Patent US4700675A successfully refreshed from Google Patents.
US4700675A
Expired / Lapsed
US
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Method of controlling fuel supply for internal combustion engine at idle
Assignee: Honda Motor Co Ltd
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Filing: 1986-05-28
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Granted: 1987-10-20
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Expires: 2006-05-28
Abstract
Abstract A fuel supply control method for internal combustion engines, which is capable of stabilizing the engine rotational speed to a desired idling speed immediately after the rotational speed of the engine at idle suddenly changes due to an external disturbance such as a change in the electrical load on the engine. The fuel quantity to be supplied to the engine is determined in accordance with operating conditions of the engine in the idling condition, and the determined fuel quantity is corrected by a correction value which is determined in response to the difference between a desired idling speed of the rotational speed of the engine and an actual value thereof. When the absolute value of a detected rate of change in the rotational speed of the engine is larger than a predetermined value, the correction value is corrected to thereby correct the determined fuel quantity.
Inventors
- 👤 Yutaka Otobe
- 👤 Akira Kato
- 👤 Masataka Chikamatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:50
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/02; F02D41/04; F02D41/08; F02D41/083
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
141 words
A method of controlling the quantity of fuel to be supplied to an internal combustion engine while it is operating in an idling condition, wherein the fuel quantity is determined in accordance with operating conditions of the engine in the idling condition, and the determined fuel quantity is corrected by a correction value which is determined in response to the difference between a desired idling value of the rotational speed of the engine and an actual value thereof, the method comprising the steps of: (1) detecting whether the rotational speed of the engine is varying toward a predetermined value or away from same; (2) correcting said correction value to a smaller value when the rotational speed of the engine is detected to be varying toward said predetermined value; and (3) correcting the determined fuel quantity by the correction value thus corrected.
Claim 2
Independent Claim
141 words
A method of controlling the quantity of fuel to be supplied to an internal combustion engine while it is operating in an idling condition, wherein the fuel quantity is determined in accordance with operating conditions of the engine in the idling condition, and the determined fuel quantity is corrected by a correction value which is determined in response to the difference between a desired idling value of the rotational speed of the engine and an actual value thereof, the method comprising the steps of: (1) detecting whether the rotational speed of the engine is varying toward a predetermined value or away from same; (2) correcting said correction value to a smaller value when the rotational speed of the engine is detected to be varying toward said predetermined value; and (3) correcting the determined fuel quantity by the correction value thus corrected.
Claim 3
Dependent Claim
51 words
A method as claimed in claim 1, including detecting a rate of change in the rotational speed of the engine, and wherein the correction of said corrected value in said step (2) is executed only when the absolute value of the detected rate of change is larger than a predetermined value.
Claim 4
Independent Claim
167 words
A method of controlling the quantity of fuel to be supplied to an internal combustion engine while it is operating in an idling condition, wherein the fuel quantity is determined in accordance with operating conditions of the engine in the idling condition, and the determined fuel quantity is corrected by a correction value which is determined in response to the difference between a desired idling value of the rotational speed of the engine and an actual value thereof, the method comprising the steps of: (1) setting said desired idling value at an average value of values of the rotational speed of the engine assumed during idling, said average value having an initial value dependent upon a temperature of the engine; (2) detecting a rate of change in the rotational speed of the engine; (3) correcting said correction value when the absolute value of the detected rate of change is larger than a predetermined value; and (4) correcting the determined fuel quantity by the correction value thus corrected.
Claim 5
Independent Claim
167 words
A method of controlling the quantity of fuel to be supplied to an internal combustion engine while it is operating in an idling condition, wherein the fuel quantity is determined in accordance with operating conditions of the engine in the idling condition, and the determined fuel quantity is corrected by a correction value which is determined in response to the difference between a desired idling value of the rotational speed of the engine and an actual value thereof, the method comprising the steps of: (1) setting said desired idling value at an average value of values of the rotational speed of the engine assumed during idling, said average value having an initial value dependent upon a temperature of the engine; (2) detecting a rate of change in the rotational speed of the engine; (3) correcting said correction value when the absolute value of the detected rate of change is larger than a predetermined value; and (4) correcting the determined fuel quantity by the correction value thus corrected.
Claim 6
Dependent Claim
18 words
A method as claimed in claim 3, wherein said step (3) comprises correcting said correction value to 0.
Claim 7
Independent Claim
156 words
A method of controlling the quantity of fuel to be supplied to an internal combustion engine while it is operating in an idling condition, wherein the fuel quantity is determined in accordance with operating conditions of the engine in the idling condition, and the determined fuel quantity is corrected by a correction value which is determined in response to the difference between a desired idling value of the rotational speed of the engine and an actual value thereof, the method comprising the steps of: (1) detecting a rate of change in the rotational speed of the engine; (2) correcting said correction value which is determined in response to the difference between a desired idling value of the rotational speed of the engine and an actual value thereof, when the absolute value of the detected rate of change is larger than a predetermined value; and (3) correcting the determined fuel quantity by the correction value thus corrected.
Claim 8
Independent Claim
156 words
A method of controlling the quantity of fuel to be supplied to an internal combustion engine while it is operating in an idling condition, wherein the fuel quantity is determined in accordance with operating conditions of the engine in the idling condition, and the determined fuel quantity is corrected by a correction value which is determined in response to the difference between a desired idling value of the rotational speed of the engine and an actual value thereof, the method comprising the steps of: (1) detecting a rate of change in the rotational speed of the engine; (2) correcting said correction value which is determined in response to the difference between a desired idling value of the rotational speed of the engine and an actual value thereof, when the absolute value of the detected rate of change is larger than a predetermined value; and (3) correcting the determined fuel quantity by the correction value thus corrected.
Claim 9
Dependent Claim
35 words
A method as claimed in claim 5, wherein the desired idling value of the rotational speed of the engine is an average value of values of the rotational speed of the engine assumed during idling.
Claim 10
Dependent Claim
34 words
A method as claimed in claim 6, wherein said average value of the engine rotational speed has an initial value thereof set to a desired idling value dependent upon a temperature of the engine.
Claim 11
Dependent Claim
32 words
A method as claimed in claim 6, wherein said step (3) is executed only when the rotational speed of the engine is varying toward said average value of the engine rotational speed.
Claim 12
Dependent Claim
20 words
A method as claimed in claim 5, 6, 7 or 8, wherein said step (2) comprises correction value to 0.
Claim 13
Dependent Claim
74 words
A method as claimed in claim 5, 6, 7 or 8, wherein the rotational speed of the engine is detected each time a pulse of a predetermined timing signal is generated, and said rate of change in the rotational speed of the engine is the difference between values of the rotational speed of the engine detected, respectively, upon generations of a present pulse and a preceding pulse of said predetermined timing signal during idling.
Claim 14
Dependent Claim
24 words
A method as claimed in claim 10, wherein said predetermined timing signal is a signal indicative of predetermined crank angle positions of the engine.
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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) | 1990-10-19 | 1991-04-20 | 1991-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-19 | 1995-04-20 | 1995-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-19 | 1999-04-20 | 1999-10-20 | $7700.00 | Window Closed / Lapsed |