US5691469A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of detecting combustion misfires
Assignee: Robert Bosch GmbH
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Filing: 1996-08-29
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Granted: 1997-11-25
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Expires: 2016-08-29
Abstract
Abstract The invention is directed to a method for detecting combustion misfires in an internal combustion engine on the basis of a first signal wherein the nonuniformity of the rotational movement of the crankshaft of the engine is imaged. The method includes the steps of: generating a second signal which is periodic and has a period duration corresponding to one of the following: the cycle duration of a complete work cycle of the engine or the cycle duration divided by a whole number, and the second signal having a fixed phase relationship to the rotational movement of said crankshaft; providing an ancillary signal based on the first signal; modulating the second signal with the ancillary signal and filtering the second signal to form a third signal; and, utilizing the third signal for detecting the presence of misfires and for identifying the cylinder affected by the misfires.
Inventors
- 👤 Manfred Mezger
- 👤 Andrea Lohmann
- 👤 Klaus Ries-Muller
- 👤 Jurgen Forster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:44
CPC Classifications
G; G01; G01M; G01M15/00; G01M15/04; G01M15/11
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
142 words
A method for detecting combustion misfires in an internal combustion engine on the basis of a discrete first signal wherein the nonuniformity of the rotational movement of the crankshaft of the engine is imaged, the method comprising the steps of: generating a second signal which is periodic and has a period duration corresponding to one of the following: the cycle duration of a complete work cycle of said engine or said cycle duration divided by a whole number and said second signal having a fixed phase relationship to the rotational movement of said crankshaft; providing an ancillary signal based on said discrete first signal; modulating said second signal with said ancillary signal and filtering said second signal to form a third signal; and, utilizing said third signal for detecting the presence of misfires and for identifying the cylinder affected by said misfires.
Claim 2
Independent Claim
142 words
A method for detecting combustion misfires in an internal combustion engine on the basis of a discrete first signal wherein the nonuniformity of the rotational movement of the crankshaft of the engine is imaged, the method comprising the steps of: generating a second signal which is periodic and has a period duration corresponding to one of the following: the cycle duration of a complete work cycle of said engine or said cycle duration divided by a whole number and said second signal having a fixed phase relationship to the rotational movement of said crankshaft; providing an ancillary signal based on said discrete first signal; modulating said second signal with said ancillary signal and filtering said second signal to form a third signal; and, utilizing said third signal for detecting the presence of misfires and for identifying the cylinder affected by said misfires.
Claim 3
Dependent Claim
45 words
The method of claim 1, said third signal having a magnitude and phase and the method comprising the further step of drawing a conclusion as to the occurrence of a misfire from said magnitude, and a conclusion as to the affected cylinder from said phase.
Claim 4
Dependent Claim
24 words
The method of claim 1, first performing the step of modulating said second signal and then filtering the modulated signal with a lowpass filter.
Claim 5
Dependent Claim
21 words
The method of claim 1, comprising the step of first bandpass filtering said discrete first signal before modulating said second signal.
Claim 6
Independent Claim
170 words
A method for detecting combustion misfires in an internal combustion engine on the basis of a first signal wherein the nonuniformity of the rotational movement of the crankshaft of the engine is imaged, the method comprising the steps of: providing said first signal as a discrete first signal as a sequence of segment times (ts) which are discretely detected in accordance with the sequence of ignitions of said engine; generating a second signal which is periodic and has a period duration corresponding to one of the following: the cycle duration of a complete work cycle of said engine or said cycle duration divided by a whole number and said second signal having a fixed phase relationship to the rotational movement of said crankshaft; providing an ancillary signal based on said first signal; modulating said second signal with said ancillary signal and filtering said second signal to form a third signal; and, utilizing said third signal for detecting the presence of misfires and for identifying the cylinder affected by said misfires.
Claim 7
Independent Claim
170 words
A method for detecting combustion misfires in an internal combustion engine on the basis of a first signal wherein the nonuniformity of the rotational movement of the crankshaft of the engine is imaged, the method comprising the steps of: providing said first signal as a discrete first signal as a sequence of segment times (ts) which are discretely detected in accordance with the sequence of ignitions of said engine; generating a second signal which is periodic and has a period duration corresponding to one of the following: the cycle duration of a complete work cycle of said engine or said cycle duration divided by a whole number and said second signal having a fixed phase relationship to the rotational movement of said crankshaft; providing an ancillary signal based on said first signal; modulating said second signal with said ancillary signal and filtering said second signal to form a third signal; and, utilizing said third signal for detecting the presence of misfires and for identifying the cylinder affected by said misfires.
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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) | 2000-11-24 | 2001-05-26 | 2001-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-11-24 | 2005-05-26 | 2005-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-11-24 | 2009-05-26 | 2009-11-25 | $7700.00 | Window Closed / Lapsed |