CN211975215U

CN211975215U - Engine for vehicle

Info

Publication number: CN211975215U
Application number: CN202020478307.3U
Authority: CN
Inventors: 重松大吾
Original assignee: Suzuki Motor Corp
Current assignee: Suzuki Motor Corp
Priority date: 2019-04-26
Filing date: 2020-03-31
Publication date: 2020-11-20
Anticipated expiration: 2030-03-31
Also published as: DE102020204285B4; DE102020204285A1; JP7196754B2; JP2020180606A

Abstract

The utility model provides an engine for vehicle, under the circumstances that the part of admitting air of installing in the upstream side of air intake manifold disposes near EGR cooler's waste gas entry, also can improve air intake manifold and EGR cooler's supporting rigidity. The plurality of branch pipes (41, 42, 43, 44) include at least one branch pipe (42) as a curved branch pipe curved such that a downstream end thereof is offset in the cylinder row direction to a side opposite to the side where the throttle valve body (23) is located with respect to an upstream end thereof. The EGR cooler (24) is fixed to the intake manifold (40) at a position closer to the throttle body than the branch pipe (42) in the direction of the bank. The EGR valve (26) is disposed above the branch pipe (42) and is fixed to the upper portion of the EGR pipe (31). The EGR pipe extends along the upper surface of the branch pipe (42) toward the upper surface of the surge tank (45), and the EGR pipe is connected to the upper surface of the branch pipe (42) and the upper surface of the surge tank and integrated with the branch pipe (42) and the surge tank.

Description

Engine for vehicle

Technical Field

The utility model relates to an engine for vehicle.

Background

Conventionally, as a vehicle engine, a vehicle engine described in patent document 1 is known. In the vehicle engine described in patent document 1, an EGR cooler is mounted on an upper portion of an intake manifold. An EGR pipe is connected to the EGR cooler, and a cooling case in which a refrigerant circulates is integrally provided to the EGR pipe. The EGR cooler is connected to the cylinder head by an EGR pipe, and the connection improves the support rigidity of the EGR cooler and the intake manifold by the cylinder head.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2015-190416

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

Here, a throttle valve body (japanese: スロットルボディ) as an intake member is usually attached to the intake manifold on the upstream side in the intake air flow direction, and the intake member and the EGR cooler may be disposed close to each other.

However, the technique described in patent document 1 cannot be applied to a case where an intake member attached to the upstream side of an intake manifold is disposed in the vicinity of an exhaust gas inlet of an EGR cooler for a space reason, and there is a problem that the support rigidity of the intake manifold and the EGR cooler cannot be improved.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle engine in which the support rigidity of an intake manifold and an EGR cooler can be improved even when an intake member attached to the upstream side of the intake manifold is disposed in the vicinity of an exhaust gas inlet of the EGR cooler.

Means for solving the problems

The utility model discloses an engine for vehicle's characterized in that, include: a cylinder head having a plurality of intake ports arranged side by side in a cylinder row direction; an intake manifold having a surge tank extending in the cylinder row direction and a plurality of branch pipes connecting the plurality of intake ports to the surge tank, respectively, in the order of arrangement in the cylinder row direction; an intake member connected to an upstream end of the surge tank, the intake member adjusting an amount of air flowing into the surge tank; an EGR cooler that is disposed above the intake manifold and through which exhaust gas passes in the bank direction; an EGR valve connected to an exhaust gas outlet of the EGR cooler; and an EGR pipe that guides exhaust gas from the EGR valve to the surge tank, an upstream end of the surge tank being disposed on one side of an outer intake port located at an end portion in the cylinder row direction among the plurality of intake ports, a downstream end of the surge tank being disposed on one side of an inner intake port located at a central portion in the cylinder row direction among the plurality of intake ports, the plurality of branch pipes including at least one curved branch pipe that is curved such that a downstream end thereof is offset in the cylinder row direction with respect to an upstream end thereof toward a side opposite to the side where the intake member is located, the EGR cooler being fixed to the intake manifold at a position closer to the side where the intake member is located than the curved branch pipe in the cylinder row direction, the EGR valve being disposed above the curved branch pipe and fixed to an upper portion of the EGR pipe, the EGR pipe extending along an upper surface of the curved branch pipe toward an upper surface of the surge tank, the EGR pipe is connected to an upper surface of the bent branch pipe and an upper surface of the surge tank and integrated with the bent branch pipe and the surge tank.

Preferably, in the vehicle engine, the EGR valve has an EGR valve side flange portion connected to the EGR pipe, and an EGR pipe side flange portion extending upward and connected to the EGR valve side flange portion is provided at an upper end of the EGR pipe.

Preferably, in the vehicle engine, the intake manifold has a flange portion that connects the branch pipes to the intake ports, the branch bent pipe has a connecting rib that connects an upper surface of the branch bent pipe and the flange portion, and the EGR pipe is connected to the flange portion by the connecting rib.

In the vehicle engine, it is preferable that the EGR cooler is fixed to the surge tank by a bracket, and the bracket connects the surge tank and the cylinder head.

Effect of the utility model

As described above, according to the present invention, it is possible to provide a vehicle engine in which the support rigidity of the intake manifold and the EGR cooler can be improved even when the intake member attached to the upstream side of the intake manifold is disposed in the vicinity of the exhaust gas inlet of the EGR cooler.

Drawings

Fig. 1 is a left side view of a vehicle engine according to an embodiment of the present invention.

Fig. 2 is a plan view of a vehicle engine according to an embodiment of the present invention.

Fig. 3 is a rear view of an upper portion of a vehicle engine according to an embodiment of the present invention.

Fig. 4 is a left side view of an intake manifold of a vehicle engine according to an embodiment of the present invention.

Fig. 5 is a rear view of an intake manifold of a vehicle engine according to an embodiment of the present invention.

Fig. 6 is a rear view of an intake manifold and a bracket of a vehicle engine according to an embodiment of the present invention.

Fig. 7 is a perspective view of an intake manifold of a vehicle engine according to an embodiment of the present invention.

Fig. 8 is a perspective view of an intake manifold, an EGR cooler, and a bracket of a vehicle engine according to an embodiment of the present invention.

Description of the reference numerals

1. An engine (vehicle engine); 12. a cylinder cover; 23. a throttle valve body (intake member); 24. an EGR cooler; 26. an EGR valve; 26A, EGR valve side flange portion; 31. an EGR tube; 31C, EGR pipe side flange part; 35. a support; 40. an intake manifold; 41. 42, 43, 44, a branch pipe; 45. a voltage stabilizing box; 46. a connecting rib; 48. an outlet-side flange portion (flange portion); 61. 62, an air inlet; 63. an air inlet (inside air inlet); 64. air inlet (outside air inlet).

Detailed Description

The utility model discloses an embodiment's engine for vehicle's characterized in that, include: a cylinder head having a plurality of intake ports arranged side by side in a cylinder row direction; an intake manifold having a surge tank extending in a cylinder row direction and a plurality of branch pipes connecting a plurality of intake ports to the surge tank, respectively, in an order of arrangement in the cylinder row direction; an intake member connected to an upstream end of the surge tank, the intake member adjusting an amount of air flowing into the surge tank; an EGR cooler disposed above the intake manifold, through which exhaust gas passes in a cylinder row direction; an EGR valve connected to an exhaust gas outlet of the EGR cooler; and an EGR pipe that guides exhaust gas from the EGR valve to the surge tank, an upstream end of the surge tank being disposed on one side of an outer intake port located at an end portion in the cylinder row direction among the plurality of intake ports, a downstream end of the surge tank being disposed on one side of an inner intake port located at a central portion in the cylinder row direction among the plurality of intake ports, the plurality of branch pipes including at least one bent branch pipe, the curved branch pipe is curved such that a downstream end thereof is offset in the direction of the bank with respect to an upstream end thereof to a side opposite to the side where the intake member is located, the EGR cooler is fixed to the intake manifold at a position closer to the side where the intake member is located than the curved branch pipe in the direction of the bank, the EGR valve is disposed above the curved branch pipe, and is fixed on the upper part of the EGR pipe, the EGR pipe extends to the upper surface of the pressure stabilizing box along the upper surface of the bending branch pipe, and the EGR pipe is connected with the upper surface of the bending branch pipe and the upper surface of the pressure stabilizing box and is integrated with the bending branch pipe and the pressure stabilizing box. Thus, in the vehicle engine according to the embodiment of the present invention, even when the intake member attached to the upstream side of the intake manifold is disposed in the vicinity of the exhaust gas inlet of the EGR cooler, the support rigidity of the intake manifold and the EGR cooler can be improved.

Examples

Hereinafter, a vehicle engine according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 to 8 are diagrams showing a vehicle engine according to an embodiment of the present invention. In fig. 1 to 8, the vertical, front, rear, and left and right directions are the vertical, front, rear, and left and right directions of the vehicle engine in a state of being installed in the vehicle, the direction orthogonal to the front and rear directions is the left and right direction, and the height direction of the vehicle engine is the vertical direction.

First, the structure is explained. In fig. 1, an engine 1 as a vehicle engine includes an engine body 10 and an equipment member described later provided to the engine body 10. The engine body 10 includes a cylinder block 11, a cylinder head 12, a cylinder head cover 13, and an oil pan 14 for storing lubricating oil.

The cylinder block 11 is provided with a plurality of cylinders 10A (see fig. 2). Hereinafter, the arrangement direction of the plurality of cylinders 10A is also referred to as a cylinder row direction. The engine 1 of the present embodiment includes a four-cylinder engine having four cylinders 10A, but is not limited to the four-cylinder engine.

A piston, not shown, is housed in the cylinder 10A, and the piston reciprocates in the vertical direction with respect to the cylinder. The piston is connected to a crankshaft 11A (see fig. 1) via a connecting rod (not shown), and the reciprocating motion of the piston is converted into rotational motion of the crankshaft 11A via the connecting rod.

In fig. 3, a chain case 15 is fastened to a right end portion of the cylinder block 11 and the cylinder head 12 in the cylinder row direction. The chain case 15 covers a timing chain, not shown, disposed at the right end portions of the cylinder block 11 and the cylinder head 12.

Here, the bank direction of the engine 1 is the left-right direction, i.e., the vehicle width direction. Therefore, the engine 1 is disposed in a vehicle not shown in the drawings so as to be laterally disposed.

In fig. 2, the cylinder head 12 is provided with a plurality of

intake ports

61, 62, 63, 64 that communicate with the plurality of cylinders 10A, respectively. The plurality of

intake ports

61, 62, 63, 64 are arranged side by side in the cylinder row direction. The cylinder head 12 is provided with an intake valve, a plurality of exhaust ports, a plurality of exhaust valves for opening and closing the exhaust ports, and the like, and none of the intake valve, the plurality of exhaust ports, and the plurality of exhaust valves for opening and closing the exhaust ports are shown.

An intake manifold 40 is provided on the rear surface of the cylinder head 12, and the intake manifold 40 introduces intake air into each cylinder 10A through

intake ports

61, 62, 63, and 64.

An exhaust manifold, not shown, is formed inside the cylinder head 12. The exhaust manifold has a plurality of exhaust ports (not shown) communicating with the cylinders 10A, and collects exhaust gas (also referred to as exhaust gas or exhaust gas) discharged from the cylinders 10A. That is, an exhaust manifold integrated with an exhaust port is formed inside the cylinder head 12.

The exhaust manifolds have a common collective exhaust outlet, not shown. The central portion of the collective exhaust outlet in the cylinder row direction opens to the front surface of the cylinder head 12.

The exhaust gas discharged from the cylinder 10A is collected at the exhaust manifold, and then discharged to the outside of the cylinder head 12 from the collected exhaust gas outlet.

In fig. 1 and 2, a turbocharger 20 is provided on the front surface side of the cylinder head 12, and the upstream end of the turbocharger 20 in the exhaust passage is connected to the collective exhaust outlet. The turbocharger 20 compresses intake air by using energy of exhaust gas introduced from the collective exhaust outlet. The air compressed by the turbocharger 20 is introduced into the intake manifold 40.

An exhaust gas purification device 25 is disposed on the left side of the turbocharger 20, and the exhaust gas purification device 25 extends in the vertical direction at the left end portion on the front surface side of the engine main body 10.

An exhaust inlet 25A at the upper end of the exhaust purification device 25 is connected to the downstream end of the turbocharger 20 in the exhaust path.

A three-way catalyst (three-way catalyst) and a particulate filter (not shown) are housed in the exhaust gas purification device 25. Three-way catalyst for HC, CO, NO contained in exhaust gas by oxidation-reduction reaction_xAnd simultaneously carrying out purification treatment.

The Particulate filter is provided downstream of the three-way catalyst, and traps graphite, which is Particulate Matter (PM) in the exhaust gas, a combustion residue (SOF) of fuel, a combustion residue (ash) of engine oil, and the like.

An exhaust pipe, not shown, is connected to the exhaust outlet portion 25B at the lower end of the exhaust purification device 25.

The exhaust gas having passed through the turbocharger 20 is purified by an exhaust gas purification device 25 and discharged to the outside of the vehicle through an exhaust pipe.

The exhaust gas inlet 25A of the exhaust gas purification device 25 is open on the side where the turbocharger 20 is located, and is connected to the turbocharger 20.

In fig. 4, 5, and 7, the intake manifold 40 has a surge tank 45 and a plurality of

branch pipes

41, 42, 43, 44, the surge tank 45 extending in the bank direction, the plurality of

branch pipes

41, 42, 43, 44 connecting the surge tank 45 and a plurality of

intake ports

61, 62, 63, 64 in the order of arrangement in the bank direction.

The plurality of

branch pipes

41, 42, 43, 44 are curved in an upwardly convex shape and extend from the surge tank 45 toward the cylinder head 12, and downstream ends of the plurality of

branch pipes

41, 42, 43, 44 are connected to the

intake ports

61, 62, 63, 64 on the rear surface of the cylinder head 12.

In fig. 1, 3, and 8, the engine 1 has a throttle valve body 23 as an intake member that adjusts the amount of air flowing into a surge tank 45 of an intake manifold 40. The throttle valve body 23 is connected to an upstream end 45A (see fig. 5) of the surge tank 45 at the left end portion. The throttle valve body 23 is connected to the surge tank 45 in a posture in which air passes through the inside thereof in the direction of the bank. Therefore, the air having passed through the throttle valve body 23 flows in the bank direction in the surge tank 45. The right end of the surge tank 45 is the end on the downstream side of the exhaust gas flowing in the direction of the cylinder row, and constitutes a downstream end 45B (see fig. 5).

In fig. 1, the engine 1 includes an exhaust return pipe 21, an exhaust return passage 12A formed in a cylinder head 12, a connection pipe 22, and an EGR cooler 24.

The exhaust return pipe 21 extends in the vertical direction along the left side surface of the exhaust purification device 25. The exhaust return pipe 21 connects the exhaust outlet portion 25B of the exhaust purification device 25 to the exhaust return passage 12A, and introduces the exhaust gas purified by the exhaust purification device 25 into the exhaust return passage 12A.

The connection pipe 22 is disposed near the left end portion of the rear surface of the cylinder head 12, and connects the exhaust gas return passage 12A and the EGR cooler 24.

The exhaust return passage 12A extends in the front-rear direction inside the left side surface of the cylinder head 12, and introduces the exhaust gas introduced from the exhaust return pipe 21 on the front surface side of the cylinder head 12 into the connection pipe 22 on the back surface side of the cylinder head 12.

In fig. 2, 3, and 8, the EGR cooler 24 is disposed above the intake manifold 40 in a posture extending in the bank direction. The EGR cooler 24 has a main body portion 24A, an exhaust gas intake portion 24B that takes in exhaust gas, and an exhaust gas outlet portion 24C that discharges exhaust gas. The exhaust gas intake portion 24B constitutes an inlet portion of exhaust gas to the EGR cooler 24. The exhaust gas outlet portion 24C constitutes an outlet portion of exhaust gas with respect to the EGR cooler 24.

The exhaust gas suction portion 24B is connected to the connection pipe 22.

A cooling water introduction pipe 24D that introduces cooling water and a cooling water discharge pipe 24E that discharges cooling water are connected to the body portion 24A of the EGR cooler 24. The main body portion 24A cools the exhaust gas by heat exchange with the cooling water.

An EGR valve 26 is connected to an exhaust gas outlet portion 24C at the right end portion of the EGR cooler 24, and the EGR valve 26 adjusts the amount of exhaust gas passing through the EGR cooler 24.

In fig. 3, the engine 1 includes an EGR pipe 31, and the EGR pipe 31 guides the exhaust gas that has passed through the EGR valve 26 to a surge tank 45. The EGR pipe 31 connects the EGR valve 26 and the surge tank 45, and guides the exhaust gas whose flow rate is adjusted by the EGR valve 26 to the surge tank 45.

Here, an unillustrated exhaust gas passage through which exhaust gas passes is formed inside the EGR pipe 31. The EGR pipe 31 guides the exhaust gas taken in from the inlet side end portion 31A connected to the EGR valve 26 to the outlet side end portion 31B connected to the surge tank 45 via an exhaust gas passage. The lower surface of the EGR pipe 31 at the outlet-side end 31B communicates with the internal space of the surge tank 45.

In fig. 2 and 5, the upstream end 45A of the surge tank 45 is disposed on the side (rear) of the intake port 64 located at the end in the bank direction among the plurality of

intake ports

61, 62, 63, 64. The air inlet 64 constitutes an outside air inlet in the present invention.

The downstream end 45B of the surge tank 45 is disposed on the side (rear side) of the intake port 63 located at the center portion in the bank direction among the plurality of

intake ports

61, 62, 63, 64.

The air inlet 63 constitutes an inner side air inlet in the present invention.

In fig. 3 and 5, the

branch pipes

41 and 42 are bent such that the end portions on the cylinder head 12 side, that is, the downstream ends thereof are offset in the cylinder row direction from the end portions on the surge tank 45 side, that is, the upstream ends thereof, to the side opposite to the side where the throttle valve body 23 is located. The

branch pipes

41, 42 constitute the bending branch pipe in the present invention.

In this way, the plurality of

branch pipes

41, 42, 43, 44 includes at least one

branch pipe

41, 42 as a bending branch pipe. The EGR cooler 24 is fixed to the intake manifold 40 at a position closer to the throttle valve body 23 than the branch pipe 42 in the bank direction.

The EGR valve 26 is disposed above a branch pipe 42, which is one of the bent branch pipes, and is fixed to an upper portion of the EGR pipe 31. The EGR pipe 31 extends along the upper surface of the branch pipe 42 toward the upper surface of the surge tank 45, and the EGR pipe 31 is connected to the upper surface of the branch pipe 42 and the upper surface of the surge tank 45 and is integrated with the branch pipe 42 and the surge tank 45.

In fig. 3, 5, and 8, the EGR valve 26 has an EGR valve side flange portion 26A connected to the EGR pipe 31. On the other hand, an EGR pipe side flange portion 31C extending upward and connected to the EGR valve side flange portion 26A is provided at the upper end of the EGR pipe 31. The EGR valve side flange portion 26A is fixed to the EGR pipe side flange portion 31C by fastening bolts 37 (see fig. 8). A branch pipe side flange portion 42A (see fig. 5) is formed in the branch pipe 42, and the branch pipe side flange portion 42A is connected to the EGR pipe side flange portion 31C and is integrated with the EGR pipe side flange portion 31C.

In fig. 4 and 5, the intake manifold 40 has an inlet-side flange portion 47 that connects the surge tank 45 to the throttle body 23. The intake manifold 40 also has an outlet-side flange 48 that connects the

branch pipes

41, 42, 43, and 44 to the

intake ports

61, 62, 63, and 64. The outlet side flange portion 48 constitutes a flange portion in the present invention.

Here, as shown in fig. 4, the intake manifold 40 is formed by integrating an upper member 40A constituting a portion on the upper surface side and a lower member 40B constituting a portion on the lower surface side. Specifically, the lower surface side portion of the surge tank 45, the lower surface side portions of the

branch pipes

41, 42, 43, and 44, the inlet-side flange portion 47, and the outlet-side flange portion 48 are formed by the lower member 40B. Further, the upper surface side portion of surge tank 45 and the upper surface side portions of

branch pipes

41, 42, 43, and 44 are formed by upper member 40A.

The

branch pipes

41, 42, 43, and 44 are formed with coupling ribs 46 that couple the upper surfaces thereof to the outlet-side flange 48. The EGR pipe 31 is connected to the outlet-side flange 48 via the connecting rib 46.

In fig. 2, 3, and 6, a bracket 35 is disposed between the intake manifold 40 and the EGR cooler 24 located thereabove. The bracket 35 includes a member formed by bending a flat plate-like metal or the like into a curved shape along the upper surface of the intake manifold 40.

The EGR cooler 24 is fixed to a connection portion 35A (see fig. 6) at the center of the bracket 35 by fastening two bolts 37. An EGR bracket 36 (see fig. 2) is fixed to a lower surface of the EGR cooler 24, and the EGR cooler 24 is fixed to the connection portion 35A of the bracket 35 via the EGR bracket 36.

In fig. 6, bracket 35 has coupling portion 35C extending rearward from coupling portion 35A, and coupling portion 35C is fixed to the upper surface of surge tank 45 by fastening one bolt 37. The connecting portion 35C constitutes the surge tank side connecting portion in the present invention. A boss 40C (see fig. 5) for receiving the bolt 37 is formed on the upper surface of the surge tank 45. The boss portion 40C is disposed on the front end side of the surge tank 45 and is a portion between the branch pipe 43 and the branch pipe 44 in the cylinder row direction.

The bracket 35 has a coupling portion 35B extending forward from the coupling portion 35A, and the coupling portion 35B is fixed to

bosses

12B and 12C formed at the upper end portion on the rear surface side of the cylinder head 12 by fastening two bolts 37. The coupling portion 35B constitutes a cylinder head-side coupling portion in the present invention.

The bracket 35 includes a coupling portion 35D extending rightward from the coupling portion 35A, and other members not shown are fixed to an upper portion of the coupling portion 35D.

In this way, the EGR cooler 24 is fixed to the surge tank 45 by the bracket 35, and the bracket 35 connects the surge tank 45 and the cylinder head 12.

The coupling portion 35B is disposed in the vicinity of the downstream end 45B of the surge tank 45 in the bank direction, and the coupling portion 35C is disposed in the vicinity of the upstream end 45A of the surge tank 45 in the bank direction.

The holder 35 has an extension 35E extending below the exhaust gas intake portion 24B. In other words, the extension portion 35E of the bracket 35 is disposed between the exhaust gas intake portion 24B and the branch pipe 44.

In fig. 2 and 6, the EGR cooler 24 is positioned in the bank direction such that the exhaust gas intake portion 24B is located above the branch pipe 44.

According to the engine 1 of the present embodiment, the plurality of

branch pipes

41, 42, 43, 44 include the branch pipe 42 as a curved branch pipe that is curved such that the downstream end thereof is offset in the cylinder row direction to the side opposite to the side where the throttle valve body 23 is located with respect to the upstream end thereof. Further, the EGR cooler 24 is fixed to the intake manifold 40 at a position closer to the throttle valve body 23 than the branch pipe 42 in the bank direction.

The EGR valve 26 is disposed above the branch pipe 42 and fixed to an upper portion of the EGR pipe 31. The EGR pipe 31 extends along the upper surface of the branch pipe 42 toward the upper surface of the surge tank 45, and the EGR pipe 31 is connected to the upper surface of the branch pipe 42 and the upper surface of the surge tank 45 and is integrated with the branch pipe 42 and the surge tank 45.

In this way, the throttle valve body 23 is connected to the upstream end 45A of the surge tank 45 in the intake manifold 40, and the upstream end 45A of the surge tank 45 is offset to the side of the intake port 64 disposed at the end portion in the cylinder row direction among the plurality of

intake ports

61, 62, 63, 64.

Therefore, the branch pipe 42 is shaped such that its downstream end is offset in the bank direction to the side opposite to the side where the throttle valve body 23 is located with respect to its upstream end. Further, since the length of the branch pipe 42 is longer than the length of the

branch pipes

43 and 44, and the rigidity is low, vibration is likely to occur due to vibration of the engine 1.

Therefore, in the present embodiment, the EGR cooler 24 is fixed to at least one of the cylinder head 12 and the surge tank 45, and is fixed to the branch pipe 42 via the EGR valve 26 and the EGR pipe 31.

Therefore, the upstream end of the branch pipe 42 on the surge tank 45 side is connected to the surge tank 45 at a position closer to the throttle valve body 23 than the branch pipe 42 in the cylinder row direction via the upstream portion of the EGR pipe 31, the EGR valve 26, and the EGR cooler 24, and therefore vibration of the branch pipe 42 can be suppressed.

Further, the EGR pipe 31 extends from the upper portion of the branch pipe 42 bent in a protruding shape upward to the upper portion of the surge tank 45, is connected to the branch pipe 42 and the surge tank 45, and is integrated with the branch pipe 42 and the surge tank 45, so that the coupling rigidity of the branch pipe 42 to the surge tank 45 can be improved, and therefore, vibration of the branch pipe 42 can be suppressed.

As a result, even when the throttle valve body 23, which is an intake member attached to the upstream side of the intake manifold 40, is disposed in the vicinity of the exhaust gas intake portion 24B of the EGR cooler 24, the support rigidity of the intake manifold 40 and the EGR cooler 24 can be improved.

According to the engine 1 of the present embodiment, the EGR valve 26 has the EGR valve side flange portion 26A connected to the EGR pipe 31, and the EGR pipe side flange portion 31C extending upward and connected to the EGR valve side flange portion 26A is provided at the upper end of the EGR pipe 31.

Thus, the rigidity of the intake manifold 40 can be improved by connecting the EGR pipe side flange portion 31C having a large cross-sectional area to the branch pipe 42.

Further, since the EGR valve side flange portion 26A having a large cross-sectional area is attached to the EGR pipe side flange portion 31C, the EGR valve 26 can be firmly attached to and supported by a portion of the intake manifold 40 where rigidity is improved.

As a result, the support rigidity of the intake manifold 40 can be improved.

According to the engine 1 of the present embodiment, the intake manifold 40 has the outlet-side flange 48 that connects the

branch pipes

41, 42, 43, 44 to the

intake ports

61, 62, 63, 64, and the branch pipe 42 is formed with the connecting rib 46 that connects the upper surface of the branch pipe 42 and the outlet-side flange 48. The EGR pipe 31 is connected to the outlet-side flange 48 via the connecting rib 46.

Accordingly, the EGR pipe 31 and the outlet-side flange portion 48 are connected via the connecting rib 46, and therefore, the rigidity of the EGR pipe 31 can be increased, and the support rigidity of the intake manifold 40 can be increased.

According to the engine 1 of the present embodiment, the EGR cooler 24 is fixed to the surge tank 45 by the bracket 35, and the bracket 35 connects the surge tank 45 and the cylinder head 12.

In this way, the bracket 35 connects the cylinder head 12 having high rigidity to the surge tank 45, and the EGR cooler 24 is attached to the surge tank 45, so that the EGR cooler 24 is attached not only to the surge tank 45 but also to the cylinder head 12, and the support rigidity of the EGR cooler 24 can be improved.

While the embodiments of the present invention have been disclosed, it should be apparent that modifications and variations can be made by those skilled in the art without departing from the scope of the present invention. It is intended that all such modifications and equivalents be included in the claims of the present invention.

Claims

1. An engine for a vehicle, characterized by comprising:

a cylinder head having a plurality of intake ports arranged side by side in a cylinder row direction;

an intake manifold having a surge tank extending in the cylinder row direction and a plurality of branch pipes connecting the plurality of intake ports to the surge tank, respectively, in the order of arrangement in the cylinder row direction;

an intake member connected to an upstream end of the surge tank, the intake member adjusting an amount of air flowing into the surge tank;

an EGR cooler that is disposed above the intake manifold and through which exhaust gas passes in the bank direction;

an EGR valve connected to an exhaust gas outlet of the EGR cooler; and

an EGR tube that guides exhaust gas from the EGR valve to the surge tank,

an upstream end of the surge tank is disposed on one side of an outer intake port located at an end portion in the bank direction among the plurality of intake ports,

a downstream end of the surge tank is disposed on one side of an inner intake port located at a central portion in the cylinder row direction among the plurality of intake ports,

the plurality of branch pipes include at least one curved branch pipe curved such that a downstream end thereof is offset in the cylinder row direction with respect to an upstream end thereof to a side opposite to a side where the intake part is located,

the EGR cooler is fixed to the intake manifold at a position closer to the intake member than the bent branch pipe in the bank direction,

the EGR valve is disposed above the bent branch pipe and fixed to an upper portion of the EGR pipe,

the EGR pipe extends to the upper surface of the pressure stabilizing box along the upper surface of the bent branch pipe, is connected with the upper surface of the bent branch pipe and the upper surface of the pressure stabilizing box and is integrated with the bent branch pipe and the pressure stabilizing box.

2. The vehicle engine according to claim 1,

the EGR valve has an EGR-valve-side flange portion connected to the EGR pipe,

an EGR-pipe-side flange portion extending upward and connected to the EGR-valve-side flange portion is provided at an upper end of the EGR pipe.

3. The vehicular engine according to claim 1 or 2,

the intake manifold has a flange portion connecting the branch pipes to the intake ports, and the branch bent pipe has a connecting rib connecting an upper surface of the branch bent pipe and the flange portion,

the EGR pipe is coupled to the flange portion by the coupling rib.

4. The vehicular engine according to claim 1 or 2,

the EGR cooler is fixed to the surge tank by a bracket,

the support connects the surge tank with the cylinder cover.

5. The vehicle engine according to claim 3,

the EGR cooler is fixed to the surge tank by a bracket,

the support connects the surge tank with the cylinder cover.