Patent US4967727A successfully refreshed from Google Patents.
US4967727A
Expired / Lapsed
US
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Fuel controller for an internal combustion engine
Assignee: Mitsubishi Electric Corp
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Filing: 1989-08-16
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Granted: 1990-11-06
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Expires: 2009-08-16
Abstract
Abstract A fuel controller for an internal combustion engine has a microprocessor which calculates the air intake rate per cylinder per suction stroke of the engine. The microprocessor detects misfiring when the air intake rate undergoes a large increase, due to a fall in enginie rotational speed caused by misfiring. The microprocessor prevents the fuel injector of a misfiring cylinder from supplying fuel to the misfiring cylinder.
Inventors
- 👤 Toshihisa Takahashi
- 👤 Masanobu Uchinami
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:19
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/24; F02D41/26; F02D41/266; F02D41/22; G; G01; G01M; G01M15/00; G01M15/04; G01M15/042
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
95 words
A fuel controller for an internal combustion engine having a plurality of cylinders and a plurality of fuel injectors which supply fuel to the cylinders, comprising: measuring means for measuring the amount of intake air Q/N per cylinder per a prescribed number of suction strokes of the engine; misfiring sensing means for sensing a misfiring cylinder based on changes in the amount of intake air Q/N measured by said measuring means; and fuel supply cut-off means for cutting off the supply of fuel to a misfiring cylinder which is sensed by said misfiring sensing means.
Claim 2
Dependent Claim
95 words
A fuel controller for an internal combustion engine having a plurality of cylinders and a plurality of fuel injectors which supply fuel to the cylinders, comprising: measuring means for measuring the amount of intake air Q/N per cylinder per a prescribed number of suction strokes of the engine; misfiring sensing means for sensing a misfiring cylinder based on changes in the amount of intake air Q/N measured by said measuring means; and fuel supply cut-off means for cutting off the supply of fuel to a misfiring cylinder which is sensed by said misfiring sensing means.
Claim 3
Dependent Claim
81 words
A fuel controller as claimed in claim 1, wherein said measuring means comprises: air flow sensing means for generating a signal corresponding to the air flow rate Q into the engine; crank angle sensing means for generating an output signal at prescribed rotational angles of the engine; and calculating means responsive to said air flow sensing means and said crank angle sensing means for calculating the air intake Q/N per cylinder per a prescribed number of suction strokes of the engine.
Claim 4
Dependent Claim
61 words
A fuel controller as claimed in claim 1, wherein said misfiring sensing means comprises: means for calculating the change ΔQ/N in the air intake Q/N between successive power strokes of the engine for each cylinder; and means for determining when the absolute value E of the difference E between ΔQ/N for two of the cylinders is greater than a prescribed amount.
Claim 5
Dependent Claim
61 words
A fuel controller as claimed in claim 1, wherein said misfiring sensing means comprises: means for calculating the change ΔQ/N in the air intake Q/N between successive power strokes of the engine for each cylinder; and means for determining when the absolute value E of the difference E between ΔQ/N for two of the cylinders is greater than a prescribed percent.
Claim 6
Independent Claim
63 words
A method for controlling the fuel supply to an internal combustion engine having a plurality of cylinders and a fuel injector associated with each cylinder, comprising: measuring the amount of intake air Q/N per cylinder per suction stroke of the engine; detecting a misfiring cylinder based on the change ΔQ/N between measurements; and cutting off the supply of fuel to a misfiring cylinder.
Claim 7
Independent Claim
63 words
A method for controlling the fuel supply to an internal combustion engine having a plurality of cylinders and a fuel injector associated with each cylinder, comprising: measuring the amount of intake air Q/N per cylinder per suction stroke of the engine; detecting a misfiring cylinder based on the change ΔQ/N between measurements; and cutting off the supply of fuel to a misfiring cylinder.
Claim 8
Dependent Claim
73 words
A method as claimed in claim 5, wherein the step of detecting a misfiring cylinder comprises: determining the change ΔQ/N between measurements Q/N corresponding to consecutive power strokes of the engine; determining the difference E between a plurality of the changes ΔQ/N; comparing the absolute value E of the difference E with a prescribed value; and determining that a cylinder has misfired if the absolute value |E| is larger than the prescribed value.
References Cited (Backward Citations)
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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) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |