Patent US5732675A successfully refreshed from Google Patents.
US5732675A
Expired / Lapsed
US
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Air/fuel ratio control apparatus for direct injection engine
Assignee: Hitachi Ltd
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Filing: 1997-01-24
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Granted: 1998-03-31
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Expires: 2017-01-24
Abstract
Abstract A control unit 15 of an air/fuel ratio control apparatus according to the present invention takes in signals output from various sensors detecting operational states of an engine, and controls the fuel injection amount and the ignition timing by executing the predetermined processing by using the taken-in signals, and outputting control signals obtained by the processing to each injector and an ignition coil connected to each ignition plug. Further, the amount to be injected in each cylinder is corrected, based on the integration value of fuel pressure changes detected by the fuel pressure sensor, on the basis of the found fact that the integration value of the fuel pressure changes for each cylinder well corresponds to the amount actually injected into the cylinder.
Inventors
- 👤 Yoshiyuki Yoshida
- 👤 Kousaku Shimada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:46
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/008; F02D41/30; F02D41/32; F02D41/38; F02D2041/389; F02D2200/00; F02D2200/02; F02D2200/06; F02D2200/0602; F02D2200/0604
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
109 words
An air/fuel ratio control apparatus for a direct injection multi-cylinder engine, comprising: injection amount calculation means for calculating a reference fuel injection amount used as a reference amount for determining a fuel injection amount into each of said cylinders, corresponding to operational states of said engine; actual injection amount estimation means for estimating an actual injection amount into each cylinder, based on an integration value of fuel pressure changes during a period of injecting fuel into at least one of said cylinders; and injection amount correction means for correcting said reference fuel injection amount calculated by said injection amount calculation means, based on said estimated actual fuel injection amount.
Claim 2
Dependent Claim
109 words
An air/fuel ratio control apparatus for a direct injection multi-cylinder engine, comprising: injection amount calculation means for calculating a reference fuel injection amount used as a reference amount for determining a fuel injection amount into each of said cylinders, corresponding to operational states of said engine; actual injection amount estimation means for estimating an actual injection amount into each cylinder, based on an integration value of fuel pressure changes during a period of injecting fuel into at least one of said cylinders; and injection amount correction means for correcting said reference fuel injection amount calculated by said injection amount calculation means, based on said estimated actual fuel injection amount.
Claim 3
Dependent Claim
93 words
An air/fuel ratio control apparatus for a direct injection multi-cylinder engine according to claim 1, wherein said actual injection amount estimation means estimates said actual fuel amount into each cylinder, based on the integration value of fuel pressure changes during a period of injecting fuel into said corresponding cylinder, and said injection amount correction means corrects said reference fuel injection amount calculated by said injection amount calculation means, based on said actual fuel injection amount estimated for said corresponding cylinder, in order to determine an injection fuel injection amount particular to each cylinder.
Claim 4
Dependent Claim
65 words
An air/fuel ratio control apparatus for a direct injection multi-cylinder engine according to claim 1, wherein said actual injection amount estimation means estimates said actual fuel injection amount into each cylinder, by searching a map in which an actual fuel injection amount is expressed by two variables of a peak value and an integration value of fuel pressure changes generated by only an fuel injection.
Claim 5
Dependent Claim
41 words
An air/fuel ratio control apparatus for a direct injection multi-cylinder engine according to claim 1, wherein said estimated actual fuel injection amount is obtained by averaging a plurality of actual fuel injection amounts estimated for a plurality times of fuel injections.
Claim 6
Dependent Claim
29 words
An air/fuel ratio control apparatus for a direct injection multi-cylinder engine according to claim 1, wherein said estimated actual fuel injection amount is calculated at every predetermined sampling period.
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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) | 2001-03-30 | 2001-09-29 | 2002-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-03-30 | 2005-09-29 | 2006-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-03-30 | 2009-09-29 | 2010-03-31 | $7700.00 | Window Closed / Lapsed |