B during idling periods and by correcting the first learning term A when an engine has larger than a predetermined load.
Inventors
- 👤 Nobuyuki Kobayashi
- 👤 Toshiaki Isobe
- 👤 Nobuhisa Ohkawa
- 👤 Takahide Kuma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:14
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/24; F02D41/2406; F02D41/2425; F02D41/2429; F02D41/2451; F02D41/2454; F02D41/2441; F02D41/2445; F02D41/2477; F02D41/248
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
139 words
A system for learning control of the air-fuel ratio in an electronically controlled engine comprising: means for generating an indication of engine load; means for generating a ratio signal indicative of air-fuel ratio by monitoring exhaust gases of said engine; and processing means for: (1) determining a basic fuel injection amount, TP, as a predetermined function of engine load, (2) determining a final fuel injection amount, TAU, in accordance with TAU=AxTP+B+J wherein A is a first learning term, B is a second learning term and J is a correction amount, (3) correcting said first learning term A in response to said ratio signal when said engine has a load larger than a predetermined value, and (4) correcting said second learning term B in response to said ratio signal when said engine has a load smaller than said predetermined value.
Claim 2
Independent Claim
139 words
A system for learning control of the air-fuel ratio in an electronically controlled engine comprising: means for generating an indication of engine load; means for generating a ratio signal indicative of air-fuel ratio by monitoring exhaust gases of said engine; and processing means for: (1) determining a basic fuel injection amount, TP, as a predetermined function of engine load, (2) determining a final fuel injection amount, TAU, in accordance with TAU=AxTP+B+J wherein A is a first learning term, B is a second learning term and J is a correction amount, (3) correcting said first learning term A in response to said ratio signal when said engine has a load larger than a predetermined value, and (4) correcting said second learning term B in response to said ratio signal when said engine has a load smaller than said predetermined value.
Claim 3
Dependent Claim
31 words
A learning control system as defined in claim 1, wherein said load indication generating means includes means for detecting intake pipe pressure, a predetermined intake pipe pressure being said predetermined value.
Claim 4
Dependent Claim
33 words
A learning control system as defined in claim 1, wherein said load indication generating means includes means for detecting intake air flow rate, a predetermined intake air flow rate being said predetermined value.
Claim 5
Dependent Claim
36 words
A learning control system as defined in claim 1, wherein said load indication generating means includes means for detecting the opening of a throttle valve, a predetermined opening of the throttle valve being said predetermined value.
Claim 6
Dependent Claim
39 words
A learning control system as defined in claim 1, 3, 4 or 2 further comprising means for detecting engine running conditions other than load, said correction amount J being a function of said engine running conditions other than load.
Claim 7
Dependent Claim
29 words
A learning control system as defined in claim 5, wherein said engine condition detecting means includes means for detecting at least one of engine temperature and intake air temperature.
Claim 8
Independent Claim
175 words
A system for learning control of the air-fuel ratio in an electronically controlled engine comprising: means for generating an indication of engine load; means for generating a ratio signal indicative of air-fuel ratio by monitoring exhaust gases of said engine; and processing means for: (1) determining a basic fuel injection amount, TP, as a predetermined function of engine load, (2) determining a final fuel injection amount, TAU, in accordance with TAU=A×TP+B+J wherein A is a first learning term, B is a second learning term and J is a correction amount, (3) correcting said first learning term A by a predetermined amount in each of a series of predetermined periods in response to said ratio signal, said correcting function (3) occurring only when said engine has a load larger than a predetermined value, and (4) correcting said second learning term B by a predetermined amount in each of a series of predetermined periods in response to said ratio signal, said correcting function (4) occurring only when said engine has a load smaller than said predetermined value.
Claim 9
Independent Claim
175 words
A system for learning control of the air-fuel ratio in an electronically controlled engine comprising: means for generating an indication of engine load; means for generating a ratio signal indicative of air-fuel ratio by monitoring exhaust gases of said engine; and processing means for: (1) determining a basic fuel injection amount, TP, as a predetermined function of engine load, (2) determining a final fuel injection amount, TAU, in accordance with TAU=A×TP+B+J wherein A is a first learning term, B is a second learning term and J is a correction amount, (3) correcting said first learning term A by a predetermined amount in each of a series of predetermined periods in response to said ratio signal, said correcting function (3) occurring only when said engine has a load larger than a predetermined value, and (4) correcting said second learning term B by a predetermined amount in each of a series of predetermined periods in response to said ratio signal, said correcting function (4) occurring only when said engine has a load smaller than said predetermined value.
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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) | 1989-02-17 | 1989-08-19 | 1990-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-17 | 1993-08-19 | 1994-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-17 | 1997-08-19 | 1998-02-18 | $7700.00 | Window Closed / Lapsed |