JPH0235863B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a throttle valve control device for a supercharged engine equipped with an exhaust turbo supercharger. This invention relates to a system in which throttle valve opening and supercharging pressure are electrically controlled to obtain predetermined output characteristics.

(Prior Art) Conventionally, as a technology for controlling the throttle valve opening in order to obtain a predetermined output performance with respect to the accelerator operation amount indicating the required engine output, as shown in Japanese Patent Application Laid-open No. 138235/1983, the accelerator an accelerator detection means for detecting the amount of operation; and a target opening degree calculation that receives the output of the accelerator detection means and calculates the target opening degree of the throttle valve in order to set the amount of air to be supplied to the engine as a target value according to the amount of accelerator operation. and a throttle valve drive means that receives the output of the target opening degree calculation means and drives the throttle valve to achieve the target opening degree, calculates the target throttle valve opening degree according to the accelerator operation amount, It is known that the opening degree of the throttle valve is controlled by feedback so that the opening degree is the same as that of the throttle valve. Then, by supplying the amount of fuel to the engine so that the air-fuel ratio is set in advance according to the intake air amount based on the throttle valve opening, the air-fuel ratio of the engine is set to the target value and a predetermined output characteristic is obtained. This is how it was done.

(Problem to be Solved by the Invention) By the way, the above-mentioned problem is solved for a supercharged engine that is equipped with an exhaust turbo supercharger in the intake passage and increases the filling efficiency of intake air by the supercharging pressure of the supercharger. When a conventional throttle valve control device is applied, the following problems occur. In other words, (i) Even if the throttle valve opening is controlled to match the target air amount according to the accelerator operation amount, the amount of intake air supplied to the engine increases and changes due to the supercharging pressure of the supercharger, and It becomes more than the output. For this reason, if the throttle valve opening is controlled by reducing the accelerator operation amount, the amount of air determined by the throttle valve opening will decrease, and the intake air amount due to supercharging will decrease due to the decrease in the supercharging effect. As a result, the amount of intake air supplied to the engine decreases significantly, and as a result, the output suddenly decreases, making it difficult to obtain an output characteristic that is linear with respect to the amount of accelerator operation.

(ii) Also, when the boost pressure from the turbocharger is acting, controlling the opening of the throttle valve to reduce its opening will reduce the supercharging effect and cause a loss in supercharging of the turbocharger. will be invited.

Therefore, the present invention focuses on the fact that the supercharging effect by the exhaust turbo supercharger does not work in the low speed range, but works in the high speed range where the throttle valve is opened above a predetermined opening degree. When the accelerator operation amount is smaller than a predetermined value at which the supercharging effect of the supercharger starts to work, the throttle valve opening is controlled to the target air amount, and the accelerator operation amount causes the supercharging action of the supercharger to start working. When it is larger than a predetermined value, the throttle valve is fully opened and the supercharging pressure of the supercharger is controlled to match the target air amount, thereby eliminating supercharging loss of the supercharger in a supercharged engine. The purpose is to obtain smooth and linear output characteristics without torque shock with respect to the amount of accelerator operation.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an accelerator detection means for detecting an accelerator operation amount in an engine equipped with an exhaust turbo supercharger, as shown in FIG. 22, and receives the output of the accelerator detection means 22, and when the accelerator operation amount is smaller than a predetermined value at which the supercharging action of the supercharger starts to work, the amount of air supplied to the engine according to the accelerator operation amount. The target opening calculation means 41 calculates the target opening of the throttle valve to make the target value, and the output of the accelerator detection means 22 is received, and the accelerator operation amount is set to a predetermined value at which the supercharging action of the supercharger starts to work. A target supercharging pressure calculating means 46 is provided for calculating a target value of the supercharging pressure by the supercharger in order to set the amount of air supplied to the engine to the target value in accordance with the accelerator operation amount. Throttle valve driving means 42 receives the output of the target opening calculation means 41 and drives the throttle valve to achieve the target opening.
and receiving the output of the target boost pressure calculation means 46,
A supercharging pressure control means 47 is provided to control the supercharging pressure to a target value. Furthermore, in response to the output of the accelerator detection means, when the accelerator operation amount is equal to or greater than a predetermined value at which the supercharging action of the supercharger is activated, a full open signal is generated that sends a signal to the throttle valve driving means 42 to fully open the throttle valve. The structure is such that a means 44 is provided.

(Function) With the above configuration, in the present invention, when the accelerator operation amount is below a predetermined value at which the supercharging action of the exhaust turbo supercharger does not actually work, the target opening degree of the throttle valve is determined according to this accelerator operation amount. The opening degree of the throttle valve is controlled so as to reach this target opening degree, and the target air amount is supplied to the engine. on the other hand,
When the amount of accelerator operation is equal to or higher than a predetermined value at which the supercharging action of the supercharger actually operates, the throttle valve is fully opened, and a target value of supercharging pressure is determined according to the amount of accelerator operation, and this target value is reached. The boost pressure is controlled in this way, and the target amount of air is supplied to the engine.

As a result, the throttle valve opening degree and the boost pressure control are not performed in parallel, but are performed separately after the predetermined accelerator operation amount at which the supercharging action of the supercharger starts to work, so that each control is As a result, the target air amount is supplied to the engine with high precision, and the connection between the two controls is performed smoothly, resulting in smooth output characteristics that are linear with respect to the amount of accelerator operation, that is, smooth without torque shock. Furthermore, since the throttle valve is fully open during supercharging pressure control, there is no reduction in supercharging effect due to the throttle valve, and supercharging loss of the supercharger is prevented.

(Example) Hereinafter, an example of the present invention will be described based on the drawings from FIG. 2 onwards.

FIG. 2 shows the overall configuration of a throttle valve control device for a supercharged engine according to an embodiment of the present invention. In FIG. 2, 1 is, for example, a 4-cylinder engine, 2
4 is an intake passage whose one end opens to the atmosphere via the air cleaner 3 and the other end opens to the engine 1 to supply intake air (air) to the engine 1;
This is an exhaust passage that opens at one end and opens at the other end to the atmosphere to discharge exhaust gas from the engine 1. Reference numeral 5 denotes an accelerator pedal that is depressed in response to an engine output request, and 6 a throttle valve that is disposed in the intake passage 2 and controls the amount of intake air.
has no mechanical relationship with the accelerator pedal 5, and is electrically controlled by the amount of depression of the accelerator pedal 5, that is, the amount of accelerator operation, as will be described later. 7
is a throttle actuator consisting of a step motor or the like that opens and closes the throttle valve 6.
Reference numeral 8 denotes a catalyst device which is interposed in the exhaust passage 4 and purifies exhaust gas. Reference numeral 9 denotes an exhaust turbo supercharger disposed across the upstream side of the catalyst device 8 in the exhaust passage 4 and the upstream side of the throttle valve 6 in the intake passage 2, and is driven by the exhaust flow flowing through the exhaust passage 4. This supercharges the engine 1 with intake air from the intake passage 2. 10 is a supercharger 9 having an intake passage 2 at one end.
Downstream, the other end is a relief passage that opens upstream of the supercharger 9 in the intake passage 2 and relieves a part of the supercharged intake air from the supercharger 9 to the intake passage 2 upstream of the supercharger 9. be. A supercharging pressure control actuator 11 consisting of a relief valve that controls opening and closing of the relief passage 10 is interposed in the middle of the relief passage 10, and the supercharging pressure control actuator 11 controls the supercharging pressure from the supercharger 9. I try to control it.

Furthermore, 12 is a supercharger 9 having an exhaust passage 4 at one end.
A throttle valve 6 that opens upstream and has an intake passage 2 at the other end.
An exhaust gas recirculation passage 13 opens downstream and recirculates part of the exhaust gas from the exhaust passage 4 to the intake passage 2, and an intake negative pressure 13 is provided in the middle of the exhaust gas recirculation passage 12 to control the amount of exhaust gas recirculation. A reflux control valve 14 is a diaphragm device whose operating source is the reflux control valve 1.
3 is a solenoid valve that controls opening and closing.

On the other hand, reference numeral 15 denotes a fuel injection valve disposed downstream of the throttle valve 6 in the intake passage 2 to inject and supply fuel. The fuel tank 19 is connected to the fuel tank 19 through the fuel tank 19, and fuel is supplied from the fuel tank 19, and the surplus fuel is returned to the fuel tank 19 through a return passage 21 with a fuel pressure regulator 20 interposed therebetween. Therefore, fuel at a predetermined pressure is supplied to the fuel injection valve 15.

In addition, 22 is an accelerator pedal position sensor serving as an accelerator detection means for detecting the amount of depression of the accelerator pedal 5, that is, the amount of accelerator operation α;
23 is an air flow meter that is arranged upstream of the throttle valve 6 in the intake passage 2 and detects the intake air amount Qa _R ;
24 is an intake temperature sensor which is also arranged upstream of the throttle valve 6 in the intake passage 2 and detects the intake air temperature;
25 is a pressure sensor that detects the intake pressure (supercharging pressure) P _B downstream of the supercharger 9 in the intake passage 2, 26 is a throttle position sensor that detects the opening degree of the throttle valve 6, and 27 is a sensor for detecting engine cooling water. A water temperature sensor that detects the temperature T _W ; 28 is a catalyst device 8 in the exhaust passage 4;
An O ₂ sensor 29 that is arranged upstream and detects the air-fuel ratio λ of the engine 1 from the oxygen concentration component in the exhaust gas.
A recirculation sensor is attached to the recirculation control valve 13 and detects when the exhaust gas is recirculated. These detection signals 22 to 29 are input to a control unit 30 consisting of an analog computer, etc., and the control unit 30 controls the throttle actuator 7, boost pressure control actuator 11, solenoid valve 14, and fuel injection valve 15. is controlled. Further, an igniter 31 is connected as an input to the control unit 30, and receives a signal indicating the number of ignitions, that is, the engine rotational speed Ne.
Further, a duplexer 32 and a battery 33 are connected as inputs to the control unit 30, and receive signals of ignition timing and battery voltage _VB , respectively.

Next, the operation of the control unit 30 will be explained with reference to FIG. Note that FIG. 3 shows the case of a four-cylinder engine.

In Fig. 3, first, to describe the throttle valve opening control system, M _A1 is set to a target value Qa ₁ of air supplied to the engine 1 so that the air-fuel ratio is set in advance for the accelerator operation amount α. This first map is configured to receive the output from the accelerator pedal position sensor 22 and set the target air amount Qa ₁ to be supplied to the engine 1 according to the accelerator operation amount α. M _A2 is a second map in which the minimum air amount Qam is set to provide the air-fuel ratio necessary for idling up with respect to the engine cooling water temperature T _W. The minimum air amount Qam for water temperature correction is set according to the water temperature _TW . 34 receives each output of the first map M _A1 and the second map M _A2 , and calculates the target air amount Qa ₁ obtained from the first map M _A1 and the minimum air for water temperature correction obtained from the second map M _A2 . This is a maximum value selection circuit that selects the maximum value Qa ₂ from the quantity Qam, and when the target air quantity Qa ₁ is lower than the minimum air quantity Qam for water temperature correction, the minimum air quantity Qam for water temperature correction is selected due to idle up. This ensures good engine drivability. Moreover, M _A3 is a third map in which the maximum air amount Qa _M determined by the engine speed Ne is set with respect to the engine speed Ne, and it receives the output from the igniter 31 and corresponds to the engine speed Ne. The maximum air amount Qa _M is set. 35 is the maximum value selection circuit 3
4 and the third map M _A3 , the maximum air amount Qa ₂ obtained by the maximum value selection circuit 34 and the third map M
This is a minimum value selection circuit that selects the maximum value Qa ₃ from the maximum air amount Qa _M determined by map M _A3 , so that the target air amount Qa ₁ is the engine rotation speed.
When the maximum air amount Qa _M determined by Ne is exceeded, it is meaningless to set the target amount to be more than the amount of air that can be taken in when the throttle valve 6 is fully open.
By selecting the maximum air amount Qa _M and limiting the maximum value, a fully open signal corresponding to fully opening the throttle valve 6 is supplied to the throttle valve driving means 43, which will be described later. As described above, the target air amount Qa ₃ is determined for the accelerator operation amount α, taking into account the correction for the engine coolant temperature T _W and the correction for the maximum air amount when the throttle valve 6 is fully open, which is determined by the engine speed Ne.

Furthermore, 36 is a divider which receives the output from the minimum value selection circuit 35 and divides the target air amount Qa ₃ by the value obtained by doubling the engine speed Ne (Ne x 2). Intake amount per cylinder
I'm looking for Ac ₁ . M _A4 is a fourth map in which the throttle valve opening θ ₁ that should be the target intake air amount Ac ₁ for the engine number Ne is set, and the divider 36
The throttle valve opening degree θ ₁ that should be the target intake air amount Ac ₁ is set based on the output from the engine. Reference numeral 37 denotes an intake air amount feedback correction module, which receives the signal of the target intake air amount Ac ₁ from the divider 36 and also receives the signals of the actual air amount Qa _R and the engine speed Ne measured by the air flow meter 24. , the actual intake air amount Ac _R per cylinder calculated from the actual air amount Qa _R and the engine number Ne
(=Qa _R /(Ne×2)) and the target intake air amount Ac ₁ to calculate a feedback correction coefficient Ca _FB for feedback correcting the throttle valve opening according to the deviation. Furthermore, M _A5 is
A fifth map for determining whether the target intake air amount Ac ₁ (that is, the accelerator operation amount α) is larger than a predetermined value at which the supercharging action of the supercharger 9 starts to operate, and the output from the divider 36 target intake air volume Ac ₁
When (accelerator operation amount α) is below a predetermined value at which the supercharging action of the supercharger 9 does not work, the L signal is output, and when it is above the predetermined value at which the supercharging action of the supercharger 9 does not work, the H signal is output.
The signals are transferred to the first and second changeover switches 3, respectively.
8 and 39, and when the L signal is output, both switches 38 and 39 are switched to the L terminal side, and the H signal is output.
At the time of signal output, both changeover switches 38 and 39 are respectively switched to the H terminal side. 4
0 receives the output from the fourth map M _A4 and also receives the intake air amount feedback correction module 37.
When the L signal from the fifth map M _A5 is output, the target throttle valve opening θ ₁ obtained from the fourth map M _A4 is applied to the intake air amount feedback correction module. 37
This is a multiplier that performs multiplication correction using the feedback correction coefficients Ca _{and FB} determined by and outputs the target opening degree θ ₂ . As described above, when the accelerator operation amount α is below a predetermined value at which the supercharging action of the supercharger 9 does not actually work, the throttle valve is adjusted so that the amount of air supplied to the engine 1 is set to the target value Ac ₁ according to the accelerator operation amount α. 6 target opening θ ₂
It constitutes a target opening degree calculation means 41 that calculates. Then, the signal of the target throttle valve opening θ ₂ corrected by the multiplier 40 is transmitted to the throttle actuator 7 via the L terminal of the second changeover switch 39.
Therefore, when the accelerator operation amount α is less than a predetermined value, the output of the target opening calculation means 41 is received;
A throttle valve driving means 42 is configured to drive and control the throttle valve 6 so that the throttle valve opening degree θ ₂ becomes the target throttle valve opening degree.

On the other hand, 43 is a full-open signal generator that generates a full-open signal corresponding to the full opening of the throttle valve 6.
It is connected to the throttle actuator 7 via a terminal, and when the fifth map M _A5 outputs an H signal, that is, when the accelerator operation amount α is equal to or higher than a predetermined value at which the supercharging action of the supercharger 9 actually operates. A fully open signal is supplied to the throttle valve driving means 42 to open the throttle valve 6.
A fully open signal generating means 44 is configured to fully open the opening.

In addition, M _A6 sets the target value P of the boost pressure for the target intake air amount Ac 1 so that the amount of air supplied to the engine 1 according to the accelerator operation amount α becomes the target value when the accelerator operation amount α is greater than _or equal to a predetermined value. _B is the sixth map set, which receives a signal of the target intake air amount Ac ₁ and sets the target supercharging pressure P _B in accordance with the target intake air amount Ac ₁ . 45 receives the output from the sixth map M _A6 and receives the output from the intake air amount feedback correction module 37 via the H terminal of the first changeover switch 38, and when the H signal is output from the fifth map M _A5 . Target boost pressure determined by 6th map M _A6
P _B to intake air volume feedback correction module 37
This is a multiplier that performs multiplication correction using the feedback correction coefficient Ca _FB determined by . As described above, when the accelerator operation amount α is equal to or greater than a predetermined value at which the supercharging action of the supercharger 9 actually operates, the supercharger is activated so that the amount of air supplied to the engine 1 is set to the target value according to the accelerator operation amount α. 9 constitutes a target supercharging pressure calculating means 46 for calculating the target value P _B of the supercharging pressure. The signal of the target boost pressure P _B corrected by the multiplier 45 is output to the boost pressure control actuator 11, and therefore, when the accelerator operation amount α exceeds a predetermined value, the signal of the target boost pressure P B corrected by the multiplier 45 is outputted to the boost pressure control actuator 11. A supercharging pressure control means 47 receives the output and controls the supercharging pressure to a target value.

Next, referring to the fuel supply amount control system in FIG. 3, M _B7 is set to a target value Qf ₁ of fuel to be supplied to the engine 1 so that the air-fuel ratio is set in advance for the accelerator operation amount α. The seventh map receives the output from the accelerator pedal position sensor 22 and sets a target fuel amount Qf ₁ to be supplied to the engine 1 according to the accelerator operation amount α.
M _B8 is the air volume set in the second map M _A2 above.
This is the eighth map in which the minimum fuel amount Qfm is set for the engine coolant temperature T _W so that the air-fuel ratio necessary for idle up is obtained for Qam. Minimum fuel amount Qfm for water temperature correction according to temperature T _W
Set. 50 receives each output of the seventh map M _B7 and the eighth map M _B8 , and outputs the seventh map M _B7.
This is a maximum value selection circuit that selects the maximum value Qf ₂ of the target fuel amount Qf ₁ obtained in 1 and the minimum fuel amount Qfm for water temperature correction obtained in the 8th map M _B8 , and the above target fuel amount Qf ₁ is the minimum fuel amount for water temperature correction
When it is below Qfm, the minimum fuel amount Qfm for water temperature correction is selected to ensure good engine drivability due to the idle increase. Also,
M _B9 is the maximum fuel amount for the engine speed Ne so that the preset target air-fuel ratio is achieved for the maximum air amount Qa _M set in the third map M _A3 above.
This is the ninth map in which Qf _M is set, and the maximum fuel amount Qf _M is set according to the engine speed Ne.
51 receives each output of the maximum value selection circuit 50 and the ninth map M _B9 , and selects the maximum fuel amount Qf ₂ determined by the maximum value selection circuit 50 and the maximum fuel amount Qf _M determined by the ninth map M _B9 . This is a minimum value selection circuit that selects the minimum value Qf ₃ of the above target fuel amount.
Qf ₁ is the maximum fuel amount determined by engine speed Ne
When the amount of air exceeds Qf _M , that is, when the target air amount Qa ₁ exceeds the maximum air amount Qa _M determined by the engine speed Ne as described above, the throttle valve 6 is fully open and the amount of air exceeds the amount that can be taken in. When the target value is set, the maximum air amount Qa _M is selected and the maximum fuel amount Qf _M is selected so that the target air-fuel ratio is set in advance for the intake air amount supplied to the engine 1. As described above, as in the case of the air amount, the target fuel is calculated based on the accelerator operation amount α, taking into account the correction for the engine cooling water temperature T _W and the correction for the maximum fuel amount when the throttle valve 6 is fully open, which is determined by the engine speed Ne. The quantity Qf ₃ is found.

Then, the target fuel amount Qf ₃ signal from the maximum value selection circuit 51 is applied to the fuel injection via the divider 52, the first to third multipliers 53 to 55, the fuel cut switch 56, and the fuel injection valve correction circuit 57. valve 15
is output to. The divider 52 receives the output from the minimum value selection circuit 51 and divides the target fuel amount Qf ₃ into 2
Assuming that fuel is injected into each cylinder at the same time, calculate the amount of fuel supplied per cylinder by dividing by the engine speed Ne.
This is to calculate Qfi. Further, the first multiplier 53 converts the target fuel supply amount Qfi obtained by the divider 52 into a water temperature correction coefficient C _TW and an enrichment correction module 58 for the engine cooling water temperature T _W obtained from the tenth map M _B10 . Multiply and correct the enrichment correction coefficient C ER obtained by _ER to obtain the target fuel supply amount.
This is to calculate Qfi ₁ . This enrichment correction module 58 determines the engine frequency based on a zone signal from a zone determination module 62, which will be described later.
When the intake air amount Ac ₁ with respect to Ne is in the enrichment line region, an enrichment correction coefficient C _ER (for example, 1.08) is output in order to uniformly increase the fuel supply amount by, for example, 8%.

Further, the second multiplier 54 is connected to the first multiplier 5
The target fuel supply amount Qfi ₁ obtained in step 3 is calculated using the learning correction coefficient obtained by the fuel learning correction module 59.
The target fuel supply amount Qfi ₂ is calculated by performing multiplication correction using C _STD . This fuel learning correction module 59
is based on the zone signal from the zone determination module 62 and the fuel feedback correction coefficient _CfFB signal from the fuel feedback correction module 60, which will be described later. When, the fuel learning correction coefficient
After setting C _STD to its initial value = 1.0, use the following formula C _STD = C _STD + 1/8 (Peak value of Cf _FB of the past 8 times + Bottom value of Cf _FB of the past 8 times) / 16 - 1.0} The data is sequentially updated and output.

Further, the third multiplier 55 is a component of the second multiplier 54
The target fuel supply amount Qfi ₂ obtained in the above is multiplied and corrected by the fuel feedback correction coefficient _CfFB obtained by the fuel feedback correction module 60 to calculate the target fuel supply amount Qfi ₃ . The fuel feedback correction module 60 operates based on the zone signal from the zone determination module 62 and the air-fuel ratio λ signal from the O ₂ sensor 28 under the following conditions, for example: Engine cooling water temperature T _W >60°C Intake air amount Ac ₁ ≧Cylinder stroke volume 10% of the intake air amount Ac ₁ relative to the engine speed Ne is outside the enrichment line and fuel cut zone. When the _O2 sensor 28 is active, the fuel feedback correction coefficient is set to feedback control the fuel supply amount. Cf _FB (e.g.
0.8≦Cf _FB ≦1.25, proportional constant P=0.06, integral constant I=0.05/sec).

Furthermore, the fuel cutter switch 56 is
The opening/closing is controlled by the output signal from the fuel cut control module 61. This fuel cut control module 61 receives the zone signal from the zone determination module 62 and the target intake amount.
Based on the Ac ₁ signal, for example, when the following conditions are met: engine cooling water temperature T _W > 6°C, intake air amount Ac ₁ < 10% of cylinder stroke volume, engine speed Ne > 1000 rpm, the fuel cut is turned off to cut fuel injection. It controls the switch 56 to open. Here, the zone determination module 62
creates condition determination signals (zone signals) for each of the control modules 58 to 61 based on the engine frequency Ne, target intake air amount Ac ₁ , engine coolant temperature _TW , and air-fuel ratio λ.

Furthermore, the fuel injection valve correction circuit 57
Upon receiving the target fuel supply amount Qfi ₃ signal from the third multiplier 55 and the battery voltage V _B signal from the battery 33, a pulse signal is sent as a target fuel supply amount signal to the fuel injection valve 15 according to the battery voltage V _B. is corrected and output to the fuel injection valve 15. As described above, the fuel injection valve 15 is driven for a predetermined period of time in synchronization with ignition, and the fuel supply amount is controlled to the target value.

Therefore, in the embodiment described above, when the accelerator operation amount α is below a predetermined value at which the supercharging action of the supercharger 9 does not actually operate, the target opening calculation means 41 supplies the gas to the engine 1 according to the accelerator operation amount α. A target opening degree of the throttle valve 6 is determined to set the air amount to a target value, and the throttle valve driving means 42 operates the throttle valve 6 based on the determined target opening degree.
The opening degree is controlled so that it reaches the target value. on the other hand,
Accelerator operation amount α at which the supercharging action of the supercharger 9 actually operates
is greater than a predetermined value, the full open signal generating means 44
As a result, the throttle valve 6 is fully opened, and the target boost pressure calculation means 46 determines the target value of the boost pressure by the supercharger 9 so that the amount of air to be supplied to the engine 1 is set to the target value, and the target value is set to the target value. Based on this, the supercharging pressure control means 47 controls the supercharging pressure to reach the target value. As a result, after the predetermined accelerator operation amount at which the supercharging action of the supercharger 9 begins to operate, the opening degree control of the throttle valve 6 and the supercharging pressure control are performed separately to obtain the target intake air amount. So,
It is possible to accurately supply the target intake air amount to the engine in response to the accelerator operation amount α that indicates the required engine output, and the connection between the above two controls is performed smoothly, so that the accelerator operation amount α is linear. It is possible to obtain smooth output characteristics without torque shock. Furthermore, during the above-mentioned supercharging pressure control, the throttle valve 6 is fully opened by the fully open signal generating means 44, so that the supercharging effect of the throttle valve 6 is not reduced, and the supercharger 9 is Supply loss can be prevented.

In addition, a target air amount and a target fuel amount are respectively determined for the accelerator operation amount α, and based on the determined target values, the intake air amount and fuel supply amount are set to the target values simultaneously and in parallel. As a result, the intake air amount and fuel supply amount both change to the target value at the same time without any time lag in response to changes in the accelerator operation amount α, so even during transient operation of the engine, the amount of fuel is The air-fuel ratio of the engine can be accurately controlled to the target air-fuel ratio without causing a response delay, and thus the acceleration performance and driving performance of the engine can be improved. Moreover, since the intake air amount and fuel supply amount are simultaneously controlled to a preset air-fuel ratio in response to the accelerator operation amount α, it is possible to precisely control the target air-fuel ratio without requiring feedback control. Therefore, control can be simplified.

(Effects of the Invention) As explained above, according to the present invention, in an engine equipped with an exhaust turbo supercharger, when the accelerator operation amount is less than a predetermined value at which the supercharging action of the supercharger does not work, the throttle valve opening is controlled. When the amount of accelerator operation exceeds a predetermined value at which the supercharging action of the supercharger is activated, the amount of intake air supplied to the engine is adjusted to the target value according to the amount of accelerator operation by controlling the supercharging pressure with the throttle valve fully open. As a result, it is possible to accurately control the intake air amount in relation to the accelerator operation amount while preventing supercharging loss in the supercharger, and to make the transition between the above two types of control smooth. This makes it possible to obtain smooth and linear output characteristics with no torque shock relative to the amount of accelerator operation.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 and 3 show an embodiment of the present invention, with FIG. 2 being a general schematic diagram and FIG. 3 being a block diagram showing the operational flow of the control unit. 1...engine, 5...accelerator pedal, 6...
... Throttle valve, 7 ... Throttle actuator, 9 ... Supercharger, 11 ... Boost pressure control actuator, 22 ... Accelerator pedal position sensor, 30 ... Control unit, 41 ... Target opening degree Calculating means, 42...Throttle valve driving means, 44...Full open signal generating means, 46...Target supercharging pressure calculating means, 47...Supercharging pressure controlling means.

Claims (1)

[Claims] 1. In a supercharged engine equipped with an exhaust turbo supercharger, there is an accelerator detection means for detecting an accelerator operation amount, and an output of the accelerator detection means is received, and the accelerator operation amount indicates that the supercharging action of the supercharger is actually activated. a target opening calculation means for calculating a target opening of the throttle valve in order to set the amount of air supplied to the engine as a target value in accordance with the accelerator operation amount, and an output of the accelerator detection means; When the amount of accelerator operation is larger than a predetermined value at which the supercharging action of the supercharger starts to work, the amount of air supplied to the engine is set to a target value according to the amount of accelerator operation by the supercharger. a target supercharging pressure calculating means for calculating a target value of the supercharging pressure; a throttle valve driving means for receiving the output of the target opening calculating means and driving the throttle valve to achieve the target opening; and the target supercharging pressure. A supercharging pressure control means that receives the output of the calculation means and controls the supercharging pressure to a target value, and receives the output of the accelerator detection means and sets the accelerator operation amount to a predetermined value at which the supercharging action of the supercharger actually operates. A throttle valve control device for a supercharged engine, characterized in that the throttle valve drive means is provided with full-open signal generating means for generating a signal to fully open the throttle valve in the above case.