US5035225A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection control apparatus of internal combustion engine
Assignee: Toyota Motor Corp
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Filing: 1990-09-04
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Granted: 1991-07-30
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Expires: 2010-09-04
Abstract
Abstract A fuel injection control apparatus which controls the regular fuel injection amount based on a control law determined in accordance with a fuel dynamic model showing the dynamics of fuel flowing into an engine cylinder using as state variables the amount of fuel sticking to the walls of the intake passage and the amount of fuel evaporating in the intake passage. During deceleration operation, the regular fuel injection is stopped, the control law correction fuel injection amount is determined from the parameter values of the fuel dynamic model, the true values of the rate of fuel sticking to the walls of the intake passage and the rate of remainder of sticking fuel, which are parameters of the fuel dynamic model, are identified based on the amount of fuel injection, the amount of air flowing into the cylinder, and the air-fuel ratio, and the control law is corrected based on the results of the identification.
Inventors
- 👤 Masashi Mizukoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 01:04
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/02; F02D41/04; F02D41/047
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
214 words
A fuel injection control apparatus of an internal combustion engine having an intake passage, comprising: a fuel injector for injecting fuel in the intake passage; fuel injection amount calculation means for calculating the regular fuel injection amount to be injected from the fuel injector based on a control law determined in accordance with a fuel dynamic model expressing the dynamics of the fuel flowing into a cylinder of the engine; fuel injection stopping means for stopping the regular fuel injection based on the calculation by said regular fuel injection amount calculation means; control law correction fuel injection means for performing control law correction injection during the stoppage of the regular fuel injection; fuel sticking rate calculation means for calculating the rate of sticking of the control law correction injected fuel to the walls of the intake passage based on the amount of control law correction fuel injected during the stoppage of the regular fuel injection, amount of air flowing into the cylinder, and the air-fuel ratio of the air-fuel mixture flowing into the cylinder; and correction means for correcting the control law with respect to the amount of injected fuel to be supplied to the engine and making the air-fuel ratio a predetermined air-fuel ratio based on the calculated rate of sticking of fuel.
Claim 2
Dependent Claim
214 words
A fuel injection control apparatus of an internal combustion engine having an intake passage, comprising: a fuel injector for injecting fuel in the intake passage; fuel injection amount calculation means for calculating the regular fuel injection amount to be injected from the fuel injector based on a control law determined in accordance with a fuel dynamic model expressing the dynamics of the fuel flowing into a cylinder of the engine; fuel injection stopping means for stopping the regular fuel injection based on the calculation by said regular fuel injection amount calculation means; control law correction fuel injection means for performing control law correction injection during the stoppage of the regular fuel injection; fuel sticking rate calculation means for calculating the rate of sticking of the control law correction injected fuel to the walls of the intake passage based on the amount of control law correction fuel injected during the stoppage of the regular fuel injection, amount of air flowing into the cylinder, and the air-fuel ratio of the air-fuel mixture flowing into the cylinder; and correction means for correcting the control law with respect to the amount of injected fuel to be supplied to the engine and making the air-fuel ratio a predetermined air-fuel ratio based on the calculated rate of sticking of fuel.
Claim 3
Dependent Claim
43 words
A fuel injection control apparatus as set forth in claim 1, wherein the fuel dynamic model uses as the state variables the amount of fuel sticking to the walls of the intake passage and the amount of evaporated fuel in the intake passage.
Claim 4
Dependent Claim
175 words
A fuel injection control apparatus as set forth in claim 1, wherein the fuel dynamic model may be expressed by the following equation: ##EQU7## where, fw is the amount of fuel sticking to the walls of the intake passage, fv is the amount of fuel vaporizing in the intake passage, fi is the amount of fuel injected, Vfw is the amount of fuel evaporating from the walls of the intake passage, fc is the amount of fuel flowing into the cylinder, P is the model parameter of the rate of remainder of sticking fuel at the time of design, ΔP is the error between the model parameter of the rate of remainder of the sticking fuel at the time of design and the true value, R is the model parameter of the rate of sticking to the walls at the time of design; ΔR is the error between the model parameter of the rate of sticking to the walls at the time of design and the learned value, and Q, S, and D are constants.
Claim 5
Dependent Claim
26 words
A fuel injection control apparatus as set forth in claim 1, wherein the control law is calculated by an optimum regulator of the fuel dynamic model.
Claim 6
Dependent Claim
46 words
A fuel injection control apparatus as set forth in claim 1, which is provided with deceleration operation detection means for detecting the deceleration operation of the engine, the fuel injection stopping means stopping the regular fuel injection when the deceleration operation detection means detects deceleration operation.
Claim 7
Dependent Claim
47 words
A fuel injection control apparatus as set forth in claim 5, wherein the deceleration operation detection means judges that the state is of a deceleration operation when a throttle valve is in an idling position and the engine rotational speed is higher than a predetermined rotational speed.
Claim 8
Dependent Claim
38 words
A fuel injection control apparatus as set forth in claim 1, wherein the control law correction fuel injection means performs the control law correction fuel injection after the fuel sticking to the walls of the intake passage disappears.
Claim 9
Dependent Claim
41 words
A fuel injection control apparatus as set forth in claim 1, wherein the control law correction fuel injection means performs the control law correction fuel injection after the elapse of a predetermined time from the stopping of the regular fuel injection.
Claim 10
Dependent Claim
31 words
A fuel injection control apparatus as set forth in claim 1, wherein the control law correction fuel injection means performs the control law correction fuel injection repeatedly at predetermined time intervals.
Claim 11
Dependent Claim
84 words
A fuel injection control apparatus as set forth in claim 9, wherein when the air-fuel ratio after the previous control law correction fuel injection is rich, the learned value of the rate of fuel sticking to the walls of the intake passage at the time of execution of the previous control law correction fuel injection is decreased and when the air-fuel ratio is lean, learned value of the fuel sticking rate is increased, thereby determining the learned value of the current fuel sticking rate.
Claim 12
Dependent Claim
71 words
A fuel injection control apparatus as set forth in claim 10, wherein the control law correction fuel injection amount is determined by the following equation: TAU=TAU0/(1-R.sub.NOW) where, TAU0 is the amount of fuel for making the air-fuel ratio the stoichiometric air-fuel ratio and R NOW is the learned value of the rate of fuel sticking to the walls of the intake passage used for the current control law correction fuel injection.
Claim 13
Dependent Claim
63 words
A fuel injection control apparatus as set forth in claim 11, wherein the amount of fuel sticking to the walls of the intake passage due to the control law correction fuel injection is expressed as the product of the control law correction fuel injection amount and the learned value of the rate of fuel sticking to the walls of the intake passage currently.
Claim 14
Dependent Claim
72 words
A fuel injection control apparatus as set forth in claim 10, wherein when the air-fuel ratio inverts due to the execution of the control law correction fuel injection, the true value of the rate of sticking of fuel to the walls of the intake passage is calculated as the arithmetical mean value of the learned values of the rate of sticking of fuel before and after the inversion of the air-fuel ratio.
Claim 15
Dependent Claim
44 words
A fuel injection control apparatus as set forth in claim 13, which is provided with acceleration operation state detection means which detects an acceleration operation state of an engine, the learned value of the rate of remainder of sticking fuel being updated during acceleration.
Claim 16
Dependent Claim
56 words
A fuel injection control apparatus as set forth in claim 14, wherein when an acceleration operation state is detected by the acceleration operation state detection means within a predetermined time after the updating of the learned value of the fuel sticking rate, the learned value of the rate of remainder of the sticking fuel is updated.
Claim 17
Dependent Claim
36 words
A fuel injection control apparatus as set forth in claim 14, wherein the acceleration operation state detection means detects the acceleration state when the rate of increase of an intake pipe pressure exceeds a predetermined value.
Claim 18
Dependent Claim
112 words
A fuel injection control apparatus as set forth in claim 14, wherein the learned value of the rate of remainder of the sticking fuel is changed in accordance with the difference in the time in which the air-fuel ratio is rich and the time in which the air-fuel ratio is lean in a predetermined time after the acceleration operation state is detected by the acceleration detection means within a predetermined time after the updating of the learned value of the fuel sticking rate, i.e., is increased when the difference in time is larger than a first predetermined value and decreased when the difference in time is smaller than a second predetermined value.
Claim 19
Dependent Claim
33 words
A fuel injection control apparatus as set forth in claim 13, wherein the correction means corrects the parameters of the fuel dynamic model based on the true value of the fuel sticking rate.
Claim 20
Dependent Claim
36 words
A fuel injection control apparatus as set forth in claim 17, wherein the correction means corrects the parameters of the fuel dynamic model based on the learned value of the rate of remainder of sticking fuel.
Claim 21
Dependent Claim
61 words
A fuel injection control apparatus as set forth in claim 3, wherein when the amount of fuel sticking to the walls, calculated by the fuel dynamic model, becomes negative, the amount of fuel sticking to the walls is made zero and amount of fuel evaporation from the intake passage and the amount of evaporated fuel in the intake passage are corrected.
Claim 22
Dependent Claim
53 words
A fuel injection control apparatus as set forth in claim 13, wherein the control law correction fuel injection means performs at least two injections of control law correction fuel after the fuel sticking to the walls of the intake passage again disappears after calculation of the true value of the fuel sticking rate.
Claim 23
Dependent Claim
87 words
A fuel injection control apparatus as set forth in claim 20, wherein when the air-fuel ratio after the previous control law correction fuel injection is rich, the learned value of the rate of remainder of sticking fuel at the time of execution of the previous control law correction fuel injection is decreased and when the air-fuel ratio is lean, the learned value of the rate of remainder of the sticking fuel is increased, thereby determining the learned value of the current rate of remainder of sticking fuel.
Claim 24
Dependent Claim
94 words
A fuel injection control apparatus as set forth in claim 21, where the control law correction fuel injection amount is determined by the following equation: TAU=TAU0/(1-P.sub.NOW ·R.sub.CR) where TAU0 is the amount of fuel for making the air-fuel ratio the stoichiometric air-fuel ratio, P NOW is the learned value of the rate of remainder of the fuel sticking to the walls of the intake passage used for the current control law correction fuel injection, and R CR is the true value of the rate of fuel sticking to the walls of the intake passage.
Claim 25
Dependent Claim
75 words
A fuel injection control apparatus as set forth in claim 22, wherein the amount of fuel sticking to the walls of the intake passage due to the control law correction fuel injection is determined from the control law correction fuel injection amount, the learned value of the rate of remainder of the fuel sticking to the walls currently, and the true value of the rate of fuel sticking to the walls of the intake passage.
Claim 26
Dependent Claim
73 words
A fuel injection control apparatus as set forth in claim 21, wherein when the air-fuel ratio inverts due to execution of two injection of the control law correction fuel, the true value of the rate of remainder of the fuel sticking to the walls is calculated as the arithmetical mean of the learned values of the rate of remainder of fuel sticking to the walls before and after inversion of the air-fuel ratio.
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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) | 1994-07-29 | 1995-01-28 | 1995-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-29 | 1999-01-28 | 1999-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-29 | 2003-01-28 | 2003-07-30 | $7700.00 | Window Closed / Lapsed |