DE19818390A1 - Exhaust gas manifold for internal combustion engine - Google Patents

Abstract

The manifold (1) has an input flange (4-7) for an exhaust gas tube (8-11) for fixing to each cylinder of the cylinder bank, with a common output flange (12, 13). The manifold has at least two separately made manifold parts (2, 3). The input flanges are connected to the output tubes and to the common output flange to form a complete part of the manifold.

Description

The invention relates to an exhaust manifold for an internal combustion engine Machine according to the preamble of claim 1.

DE 1 95 11 514 C1 describes a multi-cylinder internal combustion engine apparently known, the two cylinder banks, each with three cylinders who has. The three cylinders of a cylinder bank are on one NEN common exhaust manifold connected, one each Inlet flange at the outlet of each cylinder with one drawn arranged exhaust pipe and an outlet flange. The one first and the second cylinder associated exhaust pipes open first in a common, transverse pipe section and are fed to the outlet flange in the further course the further exhaust system connects. The exhaust pipe of the third cylinder opens directly into the outlet flange.

Because of the limited space on the cylinder bank the assembly effort for the inlet flange on the middle cylinder which increases because the screws of this flange cross from that lying pipe section are covered and only with special tool can be tightened. This problem is compounded for cylinder banks with four or more cylinders in a row, since the input flanges on all middle cylinders only with increased effort on the cylinder head of the internal combustion engine can be adjusted.

The invention is based on the problem, the assembly friend Possibility of an exhaust manifold on a cylinder bank with at least to improve at least four cylinders in line.

This problem is solved according to the invention with the features of the Proverb 1 solved.

By dividing the exhaust manifold into at least two sepa advice trained manifold parts, the exhaust manifold in several successive assembly steps attached to the cylinder head become. The manifold parts, each at least two input flanges, the exhaust pipes assigned to the input flanges and egg an outlet flange into which the exhaust pipes open, can be assembled one after the other without mutual hindrance the.

The two outer cylinders of a cylinder bank are useful a manifold and the middle cylinders of a cylinder bank assigned at least one further manifold part. With a Zy Bench with four cylinders is the first and the first fourth cylinder a common manifold and the second and a third manifold assigned a common manifold. This version takes into account the firing order of the cylinders around in the exhaust pipes inside a manifold part to achieve the same pressure conditions and pressure gradients in the Exhaust gas that impair a defined flow direction can avoid.

For cylinder banks with a larger number of cylinders per cylinder derbank it is advantageous to have more than one manifold assign two cylinders. In particular, all middle ones Cylinder connected to a single manifold where is limited to two by the number of manifold parts and the assembly effort is kept low.  

The manifold parts are preferably designed in such a way that the outer manifold part overlaps the middle manifold part, so that in a first assembly step, the middle elbow screwed to the cylinder head and then in one second assembly step screwed the outer manifold part becomes. The input flanges on the middle cylinders of a Zy linderbank are freely accessible during assembly and can be used without the use of special tools.

Other advantages and expedient embodiments are the Fi gurenbeschreibung and the drawings. Show it:

Fig. 1 len an exhaust manifold in the installed position with two Krümmertei,

Fig. 2 shows the exhaust manifold in the mounting position.

The exhaust manifold 1 shown in FIGS . 1 and 2 for an internal combustion engine is used for a cylinder bank with four cylinders in series. The exhaust manifold 1 consists of two manifold parts 2 and 3 , which are designed as separate components and are each connected to two cylinders of the cylinder bank. The first manifold part 2 comprises two input flanges 4 , 5 , via which the manifold part 2 can be fastened to the cylinder head of the internal combustion engine, and two exhaust pipes 8 , 9 , which are connected to the input flanges 4 , 5 , and an output flange 12 , which the two Exhaust pipes 8 , 9 are supplied. The second manifold part 3 is constructed analogously to the first manifold part 2 and comprises two input flanges 6 , 7 , two exhaust pipes 10 , 11 and an output flange 13 . Each input flange 4 , 5 , 6 , 7 has recesses 14 which are used to hold screws for attachment to the cylinder head. The further exhaust system connects to the output flanges 12 , 13 .

The exhaust pipes 8 , 9 of the first manifold part 2 with the input flanges 4 , 5 are fastened to the two outer cylinders be. The exhaust pipes 10 , 11 of the second manifold part 3 with the input flanges 6 , 7 are held on the two central cylinders. The second manifold part 3 is at a smaller distance from the cylinder head than the first manifold part 2 , which surrounds the second manifold part 3 . The exhaust pipe 9 of the first manifold part 2 is of elongated design and is guided to the middle cylinders via the two exhaust pipes 10 , 11 of the second manifold part 3 . The extended version of the exhaust pipe 9 has the advantage that the outlet flanges 12 , 13 of the two manifold parts can be arranged approximately side by side, which results in a smaller space requirement.

During assembly ( Fig. 2), the second manifold part 3 is first attached to the cylinder block. The input flanges 6 , 7 are freely accessible through the first manifold part and can be screwed onto the cylinder head with little effort. In a next step, the first manifold part 2 is fastened to the cylinder head with the exhaust pipes 8 , 9 encompassing the second manifold part 3 .

Due to the modular design of the exhaust manifold, the available available space can be optimally used by the individual bend parts optimally to the respective constructive areas be adjusted.

It may be appropriate to ent more than two exhaust pipes speaking input flanges to a separate manifold part summarize. Especially for cylinder banks with more than four cylinders in line can have multiple medium cylinders that directly adjacent to each other or only partially boundaries and intermediate cylinders of a second manifold partially have, acted upon via a common manifold part  become. Other combinations are also possible. For example, both outer cylinders and one or more middle cylinder or an outer cylinder and one or several middle cylinders can be assigned to one manifold part. The exhaust pipes of two manifold parts can run crosswise become. There can also be more than two separately formed crumbs parts are used.

By dividing the exhaust manifold 1 into two or more separately designed manifold parts, there is a two or more flow exhaust manifold. The multi-flow training has the advantage that good torque values and high engine performance can be achieved.

The input flanges assigned to a manifold part can be se be ready or form-fitting with webs be connected.

The exhaust manifold is provided with air gap insulation by the gas-carrying exhaust pipes each from two half-shells are encased and the Ab enclosed in the half-shells gas pipes over spacer elements, in particular heat insulating are formed, enclose at a distance from the inside the half shells are held. Because of the divided construction with several elbow parts, the shell mass is less and thereby reducing the total weight of the exhaust manifold. A white A further advantage in weight is the short overall length of the exhaust gas tubes achieved, which also has the consequence that the in the after following system arranged catalyst faster on operation temperature is heated.  

Reference list

1

Exhaust manifold

2nd

Manifold

3rd

Manifold

4th

Inlet flange

5

Inlet flange

6

Inlet flange

7

Inlet flange

8th

Exhaust pipe

9

Exhaust pipe

10th

Exhaust pipe

11

Exhaust pipe

12th

Output flange

13

Output flange

14

Recess

Claims (4)

1. Gas manifold for an internal combustion engine having a cylinder bank with a plurality of cylinders arranged in series, where an input flange ( 4 , 5 , 6 , 7 ) for an exhaust pipe ( 8 , 9 , 10 , 11 ) can be attached to each cylinder of the cylinder bank is and at least two exhaust pipes ( 8 , 9 ; 10 , 11 ) open into a common output flange ( 12 , 13 ), characterized in that the cylinder bank has at least four cylinders in series and that the exhaust manifold ( 1 ) form at least two separately te elbow parts ( 2 , 3 ), with two input flanges ( 4 , 5 ; 6 , 7 ) with associated exhaust pipes ( 8 , 9 ; 10 , 11 ) and an associated outlet flange ( 12 , 13 ) a coherent elbow part ( 2 , 3 ) form. 2. Exhaust manifold according to claim 1, characterized in that the two outer cylinders of a cylinder bank a Krüm merteil ( 2 ) and the middle cylinders of a cylinder bank min least another manifold part ( 3 ) is assigned. 3. Exhaust manifold according to claim 2, characterized in that the manifold part ( 2 ) assigned to the outer cylinder engages over the manifold part ( 3 ) assigned to the central cylinder. 4. Exhaust manifold according to one of claims 1 to 3, characterized in that more than two input flanges ( 4 , 5 ; 6 , 7 ) with the same number of assigned exhaust pipes ( 8 , 9 ; 10 , 11 ) and an associated output flange ( 12 , 13 ) form a coherent elbow part ( 2 , 3 ).