DE29518189U1 - Exhaust manifold system - Google Patents

Description

Applicant: Priority:

Mr DE 195 03 462.7-13

Rudolf LOUp from 03.02.1995

Hauweg 18

73655 Pluederhausen

2627 001/2 S/Sch 15.11.1995

WP95/7

Title: Exhaust manifold system

DESCRIPTION

The invention relates to an exhaust manifold system with an exhaust pipe that can be connected to one or more exhaust ports of a cylinder head, wherein the exhaust pipe is designed as a one- or multi-part inner pipe group and is surrounded by a capsule, and there is an air gap between the capsule and the inner pipe group.

Exhaust manifolds are known in many different designs. Insulated exhaust manifolds are also known, especially in vehicles in the higher price category. Although the technical advantages of insulated exhaust manifolds would also help the middle and lower vehicle classes as well as commercial vehicles of all categories to achieve a higher degree of environmental friendliness, their regular use has so far failed due to the high manufacturing costs and the associated

associated costs. Due to the load-bearing function, in particular the connection of further exhaust pipes, catalytic converters, etc., the flanges and insulation bodies of these exhaust manifolds must be dimensioned accordingly, which in turn has an adverse effect on the overall weight. The insulators must be designed in such a way that thermal expansion can be compensated. In addition, the exhaust manifolds must be designed in such a way that they are gas-tight so that exhaust gases cannot escape and outside air cannot penetrate in order to avoid damaging the catalytic converter.

DE 42 26 171 A1 discloses an exhaust manifold in which a first part, which carries the exhaust gases, is surrounded by a second part of the manifold. The two parts are welded together after they have been manufactured so that they can only be handled together. It is not possible to replace individual components made of different materials.

DE-OS 22 42 857 discloses an exhaust gas guidance system and DE-U-93 14 690 discloses a device for fastening a gas guide channel in an exhaust gas line, but these do not represent the state of the art in this category.

The invention is therefore based on the object of providing an exhaust manifold system which has a low weight, low heat radiation and low

noise emission, which reduces the response time of the catalyst and which is also cost-effective to produce.

This object is achieved according to the invention in that the inner pipe group and/or the exhaust pipe and the capsule form a split exhaust manifold system and are independently replaceable from one another.

The division of the exhaust manifold system into an inner pipe group and a capsule has the significant advantage that the materials of the individual components can be specifically adapted to their respective functions, that the individual components can be replaced independently of one another if necessary, that the air gap between the inner pipe group and the capsule provides optimal thermal insulation, which reduces the response time of the catalyst. In addition, the two-part structure reduces the overall weight, as thin-walled components can be used. Another advantage is that the heat radiation from the capsule is significantly reduced, as it is insulated from the hot inner pipe group by an air gap. In addition, noise emissions are significantly reduced by physically separating the inner pipe group and the capsule.

Further advantages, features and details emerge from the subclaims and the following description, in which particularly preferred embodiments are explained in detail with reference to the drawing. Showing:

Figure 1 shows a first embodiment of an exhaust manifold system with an inner pipe group and a capsule enclosing the latter, with the capsule being placed on the cylinder head?

Figure la shows a further embodiment of an exhaust manifold system, wherein the cylinder head forms a part of the capsule and this part is closed by a cover;

Figure 2 shows an inner pipe group made up of several pipe sections;

Figure 3 shows an inner tube group of Figure 2 with a capsule arranged above it according to Figure 1; and

Figure 4 shows an inner tube group according to Figure 2 with capsules arranged above it (Figure la).

In Figure 2, a cylinder head 1 is shown which is provided with three exhaust ports 3.

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These outlet channels 3 are closed by a total of 4
designated inner tube group, which the outlet channels 3
exhaust gases leaving the system and are then sent to a further
exhaust system (17, Figure 3). The inner pipe group 4 consists of Figure 2, which is merely a preferred
embodiment and not restrictive
consists of three thin-walled pipe sections 2a, 2b and 2c. These pipe sections 2a - 2c are each separately connected to the cylinder head 1 via flanges 2d. Instead of several flanges 2d, a single flange can also be used, as in
Figure 2 shows the individual pipe sections 2a - 2c connecting to the cylinder head l. One or the
several flanges 2d are pushed over the ends of the pipe sections 2a - 2c facing the cylinder head 1 and connected to it by welding, soldering, clipping, expanding, flanging or
such as are indelibly connected.

The other facing free ends of the
Pipe sections 2a - 2c are connected via a sliding seat 7
connected to each other, which advantageously reduces thermal stresses
avoided and thermal expansion in the individual pipe sections can be compensated.

The inner tube group 4 is, as shown for example in Figures 1
and 3, surrounded by a capsule 15 gas-tight, which
is also connected to the cylinder head 1. For this purpose, the capsule 15 has feet 10, which are connected to the

The outer side of the cylinder head 1 can be screwed or similarly connected to it. Between the inner pipe group 4 and the capsule 15 there is an air gap 14 which has a sound and heat insulating effect. On the side facing the further exhaust system 17, the capsule 15 is provided with a flange 11 via which the further exhaust system 17 can be coupled. This exhaust system 17 is connected to the free end of the pipe section 2a of the inner pipe group 4 via a sliding seat 8. In this way, thermal stresses are also avoided and thermal expansions are compensated.

From Figures 1 and 3 it can also be seen that the capsule 15 is made up of two shell walls 3a and 3b. These walls 3a and 3b form a cavity 9 in which a cooling medium, for example cooling water from the engine's cooling circuit, flows. This cavity 9 is connected via connecting lines 3c to another cavity 9 of another capsule 15 or to supply lines.

In another embodiment, the capsule 15 is partially molded onto the cylinder head 1 in the form of webs 16, which can be clearly seen in Figures 1a and 4. These webs 16 essentially form the part of the capsule 15 that accommodates the inner tube group 4. The free end of the webs 16 is closed by a cover 13, which closes off the interior space 14. Here, too,

the cover 13 consists of two shell walls 5a and 5b, which form a cavity 9 that accommodates the cooling medium. This cavity 9 is connected to the cooling circuit of the engine via channels 12 that are located in the webs 16.

Since the air gap 14 is enclosed in a gas-tight manner in the capsule 15, exhaust gases cannot escape into the open air. In addition, the pipe sections 2a - 2c of the inner pipe group 4, which usually has a high temperature, are optimally thermally insulated. The air gap 14 and the water jacket in the cavity 9 and the channels 12 also ensure optimal noise insulation. If necessary, individual components of the assemblies can be replaced.

Claims (20)

PROTECTION CLAIMS 1. Exhaust manifold system with an exhaust pipe connectable to one or more exhaust ports (3) of a cylinder head (l), wherein the exhaust pipe is designed as a one-part or multi-part inner pipe group (4) and is surrounded by a capsule (15) and there is an air gap (14) between the capsule (15) and the inner pipe group (4), characterized in that the inner pipe group (4) and/or the exhaust pipe and the capsule (15) form a split exhaust manifold system and are replaceable independently of one another. 2. Exhaust manifold system according to claim 1, characterized in that the inner pipe group (4) consists of one or more thin-walled pipe sections (2a - 2c). 3. Exhaust manifold system according to claim 2, characterized in that the pipe sections (2a - 2c) are connected to one another via a sliding seat (7) or a plug connection. 4. Exhaust manifold system according to claim 2 or 3, characterized in that each pipe section (2a - 2c) is connected to a respective outlet channel (3) of the cylinder head (1) via a flange (2d). 5. Exhaust manifold system according to claim 4, characterized in that the pipe sections (2a - 2c) are connected to the flange or flanges (2d) by welding, soldering, clipping, plugging or the like. 6. Exhaust manifold system according to one of the preceding claims, characterized in that the inner pipe group (4) consists of thin-walled pipes, sheets, strips, IHV parts or the like. 7. Exhaust manifold system according to one of claims 2 to 6, characterized in that the pipe sections (2a - 2c) are made in one or more parts, for example from half shells, and are produced by welding, soldering, folding, flanging, clinching or a combination thereof. 8. Exhaust manifold system according to one of claims 2 to 7, characterized in that the pipe sections (2a - 2c) are designed as Y-connectors, T-pieces, angle pieces or the like. 9. Exhaust manifold system according to one of the preceding claims, characterized in that the inner pipe group (4) is connected to the further exhaust system (17) via a sliding seat (8). 10. Exhaust manifold system according to one of the preceding claims, characterized in that the capsule (15) consists of one or more shells. 11. Exhaust manifold system according to claim 10, characterized in that the shell is double-walled. 12. Exhaust manifold system according to claim 11, characterized in that the cavity (9) between the two shell walls (3a and 3b or 5a and 5b) contains a cooling medium. 13. Exhaust manifold system according to claim 12, characterized in that the cooling medium is connected to the cooling circuit of the engine. 14. Exhaust manifold system according to one of claims 11 to 13, characterized in that the shell walls (3a and 3b or 5a and 5b) are connected to one another in a fluid-tight manner by welding, soldering, gluing or the like. 15. Exhaust manifold system according to one of the preceding claims, characterized in that the capsule (15) is tightly connected to the cylinder head (1). 16. Exhaust manifold system according to one of the preceding claims, characterized in that the capsule (15) seals the air gap (14) between the inner pipe group (4) and capsule (15) in a fluid-tight manner. 17. Exhaust manifold system according to one of the preceding claims, characterized in that the capsule (15) is designed to accommodate further exhaust pipes (17), silencers, catalysts and the like. 18. Exhaust manifold system according to one of the preceding claims, characterized in that the capsule (15) is partially formed in one piece on the cylinder head (1). 19. Exhaust manifold system according to claim 18, characterized in that the capsule (15) is sealed gas-tight by a cover (13). 20. Exhaust manifold system according to one of the preceding claims, characterized in that the capsule (15) is directly connected to the cooling system of the cylinder head (1).