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US5586524A Expired / Lapsed US ⏱️ 0.0 years remaining

Fuel injection control system for internal combustion engine

Assignee: Yamaha Marine Co Ltd
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Filing: 1994-09-01
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Granted: 1996-12-24
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Expires: 2014-09-01
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Abstract

Abstract A fuel injection control system accurately determines the amount of fuel to be injected by compensating the measured crankcase pressure in view of various conditions including intake air condition, effects of exhaust gas pressure by other cylinder and others, with use of one pressure sensor. The fuel injection control system includes a pressure sensor installed in a cylinder of the engine for detecting crankcase pressure, a fuel injector for injecting fuel to the engine on the basis of the crankcase pressure detected by the pressure sensor, and a device for compensating the amount of fuel injected from the fuel injector depending on the condition of intake air in the crankcase. Another aspect of the system additionally includes controlling timing for detecting the crankcase pressure by the pressure sensor depending on the rotation rate of the engine. Further aspect of the system additionally include determining the amount of fuel to be injected to the engine by incorporating a compensation factor in the crankcase pressure obtained by the pressure sensor wherein the compensation factor includes an effect caused by exhaust gas pressure in other cylinders.

Inventors

  • 👤 Kimihiro Nonaka
  • 👤 Hiroaki Ohtani

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 06:18
CPC Classifications
F; F02; F02D; F02D35/00; F02D35/02; F02D35/023; F02B; F02B33/00; F02B33/02; F02B33/04; F02D41/00; F02D41/02; F02D41/14; F02D41/1438; F02D41/1444; F02D41/30; F02D41/32; F02B75/00; F02B75/02; F02B2075/022; F02B2075/025; F02D2200/00; F02D2200/02; F02D2200/04; F02D2200/0418; F02D2400/00; F02D2400/04

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 109 words
A fuel injection control system for a two-cycle internal combustion engine, comprising a pressure sensor installed in a cylinder of said engine for detecting crankcase pressure at the time of scavenge opening and scavenge closing to obtain a tentative intake air amount, a fuel injector for injecting fuel to said engine on the basis of said crankcase pressure detected by said pressure sensor, means for compensating the amount of fuel injected from said fuel injector in response to the condition of intake air in said crankcase to obtain a compensation factor to be multiplied by said tentative air amount to determine a true amount of fuel to be injected.
Claim 2
Dependent Claim 109 words
A fuel injection control system for a two-cycle internal combustion engine, comprising a pressure sensor installed in a cylinder of said engine for detecting crankcase pressure at the time of scavenge opening and scavenge closing to obtain a tentative intake air amount, a fuel injector for injecting fuel to said engine on the basis of said crankcase pressure detected by said pressure sensor, means for compensating the amount of fuel injected from said fuel injector in response to the condition of intake air in said crankcase to obtain a compensation factor to be multiplied by said tentative air amount to determine a true amount of fuel to be injected.
Claim 3
Dependent Claim 31 words
A fuel injection control system as defined in claim 1, wherein, said condition of said intake air includes temperature, humidity of said intake air and fuel volatility in said intake air.
Claim 4
Dependent Claim 38 words
A fuel injection control system as defined in claim 1, wherein said pressure sensor comprises; an inner diaphragm and an outer diaphragm mounted on a sensor body; silicon oil filled between said inner diaphragm and said outer diaphragm.
Claim 5
Dependent Claim 41 words
A fuel injection control system as defined in claim 3, wherein said pressure sensor is positioned to be protected by a skirt of a piston in said cylinder from a backfire in said cylinder and in other cylinders of said engine.
Claim 6
Dependent Claim 68 words
A fuel injection control system for an internal combustion engine, comprising a pressure sensor installed in a cylinder of said engine for detecting crankcase pressure, a fuel injector for injecting fuel to said engine on the basis of said crankcase pressure detected by said pressure sensor, means for controlling the timing of detecting said crankcase pressure by said pressure sensor depending on the rotation rate of said engine.
Claim 7
Dependent Claim 68 words
A fuel injection control system for an internal combustion engine, comprising a pressure sensor installed in a cylinder of said engine for detecting crankcase pressure, a fuel injector for injecting fuel to said engine on the basis of said crankcase pressure detected by said pressure sensor, means for controlling the timing of detecting said crankcase pressure by said pressure sensor depending on the rotation rate of said engine.
Claim 8
Dependent Claim 79 words
A fuel injection control system as defined in claim 5, wherein said crankcase pressure is measured by said pressure sensor at the timing of scavenge opening and at the timing of scavenge opening, said means for controlling said detection timing controls said timing such that said timing of measurement upon scavenge opening is held constant while said timing of measurement upon said scavenge closing is delayed in accordance with the the increase of said rotation rate of said engine.
Claim 9
Dependent Claim 89 words
A fuel injection control system for an internal combustion engine, comprising a pressure sensor installed in a cylinder of said engine for detecting crankcase pressure, a fuel injector for injecting fuel to said engine on the basis of said crankcase pressure detected by said pressure sensor, means for determining the amount of fuel to be injected to said engine by incorporating a compensation factor in said crankcase pressure obtained by said pressure sensor, said compensation factor including compensation for the effect caused by exhaust gas pressure in other cylinders.
Claim 10
Dependent Claim 89 words
A fuel injection control system for an internal combustion engine, comprising a pressure sensor installed in a cylinder of said engine for detecting crankcase pressure, a fuel injector for injecting fuel to said engine on the basis of said crankcase pressure detected by said pressure sensor, means for determining the amount of fuel to be injected to said engine by incorporating a compensation factor in said crankcase pressure obtained by said pressure sensor, said compensation factor including compensation for the effect caused by exhaust gas pressure in other cylinders.
Claim 11
Dependent Claim 23 words
A fuel injection control system as defined in claim 7, wherein said compensation factor varies depending on the rotation rate of said engine.
Claim 12
Dependent Claim 45 words
A fuel injection control system as defined in claim 7, wherein said system determines crankcase pressure in all the cylinders in said engine on the basis of said crankcase pressure sensed by said pressure sensor installed in only one cylinder by utilizing said compensation factor.
Claim 13
Dependent Claim 41 words
A fuel injection control system as defined in claim 8, wherein said system detects a misfire in other cylinders and compensates for effect caused by said misfire to determine a true amount of fuel to be injected by said fuel injector.
Claim 14
Dependent Claim 46 words
A fuel injection control system as defined in claim 7, wherein a substantial amount of said determined amount of fuel is injected determined from conditions, in the previous cycle of said engine and the remaining amount of fuel is determined by conditions in said present cycle.

References Cited (Backward Citations)

US4461260A Cited
US5127373A Cited
US5134984A Cited
US5284118A Cited
US5367998A Cited
US5329907A Cited
US5404843A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-12-24 2000-06-24 2000-12-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-12-24 2004-06-24 2004-12-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-12-24 2008-06-24 2008-12-24 $7700.00 Window Closed / Lapsed

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