JPH11198663A - Cooling device for exhaust manifold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling device of exhaust manifold which can cool the exhaust manifold efficiently even while a vehicle such as an automobile is stopping. SOLUTION: A baffle member 25 provided with the first and second baffle plates 29, 30 is provided at the upper side of an engine 13 disposed in the engine room 12 of an automobile 11. A radiator 30 for cooling the cooling water of the engine 13 is provided at the front side of the engine 13, and air is sucked from the front side of he radiator 20 by driving the cooling fan 23 of the radiator 20. The air is passed through the radiator 20, guided as cooling wind to above an exhaust manifold 14 by the first baffle plate 29, and guided down toward the manifold 14 by the second baffle plate 30. The exhaust manifold 14 is exposed to the cooling wind generated by driving the cooling fan 23, and cooled by its cooling wind.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling system for an exhaust manifold for cooling an exhaust manifold located on the rear side of an engine in an engine room of the vehicle.

[0002]

2. Description of the Related Art In an engine provided in an engine room of an automobile, an exhaust manifold may be located at a rear side of the automobile. In this case, even if wind enters the engine room from the front of the car when the car is running,
Since the wind is blocked by the engine and hardly hits the exhaust manifold, it is difficult to cool the exhaust manifold. Therefore, conventionally, various devices for improving the cooling performance of such an exhaust manifold have been proposed, and for example, an exhaust manifold cooling device described in Japanese Utility Model Laid-Open No. 3-88922 is known.

The cooling device described in the publication has a duct formed in an engine hood of an automobile. The duct opens at the front side of the vehicle and extends rearward of the vehicle along the engine hood. Then, as the automobile runs, the cooling air enters the duct, and the cooling air is applied to the exhaust manifold via the duct. By cooling the exhaust manifold with such a cooling device, it is possible to prevent the cooling performance of the exhaust manifold from lowering even when the exhaust manifold is located on the rear side of the vehicle with respect to the engine.

[0004]

By the way, in the above-mentioned conventional cooling device, when the automobile is stopped, cooling air does not enter the duct of the device. For this reason, when the running automobile stops at a traffic light or the like, the cooling air does not hit the exhaust manifold. As a result, the exhaust air is not cooled by the cooling air, so that the exhaust manifold becomes excessively high temperature, and the heat reduces the durability of the exhaust manifold.

The present invention has been made in view of such circumstances, and has as its object to cool an exhaust manifold that can efficiently cool the exhaust manifold even when a vehicle such as an automobile is stopped. It is to provide a device.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, cooling air is guided from the front to the rear of the engine in an engine room of the vehicle, and the cooling air is used by the cooling air. An exhaust manifold cooling device that cools an exhaust manifold disposed behind the engine, wherein a cooling air generated by a cooling fan of a radiator provided in the engine room is guided to the rear of the engine via an upper portion of the engine. A first air guiding means, and a second air guiding means for guiding cooling air passing above the engine downward behind the engine.

According to this configuration, even when the vehicle is stopped, the cooling air generated by the cooling fan of the radiator is
The air is guided to above the exhaust manifold by the first air guide, and is guided from above to below the exhaust manifold by the second air guide. Therefore, the cooling air is applied to the exhaust manifold even while the vehicle is stopped, and the cooling air cools the manifold.

[0008] The invention according to claim 2, further comprising a guide member for guiding cooling air generated by the cooling fan to the first air guide means.

According to this configuration, the guide member can prevent the cooling air generated by the cooling fan from flowing away from the first air guide means.
The cooling air can be more efficiently applied to the exhaust manifold to efficiently cool the same.

According to the third aspect of the present invention, the first air guide means includes a wind guide plate extending in a front-rear direction above the engine to suppress the diffusion of the cooling air in a lateral direction. 3. The cooling device for an exhaust manifold according to claim 1, wherein the cooling device is provided with a pair corresponding to the width.

With this configuration, the cooling air can be efficiently applied to the entire width of the exhaust manifold.
The exhaust manifold cooling device according to claim 3, wherein a clearance between a lower side of the air guide plate and an upper surface of the engine has a minimum size that allows vibration of the engine.

[0012] According to this configuration, of the cooling air flowing toward the exhaust manifold, the amount of the cooling air leaking from the gap between the air guide plate and the engine can be minimized, so that the cooling air is efficiently applied to the exhaust manifold. Will be able to do it.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, an engine 13 is provided in an engine room 12 of an automobile 11.
Are arranged. An exhaust manifold 14 extending downward is fixed to a rear side surface of the engine 13. Also,
A heat shield plate 15 is provided between the rear side surface of the manifold 14 and the rear inner wall surface of the engine room 12, similarly to the rear surface of the engine 13. This heat shield plate 1
5, a brake hose 16 and a power steering hose 1 extending along the rear inner surface of the engine room 12
The transfer of heat from the exhaust manifold 14 to the exhaust manifold 7 is suppressed.

The upper side of the engine room 12 is closed by an engine hood 18. In the engine room 12, an air inlet 19 for taking in outside air into the room 12 is provided on the front side, and a cooling water for cooling the engine 13 is provided on the rear side of the air inlet 19. A radiator 20 is provided.
The upper surface of the radiator 20 is in contact with a seal member 22 attached to the lower surface of the engine hood 18 via a bracket 21. The engine room 12 is partitioned into a space on the air intake side and a space on the engine 13 side by the radiator 20, the bracket 21, and the seal member 22. Therefore, the air taken into the engine room 12 from the air intake 19 passes through the radiator 20 and flows into the space on the engine 13 side.

On the rear surface of the radiator 20, a pair of cooling fans (only one is shown in FIG. 1) 23 for sucking air in front of the radiator 20 to the rear side is provided. When the air sucked by the driving of the cooling fan 23 passes through the radiator 20, heat exchange is performed between the cooling water flowing inside the radiator 20 and the air. This heat exchange cools the cooling water. In the present embodiment, one fan 2
3 and the upper side of the engine 13, the radiator 20
A guide member 24 and an air guide member 25 for guiding the air passing through the cooling fan 23 to the exhaust manifold 14 located on the rear side of the engine 13 as cooling air are provided.

Here, the structure of the guide member 24 is shown in FIG.
FIG. 2 is a plan sectional view of the engine room 12. As shown in the figure, the guide member 24 is formed in a box shape,
A hole 26 is provided in the outer wall 24 a of the member 24 on the side of the wind guide member 25. In the engine room 12, an air cleaner 27 and a battery 28 are provided behind the guide member 24. The air passing through the radiator 20 is guided by the guide member 24 to the air cleaner 2.
7 and the battery 28 are prevented from being sent to the wind guide member 25 through the hole 26 of the guide member 24.

Next, the detailed structure of the wind guide member 25 is shown in FIG.
It will be described based on. As shown in FIG.
Is a substrate 25a formed in a square shape, a pair of first air guide plates 29 provided on the lower surface of the substrate 25a, and a substrate 25a.
and a second air guide plate 30 provided between the first air guide plates 29 on the rear side of the a. First air guide plate 2
Reference numerals 9 are fixed to the lower surface of the substrate 25a so as to be parallel to each other. The lower surface of the first air guide plate 29 is provided with a concave portion 29a that is curved in the longitudinal direction at the center in the longitudinal direction as shown in FIG. In addition, the second air guide plate 30
The first air guide plate 29 has a curved shape so as to be located between the rear end portions thereof, so that the distance between the first air guide plate 29 and the substrate 25a increases toward the rear.

As shown in FIG. 1, the wind guide member 25 is attached to the lower surface of the engine hood 18 located above the engine 13 with the first wind guide plate 29 extending in the front-rear direction of the automobile 11. . When the air guide member 25 is attached to the engine hood 18, a gap 31 is formed between the recess 13 a of the first air guide plate 29 and the engine 13. In the present embodiment, the gap 31
Is set to a minimum value that allows the behavior (vibration) of the engine 13 when the engine 13 swings in the front-rear direction while the automobile 11 is running.

The air guide member 2 to the engine hood 18
5, the lower end of the second baffle plate 30 is
As shown in FIG. 1 in a state where the engine hood 18 is closed, the air guide plate 29 and the heat shield plate are adjusted so as to correspond to the upper end of the heat shield plate 15 fixed to the heat shield plate 3. The plate 15 is connected. Further, as shown in FIG. 2, the distance between the pair of first air guide plates 29 is set to a distance corresponding to the entire width of the exhaust manifold 14.

Next, the operation of the cooling device according to this embodiment will be described. The air that has entered from the air intake 19 due to the running of the automobile 11 or the driving of the cooling fan 23 is sent as cooling air to the engine room 12 on the engine 13 side after passing through the radiator 20. Of the pair of cooling fans 23 shown in FIG. 2, the cooling fan 23 located on the lower side in the figure
Is guided between the pair of first air guide plates 29 of the air guide member 25 through the holes 26 while being prevented from being sent to the air cleaner 27 and the battery 28 by the guide member 24. . The air that has passed through the other cooling fan 23 is sent directly as cooling air between the pair of air guide plates 29. Thus, the cooling air flows between the pair of air guide plates 29 from the front side to the rear side of the automobile 11, and is guided along the air guide plates 29 to above the exhaust manifold 14. At this time, the pair of baffle plates 2
9 and the cooling air flowing between the
The leakage to the outside via the gap 31 between the first and third members is minimized. This is because the gap 31 has a minimum size that allows the engine 13 to swing back and forth. Further, since the distance between the pair of air guide plates 29 is substantially equal to the lateral width of the exhaust manifold 14, the cooling air between the air guide plates 29 efficiently flows from the front side to the rear side of the automobile 11.

The cooling air guided to the upper side of the exhaust manifold 14 by the first air guide plate 29 is supplied to the second air guide plate 30 of the air guide member 25 and the heat shield plate 15 fixed to the engine 13. And the exhaust manifold 14
Is guided downward from above. As a result, cooling air is efficiently applied to the exhaust manifold 14 over the entire horizontal width, and the cooling air is
4 is cooled. Therefore, even when the automobile 11 is stopped, the exhaust manifold 14 is efficiently cooled by the cooling air generated by driving the cooling fan 23, and it is possible to suppress a decrease in the cooling performance of the manifold 14.

Further, the cooling air after cooling the exhaust manifold 14 does not flow forward of the radiator 20 in the engine room 12. This is because the engine room 12 is composed of the radiator 20, the bracket 21, and the sealing material 2.
This is because it is divided by two. Therefore, the cooling air (air) heated by the exhaust manifold 14 circulates in front of the radiator 20 and is used again as cooling air for the exhaust manifold 14.
The cooling performance of No. 4 does not decrease.

Note that the cooling device of the present embodiment is
It has been confirmed by experiments of the inventors that the surface temperature of the exhaust manifold 14 becomes lower than usual by 120 to 130 ° C. when the vehicle is driven at a high speed or when climbing a hill.

As described in detail above, according to this embodiment, the following effects can be obtained. Cooling air generated by driving the cooling fan 23 is guided to above the exhaust manifold 14, and further guided downward by the second baffle plate 30 and the heat shield plate 15. Therefore, even when the vehicle 11 is stopped, the exhaust manifold 14 is efficiently cooled, and the exhaust manifold 14 is cooled.
Can be prevented from lowering in heat resistance due to the lowering of the cooling performance.

The first baffle plate 29 in the baffle member 25
31 is set to a minimum size that allows the engine 13 to swing in the front-rear direction, so that leakage of cooling air from the gap 31 is minimized. Therefore, the cooling air is efficiently applied to the exhaust manifold 14, and the cooling of the manifold 14 can be performed efficiently.

In the present embodiment, the distance between the pair of air guide plates 29 is a distance corresponding to the width of the exhaust manifold 14. Therefore, the cooling air can efficiently flow between the air guide plates 29, and the cooling air can be blown over the entire width of the exhaust manifold 14, so that the manifold 14 can be efficiently cooled.

The cooling air from the cooling fan 23 is guided by the guide member 24 toward the pair of air guide plates 29, and the cooling air is prevented from flowing away from the air guide member 25. The manifold 14 can be efficiently cooled by efficiently applying the cooling air to the manifold 14.

The engine room 12 includes the radiator 2
The cooling air after cooling the exhaust manifold 14 does not flow in front of the radiator 20 because it is partitioned by the brackets 0, the brackets 21, and the seal members 22. Therefore, the cooling performance of the exhaust manifold 14 does not decrease, for example, the cooling air (air) heated by the exhaust manifold 14 is used again as the cooling air of the exhaust manifold 14.

The present embodiment can be modified, for example, as follows. In the cooling device of the present embodiment, the wind guide member 25 including the first and second wind guide plates 29 and 30 is attached to the engine hood 18, but instead of the first and second wind guide plates 29 and 30. The air guide plates 29, 30 may be formed integrally with the lower surface of the engine hood 18.

The structure of the cooling device according to the present embodiment may be simplified by omitting the guide member 24. In the present embodiment, the pair of first baffle plates 29 in the baffle member 25 are made parallel to each other. Instead, the two baffle plates 29 move closer to each other toward the rear side of the automobile 11. May be. In this case, since the flow velocity of the cooling air flowing between the pair of air guide plates 29 becomes faster as approaching the exhaust manifold 14, the cooling air is efficiently applied to the exhaust manifold 14 to efficiently cool the manifold 14. Can be. Even in the case of such a configuration, it is preferable that the distance between the rear end portions between the first air guide plates 29 is substantially equal to the width of the exhaust manifold 14.

In this embodiment, the pair of first air guide plates 2
Although the distance between the first air guide plates 29 is set to a value substantially equal to the width of the exhaust manifold 14, the distance between the first air guide plates 29 may be changed as appropriate. For example, the distance between both first air guide plates 29 may be set according to the width of engine 13.

The number of the first air guide plates 29 may be appropriately changed. Next, technical ideas other than the claims that can be grasped from the above embodiments are described below together with their effects.

(1) The exhaust manifold cooling device according to claim 1, wherein the first air guide means includes an air guide plate provided on an upper side of the engine so as to extend in the front-rear direction. The clearance between the lower side of the engine and the upper surface of the engine is a minimum size that allows the engine to vibrate.

According to this configuration, of the cooling air flowing toward the exhaust manifold, the amount of the cooling air leaking from the gap between the air guide plate and the engine can be minimized. Therefore, the cooling air can be efficiently applied to the exhaust manifold to efficiently cool the exhaust manifold.

(2) The exhaust manifold cooling device according to claim 3 or 4, wherein the pair of air guide plates are closer to each other toward the rear of the engine.

According to this configuration, the flow velocity of the cooling air increases as the cooling air approaches the exhaust manifold. Therefore, the cooling air is efficiently applied to the exhaust manifold, and the cooling of the manifold can be performed efficiently. become able to.

[0037]

According to the first aspect of the present invention, the cooling air generated by the cooling fan of the radiator is guided to the upper portion of the exhaust manifold by the first air guiding means even when the vehicle is stopped. The second air guide means guides the exhaust manifold from above to below. Therefore, the cooling air is applied to the exhaust manifold even while the automobile is stopped, and the cooling air can cool the manifold.

According to the second aspect of the present invention, it is possible to prevent the cooling air generated by the cooling fan from flowing in the direction away from the first air guide means by the guide member, so that the exhaust manifold can be further improved. The manifold can be efficiently cooled by efficiently applying cooling air.

According to the third aspect of the present invention, since the cooling air is efficiently applied to the entire width of the exhaust manifold, the manifold can be efficiently cooled. According to the fourth aspect of the present invention, of the cooling air flowing toward the exhaust manifold, the amount of the cooling air leaking from the gap between the air guide plate and the engine can be minimized. Therefore, the cooling air can be efficiently applied to the exhaust manifold, and the exhaust manifold can be efficiently cooled.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an engine room structure of an automobile to which a cooling device according to an embodiment is applied.

FIG. 2 is a plan sectional view showing a plane structure of the engine room.

FIG. 3 is a cutaway perspective view showing the structure of a wind guide member.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 ... Car, 12 ... Engine room, 13 ... Engine, 14 ... Exhaust manifold, 15 ... Heat shield plate, 24 ... Guide member, 25 ... Wind guide member, 29 ... First wind guide plate, 30 ...
Second air guide plate.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideki Ito 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Toshiyoshi Suzaki 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation ( 72) Inventor Kazuta Abo 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (4)

[Claims] An exhaust manifold cooling device for guiding cooling air from the front to the rear of an engine in an engine room of a vehicle and cooling the exhaust manifold disposed behind the engine by the cooling air, First air guide means for guiding cooling air generated by a cooling fan of a radiator provided in the engine room to the rear of the engine via the upper part of the engine; And a second air guiding means for guiding the rear of the exhaust manifold downward, and a cooling device for the exhaust manifold. 2. The exhaust manifold cooling device according to claim 1, further comprising a guide member for guiding cooling air generated by said cooling fan to said first air guide means. Cooling system. 3. The first air guide means includes a pair of air guide plates extending above and below the engine in a front-rear direction to suppress the diffusion of the cooling air in a lateral direction in accordance with a lateral width of the exhaust manifold. The cooling device for an exhaust manifold according to claim 1, wherein the cooling device is configured as follows. 4. A cooling apparatus for an exhaust manifold according to claim 3, wherein a clearance between a lower side of said baffle plate and an upper surface of said engine has a minimum size capable of allowing vibration of said engine.