JPH11294216A - Engine control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce signal lines between detecting means and a control box and to simplify an arrangement structure by arranging an intake pressure detecting means and an intake pipe wall temperature detecting means respective ly on a substrate in the control box integrated with an intake pipe wall. SOLUTION: A throttle valve and an injector are fitted to the throttle body 6a of an intake pipe 6 connected to the intake port of an engine. An erect wall 51 and multiple tubular walls 52, 53 are integrally molded on the wall face of the throttle body 6a respectively to form a control box 50 storing a control device 15. The substrate 55 of the control device 15 is fixed to the erect wall 51 by screws 57 via vibrationproof rubbers 56. A power circuit 15a and a microcomputer 15d are arranged on the substrate 55, an intake pipe negative-pressure sensor 21 and an intake pipe wall temperature detecting means 24 are arranged on the lower face of the substrate 55, and an outside air temperature detecting means 23 is arranged on the upper face of the substrate 55.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a control device for an engine in which fuel is injected into an intake pipe.

[0002]

2. Description of the Related Art Conventionally, in an engine of the type in which fuel is injected into an intake pipe, an air-fuel ratio sensor for detecting an air-fuel ratio (A / F) of exhaust gas after combustion is provided, and a fuel injection amount is set so as to reach a target air-fuel ratio. There is known a fuel injection control system in which feedback control is performed to improve engine performance, exhaust gas characteristics, and fuel efficiency. In this scheme, A
When the / F changes from the lean side to the rich side, the fuel injection amount is controlled to be reduced. With this control, the A / F gradually changes to the lean side, and when the A / F changes from the rich side to the lean side, the fuel injection amount is reduced. By controlling the fuel injection amount to be increased, the fuel injection amount is controlled so as to achieve the target A / F.

[0003]

In the above-mentioned air-fuel ratio control, if the intake air amount can be accurately calculated and the fuel injection amount can be managed according to the intake air amount, the current air-fuel ratio can be reduced to the target air-fuel ratio. Although it can be adjusted to the fuel ratio, in practice, the fuel injection amount and the intake air amount change for various reasons, so that a deviation occurs between the current air-fuel ratio and the target air-fuel ratio. Because the fuel injected into the intake pipe,
Not all of the fuel enters the combustion chamber, part of the fuel adheres to the intake pipe wall, and the amount of fuel that adheres to the intake pipe wall is reduced by the evaporation time constant determined by the engine operating condition and the intake pipe wall temperature. The amount of fuel adhering to the intake pipe wall changes according to the operating state of the engine, and the amount of intake air varies depending on the environment around the engine such as intake air temperature and atmospheric pressure (change in air density). It also fluctuates due to aging of the engine itself, such as valve timing and valve timing.

In order to solve this problem, if the A / F deviation is eliminated in the conventional feedback control, a large number of sensors and control maps are required, and the control becomes complicated, resulting in poor responsiveness. Become
There is a problem that high-precision air-fuel ratio control cannot be performed. In addition, since there is a dead time until the injected fuel enters the combustion chamber, control responsiveness deteriorates during engine transition when the throttle opening greatly changes, and high-precision air-fuel ratio control cannot be performed. There is a problem that.

To solve this problem, the present inventor has
A separate application has been filed for a fuel injection control device for an engine capable of performing high-precision air-fuel ratio control by simple control using a minimum number of sensors based on intake pressure detection means and intake pipe wall temperature detection means. However, how to reduce the number of signal lines between these detection means and the control box and how to provide a simple arrangement structure have become major issues.

The present invention has been made to solve the above-mentioned problem, and provides an engine control device capable of reducing the number of signal lines between a detection means and a control box and having a simple arrangement structure. The purpose is to:

[0007]

According to a first aspect of the present invention, an injector 13 and a throttle valve 12 disposed in an intake pipe 6 and a control box integrated with an intake pipe wall are provided. 50, a substrate 55 fixed in the control box, an intake pressure detecting means 21 disposed on the substrate and detecting the intake pressure downstream of the throttle valve, and an intake pipe wall temperature detecting the intake pipe wall temperature. And a detecting means (24).
The invention described in claim 1 is characterized in that an elastic member 59 is mounted between the intake pressure detecting means 21 and an intake pipe wall in claim 1, and the invention described in claim 3 is that in the throttle described in claim 1, The valve (12) is brought close to the engine intake port (1a), and the intake port and the intake pressure detection means (21) are connected by a detection pipe (64). An intake pipe wall temperature detecting means 24 is disposed on the intake pipe wall, and a heat conductive resin 60
The invention according to claim 5 is characterized in that in the invention according to claims 1 to 4, an outside air temperature detecting means 23 arranged on the substrate 55 and detecting an outside air temperature is provided. According to a sixth aspect of the present invention, in any of the first to fifth aspects, the substrate 55 is fixed to the control box 50 via an anti-vibration rubber 56. The control box 50 is filled with a mold resin 61. Note that the numbers added to the above configuration are compared with the drawings for easy understanding of the present invention, and the present invention is not limited thereto.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 14 show an example of a fuel injection control device to which the present invention is applied.

FIG. 1 is a configuration diagram of the engine. The four-stroke engine 1 includes a cylinder body 2, a crankshaft 3,
The engine includes a piston 4, a combustion chamber 5, an intake pipe 6, an intake valve 7, an exhaust pipe 8, an exhaust valve 9, an ignition plug 10, and an ignition coil 11. A throttle valve 12 is provided in the intake pipe 6. An injector 13 is provided upstream of the valve 12, and a control box containing a control device 15 is provided on a wall surface of the intake pipe 6. The injector 13 is connected to a fuel tank 19 via a pressure regulating valve 16, a fuel pump 17 driven by an electric motor, and a filter 18.

The control unit 15 receives detection signals from various sensors for detecting the operating state of the engine 1. That is, as a sensor, a crank angle sensor (engine speed detecting means) 20 for detecting the rotation angle of the crankshaft 3,
An intake pipe negative pressure sensor (intake pressure detection means) 21 for detecting an intake pressure in the intake pipe 6, and an outside air temperature detection means 23 (temperature) disposed in a control box 50 of the control device 15 for detecting an outside air temperature around the engine. A sensor 1), and an intake pipe wall temperature detecting means 24 (temperature sensor 2) disposed in the control box 50 and detecting the wall temperature of the intake pipe 6 are provided. The control device 15 performs arithmetic processing on the detection signals of these sensors, and transmits control signals to the injector 13, the fuel pump 17, and the ignition coil 11. As shown in FIG. 2, the control device 15 includes a power supply circuit 1 connected to a battery.
5a, an input I / F 15b, a microcomputer 15d having a non-volatile memory 15c, and an output I / F 15e. The temperature sensors 1, 2 and the intake pipe negative pressure sensor 21 are disposed in a control box 50 of the control device 15 and detected. The signal is input to the input I / F 15b.

FIG. 3 is a block diagram showing a configuration of a control unit relating to the injector performed in the microcomputer 15d of FIG. A control unit configured to calculate an engine speed from the crank angle signal;
A rotation fluctuation calculator 28 that calculates the rotation fluctuation of the crankshaft 3 based on the crank angle signal, an intake pressure information processor 26 that processes the intake pressure signal into a plurality of data, and signals from the temperature sensors 1 and 2. A temperature information processing unit 35 for creating an engine temperature and an intake pipe wall temperature, and a model base control unit 27 are provided. The model base control unit 27 includes an engine speed, rotation fluctuation, intake pressure information, an engine temperature, and an intake pipe wall temperature. Is processed by a method described later, and an injection signal is output to the injector 13.

FIG. 4 is a block diagram showing the configuration of the intake pressure information processing section 26 of FIG. Inlet pressure information processing unit 26
Has an average pressure calculation unit 26a for calculating an average intake pressure during one stroke from an intake signal and a minimum pressure calculation unit 26b for calculating a minimum intake pressure during one stroke, and sends both signals to the model base control unit 27a. Output.

FIG. 5A shows the temperature information processing section 35 shown in FIG.
FIG. 5B is a diagram for explaining the calculation of the engine temperature. The engine temperature is calculated by the engine temperature calculation unit 35 a based on the signals from the temperature sensors 1 and 2, and output to the model base control unit 27. As shown in FIG. 5B, the engine temperature is estimated and calculated based on the intake pipe wall temperature by the temperature sensor 2 and the temperature around the engine by the temperature sensor 1. The signal of the temperature sensor 2 is output as it is to the model base control unit 27 as the intake pipe wall temperature.

FIG. 6 is a block diagram showing the structure of the model base control unit 27 shown in FIG. Model base control unit 27
Is an intake air amount calculation unit 30 for calculating an intake air amount from intake pressure information and an engine speed, and an intake fuel amount for calculating an intake fuel amount from an engine speed, an intake air amount, an intake pipe wall temperature, and an injection fuel amount. A calculating unit 31; an estimated air-fuel ratio calculating unit 32 for calculating an estimated air-fuel ratio from the calculated estimated intake air amount and the estimated intake fuel amount; and a target air-fuel ratio from the estimated intake air amount, engine speed, rotation fluctuation, and engine temperature. Target air-fuel ratio calculation unit 33 that calculates the target air-fuel ratio and the internal F / B that controls the fuel injection amount according to the difference between the calculated target air-fuel ratio and the estimated air-fuel ratio
A (feedback) calculation unit 34 is provided. The contents of each calculation unit will be described.

The cause of the deviation between the current exhaust air-fuel ratio and the estimated air-fuel ratio is a deviation due to an environmental change (change in air density) around the engine such as intake air temperature or atmospheric pressure.
The shift is caused by a shift due to a change over time of the engine itself such as a valve timing, a shift due to a change in an evaporation time constant of fuel adhering to the intake pipe 6, and a shift due to a change in a rate of fuel adhering to the intake pipe 6. Therefore, the intake air amount, the intake fuel amount, and the target air-fuel ratio are modeled, and the A / F deviation is calculated as a change amount of each of the four causes.

FIG. 7 shows a model of the intake air amount calculating section 30 of FIG. 6, and is a schematic configuration diagram of a fuzzy neural network for obtaining an estimated intake air amount. The fuzzy neural network has a hierarchical structure with six processing layers.
Consisting of the antecedent part from the first layer to the fourth layer and the consequent part of the fifth and sixth layers, the average intake pressure, minimum intake pressure and engine speed during one stroke input in the antecedent part are as follows: Fuzzy inference is made as to how much the rule conforms to the predetermined rule, and an estimated intake air amount is obtained by using the value obtained in the antecedent using the centroid method in the consequent.

As shown in FIG. 8, the above-mentioned rules include three operating conditions A corresponding to the average intake pressure during one stroke, the minimum intake pressure during one stroke, and the engine speed, which are input information.
_{11, A 21, A 31,} A 12, A 22, A 32 and A _13, A _23, A
_{Assuming 33} , a total of 9 operating conditions and 27 conclusions R ¹
Performed by a combination of a to R ^27. FIG. 10 is a diagram showing the rules in the form of a three-dimensional map, in which the vertical axis represents the operating conditions A ₁₂ , A ₂₂ and A _{32 with} respect to the average intake pressure during one stroke.
Is the operating condition A ₁₁ with respect to the engine speed on the horizontal axis,
A ₂₁ , A ₃₁ and operating conditions A ₁₃ , A ₂₃ , A ₃₃ for the average intake pressure during one stroke are shown.
The three-dimensional space formed by the average intake pressure and the minimum intake pressure between strokes is divided into two to correspond to each operating condition.
Seven regions indicates conclusions R ¹ to R ^27.

[0018] In this case, the operating conditions A ₁₁ is the engine speed is "low speed region", A ₂₁ is "medium speed range", A ₃₁ is "high rpm", the operating conditions A ₁₂ is the average between one stroke intake pressure is "low", a ₂₂ is "moderate", a ₃₂ is "high", the operating conditions a ₁₃ are members of "low" minimum intake pressure between one stroke, a ₂₃ is "moderate", a ₃₃ is The operating condition is indicated by an ambiguous expression of “high”, and the conclusions R ^{1 to} R ²⁷ are based on the estimated intake pressure corresponding to the magnitude of the engine speed and the average intake pressure and the minimum intake pressure during one stroke. Shows the amount of air.
With these operating conditions and conclusions, the rules are, for example,
"If the engine speed is in the middle speed range, the average intake pressure during one stroke is medium, and the minimum intake pressure is medium,
The estimated intake air amount is V1. Or "The engine speed is in the high speed range, the average intake pressure during one stroke is high,
When the minimum intake pressure is high, the estimated intake air amount is V2. ”And 27 other rules.

In the first to fourth layers, the processing for the engine speed and the processing for the average intake pressure and the minimum intake pressure during one stroke are separated. The average intake pressure and the minimum intake pressure signal are input as input signals xi (i = 1 to 3), and the operation conditions A ₁₁ , A ₂₁ , A ₃₁ , A ₁₂ , A ₂₂ , A ₃₂ and A ₁₃ ,
Request contribution aij for A _23, A _33. Specifically, the contribution rate aij is obtained by the sigmoid function f (xi) shown in the equation (1).

[0020]

(Equation 1)

In the above equation, wc and wg are coefficients relating to the center value and the slope of the sigmoid function, respectively.

After calculating the contribution ratio aij in the fourth layer by the sigmoid function, the nine conclusions R ¹ to R 9 to the engine speed and the throttle opening input from the contribution ratio in the fifth layer using the equation (2). The conformity μi for R ²⁷ is determined, the normalized conformity μi is further normalized using the equation (3), and the normalized suitability is determined on the sixth layer. normalized fitness, obtains the estimated intake air amount V by taking the weighted average of the output values fi (i.e. the output value corresponding to each conclusion R ¹ to R ²⁷⁾ of the fuzzy rules.

[0023]

(Equation 2)

[0024]

(Equation 3)

[0025]

(Equation 4)

FIG. 9 is a diagram showing the correlation between the average intake pressure and the minimum intake pressure during one stroke and the intake air amount, and shows that the correlation is strong in any case. By inputting two pieces of intake pressure information having a strong correlation with the intake air amount, it is possible to accurately calculate the estimated intake air amount. The intake pressure information having a strong correlation with the intake air amount is not limited to this, and a difference between the maximum pressure and the minimum pressure or a pulsation frequency of the intake pressure may be used.
Alternatively, three or more pieces of information among these pieces of intake pressure information may be used. The fuzzy neural network shown in FIG. 9 is an example. For example, the estimated intake air amount is obtained by dividing the input engine speed and throttle opening into finer conditions and using 27 or more conclusions. Needless to say, such a configuration may be adopted.

FIG. 10 is a block diagram showing a learning model of the intake fuel amount calculator 31 in FIG. The evaporation time constant calculation unit 31a calculates a time constant τ at which fuel attached to the wall of the intake pipe 6 evaporates based on the engine temperature, the engine speed, and the estimated intake air amount. Fuel adhesion rate calculator 31b
Calculates the rate at which the injected fuel adheres to the wall surface of the intake pipe 6 and the throttle valve 12 based on the engine speed and the estimated intake air amount (fuel adhesion rate = x). The non-adhesion fuel calculation unit 31c calculates the non-adhesion fuel based on the calculated fuel adhesion rate x.
The amount of fuel that the input fuel injection amount directly enters the combustion chamber 5 is calculated. The attached fuel calculation unit 31d calculates the amount of fuel in which the input fuel injection amount is attached to the wall of the intake pipe 6 based on the calculated fuel attachment rate x. The amount of fuel calculated by the non-adhered fuel calculating unit 31c and the adhering fuel calculating unit 31d is calculated by the primary delay units 31e and 31f, respectively, based on the estimated evaporation time constant τ calculated by the evaporation time constant calculating unit 31a. After being approximated by the next-delay system, they are added and output as an estimated intake fuel amount. Note that the evaporation time constant and the fuel adhesion rate are calculated using the fuzzy neural network model described with reference to FIGS.

As described above, when the estimated intake air amount Ae and the estimated intake fuel amount Fe are calculated, the estimated air-fuel ratio is calculated by Ae / Fe in the estimated air-fuel ratio calculator 32 in FIG. The signal of the fuel ratio is calculated by the internal feedback calculation unit 3.
4 The signal of the estimated intake air amount is sent to the target air-fuel ratio calculation unit 33 and the intake fuel amount calculation unit 31 in FIG.
FIG. 7 is a block diagram showing a learning model of a target air-fuel ratio calculation unit 33 in FIG. The learning signal calculation unit 33c outputs the rotation fluctuation signal as a learning signal, and outputs the target air-fuel ratio learning unit 3c.
3d is used as teacher data for learning the target air-fuel ratio. The target air-fuel ratio learning unit 33d receives the engine speed, the estimated intake air amount calculated by the intake air amount calculation unit 30, and the estimated intake air amount change rate signal calculated by the change rate calculation unit 33a. Here, the target air-fuel ratio is calculated. Further, the target air-fuel ratio is corrected by a signal corrected by the engine temperature correction map 33e.

FIG. 12 shows the target air-fuel ratio learning section 33 of FIG.
FIG. 4D is a schematic configuration diagram of a fuzzy neural network for obtaining a target air-fuel ratio at d. The basic configuration and calculation method are the same as those of the fuzzy neural network for calculating the estimated intake air amount described with reference to FIGS.

After calculating the target air-fuel ratio from the engine speed and the estimated intake air amount, a correction coefficient is set from the estimated intake air amount change rate using an acceleration correction map, and the target air-fuel ratio is corrected using the correction coefficient. In this case, the rule shown in FIG. 8 is a two-dimensional map, and the three operating conditions A ₁₁ , which correspond to the engine speed and the estimated air intake amount, which are input information,
When A ₂₁ , A ₃₁ and A ₁₂ , A ₂₂ , A ₃₂ are used, the determination is performed by a combination of a total of six operating conditions and nine conclusions R ^{1 to} R ⁹ . The operating conditions A ₁₁ is the engine speed is "low speed region", A ₂₁ is "medium speed range", A ₃₁ is "high rpm", the operating conditions A ₁₂ is estimated intake air amount is "small", A
₂₂ indicates the condition with an ambiguous expression of “medium” and A ₃₂ indicates “many”, and the conclusions R ^{1 to} R ⁹ correspond to the magnitude of the engine speed and the magnitude of the estimated intake air amount. This shows the target air-fuel ratio. Based on these operating conditions and conclusions, the rule is, for example, "the target air-fuel ratio is 14.5 when the engine speed is in the middle speed range and the estimated intake air amount is medium." If the engine speed is in the high engine speed range and the estimated intake air amount is large, the target air-fuel ratio is 12. " The target air-fuel ratio learning section 33d is configured to be capable of learning, and in an initial state, a coupling coefficient wf (corresponding to the normalization fitness of the equation 3) such that the target air-fuel ratio becomes the stoichiometric air-fuel ratio in the entire region. ) Is corrected to perform learning in the fuzzy neural network, and thereafter, learning in the fuzzy neural network is performed by updating the coupling coefficient wf so as to reduce the learning signal, which is information on the deviation of the rotation fluctuation. .

FIG. 13 is a flowchart for learning the target air-fuel ratio of FIG. 12, which will be described with reference to FIG. FIG. 14 is a diagram showing the relationship between the rotation fluctuation of the crankshaft 3 and the air-fuel ratio. When the A / F rapidly fluctuates to the lean side and exceeds a predetermined value K, the rotation fluctuation of the engine (crankshaft 3) becomes predetermined. Exceeds the value R ₀ . Therefore, in this example,
While driving the engine as lean as possible,
When the rotation fluctuation exceeds R ₀ , the air-fuel ratio K is controlled to move to the rich side. That is, the rotation fluctuation of the crankshaft 3 is read in step S1, and it is determined in step S2 whether the rotation fluctuation is equal to or more than a predetermined value _R0 . If the rotation fluctuation is equal to or more than the predetermined value, the A / F is determined in step S3. The teacher data is changed so as to be on the rich side by the predetermined amount K ₀ , and the respective coefficients wc, wg, wf are updated. With this control, the air-fuel ratio moves to the rich side. It determines whether less than a predetermined value R _1, equal to or less than, by changing the teacher data as a / F becomes just lean predetermined amount K ₁ in step S5, to update the coupling coefficient wf .
With this control, the engine can be operated as lean as possible, and if the rotational fluctuation exceeds a predetermined value, the target air-fuel ratio can be changed to the rich side to suppress the rotational fluctuation and control the air-fuel ratio to an appropriate value. it can.

FIGS. 15 and 16 show an embodiment of the engine control device according to the present invention. FIG. 15 is a cross-sectional view showing the overall structure, and FIG. 16 is a cross-sectional view of a main part of FIG. In FIG. 15, the intake pipe 6 includes a throttle body 6a and an intake inlet pipe 6b, and the throttle body 6a is connected to an intake port 1a of the engine 1. Throttle body 6
a, a throttle valve 12 and an injector 13 are mounted, and a control box 50 is provided on an outer wall surface of the throttle body 6a.

In FIG. 16, an upright wall 51 and cylindrical walls 52 and 53 are integrally formed on a wall surface of the throttle body 6a, and a control box 50 for housing the control device 15 is formed. The cylindrical wall 53 is formed on the downstream side of the throttle valve 12, and has an intake pipe through hole 54 formed therein. The board 55 of the control device 15 is fixed to the standing wall 51 with screws 57 via vibration isolating rubber 56. A power supply circuit 15a, an input I / F 15b, a microcomputer 15d, and an output I / F 15e are provided on the substrate 54. An intake pipe negative pressure sensor (intake pressure detecting means) is provided on the lower surface of the substrate 55.
21, an intake pipe wall temperature detecting means 24 (temperature sensor 2) is provided, and an outside air temperature detecting means 23 (temperature sensor 1) for detecting the outside air temperature around the engine is provided on the upper surface of the substrate 54.

The intake pipe negative pressure sensor 21 is connected to the through hole 54.
, And is fixed to the periphery thereof by an elastic member 59 such as a rubber tube, and a filter is provided in the intake pipe through hole 54 as necessary. The intake pipe wall temperature detecting means 24 is housed in the cylindrical wall 52, and the periphery thereof is filled with a heat conductive resin 60. The control box 50 is filled with a mold resin 61 to ensure waterproofness and vibration resistance, and a cover member 62 is fixed to the standing wall 51. Here, 63 is a connector.

FIG. 17 is a sectional view showing the overall structure of another embodiment of the engine control device according to the present invention. In this embodiment, the throttle valve 12 is connected to the intake port 1 as much as possible.
The control box 50 is disposed on the lower surface of the throttle body 6a so as to be close to the a side, and the intake port 1a and the intake pipe negative pressure sensor 21 are connected by a detection pipe 64. In the present embodiment, since the intake pipe volume between the throttle valve 12 and the intake valve is reduced, the present invention can also be applied to an engine that reduces internal EGR generated when the intake and exhaust valves overlap.

Although the embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications can be made. For example, in the above embodiment, the present invention is applied to the learning model of the air-fuel ratio control. However, the present invention is not limited to this. By judging the state of the engine by the intake pressure detecting means and the intake pipe wall temperature detecting means. The present invention can be applied to all systems for controlling an engine, such as control of ignition timing and duty control of a fuel pump so as to minimize power consumption. In the above embodiment, an example in which the invention is applied to a four-cycle engine is shown.
It is also applicable to a two-stroke engine.

[0037]

As is apparent from the above description, according to the first and fifth aspects of the present invention, the number of signal lines between the detection means and the control box is reduced and the arrangement is simple. According to the second aspect of the present invention, it is possible to improve the vibration resistance of the intake pressure detecting means.
According to the invention described above, the invention can be applied to an engine that reduces the internal EGR generated when the intake and exhaust valves overlap, and according to the invention described in claim 4, the intake pipe wall temperature is accurately detected. According to the invention of claim 6, the vibration resistance of the substrate can be improved, and according to the invention of claim 7, the vibration resistance and waterproofness of the substrate can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an engine showing an example of a fuel injection control device to which the present invention is applied.

FIG. 2 is a configuration diagram of a control device 15 of FIG.

FIG. 3 is a block diagram showing a configuration of a control unit related to an injector performed in a microcomputer 15d of FIG. 2;

FIG. 4 is a block diagram illustrating a configuration of an intake pressure information processing unit 26 in FIG. 3;

5 (A) is a block diagram showing a configuration of a temperature information processing unit 35 in FIG. 3, and FIG. 5 (B) is a diagram for explaining calculation of an engine temperature.

FIG. 6 is a block diagram illustrating a configuration of a model base control unit 27 of FIG. 3;

7 shows a model of an intake air amount calculation unit 30 in FIG. 6,
FIG. 3 is a schematic configuration diagram of a fuzzy neural network for obtaining an estimated intake air amount.

FIG. 8 is a diagram showing the rules of FIG. 7 in the form of a map.

FIG. 9 is a diagram showing a correlation between an average intake pressure and a minimum intake pressure during one stroke and an intake air amount.

FIG. 10 is a block diagram showing a learning model of an intake fuel amount calculation unit 31 in FIG. 6;

11 is a block diagram illustrating a learning model of a target air-fuel ratio calculation unit 33 in FIG.

FIG. 12 shows a target air-fuel ratio learning unit 33d of FIG.
FIG. 2 is a schematic configuration diagram of a fuzzy neural network for obtaining a target air-fuel ratio.

FIG. 13 is a flowchart for learning a target air-fuel ratio of FIG. 12;

FIG. 14 is a diagram showing a relationship between a rotation fluctuation of a crankshaft and an air-fuel ratio.

FIG. 15 is a cross-sectional view showing one embodiment of an engine control device according to the present invention and showing an overall configuration.

FIG. 16 is a sectional view of a main part of FIG.

FIG. 17 is a cross-sectional view illustrating another embodiment of the engine control device according to the present invention, which illustrates an overall configuration thereof.

[Explanation of symbols]

 1a ... intake port 6 ... intake pipe 12 ... throttle valve 13 ... injector 21 ... intake pressure detecting means 24 ... intake pipe wall temperature detecting means 50 ... control box 55 ... substrate 56 ... anti-vibration rubber 59 ... elastic member 60 ... thermal conductivity Resin 61: Mold resin

Claims (7)

[Claims] 1. An injector and a throttle valve disposed in an intake pipe, a control box integrated with an intake pipe wall, a substrate fixed in the control box, and disposed on the substrate. An engine control device comprising: intake pressure detection means for detecting intake pressure downstream of a throttle valve; and intake pipe wall temperature detection means for detecting intake pipe wall temperature. 2. The engine control device according to claim 1, wherein an elastic member is mounted between said intake pressure detecting means and an intake pipe wall. 3. The engine control device according to claim 1, wherein said throttle valve is brought close to an engine intake port, and said intake port and said intake pressure detecting means are connected by a detection pipe. 4. The engine control according to claim 1, wherein said intake pipe wall temperature detecting means is provided on said intake pipe wall, and the periphery thereof is filled with a heat conductive resin. apparatus. 5. The engine control device according to claim 1, further comprising an outside air temperature detecting means disposed on said substrate for detecting an outside air temperature. 6. The control box according to claim 1, wherein said substrate is fixed to a control box via vibration-proof rubber.
The control device for an engine according to any one of the above. 7. The engine control device according to claim 1, wherein a mold resin is filled in the control box.