CA1297968C - Engine control apparatus - Google Patents
Engine control apparatusInfo
- Publication number
- CA1297968C CA1297968C CA000561069A CA561069A CA1297968C CA 1297968 C CA1297968 C CA 1297968C CA 000561069 A CA000561069 A CA 000561069A CA 561069 A CA561069 A CA 561069A CA 1297968 C CA1297968 C CA 1297968C
- Authority
- CA
- Canada
- Prior art keywords
- engine
- correction amount
- sensor
- learned
- control apparatus
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000012937 correction Methods 0.000 claims abstract description 45
- 238000012935 Averaging Methods 0.000 claims abstract description 6
- 239000000446 fuel Substances 0.000 claims description 26
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 5
- 239000001301 oxygen Substances 0.000 claims description 4
- 229910052760 oxygen Inorganic materials 0.000 claims description 4
- 238000001514 detection method Methods 0.000 claims description 2
- 230000004044 response Effects 0.000 claims description 2
- 230000001276 controlling effect Effects 0.000 description 38
- 238000002347 injection Methods 0.000 description 11
- 239000007924 injection Substances 0.000 description 11
- 229940090044 injection Drugs 0.000 description 10
- WRRSFOZOETZUPG-FFHNEAJVSA-N (4r,4ar,7s,7ar,12bs)-9-methoxy-3-methyl-2,4,4a,7,7a,13-hexahydro-1h-4,12-methanobenzofuro[3,2-e]isoquinoline-7-ol;hydrate Chemical compound O.C([C@H]1[C@H](N(CC[C@@]112)C)C3)=C[C@H](O)[C@@H]1OC1=C2C3=CC=C1OC WRRSFOZOETZUPG-FFHNEAJVSA-N 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 238000002485 combustion reaction Methods 0.000 description 3
- 230000010354 integration Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 208000003251 Pruritus Diseases 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D33/00—Controlling delivery of fuel or combustion-air, not otherwise provided for
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
- F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
- F02D41/2425—Particular ways of programming the data
- F02D41/2429—Methods of calibrating or learning
- F02D41/2477—Methods of calibrating or learning characterised by the method used for learning
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
- F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
- F02D41/2425—Particular ways of programming the data
- F02D41/2429—Methods of calibrating or learning
- F02D41/2451—Methods of calibrating or learning characterised by what is learned or calibrated
- F02D41/2454—Learning of the air-fuel ratio control
Abstract
ABSTRACT OF THE DISCLOSURE
An engine control apparatus comprises a plurality of sensors for detecting the operation state of an engine, means for calculating, on the basis of signals produced from the sensors, a correction amount which corrects a predetermined controllable quantity, means for calculating a learned correction amount by averaging values of the correction amount by a reference occurrence frequency, means for calculating, under a predetermined condition, the learned correction amount by averaging values of the correction amount by an occurrence frequency which is smaller than the reference occurrence frequency, and means for correcting the controllable quantity in accordance with the correction amount and the learned correction amount.
An engine control apparatus comprises a plurality of sensors for detecting the operation state of an engine, means for calculating, on the basis of signals produced from the sensors, a correction amount which corrects a predetermined controllable quantity, means for calculating a learned correction amount by averaging values of the correction amount by a reference occurrence frequency, means for calculating, under a predetermined condition, the learned correction amount by averaging values of the correction amount by an occurrence frequency which is smaller than the reference occurrence frequency, and means for correcting the controllable quantity in accordance with the correction amount and the learned correction amount.
Description
~2~
This invention relates to an apparatus for controlling an engine such as an internal combustion engine and more particularly to an engine control apparatus having a learned controlling function.
An engine control apparatus having a learned controlling function is disclosed in, for example, JP-A~59-180048. As is clear from the disclosure of the above public literature, in the conventional engine control apparatus having the learned controlling func-tion, irreyularity in characteris-tics of the engine per se and irregularity and secular variation in character-istics of sensors adapted to detect the status of the engine are corrected using the learned controlling function and various controllable quantities such as for example air/fuel ratio and ignition timing can be con-trolled optimumly.
ln the conventional engine control apparatus as exemplified in the a:Eorementioned public literature, however, the control speed Eor learned controlling is unchangeable and it takes a long time to obtain optimum engine control through the learned controlling.
The control speed Eor learned controlling is desired to be high during a predetermined con~ition thereby placing the engine in optimumly controlled .
96~
1 condition through the learned controlling within a short period of time following the commencement of use by the user.
SUMMARY OF THE INVENTION
An object of this invention is to provide an engine control apparatus which can obtain, within a relatively short period of time, correction amounts for correcting irregularity in characteristics of the engine per se and irregularity in characteristics of various sensors so as to control the engine optimumly.
According to the invention, to accomplish theabove object, an engine control apparatus for controlling at least the fuel supply amount representative of the controllable quantities by fetching signals from the sensors adapted to detect the status of the engine comprises learned controlling means ~or controlling the controllable quantity on the basis of the signals from the sensors, and control speed chanyiny means for changing, under a predetermined condition, the control speed for the learned controlliny means to a value which is higher than a reference value.
~z97~ 8 1 In particular, the invention relates to an engine control apparatus comprising: a plurality o~ sensors for detecting selected states of an engine; first calculating means for calculating, on the basis of signals produced .~rom said sensors, a correction amount which corrects a prede-termined controllable quantity; second calculating means for calculating a learning correction amount by averaging values of said correction amount at a predetermined reference occurrence frequency of sampled co.rrection amount values;
means for controlling said second calculating means, in response to detection oE a predetermined condition, by changing the occurrence frequency at which sampled values of the correction amount are averaged to an occurrence frequency which is smaller than said predetermined reference occurrence fre~uency; and means for correcting said control-lable quantity in accordance with said correction amount and said learning correction amount.
With this construction, the control speed changing means sets, under the predetermined condition, the control speed for learned controlling to a higher value than the reEerence value so that the engine can be placed in optimumly controlle~ con~ition throu~h the learned controlling within a short period oE time - 2a -~g7~6~
1 following the commencement of use by the user. At the expiration of a predetermined period of time, the control speed for learned controlling is set to the reference value.
DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic block diagram showing an engine control apparatus according to an embodiment of the invention.
Figure 2 is a time chart showing a correction coefficient changing with the operation of the Fig. 1 apparatus.
Figure 3 is a time chart showing a change in the correction coefficient through learned controlling in the Fig. 1 apparatus.
Figure 4 illustrates a map of learned correc-tion coefficient data in a RAM obtained through learned controlling in the Fig. 1 apparatus.
Figure 5 is a flow chart showing the operation of the Fig. 1 apparatus.
Figure 6 i.s a time chart showing another example of a change in the correction coefEicient throuyh learned controlliny ;n the Fig. 1 apparatus.
DESCRIPTION OF' TEIE PREFERRED EMBODIMENT
An engine control apparatus according to a preferred embodiment of the invention will now be described with reference to Figs. 1 to 6.
s6a 1 Firstly, referring to Fig. 1, an engine 1 has an intake conduit 10 in which an intake air flow rate sensor 2 is disposed having an output terminal connected to a control console 3. Disposed near one end of the intake conduit 10 is an injector 6 for fuel injection to the engine 1, the injector 6 having an input terminal connected to the control console 3.
In an exhaust conduit 11 of the engine 1 is an oxygen (2) sensor 5 having an output terminal connected to the control console 3. In this embodiment, the pulse width for fuel injection to the engine 1 is controlled on the basis of a concentration of oxygen in exhaust gas which is detected by the 2 sensor 5.
A crank angle sensor 4 rotates in synchronism with the rotation of the engine 1 to produce an engine revolution number signal which is applied to the control console 3, and an odometer 7 is connected to the control console 3 to supply thereto a signal indicative of a running distance of a vehicle.
The engine control apparatus constructed as above operates as will be described below.
Where QA is -the intalce air amount which is calculated by the control console 3 on the basis of a flow rate signal measured by the intake air flow rate sensor 2, N is the engine revolution number (per unit time) which is calculated by the control console 3 on the basis of an engine revolution number signal in the form of pulses produced from the crank angle sensor 4 ~2~7~
1 each time the engine rotates a predetermined angle and _ is a constant, the control console 3 calculates the pulse width Tp for fuel injection in accordance with -the following equation:
Tp = k x QA/N _____ (1) The fuel injection amount based on the pulse width Tp for fuel injection as obtained from equation (1) is feedback controlled using a signal produced from the 2 sensor 5. More specifically, where ~ is the feedback correction coefficient and aL is the learned correction coefficient obtained through learned control-ling, the control console 3 comprised of a microcomputer calculates the corrected pulse width Ti for fuel injec-tion in accordance with the following equation:
Ti = Tp x (~ + ~L) ----- (2) The ultimate pulse width for fuel injection to the injector 6 is controlled pursuant to equation (2) The correction coefficient ~ in equ~tion (2) can he obtained through proportional integration control corresponding to the output s1gnal of the 2 sensor 5, as shown in Fig. 2. More particularly, when the air/
fuel ratio changes from "LEAN" to "RICH", for the purpose of rapid controlling, the proportional portion, ~79~S8 1 PR, is subtracted and thereafter the integration portion at the rate of IR is subtracted. Conversely, when the air/fuel ratio changes from "RICH" to "LEAN", for the purpose of rapid controlling, the proportional portion, PL, is added and thereafter the in-tegration portion at the rate of IL is added~
This conventionally available correction based on the correction coefficient ~ alone, however, fails to correct errors in controlling attributable to the difference in individuality of the engines per se of vehicles and manufacture errors (irregularity) or secular variation in the various sensors. ~ccordingly, it has hitherto been also practice to make correction by using the learned correction coefficient ~L obtained through learned controlling. The learned correction coefficient ~L is defined by an average of values of the correction coefficient ~.
Therefore, when the air/fuel ratio changes from fuel "RICH" to fuel "LEAN" or conversely from fuel "LEAN" to fuel "RICH", values of ~ are averaged to determine a value of ~L as shown in Fig. 3. The value f ~L ls -~L in this example. Values of the learned correction coefficient ~L are obtained in relation to various running states and stored in a RAM 3A of the control console 3, as shown in ~ig. 4.
In Fig. 4, data values of the learned correc-tion coef~icient ~L are related to the runnin~ state in which the engine speed becomes higher as the revolution ~7~
1 number N changes to the right on abscissa and the fuel becomes rich, i.e., the load on the engine becomes higher as ~he pulse width Tp for fuel injection changes upwards. Data values ~Ll to ~L24 stored in the RAM 3A
in relation to various operation or running states of the engine are not obtained by uniformly averaging values of ~. Specifically, data values ~L6, L7, ~Llo, 11' ~L14, ~L15, ~L18 and ~L19 on almost the central area in Fig. 4 are related to engine states which occur relatively frequently and can be obtained by averaging many (for example, ten) values of ~. But data values on the peripheral area (for example, ~Ll, ~L4, ~L21 and ~L24) are related to engine states which occur infre-quently and if these data values ~Li are to be deter-mined by the conventlonal method which is designed toaverage, for example, ten values of ~, these data values on the peripheral area will remain undetermined for a long time. When under this condition the engine states which are expected to occur infrequently occur, there results a problem that optimum engine controlling can not be performed by the conventional method.
To solve this problem, the present invention features in that, for example, for a small running distance attributed to a new car, in view of the fact that the new car has poor experience in learning, values of ~ are averaged by a relatively small number (for example, five) to determine data values ~Li, whereby data values ~Li on the entire area of the map of Fig. 4 ~2~6~
1 can be obtained within a relatively short period of time to meet controlling for any englne states. By using the thus obtained a and ~L, the air/fuel ratio can be controlled optimumly pursuant to equation (2).
Referring to Fig. 5, the operational procedure to this end will be described. In step 101, the intake air amount QA is calculated in accordance with a flow rate signal produced from the intake air flow rate sensor 2 and in step 102, the engine revolution number N is calculated in accordance with an engine revolution number signal produced from the crank angle sensor 4.
Subsequently, in s-tep 103, the pulse width Tp for fuel injection is calculated pursuant to equation (1) and in step 104, a signal produced from the 2 sensor 5 is fetched. In step 105, the correction coefficient is calculated on the basis of the signal of the 2 sensor 5 fetched in step 104 through the proportional integration controlling as previously described in connection with Fig. 2, in a manner well known by itself.
The procedure then proceeds to step 106 in which it is decided from a running distance signal produced frorn the odometer 7 whether the running distance of the vehicle is below I Km.
I the running distance of the vehi.cle is decided to be below I Km in step 106, the learned correction coefficient ~L is calculated, in step 108, pursuant to the following equation:
~.2~7g~
~ )/N2 = ~L ~~-~~ (3) 1 If the running distance of the vehicle is decided to exceed I Km in step 106, the learned correction coefficient ~L is calculated, in step 107, pursuant to the following equation:
~ )/Nl = ~L ~~~~~ (4) Since Nl in equation (4) is related to N2 in equation (3) by Nl >>N2, data values of the ].earned correction coefficient ~L can be calculated and deter-mined through learned controlling within a short period of time.
Finally, in step 109, the learned correction coefficient ~L determined pursuant to equation (3) or (4) and the correction coefficient ~ determined in step 105.are used to calculate the pulse width Ti for fuel injection pursuant to equation (2).
As described above, according to this embodi-ment oE the invention, the control speed ~or learned controlling is set to a higher vaJ.ue be~ore the vehicle reaches a predetermined running distance, thereby ensuring that the ai.r/fuel ratio can be controlled optimumly withi.n a short period of time following the commencement of use by the user.
9~;8 1 Fig. 6 shows another way to obtain the learned correction coefficient ~L through learned controlling.
In this example, values of ~ represented by ~(t), ~(t~ (t-n) are multiplied by desired weight coefficients ko~ kl, ----- kn, respectively, to calculate the learned correction coefficient ~L
pursuant to the following equation:
= k ~(t) + kl ~(t-l) ---- + kn ___-- (5) In this case, the time for obtaining values of learned correction coefficient ~L through learned controlling can also be minimized by changing values of the weight coefficients kor kl, ----- kn and consequent-ly optimum control can be performed through learned controlling within a short period of time following the commencement of use by the user.
While in the foregoing embodiment the control speed for learned controlling has been described as being set to a high value before the running distance of the vehicle reaches a predetermined value, the fre-quency of turn-on operations of the ignition switch and start swi.tch may be counted so that when the frequency of the turn-on operations is below a predetermined value, the control speed for learned controlling may be set to a higher value. Through the use of the frequency of the turn-on operations of the ignition switch and start switch in this manner, even when old learned ~2979~i~
1 controlling data are destroyed because of disconnection of the battery effected for repair and inspection, the control speed for learned controlling can readily be set to the higher value before the frequency of the turn-on operations of the ignition switch and start s~itch, starting from the beginning of re-connection of the battery, reaches the predetermined value.
Particularly, automobiles produced in an automobile production factory can be tes-ted in the factory before consignment in a simulation running mode corresponding to a predetermined running mode (Ten mode or LA-~ mode) so as to cause various engine states to occur and accordingly, the engine states can be learned by the automobiles, in advance of consignment thereof, to complete necessary data on the entire area of the RAM.
Although in the foregoing embodiment the learned controlling has been described as applied to fuel injection, the present invention is not limited thereto but may also be applied to, for example, lgni-tion timing control, air/fuel ratio control, idling control and EGR (Exhaust Gas Recycle) control. In the case of ignition timing control, the 2 sensor 5 may be replaced with a sensor 20 Eor detecting the combustion state of the engine such as for example a knocking sensor and a combustion pressure sensor.
As has been described, according to the invention, the engine control apparatus can be provided ~IL2~'79~3 l wherein the control speed for learned controlling is increased under the predetermined condition to permit optimum engine control through learned controlling wi.thin a short period of time following the commencement of use by the user.
This invention relates to an apparatus for controlling an engine such as an internal combustion engine and more particularly to an engine control apparatus having a learned controlling function.
An engine control apparatus having a learned controlling function is disclosed in, for example, JP-A~59-180048. As is clear from the disclosure of the above public literature, in the conventional engine control apparatus having the learned controlling func-tion, irreyularity in characteris-tics of the engine per se and irregularity and secular variation in character-istics of sensors adapted to detect the status of the engine are corrected using the learned controlling function and various controllable quantities such as for example air/fuel ratio and ignition timing can be con-trolled optimumly.
ln the conventional engine control apparatus as exemplified in the a:Eorementioned public literature, however, the control speed Eor learned controlling is unchangeable and it takes a long time to obtain optimum engine control through the learned controlling.
The control speed Eor learned controlling is desired to be high during a predetermined con~ition thereby placing the engine in optimumly controlled .
96~
1 condition through the learned controlling within a short period of time following the commencement of use by the user.
SUMMARY OF THE INVENTION
An object of this invention is to provide an engine control apparatus which can obtain, within a relatively short period of time, correction amounts for correcting irregularity in characteristics of the engine per se and irregularity in characteristics of various sensors so as to control the engine optimumly.
According to the invention, to accomplish theabove object, an engine control apparatus for controlling at least the fuel supply amount representative of the controllable quantities by fetching signals from the sensors adapted to detect the status of the engine comprises learned controlling means ~or controlling the controllable quantity on the basis of the signals from the sensors, and control speed chanyiny means for changing, under a predetermined condition, the control speed for the learned controlliny means to a value which is higher than a reference value.
~z97~ 8 1 In particular, the invention relates to an engine control apparatus comprising: a plurality o~ sensors for detecting selected states of an engine; first calculating means for calculating, on the basis of signals produced .~rom said sensors, a correction amount which corrects a prede-termined controllable quantity; second calculating means for calculating a learning correction amount by averaging values of said correction amount at a predetermined reference occurrence frequency of sampled co.rrection amount values;
means for controlling said second calculating means, in response to detection oE a predetermined condition, by changing the occurrence frequency at which sampled values of the correction amount are averaged to an occurrence frequency which is smaller than said predetermined reference occurrence fre~uency; and means for correcting said control-lable quantity in accordance with said correction amount and said learning correction amount.
With this construction, the control speed changing means sets, under the predetermined condition, the control speed for learned controlling to a higher value than the reEerence value so that the engine can be placed in optimumly controlle~ con~ition throu~h the learned controlling within a short period oE time - 2a -~g7~6~
1 following the commencement of use by the user. At the expiration of a predetermined period of time, the control speed for learned controlling is set to the reference value.
DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic block diagram showing an engine control apparatus according to an embodiment of the invention.
Figure 2 is a time chart showing a correction coefficient changing with the operation of the Fig. 1 apparatus.
Figure 3 is a time chart showing a change in the correction coefficient through learned controlling in the Fig. 1 apparatus.
Figure 4 illustrates a map of learned correc-tion coefficient data in a RAM obtained through learned controlling in the Fig. 1 apparatus.
Figure 5 is a flow chart showing the operation of the Fig. 1 apparatus.
Figure 6 i.s a time chart showing another example of a change in the correction coefEicient throuyh learned controlliny ;n the Fig. 1 apparatus.
DESCRIPTION OF' TEIE PREFERRED EMBODIMENT
An engine control apparatus according to a preferred embodiment of the invention will now be described with reference to Figs. 1 to 6.
s6a 1 Firstly, referring to Fig. 1, an engine 1 has an intake conduit 10 in which an intake air flow rate sensor 2 is disposed having an output terminal connected to a control console 3. Disposed near one end of the intake conduit 10 is an injector 6 for fuel injection to the engine 1, the injector 6 having an input terminal connected to the control console 3.
In an exhaust conduit 11 of the engine 1 is an oxygen (2) sensor 5 having an output terminal connected to the control console 3. In this embodiment, the pulse width for fuel injection to the engine 1 is controlled on the basis of a concentration of oxygen in exhaust gas which is detected by the 2 sensor 5.
A crank angle sensor 4 rotates in synchronism with the rotation of the engine 1 to produce an engine revolution number signal which is applied to the control console 3, and an odometer 7 is connected to the control console 3 to supply thereto a signal indicative of a running distance of a vehicle.
The engine control apparatus constructed as above operates as will be described below.
Where QA is -the intalce air amount which is calculated by the control console 3 on the basis of a flow rate signal measured by the intake air flow rate sensor 2, N is the engine revolution number (per unit time) which is calculated by the control console 3 on the basis of an engine revolution number signal in the form of pulses produced from the crank angle sensor 4 ~2~7~
1 each time the engine rotates a predetermined angle and _ is a constant, the control console 3 calculates the pulse width Tp for fuel injection in accordance with -the following equation:
Tp = k x QA/N _____ (1) The fuel injection amount based on the pulse width Tp for fuel injection as obtained from equation (1) is feedback controlled using a signal produced from the 2 sensor 5. More specifically, where ~ is the feedback correction coefficient and aL is the learned correction coefficient obtained through learned control-ling, the control console 3 comprised of a microcomputer calculates the corrected pulse width Ti for fuel injec-tion in accordance with the following equation:
Ti = Tp x (~ + ~L) ----- (2) The ultimate pulse width for fuel injection to the injector 6 is controlled pursuant to equation (2) The correction coefficient ~ in equ~tion (2) can he obtained through proportional integration control corresponding to the output s1gnal of the 2 sensor 5, as shown in Fig. 2. More particularly, when the air/
fuel ratio changes from "LEAN" to "RICH", for the purpose of rapid controlling, the proportional portion, ~79~S8 1 PR, is subtracted and thereafter the integration portion at the rate of IR is subtracted. Conversely, when the air/fuel ratio changes from "RICH" to "LEAN", for the purpose of rapid controlling, the proportional portion, PL, is added and thereafter the in-tegration portion at the rate of IL is added~
This conventionally available correction based on the correction coefficient ~ alone, however, fails to correct errors in controlling attributable to the difference in individuality of the engines per se of vehicles and manufacture errors (irregularity) or secular variation in the various sensors. ~ccordingly, it has hitherto been also practice to make correction by using the learned correction coefficient ~L obtained through learned controlling. The learned correction coefficient ~L is defined by an average of values of the correction coefficient ~.
Therefore, when the air/fuel ratio changes from fuel "RICH" to fuel "LEAN" or conversely from fuel "LEAN" to fuel "RICH", values of ~ are averaged to determine a value of ~L as shown in Fig. 3. The value f ~L ls -~L in this example. Values of the learned correction coefficient ~L are obtained in relation to various running states and stored in a RAM 3A of the control console 3, as shown in ~ig. 4.
In Fig. 4, data values of the learned correc-tion coef~icient ~L are related to the runnin~ state in which the engine speed becomes higher as the revolution ~7~
1 number N changes to the right on abscissa and the fuel becomes rich, i.e., the load on the engine becomes higher as ~he pulse width Tp for fuel injection changes upwards. Data values ~Ll to ~L24 stored in the RAM 3A
in relation to various operation or running states of the engine are not obtained by uniformly averaging values of ~. Specifically, data values ~L6, L7, ~Llo, 11' ~L14, ~L15, ~L18 and ~L19 on almost the central area in Fig. 4 are related to engine states which occur relatively frequently and can be obtained by averaging many (for example, ten) values of ~. But data values on the peripheral area (for example, ~Ll, ~L4, ~L21 and ~L24) are related to engine states which occur infre-quently and if these data values ~Li are to be deter-mined by the conventlonal method which is designed toaverage, for example, ten values of ~, these data values on the peripheral area will remain undetermined for a long time. When under this condition the engine states which are expected to occur infrequently occur, there results a problem that optimum engine controlling can not be performed by the conventional method.
To solve this problem, the present invention features in that, for example, for a small running distance attributed to a new car, in view of the fact that the new car has poor experience in learning, values of ~ are averaged by a relatively small number (for example, five) to determine data values ~Li, whereby data values ~Li on the entire area of the map of Fig. 4 ~2~6~
1 can be obtained within a relatively short period of time to meet controlling for any englne states. By using the thus obtained a and ~L, the air/fuel ratio can be controlled optimumly pursuant to equation (2).
Referring to Fig. 5, the operational procedure to this end will be described. In step 101, the intake air amount QA is calculated in accordance with a flow rate signal produced from the intake air flow rate sensor 2 and in step 102, the engine revolution number N is calculated in accordance with an engine revolution number signal produced from the crank angle sensor 4.
Subsequently, in s-tep 103, the pulse width Tp for fuel injection is calculated pursuant to equation (1) and in step 104, a signal produced from the 2 sensor 5 is fetched. In step 105, the correction coefficient is calculated on the basis of the signal of the 2 sensor 5 fetched in step 104 through the proportional integration controlling as previously described in connection with Fig. 2, in a manner well known by itself.
The procedure then proceeds to step 106 in which it is decided from a running distance signal produced frorn the odometer 7 whether the running distance of the vehicle is below I Km.
I the running distance of the vehi.cle is decided to be below I Km in step 106, the learned correction coefficient ~L is calculated, in step 108, pursuant to the following equation:
~.2~7g~
~ )/N2 = ~L ~~-~~ (3) 1 If the running distance of the vehicle is decided to exceed I Km in step 106, the learned correction coefficient ~L is calculated, in step 107, pursuant to the following equation:
~ )/Nl = ~L ~~~~~ (4) Since Nl in equation (4) is related to N2 in equation (3) by Nl >>N2, data values of the ].earned correction coefficient ~L can be calculated and deter-mined through learned controlling within a short period of time.
Finally, in step 109, the learned correction coefficient ~L determined pursuant to equation (3) or (4) and the correction coefficient ~ determined in step 105.are used to calculate the pulse width Ti for fuel injection pursuant to equation (2).
As described above, according to this embodi-ment oE the invention, the control speed ~or learned controlling is set to a higher vaJ.ue be~ore the vehicle reaches a predetermined running distance, thereby ensuring that the ai.r/fuel ratio can be controlled optimumly withi.n a short period of time following the commencement of use by the user.
9~;8 1 Fig. 6 shows another way to obtain the learned correction coefficient ~L through learned controlling.
In this example, values of ~ represented by ~(t), ~(t~ (t-n) are multiplied by desired weight coefficients ko~ kl, ----- kn, respectively, to calculate the learned correction coefficient ~L
pursuant to the following equation:
= k ~(t) + kl ~(t-l) ---- + kn ___-- (5) In this case, the time for obtaining values of learned correction coefficient ~L through learned controlling can also be minimized by changing values of the weight coefficients kor kl, ----- kn and consequent-ly optimum control can be performed through learned controlling within a short period of time following the commencement of use by the user.
While in the foregoing embodiment the control speed for learned controlling has been described as being set to a high value before the running distance of the vehicle reaches a predetermined value, the fre-quency of turn-on operations of the ignition switch and start swi.tch may be counted so that when the frequency of the turn-on operations is below a predetermined value, the control speed for learned controlling may be set to a higher value. Through the use of the frequency of the turn-on operations of the ignition switch and start switch in this manner, even when old learned ~2979~i~
1 controlling data are destroyed because of disconnection of the battery effected for repair and inspection, the control speed for learned controlling can readily be set to the higher value before the frequency of the turn-on operations of the ignition switch and start s~itch, starting from the beginning of re-connection of the battery, reaches the predetermined value.
Particularly, automobiles produced in an automobile production factory can be tes-ted in the factory before consignment in a simulation running mode corresponding to a predetermined running mode (Ten mode or LA-~ mode) so as to cause various engine states to occur and accordingly, the engine states can be learned by the automobiles, in advance of consignment thereof, to complete necessary data on the entire area of the RAM.
Although in the foregoing embodiment the learned controlling has been described as applied to fuel injection, the present invention is not limited thereto but may also be applied to, for example, lgni-tion timing control, air/fuel ratio control, idling control and EGR (Exhaust Gas Recycle) control. In the case of ignition timing control, the 2 sensor 5 may be replaced with a sensor 20 Eor detecting the combustion state of the engine such as for example a knocking sensor and a combustion pressure sensor.
As has been described, according to the invention, the engine control apparatus can be provided ~IL2~'79~3 l wherein the control speed for learned controlling is increased under the predetermined condition to permit optimum engine control through learned controlling wi.thin a short period of time following the commencement of use by the user.
Claims (4)
1. An engine control apparatus comprising:
a plurality of sensors for detecting selected states of an engine;
first calculating means for calculating, on the basis of signals produced from said sensors, a correction amount which corrects a predetermined controllable quantity;
second calculating means for calculating a learning correction amount by averaging values of said correction amount at a predetermined reference occurrence frequency of sampled correction amount values;
means for controlling said second calculating means, in response to detection of a predetermined condition, by changing the occurrence frequency at which sampled values of the correction amount are averaged to an occurrence frequency which is smaller than said predetermined reference occurrence frequency; and means for correcting said controllable quantity in accordance with said correction amount and said learning correction amount.
a plurality of sensors for detecting selected states of an engine;
first calculating means for calculating, on the basis of signals produced from said sensors, a correction amount which corrects a predetermined controllable quantity;
second calculating means for calculating a learning correction amount by averaging values of said correction amount at a predetermined reference occurrence frequency of sampled correction amount values;
means for controlling said second calculating means, in response to detection of a predetermined condition, by changing the occurrence frequency at which sampled values of the correction amount are averaged to an occurrence frequency which is smaller than said predetermined reference occurrence frequency; and means for correcting said controllable quantity in accordance with said correction amount and said learning correction amount.
2. An engine control apparatus according to claim 1 wherein said plurality of sensors include a vehicle running distance sensor, an intake air flow rate sensor, an engine revolution number sensor and an oxygen sensor, said controllable quantity is a fuel supply amount, and said predetermined condition is determined on the basis of an output signal produced from said vehicle running distance sensor .
3. An engine control apparatus according to claim 1 wherein said plurality of sensors include a vehicle running distance sensor, an intake air flow rate sensor, an engine revolution number sensor and an engine state sensor, said controllable quantity is the ignition timing, and said predetermined condition is determined on the basis of an output signal produced from said vehicle running distance sensor.
4. An engine control apparatus according to claim 1 wherein said plurality of sensors include an intake air flow rate sensor, an engine revolution number sensor and an oxygen sensor, said controllable quantity is the fuel supply amount, and said predetermined condition is determined on the basis of a frequency of turn-on operations of an engine start switch.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62056614A JP2555055B2 (en) | 1987-03-13 | 1987-03-13 | Engine controller |
| JP62-56614 | 1987-03-13 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1297968C true CA1297968C (en) | 1992-03-24 |
Family
ID=13032136
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000561069A Expired - Lifetime CA1297968C (en) | 1987-03-13 | 1988-03-10 | Engine control apparatus |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US4836169A (en) |
| EP (1) | EP0282055B1 (en) |
| JP (1) | JP2555055B2 (en) |
| KR (1) | KR880011448A (en) |
| CA (1) | CA1297968C (en) |
| DE (1) | DE3871408D1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01216054A (en) * | 1988-02-24 | 1989-08-30 | Fuji Heavy Ind Ltd | Controller for fuel injection of engine |
| US5054451A (en) * | 1988-03-25 | 1991-10-08 | Toyota Jidosha Kabushiki Kaisha | Control apparatus for internal combustion |
| US4922877A (en) * | 1988-06-03 | 1990-05-08 | Nissan Motor Company, Limited | System and method for controlling fuel injection quantity for internal combustion engine |
| FR2772079B1 (en) * | 1997-12-08 | 2000-02-18 | Renault | METHOD AND DEVICE FOR CONTROLLING THE INJECTION OF AN INTERNAL COMBUSTION ENGINE |
| DE19807215C2 (en) * | 1998-02-20 | 2000-06-08 | Siemens Ag | Control system for an internal combustion engine |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5420203A (en) * | 1977-07-15 | 1979-02-15 | Hitachi Ltd | Combustion control equipment of engine |
| JPS5578168A (en) * | 1978-12-07 | 1980-06-12 | Nippon Soken Inc | Feedback type ignition time control device for internal combustion engine |
| US4309971A (en) * | 1980-04-21 | 1982-01-12 | General Motors Corporation | Adaptive air/fuel ratio controller for internal combustion engine |
| JPS6088813A (en) * | 1983-10-20 | 1985-05-18 | Mazda Motor Corp | Exhaust purifying device for engine |
| KR890000497B1 (en) * | 1983-11-21 | 1989-03-20 | 가부시기가이샤 히다찌세이사꾸쇼 | Method of controlling air fuel ratio |
| JPS6125949A (en) * | 1984-07-13 | 1986-02-05 | Fuji Heavy Ind Ltd | Electronic control for car engine |
| JPS6128739A (en) * | 1984-07-20 | 1986-02-08 | Toyota Motor Corp | Method of controlling learning value for internal-combustion engine |
| JPS61149536A (en) * | 1984-12-25 | 1986-07-08 | Honda Motor Co Ltd | Method of controlling motion control amount of internal-combustion engine with supercharger |
| JPS61152935A (en) * | 1984-12-26 | 1986-07-11 | Fuji Heavy Ind Ltd | Air-fuel ratio controlling device |
| JPS61157766A (en) * | 1984-12-28 | 1986-07-17 | Fuji Heavy Ind Ltd | Ignition timing control system for internal-combustion engine |
| US4597368A (en) * | 1985-02-25 | 1986-07-01 | General Motors Corporation | Engine idle speed control system |
| JPS6397843A (en) * | 1986-10-13 | 1988-04-28 | Nippon Denso Co Ltd | Fuel injection control device for internal combustion engine |
-
1987
- 1987-03-13 JP JP62056614A patent/JP2555055B2/en not_active Expired - Lifetime
-
1988
- 1988-02-24 US US07/159,904 patent/US4836169A/en not_active Expired - Lifetime
- 1988-03-02 KR KR1019880002147A patent/KR880011448A/en not_active Application Discontinuation
- 1988-03-10 DE DE8888103798T patent/DE3871408D1/en not_active Expired - Lifetime
- 1988-03-10 CA CA000561069A patent/CA1297968C/en not_active Expired - Lifetime
- 1988-03-10 EP EP88103798A patent/EP0282055B1/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| EP0282055B1 (en) | 1992-05-27 |
| DE3871408D1 (en) | 1992-07-02 |
| EP0282055A2 (en) | 1988-09-14 |
| JPS63223354A (en) | 1988-09-16 |
| KR880011448A (en) | 1988-10-28 |
| US4836169A (en) | 1989-06-06 |
| EP0282055A3 (en) | 1989-10-04 |
| JP2555055B2 (en) | 1996-11-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4321903A (en) | Method of feedback controlling air-fuel ratio | |
| US5182907A (en) | System for monitoring performance of HC sensors for internal combustion engines | |
| US5777204A (en) | Air-fuel ratio detecting device and method therefor | |
| US5216882A (en) | System for detecting deterioration of HC sensors for internal combustion engines | |
| CA1297968C (en) | Engine control apparatus | |
| US4966111A (en) | Fuel supply control system for internal combustion engines | |
| US4698765A (en) | Ignition timing control system for an automotive engine | |
| EP0281962A2 (en) | Control apparatus for internal combustion engine | |
| US5113347A (en) | Internal combustion engine speed controller for controlling a throttle valve bypass with respect to the atmospheric pressure | |
| US4522180A (en) | Air-fuel ratio control apparatus | |
| US4913120A (en) | Air-fuel ratio feedback control method for internal combustion engines | |
| EP0230318B1 (en) | Fuel injection control system for internal combustion engine | |
| US4864999A (en) | Fuel control apparatus for engine | |
| US4712522A (en) | Method and apparatus for controlling air-fuel ratio in internal combustion engine | |
| US5992389A (en) | Apparatus and method for controlling fuel injection of an internal combustion engine | |
| JPH0529775B2 (en) | ||
| KR100337501B1 (en) | Method for controlling amount of fuel to be injected during acceleration/deceleration in a motor vehicle having electronic fuel injection system | |
| JPH1193736A (en) | Idling rotation learning control device for electronically controlled throttle valve type internal combustion engine | |
| RU2170359C2 (en) | Internal combustion engine control method | |
| EP0964144B1 (en) | Fuel injection control apparatus of multicylinder internal combustion engine | |
| JPH05149187A (en) | Atmospheric pressure correction method for engine | |
| KR100195475B1 (en) | Fuel control system according to the running mode | |
| JP3478713B2 (en) | Air-fuel ratio control device for internal combustion engine | |
| KR100405720B1 (en) | Fuel injection control method for engine | |
| JPH09189252A (en) | Idle speed learning controller for engine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |