JP2005226579A - Exhaust gas recirculation device for engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance heat reduction effect of recirculating exhaust gas in a plate member for forming an exhaust gas recirculation passage interposed between an intake manifold and a cylinder head, enhance distribution performance to each cylinder and further improve intake air filling efficiency. <P>SOLUTION: An EGR plate 6 comprising a plate inner 7 in a head side and a plate outer 8 in a manifold side is arranged between the cylinder head and the intake manifold. Inside the EGR plate 6, the exhaust gas recirculation passage comprising a common passage part 34, upstream branch passage parts 35, 36 and downstream branch passage parts 37, 38 are formed by a groove of a jointed face of the plate inner 7 and the plate outer 8. In particular, the common passage part 34 is arranged in an extending portion protruded below a jointed face of the cylinder head and the intake manifold. A cooling water passage 49 having a closed cross sectional structure is provided in a manifold side from the common passage part 34 inside the plate outer 8 of the extending portion. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an exhaust gas recirculation device for an engine, and in particular, an in-line multi-cylinder engine that distributes and recirculates exhaust gas to an intake passage in the vicinity of an intake port of each cylinder via an exhaust gas recirculation passage including a common passage portion and a branch passage portion. The present invention relates to an exhaust gas recirculation apparatus.

  In recent years, in a vehicle engine, a part of the exhaust gas is extracted from the exhaust system and recirculated to the intake system, thereby reducing the pumping loss especially during low and medium load operation, improving the energy efficiency and improving the fuel efficiency. Things are going on. However, when such exhaust gas recirculation is performed, for example, if exhaust gas is recirculated to, for example, a surge tank portion upstream of the branch passage portion of the intake manifold in an in-line four-cylinder engine, the exhaust gas to each cylinder Dispersion is likely to occur. This is because the path through which the exhaust gas introduced into the surge tank section flows from the surge tank section toward the branch passage section of each cylinder depends on the direction and shape of the space inside the intake manifold.

  Therefore, in order to recirculate the exhaust gas evenly to each cylinder, the exhaust gas is also recirculated directly to the vicinity of the intake port of each cylinder, and such exhaust gas recirculation is called, for example, “port EGR”. With respect to the port EGR, a plate member for EGR (exhaust gas recirculation) is interposed between the flange portion of the cylinder head and the flange portion of the intake manifold, and a groove is formed between the plate member and the flange portion of the cylinder head. A so-called tournament-type exhaust gas recirculation passage (EGR passage) composed of a common passage portion, an upstream branch passage portion and a downstream branch passage portion for the intake ports of the plurality of cylinders; In the related art, a cooling rib is provided around the outer periphery of the substrate (for example, see Patent Document 1).

  However, in the conventional technology in which the exhaust gas recirculation passage is configured by such a plate member and a groove provided in the flange portion of the cylinder head, the cylinder head is dedicated to it and has a special specification. Therefore, the mold becomes complicated when the plate member is cast. Further, in the above conventional technique, among the exhaust gas recirculation passage in the tournament style, the upstream branch passage portion and the downstream branch passage portion are formed in the plate member, and the common passage portion is formed in the flange portion of the cylinder head. Since the common passage portion for EGR is formed, the flange portion of the cylinder head is enlarged, which prevents the engine from being made compact. Further, if the exhaust gas recirculation passage is formed across the plate member and the intake port flange portion in this way, the degree of freedom in designing the exhaust gas recirculation passage is reduced.

  Therefore, the present applicant has proposed a technique for solving such problems of the conventional port EGR in a previous application (Japanese Patent Application No. 2003-297401). In this technique, an EGR plate member formed by overlapping two divided plate bodies in the thickness direction is interposed between the intake manifold and the cylinder head, and a groove provided on a mating surface of each divided plate body An exhaust gas recirculation passage having an exhaust gas introduction portion, a common passage portion communicating with the exhaust gas introduction portion, and a branch passage portion branching from the common passage portion and distributing the exhaust gas toward the intake passage of each cylinder is formed. As a basic rule, the plate member is provided with an extending portion that protrudes outside the joint surface with the cylinder head and the joint surface with the intake manifold, and the common passage that is a particularly high-temperature portion of the exhaust gas recirculation passage is provided in the extended portion. It is to provide a part.

  According to the technology related to this earlier application, the recirculation ability of the recirculated exhaust gas to each cylinder can be improved, and the cylinder head does not have a special shape, so that the engine body can have versatility. The port EGR is not a restriction on the design of the cylinder head, and the degree of freedom in designing the exhaust gas recirculation passage is increased. And, without providing a special structure on the engine body (cylinder head) side, the heat of the recirculated exhaust gas can be effectively radiated in the plate member, and the influence of the heat of the recirculated exhaust gas is suppressed to fill the intake air. Efficiency can be improved. Further, it is possible to reduce the thermal influence on the intake manifold when the intake manifold is made of resin.

However, although the technology related to the previous application can dissipate the heat of the recirculated exhaust gas by providing the common passage portion of the exhaust gas recirculation passage in the extended portion of the plate member, the improvement of the intake charging efficiency by the heat radiation is limited. Is. Therefore, it is desired to further reduce the heat of the recirculated exhaust gas in the plate member and further improve the intake charging efficiency.
JP 2002-339809 A

  Accordingly, in the plate member for forming the exhaust gas recirculation passage interposed between the intake manifold and the cylinder head, the effect of reducing the heat of the recirculated exhaust gas is enhanced, and the distribution efficiency to each cylinder is enhanced while the intake charging efficiency is further increased. It is a problem to make it possible to improve this, and the solution of this problem is the object of the present invention.

  The present invention solves the above problems by an exhaust gas recirculation device for an engine according to claims 1 to 5.

  The exhaust gas recirculation device for an engine according to claim 1 is characterized in that the independent intake of the intake manifold connected to the end face of the cylinder head having an independent intake passage for each cylinder inside and an end face where each intake port of the cylinder head opens. The two divided plate bodies including an intake passage portion that is formed of two divided plate bodies that overlap each other in the thickness direction and that is part of an intake passage that communicates with the intake port of each cylinder. An exhaust gas recirculation passage having a common passage portion formed inside by a groove provided on the mating surface and a branch passage portion branching from the common passage portion and distributing the exhaust gas toward the intake passage of each cylinder is formed. Engine exhaust gas that distributes and recirculates exhaust gas to each intake passage that communicates with the intake port of each cylinder through the exhaust gas recirculation passage. The plate member has an extending portion that protrudes outside the joint surface of the plate member with the cylinder head and the joint surface with the intake manifold, and the exhaust gas recirculation passage is provided in the extended portion. The cooling water having a closed cross-sectional structure extending in the cylinder row direction is provided in the vicinity of the common passage portion of at least one of the divided plate bodies of the plate member. A passage is formed.

  This exhaust gas recirculation device distributes and recirculates exhaust gas to each intake passage communicating with the intake port of each cylinder through an exhaust gas recirculation passage composed of a common passage portion and a branch passage portion, thereby distributing the exhaust gas. The exhaust gas can be recirculated evenly to each cylinder, and the exhaust gas recirculation passage is formed only by the plate member arranged between the cylinder head and the intake manifold, and the cylinder head has a special shape. Therefore, the engine body can be made versatile, the port EGR is not a restriction on the design of the cylinder head, and the degree of freedom in designing the exhaust gas recirculation passage is increased. Further, by providing a common passage portion of the exhaust gas recirculation passage in the extended portion of the plate member, the heat of the recirculation exhaust gas can be dissipated, and the heat of the recirculation exhaust gas can be further reduced by the cooling water flowing through the cooling water passage. In addition, it is possible to improve the intake charging efficiency by suppressing the influence of the heat of the recirculated exhaust gas.

  An engine exhaust gas recirculation apparatus according to a second aspect is the engine exhaust gas recirculation apparatus according to the first aspect, wherein the two divided plate bodies constituting the plate member are on the side joined to the intake manifold. The split plate body is set to be thicker than the split plate body on the side joined to the cylinder head, and an intake control valve is provided in the intake passage portion of the split plate body on the side joined to the intake manifold. The cooling water passage is formed in the divided plate body on the side joined to the manifold.

  In this case, the operation stability of the intake control valve can be increased compared to that provided in the intake manifold, and the cooling water passage is arranged to make effective use of the thickness of the divided plate body, thereby saving space and recirculating. The cooling efficiency of exhaust gas is improved. In this case, since the intake manifold can be reduced in the depth direction by the amount of the intake control valve transferred to the plate member, the overall dimensions of the engine body, the plate member, and the intake manifold can be prevented from becoming unnecessarily large. .

  An engine exhaust gas recirculation device according to a third aspect is the engine exhaust gas recirculation device according to the second aspect, wherein the cooling water passage is disposed inside the divided plate body joined to the intake manifold side. It is characterized in that it is located closer to the intake manifold than the groove forming the portion.

  In this case, the cooling effect is high on the intake manifold side, and the thermal influence when the intake manifold is made of resin can be further suppressed.

  The exhaust gas recirculation device for an engine according to claim 4 is the exhaust gas recirculation device for an engine according to claim 1, wherein the extended portion of the plate member bulges downward toward the intake manifold or cylinder head, The cooling water passage is formed in the protruding portion.

  By forming the cooling water passage in such an arrangement, it is possible to reliably reduce the temperature of the recirculated exhaust gas while keeping the outer dimensions of the entire engine including the intake manifold compact. The plate member can be made thin so that the portion sandwiched between the cylinder head and the intake manifold does not hinder downsizing of the outer dimensions of the engine.

  An engine exhaust gas recirculation device according to a fifth aspect is the engine exhaust gas recirculation device according to the first aspect, wherein at least one of the plate member and the common passage portion is disposed across the intake passage portion of the plate member. At least a part of the negative pressure passage for operating the negative pressure actuator is formed by a groove provided in the divided plate body.

  In this case, the plate member for exhaust gas recirculation forms at least a part of the negative pressure passage for extracting the negative pressure for operating the negative pressure actuator. Therefore, the negative pressure passage can be simplified and the negative pressure actuator can be connected to the negative pressure actuator. Even when connecting the tubes with tubes, the handling of the tubes can be simplified.

  As described above, according to the present invention, the effect of reducing the heat of the recirculated exhaust gas is enhanced in the plate member for forming the exhaust gas recirculation passage interposed between the intake manifold and the cylinder head, and the distribution to each cylinder is improved. The intake charge efficiency can be further improved while increasing

  1 to 8 show a first example of the embodiment. 1 is a front view showing the intake manifold in a partial cross section at the top of the engine, FIG. 2 is a perspective view of the EGR plate and the EGR valve as viewed from the back side, FIG. 3 is a front view of the plate member, and FIG. 5 is a cross-sectional view taken along the line AA in FIG. 3, FIG. 6 is a cross-sectional view taken along the line BB in FIG. 1 (corresponding to the CC cross-section in FIG. 3), and FIG. FIG. 8 (corresponding to the CC section in FIG. 3) and FIG. 8 are DD sectional views in FIG. 1 (corresponding to the DD section in FIG. 3).

  The engine according to this embodiment (first example) is a crossflow type in-line four-cylinder engine mounted horizontally in an engine room of an automobile, and as shown in FIG. The intake ports 2 a, 2 b, 2 c, 2 d have a flange portion 3 that is open, and an intake manifold 4 is connected to the flange portion 3 of the cylinder head 1. An EGR plate (plate member) 6 shown in FIGS. 2 and 3 is disposed between the flange portion 5 on the cylinder head connection side of the intake manifold 4 and the flange portion 3 of the cylinder head 1.

  As shown in FIGS. 2 and 3, the EGR plate 6 is made of aluminum alloy and has different thicknesses formed by die casting, both of the plate inner 7 on the cylinder head 1 side and the plate outer 8 on the intake manifold side. It consists of a single divided plate body, which are stacked in the thickness direction with a metal gasket (not shown) interposed therebetween, and are fastened and fixed integrally with screws. The plate inner 7 has a thin plate shape, and the plate outer 8 has a thicker plate shape. An SCV (swirl control valve) 10 as an intake control valve is incorporated in the thick plate outer 8.

  The intake manifold 4 is entirely made of synthetic resin and is composed of a plurality of divided bodies. Each of the manifold divided bodies is fixed between joint surfaces by, for example, vibration welding. A common passage portion and a surge tank (not shown) are upstream. And four branch passage portions 4a, 4b, 4c, 4d that branch from the surge tank portion downstream and communicate with the intake ports 2a, 2b, 2c, 2d of each cylinder independently. A variable intake valve (not shown) for adjusting the intake air amount is built in an intermediate portion of the passage portions 4a, 4b, 4c, 4d. The intake manifold 4 has a vacuum chamber (a vacuum chamber) that stores intake negative pressure between a branch passage portion 4b communicating with the intake port 2b of the second cylinder and a branch passage portion 4c communicating with the intake port 2c of the third cylinder. (Not shown) is provided.

  The EGR plate 6 is provided with each intake opening 31 that becomes a part of the intake passage corresponding to each intake port 2a, 2b, 2c, 2d that opens to the intake port flange portion 3 of the cylinder head 1, and an intake manifold 4 is provided with a bolt insertion hole 32 for fastening the bolt to the cylinder head 1 together.

  Further, the EGR plate 6 has an exhaust gas introduction portion 33 that communicates with an exhaust gas supply portion for EGR (exhaust gas recirculation) provided on the flange portion 3 of the cylinder head 1 on one end side (rear end side of the engine). A common passage portion 34 provided therein and extending in communication with the exhaust gas introduction portion 33; a pair of upstream branch passage portions 35, 36 extending separately from the common passage portion 34 to the left and right; and each upstream branch passage portion A pair of downstream branch passages 37, 38 and 39, 40 extending separately from the leading ends of 35, 36, respectively, distribute exhaust gas in the vicinity of the intake ports 2a, 2b, 2c, 2d of the four cylinders. A so-called tournament-style exhaust gas recirculation passage is provided.

  The common passage portion 34, the upstream branch passage portions 35, 36 and the downstream branch passage portions 37, 38, 39, 40 of the exhaust gas recirculation passage are substantially halved on the mating surfaces of the plate inner 7 and the plate outer 8. It is formed by the provided groove, the passage sectional area of the upstream branch passage portions 35, 36 is larger than the passage sectional area of the downstream branch passage portions 37-40, and the passage sectional area of the common passage portion 34 is the upstream branch passage portions 35, 36. It is comprised so that it may become still larger than passage cross-sectional area.

  Further, the exhaust gas introducing portion 33 is formed by an enlarged portion of a groove provided in the plate inner 7, and the central portion thereof opens to the cylinder head side. The exhaust gas introduction portion 33 is provided with a baffle 42 on one side that serves as a resistance when exhaust gas introduced from the cylinder head 1 side flows into the common passage portion 34. The exhaust gas introduced from the exhaust gas supply section 41 of the cylinder head 1 dissipates heat due to rapid expansion due to entering the expanded exhaust gas introduction section 21 inside the plate member 6 and pressure loss due to the baffle 42, and the temperature decreases.

  The exhaust gas recirculation passage inside the EGR plate 6 has the distal ends of the downstream branch passages 37, 38, 39, 40 opened to the respective intake openings 31, and the front end opening portion is provided with a throttle 43 as shown in FIG. In other words, the downstream side of the throttle 43 is formed to expand in a tapered shape. The exhaust gas distributed to each cylinder through the exhaust gas recirculation passage inside the plate member 6 is adjusted in variation by the throttle 43, and the downstream side of the throttle 43 spreads in a taper shape, resulting in a smooth flow with little resistance, Oil mist and carbon accumulation are also prevented.

  The EGR plate 6 has a portion extending downward, and this portion protrudes below the mating surface with the cylinder head 1 and the mating surface with the intake manifold 4 as shown in FIGS. . And in the part which protrudes, most of the said common channel | path part 34 and the upstream part of the upstream branch channel | path parts 35 and 36 are provided.

  Inside the plate member 6, most of the mating surfaces of the plate inner 7 and the plate outer 8 are provided on the plate outer 8 side, and a part thereof is provided with a groove provided on the plate inner 7 side. A negative pressure extraction passage 44 is formed as a part of the negative pressure passage for extracting the negative pressure for operating the negative pressure actuator from the vacuum chamber.

  The negative pressure take-out passage 44 is formed on the plate member 6 from the substantially upper center between the two inner intake openings 31 corresponding to the intake port 2b of the second cylinder and the intake port 2c of the third cylinder. The exhaust gas recirculation passage is divided into an upper side and a lower side across the intake opening 31 of the plate member 6 and is arranged apart from each other, extending to the upper end side (the engine rear end side). ing.

  Then, as shown in FIG. 3, the negative pressure is taken out at a position which is substantially in the upper center between the two inner intake openings 31 of the plate outer 8 which is a divided plate body arranged on the intake manifold 4 side. A hole 45 for opening one end side of the passage 44 to the mating surface with the intake manifold 4 is provided, and the negative pressure extraction passage 44 and a vacuum chamber (not shown) are configured to communicate with each other through the hole 45.

  Further, a plate outer 8 which is a divided plate body arranged on the intake manifold 4 side is provided with a hole 46 opened to the outer surface above a portion located at the other end of the negative pressure extraction passage 44. As shown in FIGS. 3 and 4, a connecting pipe portion 47 made of a pipe material is provided so that a tube as an external negative pressure passage is fitted into the hole 46. Then, the plate inner 7 which is the divided plate body arranged on the cylinder head 1 side is expanded so that the other end communicates with the hole 46 provided with the connecting pipe portion 47 as a part of the negative pressure extraction passage 44. The communication path 48 is formed.

  Further, in the EGR plate 6, a portion of the plate outer 8 that protrudes below the mating surface with the cylinder head 1 and the mating surface with the intake manifold 4 is formed on the intake manifold 4 side from the groove forming the common passage portion 34 inside the plate outer 8. As shown in FIGS. 3 and 5 to 7, a cooling water passage 49 having a closed cross-sectional structure extending substantially straight in the cylinder row direction is formed along the common passage portion 34. The cooling water passage 49 can be formed by casting or machining. As shown in FIGS. 5 to 7, it is provided on the intake manifold side with respect to the groove forming the common passage portion 34 of the exhaust gas recirculation passage inside the plate outer 8. Then, one end (rear side end portion) of the cooling water passage 49 opens toward the intake manifold side as shown in FIGS. 3 and 5, and a connecting pipe member 50 is provided in the opening portion. The other end (front side end) of the cooling water passage 49 opens to the side surface of the downwardly extending portion of the EGR plate 6 between the two intake openings 31 on the front side, and a connecting pipe member is connected to the opening. 51 is provided.

  As shown in FIG. 2, the cooling water passage 49 is connected to a connection pipe member 50 on one end (rear side end) side with a first hose 53 connected to a water-cooled EGR control valve 52, and the other end. A second hose 55 connected to a return hose 54 for returning cooling water from the engine body to a radiator (not shown) is connected to the connecting pipe member 51 on the (front side end) side.

  9 to 12 show a second example of the embodiment. 9 is a front view of the plate member, FIG. 10 is a right side view of the plate member, FIG. 11 is a cross-sectional view of the upper part of the engine shown in FIG. 9 taken along the line BB, and FIG. It is sectional drawing represented with the cross section.

  This embodiment (second example) is a thick divided plate body in which the EGR plate 6 is constituted by a thin plate inner 7 and a plate outer 8 thicker than the EGR plate 6 in the first example of the above embodiment. While the SCV (swirl control valve) 10 is incorporated in the plate outer 8, an EGR plate 6A consisting of two thin plate-like divided plate bodies (plate inner 7A and plate outer 8A) is used, and the manifold An intake control valve 10A is arranged on the 4th side.

  In this example, the common passage portion 34 is an upstream portion close to the exhaust gas introduction portion 33, and the cross-sectional shape is vertically long as shown in FIG. 12 in order to increase the cross-sectional area, and is parallel to one upstream branch passage portion 36. In the downstream portion having the above arrangement, the cross-sectional shape is horizontally long as shown in FIG. 11 so that the cross-sectional area can be increased while avoiding interference with the parallel upstream branch passage portions 36. And the part by which the cross-sectional shape of the common channel | path part 34 was made horizontally long of the upstream branch channel | path part 36 in which the channel | path cross-sectional center in the thickness direction of EGR plate 6A is located in the mating surface of the plate inner 7A and the plate outer 8A. The EGR plate 6A is arranged to be offset to the cylinder head 1 side from the passage cross-sectional center, and the thickness dimension of the portion corresponding to the offset arrangement portion of the common passage portion 34 is larger than the thickness dimension of other portions. It is configured such that a portion where the thickness dimension is large and protrudes to the lower side of the flange portion 3 of the cylinder head 1 is configured.

  Further, the EGR plate 6A has one end side in the cylinder row direction (the engine rear end side) in which the common passage portion 34 of the exhaust gas recirculation passage and the passage portion close to the hole 46 on the outlet side of the negative pressure extraction passage 44 are arranged vertically. Further, through spaces 49, 50, 51 are provided that thermally block between the common passage portion 34 of the exhaust gas recirculation passage and the negative pressure extraction passage 44.

  As shown in FIGS. 11 and 12, a portion of the plate outer 8A of the extending portion of the EGR plate 6A bulges downward toward the intake manifold 4, and a cooling water passage 49 is formed in the bulged portion. Yes.

  Other configurations are the same as in the first example, and the operation is basically the same as in the first example. Therefore, detailed description of common matters is omitted. 9-12, the same code | symbol is attached | subjected to the part which is common in a 1st example.

  13 and 14 show a third example of the embodiment. 13 is a cross-sectional view corresponding to the BB cross section of the second example of the upper part of the engine, and FIG. 14 is a cross-sectional view corresponding to the CC cross section of the second example of the upper part of the engine.

This embodiment (third example) uses an EGR plate 6B composed of two thin plate-like divided plate bodies (plate inner 7B and plate outer 8B). A portion of the inner 7A bulges downward toward the cylinder head 1, and a cooling water passage 49 is formed in the bulged portion.
Other configurations are the same as in the second example, and the operation is basically the same as in the second example. Therefore, detailed description of common matters is omitted. In FIG. 13 and FIG. 12, the same code | symbol is attached | subjected to the part which is common in a 1st example and a 2nd example.

It is a front view which shows the intake manifold of the engine upper part in the 1st example of embodiment with a partial cross section. It is the perspective view seen from the back side of the EGR plate and EGR valve in the 1st example of an embodiment. It is a front view of the plate member in the 1st example of an embodiment. It is a right view of the plate member in the 1st example of an embodiment. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. 1 (equivalent to CC cross section of FIG. 3). It is CC sectional drawing of FIG. 1 (equivalent to CC cross section of FIG. 3). It is DD sectional drawing of FIG. 1 (equivalent to the DD cross section of FIG. 3). It is a front view of the plate member in the 2nd example of an embodiment. It is a right view of the plate member in the 2nd example of an embodiment. FIG. 10 is a cross-sectional view of the upper part of the engine in the second example of the embodiment, represented by a BB cross section in FIG. FIG. 10 is a cross-sectional view of the upper part of the engine in the second example of the embodiment, taken along the line CC in FIG. It is sectional drawing equivalent to the BB cross section of the 2nd example of the engine upper part in the 3rd example of embodiment. It is sectional drawing equivalent to CC section of the 2nd example of the engine upper part in the 3rd example of an embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder head 2a, 2b, 2c, 2d Intake port 3 Cylinder head flange part 4 Intake manifold 4a, 4b, 4c, 4d Branch passage part 5 Intake manifold flange part (cylinder head side)
6, 6A, 6B EGR plate 7, 7A, 7B Plate inner 8, 8A, 8B Plate outer 10 SCV (swirl control valve)
10A Intake control valve 31 Intake opening portion 33 Exhaust gas introduction portion 34 Common passage portion 35, 36 Upstream branch passage portion 37, 38, 39, 40 Downstream branch passage portion 44 Negative pressure extraction passage 49 Cooling water passage 50, 51 Connecting pipe member

Claims (5)

Between the end face where each intake port of the cylinder head opens and the end face where the independent intake passage of the intake manifold which has an independent intake passage for each cylinder and is connected to the end face of the cylinder head opens in the thickness direction An intake passage portion that is formed of two overlapping divided plate bodies and serves as a part of an intake passage communicating with the intake port of each cylinder, and is formed inside by a groove provided on a mating surface of the two divided plate bodies. A metal plate member that forms an exhaust gas recirculation passage that includes a common passage portion and a branch passage portion that branches off from the common passage portion and distributes the exhaust gas toward the intake passage of each cylinder; An exhaust gas recirculation device for an engine that distributes and recirculates exhaust gas to each intake passage communicating with the intake port of each cylinder by a recirculation passage,
The plate member has an extending portion that protrudes outside the joint surface of the plate member with the cylinder head and the joint surface with the intake manifold, and at least the common passage in the exhaust gas recirculation passage is formed in the extended portion. A cooling water passage having a closed cross-sectional structure extending in the cylinder row direction is formed in the vicinity of the common passage portion of at least one of the divided plate bodies of the plate member. An exhaust gas recirculation device for an engine. The two divided plate bodies constituting the plate member are set so that the divided plate body on the side joined to the intake manifold is thicker than the divided plate body on the side joined to the cylinder head. 2. An intake control valve is provided in the intake passage portion of the divided plate body on the side to be connected, and the cooling water passage is formed in the divided plate body on the side joined to the intake manifold. An exhaust gas recirculation device for an engine according to 1. 3. The engine according to claim 2, wherein the cooling water passage is located on the intake manifold side with respect to a groove forming the common passage portion inside the divided plate body joined to the intake manifold side. 4. Exhaust gas recirculation device. 2. The engine exhaust according to claim 1, wherein the extended portion of the plate member bulges downward toward the intake manifold side or the cylinder head side, and the cooling water passage is formed in the bulged portion. Gas reflux device. At least a part of the negative pressure passage for operating the negative pressure actuator is formed by a groove provided in at least one divided plate body on the opposite side of the intake passage portion of the plate member from the common passage portion. The exhaust gas recirculation device for an engine according to claim 1, wherein

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