Patent US4620518A successfully refreshed from Google Patents.
US4620518A
Expired / Lapsed
US
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System for controlling the ignition timing of an internal combustion engine
Assignee: Subaru Corp
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Filing: 1985-12-24
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Granted: 1986-11-04
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Expires: 2005-12-24
Abstract
Abstract A system is provided for quickly converging the ignition timing to a desired timing when a large deviation occurs in ignition timing. The system comprises rough correcting operation for roughly correcting the ignition timing to a desired ignition timing and for producing a completion signal when the correction reaches a complete state, fine correcting operation responsive to the completion signal for finely correcting the ignition timing by a correcting quantity. When the correcting quantity becomes larger than a predetermined value, the rough correcting operation restarts, so that a large deviation of the ignition timing is quickly deviated.
Inventors
- 👤 Masaaki Nagai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:37
CPC Classifications
F; F02; F02P; F02P5/00; F02P5/04; F02P5/145; F02P5/15; F02P5/152; F02P5/1527; F02P5/1521; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
160 words
A system for controlling the ignition timing of an internal combustion engine having a microprocessor and an ignition timing control device comprising: sensing means for sensing operating conditions of the engine and for producing an engine operating condition signal; a knock sensor for sensing engine knock and for producing a knock signal; rough correcting means responsive to a start signal and to the engine operating condition signal and knock signal for roughly correcting the ignition timing to a desired ignition timing and for producing a completion signal when the correction reaches a complete state; fine correcting means responsive to the completion signal and to the engine operating condition signal and knock signal for finely correcting the ignition timing by a correcting quantity; deciding means for deciding a variation of the correcting quantity and for producing the start signal when the correcting quantity becomes larger than a predetermined value, whereby the rough correcting means restarts in response to the start signal.
Claim 2
Independent Claim
160 words
A system for controlling the ignition timing of an internal combustion engine having a microprocessor and an ignition timing control device comprising: sensing means for sensing operating conditions of the engine and for producing an engine operating condition signal; a knock sensor for sensing engine knock and for producing a knock signal; rough correcting means responsive to a start signal and to the engine operating condition signal and knock signal for roughly correcting the ignition timing to a desired ignition timing and for producing a completion signal when the correction reaches a complete state; fine correcting means responsive to the completion signal and to the engine operating condition signal and knock signal for finely correcting the ignition timing by a correcting quantity; deciding means for deciding a variation of the correcting quantity and for producing the start signal when the correcting quantity becomes larger than a predetermined value, whereby the rough correcting means restarts in response to the start signal.
Claim 3
Dependent Claim
20 words
The system according to claim 1 wherein the operating conditions of the engine includes gasoline octane value and engine speed.
Claim 4
Dependent Claim
27 words
The system according to claim 2 wherein the fine correcting means responds to the intensity of the knock and the period in which knock does not occur.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-03 | 1990-05-05 | 1990-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-03 | 1994-05-05 | 1994-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-03 | 1998-05-05 | 1998-11-04 | $7700.00 | Window Closed / Lapsed |