WO2008032472A1

WO2008032472A1 - Control device for exhaust gas recirculation valve

Info

Publication number: WO2008032472A1
Application number: PCT/JP2007/060275
Authority: WO
Inventors: Hisashi Yokoyama; Hidetoshi Okada
Original assignee: Mitsubishi Electric Corporation
Priority date: 2006-09-15
Filing date: 2007-05-18
Publication date: 2008-03-20
Also published as: JP2009287392A

Abstract

A control device for an exhaust gas recirculation valve, having an exhaust gas circulation path (20) for interconnecting an intake path (3) of an engine (1) and an exhaust gas path (10) and introducing a part of exhaust gas into the intake path (3), an EGR valve (30) installed in the exhaust gas circulation path (20), and a control unit (50) for controlling the engine (1) and the EGR valve (30). The control unit (50) has an abnormality detection function for detecting an abnormality of the EGR valve (30), and also has a forcible valve open/close function for forcibly opening and closing, based on the abnormality detection by abnormality detection function, the EGR valve (30) independent of normal open/close operation.

Description

Specification

Control device for exhaust gas recirculation valve

Technical field

The present invention relates to a control device for an exhaust gas recirculation valve that returns a part of exhaust gas of an internal combustion engine to an intake system.

Background art

[0002] In order to reduce NOx (nitrogen oxides) of an engine that is an internal combustion engine of an automobile, several methods are used. One example is the exhaust gas recirculation (EGR).

[0003] A conventional exhaust gas recirculation apparatus that uses such an exhaust gas recirculation method includes an exhaust gas recirculation passage that connects an intake passage and an exhaust passage of an engine to introduce a part of the exhaust gas into the intake passage, and the exhaust gas recirculation passage It is configured with an EGR valve that is mounted on the engine and a control unit that controls the engine and EGR valve. Based on the control of the control unit, the EGR valve opens and closes so as to optimize the exhaust gas recirculation amount or exhaust gas recirculation rate in accordance with the engine operating conditions (see, for example, Patent Document 1).

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2003-56411

[0005] Since the conventional exhaust gas recirculation device is configured as described above, the EGR valve is simply attached to the exhaust gas recirculation passage, and between the valve seat of the EGR valve and the valve body. If foreign matter (for example, cutting powder or carbon particles) in the exhaust gas is swallowed, the exhaust gas leaks and causes problems such as rafiddle or engine failure.

[0006] As a method of solving the problem, (l) replacing the EGR valve, and (2) forcing the EGR valve to open and close separately from the normal opening and closing when starting the engine with idling ON, Has been proposed (see the same document). However, in the case of the method (1), the EGR valve can be used only by removing the foreign matter, but the EGR valve must be replaced and disposed, resulting in a new wasteful problem. It will be. [0007] In the case of method (2), since the EGR valve is forcibly opened and closed when the engine is started with the idling ON, the time until the complete explosion of the engine is short. There is a possibility that time until fully closed, fully opened, and fully closed again cannot be secured. On the other hand, if the time until the engine is started is delayed in order to secure time, it may take a long time to start the engine and the user may be dissatisfied. Furthermore, if the EGR valve is forcibly opened and closed while the engine is running even if no foreign object has been trapped, the foreign object is likely to be trapped between the EGR valve seat and the disc. A new problem arises in which the conditions are set in reverse.

[0008] The present invention has been made to solve the above-described problems, and ensures the time until the exhaust gas recirculation valve is fully opened and closed without needing to replace and dispose of the exhaust gas recirculation valve. The purpose is to provide a control device for the exhaust gas recirculation valve, which eliminates user dissatisfaction and does not easily set conditions that allow foreign objects to be swallowed.

Disclosure of the invention

[0009] An exhaust gas recirculation valve control device according to the present invention includes an exhaust gas recirculation passage that communicates an intake passage and an exhaust passage of an internal combustion engine to introduce a part of exhaust gas into the intake passage, and the exhaust gas return passage. An exhaust gas recirculation valve provided, an abnormality detection means for detecting an abnormality of the exhaust gas recirculation valve, and a valve forced opening / closing means for opening and closing the exhaust gas recirculation valve based on the abnormality detection of the abnormality detection means It is.

[0010] According to the present invention, since the existing exhaust gas recirculation valve can be used as it is by removing foreign substances in the stagnation state, it is not necessary to replace and dispose of the exhaust gas recirculation valve wastefully. There is an excellent effect. In addition, the time until the exhaust gas recirculation valve is fully opened and closed can be secured, and there is an effect that it is not easy to easily set conditions for foreign matter to be trapped.

Brief Description of Drawings

FIG. 1 is an overall configuration diagram schematically showing an embodiment of an exhaust gas recirculation valve control device according to the present invention.

[Fig. 2] EGR in the embodiment of the control device for the exhaust gas recirculation valve according to the present invention. It is a fragmentary sectional view showing a valve typically.

FIG. 3 is a flowchart showing Embodiment 1 of the exhaust gas recirculation valve control apparatus according to the present invention.

FIG. 4 is a flow chart showing Embodiment 2 of the control device for the exhaust gas recirculation valve according to the present invention.

FIG. 5 is a flowchart showing Embodiment 3 of the control device for the exhaust gas recirculation valve according to the present invention.

FIG. 6 is a flowchart showing Embodiment 4 of the control device for the exhaust gas recirculation valve according to the present invention.

FIG. 7 is a flowchart showing Embodiment 5 of the control device for the exhaust gas recirculation valve according to the present invention.

FIG. 8 is a flow chart showing Embodiment 6 of the exhaust gas recirculation valve control apparatus according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, in order to describe the present invention in more detail, the best mode for carrying out the invention will be described with reference to the accompanying drawings.

Embodiment 1.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 3, the control device for the exhaust gas recirculation valve in the first embodiment communicates the exhaust passage 10 and the exhaust passage 10 of the engine 1 that is an internal combustion engine of an automobile with each other. Controls the exhaust recirculation passage 20 that introduces a part (for example, 5-20%) into the intake passage 3, the stepper motor type EGR valve 30 that is installed in the exhaust recirculation passage 20, the engine 1, the EGR valve 30, and the like. And an electronic control unit 50.

[0013] The engine 1 is not particularly limited in power such as a three-cylinder, a four-cylinder, a six-cylinder, an in-line type, and a horizontally opposed type. As shown in FIG. 1, the engine 1 is provided with an igniter 2 such as an ignition coil and an igniter.

[0014] The intake passage 3 is made of, for example, a metal pipe that circulates outside air or air-fuel mixture (see the arrow in FIG. 1). As shown in FIG. 1, an air cleaner 4 that removes dust in the outside air is provided in the upstream portion. Connection Downstream of the air cleaner 4, a throttle valve 6 for adjusting the suction amount is rotatably supported, and an injector 5 is attached to each cylinder of the intake bear-hold 9. A bypass passage 7 that bypasses the throttle valve 6 is bent and connected to the intake passage 3, and an idle rotation speed control valve 8 is attached to the bypass passage 7.

A branched intake bear hold 9 is connected to the downstream portion of the intake passage 3, and the intake bear hold 9 allows the air-fuel mixture to flow into each cylinder of the engine 1. Thus, when the air-fuel mixture flows into each cylinder of the engine 1, it is burned by a spark plug that generates a spark and becomes exhaust gas after combustion.

[0016] The exhaust passage 10 also has, for example, a metal pipe force for flowing exhaust gas (see the arrow in FIG. 1). As shown in the figure, the upstream portion is connected to the engine 1, and the downstream portion is a three-dimensional catalyst or the like. A purifier 11 is connected, and the purifier 11 purifies the exhaust gas and releases it to the atmosphere.

The exhaust gas recirculation passage 20 is made of, for example, a bent metal pipe, and is connected to the intake passage 3 and the exhaust passage 10. The exhaust gas recirculation passage 20 is connected to the portion of the intake passage 3 downstream of the throttle valve 6 in the intake passage 3.

As shown in FIGS. 1 and 2, the EGR valve 30 includes a housing 31 attached to a part of the exhaust gas recirculation passage 20, a valve body 39 for opening and closing a valve seat 38 of the housing 31, and the valve It includes a stepper motor 43 that moves the body 39 up and down, and functions to lower the temperature of the combustion gas by controlling the recirculation amount of the exhaust gas flowing through the exhaust gas recirculation passage 20.

[0019] The nosing / housing 31 is basically formed in a substantially cylindrical shape, and the inside thereof is partitioned into two upper and lower spaces, and penetrates through the central portion of the partition plate 32 that partitions the upper and lower two spaces. A hole 33 is formed, and a cylindrical bush 34 is inserted into the through hole 33.

[0020] An output port 35 communicating with the intake passage 3 is perforated on the peripheral wall that defines the lower space of the housing 31, and the bottom of the lower space is formed as an opening at the input port 36 communicating with the exhaust passage 10. The output port 35 and the input port 36 are partitioned into a reflux passage 37. A planar substantially ring-shaped valve seat that exhibits a sealing function is fitted to the peripheral portion of the reflux passage 37, and this valve seat forms a valve seat 38. [0021] The valve body 39 is attached to and supported by the lower end portion of the valve shaft 40 penetrating the bush 34 so as to reciprocate. A spring holder 41 is attached to the upper end portion of the valve shaft 40. A spring 42 is interposed between the holder 41 and the housing 31 in a state of being inserted into the opening of the valve seat 38 to urge the valve body 39.

The stepper motor 43 is installed on the upper portion of the housing 31 to close the upper space, and is driven to rotate under the control of the control unit 50. The motor shaft 44 is connected to the drive shaft of the stepper motor 43, converts the rotational motion of the stepper motor 43 into a linear motion and transmits it to the valve shaft 40, and the opening force of the valve seat 38 also separates the valve body 39 downward. It works as follows.

[0023] As shown in FIG. 1, the control unit 50 includes a water temperature sensor that detects the cooling water temperature of the engine 1.

51 detection, engine 1 ignition device 2 operating state detection means, intake passage 3 internal pressure detection pressure sensor 52 detection, throttle valve 6 opening detection throttle opening sensor 53 detection, user Engine 1 and EGR valve 30 are controlled based on the start signal of idling ON.

The control unit 50 detects an abnormality of the EGR valve 30, specifically, an entrapping caused by a foreign object in the EGR valve 30 when the ECU reads the data of the various sensors described above. Based on the anomaly detection function and the anomaly detection of this anomaly detection function, the EGR valve 30 is forcibly opened / closed immediately and separately forcibly opened / closed. The forced valve open / close function is a function that forcibly opens the valve body 39 of the EGR valve 30 to remove foreign substances, then closes the valve body 39 of the EGR valve 30 and ends the tallying mode to remove foreign substances. is there.

[0025] In the above, when a large foreign matter in the exhaust gas is swallowed between the valve seat 38 and the valve body 39 of the EGR valve 30, and when the valve is closed, leakage of the exhaust gas increases and engine 1 is generated. As shown in FIG. 3, the ECU of the control unit 50 detects the engine 1 engine engine engine stalled by foreign objects from its rotational speed, etc. (step ST1), and forcibly controls the valve body 39 of the EGR valve 30. After opening the valve (step ST2) to remove foreign matter, the valve body 39 of the EGR valve 30 is closed (step ST3), and the cleaning mode to remove the foreign matter is completed, and it is possible to return to normal idle rotation. Become.

At this time, the EGR valve 30 and the control unit 50 detect that the engine 1 has an engine stall. Immediately shifts to a cleaning mode for removing foreign matter. In addition, the valve body 39 of the EGR valve 30 has a larger structural and structural maximum valve opening amount (the maximum number of steps for opening the valve body 39) than the normal control valve opening amount (for example, a small automobile) Etc.), the probability of removing foreign matter is improved by opening the valve with the maximum valve opening in terms of mechanism and structure.

[0027] As described above, according to the first embodiment, foreign matter is quickly removed, so that the EGR valve 30 that has already been used can be used as it is, and the EGR valve 30 itself can be replaced. It is possible to eliminate the waste of doing. When engine 1 is stalled, it immediately shifts to cleaning mode. The time from the occurrence of the engine stall until the user restarts and completes the explosion is longer than the time until the explosion is completed, so the time until cranking is increased. Sufficient on-off valves can be provided without dissatisfaction with the user.

[0028] Furthermore, since the EGR valve 30 opens and closes for the first time based on the detection of the abnormality, the EGR valve 30 does not open and close during the operation of the engine 1 even though there is no foreign object. . Therefore, foreign matter is easily trapped between the valve seat 38 and the valve body 39 of the EGR valve 30, and the conditions are not easily set.

[0029] Embodiment 2.

Next, FIG. 4 shows the second embodiment. In this case, the forced valve opening / closing function stores an abnormality in the memory of the control unit 50 and forcibly opens the valve body 39 of the EGR valve 30. Then, remove the foreign matter, and then close the valve body 39 of the EGR valve 30 to reset the memory that stores the abnormality based on the completion of the complete explosion of the engine 1!

[0030] In the second embodiment, large foreign substances in the exhaust gas are trapped between the valve seat 38 and the valve body 39 of the EGR valve 30, and the exhaust gas leakage increases when the valve is closed, causing the engine 1 to stall. When this occurs, the ECU of the control unit 50 detects the engine 1 engine engine stall due to foreign object penetration (step ST1), and an error occurs in the memory (not shown) provided in the control unit 50. (Enst) is memorized (step ST2), and the valve body 39 of the EGR valve 30 is forcibly opened at the maximum valve opening amount (step ST3) to drop the foreign matter.

[0031] When the valve body 39 of the EGR valve 30 is opened, the valve body 39 of the EGR valve 30 is closed (step ST4), the complete explosion of the engine 1 is completed (step ST5), and the memory storing the abnormality is stored. Force S reset (step ST6), the cleaning mode to remove foreign matter is completed, and normal control is restored. The other parts are substantially the same as those in the first embodiment, and the description thereof is omitted.

As described above, according to the second embodiment, it is possible to expect the same effect as the first embodiment, and it is obvious that the cleaning mode for removing foreign matter can be continuously performed. It is easy. Explaining this point, it suffices if the foreign matter can be removed in a single cleaning mode after the engine 1 is stalled, but if it cannot be removed, the engine 1 cannot be restarted. In addition, the cleaning mode cannot be continuously performed when it is not possible to determine that the engine stall is after the start mode of the engine 1 is completed.

[0033] However, according to the second embodiment, the valve body 39 of the EGR valve 30 is not immediately opened, but the valve is opened after the abnormality is stored in the memory of the control unit 50. Even in the event of failure, the cleaning mode, that is, the opening and closing of the valve body 39 of the EGR valve 30 can be repeated by turning the key ON, the engine OFF or the key OFF, greatly improving the possibility of removing foreign substances in the cleaning mode. Can do.

[0034] In the second embodiment, the memory storing the abnormality is reset based on the completion of the complete explosion of the engine 1, but the memory is not limited to this but the completion signal of the start mode of the engine 1 is not limited to this. May be reset.

[0035] Embodiment 3.

FIG. 5 shows the third embodiment. The forced valve opening / closing function in this case is such that when the engine 1 is restarted during the tally mode and an initialization signal is output, the valve body 39 of the EGR valve 30 is shown. Priority is given to initialization over opening and closing

[0036] In the third embodiment, large foreign substances in the exhaust gas are trapped between the valve seat 38 and the valve body 39 of the EGR valve 30, and the exhaust gas leakage increases when the valve is closed. When this occurs, the control unit 50 detects the engine 1 engine stall due to foreign object penetration (step ST1) and the valve body 39 of the EGR valve 30 is forced to reach the maximum valve opening amount. Open the valve (step ST2) to remove foreign matter.

[0037] After the valve 39 was opened, the engine 1 was restarted and an initialization signal was output. In this case (step ST3), the initialization operation is prioritized over the closing of the valve body 39 of the EGR valve 30 (step ST4), and when the initialization signal is not output, the valve body 39 is fully opened. The valve body 39 of the EGR valve 30 is closed (step ST6) on condition that the maximum number of steps has been reached (step ST5).

[0038] After the valve body 39 is closed in this way, when the engine 1 is restarted and the initialization signal is output (step ST7), the initialization operation is prioritized (step ST4) and the initialization signal is output. If not, the cleaning mode is terminated on condition that the valve 39 has opened 0 steps (step ST8). Other parts are substantially the same as those in the second embodiment, and the description thereof is omitted.

As described above, according to the third embodiment, the same effect as that of the second embodiment can be expected, and the initialization operation is prioritized over the opening and closing of the valve body 39 of the EGR valve 30. Therefore, it is possible to prevent and suppress the engine stall again. Explaining this point, if the EGR valve 30 is opened and closed several times during the cleaning mode, the user may restart the engine 1. In this case, even if the foreign matter can be removed in the cleaning mode, the engine 1 may be re-established if the cleaning mode is continued when the engine 1 is started.

[0040] According to the third embodiment, the initializing operation is given priority over the opening and closing of the valve body 39 of the EGR valve 30, and the EGR valve 30 is closed. Even if the user restarts the engine 1, there is no adverse effect associated with the opening of the EGR valve 30.

[0041] Embodiment 4.

FIG. 6 shows the fourth embodiment. In this case, the abnormality detection function is an abnormality of the EGR valve 30, specifically, the idle rotation number less than the specified value due to the entrapment of foreign matter in the EGR valve 30. Based on the detection of the idling speed below the specified value, the forced valve open / close function stores the abnormality in the memory of the control unit 50 and implements the taring mode when the operating conditions of the cleaning mode are satisfied. However, the memory that stores the abnormality is reset on condition that the idling speed exceeds the specified value.

[0042] In the fourth embodiment, between the valve seat 38 of the EGR valve 30 and the valve body 39, If a small foreign object is trapped and the engine 1 idle speed becomes unstable below the specified value, the ECU of the control unit 50 detects the idle speed below the specified value due to the foreign object swallowing ( Step ST1), and when the abnormality is stored in the memory of the control unit 50 (Step ST2) and the operating conditions of the cleaning mode of the EGR valve 30 are satisfied (Step ST 3), the cleaning mode of the EGR valve 30 That is, the valve body 39 of the EGR valve 30 opens and closes (step ST4).

[0043] At this time, if the foreign matter to be swallowed is small, the engine 1 will not be stalled, but will become unstable when the idle speed is below the specified value, so the idle speed will be below the specified value. If this is dealt with, it will be possible to effectively and appropriately deal with small foreign object stagnation and EGR valve 30 malfunctions. In addition, foreign object stagnation is indirectly detected by the idle speed below the specified value of engine 1, so foreign object stagnation can be performed regardless of the presence or absence of devices or methods that directly detect foreign object stagnation. Can be detected easily and reliably.

[0044] However, in this case, even if an abnormality is detected, the valve cannot be forcibly opened when the engine 1 is idling. Therefore, the abnormality is stored in the memory of the control unit 50 and the Shifts to the cleaning mode of the EGR valve 30 when the operating conditions of the first mode are satisfied (Note that even if the idling is unstable, the engine 1 is not at the level where it will stall, so it is possible to run and immediately after detecting an abnormality. It is possible to drive without entering the cleaning mode.

[0045] The operating condition of the cleaning mode of the EGR valve 30 is when the vehicle is in a steady running state (changes in engine 1 speed and charging efficiency are less than specified values), or when the vehicle is decelerating at speeds and speeds greater than the specified values. (Idle switch ON).

[0046] When the cleaning mode of the EGR valve 30 is thus completed and the engine 1 is in the idling state (step ST5) and the rotation speed exceeds the specified value (step ST6), the memory storing the abnormality is stored. Reset (step ST7). Other parts are substantially the same as those in the third embodiment, and the description thereof is omitted.

[0047] As described above, according to the fourth embodiment, the same effects as those of the third embodiment can be expected, and even if the force does not reach the engine stall, the EGR valve 30 is entrapped. To deal with Obviously, it is possible to reliably detect the entrapment of foreign matter.

[0048] Embodiment 5.

FIG. 7 shows the fifth embodiment. In this case, the forced valve opening / closing function has a fixed time after the abnormality is stored in the memory when the operating condition of the cleaning mode of the EGR valve 30 is not satisfied. If a certain period of time has elapsed and the valve body 39 of the EGR valve 30 is at least partially operated (for example, when high speed driving is possible on a highway, etc.) Therefore, the valve is opened larger than in normal control (step ST9).

[0049] The valve element 39 of the EGR valve 30 is opened with the maximum opening amount (maximum number of steps) in terms of structure and structure, thereby improving the probability of removing foreign matter. Other parts are substantially the same as those in the fourth embodiment, and the description thereof is omitted.

It is obvious that the same effect as in the fourth embodiment can be expected in the fifth embodiment.

[0050] Embodiment 6.

FIG. 8 shows the sixth embodiment. In this case, the abnormality detection function is the abnormality of the EGR valve 30, specifically, the calculated negative pressure of the intake hold 9 (P—IMAP) and the measured value ( P− MAP) is detected more than the specified value (A Pt), and the valve forced open / close function is greater than the specified value (A Pt) between the calculated value (P-IMAP) and the measured value (P— MAP). Based on the difference detection, the abnormality is stored in the memory of the control unit 50 and the cleaning mode is executed on the condition that the operating condition of the cleaning mode is satisfied, and the negative pressure of the intake hold 9 is calculated when the engine 1 is idling. The memory storing the abnormality is reset on condition that the difference between the value (P—IMAP) and the measured value (P—MAP) is less than the specified value (A Pt).

[0051] In the sixth embodiment, foreign matter in the exhaust gas is trapped between the valve seat 38 and the valve body 39 of the EGR valve 30, and the calculated negative pressure of the intake bear hold 9 (P—IMAP ) And the measured value (P—MAP) exceeds the specified value (A Pt), the ECU of the control unit 50 detects a difference greater than the specified value of the negative pressure that accompanies foreign object (step ST1 If the abnormality is stored in the memory of the control unit 50 (step ST2) and the operation conditions for the cleaning mode of the EGR valve 30 are satisfied (step ST3), the cleaning mode of the EGR valve 30 is That is, the valve body 39 of the EGR valve 30 is opened and closed (step ST4).

At this time, the calculated value of the negative pressure is estimated by the engine speed, the throttle valve 6 and the like, and the actual measured value of the negative pressure is measured by a MAP sensor (Manifold Absolute Pressure sensor) which is a pressure sensor.

[0053] Thus, the cleaning mode of the EGR valve 30 is finished, and the calculated value (P—IMAP) and measured value (P—MAP) of the negative pressure of the intake bear hold 9 when the engine 1 is idling (step ST5). If the difference is less than the specified value (APt) (step ST6), the memory storing the abnormality is reset (step ST7). Other parts are substantially the same as those in the above embodiment, and thus the description thereof is omitted.

As described above, according to the sixth embodiment, the same effect as in the fifth embodiment can be expected, and the bending force is calculated from the calculated value and the measured value of the negative pressure of the intake bear-hold 9. If the difference between the values exceeds a specified value, it is possible to detect an abnormality caused by the foreign object in the EGR valve 30.

[0055] Describing this point, the calculated value of the negative pressure and the actually measured value are in a proportional relationship although a difference occurs. When the EGR valve 30 is opened, the measured value fluctuates to the atmosphere side.For this reason, foreign matter in the exhaust gas is trapped between the valve seat 38 and the valve body 39 of the EGR valve 30, and the valve leakage increases. The difference between the calculated negative pressure value and the actual measurement value is larger than that in the normal state. Therefore, if the difference between the calculated value of the negative pressure of the intake bear-hold 9 and the actual measured value is equal to or greater than the specified value, it is possible to estimate an abnormality caused by the foreign object in the EGR valve 30.

In each of the above embodiments, the force indicating the engine 1 of the automobile as the internal combustion engine is not limited to this. For example, an engine 1 such as a water bike or a snow vehicle may be used. Also, the EGR valve 30 can be opened and closed multiple times, such as 2-5 times, 10 times, etc., depending on the need for foreign matter removal.

Industrial applicability

As described above, the exhaust gas recirculation valve control apparatus according to the present invention includes an exhaust gas recirculation passage that communicates an intake passage and an exhaust passage of an internal combustion engine and introduces a part of the exhaust gas into the intake passage. An exhaust gas recirculation valve provided in the exhaust gas recirculation passage, an abnormality detection means for detecting an abnormality of the exhaust gas recirculation valve, and a valve forced opening / closing means for opening and closing the exhaust gas recirculation valve based on an abnormality detection of the abnormality detection means; Exhaust gas recirculation with Since it is a control device for a ring valve, it is suitable for use in a control device for an exhaust gas recirculation valve of an automobile having an internal combustion engine, a water bike or a snow vehicle.

Claims

The scope of the claims

[1] An exhaust gas recirculation passage that connects an intake passage and an exhaust passage of an internal combustion engine to introduce a part of exhaust gas into the intake passage, an exhaust gas recirculation valve provided in the exhaust gas recirculation passage, and the exhaust gas recirculation An exhaust gas recirculation valve control device comprising: an abnormality detection means for detecting an abnormality of the valve; and a valve forced opening / closing means for opening and closing the exhaust gas recirculation valve based on the abnormality detection of the abnormality detection means.

[2] The exhaust gas recirculation valve control device according to [1], wherein the abnormality detection means detects an abnormality caused by a foreign matter trapped in the exhaust gas recirculation valve when the internal combustion engine stops rotating.

[3] The exhaust gas recirculation valve control apparatus according to [1], wherein the valve forced opening / closing means immediately opens and closes the exhaust gas recirculation valve based on the abnormality detection.

[4] The exhaust gas recirculation valve control device according to [1], wherein the valve forced opening / closing means opens the exhaust gas recirculation valve with a maximum valve opening amount of the mechanism.

[5] Based on the abnormality detection, the forced valve opening / closing means memorizes the abnormality in the memory and opens / closes the exhaust gas recirculation valve. When the internal combustion engine completes the explosion or the start is completed, the memory storing the abnormality is stored. The exhaust gas recirculation valve control device according to claim 1, wherein the exhaust gas recirculation valve is reset.

[6] The valve forced opening / closing means gives priority to the initialization operation over the opening / closing of the exhaust gas recirculation valve when the internal combustion engine is restarted after an abnormality is detected and an initialization signal is output. Control device for exhaust gas recirculation valve.

[7] The exhaust gas recirculation valve control device according to [1], wherein the abnormality detection means detects an abnormality caused by a foreign object trapped in the exhaust gas recirculation valve based on an idle speed equal to or less than a specified value of the internal combustion engine.

8. The exhaust gas recirculation valve control device according to claim 7, wherein the valve forced opening / closing means opens the exhaust gas recirculation valve with a maximum valve opening amount of the mechanism.

[9] Based on the detection of the idle speed below the specified value, the Noreb forced opening / closing means stores an abnormality in the memory, and if the operating condition of the exhaust gas recirculation valve is satisfied, the exhaust gas recirculation valve is turned on. 8. The exhaust gas recirculation valve control device according to claim 7, wherein when the idling speed of the internal combustion engine exceeds a specified value, the memory storing the abnormality is reset.

[10] Valve forced opening / closing means is used when the operating conditions of the exhaust gas recirculation valve are not satisfied. Determines whether or not a certain amount of time has passed since the abnormality was stored in the memory, and if a certain amount of time has elapsed, the exhaust gas recirculation valve is normally controlled in at least some operating regions. 8. The exhaust gas recirculation valve control device according to claim 7, wherein the exhaust gas recirculation valve is opened with a maximum valve opening amount larger than that in the above case.

[11] Abnormality detection means detects foreign matter in the exhaust gas recirculation valve when the difference between the calculated value of the negative pressure of the intake hold that connects the internal combustion engine and the intake passage exceeds the specified value. The control device for an exhaust gas recirculation valve according to claim 1, wherein an abnormality due to a trap is detected.

[12] The Norev forced opening / closing means memorizes the abnormality in the memory based on the detection of the difference between the calculated value of the negative pressure of the intake hold and the measured value, and the operating condition of the exhaust gas recirculation valve is If satisfied, the exhaust gas recirculation valve is opened and closed.If the difference between the calculated value of the negative pressure of the intake manifold and the measured value is less than the specified value when the internal combustion engine is idling, 12. The exhaust gas recirculation valve control device according to claim 11, wherein the memory storing the reset is reset.