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US5390641A Expired / Lapsed US ⏱️ 0.0 years remaining

Fuel injection system for internal combustion engine

Assignee: Denso Corp
•
Filing: 1993-12-08
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Granted: 1995-02-21
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Expires: 2013-12-08
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Abstract

Abstract A fuel injection control system for an internal combustion engine which can eliminate lean misfiring and rich misfiring at asynchronous injection and exhausting of non-combustioned HC. When the asynchronous injection is performed at engine cranking or at acceleration, a judgement is made as to whether the injected fuel will be divided by closure of an intake valve. When division is not detected, fuel injection is performed in normal manner. When division is detected, rate of the fuel division is computed. As a result of computation, fuel injection is performed when judgement is made that a predetermined amount of the injected fuel will be introduced into the cylinder. Furthermore, the amount of fuel not introduced into the cylinder is computed to reduce a corresponding amount from a fuel injection amount for the next cycle. On the other hand, when judgement is made that the predetermined amount of fuel will not be introduced into the cylinder, fuel injection does not take place.

Inventors

  • 👤 Masakazu Yamada
  • 👤 Masakazu Ninomiya
  • 👤 Yasuo Sagisaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 20:12
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/02; F02D41/04; F02D41/06; F02D41/062; F02D41/10; F02D41/105; F02D41/30; F02D41/32; F02D41/34; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 224 words
A fuel injection control system for an internal combustion engine comprising: crank angle detecting means for detecting a crank angle; synchronous-injection means for performing synchronous injection of a fuel into an intake manifold for each cylinder in synchronism with the crank angle detected by said crank angle detecting means; intake valve closure timing detecting means for detecting a crank angle corresponding to closure of an intake valve of each cylinder of the engine, in advance; asynchronous injection means for performing asynchronous injection of fuel into the intake manifold of each cylinder upon at least one of engine starting state and acceleration state; asynchronous injection crank angle computing means for determining crank angles at initiation of an asynchronous injection of fuel and termination of the asynchronous injection before initiation of said asynchronous injection to be performed by said asynchronous injection means; injected fuel division checking means for checking whether fuel amount of the asynchronous injection performed by said asynchronous injection means is divided or not by the closure of the intake valve caused at the crank angle detected by said intake valve closure timing detecting means in advance and said crank angles determined by said asynchronous injection crank angle computing means; and first fuel injection control means for inhibiting fuel injection when said injected fuel division checking means detects a division of the fuel amount.
Claim 2
Dependent Claim 224 words
A fuel injection control system for an internal combustion engine comprising: crank angle detecting means for detecting a crank angle; synchronous-injection means for performing synchronous injection of a fuel into an intake manifold for each cylinder in synchronism with the crank angle detected by said crank angle detecting means; intake valve closure timing detecting means for detecting a crank angle corresponding to closure of an intake valve of each cylinder of the engine, in advance; asynchronous injection means for performing asynchronous injection of fuel into the intake manifold of each cylinder upon at least one of engine starting state and acceleration state; asynchronous injection crank angle computing means for determining crank angles at initiation of an asynchronous injection of fuel and termination of the asynchronous injection before initiation of said asynchronous injection to be performed by said asynchronous injection means; injected fuel division checking means for checking whether fuel amount of the asynchronous injection performed by said asynchronous injection means is divided or not by the closure of the intake valve caused at the crank angle detected by said intake valve closure timing detecting means in advance and said crank angles determined by said asynchronous injection crank angle computing means; and first fuel injection control means for inhibiting fuel injection when said injected fuel division checking means detects a division of the fuel amount.
Claim 3
Dependent Claim 76 words
A fuel injection control system according to claim 1, further comprising combustion judging means for judging whether combustion is possible with the divided fuel amount when a division of the injected fuel is detected by said injected fuel division checking means, and releasing said first fuel injection control means from inhibiting of fuel injection in order to allow fuel injection when judging combustion as possible to take place with the divided fraction of the injected fuel.
Claim 4
Dependent Claim 69 words
A fuel injection control system according to claim 2, further comprising: residual fuel amount computing means computing a residual amount of fuel possibly residing in the intake manifold after possible combustion of fuel injection is performed; and second fuel injection control means for controlling said synchronous injection means to perform a next cycle synchronous injection of fuel amount reduced by a corresponding amount to the computed residual fuel amount.
Claim 5
Dependent Claim 77 words
A fuel injection control system according to claim 1, including engine state detection means for detecting engine starting state/engine normal operating state; and means, responsive to said engine state detection means, for computing an amount of fuel TAUS for synchronous injection in a detected engine starting state/an amount of fuel for synchronous injection in a detected engine normal operating state by means of detecting engine control parameters of cooling water temperature, battery voltage and engine speed Ne.
Claim 6
Dependent Claim 64 words
A fuel injection control system according to claim 4, wherein said asynchronous injection means includes memory means for storing a crank angle XCRNK of each cylinder; and means for detecting which of predetermined ranges of crank angles the stored crank angle is calculated in and designating a cylinder to have an asynchronous injection performed with the detection of one of the crank angle ranges.
Claim 7
Dependent Claim 55 words
A fuel injection control system according to claim 5, wherein said asynchronous injection crank angle computing means includes means for determining a timing of crank angle SCRNK for the initiation of an asynchronous injection by computing ##EQU3## and determining a timing of crank angle YCRNK for the termination of the asynchronous injection by computing ##EQU4##
Claim 8
Dependent Claim 49 words
A fuel injection control system according to claim 6, wherein said injected fuel division checking means includes means for prestoring a crank angle position ZCRNK#i for closure of each cylinder; means for adjusting timing of the intake valve closure of a predetermined cylinder in response to the computed SCRNK.
Claim 9
Dependent Claim 31 words
A fuel injection control system according to claim 7, wherein said combustion judging means is adapted to judge the combustion as possible by confirming a relation ##EQU5## with each cylinder #i.
Claim 10
Dependent Claim 36 words
A fuel injection control system according to claim 8, wherein said second fuel injection control means is adapted to reduce a fuel amount TAUS computed for the next cycle sync injection by an amount of ##EQU6##
Claim 11
Dependent Claim 51 words
A fuel injection control system according to claim 8, wherein said second fuel injection control means includes means for reducing a fuel amount TAUS/TAU computed for synchronous injection by a corresponding amount to the computed residual amount of fuel in response to each of predetermined crank angles (30°, 270°, 450°, 630°).
Claim 12
Dependent Claim 79 words
A fuel injection control system according to claim 3, wherein said asynchronous injection crank angle computing means includes means for computing amount of fuel TAUAC for asynchronous injection with detection of intake air pressure and cooling water temperature under engine accelerating condition; and means for detecting a crank angle SCRNK corresponding to a predetermined increment in intake air pressure in order for the initiation of asynchronous injection and determining a crank angle YCRNK by computing a relation YCRNK= ##EQU7##
Claim 13
Dependent Claim 40 words
A fuel injection control system according to claim 11, wherein said injected fuel division checking means is adapted to check if SCRNK≦(ZCRNK#i-6Ne/100)≦YCRNK, where ZCRNK#i indicates a predetermined crank angle corresponding to the closure of an optional cylinder #i intake valve.
Claim 14
Dependent Claim 57 words
A fuel injection control system according to claim 12, wherein said first fuel injection control means includes means for checking if ##EQU8## in order to judge whether combustion is possible with the divided fuel amount; and said second fuel injection control means includes means for determining the residual amount of fuel YZ#i by computing a relation YZ#i=YCRNK-ZCRNK#i.

References Cited (Backward Citations)

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JPS60111042A Cited
JPS60240875A Cited
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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) 1998-02-20 1998-08-22 1999-02-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-02-20 2002-08-22 2003-02-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-02-20 2006-08-22 2007-02-21 $7700.00 Window Closed / Lapsed

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