US5387253A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spectral misfire detection system and method therefor
Assignee: Aumovio Systems Inc
•
Filing: 1992-12-28
•
Granted: 1995-02-07
•
Expires: 2012-12-28
Abstract
Abstract A system, and corresponding method, for detecting the presence of a misfire condition by interpreting spectral activity of a running engine includes a device (309, 313) for measuring a characteristic, preferably an acceleration characteristic indicative of the running engine's performance, A spectral discrimination device (319), preferably a digital filter, receives a composite signal (317) provided by the measuring device (309, 313). The digital filter (319) provides a normal firing signal (321), corresponding to spectral energy attributable to a portion of the composite signal (317) representative of a normal firing condition in the running engine, and a misfire signal (323), corresponding to spectral energy attributable to another portion of the composite signal (317) representative of a misfiring condition in the running engine. A comparison device (325) provides and indication of a misfire condition (327) when a magnitude of the misfire signal (323) exceeds a magnitude of the normal firing signal (321).
Inventors
- 👤 Donald J. Remboski, Jr.
- 👤 Kevin J. Bush
- 👤 John F. Foley
- 👤 David Frankowski
- 👤 Steven L. Plee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:45
CPC Classifications
G; G01; G01M; G01M15/00; G01M15/04; G01M15/11
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
149 words
A system for detecting a misfire condition by interpreting acceleration activity of a running engine comprising: means for measuring an acceleration of said running engine, and for providing a composite signal representative of said engine's acceleration; acceleration discrimination means for receiving the composite signal provided by said means for measuring, and for providing a normal firing signal, corresponding to acceleration behavior attributable to a portion of the composite signal representative of a normal firing condition and, concurrent to the provision of the normal firing signal, for providing a misfire signal, corresponding to acceleration behavior attributable to another portion of the composite signal representative of a misfiring condition; and comparison means for receiving the normal firing signal and the misfire signal, both signals provided by said acceleration discrimination means, and for providing a misfire indication when a magnitude of the misfire signal exceeds a magnitude of the normal firing signal.
Claim 2
Independent Claim
149 words
A system for detecting a misfire condition by interpreting acceleration activity of a running engine comprising: means for measuring an acceleration of said running engine, and for providing a composite signal representative of said engine's acceleration; acceleration discrimination means for receiving the composite signal provided by said means for measuring, and for providing a normal firing signal, corresponding to acceleration behavior attributable to a portion of the composite signal representative of a normal firing condition and, concurrent to the provision of the normal firing signal, for providing a misfire signal, corresponding to acceleration behavior attributable to another portion of the composite signal representative of a misfiring condition; and comparison means for receiving the normal firing signal and the misfire signal, both signals provided by said acceleration discrimination means, and for providing a misfire indication when a magnitude of the misfire signal exceeds a magnitude of the normal firing signal.
Claim 3
Dependent Claim
30 words
An apparatus in accordance with claim 1 wherein said means for measuring an acceleration comprises means for measuring engine angular acceleration corresponding to an angular displacement of said running engine.
Claim 4
Dependent Claim
26 words
An apparatus in accordance with claim 1 wherein said means for measuring an acceleration comprises means for measuring acceleration corresponding to vibration of said running engine.
Claim 5
Dependent Claim
31 words
An apparatus in accordance with claim 1 wherein said means for measuring an acceleration comprises means for measuring an in-cylinder combustion phenomena dependent on an acceleration behavior of said running engine.
Claim 6
Dependent Claim
25 words
An apparatus in accordance with claim 1 further comprising means for shutting off fuel to a cylinder, responsive to the provision of said misfire indication.
Claim 7
Dependent Claim
83 words
An apparatus in accordance with claim 1 wherein said acceleration discrimination means comprises a normal firing acceleration discrimination means responsive to spectral energy attributable to a portion of the composite signal representative of a normal firing condition, and a misfiring signal acceleration discrimination means responsive to spectral energy attributable to a portion of the composite signal representative of a misfiring condition, wherein said misfiring signal acceleration discrimination means is spectrally discriminatory a predetermined fixed spectral distance below said normal firing spectral discrimination means.
Claim 8
Dependent Claim
42 words
An apparatus in accordance with claim 6 wherein said misfiring signal spectral discrimination means comprises multiple spectral discrimination means predominantly responsive to frequencies located at one-half, one, and three-halves cycles/revolution of a predominant spectral location of the normal firing spectral discrimination means.
Claim 9
Dependent Claim
54 words
An apparatus in accordance with claim 7 further comprising: means for providing a synchronization signal representative of said running engine's speed; and wherein said means for measuring an acceleration of said running engine measures said acceleration at a sample rate responsive to the synchronization signal provided by said means for providing a synchronization signal.
Claim 10
Dependent Claim
19 words
An apparatus in accordance with claim 6 wherein a predominant spectral location of said acceleration discrimination means are tunable.
Claim 11
Dependent Claim
48 words
An apparatus in accordance with claim 9 further comprising: means for providing a synchronization signal representative of said running engine's speed; and wherein the predominant spectral location of said acceleration discrimination means is tuned responsive to the synchronization signal provided by said means for providing a synchronization signal.
Claim 12
Dependent Claim
48 words
An apparatus in accordance with claim 1 wherein said means for measuring an acceleration measures the acceleration independent of a measurement path length between a motion associated with the acceleration indicative of performance of a combustion process of said running engine and said means for measuring the acceleration.
Claim 13
Dependent Claim
37 words
An apparatus in accordance with claim 1 wherein said means for measuring an acceleration measures the acceleration independent of a measurement path length between said running engine and said means for measuring in a multiple cylinder engine.
Claim 14
Dependent Claim
34 words
An apparatus in accordance with claim 12 wherein a coupling media used by said means for measuring an acceleration asserts no load on the engine and has no substantial effect on the acceleration measured.
Claim 15
Independent Claim
145 words
An apparatus for detecting a misfire condition by interpreting acceleration activity of a running engine comprising: acceleration sensing means, coupled to said running engine, for providing a signal representative of said acceleration activity of said running engine and for providing a composite signal in response thereto; acceleration discrimination means for receiving the composite signal provided by said acceleration sensing means, and for providing a normal firing signal, corresponding to acceleration behavior attributable to a portion of the composite signal representative of a normal firing condition, and, concurrent to the provision of the normal firing signal, for providing a misfire signal, corresponding to acceleration behavior attributable to another portion of the composite signal representative of a misfiring condition; and means for providing an indication of a misfire condition when a magnitude of the misfire signal exceeds a magnitude of the firing signal by a predetermined factor.
Claim 16
Independent Claim
145 words
An apparatus for detecting a misfire condition by interpreting acceleration activity of a running engine comprising: acceleration sensing means, coupled to said running engine, for providing a signal representative of said acceleration activity of said running engine and for providing a composite signal in response thereto; acceleration discrimination means for receiving the composite signal provided by said acceleration sensing means, and for providing a normal firing signal, corresponding to acceleration behavior attributable to a portion of the composite signal representative of a normal firing condition, and, concurrent to the provision of the normal firing signal, for providing a misfire signal, corresponding to acceleration behavior attributable to another portion of the composite signal representative of a misfiring condition; and means for providing an indication of a misfire condition when a magnitude of the misfire signal exceeds a magnitude of the firing signal by a predetermined factor.
Claim 17
Dependent Claim
20 words
An apparatus in accordance with claim 14 wherein said acceleration sensing means comprises an accelerometer coupled to said running engine.
Claim 18
Dependent Claim
26 words
An apparatus in accordance with claim 14 wherein said acceleration sensing means comprises means for sensing an acceleration of a crankshaft coupled to said running engine.
Claim 19
Dependent Claim
146 words
An apparatus in accordance with claim 14 wherein said acceleration sensing means further comprises: speed sensing means for providing a synchronization signal representative of said running engine's speed; and wherein said acceleration discrimination means comprises a frequency tunable normal firing acceleration filtering means responsive to acceleration behavior attributable to a portion of the composite signal representative of a normal firing condition, and a frequency tunable misfiring signal acceleration filtering means responsive to acceleration behavior attributable to a portion of the composite signal representative of a misfiring condition, wherein said frequency tunable misfiring signal acceleration filtering means is spectrally located a predetermined fixed spectral distance below said frequency tunable normal firing acceleration filtering means and wherein both said frequency tunable normal firing acceleration filtering means, and said frequency tunable misfiring acceleration filtering means are spectrally tuned responsive to said synchronization signal provided by said speed sensing means.
Claim 20
Dependent Claim
45 words
An apparatus in accordance with claim 17 wherein said frequency tunable misfiring signal acceleration filtering means comprises multiple acceleration filtering means predominantly responsive to acceleration spectra located at one-half, one, and three-halves cycles/revolution of a predominant spectral location of the normal firing spectral discrimination means.
Claim 21
Independent Claim
204 words
An apparatus for detecting the presence of a misfire condition by interpreting acceleration activity of a running engine comprising: non-audio acceleration sensing means, coupled to said running engine, for providing an acceleration signal representative of said acceleration activity of said running engine; speed sensing means for providing a synchronization signal representative of said running engine's speed; firing signal tunable filter means for receiving the acceleration signal from said non-audio acceleration sensing means, and for providing a firing signal representative of a firing portion of the acceleration signal, wherein said firing signal tunable filter means is tuned responsive to the synchronization signal provided by said speed sensing means; misfiring signal tunable filter means, located a fixed spectral distance below said firing signal tunable filter means, for receiving the acceleration signal from said non-audio acceleration sensing means, and concurrent to the provision of the normal firing signal for providing a misfiring signal representative of a misfiring portion of the acceleration signal, wherein said misfiring signal tunable filter means is tuned responsive to the synchronization signal provided by said speed sensing means; and comparison means for providing an indication of a misfire condition when a magnitude of the misfire signal exceeds a magnitude of the firing signal.
Claim 22
Independent Claim
204 words
An apparatus for detecting the presence of a misfire condition by interpreting acceleration activity of a running engine comprising: non-audio acceleration sensing means, coupled to said running engine, for providing an acceleration signal representative of said acceleration activity of said running engine; speed sensing means for providing a synchronization signal representative of said running engine's speed; firing signal tunable filter means for receiving the acceleration signal from said non-audio acceleration sensing means, and for providing a firing signal representative of a firing portion of the acceleration signal, wherein said firing signal tunable filter means is tuned responsive to the synchronization signal provided by said speed sensing means; misfiring signal tunable filter means, located a fixed spectral distance below said firing signal tunable filter means, for receiving the acceleration signal from said non-audio acceleration sensing means, and concurrent to the provision of the normal firing signal for providing a misfiring signal representative of a misfiring portion of the acceleration signal, wherein said misfiring signal tunable filter means is tuned responsive to the synchronization signal provided by said speed sensing means; and comparison means for providing an indication of a misfire condition when a magnitude of the misfire signal exceeds a magnitude of the firing signal.
Claim 23
Independent Claim
133 words
An apparatus for detecting a misfire condition by interpreting acceleration of a running engine comprising: means for sensing acceleration, coupled to said running engine, and for providing an acceleration signal dependent on the sensed acceleration comprising a fundamental frequency component, irrespective of engine firing conditions, and concurrent to the provision of the acceleration signal for providing an acceleration signal comprising fractional harmonics of the fundamental frequency component when a misfire occurs; engine speed detection means for detecting the speed of the engine and for providing a signal representative of said running engine speed; and acceleration analyzing means, including comparison means, for analyzing the provided acceleration signal on dependent on the engine speed signal, thereby detecting misfire, if an energy of the fractional harmonics exceeds an energy of the fundamental by a predetermined factor.
Claim 24
Independent Claim
133 words
An apparatus for detecting a misfire condition by interpreting acceleration of a running engine comprising: means for sensing acceleration, coupled to said running engine, and for providing an acceleration signal dependent on the sensed acceleration comprising a fundamental frequency component, irrespective of engine firing conditions, and concurrent to the provision of the acceleration signal for providing an acceleration signal comprising fractional harmonics of the fundamental frequency component when a misfire occurs; engine speed detection means for detecting the speed of the engine and for providing a signal representative of said running engine speed; and acceleration analyzing means, including comparison means, for analyzing the provided acceleration signal on dependent on the engine speed signal, thereby detecting misfire, if an energy of the fractional harmonics exceeds an energy of the fundamental by a predetermined factor.
Claim 25
Dependent Claim
29 words
An apparatus in accordance with claim 20 wherein said means for sensing acceleration comprises means for measuring engine angular acceleration corresponding to an angular displacement of said running engine.
Claim 26
Dependent Claim
42 words
An apparatus in accordance with claim 21 wherein said acceleration analyzing means for analyzing the provided signal on the basis of the engine speed has a fixed frequency response and a sampling rate for analyzing the provided signal responsive to engine speed.
Claim 27
Independent Claim
160 words
A method for detecting a misfire condition by interpreting acceleration of a running engine comprising the steps of: measuring an acceleration of said running engine, wherein the acceleration is indicative of said running engine's performance, and for providing a composite signal representative of said acceleration; spectrally discriminating the composite signal provided in said step of measuring, and for providing a normal firing signal corresponding to spectral energy attributable to a portion of the composite signal representative of a normal firing condition in said running engine, and, concurrent to the provision of the normal firing signal, for providing a misfire signal, corresponding to spectral energy attributable to another portion of the composite signal representative of a misfiring condition in said running engine; and comparing the normal firing signal and the misfire signal, both signals provided in said step of measuring, and for providing a misfire indication when a magnitude of the misfire signal exceeds a magnitude of the normal firing signal.
Claim 28
Independent Claim
160 words
A method for detecting a misfire condition by interpreting acceleration of a running engine comprising the steps of: measuring an acceleration of said running engine, wherein the acceleration is indicative of said running engine's performance, and for providing a composite signal representative of said acceleration; spectrally discriminating the composite signal provided in said step of measuring, and for providing a normal firing signal corresponding to spectral energy attributable to a portion of the composite signal representative of a normal firing condition in said running engine, and, concurrent to the provision of the normal firing signal, for providing a misfire signal, corresponding to spectral energy attributable to another portion of the composite signal representative of a misfiring condition in said running engine; and comparing the normal firing signal and the misfire signal, both signals provided in said step of measuring, and for providing a misfire indication when a magnitude of the misfire signal exceeds a magnitude of the normal firing signal.
Claim 29
Dependent Claim
30 words
A method in accordance with claim 23 wherein said step of measuring acceleration comprises a step of measuring engine angular acceleration corresponding to an angular displacement of said running engine.
Claim 30
Dependent Claim
27 words
A method in accordance with claim 24 further comprising a step of shutting off fuel to a cylinder, responsive to the step of providing a misfire indication.
Claim 31
Dependent Claim
27 words
A method in accordance with claim 23 wherein said step of measuring acceleration comprises a step of measuring acceleration corresponding to a vibration of said running engine.
Claim 32
Dependent Claim
31 words
A method in accordance with claim 23 wherein said step of measuring acceleration comprises a step of measuring an in-cylinder combustion phenomena dependent on an acceleration behavior of said running engine.
Claim 33
Independent Claim
174 words
A method for detecting a misfire condition by interpreting acceleration of a running engine comprising the steps of: non-audio acceleration sensing said running engine, and providing an acceleration signal representative of said acceleration of said running engine; sensing a speed of said running engine and providing a synchronization signal representative of said running engine's speed; firing spectral filtering, tuned responsive to the synchronization signal provided by said speed sensing means, the spectral signal provided from said step of non-audio acceleration sensing, and providing a firing signal representative of a firing portion of the spectral signal; misfire spectral filtering, tuned responsive to the synchronization signal provided by said speed sensing means, the spectral signal provided from said step of non-audio acceleration sensing, and concurrent to the provision of the firing signal providing a misfiring signal representative of a misfiring portion of the spectral signal; and comparing said firing signal and said misfiring signal and providing an indication of a misfire condition when a magnitude of the misfire signal exceeds a magnitude of the firing signal.
Claim 34
Independent Claim
174 words
A method for detecting a misfire condition by interpreting acceleration of a running engine comprising the steps of: non-audio acceleration sensing said running engine, and providing an acceleration signal representative of said acceleration of said running engine; sensing a speed of said running engine and providing a synchronization signal representative of said running engine's speed; firing spectral filtering, tuned responsive to the synchronization signal provided by said speed sensing means, the spectral signal provided from said step of non-audio acceleration sensing, and providing a firing signal representative of a firing portion of the spectral signal; misfire spectral filtering, tuned responsive to the synchronization signal provided by said speed sensing means, the spectral signal provided from said step of non-audio acceleration sensing, and concurrent to the provision of the firing signal providing a misfiring signal representative of a misfiring portion of the spectral signal; and comparing said firing signal and said misfiring signal and providing an indication of a misfire condition when a magnitude of the misfire signal exceeds a magnitude of the firing signal.
Claim 35
Independent Claim
183 words
An apparatus for detecting a misfire condition by interpreting spectral activity of a running engine comprising: means for measuring a characteristic, indicative of performance of a combustion process of said running engine, and for providing a composite spectral signal representative of the performance of said combustion process; noise spectral discrimination means for receiving the composite spectral signal provided by said means for measuring a characteristic, and for providing a noise filtered signal absent of a predetermined noise component of the composite spectral signal; spectral discrimination means for receiving the noise filtered signal provided by said noise spectral discrimination means, and for providing a normal firing signal, corresponding to spectral energy attributable to a portion of the composite signal representative of a normal firing condition in said running engine, and for providing a misfire signal, corresponding to spectral energy attributable to another portion of the composite signal representative of a misfiring condition in said running engine; and means for providing an indication of a misfire condition when a magnitude of the misfire signal exceeds a magnitude of the firing signal by a predetermined factor.
Claim 36
Independent Claim
183 words
An apparatus for detecting a misfire condition by interpreting spectral activity of a running engine comprising: means for measuring a characteristic, indicative of performance of a combustion process of said running engine, and for providing a composite spectral signal representative of the performance of said combustion process; noise spectral discrimination means for receiving the composite spectral signal provided by said means for measuring a characteristic, and for providing a noise filtered signal absent of a predetermined noise component of the composite spectral signal; spectral discrimination means for receiving the noise filtered signal provided by said noise spectral discrimination means, and for providing a normal firing signal, corresponding to spectral energy attributable to a portion of the composite signal representative of a normal firing condition in said running engine, and for providing a misfire signal, corresponding to spectral energy attributable to another portion of the composite signal representative of a misfiring condition in said running engine; and means for providing an indication of a misfire condition when a magnitude of the misfire signal exceeds a magnitude of the firing signal by a predetermined factor.
Claim 37
Dependent Claim
25 words
A device in accordance with claim 29 wherein said characteristic is associated with an acceleration effect corresponding to the combustion process of said running engine.
Claim 38
Dependent Claim
28 words
A device in accordance with claim 29 wherein said spectral discrimination means comprises a digital filter with fixed filter coefficients and a sampling rate responsive to engine speed.
Claim 39
Dependent Claim
29 words
A device in accordance with claim 29 wherein said spectral discrimination means comprises a digital filter with a fixed data rate and variable filter coefficients corresponding to engine speed.
References Cited (Backward Citations)
US3908366A
Cited
US3924457A
Cited
US4083234A
Cited
US4357662A
Cited
US4380800A
Cited
US4372269A
Cited
US4438647A
Cited
US4424709A
Cited
US4697561A
Cited
US4766863A
Cited
WO1990002871A1
Cited
US4936277A
Cited
US4932379A
Cited
DE4002208A1
Cited
WO1991011599A1
Cited
US5076098A
Cited
US5088318A
Cited
US5239473A
Cited
US5200899A
Cited
US5105181A
Cited
US5095742A
Cited
US5109695A
Cited
US5044194A
Cited
US5044195A
Cited
DE4131383A1
Cited
DE4208131A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-02-06 | 1998-08-08 | 1999-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-02-06 | 2002-08-08 | 2003-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-02-06 | 2006-08-08 | 2007-02-07 | $7700.00 | Window Closed / Lapsed |