JPH1047170A - Fitting structure of exhaust recirculation valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration of a resin by fixing a metallic tubular member having an inner hole to form an intake passage to a resin intake manifold, and providing a cooling water passage to circulate the cooling water in the tubular member to reduce the thermal effect by the exhaust gas on the resin intake manifold. SOLUTION: An exhaust recirculation part 20 provided between a throttle body 11 and a resin intake manifold is provided with a metallic tubular 21 having an inner hole 21a to form an intake passage, and an exhaust recirculation valve 12 is fixed to the tubular member 21. A pipe 30 to lead the exhaust gas from an exhaust manifold is fixed to the tubular member 21, and an exhaust inlet 22 to lead the exhaust gas from the pipe 30 to the exhaust recirculation valve 12 is formed. Cooling water passages 26, 27 are formed in the tubular member 21, and one end of the passage 26, 27 is communicated to a cooling water passage for heating the hot water of a throttle body 11. The tubular member 21 is cooled with the circulating cooling water in the passage 26, 27 to prevent heat transmission to the resin intake manifold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a structure for mounting an exhaust gas recirculation valve in an internal combustion engine.

[0002]

2. Description of the Related Art In recent years, in order to reduce the weight and the manufacturing cost of an intake manifold of an internal combustion engine cast from an aluminum alloy, an attempt has been made to adopt a resin intake manifold. However, since the exhaust gas recirculation valve has been generally directly attached to the intake manifold for the convenience of layout and simplification of the configuration, the intake manifold is made of resin (for example,
Assuming a nylon heat-resistant temperature of 130 °), a high-temperature exhaust (2
(300 ° to 300 °) may cause thermal deformation or melting of the mounting portion of the exhaust gas recirculation valve.

Therefore, a mounting structure of an exhaust gas recirculation valve in which an exhaust gas outlet is provided in an overlapped portion of the exhaust gas recirculation valve with a resin intake manifold and which has an annular groove surrounding an exhaust outlet and for recirculating a cooling medium such as intake air is conventionally known. It is proposed in Japanese Patent Laid-Open No. 63-164554.

[0004]

However, in the above-mentioned prior art, the mounting surface between the exhaust gas recirculation valve and the resin intake manifold is cooled by the cooling medium.
Since the exhaust gas to be introduced is difficult to be cooled, the exhaust gas may deteriorate the resin intake manifold.

Therefore, an object of the present invention is to reduce the thermal effect of exhaust of a resin intake manifold and prevent the resin from deteriorating.

[0006]

In order to solve the above-mentioned technical problems, the technical means taken in the present invention is that a metal cylindrical member having an inner hole forming an intake passage is connected to a resin intake manifold. Fixed, while fixing the exhaust gas recirculation valve so that the exhaust outlet opens in the inner hole of the cylindrical member,
A cooling water passage through which cooling water circulates is provided in the tubular member.

According to this, the exhaust gas introduced into the inner hole of the cylindrical member is cooled in the cylindrical member by the new intake air, and does not thermally affect the time when the exhaust gas enters the resin intake manifold. Become. Further, the cylindrical member is appropriately cooled by the cooling water, and the temperature of the manifold is prevented from becoming high due to heat conduction to the resin intake manifold via the cylindrical member.

Further, the cylindrical member has a fixing flange at a fixing portion with the resin intake manifold, and the fixing flange is formed with the annular cooling water passage surrounding the inner hole, so that the cylindrical member is interposed. High-temperature heat conduction to all the resin intake manifolds can be further prevented.

Also, if a cylindrical member is interposed between the intake manifold made of resin and the throttle body and cooling water for heating the hot water of the throttle body is circulated through the cooling water passage, the cooling water circulates. Can be simplified.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an exhaust gas recirculation valve mounting structure according to the present invention will be described below with reference to the drawings.
In FIG. 1, new intake air is introduced into a cylinder head of an internal combustion engine (not shown) via an intake hose 10, a throttle body 11, and a resin intake manifold 13. In the present embodiment, an exhaust gas recirculation unit 20 is provided between the throttle body 11 and the intake manifold 13 made of resin. In FIG. 1, reference numeral 12 denotes an exhaust gas recirculation valve, 13a denotes a surge tank, and 13b denotes a flange attached to a cylinder head (not shown).

FIG. 2 shows details of the exhaust gas recirculation unit 20. FIG.
, Between the throttle body 11 and the resin intake manifold 13, an inner hole 21 forming an intake passage is formed.
A metal tubular member 21 formed by casting or die-casting aluminum having a is interposed. FIG.
As shown in FIG. 1, the exhaust gas recirculation valve 12 is fixed to the cylindrical member 21, and the exhaust gas outlet 23 of the exhaust gas recirculation valve 12 is formed in the cylindrical member 21 so as to open to the inner hole 21 a.
Exhaust from an exhaust manifold (not shown) is provided in the tubular member 21 (in some cases, a cylinder head is interposed on the way).
Is fixed, and an exhaust introduction hole 22 that guides exhaust gas from the pipe 30 to the exhaust gas recirculation valve 12 is formed in the tubular member 21. The inner hole 2 is formed in the cylindrical member 21.
Cooling water passages 26 and 27 extending in the same direction as 1a are formed, and one ends of both passages are connected to a cooling water passage for heating hot water of the throttle body 11. As shown in FIGS. 2 and 4, the other end of each of the two passages 26 and 27 is formed at one end flange portion 24 of a tubular member 21 fixed to the resin intake manifold 13 so as to surround the inner hole 21a. It is open in the annular groove 28. The flange 13a of the resin intake manifold 13 fixed to the flange 24
In FIG. 1, O-rings 14a and 14b are fitted in the annular grooves located on the inner peripheral side and the outer peripheral side of the annular groove 28, and the fixing between the two flange portions is made liquid-tight. Further, between the other end flange portion 25 of the tubular member 21 and the flange portion 11a of the throttle body 11, a gasket 15 is similarly fixed in a liquid-tight manner.

In this embodiment having the above-described configuration, the exhaust gas recirculation valve 12 is opened, and the high-temperature exhaust gas is
When the exhaust gas is introduced into the inner hole 21 a from the throttle body 11, the exhaust gas impinges on the inner wall of the inner hole 21 a and diffuses, and is mixed with fresh intake air from the throttle body 11. For this reason, by the time the resin enters the intake manifold 13 made of resin, the exhaust gas is cooled to a temperature that does not thermally affect the resin.

Further, since the cylindrical member 21 to which the exhaust gas is directly applied is made of metal, it does not deteriorate due to the high temperature of the exhaust gas.

The tubular member 21 is provided with a cooling water passage 26,
While being properly cooled by the cooling water circulating through 27,
Flange part 2 between resin intake manifold 13
4 is cooled by cooling water passing through the annular groove 28, and high-temperature heat conduction to the resin intake manifold 13 through the flange portion 24 is prevented.

The present invention is not limited to the above-described embodiment, but can be appropriately modified within the scope of the claims. For example, the exhaust gas recirculation unit 20 may be configured to be attached to the surge tank 13 a of the resin intake manifold 13, and the cooling water to the tubular member 21 is not introduced from the throttle body 11, but is connected to the tubular member 21 by a pipe or the like. You may introduce using.

[0016]

As described above, according to the present invention, the exhaust gas introduced into the inner hole of the metal tubular member is cooled in the tubular member by new intake air, and the exhaust gas is cooled in the resin intake manifold. When it enters, it becomes thermally unaffected, and the tubular member is accurately cooled by the cooling water, and the temperature of the manifold becomes high due to heat conduction to the resin intake manifold via the tubular member. As it is prevented, the thermal effect of the exhaust of the resin intake manifold is reduced,
Deterioration of the resin can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic view of an embodiment of a mounting structure of an exhaust gas recirculation valve according to the present invention.

FIG. 2 is a detailed cross-sectional view of one embodiment of the mounting structure of the exhaust gas recirculation valve according to the present invention.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a view taken in the direction of arrow B in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Throttle body 12 Exhaust recirculation valve 13 Resin intake manifold 20 Exhaust recirculation part 21 Cylindrical member 23 Exhaust outlet 24 Flange part 26, 27 Cooling water passage 28 Annular groove

Claims (3)

[Claims] 1. A metal tubular member having an inner hole forming an intake passage is fixed to a resin intake manifold, and an exhaust gas recirculation valve is fixed so that an exhaust outlet is opened in the inner hole of the cylindrical member. And a cooling water passage for circulating cooling water in the tubular member. 2. The method according to claim 1, wherein the cylindrical member has a fixing flange at a fixing portion with the resin intake manifold, and the fixing flange is formed with the annular cooling water passage surrounding the inner hole. The mounting structure for an exhaust gas recirculation valve according to claim 1. 3. The cooling device according to claim 1, wherein the tubular member is interposed between the resin intake manifold and the throttle body, and cooling water for heating the throttle body with hot water is circulated through the cooling water passage. The mounting structure of the exhaust gas recirculation valve according to claim 2.