DE19827276A1 - Exhaust manifold flange for internal combustion engine - Google Patents

Abstract

The exhaust gas manifold flange has feeds at the openings (9) to the cylinders for secondary air and/or exhaust feedback. The feeds are a channel directly at the flange base (1) section, formed by at least one cover which extends over a section of the base.

Description

The invention relates to an exhaust manifold flange for a Internal combustion engine according to the preamble of Claim 1.

State of the art

To minimize pollutants in exhaust gas flows from Internal combustion engines are recently preferred so-called secondary air and / or recirculated exhaust gas in the Combustion chamber of the engine fed. This will the combustion reaction of the engine in the way affects that the formation of undesirable Reaction products such as NOx and SOx significantly reduced.

The feed of the secondary air and / or the recirculated Exhaust gas is preferably carried out in known embodiments about air duct systems that are external components of Forged and cast manifold flanges are. The necessary Connection channels from an air intake system to the Exhaust manifold flange and thus to the combustion chamber but with a large manufacturing effort and thus high Manufacturing costs associated.  

This led to exhaust manifold flanges in a multi-layer construction (Sandwich construction of at least three layers) design that in their middle layer recesses in Form of channels are introduced. The layers concerned (Single flanges) are regularly used as stamped flanges are manufactured and are then made using cradles congruently placed on top of each other and soldered. That for Brazing of the individual layers necessary copper solder is in Form of solder paste in designated recesses (Solder deposits) overlying the bottom layer Single flanges introduced. To ensure congruence, So the individual layers must have a stable position Partial flanges before the soldering or heat treatment process additionally welded together in several places become.

The manufacturing process can be summarized as follows:

• 1. Production of the individual punch flanges with solder deposits
• 2. Congruent positioning of the Single layers in special holding devices
• 3. Welding the individual layers on the circumference of the Flange package
• 4. Application of solder paste into the solder deposits
• 5. Brazing the individual layers and the pipe socket underneath Protective gas atmosphere.

Embodiments produced in this way are with a enormous use of materials and energy. this leads to a high environmental or resource pollution. Next to it the high weight to an unfavorable Fuel consumption balance in motor vehicles.  

In addition to the very costly manufacturing process for casting and forged gas manifold flanges are the disadvantages Layer flange designs even more diverse and therefore to look at in more detail.

The following problems can arise in connection with the production of "exhaust manifold flanges with secondary and / or exhaust gas recirculation channels" by means of sandwich construction:

• a) The reliable soldering of the relatively large area Layer flanges require very good flatness individual flange surfaces lying on top of each other. Irregularities in the flange surfaces lead to changed capillary filling forces and thus too different soldering qualities, what in one poor strength of the solder joint result can.
• b) For the complete soldering of these relatively large areas Large quantities of solder are required for the layers Driving total manufacturing costs up.
• c) To maintain the positional stability of the individual layers necessary previous welding is a additional energy and cost-intensive Manufacturing step.
• d) The previously used channel configuration is material and very expensive to manufacture, because the complete middle flange layer only serves to create volume for the secondary air duct. A much of the remaining around the canal Flange layer mass is therefore non-functional Meaning and unnecessarily represents almost 30% of the Total weight of the flange.  
• e) The complete heating necessary for the soldering process (100% heat penetration is required) Flange packages on soldering temperatures up to approx. 1080 ° C due to the relatively large and compact Flange package dimensions only possible with high energy consumption.
• f) The heat distortion caused by the soldering process of concave or of convex surface curvatures of the Flange pack must go through an expensive process Post processing can be compensated.
• g) The welding of the manifold and the soldered flange package can occur due to the local heating of the brazing alloy Welding temperature for diffusion of the solder melt into the Welded connection lead to loss of strength the weld can lead.

Object and advantages of the invention

The invention has for its object a Exhaust manifold flange ready to provide, the more economical, with comparatively less material and energy consumption and so that resources can be produced more gently. In doing so a weight saving can be achieved with the Reduction of fuel consumption in Bring internal combustion engines of motor vehicles leaves.

This object is solved by the features of claim 1.

In the subclaims are advantageous and expedient Developments of the device according to the invention specified. The invention relates to an exhaust manifold flange for a Internal combustion engine, which has a base part Recesses for exhaust ports and openings too  Cylinder accesses in the engine block of the engine as well Supply means for secondary air and / or recirculated Exhaust gas comprises, the feed means with the openings are connected to the cylinder accesses. The core of the The invention now lies in the fact that the supply means one channel located directly on the base part, to the formation of which is provided at least one cover element, that is only over a portion of the base part extends. This simplified structure makes one significant material and weight savings in the state of the Technology known exhaust manifold flanges with integrated Secondary air and exhaust gas recirculation channels achieved.

In a further preferred embodiment of the invention are used to attach the exhaust manifold flange and / or secure connection of the openings in the base part with the Cylinder accesses on the engine block in at least one Cover element and one above the other in the base part Bores provided by a screw connection can be penetrated. This measure has the advantage that the attachment of the cover element on the base part, the Fastening the exhaust manifold flange and manufacturing a tight connection of the secondary or Exhaust gas recirculation duct on the engine block through the same Screw connections are made. This will continue prevented, provided the cover element, as below described, is soldered to the base part that a Raising or bursting of the solder joints, especially at high ones Engine temperatures occurs.

In a particularly preferred further embodiment of the Invention is in at least one hole arrangement for the Attaching a screw connection to a sleeve element like this fitted that the sleeve after a predetermined deformation of the at least one cover element and / or the base part by the forces of the screw connection or connections  further deformation forces on at least the cover element on takes. In a preferred embodiment, this is Sleeve element designed so that it can accommodate Forces that would cause undesired deformation, between a contact surface of the screw connection and the Engine block supports. Through these measures according to the invention the cover element can be used to form the channel produce comparatively thin-walled elastic material, without running the risk that the cover element on the Yields until the detachment of the entire manifold flange especially in the area of Connection openings to the engine block takes place. This would cause the engine to malfunction. The use of a thin-walled cover element saves manufacturing costs and reduces the weight of the exhaust manifold flange, which last End up reducing fuel consumption.

In order to obtain a gastight formation of the channel, it is also advantageous if the elements for channel training be soldered to the base part or similarly connected.

Especially when using inventive Sleeve elements, can be a particularly effective soldering to reach. Because the sleeve elements can before soldering as position aids for the exact arrangement of the cover element be used on the base part by going through the Bores inserted in the cover element and base part and if necessary be jammed. The sleeve can advantageously be over fix a press fit. This is a staple of the Cover elements on the base part z. B. by spot welds dispensable for soldering.

To detach the manifold flange at high temperatures to safely avoid the internal combustion engine, it is im Another advantage if means for Stiffening of the base part are provided.  

In a preferred embodiment, the means for Stiffening a flare that is at least partially extends over the outer contour of the base part. In this Context, it is also preferred if the base part is made from a steel sheet.

It is to achieve a particularly simple construction moreover preferred if the formation of the channel Cover element is bowl-shaped and rests on the base part. In the case of a flanging on the base part, it is for this Embodiment further advantageous if the edged Areas on the cover element to form the shell suitable dimensions of the cover element at the flange of the Base part, as if in a way two shells with the open side exactly fitting into each other. In this case, too, a previous fixing of the Cover elements through the precise insertion before z. B. one Soldering process not necessary. The contiguous Flanges or upstands offer good flow paths for the solder. About the height of the upstand on the cover element or the flanging on the base part can also be the Channel cross-section can be determined.

In a likewise advantageous embodiment of the Invention is the cover element a cover plate, which for Formation of the channel congruent on one on the base part overlay intermediate plate with cutouts for the Channel guides is arranged. This represents one comparatively simple solution where the Channel parts z. B. produced by simple punching can be.

To the existing flanges on the base part for channel formation To be able to use, it is also preferred if the Cover element has an L or U profile shape.  

For the use of standard components for channel formation, it is also advantageous if the cover element Includes square tube that is placed on the base part.

It is also advantageous if the cover element from one Part of the base part is formed by this into a Box profile is bent. That way it can Basic element with secondary and / or exhaust gas recirculation duct be made from a single sheet.

Finally, it is particularly preferred if the exhaust ports are soldered into the base part. This is an advantage of Flange and possibly cracking on the flange avoided occur during an otherwise usual welding process.

drawings

Three embodiments of the invention are in the Drawings shown and in the description below stating further advantages and details explained.

Show it

Fig. 1 a first exhaust manifold according to the invention in plan view,

Fig. 1A-F are sectional views of the embodiment of Fig. 1 according to the depicted in FIG. 1, section lines AA to FF,

Fig. 2 is a side view of the embodiment according to Fig. 1,

Fig. 3 shows a second embodiment of this invention a Abgaskrümmerflansches in plan view,

Fig. 3A is a sectional view of the embodiment of FIG. 3 taken along section line AA in Fig. 3,

Fig. 4 shows a third embodiment of an exhaust manifold flange according to the invention in plan view and

FIGS. 4A-F, various sectional views of the embodiment of Fig. 4 along the indicated in FIG. 4 cut lines AA to FF.

Description of the embodiments

In Figs. 1 and 2, a first embodiment of the invention is shown. The sections AA to FF according to FIGS. 1A-1F are intended to further illustrate the exemplary embodiment. This exemplary embodiment comprises a base part 1 with four receiving openings 2 for each exhaust pipe 14 (see FIG. 1A) corresponding to the number of cylinders of an engine. Furthermore, this exhaust manifold flange has an intermediate plate 3 running along the manifold receiving openings, which has a recess 4 (shown in broken lines in FIG. 1) and, together with a congruent cover plate 5, forms a secondary air and / or exhaust gas recirculation channel arranged directly on the base part 1 . The intermediate plate 3 is with the base part 1 and the cover plate 5 z. B. soldered to obtain the desired gas tightness of the secondary air and / or exhaust gas recirculation channel. Furthermore, the base part 1 is fastened together with the intermediate plate 3 and the cover plate 5 via screw connections 6 (only shown in the sectional view of FIG. 1A) to an engine block (not shown), for example. For this purpose, holes 7 , 8 are provided in the base part 1 and in the cover plate 5 (see FIG. 1A). For further fastening of the exhaust manifold flange to an engine block, 2 further bores 13 are positioned on the base part 1 above each receiving opening. In order to provide access of the secondary air duct to the corresponding cylinder opening on an engine block, the base part 1 has openings 9 which are encompassed by the recess 4 in the cylinder plate 3 . The cover plate 5 has a feed connector 10 for feeding secondary air and / or recirculated exhaust gas into the recess 4 of the channel. The receiving openings 2 and the circumference of the base part 1, with the exception of the long side on which the secondary air and / or exhaust gas recirculation duct runs, have flanges 11 , 12 . The flanges give the base part a very high degree of rigidity, in particular bending stiffness, so that the entire flange can be produced from very thin sheet steel, that is to say with very little material, given a given maximum bending stiffness.

In FIGS. 3 and 3A, a second inventive embodiment is illustrated of a Abgaskrümmerflansches, in which a similar in comparison to the first embodiment base portion 20 is used. The base part also comprises four receiving openings 21 for a corresponding number of exhaust ports.

In contrast to the first exemplary embodiment, however, only one cover element 22 is used to form the secondary air and / or exhaust gas recirculation channel, which is shaped like a shell for this purpose (see section-by-section illustration in FIG. 3 and FIG. 3A). The shell-shaped cover element 22 sits directly on the base part 20 , the channel volume formed thereby being connected to openings 23 which provide access to corresponding cylinder openings on an engine block. To attach this exhaust manifold flange with z. B. screws are provided on the base part 20 and in the cover element 22 holes 24 , 25 or above the receiving openings 21 holes 26 .

A sleeve 27 is inserted into the congruent bores 24 and 25 , as can be seen in FIG. 3A. The sleeve 27 has a collar 28 which rests on the cover element 22 . The sleeve 27 according to the invention has several advantages. First, it serves as a positioning aid for the cover element 22 in front of a z. B. Brazing process. For this purpose, the sleeve 27 is inserted through the bore 24 in the cover element 22 and into the bore 25 of the base part. In the case of a precisely fitting design of the sleeve (this can also be easily pressed in as in a press fit), the cover element 22 is exactly positioned and fixed with respect to the base part 20 , so that it is not necessary to apply, for example, weld tack points before a brazing process. However, the brazing process is carried out so that the sleeve 27 is still movable in the bore 25 of the base part 20 . By this measure, when tightening a screw 29 , the screw head 30 of which rests on the collar 28 of the sleeve 27 , the cover element 22 is deformed only until the end of the sleeve 27 located in the bore 25 of the base part 20 abuts an engine block (not shown).

FIG. 3A shows the relaxed state in which the end of the sleeve 27 located in the bore 25 is at a small distance "x" from the contact surface 31 of the base part 20 , which rests on an engine block in the installed state. Only in this area is deformation of the cover element 22 permitted. This measure thus prevents a z. B. thin sheet metal produced cover element 22 yields until the base part 20 can stand out from an engine block, which can ultimately lead to a leak between supply channels to an engine block and the openings 23 in the base part 20 . Due to the size of the distance x between the end of the sleeve 27 and the contact surface 31 of the base part in a relaxed state, the size of the contact pressure on the cover element 22 and thus the base part 20 can be adjusted so that there is no permanent deformation of the cover element.

In the sectional view of FIG. 3A, an exhaust connector 32 inserted into the receiving openings 21 is shown in sections in the left half. This can e.g. B. soldered instead of a welding process to avoid cracking in the high thermal load during welding in the flange. In order to increase the rigidity of the base part 20 , this has a flange 33 with the exception of the peripheral region on which the cover element 22 runs.

A third exemplary embodiment according to the invention is shown in FIG. 4 and the associated cuts. Shown to FF 4A-Fig. Along section lines AA. The exemplary embodiment comprises a base part 40 which is identical to the first exemplary embodiment, with the only difference that the outer flange 41 on the base part 40 is fully circumferential. Comparable construction elements are therefore provided with the same reference symbols.

In order to form a secondary air and / or exhaust gas recirculation channel, a shell-shaped cover element 42 is inserted into the base part 40 in such a way that the upturned areas of the cover element 42 on the circumferential flange 41 of the base part 40 with the exception of a section in the area of the two outer receiving openings 2 for exhaust ports 43 (only indicated in Fig. 4A). In order to replace the flanging which is missing at the end points in the area of the two outer receiving openings 2 for exhaust pipe 43 for the cover element 42 ending there, web elements 44 are provided (see FIG. 4) which take over this task. In order to obtain a tight duct system, the cover element is soldered to the base part along the edge of the cover element. This shell construction results in a very high rigidity of the exhaust manifold flange, so that advantageously the individual shells (base part 40 and cover element 42 ) made of very thin, e.g. B. sheet steel, ie can be produced with very little material. According to the sectional drawings Fig. A to Fig. F, the base part 40 and the cover member 42 are formed and constructed so that they can be pressed in a stable position in a simple manner, each with the open sides pointing to each other and inserted into each other if necessary. In addition to the channel design shown in the drawing, larger channel cross-sections can also be achieved without problems by varying the height of the flange 41 of the base part 40 and / or the edge of the cover element 42 . To fasten the exhaust manifold flange, bores 13 , 45 , 46 are provided in the base part 40 and possibly in the cover element 42 (see in particular FIG. 4A, in which a screw connection 47 is indicated).

In order to prevent the cover element 42 from being deformed in an undesired manner at the points at which the exhaust manifold flange is screwed together with the base part 40 and the cover element 42 , these points are underlaid or supported by sleeve or support elements 48 .

In the exemplary embodiments according to the invention are omitted at least those listed in the prior art Steps 1-3. Due to the low use of materials  resources are conserved and by saving weight of over 50% compared to conventional embodiments can achieve fuel savings in motor vehicles become. This in turn leads to environmental protection. Both Embodiments according to the invention also do not occur Interaction of solder melt and welded connections or no problematic solder diffusion. Overall, they are Manufacturing costs also by a much lower Use of solder quantity greatly reduced.  

Reference list

1

Base part

2nd

Receiving opening

3rd

Intermediate plate

4th

Recess

5

Cover plate

6

Screw connection

7

drilling

8th

drilling

9

opening

10th

Feed connector

11

Flanging

12th

Flanging

13

drilling

14

Exhaust pipe

20th

Base part

21

Receiving opening

22

Cover element

23

opening

24th

drilling

25th

drilling

26

drilling

27

Sleeve

28

collar

29

Screws

30th

Screw head

31

Loading area

32

Exhaust pipe

33

Flanging

40

Base part

41

Flanging

42

Cover element

43

Exhaust pipe

44

Web elements

45

drilling

46

drilling

47

Screw connection

48

Sleeve element

Claims (13)

1. Exhaust manifold flange for an internal combustion engine, exhaust ports ( 14 , 32 , 43 ) and openings ( 9 , 33 ) to cylinder accesses to 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 stand, characterized in that the feed means comprise a channel arranged directly on the base part, for the formation of which at least one cover element ( 5 , 22 , 42 ) is provided, which extends only over a partial area of the base part ( 1 , 20 , 40 ). 2. Exhaust manifold flange according to claim 1, characterized in that for fastening the exhaust manifold flange and / or for securely connecting the openings in the base part to the cylinder accesses on the engine block in at least one cover element ( 5 , 22 , 42 ) and in the base part ( 1 , 20 , 40 ) bores ( 7 , 8 ; 24 , 25 ; 45 , 46 ) arranged one above the other are provided, which can be penetrated by a screw connection ( 6 , 29 , 47 ). 3. exhaust manifold flange according to claim 2, characterized in that in at least one bore arrangement ( 7 , 8 ; 24 , 25 ; 45 , 46 ) a sleeve element ( 27 , 48 ) is fitted such that the sleeve after a predetermined deformation of the at least one cover element and / or the base part absorbs further deformation forces on at least the cover element due to the forces of the screw connection. 4. Exhaust manifold flange according to one of the preceding claims, characterized in that the elements ( 3 , 5 , 22 , 42 ) for channel formation with the base part ( 1 , 20 , 40 ) are soldered. 5. Exhaust manifold flange according to one of the preceding claims, characterized in that means for stiffening the base part are provided on the base part ( 1 , 20 , 40 ). 6. exhaust manifold flange according to claim 5, characterized in that the means for stiffening comprise a flange ( 11 , 12 , 33 , 41 ) which extends at least partially over the outer contour of the base part. 7. Exhaust manifold flange according to one of the preceding claims, characterized in that the base part ( 1 , 20 , 40 ) consists of a steel sheet. 8. Exhaust manifold flange according to one of claims 1 to 7, characterized in that the at least one cover element ( 22 , 42 ) is shell-shaped and rests on the base part to form the channel. 9. Exhaust manifold flange according to one of claims 1 to 7, characterized in that the at least one cover element is a cover plate ( 5 ) which is congruent to form the channel on an intermediate plate lying on the base part ( 3 ) with recesses ( 4 ) for the channel guide is arranged. 10. exhaust manifold flange according to one of claims 1 to 7, characterized in that the at least one cover element has an L or U profile that for the formation of the channel with an appropriately prepared area of the base part cooperates.   11. Exhaust manifold flange according to one of claims 1 to 7, characterized in that the at least one cover element comprises a square tube, which is placed on the base part becomes. 12. Exhaust manifold flange according to one of claims 1 to 7, characterized in that the cover element from one part of the base part is formed by this Box profile is bent. 13. Exhaust manifold flange according to one of the preceding claims, characterized in that the exhaust pipe ( 14 , 32 , 43 ) in the base part ( 1 , 20 , 40 ) is soldered.