JP2006009745A - Method for correcting output of air flow sensor for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for correcting output of an air flow sensor of an internal combustion engine capable of correcting output drop due to adhesion of foreign matter on a detection part of the air flow sensor, performing control of EGR quantity or the like appropriately, and coping with a future stringent exhaust emission regulation. <P>SOLUTION: At a time of EGR cut, engine speed detected by a rotation speed sensor 18, estimated intake air quantity Q<SB>0</SB>estimated based on load W (accelerator opening in this embodiment) detected by an accelerator sensor 19, and difference ΔQ(=Q<SB>0</SB>-Q) from intake air quantity Q detected by the air flow sensor 16 are determined, output of the air flow sensor 16 is corrected in an increase direction if the difference ΔQ exceeds preset threshold. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an air flow sensor output correction method for an internal combustion engine.

  Conventionally, in an internal combustion engine such as an automobile diesel engine, a part of exhaust gas is extracted from the exhaust side and returned to the intake side, and the exhaust gas returned to the intake side is used to suppress the combustion of fuel in the engine. So-called exhaust gas recirculation (EGR) is performed in which generation of NOx is reduced by lowering the combustion temperature.

  In general, when this type of exhaust gas recirculation is performed, an appropriate position of the exhaust passage from the exhaust manifold to the exhaust pipe and an appropriate position of the intake passage from the intake pipe to the intake manifold are connected by an EGR pipe. The exhaust gas is recirculated through the EGR pipe.

  In addition, if the exhaust gas recirculated to the engine is cooled in the middle of the EGR pipe, the temperature of the exhaust gas is reduced and the volume thereof is reduced, so that the combustion temperature is effectively reduced without significantly reducing the output of the engine. Since the generation of nitrogen oxides can be reduced, a water-cooled EGR cooler is provided in the middle of an EGR pipe for recirculating exhaust gas to the engine.

  In the case of the engine as described above, a turbocharger such as a so-called VG (Variable Geometry) turbocharger in which a number of nozzle vanes capable of adjusting the angle are arranged in the throat portion of the turbine scroll passage, and particulates in the exhaust gas. Many of them are equipped with a particulate filter that collects.

  By the way, in recent years, exhaust gas regulations tend to become stricter. In order to comply with such exhaust gas regulations, control of EGR valve, nozzle vane opening degree of supercharger such as VG turbocharger, etc. Although it is necessary to perform each in detail, it is extremely important to provide an airflow sensor in the middle of the intake pipe and detect the intake air amount by the airflow sensor when performing these controls.

For example, Patent Document 1 discloses an internal combustion engine including an airflow sensor, an EGR device, a supercharger, a particulate filter, and the like as described above.
JP 2003-49633 A

  As the air flow sensor, a hot wire probe (hot wire) for detecting the amount of intake air and a temperature probe for detecting the air temperature are usually installed inside the intake pipe on the downstream side of the air cleaner. A so-called hot wire type air flow sensor is used in which a current is passed through a hot wire probe so that the temperature difference of the air temperature probe is always constant, and the voltage value at that time is output as an air flow sensor signal.

  However, if foreign matter such as fine carbon or oil mist that has passed through the air cleaner element adheres to the detection part such as the hot wire of the air flow sensor and accumulates over time, it will be compared with the actual intake air amount. As a result, the detected value becomes a low value, so that the control is advanced in the direction of decreasing the EGR amount because more intake air is required. In particular, the generation of NOx cannot be sufficiently suppressed, and there is a possibility that the exhaust gas regulation cannot be applied.

  In view of such circumstances, the present invention can correct a decrease in output due to foreign matter adhering to the detection unit of the airflow sensor, can appropriately control the EGR amount, etc. An object of the present invention is to provide a method for correcting the output of an air flow sensor for an internal combustion engine that can be used.

The invention according to claim 1 includes an air flow sensor that detects an intake air amount, an EGR device that recirculates a part of the exhaust gas to the intake side, and a particulate filter that collects particulates in the exhaust gas. An air flow sensor output correction method for an internal combustion engine comprising:
At the time of EGR cut, a deviation between the predicted intake air amount predicted to be inhaled based on the engine speed and the load and the intake air amount detected by the air flow sensor is obtained, and the deviation is set to a preset threshold value. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected in a direction to increase when the air flow sensor exceeds the value.

  According to the first aspect of the invention, the following operation can be obtained.

  Since only fresh air is introduced into the engine at the time of EGR cut, a predicted intake air amount that is predicted to be inhaled at that time is obtained based on the engine speed and load. Using the intake air amount, obtaining a deviation from the intake air amount detected by the air flow sensor, and correcting the direction in which the output of the air flow sensor is increased when the deviation exceeds a preset threshold, Even if foreign matter such as fine carbon or oil mist that has passed through the air cleaner element adheres to the detection part such as the hot wire of the airflow sensor and accumulates over time, the actual intake air It is avoided that the detected value becomes lower than the amount, and the amount of EGR is reduced because more intake air is required. Without the control direction is advanced, will form control is continuously performed properly, the generation of NOx is sufficiently suppressed, and adaptable to the exhaust gas regulations.

The invention according to claim 2 includes an air flow sensor that detects the amount of intake air, an EGR device that recirculates part of the exhaust gas to the intake side, and a particulate filter that collects particulates in the exhaust gas. An air flow sensor output correction method for an internal combustion engine comprising:
At the time of EGR cut, a ratio between a predicted intake air amount predicted to be inhaled based on an engine speed and a load and an intake air amount detected by an air flow sensor is obtained, and the ratio is a preset threshold value An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected in a direction to increase when the air flow sensor exceeds the value.

  According to the second aspect of the invention, the following operation can be obtained.

  Since only fresh air is introduced into the engine at the time of EGR cut, a predicted intake air amount that is predicted to be inhaled at that time is obtained based on the engine speed and load. When the ratio of the intake air amount is used to obtain the ratio of the intake air amount detected by the air flow sensor and the ratio exceeds a preset threshold value, the output of the air flow sensor is corrected in the increasing direction. Even if foreign matter such as fine carbon or oil mist that has passed through the air cleaner element adheres to the detection part such as the hot wire of the airflow sensor and accumulates over time, the actual intake air It is avoided that the detected value becomes lower than the amount, and the amount of EGR is reduced because more intake air is required. Without the control direction is advanced, will form control is continuously performed properly, the generation of NOx is sufficiently suppressed, and adaptable to the exhaust gas regulations.

The invention according to claim 3 is an air flow sensor that detects the amount of intake air, an EGR device that recirculates a portion of the exhaust gas to the intake side, a supercharger that supercharges intake air, and a partition in the exhaust gas. An air flow sensor output correction method for an internal combustion engine comprising a particulate filter for collecting curate,
At the time of EGR cut, the deviation between the predicted intake air amount predicted to be sucked based on the engine speed and the supercharger rotation speed and the intake air amount detected by the air flow sensor is obtained, and the deviation is determined in advance. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected so as to increase when the set threshold value is exceeded.

  According to the third aspect of the invention, the following operation can be obtained.

  Since only fresh air is introduced into the engine at the time of EGR cut, a predicted intake air amount that is predicted to be sucked at that time is determined based on the engine speed and the turbocharger speed. Therefore, using the predicted intake air amount, a deviation from the intake air amount detected by the air flow sensor is obtained, and when the deviation exceeds a preset threshold, the output of the air flow sensor is corrected to increase. Then, even if foreign matter such as fine carbon or oil mist that has passed through the air cleaner element adheres to the detection part such as the hot wire of the air flow sensor, and it has accumulated over time, It is avoided that the detected value becomes lower than the actual intake air amount, and the EGR amount is set as more intake air is necessary. Without the control direction causing lack is advanced, will form control is continuously performed properly, the generation of NOx is sufficiently suppressed, and adaptable to the exhaust gas regulations.

According to a fourth aspect of the present invention, there is provided an air flow sensor for detecting an intake air amount, an EGR device for recirculating a part of exhaust gas to the intake side, a supercharger for supercharging intake air, and a partition in exhaust gas. An air flow sensor output correction method for an internal combustion engine comprising a particulate filter for collecting curate,
At the time of EGR cut, a ratio between the estimated intake air amount predicted to be sucked based on the engine speed and the turbocharger speed and the intake air amount detected by the air flow sensor is obtained, and the ratio is calculated in advance. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected so as to increase when the set threshold value is exceeded.

  According to the fourth aspect of the invention, the following operation can be obtained.

  Since only fresh air is introduced into the engine at the time of EGR cut, a predicted intake air amount that is predicted to be sucked at that time is determined based on the engine speed and the turbocharger speed. Therefore, using the predicted intake air amount, a ratio with the intake air amount detected by the air flow sensor is obtained, and when the ratio exceeds a preset threshold, the output of the air flow sensor is corrected to increase. Then, even if foreign matter such as fine carbon or oil mist that has passed through the air cleaner element adheres to the detection part such as the hot wire of the air flow sensor, and it has accumulated over time, It is avoided that the detected value becomes lower than the actual intake air amount, and the EGR amount is set as more intake air is necessary. Without the control direction causing lack is advanced, will form control is continuously performed properly, the generation of NOx is sufficiently suppressed, and adaptable to the exhaust gas regulations.

The invention according to claim 5 is an air flow sensor that detects the amount of intake air, an EGR device that recirculates part of the exhaust gas to the intake side, a supercharger that supercharges intake air, and a partition in exhaust gas. An air flow sensor output correction method for an internal combustion engine comprising a particulate filter for collecting curate,
At the time of EGR cut, the deviation between the predicted intake air amount predicted to be sucked based on the engine speed and the boost pressure and the intake air amount detected by the air flow sensor is obtained, and the deviation is set in advance. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected so as to increase when the threshold value is exceeded.

  According to the fifth aspect of the present invention, the following operation is obtained.

  Since only fresh air is introduced into the engine at the time of EGR cut, a predicted intake air amount that is predicted to be sucked at that time is determined based on the engine speed and the boost pressure. Using the predicted intake air amount, a deviation from the intake air amount detected by the air flow sensor is obtained, and when the deviation exceeds a preset threshold value, the output of the air flow sensor is corrected so as to increase. Even if foreign matter such as fine carbon or oil mist that has passed through the air cleaner element adheres to the detection part such as the hot wire of the air flow sensor and accumulates over time, It is avoided that the detected value becomes lower than the intake air amount, and the EGR amount is reduced because more intake air is required. Without the control direction is advanced that the control is in the form that is continuously performed properly, the generation of NOx is sufficiently suppressed, and adaptable to the exhaust gas regulations.

The invention according to claim 6 is an air flow sensor that detects the amount of intake air, an EGR device that recirculates part of the exhaust gas to the intake side, a supercharger that supercharges intake air, and a partition in the exhaust gas. An air flow sensor output correction method for an internal combustion engine comprising a particulate filter for collecting curate,
At the time of EGR cut, a ratio between a predicted intake air amount predicted to be inhaled based on the engine speed and the boost pressure and an intake air amount detected by the air flow sensor is obtained, and the ratio is set in advance. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected so as to increase when the threshold value is exceeded.

  According to the invention which concerns on the said Claim 6, the following effects | actions are acquired.

  Since only fresh air is introduced into the engine at the time of EGR cut, a predicted intake air amount that is predicted to be sucked at that time is determined based on the engine speed and the boost pressure. Using the predicted intake air amount, a ratio with the intake air amount detected by the air flow sensor is obtained, and when the ratio exceeds a preset threshold, the output of the air flow sensor is corrected to increase. Even if foreign matter such as fine carbon or oil mist that has passed through the air cleaner element adheres to the detection part such as the hot wire of the air flow sensor and accumulates over time, It is avoided that the detected value becomes lower than the intake air amount, and the EGR amount is reduced because more intake air is required. Without the control direction is advanced that the control is in the form that is continuously performed properly, the generation of NOx is sufficiently suppressed, and adaptable to the exhaust gas regulations.

  According to the air flow sensor output correction method for an internal combustion engine according to claims 1 to 6 of the present invention, it is possible to correct a decrease in output due to foreign matter adhering to the detection portion of the air flow sensor, and to appropriately control the EGR amount and the like. Therefore, it is possible to achieve an excellent effect of being able to cope with strict exhaust gas regulations in the future.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a first example of an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an engine which is a diesel internal combustion engine, and the engine 1 includes a supercharger 2 such as a VG turbocharger. The intake air 4 guided from the air cleaner 3 is sent to the compressor 2a of the supercharger 2 through the intake pipe 5, and the intake air 4 pressurized by the compressor 2a is sent to the intercooler 6 to be cooled. The intake air 4 is guided to the intake manifold 7 and distributed to each cylinder 8 of the engine 1 (the case of in-line 6 cylinders is illustrated in FIG. 1).

  Further, exhaust gas 9 discharged from each cylinder 8 of the engine 1 is sent to the turbine 2b of the supercharger 2 through the exhaust manifold 10, and the exhaust gas 9 driving the turbine 2b is sent to the outside of the vehicle through the exhaust pipe 11. To be discharged.

  In the middle of the exhaust pipe 11, a catalyst regeneration type particulate filter 12 on which an oxidation catalyst is integrally supported is provided, and particulates (particulate matter) contained in the exhaust gas 9 are contained in the exhaust pipe 9. Collection is performed by the particulate filter 12.

  Further, the exhaust manifold 10 is connected to both ends of the exhaust manifold 10 in the arrangement direction of the cylinders 8 and one end of the intake pipe 5 connected to the intake manifold 7 by an EGR pipe 13. A part of the gas 9 is recirculated to the intake pipe 5 through the water-cooled EGR cooler 14 and the EGR valve 15, and the recirculated exhaust gas 9 suppresses the combustion of fuel in each cylinder 8. Generation of NOx is reduced by lowering the combustion temperature.

On the other hand, an airflow sensor 16 for detecting the intake air amount Q is provided in the middle of the intake pipe 5 between the air cleaner 3 and the compressor 2a of the supercharger 2, and the intake air amount Q detected by the airflow sensor 16 is used as the engine. Input to a control device 17 forming a control computer (ECU: Electronic Control Unit), and during normal operation, the control device 17 performs an operation such as comparing the intake air amount Q with a set value, and depending on the deviation, etc. The EGR valve 15 and the nozzle vane opening degree of the supercharger 2 such as a VG turbocharger are controlled by various control signals (not shown) output from the controller 17. The features of the illustrated example are that the engine speed N detected by the rotation sensor 18 and the load W detected by the accelerator sensor 19 (acceleration in this example) during EGR cut. The predicted intake air amount Q ₀ which is predicted to be sucked on the basis of the opening), a deviation Delta] Q (= Q ₀ -Q) of the detected intake air amount Q by the air flow sensor 16, the The difference is that when the deviation ΔQ exceeds a preset threshold value, the output of the airflow sensor 16 is corrected in the direction of increasing.

  The load W can use a fuel injection amount instead of the accelerator opening detected by the accelerator sensor 19.

  Further, the increment when correcting the output of the air flow sensor 16 is appropriately adjusted according to the degree to which the deviation ΔQ exceeds a preset threshold value.

  Furthermore, the EGR cut may cause damage to the intake system if high concentration HC injected by post injection or the like during forced regeneration of the particulate filter 12 is returned to the intake system. This is performed by temporarily closing the EGR valve 15 for the purpose of protecting the intake system from the concentration HC.

  Next, the operation of the illustrated example will be described.

Since only fresh air is introduced into the engine 1 at the time of EGR cut, the predicted intake air amount Q ₀ predicted to be sucked at that time based on the engine speed N and the load W is Since it is obtained from a map stored in advance in the memory of the control device 17, a deviation ΔQ from the intake air amount Q detected by the airflow sensor 16 is obtained using the predicted intake air amount Q ₀ , and the deviation ΔQ is set in advance. If the output of the air flow sensor 16 is corrected to increase in the case where the threshold value is exceeded, even if foreign matter such as fine carbon or oil mist that has passed through the elements of the air cleaner 3 is Even if it adheres to a detection part such as a hot wire and accumulates over time, the detected value is lower than the actual intake air amount Q. The control is not continued in the direction of decreasing the EGR amount because more intake air is required, and the control is properly continued, and NOx is generated. Sufficiently suppressed and adaptable to exhaust gas regulations.

  It should be noted that when no foreign matter adheres to the detection unit such as the hot wire of the air flow sensor 16 and the deviation ΔQ obtained at the time of EGR cut is equal to or less than a preset threshold value, or the hot wire of the air flow sensor 16 In the case where the foreign matter accumulated in the detection unit or the like falls off and the deviation ΔQ obtained at the time of EGR cut becomes equal to or less than a preset threshold value, the intake air amount Q detected by the air flow sensor 16 is It is used as it is without correction.

  In this way, it is possible to correct a decrease in output due to foreign matter adhering to the detection portion of the air flow sensor 16, to appropriately control the EGR amount, and to cope with severe exhaust gas regulations in the future.

Incidentally, in the example shown in FIG. 1, the predicted intake air amount Q ₀ predicted to be inhaled based on the engine speed N and the load W at the time of EGR cut, and the intake air detected by the air flow sensor 16 A ratio γ (= Q ₀ / Q) with the quantity Q is obtained, and when the ratio γ exceeds a preset threshold value, the output of the airflow sensor 16 may be corrected so as to increase. Thus, even if the ratio γ is used instead of the deviation ΔQ, the same effect as described above can be obtained.

FIG. 2 is a second example of an embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same components, and the basic configuration is the same as that shown in FIG. However, as shown in FIG. 2, the feature of this illustrated example is that the engine speed N detected by the rotation sensor 18 and the supercharger speed N detected by the supercharger rotation sensor 20 at the time of EGR cut. A deviation ΔQ between the predicted intake air amount Q ₀ predicted to be inhaled based on _T and the intake air amount Q detected by the air flow sensor 16 is obtained, and the deviation ΔQ exceeds a preset threshold value In this case, the output of the air flow sensor 16 is corrected in the direction of increasing.

  As in the example shown in FIG. 1, the increment when correcting the output of the air flow sensor 16 is adjusted as appropriate according to the degree to which the deviation ΔQ exceeds a preset threshold value.

  Similarly to the example shown in FIG. 1, the EGR cut causes damage to the intake system when, for example, high concentration HC injected by post injection or the like during forced regeneration of the particulate filter 12 is returned to the intake system. In order to protect the intake system from the high-concentration HC, this is performed by temporarily closing the EGR valve 15.

  Next, the operation of the example shown in FIG. 2 will be described.

Since only fresh air is introduced into the engine 1 at the time of EGR cut, the predicted intake air that is predicted to be sucked at that time based on the engine speed N and the turbocharger speed _NT Since the amount Q ₀ is obtained from a map stored in advance in the memory of the control device 17, the predicted intake air amount Q ₀ is used to obtain a deviation ΔQ from the intake air amount Q detected by the air flow sensor 16, When the deviation ΔQ exceeds a preset threshold value, if the correction is made in the direction of increasing the output of the air flow sensor 16, foreign matter such as fine carbon or oil mist that has passed through the elements of the air cleaner 3 will be detected. Even if it adheres to a detection part such as a hot wire of the air flow sensor 16 and accumulates over time, the detected value is lower than the actual intake air amount Q. As the amount of intake air is required, the control is not continued in the direction of decreasing the EGR amount, and the control is appropriately continued. Is sufficiently suppressed, and can be adapted to exhaust gas regulations.

  As in the example shown in FIG. 1, when no foreign matter is attached to the detection unit such as a hot wire of the air flow sensor 16 and the deviation ΔQ obtained at the time of EGR cut is equal to or less than a preset threshold value, or When the foreign matter accumulated on the detection unit such as the hot wire of the air flow sensor 16 falls off and the deviation ΔQ obtained at the time of EGR cut becomes equal to or less than a preset threshold value, the air flow sensor 16 The detected intake air amount Q is used without correction.

  Thus, in the case of the example shown in FIG. 2, similarly to the example shown in FIG. 1, it is possible to correct a decrease in output due to the adhesion of foreign matter to the detection unit of the airflow sensor 16, and to properly control the EGR amount, etc. It can respond to strict exhaust gas regulations in the future.

Incidentally, in the example shown in FIG. 2, the predicted intake air amount Q ₀ predicted to be inhaled based on the engine speed N and the supercharger speed _NT at the time of EGR cut, and the air flow sensor 16 A ratio γ (= Q ₀ / Q) with the detected intake air amount Q is obtained, and when the ratio γ exceeds a preset threshold value, the output of the air flow sensor 16 is corrected so as to increase. Even if the ratio γ is used instead of the deviation ΔQ in this way, the same effect as described above can be obtained.

FIG. 3 shows a third example of an embodiment of the present invention. In the figure, the same reference numerals as those in FIGS. 1 and 2 denote the same components, and the basic configuration is shown in FIGS. 2 is the same as that shown in FIG. 2 but is characterized by the engine speed N detected by the rotation sensor 18 and the boost pressure detected by the boost sensor 21 during EGR cut as shown in FIG. A deviation ΔQ between the predicted intake air amount Q ₀ predicted to be inhaled based on P and the intake air amount Q detected by the air flow sensor 16 is obtained, and the deviation ΔQ exceeds a preset threshold value. In this case, the output of the air flow sensor 16 is corrected in the direction of increasing.

  As in the example shown in FIGS. 1 and 2, the increment when correcting the output of the air flow sensor 16 is adjusted as appropriate according to the degree to which the deviation ΔQ exceeds a preset threshold value. It is.

  Similarly to the example shown in FIGS. 1 and 2, the EGR cut is performed when, for example, high concentration HC injected by post injection or the like during forced regeneration of the particulate filter 12 is returned to the intake system. Since there is a possibility of damaging, the EGR valve 15 is temporarily closed for the purpose of protecting the intake system from the high concentration HC.

  Next, the operation of the example shown in FIG. 3 will be described.

Since only fresh air is introduced into the engine 1 at the time of EGR cut, the predicted intake air amount Q ₀ predicted to be sucked at that time based on the engine speed N and the boost pressure P ₀ but because it is obtained from a map stored in the memory of the control unit 17, using the predicted intake air amount Q _0, a deviation ΔQ between the detected intake air quantity Q by the air flow sensor 16, the deviation ΔQ If correction is made in the direction of increasing the output of the air flow sensor 16 when a preset threshold value is exceeded, even if foreign matter such as fine carbon or oil mist that has passed through the elements of the air cleaner 3 is Even if it adheres to the detection part such as 16 hot wires and accumulates over time, the detected value is lower than the actual intake air amount Q. As a result, the control is not continued in the direction of decreasing the EGR amount because more intake air is required, and the control is appropriately continued, and NOx is generated. Sufficiently suppressed and adaptable to exhaust gas regulations.

  As in the example shown in FIGS. 1 and 2, no foreign matter is attached to the detection unit such as a hot wire of the air flow sensor 16, and the deviation ΔQ obtained at the time of EGR cut is equal to or less than a preset threshold value. In the case where the foreign matter accumulated on the detection unit such as the hot wire of the air flow sensor 16 falls off and the deviation ΔQ obtained at the time of EGR cut becomes equal to or less than a preset threshold value, the air flow The intake air amount Q detected by the sensor 16 is used without being corrected.

  Thus, in the case of the example shown in FIG. 3, as in the example shown in FIGS. 1 and 2, it is possible to correct the output decrease due to the foreign matter adhering to the detection unit of the airflow sensor 16 and to appropriately control the EGR amount and the like. And can meet strict exhaust gas regulations in the future.

Incidentally, in the example shown in FIG. 3, at the time of EGR cut, the predicted intake air amount Q ₀ that is predicted to be sucked based on the engine speed N and the boost pressure P, and the air flow sensor 16 detected. A ratio γ (= Q ₀ / Q) with the intake air amount Q is obtained, and when the ratio γ exceeds a preset threshold value, the output of the air flow sensor 16 may be corrected to increase. Thus, even if the ratio γ is used instead of the deviation ΔQ, the same effect as described above can be obtained.

  The air flow sensor output correction method for an internal combustion engine of the present invention is not limited to the above-described illustrated examples, and it is needless to say that various changes can be made without departing from the scope of the present invention.

It is the schematic which shows the 1st example of the form which implements this invention. It is the schematic which shows the 2nd example of the form which implements this invention. It is the schematic which shows the 3rd example of the embodiment which implements this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Supercharger 4 Intake 5 Intake pipe 7 Intake manifold 9 Exhaust gas 10 Exhaust manifold 11 Exhaust pipe 12 Particulate filter 13 EGR pipe 14 EGR cooler 15 EGR valve 16 Air flow sensor 17 Controller 18 Rotation sensor 19 Acceleration sensor 20 Excess sensor 20 Charger rotation sensor 21 Boost sensor N Engine rotation speed W Load N _T Turbocharger rotation speed P Supercharging pressure Q ₀ Predicted intake air amount Q Intake air amount ΔQ Deviation γ Ratio

Claims (6)

Airflow sensor output correction for an internal combustion engine having an airflow sensor for detecting the amount of intake air, an EGR device for recirculating a part of the exhaust gas to the intake side, and a particulate filter for collecting particulates in the exhaust gas A method,
At the time of EGR cut, a deviation between the predicted intake air amount predicted to be inhaled based on the engine speed and the load and the intake air amount detected by the air flow sensor is obtained, and the deviation is set to a preset threshold value. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected in a direction to increase when the air flow sensor exceeds the limit. Airflow sensor output correction for an internal combustion engine comprising an airflow sensor for detecting the amount of intake air, an EGR device for recirculating a part of the exhaust gas to the intake side, and a particulate filter for collecting particulates in the exhaust gas A method,
At the time of EGR cut, a ratio between a predicted intake air amount predicted to be inhaled based on an engine speed and a load and an intake air amount detected by an air flow sensor is obtained, and the ratio is a preset threshold value An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected in a direction to increase when the air flow sensor exceeds the limit. An air flow sensor that detects the amount of intake air, an EGR device that recirculates part of the exhaust gas to the intake side, a supercharger that supercharges intake air, and a particulate filter that collects particulates in the exhaust gas An air flow sensor output correction method for an internal combustion engine comprising:
At the time of EGR cut, the deviation between the predicted intake air amount predicted to be sucked based on the engine speed and the supercharger rotation speed and the intake air amount detected by the air flow sensor is obtained, and the deviation is determined in advance. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected in a direction to increase when a set threshold value is exceeded. An air flow sensor that detects the amount of intake air, an EGR device that recirculates part of the exhaust gas to the intake side, a supercharger that supercharges intake air, and a particulate filter that collects particulates in the exhaust gas An air flow sensor output correction method for an internal combustion engine comprising:
At the time of EGR cut, a ratio between the estimated intake air amount predicted to be sucked based on the engine speed and the turbocharger speed and the intake air amount detected by the air flow sensor is obtained, and the ratio is calculated in advance. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected in a direction to increase when a set threshold value is exceeded. An air flow sensor that detects the amount of intake air, an EGR device that recirculates part of the exhaust gas to the intake side, a supercharger that supercharges intake air, and a particulate filter that collects particulates in the exhaust gas An air flow sensor output correction method for an internal combustion engine comprising:
At the time of EGR cut, the deviation between the predicted intake air amount predicted to be sucked based on the engine speed and the boost pressure and the intake air amount detected by the air flow sensor is obtained, and the deviation is set in advance. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected so as to increase when the threshold value is exceeded. An air flow sensor that detects the amount of intake air, an EGR device that recirculates part of the exhaust gas to the intake side, a supercharger that supercharges intake air, and a particulate filter that collects particulates in the exhaust gas An air flow sensor output correction method for an internal combustion engine comprising:
At the time of EGR cut, a ratio between a predicted intake air amount predicted to be inhaled based on the engine speed and the boost pressure and an intake air amount detected by the air flow sensor is obtained, and the ratio is set in advance. An air flow sensor output correction method for an internal combustion engine, wherein the output of the air flow sensor is corrected so as to increase when the threshold value is exceeded.

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