JPH0450416Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] The present invention relates to a cooling device for an internal combustion engine.

[Conventional technology]

Conventionally, a flange has been provided at the connection between two parts of an internal combustion engine, and a gasket has been provided between the two parts. Further, as described in Japanese Utility Model Application Publication No. 56-101445, a water jacket is provided in the exhaust manifold, and the water jacket is formed by an open wall and the open part is covered by a lid member. This disclosure discloses a cylinder head with a built-in exhaust manifold. Also, Utsukai Showa 57-
Publication No. 112030 discloses an example in which a cooling water passage is provided in the central partition of an exhaust manifold connected to a twin-entry turbocharger.

[Problem that the invention attempts to solve]

As described in the above-mentioned Japanese Utility Model Publication No. 57-112030, in order to provide a cooling water passage in the exhaust manifold, it is necessary to use a core during molding. It will be necessary to remove the core sand and plug the hole again. Therefore, as described in the above-mentioned Japanese Utility Model Publication No. 56-101445, it is convenient to form the water jacket as a groove opening on the surface of the exhaust manifold and cover the opening with a cover member. Something happens. When such a groove is provided on the flange end face of the flange portion, the open portion of the groove can be covered by the other opposing flange end face. Placing a gasket on the end face of this flange seems to ensure a perfect seal.

However, in this case, cooling water flows on one side of the gasket and does not flow on the other side of the gasket, resulting in a temperature difference on both sides of the gasket, causing deformation of the gasket and reducing its sealing ability. A problem occurs.

[Means for solving problems]

The cooling device for an internal combustion engine according to the present invention is provided with a cooling water passage consisting of an open groove on the flange end face of a flange portion forming an exhaust passage, and covering the opening of the groove to the flange end face with a metal plug, The present invention is characterized in that a gasket made of a metal plate is applied to the flange end face of the flange portion at a distance from the outer surface of the metal plug.

〔Example〕

FIG. 6 shows an example in which the present invention is applied to an internal combustion engine equipped with a twin-entry turbocharger 10, which includes an exhaust turbine 14 connected to an exhaust manifold 12 extending from the engine body, and an intake manifold ( (not shown). The exhaust manifold 12 has branch pipes 18 communicating with each cylinder, and a collecting pipe 20 that collects these branch pipes 18. A partition wall 22 is provided that extends in the central part of the collecting pipe 20 in the axial direction and divides the branch pipes 18 into two groups.
Two exhaust passages 12a and 12b are formed. These groups are divided to prevent exhaust interference between cylinders in each exhaust passage 12a, 12b.

Exhaust manifold 12 and turbocharger 1
The connecting ends of 0 are provided with flange portions 24 and 2, respectively.
6 is formed and is adapted to be connected by, for example, a bolt or the like. The exhaust turbine 14 of the turbocharger 10 corresponds to the two exhaust passages 12a and 12b of the collecting pipe 20 of the exhaust manifold 12.
Two exhaust passages 14a and 14b are also formed,
These extend into spiral scroll passages and open towards the turbine wheel.

FIG. 2 is a diagram showing a flange end surface 24a of the flange portion 24 at the tip of the collecting pipe 20 of the exhaust manifold 12. FIG. Figure 1 shows this flange end face 24a.
FIG. This flange portion 24 has the above-mentioned exhaust passages 12a and 1.
2b are formed side by side. A substantially figure-eight groove 28 is formed in the flange portion 24 so as to surround the exhaust passages 12a, 12b. This groove 2
8 is open to the flange end face 24a, and is formed on three sides by a bottom wall 28a and a side wall 28b. Therefore, in molding the exhaust manifold 12, there is no need to use a core to form the grooves 28, and a simple mold can be used.

As shown in FIG. 1, the groove 28 has a substantially constant depth along its entire circumference, and lateral holes 30, 32 of diameter slightly smaller than the depth of the groove 28 are laterally formed in the flange portion 24. It is formed. Side hole 30,
32 can each be fitted with a union 34, 36, whereby cooling water is supplied from one union 34 and discharged from the other union 34 through the cooling water passage formed by the groove 28. can do. Further, the groove 28 has a substantially constant width along its entire circumference, and steps 28c are provided on the side wall 28b at appropriate positions. Step 28
The upper side of c is wide and the lower side is narrower.

As shown in FIG. 1, a metal plug 38 is fitted into the groove 28. The metal plug 38 is formed of a plate material having a U-shaped cross section as shown in FIG. 1, and has the same contour as the surface contour of the groove 28 as shown in FIG. 3. however,
The width of the metal plug 38 is slightly larger than the width of the groove 28, and when it is fitted into the groove 28, it undergoes slight elastic deformation and is frictionally supported by the side wall 28b of the groove. Further, the inner bottom surface of the metal plug 38 is
At point c, the insertion position of the metal plug 38 is restricted. In this restrained position, the upper ends of the metal plug 38 on both side walls of the U shape are slightly sunken below the flange end surface 24a. Therefore, metal plug 3
The substantially horizontal wall surface between the two side walls of the U-shape, which is the outer surface of the flange 8, is also sunk below the flange end surface 24a.

A gasket 40 is applied to the flange end face 24a of the flange portion 24. As shown in FIG. 4, the gasket 40 has the same surface as the flange end surface 24a, and of course, the exhaust passage 12a,
It has passage holes 40a and 40b corresponding to 12b. This gasket 40 is made of a metal plate as shown in FIGS. 4 and 5. A raised bead 42 having the same outline as the figure-eight groove 28 is formed on the surface of the gasket 40.
On the back side of the gasket 40, raised beads 44, 46 are formed with the same outline as the figure-eight groove 28. These beads 44 and 46 are formed in two rows on both sides of the surface bead 42 so as to sandwich it, and the distance between the two rows is slightly wider than the width of the groove 28. Therefore, when the gasket 40 is applied to the flange end surface 24a, the two beads 44, 46 come into contact with the flange end wall outside the groove. Thus, after applying the gasket 40 to the flange end surface 24a of the flange portion 24, the two beads 44, 46
Gasket 40 may be secured to flange portion 24 by projection welding at . Also, using the bead 42 on the surface of the gasket 40, the gasket 40 can be attached to the turbocharger 10.
Can be welded to the projector.

Here, in the groove 28, a cooling water passage is formed on the inner surface of the metal plug 38, and an air holding space is formed between the outer surface of the metal plug 38 and the inner surface of the gasket 40. The air in this air holding space acts as a heat insulating layer, and since the cooling water does not come into direct contact with the gasket 40, a steep temperature gradient does not occur within the metal plate gasket 40, which is effective in extending the life of the gasket 40. Similarly, the temperature gradient of the metal plug 38 is also small and the sealing ability can be enhanced. Further, even if the air in the air holding space expands upon receiving heat from the turbocharger side, the expansion acts to press the metal plug 38 against the side wall 28b of the groove 28 and strengthen the sealing force of the metal plug 38. Further, by providing the cooling water passage at the end face of the flange of the exhaust manifold in this manner, the heat transferred to the housing of the turbocharger can be reduced, and the thermal load applied to the turbocharger can be reduced.

[Effect of idea]

As explained above, according to the present invention, the thermal load on the flange surface can be reduced, the durability against distortion and cracking can be increased, and exhaust gas leakage can be prevented.
Furthermore, sealing performance can be enhanced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view taken along the line - in FIG. 2 showing a cooling device for an internal combustion engine according to the present invention, FIG. 2 is an end view of the flange portion of the exhaust manifold according to the present invention, and FIG. A plan view showing the metal plug; FIG. 4 is a plan view showing the gasket in FIG. 1;
5 is a sectional view taken along the gasket line - of FIG. 4, and FIG. 6 is a sectional view showing the turbocharger and exhaust manifold according to the present invention. 24...Flange portion, 24a...Flange end surface, 12a, 12b...Exhaust passage, 28...Groove,
38...metal plug, 40...gasket.

Claims (1)

[Scope of utility model registration request] A cooling water passage consisting of an open groove is provided in the flange end face of the flange portion forming the exhaust passage, and the opening of the groove to the flange end face is covered with a metal plug, and a space is left between the outer surface of the metal plug and the opening of the groove to the flange end face. A cooling device for an internal combustion engine, characterized in that a gasket made of a metal plate is applied to the flange end face of the flange portion.