US4679536A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Engine combustion condition detecting system and method
Assignee: Nissan Motor Co Ltd
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Filing: 1985-09-30
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Granted: 1987-07-14
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Expires: 2005-09-30
Abstract
Abstract Pressure within an engine combustion chamber is sensed. The timing at which the sensed pressure peaks is detected, and the interval between the moment of spark generation and the detected timing of the pressure peak is measured. The presently detected timing of the pressure peak is selectively adopted or ignored in accordance with the measured interval. When the presently detected timing of the pressure peak is ignored, the previously accepted timing value of the pressure peak is adopted in its place.
Inventors
- 👤 Tatsuo Morita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:50
CPC Classifications
F; F02; F02P; F02P5/00; F02P5/04; F02P5/145; F02P5/1455; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
230 words
A system for an engine including a combustion chamber in which combustion is induced periodically by generating a spark, the system comprising: (a) means for sensing pressure within the combustion chamber; (b) means for detecting a timing at which the sensed pressure peaks; (c) means for measuring an interval between an occurrence of a spark generation and the timing of the pressure peak; (d) a memory; (e) means for, in accordance with a length of the presently measured interval, selectively storing the presently detected timing of the peak pressure in the memory in place of data held previously in the memory or ignoring the presently detected timing of the pressure peak so as to allow the memory to continue to hold the previously detected timing of the pressure peak, comprising: (1) means for deriving a mean value of the periodically measured intervals; (2) means for comparing the presently measured interval to a reference value which is related to the mean value of the intervals; (3) means for, when the presently measured interval is greater than the reference value, storing the presently detected timing of the pressure peak in the memory; and (4) means for, when the presently measured interval is not greater than the reference value, ignoring the presently detected timing of the pressure peak; (f) means for outputting a signal representing the detected timing currently held in the memory.
Claim 2
Independent Claim
230 words
A system for an engine including a combustion chamber in which combustion is induced periodically by generating a spark, the system comprising: (a) means for sensing pressure within the combustion chamber; (b) means for detecting a timing at which the sensed pressure peaks; (c) means for measuring an interval between an occurrence of a spark generation and the timing of the pressure peak; (d) a memory; (e) means for, in accordance with a length of the presently measured interval, selectively storing the presently detected timing of the peak pressure in the memory in place of data held previously in the memory or ignoring the presently detected timing of the pressure peak so as to allow the memory to continue to hold the previously detected timing of the pressure peak, comprising: (1) means for deriving a mean value of the periodically measured intervals; (2) means for comparing the presently measured interval to a reference value which is related to the mean value of the intervals; (3) means for, when the presently measured interval is greater than the reference value, storing the presently detected timing of the pressure peak in the memory; and (4) means for, when the presently measured interval is not greater than the reference value, ignoring the presently detected timing of the pressure peak; (f) means for outputting a signal representing the detected timing currently held in the memory.
Claim 3
Dependent Claim
29 words
The system of claim 1, further comprising means for controlling the moment of spark generation in accordance with the timing of the pressure peak represented by the output signal.
Claim 4
Dependent Claim
32 words
The system of claim 1, further comprising means for controlling the rate of fuel injection into the engine in accordance with the timing of the pressure peak represented by the output signal.
Claim 5
Dependent Claim
40 words
The system of claim 1, further comprising means for outputting a second signal indicating that the storing/ignoring means has continuously been ignoring the detected timings of the pressure peak for a reference interval or for longer than the reference interval.
Claim 6
Dependent Claim
21 words
The system of claim 4, further comprising means for controlling the moment of spark generation in accordance with the second signal.
Claim 7
Dependent Claim
24 words
The system of claim 4, further comprising means for controlling the rate of fuel injection into the engine in accordance with the second signal.
Claim 8
Independent Claim
179 words
A system for an engine including a crankshaft and a combustion chamber in which combustion is induced periodically with respect to rotation of the crankshaft, the system comprising: (a) means for sensing pressure within the combustion chamber; (b) means for periodically detecting an angle of the crankshaft at which the sensed pressure peaks; (c) means for deriving a mean value of the periodically detected peak pressure crankshaft angles; (d) means for comparing the presently detected peak pressure crankshaft angle to a reference value which is related to the mean value; (e) a memory; (f) means for, in accordance with the comparison between the presently detected peak pressure crankshaft angle and the reference value, selectively storing the presently detected peak pressure crankshaft angle in the memory in place of data held previously in the memory or ignoring the presently detected peak pressure crankshaft angle so as to allow the memory to continue to hold the previously detected peak pressure crankshaft angle; and (g) means for outputting a signal representing the detected peak pressure crankshaft angle currently held in the memory.
Claim 9
Independent Claim
179 words
A system for an engine including a crankshaft and a combustion chamber in which combustion is induced periodically with respect to rotation of the crankshaft, the system comprising: (a) means for sensing pressure within the combustion chamber; (b) means for periodically detecting an angle of the crankshaft at which the sensed pressure peaks; (c) means for deriving a mean value of the periodically detected peak pressure crankshaft angles; (d) means for comparing the presently detected peak pressure crankshaft angle to a reference value which is related to the mean value; (e) a memory; (f) means for, in accordance with the comparison between the presently detected peak pressure crankshaft angle and the reference value, selectively storing the presently detected peak pressure crankshaft angle in the memory in place of data held previously in the memory or ignoring the presently detected peak pressure crankshaft angle so as to allow the memory to continue to hold the previously detected peak pressure crankshaft angle; and (g) means for outputting a signal representing the detected peak pressure crankshaft angle currently held in the memory.
Claim 10
Dependent Claim
29 words
The system of claim 7, further comprising means for controlling the moment of spark generation in accordance with the timing of the pressure peak represented by the output signal.
Claim 11
Dependent Claim
32 words
The system of claim 7, further comprising means for controlling the rate of fuel injection into the engine in accordance with the timing of the pressure peak represented by the output signal.
Claim 12
Dependent Claim
40 words
The system of claim 7, further comprising means for outputting a second signal indicating that the storing/ignoring means has continuously been ignoring the detected timings of the pressure peak for a reference interval or for longer than the reference interval.
Claim 13
Dependent Claim
21 words
The system of claim 10, further comprising means for controlling the moment of spark generation in accordance with the second signal.
Claim 14
Dependent Claim
24 words
The system of claim 10, further comprising means for controlling the rate of fuel injection into the engine in accordance with the second signal.
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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) | 1990-07-13 | 1991-01-12 | 1991-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-13 | 1995-01-12 | 1995-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-13 | 1999-01-12 | 1999-07-14 | $7700.00 | Window Closed / Lapsed |