JPH0861135A - Intake air quantity control device for engine - Google Patents

Abstract

PURPOSE: To accurately detect the intake air quantity in response to change in flow delay of the intake air or change in the intake air pulse. CONSTITUTION: In an intake air passage 10, an air flow meter 11 and a supercharger type supercharger 13 as a variable member are arranged. Rotation ratio of the supercharger 13 to a crankshaft 31 is switched between the low speed rotation ratio for switching to the low supercharging condition and the high speed rotation ratio for switching to the high supercharging condition, and the stop condition of the supercharger 13 can be selected. In response to the stop condition, low supercharging condition and high supercharging condition of the supercharger 13, degree of annealing of the output of the air flow meter 11 and the correction coefficient of pulse are changed. Degree of annealing and the correction coefficient of pulse can be changed in response to the degree of intensity of the pressure of the downstream of the supercharger 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine intake air amount control device.

[0002]

2. Description of the Related Art In order to detect the amount of intake air supplied to the cylinder of an engine, intake air amount detecting means is provided in the intake passage of the engine. Since the intake passage between the intake air amount detecting means and the cylinder has a considerable capacity, the intake air amount detected by the intake air amount detecting means during a transition such as acceleration / deceleration due to a flow delay of intake air. There is a difference between the amount of intake air actually sucked into the cylinder. Therefore, JP-A-4-41945
As shown in the publication, the intake air amount signal from the intake air amount detecting means is smoothed by using a predetermined smoothing coefficient in consideration of the flow delay of intake air.

On the other hand, the pulsation of the intake air occurs due to the opening and closing of the intake port caused by the rotation of the engine, and this pulsation causes an error when the intake air amount is detected. Therefore, the intake air amount signal after the smoothing process is also corrected with a correction coefficient for correcting the pulsation of intake air. The smoothing coefficient for the smoothing process and the correction coefficient for pulsation correction are set to one type in consideration of the intake passage structure.

[0004]

By the way, in recent engines, the structure of the intake passage tends to be complicated, and in some cases, the variable structure is used to change the flow delay of intake air or change the pulsation of intake air. In this case, the intake air amount cannot be accurately detected in the intake passage structure having the variable structure by setting only one type of the smoothing coefficient and the pulsation correction coefficient. For example, a supercharger that is mechanically driven by the engine is arranged in the intake passage, and the supercharger is placed in, for example, a stopped state (non-supercharging state) and a driving state (supercharging state). When switching between
The flow delay of intake air differs between the stopped state and the driving state, and the pulsation generation state of intake air also differs.

The present invention has been made in consideration of the above circumstances. Even if a variable member that influences the detection of the intake air amount is provided in the intake passage, the intake air amount can be accurately controlled. An object of the present invention is to provide an intake air amount control device for an engine, which can be detected well.

[0006]

In order to achieve the above-mentioned object, the present invention has a construction as specifically described in the claims (independent claim 1,
2, 3, 13, 16). That is, the structure of the present invention will be briefly described based on its basic idea. The operating state of the variable member that affects the intake air amount detection (for example, the operation of the supercharger mechanically driven by the engine). The degree of smoothing (the smoothing coefficient) and the degree of correction of the pulsation correction (correction coefficient) are changed according to the state. Further, in the present invention, the ease of intake of the intake air into the cylinder corresponds to the pressure of the intake passage downstream of the variable member when comprehensively taken into consideration. Therefore, the degree of smoothing depends on this pressure. I am changing it.

[0007]

According to the invention described in claim 1, since the degree of smoothing is changed according to the operating state of the variable member, which greatly affects the flow delay of the intake air, the intake air amount is accurately detected. be able to.

According to the second aspect of the present invention, the degree of smoothing is changed according to the intake passage pressure downstream of the variable member, which greatly affects the flow delay of the intake air, so that the intake air amount is accurately detected. be able to.

According to the third aspect of the present invention, since the degree of smoothing is changed according to the operating state of the supercharger, which has a great influence on the flow delay of intake air, the intake air amount can be detected accurately. You can

With the configuration as described in claim 4, it is possible to accurately detect the intake air amount by changing the degree of moderation depending on the stopped state and the supercharged state of the supercharger. With the configuration as described in claim 5, it is possible to accurately detect the intake air amount by changing the degree of moderation depending on the low supercharging state and the high supercharging state of the supercharger.

With the structure as described in claim 6, the supercharger is used as a supercharger mechanically driven by the engine, and the supercharger is in a low supercharging state and a high supercharging state. Switching between the supply state and the engine, supercharger
This can be done by changing the rotation ratio with the jar.

With the configuration as described in claim 7, when the output, that is, the torque is required, at the time of a high load, a high rotation ratio, that is, a high supercharging state is set, and it is unnecessarily high supercharging state in response to the above demand. It is also preferable from the viewpoint of improving fuel efficiency.

With the structure as described in claim 8, the moderation degree is set in consideration of the fact that the intake flow delay becomes smaller in the high supercharging state than in the low supercharging state. The intake air amount can be detected with high accuracy.

With the structure as described in claim 9, the moderation degree is changed in consideration of the fact that the opening degree of the opening degree adjusting means, that is, the opening degree of the bypass passage affects the flow delay of the intake air. Therefore, the intake air amount can be accurately detected.

With the structure of the tenth aspect, by adjusting the opening degree of the bypass passage by adjusting the opening degree, it is possible to prevent a large torque change due to the change of the operating state of the supercharger, while the intake is performed. The amount of air can be detected accurately.

According to the eleventh aspect, it is possible to accurately detect the intake air amount by changing the grading degree according to the flow delay of the intake air.

According to the twelfth aspect, the moderation degree is appropriately set according to the magnitude of the pressure that affects the flow delay of the intake air, and the intake air amount is accurately detected. be able to.

According to the thirteenth aspect of the present invention, the intake air amount can be accurately detected by changing the correction degree of the pulsation correction according to the operating state of the variable member that affects the pulsation of the intake air. You can

According to the structure described in claim 14, the correction degree is changed according to the operating state of the supercharger, which has a great influence on the pulsation of the intake air, and the intake air amount is accurately measured. Can be detected.

With the structure as described in claim 15, pulsation correction is appropriately performed according to the supercharger stopped state, the low supercharging state and the high supercharging state, and the intake air amount. Can be accurately detected.

According to the sixteenth aspect of the present invention, the smoothing process and the pulsation correction are appropriately performed according to the operating state of the supercharger, which greatly affects the flow lag of the intake air and the pulsation state. Thus, the intake air amount can be detected extremely accurately.

According to the seventeenth aspect of the invention, the smoothing process and the pulsation correction are appropriately performed according to the stop state, the low supercharging state and the high supercharging state of the supercharger. The amount of intake air can be detected extremely accurately.

With the structure as described in claim 18, the intake air amount is detected more accurately by performing the smoothing process in consideration of the opening degree of the bypass passage which affects the flow delay of the intake air. can do.

By adopting the structure as described in claim 19, while preventing a rapid change of the torque,
An effect corresponding to 8 can be obtained.

[0025]

Embodiments of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, E is an engine, and an intake port 2 and an exhaust port 3 are opened in a combustion chamber (cylinder) 1 of the engine, the intake port 2 is opened and closed by an intake valve 4, and an exhaust port is provided. The exhaust valve 3 is opened and closed. The engine 1 is a spark ignition type engine that is ignited by a spark plug 6. In the exhaust passage 7 connected to the exhaust port 3,
An air-fuel ratio sensor (O ₂ sensor) 8 and an exhaust gas purification catalyst (three-way catalyst) 9 are provided.

In the intake passage 10 connected to the intake port 4,
From the upstream side to the downstream side, an air flow meter 11 serving as an intake air amount detecting means, a throttle valve 12 linked with an accelerator, a rheism type supercharger 13 serving as a variable member, and an intercooler. 14, a fuel injection valve 15 is provided, and a pressure sensor 16 and an intake temperature sensor 17 are provided in the intake passage 10 between the intercooler 14 and the fuel injection valve 15. In the embodiment, the air flow meter 11 is of a volume flow rate measuring type such as a flap type or a hot wire type.

The intake passage 10 includes a supercharger 13
A bypass passage 20 for bypassing is connected. The upstream end of the bypass passage 20 is connected to the intake passage 10 between the throttle valve 12 and the supercharger 13, and the downstream end of the bypass passage 20 is connected to the supercharger 13 and the intercharger. 14 is connected to the intake passage 10. A duty solenoid type ABV (opening degree adjusting valve) 21 for constituting an opening degree adjusting means is connected to the bypass passage 20.

The supercharger 13 is mechanically driven by the engine E. The drive system path of this supercharger 13 is constructed as follows. That is, reference numeral 31 is a crankshaft of the engine E, 32 is an oil pump shaft, and both shafts 31 and 32 are always linked by a belt 33 at a predetermined constant rotation ratio. A pulley 34 with an electromagnetic clutch is attached to the crankshaft 31, and a pulley 35 with an electromagnetic clutch is attached to the pump shaft 32. The diameter of the pulley 34 is larger than that of the pulley 35.
Is larger than the diameter. A pulley 36 is fixed to the input shaft (rotating shaft) 13a of the supercharger 13, and a belt 37 is wound around the pulley 36 and the pulleys 34 and 35. The input shaft 1
A rotational speed sensor for detecting the rotational speed of 3a is designated by reference numeral 18.

Now, when the electromagnetic clutches of the crankshaft pulley 34 and the pump shaft pulley 35 are both disengaged, the rotation of both pulleys 34, 35 is stopped, and the supercharger 13 is stopped. Stopped (non-supercharged state). When the electromagnetic clutch of the crankshaft pulley 34 is disengaged and the electromagnetic clutch of the pump shaft pulley 35 is connected, the crankshaft 31 is rotated by the belt 33,
It is transmitted to the input shaft 13a of the supercharger 13 via the pump shaft 32, the small-diameter pulley 35 for the pump shaft, and the belt 37, and the input shaft 1 to the crank shaft 31 at this time is transmitted.
The rotation ratio of 3a is set to, for example, 0.7, which is a low supercharging state.

On the other hand, when the electromagnetic clutch of the crankshaft pulley 34 is connected and the electromagnetic clutch of the pump shaft pulley 35 is disconnected, the crankshaft 31 rotates from the large diameter pulley 34 for the crankshaft to the belt 37. Is transmitted to the input shaft 13a of the supercharger 13, and the rotation ratio of the input shaft 13a to the crankshaft 31 at this time is set to a high supercharging state of 1.4, for example.

The change of the operating state of the supercharger 13, that is, the switching between the stopped state, the low supercharging state and the high supercharging state is carried out, for example, in the state shown in FIG. That is, the throttle opening as the engine load is parameterized.
When the throttle opening is smaller than the predetermined opening TV1, the supercharger 13 is stopped, and when the throttle opening is between TV1 and TV2 (TV1 <TV2), The supercharger 13 is in a low supercharging state. Further, when the throttle opening is larger than TV2, the supercharger 13 is in the high supercharging state.

The ABV 21 is basically a supercharger.
It can be fully opened when the jar 13 is in a stopped state (all intake air flows to the intercooler 14 through the bypass passage 20) and fully closed when the supercharger 13 is in a driven state ( All intake air is supercharger 13
Through to the interlacer 14). However, in the embodiment, in order to prevent a large torque change due to the switching of the operating state of the supercharger 13, the ABV 21 is set to the position shown in FIG.
The opening degree is adjusted (controlled) as shown in FIG. That is, the solid line in FIG. 3 is the torque curve obtained in the present embodiment using the opening adjustment of the ABV 21, the two-dot chain line is the torque curve at the time of natural intake (NA), and the broken line is the low supercharging state. It is a torque curve, and the alternate long and short dash line is the torque curve in the high supercharging state.

In order to obtain the torque curve shown by the solid line in FIG. 3, as the throttle opening gradually increases from the fully closed state, the ABV 21 is gradually closed from the fully opened state near the TV 1. Then, when it is near TV2, it is almost fully closed, and is fully closed at the time of TV2. And T
At the time of V2, in synchronization with the supercharger 13 being switched from the low supercharging state to the high supercharging state, the ABV 21 is opened by a predetermined opening (an opening for preventing a torque step, in the embodiment, about 75%), thereafter, the ABV 21 is gradually closed as the throttle opening is increased, and is fully closed at a predetermined time point before the throttle opening is fully opened. It should be noted that while the supercharger 13 is being driven, the ABV 21
When the valve is opened, a part of the supercharged air supercharged by the supercharger 13 is returned to the suction side of the supercharger 13 through the bypass passage 20. The torque is reduced by that amount.

FIG. 2 shows a control system in the configuration shown in FIG. In FIG. 2, U is a control unit configured by using a microcomputer, and a throttle opening signal from the throttle sensor S1 and an air flow signal.
Intake air amount signal from the sensor 11, crank angle signal (for TDC detection) from the sensor S2, pressure signal from the sensor 16, NO intake temperature signal from the sensor 17, supercharger 13 rotation speed signal from the sensor 18. , The engine speed signal from the sensor S3, the opening signal of the ABV 21 from the sensor S4, etc. are input. In addition, from the control unit U,
A fuel injection amount signal for the fuel injection valve 15, an ignition timing signal for the spark plug 6, an opening signal for the ABV 21, an electromagnetic clutch on / off signal for the variable pulleys 34, 35, etc. are output.

In the control by the control unit U, the actual intake air amount sucked into the cylinder, that is, the combustion chamber 1 is calculated based on the intake air amount signal output from the air flow meter 11, and this is calculated. A fuel injection amount signal is output so as to obtain a predetermined air-fuel ratio in accordance with the calculated intake air amount. Hereinafter, based on the output of the air flow meter 11, the fuel is injected into the combustion chamber 1. The actual intake air amount calculation (filling efficiency calculation) performed will be described. Of the signals input to the control unit U, the supercharger rotation speed signal indicates the actual operating state of the supercharger 13.
It is used for confirmation while considering the engine speed signal.

The control contents of the intake air amount calculation by the control unit U will be described with reference to the flowcharts of FIGS. 4 to 7. In the following description, P indicates a step. First, FIG. 4 shows an interrupt process every 1 msec.
, The output signal from the air flow meter 11 is A /
After D conversion, the maximum intake air amount between TDC (top dead center) is calculated at P2.

In FIG. 5, the control is started at the time of TDC. First, in P11, the digital signal value indicating the maximum intake air amount obtained in P2 is converted into a physical amount indicating the intake air amount. Next, at P12, the apparent volume efficiency V ₀ is calculated based on the physical quantity at P11.
At P13, as will be described later, the smoothing coefficient K1 is set according to the operating state of the supercharger 13. P14
Then, the smoothing coefficient K1 (K1 <1) is used to calculate the intake air amount after the smoothing, that is, the volumetric efficiency V _n according to the equation shown here. In this formula, V _n-1 is the previously obtained volume efficiency, and the meaning of this formula is that the previous volume efficiency V _{n- 1} is reflected by the proportion of the averaging coefficient K1. It means that the larger the smoothing coefficient K1, the larger the smoothing degree (the greater the degree of reflection of the past volume efficiency, that is, the past intake air amount).

At P15, as will be described later, after the pulsation correction coefficient K2 is set according to the operating state of the supercharger 13, at P16, the correction coefficient K2 is added to the volumetric efficiency V _n obtained at P14. The multiplication is performed to calculate the volumetric efficiency V _n after the pulsation correction. Then, in P17, the charging efficiency, that is, the amount of intake air actually sucked into the combustion chamber 1 is calculated based on the volumetric efficiency V _n after the pulsation correction and the intake air temperature.

FIG. 6 shows details of the setting of the smoothing coefficient in P13 of FIG. That is, in P21, it is determined whether or not the supercharger 13 is driven. If the determination in P21 is NO, the smoothing coefficient K1 is set to that for the stopped state, that is, that for the naturally aspirated state (the one obtained in advance by experiments). If YES in the determination in P21, the opening abvp (%) of the ABV 21 is read in P23, and then in P24, it is determined whether or not the low speed pulley ratio (low supercharging state). To be done. When the determination in P24 is YES, in P25, the smoothing coefficient K1 in the low supercharging state is set according to the equation shown here. If NO in P26, the smoothing coefficient K1 in the high supercharging state is set in P26 according to the equation shown here.

In the formulas shown in P25 and P26,
“KSCOP” is a smoothing coefficient when the supercharger 13 is in a driving state (regardless of the low supercharging state and the high supercharging state) and the ABV 21 is fully opened. "KSCLCL" is
The supercharger 13 is in a low supercharging state and the ABV21
Is the smoothing coefficient when is fully closed. "KSCHCL"
Indicates that the supercharger 13 is in a high supercharging state and ABV
21 is a smoothing coefficient when fully closed. Each smoothing coefficient “KSCOP”, “KSCLCL” and “KSCHC”
Each L ”is experimentally obtained in advance.

8 and 9, the apparent volumetric efficiency, the intake pressure detected by the pressure sensor 16, and the charging efficiency change when the throttle opening is changed from fully closed to fully open. FIG. 8 shows the state of natural intake, and FIG. 9 shows the state of low supercharging. In the embodiment, the moderating coefficient for obtaining the filling efficiency based on the maximum apparent volumetric efficiency is 98.05% in the case of natural aspiration and 97.80% in the low supercharging state. Although the difference is as small as "0.25%", the difference is about 10% in the filling efficiency calculation result. 8 and 9 in the high supercharging state are not shown in the figure, the annealing coefficient in the high supercharging state is 96.00 in the embodiment.
%.

The details of P15 in FIG. 5 are shown in FIG.
That is, in P31, it is determined whether or not the supercharger 13 is in the driving state. If the determination in P31 is no, in P342, the correction coefficient K2 for natural intake is set. If YES in the determination in P31,
At P33, it is determined whether or not the low-speed pulley ratio, that is, the low supercharging state is present. If YES in the determination in P33, the correction coefficient K2 for the low supercharging state is set in P34.
Is set. If NO in P33, P3
5, the correction coefficient K2 for the high supercharging state is set.

An example of a map for setting the correction coefficient K2 at P32, P34, or P35 is shown in FIG.
This FIG. 10 is set for each engine speed. Then, at P36, the volumetric efficiency is collated with the correction map according to the engine speed of the correction map according to the operating state of the supercharger 13, and the correction coefficient K2 is finally determined. The correction coefficient K2 is shown as the pulsation correction amount (%).

Although the embodiments have been described above, the present invention is not limited to this, and includes, for example, the following cases. (1) Instead of the operating state of the supercharger 13, the smoothing coefficient may be changed according to the intake pressure detected by the pressure sensor 16. In this case, the larger the detected pressure, the smaller the flow delay of the intake air. Therefore, when the pressure is large, the smoothing coefficient may be made smaller than when it is small. The pressure detection position is the pressure downstream of the variable member and is not easily affected by pressure fluctuations near the intake port 2, for example, the pressure in the volume expansion part such as the intercooler 14 or surge tank. And the position immediately downstream thereof is preferable. Note that it is preferable to change the smoothing coefficient in accordance with the intake pressure in order to accurately detect the intake air amount, as shown in FIGS. 8 and 9, a change in intake pressure corresponds to a change in charging efficiency. It is clear from the relationship. (2) The supercharger 13 is not limited to the Lisholm type (screw type), but may be an appropriate type such as a roots type. (3) The turbocharger may be an exhaust turbocharger. In this case, for example, as is often seen recently, a plurality of exhaust turbochargers are provided so that some exhaust turbochargers are stopped at low speeds and all exhaust turbochargers at high speeds. In the case of operating the feeder, when the flow path of the intake air is changed between the low speed and the high speed, the one that causes a difference in the flow delay of the intake air is an application target of the present invention. (4) The present invention is applicable to not only the variable member of the supercharger but also any variable member such as a variable variable intake passage capacity or intake resistance. For example,
When performing dynamic supercharging of intake air (inertial supercharging or resonance supercharging),
In order to switch the tuning speed according to the engine speed, if a volume expansion part is separately connected to the intake passage via an on-off valve, and if the intake passage capacity is variable and the intake flow delay changes, The present invention can be applied. Further, when the dynamic supercharging of the intake air is switched in multiple stages by switching the intake passage, the intake passage resistance is changed, so that the present invention can be applied to this case as well. (5) The throttle valve 12 can be arranged at any position on the upstream side of the variable member such as the supercharger 13 or the lower eye. (6) As the operating state of the supercharger 13 as a variable member, only switching is performed in two stages of a stopped state and a supercharged state, or in two stages of a low supercharged state and a high supercharged state. In addition, the supercharging state may be switched in three or more stages.

[Brief description of drawings]

FIG. 1 is an overall system diagram showing an embodiment of the present invention.

FIG. 2 is a control system diagram used in FIG.

FIG. 3 is a diagram showing a relationship between an operating state of a supercharger and an opening setting of a bypass passage.

FIG. 4 is a flow chart showing a control example of the present invention.

FIG. 5 is a flow chart showing a control example of the present invention.

FIG. 6 is a flow chart showing a control example of the present invention.

FIG. 7 is a flow chart showing a control example of the present invention.

FIG. 8 is a diagram showing a relationship between apparent volumetric efficiency, intake pressure and charging efficiency with respect to a change in throttle opening in a natural intake state.

FIG. 9 is a diagram corresponding to FIG. 8 in a low supercharging state.

FIG. 10 is a diagram showing an example of setting a map for pulsation correction according to the operating state of the supercharger.

[Description of sign]

 E: Engine U: Control unit 1: Combustion chamber (cylinder) 10: Intake passage 11: Air flow meter (intake air amount detection means) 12: Throttle valve 13: Supercharger (variable member) 16: Pressure Sensor 20: Bypass passage 21: ABV (for bypass passage opening adjustment) 34: Pulley (for small diameter and low supercharging state) 35: Pulley (for large diameter and high supercharging state)

Claims (19)

[Claims] 1. An engine provided with an intake air amount detecting means provided in an intake passage of an engine and an averaging means for smoothing an output of the intake air amount detecting means, wherein the intake passage of the engine is provided with: A variable member that affects the flow delay of the intake air between the intake air amount detection means and the cylinder is disposed, and the moderation degree in the smoothing processing means is changed according to the operating state of the variable member. An intake air amount control device for an engine, comprising a degree changing means. 2. An engine comprising an intake air amount detecting means provided in an intake passage of the engine and an averaging means for smoothing an output of the intake air amount detecting means, wherein the intake passage of the engine is provided with: A variable member that affects the flow delay of the intake air between the intake air amount detection means and the cylinder is provided, and a pressure detection means for detecting the pressure of the intake passage downstream of the variable member is provided. An intake air amount control device for an engine, comprising: a smoothing degree changing means for changing a smoothing degree in the smoothing processing means in accordance with a detected pressure. 3. An engine provided with intake air amount detecting means provided in an intake passage of the engine and smoothing means for smoothing an output of the intake air amount detecting means, wherein a predetermined amount is provided in the intake passage of the engine. Is provided with a supercharger whose operating state is changed in accordance with the condition, and is provided with an annealing degree changing means for changing the annealing degree in the annealing processing means in accordance with the operating state of the supercharger. An intake air amount control device for an engine, comprising: 4. The turbocharger according to claim 3, wherein the operation state of the supercharger is changed at least between a stopped state and a supercharged state, and the smoothing degree changing means sets the operation state to the stopped state. Change the degree of smoothing between the supercharged state. 5. The supercharger according to claim 3, wherein the operating state is set so as to be changed at least between a low supercharging state and a high supercharging state, and the smoothing degree changing means includes: Changing the degree of smoothing between a low supercharging state and a high supercharging state. 6. The turbocharger according to claim 5, wherein the supercharger is mechanically driven by an engine.
A rotation ratio changing means for changing the rotation ratio of the supercharger with respect to the engine speed is interposed in the drive system path of the supercharger. It is set so that the supercharged state and the high supercharged state can be switched. 7. The engine according to claim 6, wherein the rotation ratio changing means is set to a high rotation ratio, that is, a high supercharging state when the engine is under a heavy load. 8. The smoothing degree according to any one of claims 5 to 7 when the high supercharging state is higher than that in the low supercharging state as compared with the low supercharging state. What is made smaller. 9. The bypass passage for bypassing the supercharger according to claim 3, wherein an intake passage between the intake air amount detecting means and the cylinder is provided with a bypass passage. An opening degree adjusting means for adjusting the opening degree of the bypass passage is provided, and the smoothing degree changing means changes the smoothing degree in consideration of the opening degree of the opening degree adjusting means. 10. The opening degree adjusting means according to claim 9, wherein the opening degree adjusting means is set so as to gradually change the torque generated by the engine when the operating state of the supercharger is changed. What you have. 11. The smoothing degree changing means according to claim 1, wherein the smoothing degree changing means reduces the smoothing degree when the flow delay is small depending on the operating state of the variable member, compared to when the flow delay is large. 12. The smoothing degree changing means according to claim 2, wherein the smoothing degree changing means reduces the smoothing degree when the pressure detected by the pressure detecting means is large compared to when the pressure is small. 13. An engine comprising: an intake air amount detecting means provided in an intake passage of the engine; and a pulsation correcting means for correcting an output of the intake air amount detecting means in accordance with a pulsation of the intake air. A variable member that affects the pulsation of the intake air between the intake air amount detecting means and the cylinder is disposed in the passage, and a correction that changes the degree of correction in the pulsation correcting means according to the operating state of the variable member. An intake air amount control device for an engine, comprising a degree changing means. 14. The variable member according to claim 13, wherein the variable member is a supercharger mechanically driven by an engine, and a pulsation state of intake air is changed by changing an operating state of the supercharger. What is changed. 15. The correction degree changing means according to claim 14, wherein the supercharger is set so that an operating state is changed between a stopped state, a low supercharging state, and a high supercharging state. However, the correction degree is changed between the stopped state, the low supercharging state and the high supercharging state. 16. An annealing device for performing an annealing process on an intake air amount detecting means provided in an intake passage of an engine and an intake air amount signal output from the intake air amount detecting means using a predetermined smoothing coefficient. And a pulsation correcting means for correcting the intake air amount signal after the smoothing processing by the smoothing means according to intake pulsation using a predetermined correction coefficient, and the pulsation correcting means arranged in the intake passage of the engine. A supercharger that is mechanically driven by an engine; operating state changing means that changes the operating state of the supercharger; and the anneal according to the operating state of the supercharger. A smoothing coefficient setting means for setting the smoothing coefficient used by the processing means; and a correction coefficient setting means for setting the correction coefficient used by the correcting means in accordance with the operating state of the supercharger. Features and Intake air amount control apparatus that the engine. 17. The operating state changing means according to claim 16, wherein the operating state changing means changes the operating state of the supercharger between three states of a stopped state, a low supercharging state and a high supercharging state. And the smoothing coefficient and the correction coefficient are set according to the three operating states. 18. A bypass passage for bypassing the supercharger is provided in an intake passage between the intake air amount detecting means and a cylinder, and an opening for adjusting an opening of the bypass is provided. A degree adjusting means is provided, and the moderating coefficient is set in consideration of the opening degree of the opening degree adjusting means. 19. The opening degree adjusting means according to claim 18, which is fully opened when the supercharger is in a stopped state, and is generated in the engine when the operating state of the supercharger is switched. It is set so that the opening is adjusted so that the torque gradually changes.