WO2000025006A1

WO2000025006A1 - Exhaust gas collector flange for an internal combustion engine

Info

Publication number: WO2000025006A1
Application number: PCT/DE1999/003386
Authority: WO
Inventors: Wolfgang Kleiner; Albrecht Geiger; Helmut Held
Original assignee: Wolfgang Kleiner; Albrecht Geiger; Helmut Held
Priority date: 1998-10-28
Filing date: 1999-10-22
Publication date: 2000-05-04
Also published as: EP1127216A1; AU1769000A

Abstract

Disclosed is an exhaust gas collector flange for an internal combustion engine, comprising at least one base part (24) with at least one recess (4) for an exhaust muff (26) and at least one opening (12, 13) towards a cylinder access on the engine block of the engine, in addition to supply means for secondary air and/or recycled exhaust gas, whereby the supply means are in contact with the opening (12, 13) to the cylinder access. According to the invention, the supply means consist of a gas duct (9) that is arranged directly on the at least one base part (24), whereby said gas duct extends over only one partial area of the base part (24) and is formed from two gastight interconnected shell elements (10, 11).

Description

"Exhaust manifold flange for an internal combustion engine"

State of the art

To reduce the environmental impact of exhaust gases from internal combustion engines, u. a. successfully implemented two measures:

a) The catalytic converter, which is regularly installed in internal combustion engines, only fulfills its pollutant-minimizing function from higher operating temperatures. Therefore, so-called secondary air is fed into the combustion chamber, particularly in the cold start phase. The oxygen contained in the secondary air leads to an increase in the heat of combustion of the fuel, which can be used to heat the catalytic converter faster.

b) After the catalytic converter has reached its operating temperature and thus its full effect, exhaust gas or combustion product is recently returned to the combustion chamber of internal combustion engines in order to further minimize pollutant emissions. As a result, the emission of undesirable exhaust gas constituents, such as. B. Nox and Sox reduced.

The feed of the secondary air and / or the recirculated Exhaust gas takes place via air duct systems which, in some known embodiments, are an external component of forged and cast manifold flanges or by means of exhaust manifold flanges in a multi-layer construction (sandwich construction), in the middle layer of which recesses are contained in the form of channels. In addition to the very costly manufacturing processes, these solutions have disadvantages, such as high material and energy consumption and an unfavorable fuel balance due to the comparatively high weight.

In the published patent application DE 43 13 091 AI an exhaust manifold flange is described, which consists of a sealing plate, which has recesses for exhaust ports and openings to cylinder ports on the engine block of an engine. By means of a hood element, a channel is created, through which the openings to the cylinder accesses are connected and, for example, secondary air can be applied. Although this results in a certain reduction in weight, the large-area connection of the hood element to the circuit board, which is in contact with the engine block, is still complex by means of fission gas leakage. In addition, there is a risk that the sealing plate with hood element warps during the soldering process.

The post-published patent application DE 198 27 276 AI relates to an exhaust manifold flange for one

Internal combustion engine, which comprises a base part with recesses for exhaust ports and openings to cylinder accesses on the engine block of the engine and supply means for secondary air and / or recirculated exhaust gas, the supply means being connected to the openings to the cylinder accesses. The feed means comprise a channel arranged directly on the base part, for the formation of which at least one cover element is provided, which extends only over a partial area of the base part extends. In this way, further weight savings can be achieved. When designing the cover element in the sectional view as a U-profile, however, high demands must be placed on the soldering process in order to obtain a channel volume through the gas-tight soldering of the cover element to the flange base part. This is because the soldered connection essentially only results from the contact surface of the edges of the cover element which is U-shaped in cross section. This relatively small-area soldered connection is exposed to high stress during operation at frequently changing temperatures, which can possibly lead to fatigue of the soldered connection, which ultimately results in a leakage of the gas channel if the soldered connection breaks. Due to the comparatively low inherent rigidity of the base part, there is also the risk that the base part may become warped when soldered to the cover element, which cannot be absorbed by the cover element due to the comparatively small contact area of the cover element. In this case, the component then has poor evenness, making it difficult or impossible to install.

Object and advantages of the invention

The invention has for its object to provide an exhaust manifold flange with means for supplying secondary air and / or recirculated exhaust gas, which can be manufactured comparatively easily and has a high reliability in operation with a low weight.

This object is solved by the features of claim 1. Advantageous and expedient developments of the exhaust manifold flange according to the invention are specified in the subclaims.

The invention relates to an exhaust manifold flange for a _V internal combustion engine comprising at least one base part with at least one recess for an exhaust port and at least one opening to a cylinder access on the engine block of the engine and supply means for secondary air and / or recirculated exhaust gas, the supply means being connected to the at least one opening to the cylinder access stands. The essence of the invention is that the supply means have a gas channel arranged directly on the at least one base part, which extends over only a partial area of the base part and is formed from two shell elements connected to one another in a gastight manner. This procedure makes it possible to produce an exhaust manifold flange with a comparatively low weight, in which the soldered connection can be carried out reliably on the base part due to a sufficiently flat support of the gas channel. The relatively large areas lying against each other prevent a no longer tolerable heat distortion during the soldering process. The resulting solder joint also has excellent long-term load values.

In a particularly advantageous embodiment of the invention, a plurality of individual base parts are provided which are connected by a two-shell gas channel arranged on these base parts in such a way that the gas can be routed to the individual base parts via the gas channel. As a result of this measure, not only is the gas duct used as a central gas routing system, but it also takes on the function of a bulky connecting strip between the individual base parts.

For fastening the exhaust manifold flange and / or for securely connecting the openings in at least one base part to the cylinder accesses on the engine block, it is also proposed that bores arranged one above the other in the shell elements of the gas duct and in the base part are provided, which are penetrated by a screw connection. In this context, it is particularly preferred if a sleeve element is fitted in at least one bore arrangement in such a way that the sleeve absorbs forces of the screw connection which would otherwise have to be absorbed in full by the shell elements of the gas channel. This measure not only leads to a secure power transmission of the screw connection to the sealing area of the exhaust manifold flange, but also has a favorable setting behavior of the individual screws.

In order to be able to carry out a simple pre-adjustment of the individual components required for the exhaust manifold flange, d. H. in the case of a plurality of base parts, an alignment of these base parts with the gas channel formed from shell elements, it is further proposed that the sleeve penetrate the bores of the shell elements lying one above the other and end in the bore located in the base part, the sleeve and bores forming an interference fit and in a few Contact area the sleeve is provided with a knurl. This means that the entire exhaust manifold flange can be pre-adjusted before the soldering process and remains stable during the soldering process.

In a further advantageous embodiment of the invention, the gas channel has a cross-sectional widening at a point at which it is penetrated by a screw connection. This avoids a reduced gas supply to the entrances on the engine block due to constrictions.

Finally, it is advantageous if the gas channel has a connection piece which is molded onto one of the gas channel shells. By this measure, an otherwise usually additional connecting piece, for example in the form of a connecting nipple.

drawings

Several exemplary embodiments of the invention are illustrated in the drawings and explained in more detail with the specification of further advantages and details.

Show it

La a base part of an exhaust manifold flange in plan view,

Fig. Lb and c sectional views of the base part

1 according to the section lines A-A and B-B shown in FIG. 1,

2a to d base parts of an exhaust manifold flange, which is composed of individual base parts, in plan view,

Fig. 3 according to the invention

Exhaust manifold flange with gas duct in a partially cut top view,

3b is a broken sectional view taken along section line A-A in Fig. 3a,

Fig. 3c is a sectional view of the

Exhaust manifold flange from Fig. 3a according to the section line B-B drawn in Fig. 3a,

3d is an enlarged view of the in

3c drawn section Y, Fig. ₄ a is a plan view of an inventive

Gas channel,

Fig. 4b to d sectional views of the gas channel

Fig. 4a according to the section lines A-A to C-C shown in Fig. 4a.

Description of the embodiments:

1a to c, a base part 1 is shown, in which a connecting bar 2 connects base part sections 3, in each of which a recess 4 for an exhaust pipe (not shown) is provided. This base part 1 consists of punched flat material. 2a to d base parts 5 to 8 of preferably also punched-out flat material are shown, which are connected by means of a gas channel according to FIGS. 4a to d to form a complete exhaust manifold flange. Such a structure has a number of advantages. First of all, a connecting bar 2, as shown in FIG. 1 a, can essentially be dispensed with. This saves material, which has a favorable effect on the weight of the exhaust manifold flange. A gas channel 9 according to FIGS. 4a to d, which is composed of two shell elements 10, 11 placed one inside the other, can be soldered to the individual base parts via comparatively large contact surfaces. Through openings 12 in the gas channel 9 are positioned congruently with openings 13 in the individual base parts 5 to 8.

For the pre-adjustment of the gas channel 9 with respect to the individual base parts 5 to 8, a sleeve 14 (see FIG. 3d) is preferably introduced into the openings arranged one above the other, advantageously at least one Has a press fit in the opening 13 of the base parts and is preferably knurled at least in the contact region with the wall of the openings 13 on the outside. This not only ensures secure positioning during the pre-adjustment, but also during the soldering process. During the soldering process, a warping of the small-area individual base parts 5 to 8 can essentially not occur, since there is also a large-area solder connection point on the individual base parts to the gas channel 9. This also applies if the individual base parts 5 to 8 consist of simple flat material. Should there be a certain delay in the gas channel 9, e.g. B. take place when soldering the shell elements 10, 11, this can be regularly compensated for in the assembly of the finished manifold flange in the elastic region of the gas channel, so that sealing problems of this exhaust manifold flange on an engine block can be largely avoided.

Advantageously, a connecting piece 15 is integrally formed on the front shell element 10 of the exhaust duct 9. This saves the additional insertion of such a connection.

When adjusting the individual base parts 5 to 8, it should also be taken into account that openings 16 in the shell element 11 of the gas channel 9 to be soldered to the base parts 5 to 8 are arranged congruently via corresponding openings 17 in the base parts 5 to 8. The openings 16, 17 serve as access to cylinder accesses on the engine block for the supply of secondary air and / or exhaust gas. On the other hand, screw connections for fastening the exhaust manifold flange to the engine block are passed through the openings 12, 13. For the attachment of additional screw connections, further openings 19 are provided at opposite locations with respect to the recesses 4 in the respective base part. Areas in the gas channel 9 by a screw connection, for. B. a screw 19, as shown in FIGS. 3b to d, are penetrated, advantageously have cross-sectional expansions, e.g. B. in the form of bulges 20, 21, 22. Thus, the flow of the gas to the entrances to the engine block is not hindered by any narrowing of the cross-section.

An exhaust manifold flange 23, which has a single base part 24, is shown in FIGS. 3a to d. The gas duct according to the invention is also advantageous in this case. Because, apart from the bulges 20, 21, 22, the gas channel 9 is soldered to the base part 24 with its full surface. This not only creates a very reliable soldered connection, but also warps the base part

24 during the soldering process due to the large surface area kept in a tolerable range. The pre-adjustment of gas channel shell elements 10, 11 can be carried out in the same way as described above, by means of preferably knurled sleeves 14, which are inserted into the openings 12, 13 (see in particular Fig. 3d).

The sleeves 14 also ensure that forces are absorbed by screw connections that would otherwise have to be fully transmitted by the shell elements in the gas channel. This results in a favorable settlement behavior of the screws 19.

An integrally molded one is an example in FIG. 3b

Connection piece 15 shown, with a connecting element

25 for further connection with z. B. was provided a connecting pipe.

In FIG. 3c, an exhaust nozzle 26 inserted into a recess 4 is also shown. These exhaust ports 26 are also indicated in Fig. 3a. Reference symbol list:

1 base part

2 connecting bar

3 base section

4 Recess for an exhaust pipe

5 base part

6 base part

7 base part

8 base part

9 gas channel

10 shell element

11 shell element

12 opening

13 opening

14 sleeve

15 connecting pieces

16 opening

17 opening

18 opening

19 screw

20 bulge

21 bulge

22 bulge

23 Exhaust manifold flange

24 base part

25 connecting element

26 Exhaust nozzle

Claims

Expectations :

1. Exhaust manifold flange for an internal combustion engine, which comprises at least one base part with at least one recess for an exhaust pipe and at least one opening to a cylinder access on the engine block of the engine and supply means for secondary air and / or recirculated exhaust gas, the supply means with the opening to the cylinder access in Connected, characterized in that the supply means have a gas channel (9) which is arranged directly on the at least one base part (5, 6, 7, 8, 24) and extends over only a partial area of the base part, and is gas-tightly connected to one another Shell elements (10, 11) is formed.

2. Exhaust manifold flange according to claim 1, characterized in that a plurality of individual base parts (5, 6, 7, 8) are provided which are connected by a two-shell gas channel (9) arranged on these base parts in such a way that the gas flow to the individual base parts can be done via the gas channel.

3. Exhaust manifold flange according to one of the preceding claims, characterized in that for fastening the exhaust manifold flange and / or for securely connecting the openings in at least one base part to the cylinder accesses on the engine block in the shell elements (10, 11) of the gas channel (9) and in the base part (5, 6, 7, 8, 24) openings (12, 13) which are arranged one above the other and which are penetrated by a screw connection (19).

4. Exhaust manifold flange according to claim 3, characterized in that in at least one opening arrangement, a sleeve element (14) is fitted such that the sleeve (14) absorbs screwing forces, which otherwise in full the shell elements (10, 11) of the gas channel (9) would have to be accommodated.

5. Exhaust manifold flange according to claim 4, characterized in that the sleeve (14) penetrates the superimposed openings of the shell elements, ends in the underlying opening (13) in the base element, the sleeve and opening forming an interference fit and the sleeve in at least one contact area (14) is provided with a knurl.

6. Exhaust manifold flange according to one of claims 3 to 5, characterized in that the gas channel (9) at a point at which the gas channel (9) is penetrated by a screw connection (14) has a cross-sectional widening (20, 21, 22) .

7. exhaust manifold flange according to one of the preceding claims, characterized in that the gas channel (9) has a connecting piece (15) which to one of the

Gas channel shells (10, 11) is formed.