← Back to Patent Explorer
US5214958A Expired / Lapsed US ⏱️ 0.0 years remaining

Misfiring detecting apparatus for an internal combustion device

Assignee: Mitsubishi Electric Corp
•
Filing: 1992-02-13
•
Granted: 1993-06-01
•
Expires: 2012-02-13
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An apparatus for defecting occurrence of misfiring in an internal combustion engine with improved reliability. A change in an angular velocity of a crankshaft of the engine and a change in the output of an air/fuel ratio sensor are monitored. Only when both changes indicate occurrence of misfiring independently from each other, it is decided that misfiring in the cylinder has taken place. Reliability in misfiring detection is improved by using the results obtained through at least two mutually different types of misfiring detections.

Inventors

  • 👤 Masanori Inada
  • 👤 Akira Demizu
  • 👤 Akihiro Nakagawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 02:28
CPC Classifications
G; G01; G01M; G01M15/00; G01M15/04; G01M15/042; G01M15/05; G01M15/10; G01M15/102; G01M15/11

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 74 words
An apparatus for detecting occurrence of misfiring in an internal combustion engine, comprising: at least two misfiring detecting means for detecting misfiring independently of each other, said misfiring detecting means operating based on mutually different detection principles, respectively; and means operatively coupled to the outputs of said at least two misfiring detecting means for deciding occurrence of misfiring only when both outputs of said at least two misfiring detecting means indicate occurrence of misfiring.
Claim 2
Independent Claim 74 words
An apparatus for detecting occurrence of misfiring in an internal combustion engine, comprising: at least two misfiring detecting means for detecting misfiring independently of each other, said misfiring detecting means operating based on mutually different detection principles, respectively; and means operatively coupled to the outputs of said at least two misfiring detecting means for deciding occurrence of misfiring only when both outputs of said at least two misfiring detecting means indicate occurrence of misfiring.
Claim 3
Independent Claim 101 words
An apparatus for detecting occurrence of misfiring in an internal combustion engine, comprising: a plurality of sensors for sensing engine operating parameters which differ from one another and which represent a combustion state of said engine; a plurality of misfiring detecting means provided in association with said sensors, respectively, for processing output signals of said sensors to thereby detect occurrence of misfiring in the engine independently of one another; and decision means connected to the outputs of said misfiring detecting means for deciding occurrence of misfiring when at least two of said misfiring detecting means detect occurrence of misfiring substantially simultaneously.
Claim 4
Independent Claim 101 words
An apparatus for detecting occurrence of misfiring in an internal combustion engine, comprising: a plurality of sensors for sensing engine operating parameters which differ from one another and which represent a combustion state of said engine; a plurality of misfiring detecting means provided in association with said sensors, respectively, for processing output signals of said sensors to thereby detect occurrence of misfiring in the engine independently of one another; and decision means connected to the outputs of said misfiring detecting means for deciding occurrence of misfiring when at least two of said misfiring detecting means detect occurrence of misfiring substantially simultaneously.
Claim 5
Dependent Claim 38 words
A misfiring detecting apparatus according to claim 2, wherein said misfiring detecting means comprise a first means for detecting occurrence of misfiring on the basis of a change in an angular velocity of a crankshaft of said engine.
Claim 6
Dependent Claim 69 words
A misfiring detecting apparatus according to claim 3, wherein said first means calculates a time ratio between a time taken for said crankshaft to rotate a first predetermined angular distance before a predetermined angular reference position and a time taken for said crankshaft to rotate a second predetermined angular distance after said predetermined angular reference position, and determines occurrence of misfiring when said time ratio exceeds a predetermined value.
Claim 7
Dependent Claim 41 words
A misfiring detecting apparatus according to claim 3, wherein said misfiring detecting means further comprise a second means which detects occurrence of misfiring on the basis of a change in an air/fuel ratio of an exhaust gas discharged from said engine.
Claim 8
Dependent Claim 36 words
A misfiring detecting apparatus according to claim 5, wherein said misfiring detecting means further comprise a third means for detecting occurrence of misfiring on the basis of a change in the pressure within an engine cylinder.
Claim 9
Dependent Claim 29 words
A misfiring detecting apparatus according to claim 2, wherein said decision means comprises an AND circuit for performing logical decision from the outputs of said plural misfiring detecting means.

References Cited (Backward Citations)

US3924457A Cited
JPS5819532A Cited
US4700563A Cited
US4887574A Cited
JPS63263241A Cited
JPS6472728A Cited
US5168859A Cited
US5105657A Cited
US5044195A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-05-31 1996-11-30 1997-06-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-05-31 2000-11-30 2001-06-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-05-31 2004-11-30 2005-06-01 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag