US5822710A
Expired / Lapsed
US
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Method of detecting engine speed for detecting misfires in an internal combustion engine
Assignee: Robert Bosch GmbH
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Filing: 1996-06-10
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Granted: 1998-10-13
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Expires: 2016-06-10
Abstract
Abstract The invention is directed to a method for detecting combustion misfires in a multicylinder internal combustion engine. The method includes the steps of: forming a criterion for the rough running of the engine for each cylinder individually on the basis of time intervals during which the crankshaft passes through predetermined angular ranges; and, forming corrective values from rough-running values for each cylinder individually during misfire-free operation so that the rough-running values for each individual cylinder coupled to said corrective values become equal with respect to each other.
Inventors
- 👤 Manfred Mezger
- 👤 Klaus Ries-Muller
- 👤 Rainer Frank
- 👤 Christian Kohler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:31
CPC Classifications
G; G01; G01M; G01M15/00; G01M15/04; G01M15/11; F; F02; F02D; F02D41/00; F02D41/008; F02D41/24; F02D41/2406; F02D41/2425; F02D41/2429; F02P; F02P11/00; F02P11/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
180 words
A method for detecting combustion misfires in a multicylinder internal combustion engine which cause a rough running of said engine, the method comprising the steps of: forming a criterion for the rough running of the engine for each cylinder individually on the basis of time segments during which the crankshaft passes through predetermined angular regions; forming corrective values from rough-running values for each cylinder individually during misfire-free operation so that the rough-running values for each individual cylinder coupled to said corrective values become equal with respect to each other; determining said corrective values during misfire-free normal operation for each engine individually; deliberately triggering combustion misfires to cause an increase of the rough running when compared to a misfire-free operation; determining the rough running as a consequence of the deliberately triggered combustion misfires and determining the rough running without said deliberately triggered combustion misfires; and, deeming the operation without said deliberately triggered combustion misfires to be misfire free when the rough-running values deviate to a predetermined extent from the rough-running values determined under the influence of said deliberately triggered combustion misfires.
Claim 2
Independent Claim
180 words
A method for detecting combustion misfires in a multicylinder internal combustion engine which cause a rough running of said engine, the method comprising the steps of: forming a criterion for the rough running of the engine for each cylinder individually on the basis of time segments during which the crankshaft passes through predetermined angular regions; forming corrective values from rough-running values for each cylinder individually during misfire-free operation so that the rough-running values for each individual cylinder coupled to said corrective values become equal with respect to each other; determining said corrective values during misfire-free normal operation for each engine individually; deliberately triggering combustion misfires to cause an increase of the rough running when compared to a misfire-free operation; determining the rough running as a consequence of the deliberately triggered combustion misfires and determining the rough running without said deliberately triggered combustion misfires; and, deeming the operation without said deliberately triggered combustion misfires to be misfire free when the rough-running values deviate to a predetermined extent from the rough-running values determined under the influence of said deliberately triggered combustion misfires.
Claim 3
Dependent Claim
33 words
The method of claim 1, comprising the further step of: utilizing the duration of the time segments in which the crankshaft rotates through predetermined angular regions as a measure for the rough running.
Claim 4
Dependent Claim
47 words
The method of claim 1, comprising the further step of: utilizing the differences of the times, in which the crankshaft exceeds predetermined angular ranges, as a measure for rough running with said differences being standardized to a power of a time assigned to a specific ignition stroke.
Claim 5
Dependent Claim
31 words
The method of claim 3, comprising the further step of: undertaking a dynamic compensation when forming the rough-running values by compensating the effects of changes of the rpm of the engine.
Claim 6
Independent Claim
168 words
A method for detecting combustion misfires in a multicylinder internal combustion engine which cause a rough running of said engine, the method comprising the steps of: forming a criterion for the rough running of the engine for each cylinder individually on the basis of time segments during which the crankshaft passes through predetermined angular regions; forming corrective values from rough-running values for each cylinder individually during misfire-free operation so that the rough-running values for each individual cylinder coupled to said corrective values become equal with respect to each other; deliberately triggering combustion misfires to cause an increase of the rough running hen compared to a misfire-free operation; determining first rough-running values as a consequence of the deliberately triggered combustion misfires and determining second rough running values without said deliberately triggered combustion misfires; determining a threshold value which lies between said first and second rough-running values; and, evaluating an increase of rough running values above said threshold value during operation without said deliberately triggered combustion misfires as a misfire.
Claim 7
Independent Claim
168 words
A method for detecting combustion misfires in a multicylinder internal combustion engine which cause a rough running of said engine, the method comprising the steps of: forming a criterion for the rough running of the engine for each cylinder individually on the basis of time segments during which the crankshaft passes through predetermined angular regions; forming corrective values from rough-running values for each cylinder individually during misfire-free operation so that the rough-running values for each individual cylinder coupled to said corrective values become equal with respect to each other; deliberately triggering combustion misfires to cause an increase of the rough running hen compared to a misfire-free operation; determining first rough-running values as a consequence of the deliberately triggered combustion misfires and determining second rough running values without said deliberately triggered combustion misfires; determining a threshold value which lies between said first and second rough-running values; and, evaluating an increase of rough running values above said threshold value during operation without said deliberately triggered combustion misfires as a misfire.
Claim 8
Dependent Claim
30 words
The method of claim 5, comprising the further step of: determining a threshold value on the basis of the statistical distribution of the rough-running values with and without said measures.
Claim 9
Dependent Claim
26 words
The method of claim 6, comprising the further step of: storing the determined rough-running values for each cylinder individually and in dependence upon load and rpm.
Claim 10
Dependent Claim
27 words
The method of claim 7, comprising the further step of: extending threshold vales learned in the operating ranges with low catalytic converter temperatures to other operating ranges.
References Cited (Backward Citations)
US4780826A
Cited
US5487008A
Cited
US5216915A
Cited
US5197325A
Cited
US5044195A
Cited
US5426587A
Cited
DE4138765A1
Cited
US5263365A
Cited
US5428991A
Cited
WO1993020427A1
Cited
US5357788A
Cited
EP0576705A1
Cited
EP0583496A1
Cited
EP0583495B1
Cited
US5544058A
Cited
US5452604A
Cited
US5495415A
Cited
WO1995027848A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-10-12 | 2002-04-13 | 2002-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-10-12 | 2006-04-13 | 2006-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-10-12 | 2010-04-13 | 2010-10-13 | $7700.00 | Window Closed / Lapsed |