JP2009299591A - Egr control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To minimize pressure loss of intake air generated in introduction of EGR gas between a nozzle of a venturi device and a diffuser in an EGR control device for an internal combustion device. <P>SOLUTION: The venturi device 19 disposed in an intake passage 12 of the internal combustion device is provided with the nozzle 26 arranged on the upstream side and having a passage area reduced as going along a flow direction of the intake air, the diffuser 27 arranged on the downstream side and having a passage area increased as going along the flow direction of the intake air, and a slit 28 formed between the nozzle 26 and the diffuser 27 and communicated with an EGR passage 21. An inlet passage area of the diffuser 27 is controlled to be larger than an outlet passage area of the nozzle 26 for the value in accordance with an introduction amount of the EGR gas, and a step G of the slit 28 in a size in accordance with the amount of the EGR gas introduced from the EGR passage 21 to the intake passage 12 is formed, and thereby, the pressure loss can be minimized by reducing the turbulent flow generated in the intake air flowing through the intake passage 12 while smoothly introducing the EGR gas into the intake passage 12. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a venturi device provided in an intake passage of an internal combustion engine, an EGR passage that recirculates EGR gas from the exhaust passage of the internal combustion engine to the venturi device, and an EGR control means that controls the amount of EGR that flows through the EGR passage. And an EGR control device for an internal combustion engine.

  A venturi portion 2 is formed in the middle of the intake pipe 1, an annular chamber 3 is provided on the outer periphery of the throat portion of the venturi portion 2, and the reduced diameter portion is formed by an annular slit 6 that communicates the inside of the annular chamber 3 with the inside of the intake pipe 1. Patent Document 1 below discloses that the EGR gas is introduced into the intake pipe 1 from the annular chamber 3 through the annular slit 6.

Further, a venturi 9 is provided at a connection portion where the transfer channel 4 for recirculating EGR gas to the intake channel 2 is connected, and the drive shaft 11 drives the wall portion 10 of the venturi 9 so as to protrude and retract with respect to the recess 12. A technique for changing the passage area of the venturi 9 in the intake channel 2 is known from the following Patent Document 2.
JP 2007-92592 A Special Table 2003-534487

  By the way, what was described in the said patent document 1 is downstream rather than the minimum internal diameter part (downstream end of the diameter reduction part 7) of the venturi part 2 by providing the level | step difference G between the diameter reduction part 7 and the diameter expansion part 8. FIG. Although the suction action of the EGR gas is enhanced by the negative pressure generated on the side (the enlarged diameter part 8 side), the venturi part 2 is integrally formed by casting, and the height of the step G is related to the amount of EGR gas introduced. Is constant.

  Moreover, although what was described in the said patent document 2 drives the wall part 10 which integrally has a reduced diameter part and an enlarged diameter part with the drive shaft 11, in this structure, a nozzle exit, a diffuser inlet, It is impossible to adjust the step between the two.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to minimize the pressure loss of intake air generated when EGR gas is introduced between a nozzle and a diffuser of an venturi device in an EGR control device of an internal combustion engine. And

  To achieve the above object, according to the first aspect of the present invention, a venturi device provided in an intake passage of an internal combustion engine, and an EGR that recirculates EGR gas from the exhaust passage of the internal combustion engine to the venturi device. In an EGR control device for an internal combustion engine comprising a passage and an EGR control means for controlling the amount of EGR flowing through the EGR passage, the venturi device is disposed upstream of the intake passage when EGR is introduced, and A nozzle whose passage area decreases along the flow direction, a diffuser disposed downstream of the nozzle in the intake passage and whose passage area increases along the flow direction of intake air, a downstream end of the nozzle and the diffuser A slit that is formed between the upstream ends of the diffuser and communicates with the EGR passage, and a diffuser that changes the inlet passage area of the diffuser An inlet passage area variable mechanism, wherein the diffuser inlet passage area variable mechanism is configured to make the inlet passage area of the diffuser larger than the outlet passage area of the nozzle by a value corresponding to the amount of EGR gas introduced. An EGR control device for an internal combustion engine is proposed.

  According to the second aspect of the present invention, in addition to the configuration of the first aspect, an EGR control device for an internal combustion engine comprising a nozzle outlet passage area variable mechanism that changes an outlet passage area of the nozzle. Is proposed.

  According to a third aspect of the present invention, in addition to the configuration of the first aspect, the intake passage has a rectangular cross section at a portion where the venturi device is provided, and the diffuser is disposed on the downstream side thereof. An end portion includes a diffuser flap pivotally supported on the wall surface of the intake passage, and when the EGR gas is introduced, the diffuser inlet passage area variable mechanism moves the upstream end portion of the diffuser flap from the wall surface of the nozzle. An EGR control device for an internal combustion engine, wherein the downstream end of the inclined surface inclined in the separating direction is swung to a position close to the wall surface of the intake passage by a value corresponding to the amount of EGR gas introduced. Is proposed.

  According to the invention described in claim 4, in addition to the configuration of claim 3, the nozzle includes a nozzle flap whose upstream end is pivotally supported on the wall surface of the intake passage, and the nozzle flap. A variable nozzle outlet passage area variable mechanism, and when the EGR gas is not introduced, the diffuser inlet passage area variable mechanism causes the diffuser flap to follow the wall surface of the intake passage and the nozzle outlet passage area variable mechanism. An EGR control device for an internal combustion engine is proposed, in which the slit is extinguished by moving the nozzle flap along the wall surface of the intake passage.

  According to the fifth aspect of the present invention, in addition to the configuration of the third aspect, the nozzle includes a nozzle flap whose upstream end is pivotally supported by the wall surface of the intake passage, and the nozzle flap. A nozzle outlet passage area variable mechanism that swings, and the EGR passage opens on the wall surface of the intake passage between the upstream end and the downstream end of the nozzle flap, and when EGR gas is not introduced The EGR control device for an internal combustion engine is proposed in which the nozzle outlet passage area variable mechanism closes the EGR passage opened in the wall surface by causing the nozzle flap to follow the wall surface of the intake passage. The

  The EGR control valve 23 of the embodiment corresponds to the EGR control means of the present invention.

  According to the configuration of the first aspect, the venturi device provided in the intake passage of the internal combustion engine includes the nozzle disposed on the upstream side and reducing the passage area along the flow direction of the intake air when the EGR is introduced, and the downstream side And a slit that is formed between the nozzle and the diffuser and communicates with the EGR passage, and the diffuser inlet passage area variable mechanism is used to change the inlet of the diffuser. Since the passage area is changed to be larger than the nozzle outlet passage area by a value corresponding to the amount of EGR gas introduced, a slit step corresponding to the amount of EGR gas introduced from the EGR passage into the intake passage is formed. It is possible to minimize the pressure loss by reducing the turbulence generated in the intake air flowing through the intake passage while smoothly introducing EGR gas into the intake passage. It can be suppressed to.

  According to the second aspect of the invention, since the nozzle outlet passage area is changed by the nozzle outlet passage area variable mechanism, the restriction of the venturi device can be reduced by combining with the change of the inlet passage area of the diffuser by the diffuser inlet passage area variable mechanism. It is possible to arbitrarily change both the size of the nozzle and the level difference of the slit between the nozzle and the diffuser, and the disturbance of the intake air in the venturi device can be minimized while efficiently introducing the EGR gas.

  According to the configuration of claim 3, the diffuser of the venturi device includes a diffuser flap whose downstream end is pivotally supported on the wall surface of the intake passage having a rectangular cross section, and the area of the diffuser inlet passage when the EGR gas is introduced A variable mechanism swings the upstream end of the diffuser flap relative to the downstream end of the inclined surface of the nozzle to a position close to the wall of the intake passage by a value corresponding to the amount of EGR gas introduced. With the structure, it is possible to arbitrarily control the step of the slit between the nozzle and the diffuser, and to more effectively suppress the turbulence of the intake air accompanying the introduction of EGR gas.

  According to the fourth aspect of the present invention, the nozzle of the venturi device includes the nozzle flap whose upstream end is pivotally supported by the wall surface of the intake passage, and the nozzle outlet passage area variable mechanism that swings the nozzle flap. Therefore, when EGR gas is not introduced, the diffuser flap along the wall surface of the intake passage with the diffuser inlet passage area variable mechanism and the nozzle flap along the wall surface of the intake passage with the nozzle outlet passage area variable mechanism The slit between the diffusers can be eliminated. As a result, the nozzle and the diffuser do not protrude into the intake passage, and the slit does not open between the nozzle and the diffuser. Therefore, the pressure loss can be reduced by minimizing the flow resistance of the intake air.

  According to the fifth aspect of the present invention, the nozzle of the venturi device includes the nozzle flap whose upstream end is pivotally supported by the wall surface of the intake passage, and the nozzle outlet passage area variable mechanism that swings the nozzle flap. Therefore, the nozzle outlet passage area can be arbitrarily changed by swinging the nozzle flap by the nozzle outlet passage area variable mechanism. Further, when the EGR gas is not introduced, the EGR passage that opens on the wall surface between the upstream end portion and the downstream end portion of the nozzle flap is closed by aligning the nozzle flap along the wall surface of the intake passage, so that the EGR passage Even when the EGR control means is not provided, the supply of EGR gas can be stopped. In addition, when the EGR gas is introduced and the nozzle flap is swung away from the wall surface of the intake passage, the EGR passage opening in the wall surface is located upstream from the downstream end portion of the nozzle flap, and is thus introduced from the EGR passage. The generated EGR gas can be guided in the flow direction of the intake air along the back surface of the nozzle flap, and smoothly merged with the intake air to minimize the occurrence of pressure loss.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 7 show a first embodiment of the present invention. FIG. 1 is an overall configuration diagram of an EGR control device for an internal combustion engine, and FIG. 2 is a longitudinal sectional view of a venturi device (when EGR gas is not introduced). 3 is a sectional view taken along line 3-3 in FIG. 2, FIG. 4 is a longitudinal sectional view of the venturi device (when EGR gas is introduced), FIG. 5 is a sectional view taken along line 5-5 in FIG. FIG. 7 and FIG. 7 are graphs showing the pressure loss of the venturi device.

  As shown in FIG. 1, the internal combustion engine E using hydrogen as a fuel includes an intake passage 12 connected to the intake ports 11, and an exhaust passage 14 connected to the exhaust ports 13. The turbocharger 15 is formed by coaxially connecting a turbine 16 facing the exhaust passage 14 and a compressor 17 facing the intake passage 12, and transmits the rotation of the turbine 16 driven by the exhaust gas flowing through the exhaust passage 14 to the compressor 17. The intake air is compressed by the rotating compressor 17 to perform supercharging.

  An intercooler 18 is provided in the intake passage 12 that connects the compressor 17 of the turbocharger 15 and the intake ports 11 of the internal combustion engine E to cool intake air that has been compressed by the compressor 17 and has risen in temperature. A venturi device 19 is provided in the intake passage 12 upstream of the compressor 17, and the exhaust passage 14 between the turbine 16 and the exhaust gas purification catalyst 20 downstream thereof is connected to the venturi device 19 via the EGR passage 21. Is done. In the EGR passage 21, an EGR cooler 22 that cools the EGR gas is disposed on the upstream side, and an EGR control valve 23 that controls the flow rate of the EGR gas is disposed on the downstream side.

  The venturi device 19 includes a nozzle 26 that is tapered to throttle the intake air supplied from the upstream intake passage 12, and a diffuser 27 that extends from the downstream end of the nozzle 26. The downstream end of the EGR passage 21 opens in the slits 28 between the diffuser 27.

  As shown in FIG. 2 to FIG. 6, at least a portion where the venturi device 19 is provided in the intake passage 12 has a rectangular cross section. The nozzle 26 includes a pair of upper and lower nozzle flaps 32U and 32L whose ends on the upstream side in the flow direction of the intake air are pivotally supported by upper and lower wall surfaces 12a and 12b of the intake passage 12 by pivots 31 and 31, respectively. These nozzle flaps 32U and 32L are driven to swing by a nozzle outlet passage area variable mechanism 33 constituted by an electric motor or the like connected to the support shafts 31 and 31.

  In the portion where the EGR passage 21 is opened in the venturi device 19, upper and lower chambers 34U, 34L are recessed in the upper and lower wall surfaces 12a, 12b of the intake passage 12, and both chambers 34U, 34L are connected to the communication passage 35 (see FIG. 3 and FIG. 3). Communicate with each other via FIG. When the nozzle flaps 32U and 32L are swung to the outermost side and are along the wall surfaces 12a and 12b of the intake passage 12 (see FIG. 2), the chambers 34U and 34L are closed by the nozzle flaps 32U and 32L. And communication with the intake passage 12 is also blocked. When the downstream end portions of the nozzle flaps 32U and 32L are swung so as to approach each other (see FIG. 4), the passage area of the nozzle 26 changes so that the downstream side is narrowed.

  The downstream end portions of the pair of diffuser flaps 36U and 36L are pivotally supported by the support shafts 37 and 37 on the upper and lower wall surfaces 12a and 12b of the intake passage 12 on the downstream side of the pair of nozzle flaps 32U and 32L. These diffuser flaps 36U and 36L are driven to swing by a diffuser inlet passage area variable mechanism 38 constituted by an electric motor or the like connected to the support shafts 37 and 37.

  When the diffuser flaps 36U and 36L are swung to the outermost side and along the wall surfaces 12a and 12b of the intake passage 12 (see FIG. 2), downstream of the nozzle flaps 32U and 32L along the wall surfaces 12a and 12b of the intake passage 12 The end portions on the side and the end portions on the upstream side of the diffuser flaps 36U, 36L are in close contact with each other, and the slits 28, 28 disappear. When the upstream end portions of the diffuser flaps 36U and 36L are swung so as to approach each other (see FIG. 4), the passage area of the diffuser 27 changes so that the downstream side is expanded.

  Next, the operation of the first embodiment of the present invention having the above configuration will be described.

  The internal combustion engine E is a type that does not include a throttle valve, and the output is controlled by controlling the fuel injection amount to the intake system.

  Exhaust gas discharged from the exhaust ports 13 of the internal combustion engine E to the exhaust passage 14 is driven in the exhaust gas purification catalyst 20 after being driven by the turbine 16 of the turbocharger 15 and discharged in a purified state. The intake air compressed by the compressor 17 driven by the turbine 16 of the turbocharger 15 is cooled by the intercooler 18 and then sucked into the internal combustion engine E from the intake ports 11 to be used for fuel combustion. The EGR gas introduced into the EGR passage 21 branched from the exhaust passage 14 downstream of the turbine 16 of the turbocharger 15 is cooled by the EGR cooler 22, then the flow rate is controlled by the EGR control valve 23, and is generated in the venturi device 19. By returning to the intake passage 12 with a negative pressure, it contributes to the reduction of NOx in the exhaust.

  When EGR gas is not introduced into the intake passage 12, the nozzle flaps 32U and 32L are swung to positions along the wall surfaces 12a and 12b of the intake passage 12 by the nozzle outlet passage area variable mechanism 33 and the diffuser inlet passage The diffuser flaps 36U and 36L are swung to positions along the wall surfaces 12a and 12b of the intake passage 12 by the area variable mechanism 38 (see FIGS. 2 and 3). As a result, the chambers 34U and 34L are closed by the nozzle flaps 32U and 32L, and consequently the EGR passage 21 is also closed. Therefore, the EGR gas can be introduced into the intake passage 12 without closing the EGR control valve 23. Can be stopped. At the same time, the slits 28 and 28 between the nozzle flaps 32U and 32L and the diffuser flaps 36U and 36L disappear, and the inner surface of the intake passage 12 in the vicinity of the venturi device 19 has a smooth shape with no protrusions or recesses. Smooth distribution is possible and the occurrence of pressure loss can be minimized.

  When introducing EGR gas from the exhaust passage 14 to the intake passage 12 via the EGR passage 21, the nozzle flaps 32U and 32L are swung in directions approaching each other by the nozzle outlet passage area variable mechanism 33. The passage area of the diffuser 27 is reduced by reducing the passage area of the nozzle 26 along the flow direction of the intake air and swinging the diffuser flaps 36U and 36L toward each other by the diffuser inlet passage area variable mechanism 38. (See FIGS. 4 and 5).

  At this time, by increasing the inlet passage area at the upstream end of the diffuser 27 with respect to the outlet passage area at the downstream end of the nozzle 26 by a value corresponding to the amount of EGR gas introduced, a predetermined level difference is obtained. Slits 28, 28 having G (see FIG. 4) are formed between the nozzle 26 and the diffuser 27. The amount of fluid flowing through the diffuser 27 is increased by the amount of EGR gas introduced from the slits 28, 28 with respect to the amount of fluid flowing through the nozzle 26, but the inlet passage area at the upstream end of the diffuser 27 is reduced. By making the outlet passage area at the downstream end of the nozzle 26 larger by a value corresponding to the amount of EGR gas introduced, the generation of turbulent flow in the intake passage 12 near the slits 28 and 28 into which the EGR gas flows is prevented. Thus, it is possible to smoothly introduce the EGR gas into the intake passage 12 while reducing the pressure loss in the venturi device 19.

  Moreover, the positions of the chambers 34U and 34L communicating with the EGR passage 21 are on the upstream side in the intake air flow direction from the slits 28 and 28 opened between the nozzle flaps 32U and 32L and the diffuser flaps 36U and 36L. , 34L is guided along the back surface of the nozzle flaps 32U, 32L substantially parallel to the flow direction of the intake air, and more smoothly merges with the intake air flowing through the intake passage 12 through the slits 28, 28. Can do.

  As is apparent from FIG. 7, when EGR gas is not introduced, the inlet passage of the diffuser 27 is larger than the outlet passage area of the nozzle 26 when the outlet passage area of the nozzle 26 and the inlet passage area of the diffuser 27 are equal. It can be seen that the pressure loss in the venturi device 19 is smaller than when the area is increased. The reason is that when the EGR gas is not introduced, the flow rate of the intake air in the nozzle 26 and the flow rate of the intake air in the diffuser 27 are equal. Therefore, the turbulence of the intake air is increased by increasing the inlet passage area with respect to the outlet passage area. Because it does.

  On the other hand, when the EGR gas is introduced, the outlet passage area of the nozzle 26 and the inlet passage area of the diffuser 27 are equal to each other than the case where the inlet passage area of the diffuser 27 is larger than the outlet passage area of the nozzle 26. It can also be seen that the pressure loss in the venturi device 19 has increased. The reason is that when the EGR gas is introduced, the flow rate of the intake air in the diffuser 27 is increased by the amount of the introduced EGR gas rather than the flow rate of the intake air in the nozzle 26. This is because the disturbance of the intake air increases.

  Thus, according to the present embodiment, it is possible to achieve both a reduction in pressure loss when EGR gas is introduced and a reduction in pressure loss when EGR gas is not introduced.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  The venturi device 19 of the first embodiment includes two nozzle flaps 32U and 32L and the diffuser flaps 36U and 36L. The venturi device 19 of the second embodiment includes one nozzle each. A flap 32 and a diffuser flap 36 are provided.

  According to this embodiment, not only can the number of nozzle flaps 32 and diffuser flaps 36 be reduced to reduce the number of parts and the cost, but also only one chamber 34 has to be provided on the side where the EGR passage 21 is opened. The communication path 35 (see FIGS. 3 and 5) required when the two chambers 34U and 34L are provided is not necessary, and the structure can be further simplified.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, the internal combustion engine E that uses hydrogen as fuel is illustrated, but the present invention applies to an internal combustion engine E that uses gasoline or light oil as fuel, and also to an internal combustion engine E that does not have the turbocharger 15. Can also be applied.

  In the embodiment, both the nozzle flaps 32, 32U, 32L and the diffuser flaps 36, 36U, 36L are swingable. However, the nozzle flaps 32, 32U, 32L are fixed, and only the diffuser flaps 36, 36U, 36L are provided. It may be swingable.

  In the embodiment, the intake passage 12 has a rectangular cross section in the vicinity of the venturi device 19, and the nozzle flaps 32, 32U, 32L and the diffuser flaps 36, 36U, 36L have a flat plate shape. However, the intake passage 12 has a circular cross section. The nozzle flaps 32, 32U, 32L and the diffuser flaps 36, 36U, 36L may be configured so as to be able to expand and contract in a cone shape.

  The EGR control means of the present invention is not limited to the EGR control valve 23 of the embodiment, and the exhaust pressure and intake pressure are controlled by the exhaust pressure control valve provided in the exhaust pipe, the nozzle outlet passage area variable mechanism 33 of the present invention, or the like. And the one that controls the EGR flow rate by controlling the differential pressure.

  In the embodiment, when the EGR gas is not introduced, the downstream end of the nozzle flaps 32, 32U, 32L and the upstream end of the diffuser flaps 36, 36U, 36L are brought into contact with each other to eliminate the slit 28. The slits 28 may be eliminated by partially overlapping the downstream ends of 32U and 32L and the upstream ends of the diffuser flaps 36, 36U and 36L.

1 is an overall configuration diagram of an EGR control device for an internal combustion engine according to a first embodiment. Vertical section of venturi device (when EGR gas is not introduced) 3-3 sectional view of FIG. Longitudinal section of venturi device (when EGR gas is introduced) Sectional view along line 5-5 in FIG. Perspective view of venturi device Graph showing pressure loss of venturi device Longitudinal sectional view of the venturi device according to the second embodiment (when EGR gas is introduced)

Explanation of symbols

12 Intake passage 12a Wall surface 12b Wall surface 14 Exhaust passage 19 Venturi device 21 EGR passage 23 EGR control valve (EGR control means)
26 Nozzle 27 Diffuser 28 Slit 32 Nozzle flap 32U Nozzle flap 32L Nozzle flap 33 Nozzle outlet passage area variable mechanism 36 Diffuser flap 36U Diffuser flap 36L Diffuser flap 38 Diffuser inlet passage area variable mechanism E Internal combustion engine

Claims (5)

A venturi device (19) provided in the intake passage (12) of the internal combustion engine (E);
An EGR passage (21) for recirculating EGR gas from the exhaust passage (14) of the internal combustion engine (E) to the venturi device (19);
In an EGR control device for an internal combustion engine, comprising an EGR control means (23) for controlling an EGR amount flowing in the EGR passage (21),
The venturi device (19) is used when EGR is introduced.
A nozzle (26) disposed upstream of the intake passage (12) to reduce the passage area along the flow direction of intake air;
A diffuser (27) disposed downstream of the nozzle (26) of the intake passage (12) and having an increased passage area along the direction of intake air flow;
A slit (28) formed between the downstream end of the nozzle (26) and the upstream end of the diffuser (27) and communicating with the EGR passage (21);
A diffuser inlet passage area variable mechanism (38) for changing the inlet passage area of the diffuser (27);
The diffuser inlet passage area variable mechanism (38) is characterized in that the inlet passage area of the diffuser (27) is larger than the outlet passage area of the nozzle (26) by a value corresponding to the amount of EGR gas introduced. An EGR control device for an internal combustion engine.   The EGR control device for an internal combustion engine according to claim 1, further comprising a nozzle outlet passage area variable mechanism (33) for changing an outlet passage area of the nozzle (26). The intake passage (12) has a rectangular cross section at a portion where the venturi device (19) is provided,
The diffuser (27) includes a diffuser flap (36, 36U, 36L) whose downstream end is pivotally supported on the wall surface (12a, 12b) of the intake passage (12) and extends toward the upstream side,
When the EGR gas is introduced, the diffuser inlet passage area variable mechanism (38) moves the upstream end of the diffuser flap (36, 36U, 36L) from the wall surface (12a, 12b) of the nozzle (26). The downstream end of the inclined surface inclined in the separating direction is swung to a position close to the wall surface (12a, 12b) of the intake passage (12) by a value corresponding to the amount of EGR gas introduced. The EGR control device for an internal combustion engine according to claim 1. The nozzle (26) has an upstream end pivoted on the wall surface (12a, 12b) of the intake passage (12) and the nozzle flap (32, 32U). , 32L) and a nozzle outlet passage area variable mechanism (33) that swings,
When the EGR gas is not introduced, the diffuser inlet passage area variable mechanism (38) causes the diffuser flaps (36, 36U, 36L) to run along the wall surface (12a, 12b) of the intake passage (12) and the nozzle. The outlet passage area variable mechanism (33) makes the slit (28) disappear by moving the nozzle flap (32, 32U, 32L) along the wall surface (12a, 12b) of the intake passage (12). An EGR control device for an internal combustion engine according to claim 3. The nozzle (26) has an upstream end pivoted on the wall surface (12a, 12b) of the intake passage (12), the nozzle flap (32, 32U, 32L), and the nozzle flap (32, 32U, 32L) and a nozzle outlet passage area variable mechanism (33) that swings,
The EGR passage (21) opens to the wall surface (12a, 12b) of the intake passage (12) between the upstream end and the downstream end of the nozzle flap (32, 32U, 32L),
When EGR gas is not introduced, the nozzle outlet passage area variable mechanism (33) moves the nozzle flap (32, 32U, 32L) along the wall surface (12a, 12b) of the intake passage (12). The EGR control device for an internal combustion engine according to claim 3, wherein the EGR passage (21) opened to the wall surface (12a, 12b) is closed.

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