JP4158932B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine mounted on a vehicle, for example, and particularly to a technique for controlling an intake air amount to the internal combustion engine.

  A conventional control device for an internal combustion engine is provided in an intake air amount control module (throttle valve device) for controlling the intake air amount (air flow rate passing through the intake system) to the internal combustion engine, and the intake air amount control module. Non-volatile storage element for storing information for amount control, intake amount control mechanism (throttle valve) provided in the throttle body of the intake amount control module, and position detection device (throttle opening degree) of the intake amount control mechanism Sensor), and is configured to store the maximum value of the throttle opening detected by the position detection device in a nonvolatile memory element (see, for example, Patent Document 1).

  Further, the intake air amount control module of the conventional device has a communication terminal for communicating with an external device, and when the maximum value of the throttle opening is stored in a nonvolatile element, the maximum value from the communication terminal. When the storage command is received, the maximum value is stored in the non-volatile memory element, and the throttle opening degree is set to the fully open value based on the maximum value, thereby suppressing variations in the control amount related to the intake air amount. Yes.

In many conventional apparatuses, the fully closed position of the throttle valve is learned each time the ignition key is turned ON / OFF, and the learned fully closed position is used as a reference for throttle control.
Therefore, the opening degree of the throttle valve is represented by a relative position based on the output value (detection opening degree) of the throttle opening degree sensor at the fully closed position.

In this case, a detection error caused by an attachment error of the intake air amount control module to the internal combustion engine, that is, a correlation error generated between the actual throttle opening and the detected opening (TPS output) of the throttle opening sensor. Can learn.
However, it is not possible to learn a detection error caused by processing variations of the internal combustion engine and the intake air amount control module, that is, a correlation variation generated between the throttle opening and the actual intake air amount.

  The variation between the actual throttle valve opening and the intake air amount is caused by, for example, the processing variation of the valve diameter of the throttle valve or the processing variation of the inner diameter of the flow path. This is because the opening area is different even at the same throttle opening. Such variations due to machining errors have a great influence especially at low opening.

Thus, in the conventional device, control based on the relative position from the detected opening of the throttle opening sensor in the fully closed position (hereinafter referred to as “throttle relative opening based control”) is performed. The engine is controlled in a state where the relationship between the throttle opening and the actual intake air amount is unclear.
In this case, even if the required target intake air amount is instructed to the intake air amount control module, the control is executed at the relative position of the throttle opening, so that the intake air amount is controlled to be different from the target flow rate.
This is because, due to individual variations in the intake air amount control module and the like, even if the detected opening shows the same throttle opening, a different intake amount is actually obtained.

In particular, when the intake air amount control module is disposed in the intake air collecting portion of the internal combustion engine, the intake air amount varies from vehicle to vehicle, which may lead to a sense of incongruity during vehicle driving and deterioration of drivability. There is.
Further, in a multi-cylinder (for example, four cylinder) internal combustion engine, when a plurality of intake air amount control modules are provided corresponding to each cylinder, the intake air amount flowing into each cylinder is different. In addition to problems (such as a sense of incongruity during driving and deterioration of drivability), problems such as rotational fluctuations of the internal combustion engine and unstable combustion may occur.

  FIG. 30 and FIG. 31 are explanatory diagrams showing the opening-flow rate (intake amount) characteristics for explaining the above-described problem. The reference throttle opening position characteristics (hereinafter referred to as “designated targets” for the intake amount control module). (Refer to a solid line) and a position characteristic of an actual throttle opening including variation (hereinafter referred to as an “actual TPS characteristic”) (refer to a broken line). FIG. 31 shows only the low flow rate region in FIG. 30 in an enlarged manner.

30 and 31, the vertical axis represents the intake air amount (flow rate) [g / sec], the horizontal axis represents the throttle opening [%], and the “black square mark” corresponding to the dashed curve represents the plot value of the actual TPS, The “black rhombus mark” corresponding to the solid curve is a plot value of the reference TPS.
In FIG. 31, for example, when a throttle opening degree of 10 [%] is instructed, the flow rate at the actual TPS characteristic (dashed line) with respect to the flow rate at the reference characteristic (solid line) (approximately 13 [g / sec]) is It is reduced to 11.2 [g / sec] due to individual variation factors.

Therefore, in actuality, the intake air amount is about 14% less than the requested target flow rate. As described above, when the intake air amount control module is disposed in the intake air collecting portion of the internal combustion engine, Therefore, the intake air amount varies, and there is a concern about the difference in running feeling and the deterioration of drivability.
In particular, when an intake air amount control module is provided in each cylinder of a multi-cylinder (for example, 4 cylinders) internal combustion engine, a difference occurs in the intake air amount to each cylinder. It may cause fluctuation and combustion instability.

JP 2004-52676 A

  In a conventional control device for an internal combustion engine, the fully closed position and the fully open position of the throttle valve are learned. Although the variation with respect to the throttle valve opening can be suppressed, the actual throttle valve opening and intake air amount can be suppressed. Since there is a variation in the relationship (actual TPS characteristics) with the above, there is a problem that a large control error occurs particularly at a low opening.

  The present invention solves the above-described problem, and attaches an intake air amount control module including a throttle opening sensor by correcting and measuring (learning) the relationship between the throttle opening and the actual intake air in advance. After suppressing the effects of errors and processing variations, control based on the characteristic relationship between the throttle opening and the actual intake air amount (hereinafter referred to as “opening-intake air amount-based control”) is executed. An object of the present invention is to obtain a control device for an internal combustion engine that enables accurate control of the intake air amount.

The present invention for an internal combustion engine control apparatus according to the comprises an ECU for controlling an internal combustion engine, an intake amount control module for controlling the amount of intake air to the internal combustion engine, the intake air amount control module, the intake air amount for adjusting the intake air amount The controller includes an adjusting means, an opening detecting means for detecting the opening of the intake air amount adjusting means, a driving means for driving the intake air amount adjusting means, and a controller for controlling the driving means. The controller detects the opening detecting means. A control device for an internal combustion engine that controls the opening degree of the intake air amount adjusting means by controlling the driving means based on the opening degree, wherein the controller includes a storage element that stores control information for the driving means, and an intake air amount control In order to measure the intake air amount passing through the intake air amount control module when learning the relationship between the opening degree of the intake air amount adjusting means in the module and the intake air amount to the internal combustion engine, An opening degree storage means for storing the detected opening degree of the opening degree detecting means when the measured value of the intake air amount by an external device connected to the battery indicates a predetermined value, and an intake air amount adjusting means obtained from a predetermined reference characteristic The reference value of the opening is stored in the storage element, the opening comparison means for comparing the detected opening and the reference value stored in the storage element, and the comparison result by the opening comparison means Based on the opening degree correcting means for correcting the target opening degree of the intake air amount adjusting means, and controlling the driving means so that the target opening degree corrected by the opening degree correcting means matches the opening degree of the intake air amount adjusting means. An opening correction means for ECU input for correcting the opening of the intake air amount adjusting means based on the comparison result by the opening comparison means, and the opening degree storage means and the opening reference value storage means are an intake air amount control module. In contrast, an external device is installed instead of the internal combustion engine. When the internal combustion engine is installed in place of the external device, the intake air amount control module performs the storage processing and the target opening degree corrected by the opening degree correcting means and the opening degree of the intake air amount adjusting means. Are controlled so as to coincide with each other, and the opening corrected by the opening correction means for ECU input is input to the ECU .

  According to the present invention, an internal combustion engine is provided with an intake air amount control module in which the relationship between the throttle opening and the actual intake air amount is clarified in advance based on the detected opening of the throttle valve (TPS output) and the actual intake air amount. By incorporating and using, not only the relative error between the throttle opening caused by the installation error of the intake air control module and the detected opening of the throttle opening sensor, but also the throttle opening due to processing variations of the intake air control module, etc. Variations among individual intake air amount control modules, including variations in the relationship with intake air amount, are suppressed, so there is no influence of mounting errors or processing variations, and the throttle opening and actual intake air amount are not affected. Accurate intake air amount control based on the relationship can be realized.

Embodiment 1 FIG.
Hereinafter, the first embodiment of the present invention will be described in detail with reference to the drawings.
1 is a block diagram schematically showing an intake air amount control module of an internal combustion engine control apparatus according to Embodiment 1 of the present invention.

  In FIG. 1, an intake air amount control module (hereinafter referred to as “ETV module”) 1 for controlling the intake air amount to an engine (internal combustion engine) 10 adjusts the intake air amount of air (see arrows) flowing through the intake pipe 11. A throttle valve (intake air amount adjusting means) 2 for opening, a throttle actuator (driving means) 3 for driving the throttle valve 2 to open and close, and a throttle opening degree sensor (hereinafter referred to as “TPS”) for detecting the throttle opening degree D of the throttle valve 2 ) 4 and a module controller unit (hereinafter referred to as “MCU”) 5 for controlling the throttle actuator 3.

  The MCU 5 includes a CPU and a nonvolatile memory element (hereinafter referred to as “EEPROM”) (both not shown), receives the throttle opening D detected from the TPS 4, and controls the throttle actuator 3.

After being assembled as an integral ETV module 1 together with the throttle valve 2, the throttle actuator 3 and the TPS 4, the MCU 5 learns the relationship between the actual intake air amount passing through the ETV module 1 and the throttle opening, as will be described later. The relationship between the intake air amount and the throttle opening is stored in advance in the EEPROM as a table.
Thereby, the inter-individual variation of the ETV module 1 is compensated and reduced.

Further, the MCU 5 is connected to an engine control unit (hereinafter referred to as “ECU”) 6 and is communicable with the ECU 6 during normal operation of the engine 10 as shown in FIG.
During normal operation, the ECU 6 controls the ETV module 1 and the engine 10 in cooperation with the MCU 5.
For example, the MCU 5 receives the required target throttle opening degree Do from the ECU 6 and controls the throttle actuator 3 so that the throttle opening degree D coincides with the target throttle opening degree Do (target intake air amount).

Note that the ECU 6 passes not only the throttle opening D from the TPS 4 but also detection signals (accelerator opening α, ETV module 1) from various not-shown sensors (accelerator position sensor, intake air amount sensor, water temperature sensor, etc.). The target throttle opening degree Do is calculated on the basis of the air flow rate, that is, the intake air amount A, the coolant temperature Tw of the engine 10, and the like.
The ECU 6 controls the MCU 5 based on the throttle opening D and various sensor signals (α, A, Tw) input via the MCU 5, and controls the opening of the throttle valve 2 via the throttle actuator 3. .

FIG. 2 is a block diagram showing the state of the ETV module 1 when measuring the intake air amount. Components similar to those described above (see FIG. 1) are denoted by the same reference numerals as those described above, and detailed description thereof is omitted.
In FIG. 2, a vacuum pump 42 is installed in the intake pipe 11 having the ETV module 1 as an external device instead of the engine 10.

An intake air amount measuring device 43 for measuring the intake air amount passing through the ETV module 1 is installed on the upstream side of the intake pipe 11 as an external device.
Further, a module control panel 44 is connected to the MCU 5 of the ETV module 1 instead of the ECU 6.

The vacuum pump 42 has a meter 42a for displaying the negative pressure value in the intake pipe 11, and the intake air amount measuring device 43 has a display device 43a for displaying the intake air amount measured value.
Similarly, the module control panel 44 has a display 44a for displaying the detected opening of the TPS 4 and displays 44b and 44c for displaying other sensor information and tables (described later).

Further, the module control board 44 sends out an instruction for storing the detected opening of the TPS 4 under each condition, that is, an instruction for sequentially storing the detected opening in the EEPROM in the MCU 5.
As shown in FIG. 2, the MCU 5 of the ETV module 1 is connected to the module control panel 44 and stores various measurement information when measuring the intake air amount.
Further, the MCU 5 is connected to the ECU 6 at a normal time after measuring the intake air amount, and transfers necessary information to the ECU 6 as control information of the ETV module 1 as shown in FIG.

FIG. 3 is a block diagram showing a functional configuration of the MCU 5 according to the first embodiment of the present invention. A broken arrow indicates a signal flow during measurement learning by the apparatus configuration of FIG. 2, and a solid arrow indicates the apparatus of FIG. The flow of the signal at the time of the normal driving | operation by the structure is shown.
In FIG. 3, the MCU 5 detects the TPS 4 when the measured value of intake air by the intake air measuring device 43 (external device) shows a predetermined value, and an EEPROM (storage element) 50 that stores learning information, control information, and the like as a table. An opening degree storage means 51 for storing the opening degree in the storage element, an opening degree reference value storage means 52 for storing the opening degree reference value of the throttle valve 2 obtained from predetermined reference characteristics (described later) in the storage element, and the throttle And a control unit 53 that operates the actuator 3.

The control unit 53 includes functions of an opening degree comparison unit and an opening degree correction unit during measurement learning.
The opening degree comparison means in the control unit 53 compares the detected opening degree stored in the EEPROM 50 with the opening reference value at the time of measurement learning.
Further, the opening degree correction means in the control unit 53 creates a table for correcting the target opening degree Do of the throttle valve 2 based on the comparison result by the opening degree comparison means at the time of measurement learning, and compensates for variations. The table is stored in the EEPROM 50.

  Further, the control unit 53 operates the throttle actuator 3 in response to an opening amount instruction from the module control panel 44 during measurement learning, and from the target opening Do and the EEPROM 50 from the ECU 6 during normal operation. Based on the read table, the throttle actuator 3 is controlled so that the detected opening D of the throttle valve 2 matches the corrected target opening corrected by the opening correction means.

Next, the throttle opening learning processing operation according to the first embodiment of the present invention will be described with reference to the flowchart of FIG. 4 and the explanatory views of FIGS. 5 and 6 together with FIGS.
The processing procedure in FIG. 4 is executed by an operator's operation in the configuration for measuring the intake air amount shown in FIG.

FIG. 5 is a table before the execution of the learning process (FIG. 4), and shows a known reference TPS value (1.7 [%]) at the minimum flow rate (5.00 [g / sec]).
FIG. 6 is a table after the execution of the learning process (FIG. 4). The reference TPS value (1.7 [%]) at the minimum flow rate (5.00 [g / sec]) and the actual TPS after learning. The value (3.1 [%]) is shown.

  4 to 6, the TPS value in the reference characteristic (solid curve) in FIG. 30 and FIG. 31 described above is a known reference TPS value before learning, and the actual TPS in FIG. 30 and FIG. The TPS value in the characteristic (see the broken line) is the actual TPS value after learning.

  4, first, as shown in FIG. 2, a vacuum pump 42, an intake air amount measuring device 43 and a module control panel 44 (see FIG. 2) are connected to the ETV module 1 which has been assembled, and the ETV module 1 is connected to the ETV module 1 from the module control panel 44. An instruction from the throttle actuator 3 is sent to the MCU 5 of the module 1 to operate the throttle valve 2 (step S101).

Subsequently, the vacuum pump 42 is operated to generate a negative pressure in the intake pipe 11 (step S102).
At this time, the vacuum pump 42 is driven at a negative pressure so that the negative pressure in the intake pipe 11 is, for example, a differential pressure from the atmospheric pressure is about 66.7 [kPa].

  Next, the operator operates the module control panel 44 while referring to a known table (FIG. 5) displayed on the display 44c, for example, so that the opening degree of the throttle valve 2 is the minimum flow rate (5.00 [g / sec. ] Is sent from the module control panel 44 to the ETV module 1 to operate the throttle actuator 3 (step S103).

Next, the minimum flow rate (5.00 [g / sec]) is compared with the current measured intake air amount measured by the intake air measuring device 43 (at the minimum air flow) to determine the magnitude relationship between the two. (Step S104).
If the result of determination in step S104 indicates that the measured intake air amount is greater than the minimum flow rate, the process proceeds to step S105. If the measured intake air amount is less than the minimum flow rate, the process proceeds to step S106. move on.

  In step S105, the operator operates the module control panel 44 so that the measured intake air amount matches the minimum flow rate in the table (FIG. 5), and instructs the opening amount so that the throttle valve 2 is controlled to the closed side. Then, the throttle actuator 3 is operated, and the process returns to the determination step S104.

  In step S106, the operator operates the module control panel 44 so that the measured intake air amount coincides with the minimum flow rate, generates an opening amount instruction so that the throttle valve 2 is controlled to open, and the throttle actuator 3 is operated, and the process returns to the determination step S104.

Finally, when the measured intake air amount value = the minimum flow rate, the operator operates the module control panel 44 to send a storage instruction signal to the minimum flow rate storage area from the module control panel 44 to the MCU 5, The detected opening (for example, 3.1 [%]) of the TPS4 when it coincides with the minimum flow rate is stored as an actual TPS value in the minimum flow rate storage area of the EEPROM in the MCU 5 (step S107), and is shown in FIG. The learning process of the TPS detection opening is ended.
As a result of the above processing, as shown in FIG. 6, a correspondence table of the flow rate [g / sec], the reference TPS value [%], and the actual TPS value [%] is obtained.

By executing the learning process, information indicating the relationship between the throttle opening degree D and the intake air amount is stored in the MCU 5 in the intake air amount control module 1 with a relatively small processing procedure.
Accordingly, during normal operation, the MCU 5 corrects the control command (target throttle opening degree Do) from the ECU 6 based on the variation compensation table information stored in the EEPROM, and sets the corrected target opening degree and The throttle valve 2 is driven so as to match.
Further, after completing the drive control of the throttle valve 2, the MCU 5 transfers a signal indicating that the corrected target opening is the target throttle opening Do to the ECU 6.

In this way, by using the control information corrected in the MCU 5 as the control information of the ECU 6, characteristic variations among the individual intake air amount control modules 1 are absorbed, and the controllability can be improved.
In particular, when a plurality of intake air amount control modules 1 are used simultaneously, it becomes easy to align the intake air amount of each individual.

Next, the intake air amount control operation of the engine 10 at the normal time according to the first embodiment of the present invention will be described with reference to the flowcharts of FIGS. 1 and 7.
FIG. 7 shows a processing procedure of the MCU 5 and the ECU 6 at the time of opening degree control of the ETV module 1, and the ETV module 1 storing the table of FIG. 6 (relationship between intake air amount, reference TPS value and actual TPS value) is used. In this case, the intake air amount of the engine 10 is controlled.

  In FIG. 7, first, the ECU 6 determines the target throttle opening D1 (for example, for example, based on the accelerator opening α from the accelerator position sensor, the cooling water temperature Tw from the water temperature sensor, and the intake air amount A from the intake air sensor. 8 [%]) is calculated, and a drive request for the target throttle opening D1 is sent to the MCU 5 of the intake air amount control module 1 (step S201).

Subsequently, in response to the drive request from the ECU 6, the MCU 5 refers to the learned table (FIG. 6) and obtains an actual TPS value E1 for the target throttle opening D1 (8 [%]) (step S202). .
At this time, the actual TPS value E1 is obtained by adding the offset value obtained from the reference TPS value at the minimum flow rate stored in the MCU 5 and the actual TPS value (FIG. 6) in the learning process (FIG. 4).

  For example, when the target throttle opening D1 is 8 [%], the offset amount is calculated from the reference TPS value (1.7 [%]) and the actual TPS value (3.1 [%]) at the minimum flow rate in FIG. Is 1.4 [%] (= 3.1 [%]-1.7 [%]), so the actual TPS value E1 corresponding to the target throttle opening D1 (8 [%]) is 9. 4 [%] (= 8 [%] + 1.4 [%]).

Next, the MCU 5 drives the throttle actuator 3 so that the detected opening actually measured by the TPS 4 coincides with the actual TPS value E1 (= 9.4 [%]) (step S203).
At this time, the corrected actual TPS value E1 set based on the variation compensation table (FIG. 6) ensures that the intake air amount required by the ECU 6 is reliably supplied to the engine 10.

Finally, the MCU 5 sets the detected opening (= E1) of the TPS4 when the detected opening of the TPS4 coincides with the actual TPS value E1 (9.4 [%]) after the driving of the throttle valve 2 is completed. The throttle opening corresponding to the throttle opening D1 (= 8 [%]) is input to the ECU 6 (step S204), and the process of FIG. 7 is terminated.
As a result, the ECU 6 can supply the required intake air amount to the engine 10 only by commanding the target throttle opening degree Do without taking into account individual variation factors of the ETV module 1 or the like.

  In the above process, the TPS value is processed using the offset value from the reference TPS value and the actual TPS value (FIG. 6) at the minimum flow rate, and the actual TPS value (corrected target opening) corresponding to the target throttle opening Do. However, the reference characteristic (solid line) and the actual TPS characteristic (broken line) in FIG. 30 may be calculated assuming that the flow rate (intake amount) when the throttle is fully open (100 [%]) is the same. Good.

Specifically, as shown in FIG. 8, for each of the known minimum flow rate (minimum intake air amount) A1, the unknown flow rate (intake air amount) A2, and the known fully open flow rate (full open intake air amount) A3, the reference TPS Values B1 to B3 and actual TPS values C1 to C3 can be obtained.
In FIG. 8, the reference TPS values B1 and B3 respectively corresponding to the known minimum flow rate A1 and the fully open flow rate A3 are known. Further, the actual TPS value C3 corresponding to the known fully opened flow rate A3 is known.

On the other hand, the actual TPS value C1 for the known minimum flow rate A1 is obtained by measurement.
Here, when the actual TPS value C3 with respect to the known full opening flow rate A3 is set to 100%, when the unknown actual TPS value C2 with respect to the indicated opening B2 is obtained by interpolation, the actual TPS value C2 is expressed by the following equation (1 ).

  C2 = (C3-C1) × (B2-B1) / (B3-B1) + C1 (1)

  As described above, the relationship between the intake air amount, the reference TPS value, and the actual TPS value (table of FIG. 6) is stored in the MCU 5 of the ETV module 1, and the processing based on the relationship of FIG. Compared to the conventional control based on the opening, the variation among the throttles due to the variation in the relationship between the throttle opening and the intake air due to the processing variation is suppressed, and the reliability of the engine 10 based on the opening-intake air is highly reliable. Sex control can be easily realized.

According to the first embodiment of the present invention, an ECU 6 that controls the engine 10, a throttle valve 2 (intake amount adjusting means), a throttle actuator 3 (driving means), a TPS4 (opening degree detecting means), and a throttle actuator 3, an ETV module 1 including an MCU 5 (controller) including an EEPROM (storage element) for controlling 3, and an intake air measuring device 43 (external device) for measuring the intake air amount passing through the ETV module 1 (in the ETV module 1 MCU 5 is connected to the ETV module 1 when learning the relationship between the opening degree of the throttle valve 2 and the intake air amount to the engine 10), and the MCU 5 detects the opening degree when the measured intake air amount shows a predetermined value. Is stored in the EEPROM, and an opening reference value (a preset value) obtained from a predetermined reference characteristic is stored in the EEPROM. An opening reference value storage means stored in the EPROM, an opening comparison means for comparing the stored detected opening and the opening reference value, and a target opening of the throttle valve 2 is corrected based on the opening comparison result. The driving means is controlled so that the opening degree correction means (step S202) and the target opening degree corrected by the opening degree correction means coincide with the opening degree of the intake air amount adjustment means. And an opening degree correction means for ECU input (step S204) for correcting the opening degree of the intake air amount adjusting means based on the opening degree storage means and the opening degree reference value storage means in place of the engine 10 with respect to the ETV module 1. When the intake air amount measuring device 43 is installed, the storage process is executed. When the engine 10 is installed instead of the intake air amount measuring device 43, the ETV module 1 corrects the target opening corrected by the opening degree correcting means. Degree and intake With the opening of the adjusting means controls the driving means so as to coincide, the opening which has been corrected by the ECU input opening correction means is input to the ECU 6, matching the degree of opening of the throttle valve 2 is the corrected target opening Since the throttle actuator 3 is controlled to do so, the detected opening of the TPS 4 can be substantially corrected to the variation canceling side.

  In this way, by using the ETV module 1 in which the relationship between the throttle opening and the actual intake air amount is clarified, the throttle opening due to the installation error of the ETV module 1 and the output of the TPS 4 (detected opening) ) As well as variations in the relationship between the throttle opening and the intake air amount due to processing variations, etc., are suppressed, and are affected by mounting errors and processing variations. Therefore, control based on the relationship between the throttle opening and the actual intake air amount can be performed, and accurate intake air amount control can be realized.

In particular, since the minimum flow rate that can be adjusted by the throttle valve 2 is used as the predetermined value of the measured intake air amount, the correction can be effectively performed in a low flow rate region where the variation in the opening degree-intake air amount characteristic is large. it can.
Moreover, although the operator performed the learning process of FIG. 4, it may be configured to be automatically executed by the MCU 5.

Embodiment 2. FIG.
In the first embodiment, the relationship between the intake air amount, the reference TPS value, and the actual TPS value (see FIG. 6) is stored in the ETV module 1 only at the minimum flow rate, and the throttle opening is controlled. The relationship between the amount, the reference TPS value, and the actual TPS value may be stored as a table including the minimum flow rate and used for controlling the throttle opening.

Hereinafter, an internal combustion engine control apparatus according to Embodiment 2 of the present invention using a table including a minimum flow rate will be described with reference to FIGS. 9 to 18 together with FIGS.
In this case, the device configuration and the functional configuration of the MCU 5 during normal operation and when measuring the intake air amount of the ETV module 1 are the same as those described above (see FIGS. 1 to 3).

FIG. 9 is a flowchart showing a processing procedure when measuring the intake air amount (during throttle opening learning) of the ETV module 1 according to Embodiment 2 of the present invention.
The processing routine of FIG. 9 is executed in the apparatus configuration shown in FIG.
In FIG. 9, steps S301 and S302 are the same processes as steps S101 to S102 described above (see FIG. 4), and steps S304 to S308 are processes corresponding to steps S103 to S107 described above (see FIG. 4). is there.

FIGS. 10 and 11 are explanatory diagrams showing tables corresponding to FIGS. 5 and 6, and FIG. 10 is a table of known reference TPS values before the learning process (FIG. 9) is executed. FIG. 11 is a table of actual TPS values after executing the learning process (FIG. 9).
10 and 11, each TPS value is the reference point No. of the lowest flow rate. 1 to reference point No. for maximum flow rate. It is assumed that the flow rate is set to 16 division points up to 16 [g / sec]. No. in FIG. Each TPS value corresponding to 1 is the same as the table values in FIGS. 5 and 6 described above.

First, a learning process according to the second embodiment of the present invention will be described with reference to FIG. 2 and FIGS.
In this case, the MCU 5 in the ETV module 1 has a counter N for setting reference points (Nos. 1 to 16) of each table (FIGS. 10 and 11).
Therefore, the learning operation of the intake air amount measurement value using the intake air amount measuring device 43 (see FIG. 2) is repeatedly executed for every intake air amount obtained by dividing the entire flow rate region from the minimum flow rate to the maximum flow rate into 16 parts.

In FIG. 9, first, similarly to the above (see FIG. 4), the operator connects the vacuum pump 42, the intake air amount measuring device 43 and the module control panel 44 to the ETV module 1 (step S301), and the vacuum pump 42 is turned off. Pressure driving is performed (step S302).
Subsequently, after initially setting the value of the counter N to “N = 1” (step S303), referring to a known table (FIG. 10), the detected opening of the TPS4 becomes the Nth reference TPS value. Then, the module control panel 44 is operated to drive the throttle valve 2 via the throttle actuator 3 (step S304).

Next, the Nth flow rate (intake amount) in the table of FIG. 10 is compared with the measured intake amount (current intake amount) actually measured by the intake amount measuring device 43, and the magnitude relationship between the two is compared. Is determined (step S305).
If it is determined in step S305 that the Nth flow rate is smaller than the measured intake air amount, the process proceeds to step S306, and if the Nth flow rate is greater, the process proceeds to step S307, where the measured intake air amount and the Nth flow rate. If they match, the process proceeds to step S308.

  In step S306, the operator operates the module control panel 44 so that the measured intake air amount = Nth flow rate, and sends an instruction to the throttle actuator 3 so that the throttle valve 2 changes to the closed side. After operating the actuator 3, the process returns to the determination step S305.

  In step S307, the operator operates the module control panel 44 so that the measured intake air amount = Nth flow rate, and sends an instruction to the throttle actuator 3 so that the throttle valve 2 changes to the open side. After operating the throttle actuator 3, the process returns to the determination step S305.

  Thereafter, when the measured intake air amount = Nth flow rate, the module control panel 44 is operated to send a storage instruction signal to the Nth area toward the MCU 5, and the measured intake air amount is Nth. The detected opening of TPS2 when it coincides with the amount of intake air (FIG. 10) is stored in the Nth storage area of the EEPROM of MCU 5 as the actual TPS value corresponding to the amount of intake of the Nth valve (step S308).

Next, it is determined whether or not the value of the counter N has reached the table upper limit value (= 16) (step S309). If it is determined that N = 16 has not been reached (that is, NO), The value is incremented by “1” (step S310), and the process returns to step S304.
If it is determined in step S309 that N = 16 (that is, YES), the processing routine of FIG. 9 ends.

As a result of executing the learning process of FIG. 9, as shown in FIG. 11, a table associating the intake air amount with the reference TPS value and the actual TPS value (learning value) is obtained.
In the learning process of FIG. 9, the actual TPS values are acquired from the table of the intake air amount and the reference TPS value obtained by dividing the entire flow rate range into 16 parts, but learning in the low flow rate range is performed in order to reduce the processing man-hours. Only the processing may be executed, for example, only the first to eighth divisions of the 16 divisions in FIG.
This is because, as described above, the intake air amount and the throttle opening greatly vary particularly in the low flow rate region (low opening region).

Further, even when the learning process is executed in the entire flow rate range, only the process equal to or less than the number of table points shown in FIG. 10 (for example, only the odd number among the 16-division tables obtained) is executed and the process is omitted. The intake air amount at the reference point (between the reference points subjected to the process) may be obtained by interpolation calculation.
In this case, as a table interpolation method, a ratio obtained from the reference TPS value and the actual TPS value may be used in addition to the linear interpolation based on the general intake air amount and the TPS value.

Hereinafter, with reference to FIGS. 12 to 15, an interpolation method using the ratio obtained from the reference TPS value and the actual TPS value when only odd-numbered processing is executed in the second embodiment of the present invention. explain.
FIG. 12 is a table when learning the throttle opening, and shows a state before correction based on the ratio between the reference TPS value and the actual TPS value is executed.

FIG. 13 is an explanatory diagram showing the interpolation operation, and FIG. 14 is an explanatory diagram showing an interpolation calculation processing operation at the time of correction based on the ratio between the reference TPS value and the actual TPS value in a table.
FIG. 15 is an explanatory diagram showing a table during throttle opening learning, and shows a state after correction based on the ratio between the reference TPS value and the actual TPS value is executed.
In FIG. 15, the odd number in the bold line frame indicates the location actually measured.

In this case, for example, as shown in FIG. 12, only the odd-numbered actual TPS values are measured with respect to the table of FIG. 10 (the standard TPS value of 16 reference points is obtained), and the standard TPS value and the actual TPS value are measured. An interpolation method using a ratio obtained from the value is used.
Specifically, when the table as shown in FIG. 13 is obtained, the reference TPS values B1, B2, and B3 for the known flow rates (intake amounts) A1, A2, and A3 are all known.

In FIG. 13, it is assumed that the actual TPS values C1 and C3 for the two flow rates A1 and A3 are obtained by measurement.
At this time, in FIG. 14, the ratio X1 / X2 (= the slope of the actual TPS characteristic) between X1 (= actual TPS value C2−actual TPS value C1) and X2 (= actual TPS value C3−actual TPS value C1) is If the ratio Y1 / Y2 (= the slope of the reference characteristic) between Y1 (= reference TPS value B2−reference TPS value B1) and Y2 (= reference TPS value B3−reference TPS value B1) is considered to be equal to X1, X2 , Y1, Y2, B1 to B3, and C1 to C3 are expressed as follows.

X1 / X2 = Y1 / Y2
X1 = C3-C1
X2 = C3-C2
Y1 = B3-B1
Y2 = B3-B2

  From the above correlation, the unknown actual TPS value C2 is obtained by interpolation as shown in the following equation (2).

  C2 = (C3-C1) × (B2-B1) / (B3-B1) + C1 (2)

  In this way, by performing the interpolation operation on the measurement result of FIG. 12 using the equation (2), a table equivalent to FIG. 11 can be obtained as shown in FIG.

Further, not only the interpolation calculation method based on the ratio shown in FIG. 14, but also an interpolation calculation method based on the deviation between the reference TPS value and the actual TPS value as shown in FIG.
FIG. 16 is an explanatory diagram showing, in the form of a graph, the interpolation calculation processing operation at the time of correction based on the deviation between the reference TPS value and the actual TPS value in the second embodiment of the present invention.
FIG. 17 is an explanatory diagram showing a table at the time of throttle opening learning based on FIG. 16 and shows a state after correction based on a deviation between the reference TPS value and the actual TPS value.
In FIG. 17, the odd number in the bold line frame indicates the part actually measured.

Also in this case, it is assumed that the same information as in FIGS. 10 and 12 is obtained as described above.
Here, as shown in FIG. 16, the deviations Z1, Z2, and Z3 between the reference TPS value and the actual TPS value are considered to have a linear relationship with the flow rates (intake amounts) A1, A2, and A3. ˜Z3, A1 to A3, B1 to B3, and C1 to C3 are expressed as follows.

Z2 = (Z3-Z1) × (A2-A1) / (A3-A1) + Z1
Z1 = C1-B1
Z2 = C2-B2
Z3 = C3-B3

  From the above correlation, the unknown actual TPS value C2 is obtained by interpolation as in the following equation (3).

  C2 = (C3-B3-C1 + B1) × (A2-A1) / (A3-A1) + C1-B1 + B2 (3)

  As described above, by performing the interpolation operation on the measurement result of FIG. 12 using the expression (3), as shown in FIG. 17, a table equivalent to FIG. 11 and FIG. 15 can be acquired.

  As described above, table information (FIGS. 15 and 17) indicating the relationship between the throttle opening and the intake air amount is stored in the MCU 5 in the ETV module 1 by the interpolation calculation process. Thus, it is possible to absorb the characteristic variation among the individual ETV modules 1 and improve the controllability. Further, when a plurality of ETV modules 1 are used at the same time, it is easy to align the intake air amount of each individual.

Next, referring to the flowcharts of FIGS. 1 and 18, the ETV module 1 storing the relationship between the intake air amount, the reference TPS value, and the actual TPS value (FIGS. 11, 15, and 17) as described above is used. The intake air amount control operation of the engine 10 will be described.
Here, the table of FIG. 11 is typically used.
Therefore, FIG. 18 shows a processing procedure of the MCU 5 and the ECU 6 at the time of opening degree control of the ETV module 1 using the measurement result of FIG.

In FIG. 18, steps S401 to S404 are the same processes as steps S201 to 204 described above (see FIG. 7).
First, the ECU 6 sets the target throttle opening D2 (for example, 8 [%]) based on the accelerator opening α from the accelerator position sensor, the cooling water temperature Tw from the water temperature sensor, and the intake air amount A from the intake air sensor. ) And a drive request for the target throttle opening D2 is sent to the MCU 5 of the intake air amount control module 1 (step S401).

Subsequently, in response to the drive request from the ECU 6, the MCU 5 refers to the learned table (FIG. 11) and obtains an actual TPS value E2 for the target throttle opening D2 (8 [%]) (step S402). .
At this time, the actual TPS value E2 is obtained by interpolation (for example, linear interpolation) between table points stored in the MCU 5 in the learning process (FIG. 9).
For example, when the target throttle opening D2 is 8 [%], the actual TPS value E2 is confirmed to be 10 [%] from the table of FIG.

Next, the MCU 5 drives the throttle actuator 3 so that the detected opening actually measured by the TPS 4 coincides with the actual TPS value E2 (= 10 [%]) (step S403).
Finally, the MCU 5 determines the detected opening (= E2) of the TPS4 when the detected opening of the TPS4 coincides with the actual TPS value E2 (= 10 [%]) after the driving of the throttle valve 2 is completed. The throttle opening corresponding to the opening D2 (= 8 [%]) is input to the ECU 6 (step S404), and the process of FIG. 18 is terminated.

  As described above, the table of the intake air amount, the reference TPS value, and the actual TPS value (FIG. 11) is stored in the ETV module 1, and correction processing based on the relationship of FIG. Compared to the conventional control based on the opening, the variation among the individual intake air amount control modules 1 due to the variation in the relationship between the throttle opening and the intake air amount due to processing variations, etc. is suppressed. Highly reliable control of the engine 10 can be easily realized.

  In the second embodiment of the present invention, a correspondence table between the reference TPS value and the actual TPS value as shown in FIG. 11 is stored in the MCU 5, and communication between the MCU 5 and the ECU 6 regarding the throttle opening is performed, and the ETV module 1 and the engine 10 are controlled, a table created based on the relationship between the reference flow rate value and the actual TPS value may be stored in the MCU 5, and the ETV module 1 and the engine 10 may be controlled based on the flow rate.

Further, the predetermined value of the measured intake air amount is set by table reference points over the entire flow rate range of the throttle valve 2 as shown in FIG. 11 (or FIG. 15, FIG. 17). As a result, the correction accuracy can be improved and the intake air amount control can be improved.
Further, if the table reference point used in FIG. 9 is set only in the low flow rate region of the throttle valve 2, the number of processing steps is reduced, so that the learning process can be executed efficiently.
In this case, learning information (table) with a certain degree of reliability can be obtained, so that the control accuracy during normal operation is not greatly impaired.

Embodiment 3 FIG.
In the second embodiment, the relationship between the intake air amount, the reference TPS value, and the actual TPS value is stored as a table over the entire flow rate region including the minimum flow rate, but the intake air amount, the reference TPS value, and the actual TPS value are May be stored as a table composed of two reference points including the minimum flow rate.

Hereinafter, an internal combustion engine control apparatus according to Embodiment 3 of the present invention using a two-point table including the minimum flow rate will be described with reference to FIGS. 19 to 22 together with FIGS.
Also in this case, the device configuration and the functional configuration of the MCU 5 during normal operation and when measuring the intake air amount of the ETV module 1 are the same as those described above (see FIGS. 1 to 3).

FIG. 19 is a flowchart showing a processing procedure when measuring the intake air amount (during throttle opening learning) of the ETV module 1 according to Embodiment 3 of the present invention.
20 and 21 are explanatory diagrams showing tables corresponding to the above-described FIGS. 10 and 11, and FIG. 20 is a table of known reference TPS values before executing the learning process (FIG. 19). 21 is a table of actual TPS values after the learning process (FIG. 19) is executed.
FIG. 22 is a flowchart showing a control process during normal operation after completion of the learning process (FIG. 19).

  20 and 21, each TPS value is set for a minimum flow rate and an arbitrary flow rate R [g / sec] in the low opening range. Each TPS value corresponding to the minimum flow rate in FIGS. 20 and 21 is the same as the table values in FIGS. 5 and 6 described above.

First, a learning process according to the third embodiment of the present invention will be described with reference to FIG. 2 and FIGS.
The processing procedure shown in FIG. 19 is executed in the device configuration diagram of FIG.
In FIG. 19, steps S501 to S507 are the same as steps S101 to S107 described above (see FIG. 4), and steps S508 to S512 correspond to steps S103 to S107.

  First, the operator connects an external device to the ETV module 1 (step S501), drives the vacuum pump 42 under negative pressure (step S502), and then refers to a known table (FIG. 20) to detect the detected opening of the TPS4. The module control panel 44 is operated so that the reference TPS value at the minimum flow rate (1.7 [%]) is reached, an opening amount instruction is sent to the MCU 5, and the throttle actuator 3 is operated (step S503).

Next, the minimum flow rate is compared with the current measured intake air amount with reference to the table of FIG. 20, and the magnitude relationship between the two is determined (step S504).
If it is determined in step S504 that the intake air amount measurement value> the minimum flow rate, the process proceeds to step S505. If the intake air amount measurement value <the minimum flow rate, the process proceeds to step S506. If the intake air amount measurement value = the minimum flow rate, the process proceeds to step S507. move on.
In steps S505 and S506, the operator operates the module control panel 44 to send an opening amount instruction to the MCU 5 so that the measured intake air amount = the minimum flow rate, and operates the throttle actuator 3 to open the throttle valve 2. The degree is controlled, and the process returns to the determination step S504.

  Thereafter, when the measured intake air amount = the minimum flow rate, a storage instruction signal to the minimum flow rate storage area is sent from the module control panel 44 to the MCU 5, and the TPS 4 when the measured intake air amount = the minimum flow rate is obtained. (For example, 3.1 [%]) is stored in the MCU 5 of the ETV module 1 as an actual TPS value (step S506).

  Next, referring to the known table (FIG. 20) again, the module control panel 44 so that the detected opening of the TPS 4 becomes the reference TPS value at the flow rate R (for example, 13.00 [g / sec]). Is operated to send an opening amount instruction to the MCU 5 to operate the throttle actuator 3 (step S508).

Subsequently, the flow rate R is compared with the current measured intake air amount to determine the magnitude relationship between the two (step S509).
If the intake air measurement value> flow rate R as a result of the determination in step 5509, the process proceeds to step S510. If the intake air measurement value <flow rate R, the process proceeds to step S511. If the intake air measurement value = flow rate R, the process proceeds to step S512. move on.

  In steps S510 and S511, the operator operates the module control panel 44 so that the measured intake air amount = the flow rate R, sends an opening amount instruction to the MCU 5, operates the throttle valve 2, and opens the opening of the throttle valve 2. And return to the determination step S509.

  Thereafter, when the measured intake air amount = flow rate R, a storage instruction signal to the minimum flow rate storage area is sent from the module control panel 44 to the MCU 5, and TPS 4 when the measured intake air amount = flow rate R is reached. The detected opening (for example, 12.1 [%]) is stored in the MCU 5 of the ETV module 1 as an actual TPS value for the flow rate R (step S512), and the processing routine of FIG.

By executing the above process, a table composed of two reference points indicating the relationship between the intake air amount and the actual TPS value can be obtained as shown in FIG.
In the case of the table of FIG. 21, it can be acquired with a smaller number of processing times compared to the table described above (see FIG. 11).

Next, referring to the flowcharts of FIGS. 1 and 22, the engine 10 using the ETV module 1 storing the table (relationship between the intake air amount, the reference TPS value, and the actual TPS value) after learning (FIG. 21). The intake air amount control operation will be described.
FIG. 22 shows a processing procedure performed by the MCU 5 and the ECU 6 and is executed using the measurement result of FIG. 21 in the apparatus configuration of FIG.

22, steps S601 and S603 to S605 are the same processes as steps S201 to S204 (or steps S401 to 404 in FIG. 18) described above (see FIG. 7), respectively.
First, the ECU 6 calculates a target throttle opening D3 (for example, 8 [%]) based on the accelerator opening α from the accelerator position sensor and the coolant temperature Tw from the water temperature sensor, and calculates the calculated target throttle opening D3. Is requested to the MCU (step S601).

Next, the reference TPS value (10.0 [%]) at the flow rate R is compared with the target throttle opening D3 to determine whether or not the reference TPS value is larger than the target throttle opening D3 (step). S602).
If it is determined in step S602 that the reference TPS value at the flow rate R is larger than the target throttle opening D3 (that is, YES), the process proceeds to steps S603 to S605, where the reference TPS value at the flow rate R is the target throttle value. If it is determined that the degree of opening is less than D3 (that is, NO), the process proceeds to steps S606 and S607.

In step S603, the MCU 5 determines an actual TPS value E3 corresponding to the target throttle opening D3 with reference to the table of FIG. 21 in response to the control request by the target throttle opening D3 from the ECU 6.
At this time, the actual TPS value E3 is obtained by linearly interpolating the two actual TPS values of the minimum flow rate and the flow rate R stored in the MCU 5.

  For example, when the target throttle opening D3 is 8 [%], it corresponds to the value 8 [%] within the range of the reference TPS value 1.7 [%] to 10.0 [%] from the table of FIG. The actual TPS value E3 to be obtained is obtained as 10 [%] by performing linear interpolation within the range of the actual TPS value 3.1 [%] to 12.1 “%”.

Subsequent to step S603, the MCU 5 drives the throttle actuator 3 so that the detected opening of the TPS 4 becomes the actual TPS value E3 (step S604).
Finally, the MCU 5 sets the detected opening (= E3) of the TPS4 to the target throttle opening D3 when the drive of the throttle valve 2 is completed and the relationship of the detected opening of the TPS4 = the actual TPS value E3 is satisfied. Is input to the ECU 6 as a throttle opening corresponding to (step S605), and the processing routine of FIG. 22 is terminated.

  As described above, when the target throttle opening degree D3 requested from the ECU 6 is smaller than the actual TPS value at the flow rate R, the MCU 5 uses a two-point table (TPS value) for the minimum flow rate and the arbitrary flow rate R. The actual TPS value E3 corresponding to the target throttle opening D3 is obtained by linear interpolation, and the intake air amount is controlled using the actual TPS value E3 as the corrected target opening.

On the other hand, when the process proceeds from determination step S602 to step S606, the MCU 5 drives the throttle actuator 3 so that the detected opening degree of the TPS 4 becomes the target throttle opening degree D3.
Finally, the MCU 5 sets the detected opening (= D3) of the TPS4 to the target throttle opening when the drive of the throttle valve 2 is completed and the relationship of the detected opening of the TPS4 = the target throttle opening D3 is satisfied. The throttle opening corresponding to D3 is input to the ECU 6 (step S607), and the processing routine of FIG. 22 is terminated.

  Thus, when the target throttle opening D3 is equal to or greater than the actual TPS value at the flow rate R, the MCU 5 controls the intake air amount using the target throttle opening D as it is as the actual target opening.

  As described above, assuming that the flow rate when the throttle opening degree indicates when the throttle valve 2 is fully open is unchanged, the opening degree when the throttle is fully open (actual TPS value) and the opening degree when the flow rate is R. Linear interpolation between two points with (actual TPS value) may be used.

Hereinafter, an interpolation calculation method using the opening degree (TPS value) when fully opened will be described with reference to the explanatory diagram of FIG.
In FIG. 23, the reference TPS values B1 and B3 are known with respect to the known intake air amounts A1 (arbitrary flow rate R) and A3 (full open flow rate), and the actual TPS value C3 corresponding to the intake air amount A3 (full open flow rate). Is also known.

  Therefore, when the actual TPS value C1 corresponding to the intake air amount A1 (arbitrary flow rate R) is obtained by measurement, if the unknown actual TPS value C2 for the indicated opening B2 is obtained by interpolation, the actual TPS value C2 is as follows: (4).

  C2 = (C3-C1) × (B2-B1) / (B3-B1) + C1 (4)

  As described above, the table (FIG. 21) of the flow rate, the reference TPS value, and the actual TPS value is created for only two points and is learned and stored in the ETV module 1 in advance, and the intake air amount control process based on the relationship of FIG. As a result, the variation between the throttles due to variations in the relationship between the throttle opening and the flow rate due to processing variations, etc. is suppressed compared to the conventional throttle relative opening-based control. Quantity-based engine control can be easily realized.

Further, two arbitrary points are set as reference points in the table (FIG. 21), and the actual TPS value E3 (corrected target opening) corresponding to the target throttle opening D3 is a linear connecting the predetermined values (arbitrary two points). Since (linear) approximation can be obtained, the number of learning processing steps can be reduced without significantly impairing the reliability of learning correction.
In addition, since the predetermined value of the intake air amount measurement value includes the minimum flow rate adjusted by the throttle valve 2, it is possible to improve the reliability of the intake air amount control particularly in a low flow rate range in which variations tend to occur.

Embodiment 4 FIG.
As a table (relationship between the flow rate, the reference TPS value, and the actual TPS value) that is learned and stored in the MCU 5 in the ETV module 1, in the second embodiment, a reference for N (= 1 to 16) reference points. A table (FIG. 11) based on the characteristics (FIG. 10) is created. In the third embodiment, a table (FIG. 21) based on the reference characteristics (FIG. 20) regarding two points including the minimum flow rate is created. On the other hand, after learning and storing only two points including the minimum flow rate, an interpolation calculation based on the reference characteristics and the measurement results of the two points is executed in the MCU 5 so that N references similar to those in FIG. 11 are finally obtained. A table for points may be created.

A description will now be given of a fourth embodiment of the present invention in which a table for an arbitrary plurality of points is created from a table for two points and stored.
Also in this case, the device configuration and the functional configuration of the MCU 5 are the same as those described above (see FIGS. 1 to 3).
Further, the throttle opening degree learning process according to the fourth embodiment of the present invention is executed in the same manner as the processing procedure of the third embodiment (steps S501 to S512 in FIG. 19).

In the fourth embodiment of the present invention, a plurality of table points are created from the reference TPS value at the minimum flow rate and the flow rate R by interpolation using a ratio.
Hereinafter, the table creation method based on the interpolation calculation according to the fourth embodiment of the present invention will be described with reference to FIGS. 24 to 26 together with FIGS. 1 to 3 and FIG.
Here, for example, in the case where the reference TPS values in the table (FIG. 10) used in the second embodiment are obtained in advance, only two actual TPS values are measured and then obtained from the reference TPS values. An interpolation calculation method using the obtained ratio will be described.

First, when the table as shown in FIG. 24 is obtained, the reference TPS values B1, B2, B3, and B4 are known for the intake air amounts A1, A2, A3, and A4.
In FIG. 24, when the actual TPS values C1 and C4 for the intake air amounts A1 (minimum flow rate) and A4 (arbitrary flow rate R) are obtained by measurement (learning), the actual TPS values C2 and C3 for the intake air amounts A2 and A3 are unknown. It is.

Here, as shown in FIG. 25, in the throttle opening (horizontal axis) direction, parameters Y1, Y2, and Y3 for the characteristic of the reference TPS value and parameters X1, X2, and X4 for the characteristic of the actual TPS value are shown in FIG. In relation to the reference TPS values B1 to B4 and the actual TPS values C1 to C4 in 24, the ratio of X1 and X3 is considered to be equal to the ratio of Y1 and Y3, and the ratio of X2 and X3 is It is considered to be equal to the ratio of Y2 and Y3.
Therefore, the correlation between X1 to X3, Y1 to Y3, B1 to B4, and C1 to C4 is expressed as follows.

X1 / X3 = Y1 / Y3
X1 = C2-C1
X3 = C4-C1
Y1 = B2-B1
Y3 = B4-B1
X2 / X3 = Y2 / Y3
X2 = C3-C1
X3 = C4-C1
Y2 = B3-B1
Y3 = B4-B1

  From the above correlation, the unknown actual TPS values C2 and C3 are obtained by interpolation calculation as in the following formulas (5) and (6).

C2 = (C4-C1) × (B2-B1) / (B4-B1) + C1 (5)
C3 = (C4-C1) × (B3-B1) / (B4-B1) + C1 (6)

Further, as described above, the flow rate when the throttle is fully opened is regarded as the same in both the reference characteristic and the actual TPS characteristic, and the interpolation calculation is performed in the same manner as described above for the region of the flow rate R or more. be able to.
As a result of interpolating the measurement values in FIG. 24 by the interpolation calculation of Expression (5) and Expression (6), a plurality (16 points) of tables are acquired as shown in FIG.

Further, instead of the interpolation calculation based on the ratio as described above, an interpolation calculation based on the deviation can be applied as shown in FIGS. 27 to 29 below.
That is, when the same information as in FIG. 24 is obtained in advance, as shown in FIG. 27, deviations Z1, Z2, and Z4 between the reference TPS value and the actual TPS value and the intake air amounts A1, A2, and A4 are obtained. Assuming that the deviations Z1, Z3, Z4 and the intake air amounts A1, A3, A4 are in a linear relationship, Z1 to Z4, A1 to A4, B1 to B4, C1 The interrelationship of C4 is expressed as follows.

Z2 = (Z4-Z1) × (A2-A1) / (A4-A1) + Z1
Z1 = C1-B1
Z2 = C2-B2
Z4 = C4-B4
Z3 = (Z4-Z1) × (A3-A1) / (A4-A1) + Z1
Z1 = C1-B1
Z3 = C3-B3
Z4 = C4-B4

  From the above correlation, the unknown actual TPS values C2 and C3 are obtained by interpolation calculation as in the following formulas (7) and (8).

C2 = (C4-B4-C1 + B1) × (A2-A1) / (A4-A1) + C1-B1 + B2 (7)
C3 = (C4-B4-C1 + B1) × (A3-A1) / (A4-A1) + C1-B1 + B3 (8)

Further, as described above, the region where the flow rate is equal to or greater than the flow rate R can be regarded as the same when the throttle is fully open, both in the reference characteristic and in the actual TPS characteristic, and interpolation calculation can be performed in the same manner as described above. it can.
In this way, as a result of interpolating the measurement result by the interpolation calculation of Expression (7) and Expression (8), as shown in FIG. 28, a table including 16 reference points similar to the above (see FIG. 11) is obtained. Can do.

By using the above interpolation method, it is possible to improve the intake air amount control accuracy even when measuring two points, as in the case of measuring three or more points.
That is, as described above, table information indicating the relationship between the throttle opening and the intake air amount is stored for each individual ETV module 1, so that the characteristic variation among each individual is absorbed by using the table information. Thus, controllability can be improved.
In particular, when a plurality of ETV modules 1 are used at the same time, it is easy to make the flow rate of each individual uniform.

Next, an intake air amount control operation of the engine 10 according to the fourth embodiment of the present invention will be described with reference to the flowchart of FIG.
Also in this case, the relationship between the flow rate, the reference TPS value, and the actual TPS value (see FIG. 26 or FIG. 28) is learned and stored in the ETV module 1, and the ECU 6 uses the ETV module 1 after the learning process. Intake amount control (throttle opening control) is executed.

The processing routine of FIG. 29 is executed by the MCU 5 and the ECU 6 in the apparatus configuration shown in FIG.
In FIG. 29, steps S701 to S704 are the same processing as steps S401 to 404 described above (see FIG. 18).

  First, when the ECU 6 requests the flow rate of the target throttle opening D4 (for example, 8 [%]) from the MCU 5 (step S701), the MCU 5 responds to the actual throttle opening D4 corresponding to the target throttle opening D4. A TPS value E4 is obtained (step S702).

At this time, the MCU 5 obtains the actual TPS value E4 using the learned table (FIG. 26) stored in the EEPROM.
For example, as described above, when the target throttle opening D4 is 8 [%], the actual TPS value E4 is obtained as 10 [%] by linear interpolation based on the table of FIG.

Subsequently, the MCU 5 drives the throttle actuator 3 so that the detected opening of the TPS 4 coincides with the actual TPS value E4 (step S703).
Finally, the MCU 5 sets the detected opening (= E4) of the TPS4 to the target throttle opening when the detected opening = actual TPS value E4 (= 10 [%]) is satisfied after the driving of the throttle valve 2 is completed. The throttle opening corresponding to D4 (= 8 [%]) is input to the ECU 6 (step S704), and the process of FIG. 29 is terminated.

As described above, the learning results of two points including the minimum flow rate are stored in the MCU 5 in the ETV module 1, and the interpolation calculation processing based on the relationship between the reference characteristic and the two points of measurement results is performed in the MCU 5. By executing (FIG. 19), the same table as described above (see FIG. 11) can be acquired.
Also in this case, as compared with the control based on the throttle relative opening, the variation among the individual ETV modules 1 due to the variation in the relationship between the throttle opening and the intake air amount due to processing variations is suppressed, and the opening-intake air amount. The base engine control can be easily realized.
Further, by simplifying the initial learning process for the MCU 5, it is possible to acquire a multi-point table (FIG. 11) with little effort and improve the control accuracy of the intake air amount.

That is, according to the fourth embodiment of the present invention, it is possible to use a control device for an internal combustion engine in which the relationship between the throttle opening and the actual intake air amount is clarified. In addition to the error in the relationship between the actual throttle opening and the detected opening of the TPS4, the variation among individuals of the ETV module 1 includes the variation in the relationship between the throttle opening and the intake air amount due to processing variations. It is suppressed, and accurate intake air amount control can be realized without being affected by the mounting error and processing variation.
In addition, the measurement of the relationship between the opening degree and the intake air amount is limited to a low flow rate region where the variation of the intake air amount is large, and the measurement point at the time of the learning processing is set to two points, thereby reducing the man-hour. The relationship between the intake air amount can be acquired, and the control based on the opening degree-intake air amount can be easily realized.
Further, as described above, the opening degree correction means in the MCU 5 can obtain the corrected target opening degree (actual TPS value) based on the ratio or deviation obtained from the reference characteristics.

In the first to fourth embodiments, the target throttle opening degree Do requested by the ECU 6 is corrected based on a table showing the relationship between the intake air amount stored in the MCU 5 and the reference TPS value and the actual TPS value. The intake amount is controlled by obtaining the actual TPS value corresponding to the corrected target throttle opening and operating the throttle actuator 3 so that the detected opening of the TPS 4 matches the actual TPS value. It is not limited to.
For example, based on the relationship between the intake air amount stored in the MCU 5, the reference TPS value, and the actual TPS value, the detected opening of the TPS 4 is read as the reference TPS value, and the changed target TPS value requested from the ECU 6 is the reference TPS value after the replacement. The intake air amount may be controlled by operating the throttle actuator 3 so as to coincide with the opening degree Do, and it goes without saying that the same effect as described above can be obtained.

It is a block block diagram which shows roughly the intake air amount control module of the control apparatus for internal combustion engines which concerns on Embodiment 1-4 of this invention. It is a block diagram which shows the state at the time of the intake air quantity measurement (learning) of the ETV module of the control apparatus for internal combustion engines which concerns on Embodiment 1-4 of this invention. It is a block diagram which shows the function structure of MCU5 in the ETV module which concerns on Embodiment 1-4 of this invention. It is a flowchart which shows the process sequence at the time of throttle opening learning by Embodiment 1 of this invention. It is explanatory drawing which shows the reference | standard characteristic (known relationship) of the flow volume (intake amount) applied to Embodiment 1 of this invention and the reference | standard TPS value with a table. It is explanatory drawing which shows the relationship between the intake air amount after learning by Embodiment 1 of this invention, a reference | standard TPS value, and an actual TPS value with a table. 3 is a flowchart showing an intake air amount control operation of the MCU and ECU during normal operation according to Embodiment 1 of the present invention. It is explanatory drawing which shows the other interpolation calculation processing operation by Embodiment 1 of this invention with a table. It is a flowchart which shows the process sequence at the time of throttle opening learning by Embodiment 2 of this invention. It is explanatory drawing which shows the reference | standard characteristic of the intake air amount and reference | standard TPS value which are applied to Embodiment 2 of this invention with a table. It is explanatory drawing which shows the relationship between the intake air amount after learning by Embodiment 2 of this invention, a reference | standard TPS value, and an actual TPS value with a table. It is explanatory drawing which shows the table at the time of the other throttle opening learning by Embodiment 2 of this invention, and has shown the state before the interpolation calculation process based on the ratio of a reference | standard TPS value and an actual TPS value. It is explanatory drawing which shows the interpolation calculation processing operation by Embodiment 2 of this invention with a table. It is explanatory drawing which shows the interpolation calculation processing operation at the time of the correction | amendment based on the ratio of the reference | standard TPS value and real TPS value by Embodiment 2 of this invention with a graph. It is explanatory drawing which shows the table at the time of throttle opening learning by Embodiment 2 of this invention, and has shown the state after correction | amendment based on the ratio of reference | standard TPS value and real TPS value. It is explanatory drawing which shows the interpolation calculation processing operation at the time of the correction | amendment based on the deviation of the reference | standard TPS value and actual TPS value by Embodiment 2 of this invention with a graph. It is explanatory drawing which shows the table at the time of throttle opening learning by Embodiment 2 of this invention, and has shown the state after correction | amendment based on the deviation of a reference | standard TPS value and an actual TPS value. 7 is a flowchart showing an intake air amount control operation of an MCU and an ECU during normal operation according to Embodiment 2 of the present invention. It is a flowchart which shows the process sequence at the time of throttle opening learning by Embodiment 3 of this invention. It is explanatory drawing which shows the reference | standard characteristic of the intake air amount and reference | standard TPS value which are applied to Embodiment 3 of this invention with a table. It is explanatory drawing which shows the relationship between the intake air amount after learning by Embodiment 3 of this invention, a reference | standard TPS value, and an actual TPS value with a table. It is a flowchart which shows the intake air amount control operation | movement of MCU and ECU at the time of normal driving | operation by Embodiment 3 of this invention. It is explanatory drawing which shows the other interpolation calculation processing operation by Embodiment 3 of this invention with a table. It is explanatory drawing which shows the interpolation calculation processing operation by Embodiment 4 of this invention with a table. It is explanatory drawing which shows the interpolation calculation processing operation at the time of the correction | amendment based on the ratio of the reference | standard TPS value and real TPS value by Embodiment 4 of this invention with a graph. It is explanatory drawing which shows the table at the time of throttle opening learning after the interpolation calculation based on the ratio by Embodiment 4 of this invention. It is explanatory drawing which shows the interpolation calculation processing operation at the time of the correction | amendment based on the deviation of the reference | standard TPS value and actual TPS value by Embodiment 4 of this invention with a graph. It is explanatory drawing which shows the table at the time of throttle opening learning after the interpolation calculation based on the deviation by Embodiment 4 of this invention. It is a flowchart which shows the intake air amount control operation | movement of MCU and ECU at the time of normal driving | operation by Embodiment 4 of this invention. It is explanatory drawing which shows the relationship between a general intake air amount, a reference | standard TPS characteristic, and an actual TPS characteristic with a graph. It is explanatory drawing which shows the relationship between a general intake air amount, a reference | standard TPS characteristic, and an actual TPS characteristic with the graph which paid its attention only to the low flow area.

Explanation of symbols

  1 ETV module (intake air amount control module), 2 throttle valve (intake air amount adjusting means), 3 throttle actuator (drive means), 4 TPS (throttle opening sensor) (opening degree detecting means), 5 MCU (intake air amount module controller) Unit) (controller), 6 ECU (engine control unit), 10 engine, 42 vacuum pump (external device), 43 intake air measuring device (external device), 44 module control panel (external device), 50 EEPROM (memory element) , 51 Opening storage means, 52 Opening reference value storage means, 53 Control unit (opening comparison means, opening correction means), Do target opening.

Claims (9)

An ECU for controlling the internal combustion engine;
And a intake air amount control module for controlling the amount of intake air to the internal combustion engine,
The intake air amount control module includes:
An intake air amount adjusting means for adjusting the intake air amount;
An opening degree detecting means for detecting an opening degree of the intake air amount adjusting means;
Driving means for driving the intake air amount adjusting means;
A controller for controlling the driving means,
The controller is a control device for an internal combustion engine that controls the opening degree of the intake air amount adjusting means by controlling the driving means based on the detected opening degree of the opening degree detecting means,
The controller is
A storage element for storing control information for the driving means;
In order to measure the intake air amount passing through the intake air amount control module when learning the relationship between the opening degree of the intake air amount adjusting means and the intake air amount to the internal combustion engine in the intake air amount control module, the intake air amount control An opening degree storage means for storing the detected opening degree of the opening degree detecting means when the measured value of the intake air amount by an external device connected to the module indicates a predetermined value;
Opening reference value storage means for storing the opening reference value of the intake air amount adjusting means obtained from a predetermined reference characteristic in the storage element;
An opening degree comparing means for comparing the detected opening degree stored in the storage element and the opening degree reference value;
An opening degree correcting means for correcting a target opening degree of the intake air amount adjusting means based on a comparison result by the opening degree comparing means ;
The drive means is controlled so that the target opening corrected by the opening correction means matches the opening of the intake air amount adjusting means, and the intake air amount is based on the comparison result by the opening comparing means. ECU input opening correction means for correcting the opening of the adjustment means ,
The opening degree storage means and the opening degree reference value storage means execute a storage process when the external device is installed in place of the internal combustion engine for the intake air amount control module,
When the internal combustion engine is installed in place of the external device, the intake air amount control module is configured such that the target opening degree corrected by the opening degree correcting means matches the opening degree of the intake air amount adjusting means. In addition, the control device for the internal combustion engine is configured to control the drive means and to input the opening degree corrected by the ECU input opening degree correction means to the ECU .   2. The internal combustion engine control device according to claim 1, wherein the predetermined value of the measured intake air amount is set to a minimum flow rate that can be adjusted by the intake air amount adjusting means.   The control apparatus for an internal combustion engine according to claim 1, wherein the predetermined value of the intake air amount measurement value is set by a table reference point.   4. The control apparatus for an internal combustion engine according to claim 3, wherein the table reference point is set in an entire flow rate range of the intake air amount adjusting means.   The control device for an internal combustion engine according to claim 3, wherein the table reference point is set in a low flow rate region of the intake air amount adjusting means.   2. The control device for an internal combustion engine according to claim 1, wherein the predetermined value of the measured intake air amount is set to two arbitrary flow rate values.   The control apparatus for an internal combustion engine according to claim 6, wherein the opening degree correction means obtains the corrected target opening degree by linear approximation connecting the two arbitrary points.   The control device for an internal combustion engine according to any one of claims 3 to 7, wherein the predetermined value of the intake air amount measurement value includes a minimum flow rate adjusted by the intake air amount adjusting means.   The control device for an internal combustion engine according to any one of claims 1 to 7, wherein the opening degree correction means obtains the corrected target opening degree based on a ratio obtained from the reference characteristic. .

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