US5275142A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air-fuel ratio optimization logic for an electronic engine control systems
Assignee: MARATHON ENGINE SYSTEMS Inc
•
Filing: 1992-06-16
•
Granted: 1994-01-04
•
Expires: 2012-06-16
Abstract
Abstract An air-fuel optimization logic for an electronic engine control system for optimizing the efficiency of a heat engine. The engine control system has a governor generating fuel command signals to maintain speed of the engine at a desired speed, means for generating a reference air-fuel ratio signal, means responsive to the fuel command signal and the air-fuel ratio signal for supplying air to the engine, and means responsive to the fuel command signal for supplying fuel to the engine. The air-fuel optimization logic has means responsive to a change in the fuel command signal to generate an optimized air-fuel ratio offset signal which when summed with the a reference air-fuel ratio signal produces an optimized air-fuel ratio signal. The air-fuel optimization logic increments the reference air-fuel ratio signal to find a lean offset and decrements the reference air-fuel ratio signal to find a rich offset. The lean and rich offsets are averaged to generate the optimized air-fuel ratio offset.
Inventors
- 👤 Daniel R. Kapellen
- 👤 Nick Dicosola
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:37
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/02; F02D41/14; F02D41/1401; F02D41/1406; F02D31/00; F02D31/001; F02D31/007
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
172 words
An engine control system for a heat engine having air delivery means for supply air to said engine, fuel delivery means for supply fuel to said engine, and an actual engine speed sensor generating an actual engine speed signal, said engine control system comprising: governor means responsive to said actual speed signal for generating a fuel command signal corresponding to a fuel rate determined to maintain the speed of said engine at a desired speed; air-fuel optimization means for generating an optimized air-fuel ratio signal having a value optimizing the operating efficiency of said engine in response to said fuel command signal; air control means for actuating said air delivery means to supply air to said engine at an air flow rate corresponding in value of the product of said optimized air-fuel ratio signal and said fuel command signal; and fuel control means for actuating said fuel delivery means to deliver fuel to said engine at said fuel rate determined to maintain said actual speed of said engine at said desired speed.
Claim 2
Dependent Claim
172 words
An engine control system for a heat engine having air delivery means for supply air to said engine, fuel delivery means for supply fuel to said engine, and an actual engine speed sensor generating an actual engine speed signal, said engine control system comprising: governor means responsive to said actual speed signal for generating a fuel command signal corresponding to a fuel rate determined to maintain the speed of said engine at a desired speed; air-fuel optimization means for generating an optimized air-fuel ratio signal having a value optimizing the operating efficiency of said engine in response to said fuel command signal; air control means for actuating said air delivery means to supply air to said engine at an air flow rate corresponding in value of the product of said optimized air-fuel ratio signal and said fuel command signal; and fuel control means for actuating said fuel delivery means to deliver fuel to said engine at said fuel rate determined to maintain said actual speed of said engine at said desired speed.
Claim 3
Dependent Claim
59 words
The engine control system of claim 1 wherein said air-fuel optimization means comprises: means for generating a reference air-fuel ratio signal; air-fuel optimization logic responsive to said fuel command signal for generating an air-fuel ratio offset signal; and means for summing said air-fuel ratio offset signal with said reference air-fuel ratio signal to generate said optimized air-fuel ratio signal.
Claim 4
Dependent Claim
112 words
The engine control system of claim 2 wherein said air-fuel optimization logic comprises: means for generating an average fuel command value in response to said fuel command signal generated by said governor means; fuel command detecting means for detecting a change in said average fuel command signal; means for generating a lean offset signal in response to said fuel command detecting means detecting a change in said fuel command signal; means for generating a rich offset signal in response to said fuel command detecting means detecting a change in said fuel command signal; and means for generating said air-fuel ratio offset signal from said lean offset signal and said rich offset signal.
Claim 5
Dependent Claim
41 words
The engine control system of claim 3 wherein said means for generating said air-fuel offset signal comprises means for generating said air-fuel offset signal having a value equal to the average of said lean offset signal and said rich offset signal.
Claim 6
Dependent Claim
136 words
The engine control system of claim 3 wherein said means for generating said lean offset signal comprises: means for incrementing said air-fuel ratio offset signal in response to said fuel command detecting means detecting a change in said fuel command signal; means for terminating the incrementing of said air-fuel ratio offset in response to said fuel command signal increasing by a predetermined percentage of a minimum value to generate a lean fuel command signal; means for comparing the value of said lean fuel command signal with a predeterminable value to determine a difference in the values; and means for storing the value of said incremented air-fuel offset signal as said lean offset signal in response to the values of said lean fuel command signal and said predetermined value being within a predetermined percentage of each other.
Claim 7
Dependent Claim
145 words
The engine control system of claim 5 wherein said means for generating said rich offset signal comprises: means for decrementing said air-fuel ratio offset signal in response to said command signal detection means detecting a change in said command signal; means for terminating the decrementing of the value of said air-fuel ratio offset signal in response to the value of said fuel command signal increasing by said predetermined percentage of said minimum value to generate a rich fuel command signal; means for comparing the value of said rich fuel command signal to the value of said lean fuel command signal to determine a difference in their values; and means for storing the value of said decremented air-fuel offset signal as said rich offset signal in response to the values of said lean offset and said rich offset being within said predetermined percentage of each other.
Claim 8
Dependent Claim
29 words
The engine control system of claim 6 wherein said predeterminable value of said means for generating a lean offset signal is the value of said rich fuel command signal.
Claim 9
Dependent Claim
133 words
The engine control system of claim 7 wherein said means for generating a lean offset signal includes a lean offset found flag indicating a value of said lean offset has been found and means for setting said lean offset flag in response to said difference in the values of said lean offset signal and said rich offset signal being less than said predetermined percentage of the value of said lean offset signal, and wherein said means for generating said rich offset signal includes a rich offset found flag indicating a value of said rich offset signal has been found and means for setting said rich offset flag in response to said difference in the values of said lean offset signal and said rich offset signal being within said predetermined percentage of each other.
Claim 10
Dependent Claim
102 words
The engine control system of claim 8 wherein said means for generating a lean offset signal includes means for resetting said rich offset found flag in response to said difference between the value of said lean fuel command signal and the value of said rich fuel command signal being greater than said predetermined percentage and wherein said means for generating a rich offset signal includes means for resetting said lean offset found flag in response to said difference between the value of said rich fuel command signal and the value of said lean fuel command signal being greater than said predetermined percentage.
Claim 11
Independent Claim
183 words
A method for controlling the air-fuel ratio of a heat engine to optimize its efficiency, said heat engine having an air delivery means for supplying air to said engine, fuel delivery means for delivering fuel to said engine, and an engine speed sensor generating an actual engine speed signal, said method comprising the steps of: generating a fuel command signal corresponding to a fuel rate determined to maintain said actual engine speed at a desired engine speed; generating an optimized air fuel ratio signal in response to said fuel command signal, said optimized air-fuel ratio signal having a value optimizing the operating efficiency of the engine; actuating said air delivery means to supply air to said engine at an air flow rate corresponding in value to the product of said optimized air-fuel ratio signal and said fuel command signal; and actuating said fuel delivery means to deliver fuel to said engine in response to said fuel command signal, said fuel delivery means delivering fuel to said engine at a flow rate determined to maintain said actual engine speed as said desired engine speed.
Claim 12
Independent Claim
183 words
A method for controlling the air-fuel ratio of a heat engine to optimize its efficiency, said heat engine having an air delivery means for supplying air to said engine, fuel delivery means for delivering fuel to said engine, and an engine speed sensor generating an actual engine speed signal, said method comprising the steps of: generating a fuel command signal corresponding to a fuel rate determined to maintain said actual engine speed at a desired engine speed; generating an optimized air fuel ratio signal in response to said fuel command signal, said optimized air-fuel ratio signal having a value optimizing the operating efficiency of the engine; actuating said air delivery means to supply air to said engine at an air flow rate corresponding in value to the product of said optimized air-fuel ratio signal and said fuel command signal; and actuating said fuel delivery means to deliver fuel to said engine in response to said fuel command signal, said fuel delivery means delivering fuel to said engine at a flow rate determined to maintain said actual engine speed as said desired engine speed.
Claim 13
Dependent Claim
68 words
The method of claim 10 wherein said step of generating an optimized air-fuel ratio comprises the steps of: generating a lean offset signal in response to detecting a change in said fuel command signal; generating a rich offset signal in response to detecting said change in said fuel command signal; and generating said air-fuel ratio offset signal from the values of said lean offset and rich offset signals.
Claim 14
Dependent Claim
43 words
The method of claim 11 wherein said step of generating said air-fuel ratio offset signal comprises the step of generating said air-fuel ratio offset signal having a value which is the average of the values of said lean offset and rich offset signals.
Claim 15
Dependent Claim
146 words
The method of claim 11 wherein said step of generating said lean offset signal comprises the steps of: incrementing said air-fuel ratio offset signal in response to the value of said fuel command signal changing by less than a first predetermined percentage; terminating the incrementing of said air-fuel offset signal in response to the value of said fuel command signal changing by more than said first predetermined percentage, said fuel command signal changed by more than said first predetermined percentage being a lean fuel command signal; comparing the value of said lean fuel command signal to a predeterminable value to determine a difference in their values; and storing the value of said incremented air-fuel offset signal as said lean offset signal in response to said difference in the values of said lean fuel command signal and said predeterminable value being less than a second predetermined percentage.
Claim 16
Dependent Claim
147 words
The method of claim 13 wherein said step of generating a rich offset signal comprises the steps of: decrementing said air-fuel ratio offset signal in response to the value of said fuel command signal changing by less than said first predetermined percentage; terminating the decrementing of said air-fuel ratio offset signal in response to said fuel command signal changing by more than said first predetermined percentage, said fuel command signal changed by said first predetermined percentage being a rich fuel command signal; comparing the value of said rich fuel command signal to the value of said lean fuel command signal to determine a difference in their values; and storing the value of said decremented air-fuel offset signal as said rich offset signal in response to said difference in the values of said rich fuel command and lean fuel command signals being less than said second predetermined percentage.
Claim 17
Dependent Claim
34 words
The method of claim 14 wherein said step of comparing the value of said lean fuel command signal to a predeterminable value compares said lean fuel command signal to said rich fuel command signal.
Claim 18
Dependent Claim
152 words
The method of claim 15 wherein said step of generating a lean offset signal further includes the steps of: setting a lean offset found flag in response to said difference in the values of said lean and rich fuel command signals being less than said second predetermined percentage; and resetting a rich offset found flag in response to said difference in the values of said lean and rich fuel command signals being greater than said second predetermined percentage; and wherein said step of generating a rich offset signal further includes the steps of: setting said rich offset found flag in response to said difference in the values of said lean and rich fuel command signals being less than said second predetermined percentage; and resetting said lean offset found flag in response to said difference in the values of said lean and rich fuel command signals being greater than said second predetermined percentage.
Claim 19
Dependent Claim
148 words
An air-fuel optimization logic for optimizing the operation of a heat engine having a governor for generating a fuel command signal corresponding to a fuel flow rate required to maintain the engine speed at a desired speed, means for generating a reference air-fuel ratio signal, and means responsive to said fuel command signal and said air-fuel ratio signal for supplying air to said engine wherein the air fuel ratio of said air and fuel being supplied to said engine is equal to said reference air-fuel ratio, said air-fuel optimization logic comprising: means responsive to said fuel command signal for generating an air-fuel ratio offset signal which when summed with said air-fuel ratio signal generates an optimized air-fuel ratio signal which optimizes the efficiency of operation of said engine; and means for summing said air-fuel offset signal to said air-fuel reference signal to generate said optimized air-fuel ratio signal.
Claim 20
Dependent Claim
148 words
An air-fuel optimization logic for optimizing the operation of a heat engine having a governor for generating a fuel command signal corresponding to a fuel flow rate required to maintain the engine speed at a desired speed, means for generating a reference air-fuel ratio signal, and means responsive to said fuel command signal and said air-fuel ratio signal for supplying air to said engine wherein the air fuel ratio of said air and fuel being supplied to said engine is equal to said reference air-fuel ratio, said air-fuel optimization logic comprising: means responsive to said fuel command signal for generating an air-fuel ratio offset signal which when summed with said air-fuel ratio signal generates an optimized air-fuel ratio signal which optimizes the efficiency of operation of said engine; and means for summing said air-fuel offset signal to said air-fuel reference signal to generate said optimized air-fuel ratio signal.
Claim 21
Dependent Claim
78 words
The air-fuel optimization logic of claim 17 wherein said means for generating an air-fuel ratio offset signal comprises: means for generating a lean offset signal in response to a change in said air-fuel command from an average fuel command; means for generating a rich offset signal in response to a change in said air-fuel command from an average fuel command; and means for generating said air-fuel ratio offset signal from said lean offset and said rich offset signals.
Claim 22
Dependent Claim
49 words
The air-fuel optimization logic of claim 18 wherein said means for generating said air-fuel ratio offset signal comprises means for generating said air-fuel ratio offset signal having a value which is an average of the value of said lean offset signal and the value of said rich offset signal.
Claim 23
Dependent Claim
124 words
The air-fuel optimization logic of claim 19 wherein said means for generating said lean offset signal comprises: means for incrementing said air-fuel ratio offset signal in response to detecting a change in said fuel command signal; means for terminating the incrementing of said air-fuel ratio offset signal in response to said fuel command signal increasing by a first predetermined percentage of a minimum value, said increased fuel command signal being a lean fuel command signal; means for comparing the value of said lean fuel command signal with a predeterminable value to generate a difference signal; and means for storing the value of said incremented offset signal as said lean offset signal in response to said difference signal being less than a second predetermined percentage.
Claim 24
Dependent Claim
132 words
The air-fuel optimization logic of claim 20 wherein said means for generating a rich offset signal comprises: means for decrementing said air-fuel ratio offset in response to detecting a change in said fuel command signal; means for terminating the decrementing of said air-fuel ratio offset signal in response to said fuel command signal increasing by said first predetermined percentage of a minimum fuel command signal, the value of said increased fuel command signal being a rich fuel command signal; means for comparing the value of said rich fuel command signal with said lean fuel command signal to generate a difference signal; and means for storing the value of said decremented offset signal as said rich offset signal in response to said difference signal being greater than a predetermined percentage of each other.
Claim 25
Dependent Claim
17 words
The air-fuel optimization logic of claim 21 wherein said predeterminable value is said rich fuel command signal.
Claim 26
Dependent Claim
143 words
The air-fuel optimization logic of claim 22 further including a lean offset found flag indicating a lean offset has been determined and a rich offset found flag indicating that said rich offset has been determined, said means for generating a lean offset signal further includes: means for setting said lean offset found flag in response to said difference signal being less than said second predetermined percentage; and means for resetting said rich offset found flag in response to said difference signal being greater than said second predetermined percentage; and wherein said means for generating a rich offset signal further includes; means for setting said rich offset found flag in response to said difference signal being less than said second predetermined percentage; and means for resetting said lean offset found flag in response to said difference signal being greater than said second predetermined percentage.
Claim 27
Independent Claim
106 words
A method for optimizing the operation of a heat engine having a governor for generating a fuel command signal corresponding to a fuel flow rate required to maintain the engine speed at a desired speed, means for generating a reference air-fuel ratio signal, and means responsive to said fuel command signal and said air-fuel ratio signal for supplying air to said engine, said method comprising the steps of: generating an air-fuel ratio offset signal in response to said fuel command signal; and summing said air-fuel ratio offset signal to said air-fuel reference signal to generate an optimized air-fuel reference signal optimizing the efficiency of said engine.
Claim 28
Independent Claim
106 words
A method for optimizing the operation of a heat engine having a governor for generating a fuel command signal corresponding to a fuel flow rate required to maintain the engine speed at a desired speed, means for generating a reference air-fuel ratio signal, and means responsive to said fuel command signal and said air-fuel ratio signal for supplying air to said engine, said method comprising the steps of: generating an air-fuel ratio offset signal in response to said fuel command signal; and summing said air-fuel ratio offset signal to said air-fuel reference signal to generate an optimized air-fuel reference signal optimizing the efficiency of said engine.
Claim 29
Dependent Claim
73 words
The method of claim 24 wherein said step of generating an air-fuel ratio offset signal comprises the steps of: generating a lean offset signal in response to a change in said air-fuel command from an average fuel command; generating a rich offset signal in response to a change in said air-fuel command from an average fuel command; and generating said air-fuel ratio offset signal from said lean offset and said rich offset signals.
Claim 30
Dependent Claim
35 words
The method of claim 25 wherein said step of generating said air-fuel ratio offset signal comprises the step of averaging the value of said lean offset signal and the value of said rich offset signal.
Claim 31
Dependent Claim
117 words
The method of claim 26 wherein said step of generating said lean offset signal comprises the steps of: incrementing said air-fuel ratio offset signal in response to detecting a change in said fuel command signal; terminating the incrementing of said air-fuel ratio offset signal in response to said fuel command signal increasing by a first predetermined percentage of a minimum value, said increased fuel command signal being a lean fuel command signal; comparing the value of said lean fuel command signal with a predeterminable value to generate a difference signal; and storing the value of said incremented offset signal as said lean offset signal in response to said difference signal being less than a second predetermined percentage.
Claim 32
Dependent Claim
125 words
A method of claim 27 wherein said step of generating a rich offset signal comprises the steps of: decrementing said air-fuel ratio offset in response to detecting a change in said fuel command signal; terminating the decrementing of said air-fuel ratio offset signal in response to said fuel command signal increasing by said first predetermined percentage of a minimum fuel command signal, the value of said increased fuel command signal being a rich fuel command signal; comparing the value of said rich fuel command signal with said lean fuel command signal to generate a difference signal; and storing the value of said decremented offset signal as said rich offset signal in response to said difference signal being greater than a predetermined percentage of each other.
Claim 33
Dependent Claim
15 words
The method of claim 28 wherein said predeterminable value is said rich fuel command signal.
Claim 34
Dependent Claim
112 words
The method of claim 29 wherein said step of generating a lean offset signal further includes the steps of: setting a lean offset found flag in response to said difference signal being less than said second predetermined percentage; and resetting a rich offset found flag in response to said difference signal being greater than said second predetermined percentage; and wherein said step of generating a rich offset signal further includes the steps of: setting said rich offset found flag in response to said difference signal being less than said second predetermined percentage; and resetting said lean offset found flag in response to said difference signal being greater than said second predetermined percentage.
References Cited (Backward Citations)
US3789816A
Cited
US4161162A
Cited
US4172433A
Cited
US4064846A
Cited
US4140083A
Cited
US4344140A
Cited
US4377143A
Cited
US4617892A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-01-03 | 1997-07-05 | 1998-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-01-03 | 2001-07-05 | 2002-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-01-03 | 2005-07-05 | 2006-01-04 | $7700.00 | Window Closed / Lapsed |