EP1416148B1 - Noise reduction part for an air intake tube - Google Patents

Description

The invention relates to a sound-reducing component for an air duct for the internal combustion engine according to the preamble of patent claim 1.

It is known to integrate damping elements in air guide tubes of a turbocharger of an internal combustion engine, in particular in the intake tract, in order to damp flow noises. Here, the temperatures and pressure peaks prevailing near the turbocharger place high demands on the materials used.

In the previous solutions silencers are set in different versions and materials as an intermediate piece in the conduit between two pipe sections.

From the DE 195 04 223 A1 For example, a muffler for the intake passage of an internal combustion engine is known, which is arranged between two Luftansaugrohrabschnitten. It consists essentially of the intake manifold made of an elastomer, which has at its two ends connecting sleeves for connection to the Luftansaugrohrabschnitte. The air-conveying intake pipe is surrounded by a damping component in the damping region to form an annular space and has openings in the region of the annular space.

Moreover, from the DE 199 56 165 A1 discloses a device for airborne sound reduction of flow noise of eg turbochargers on internal combustion engines, which is composed of an outer tube and inner tube. The outer shell is shaped so that either only one chamber or a series of chambers with partitions and two connections are formed. It is described that the required fastening systems can be attached directly to these connections. Inside the outer shell is the slotted inner tube.

These solutions have the disadvantage that the two connection points between the damping element and the air duct increase the assembly costs. In addition, they are potential leakages. In addition, due to the high temperatures near the turbocharger, it is problematic to use materials such as plastic.

From the DE 10 52 173 B a sound-reducing component for an air duct is known, which has a damping element as an acoustic filter. The acoustic filter has an inlet extending within a tube end to form an absorption clip. The acoustic filter can be firmly connected to the tube. A disadvantage of the known sound-reducing component, however, is that no measures are taken to ensure a quick and tight connection of the tube or the damping element to a subsequent component.

The object of the present invention is therefore to provide a component for reducing noise emissions for an air guide tube, so that the air guide tube can be connected quickly and tightly to the internal combustion engine, in particular the turbocharger.

The solution to this problem consists in the component with the features of claim 1.

According to the invention the air guide tube is coupled with a special connector to the internal combustion engine, which is designed as a connection / damping unit. This separate connection / damping unit is not as an intermediate piece between two pipe parts of the air duct, but as a connecting piece directly connected to the internal combustion engine, in particular a turbocharger. The connection / damping unit is made in one piece and has a quick coupling as a connection element and an inlet as a damping element. The inlet is inserted from the outside into the connection-side pipe end to form an annular space until the quick-action coupling abuts and is fastened to the abutting surface of the pipe end. The absorption chamber is formed between the particular correspondingly contoured inlet and the tube inner wall of the air guide tube and thus close to the connection. The connection / damping unit and / or the air guide tube are in particular made of the same metallic material as steel, in particular stainless steel, or aluminum, and can withstand even the high temperatures and pressure peaks in the immediate vicinity of the turbocharger.

Due to the one-piece design of the connection / damping unit, the number of components to be connected and thus the necessary connection points or welds significantly reduced, which increases productivity and reduces the risk of leakage. This results in higher strengths of the entire air duct tube and the connection / damping unit.

The combination of quick coupling and noise element creates a space-optimized solution that is particularly suitable for confined spaces.

By the invention it is achieved that a pre-assembled with the connection / damping unit air duct tube can be quickly and tightly connected to the turbocharger due to the quick coupling.

Due to the proposed inlet, which is inserted into the connection-side pipe end of the air guide tube, and its design variety, flow-related noises can be effectively and variably dampened immediately in the vicinity of the turbocharger.

Due to the fact that the damping element is integrated in the connecting piece, the further guide tube can be made flexible beyond the damping region, which relates in particular to its three-dimensional design for the space available individually in the engine compartment. Small and complicated construction spaces can be optimally utilized. By no longer integrating the damping element centrally in the air guide tube, but in its connection-side end, the material wall thickness of the tube can be adapted to different strength requirements quickly and without complicated design changes.

A preferred embodiment of the inlet of the connection / damping unit provides that on the one hand it has a first - preferably hollow-cylindrical - section with perforations or openings whose cross section is smaller than the cross section of the pipe end. On the other hand, it has adjacent thereto second sections. These second sections are widened in an annular manner such that they come into fluid-tight contact with the inner wall of the air guide tube and thus act as a flow barrier. A portion of the air flow is directed through the openings of the first section into the absorption chamber, which is formed in the annular space between the first inlet section and the outer tube wall.

According to the invention, the connection / damping unit is manufactured in one piece and comprises the quick coupling and the inlet. According to a variant of the invention, the integrally produced combination element comprises an inlet, with which a plurality of absorption chambers can be formed. For this purpose, first and second sections of the inlets are formed integrally in each case in alternation. According to another variant, the integrally manufactured combined element of quick coupling and inlet, starting from a base unit, can be extended in modules, with one or more inlet projections, each comprising at least one first and second inlet section, as required. By accepting a further compound, a high variability in the number and shape of absorption chambers is achieved in this way.

The characteristics of the damping may be determined by the length and / or shape of the first inlet portions, i. the portions containing the openings, as well as the second portions and thus the resulting absorption chamber shapes and volumes are adjusted.

The quick coupling itself is a flared tube adapted to the geometry of the neck of the turbocharger. In addition to the fixing function, the quick coupling also performs a sealing function by means of an integrated sealing ring.

The proposed component for the reduction of acoustic emission in the form of a connection piece can in principle be combined with any air duct with a matched diameter. The air guide tube may have over its length an arbitrarily curved three-dimensional contour and / or an arbitrary cross-section, which increases its variability with respect to the installation space.

On the absorption chamber volume and the shape can also influence the contour of the air duct tube, the inlet side surrounds the inlet as an outer tube. The air guide tube is preferably hollow cylindrical over the damping region. It can also be contoured and form the absorption chambers together with the inlet.

Fig. 1

schematisch einen Längsschnitt durch ein Luftführungsrohr mit Anschluss/Dämpfungseinheit,

Fig. 2

eine Seitenansicht auf die Anschluss-/Dämpfungseinheit mit teilgeschnittenem Luftführungsrohr;

Fig. 3

eine weitere Ansicht der Fig. 2;

Fig. 4

die Anschluss-/Dämpfungseinheit im Detail;

Fig. 5

in Gegenüberstellung eine Seitenansicht auf das anschlussseitige Teil eines Luftführungsrohrs mit Schnellkupplung sowie eine Teilschnittansicht;

Fig. 6

den Querschnitt C-C aus Fig. 4.

The invention will be explained in more detail with reference to exemplary embodiments illustrated in the drawings, in which:

Fig. 1

schematically a longitudinal section through an air duct with connection / damping unit,

Fig. 2

a side view of the connection / damping unit with partially cut air duct tube;

Fig. 3

another view of the Fig. 2 ;

Fig. 4

the connection / damping unit in detail;

Fig. 5

in comparison, a side view of the connection-side part of an air guide tube with quick coupling and a partial sectional view;

Fig. 6

the cross section CC Fig. 4 ,

Fig. 1 shows schematically in the overall view of an air duct 1 with integrated Schallresonator or damping element 2. The damping element 2 is part of a attached to the end 3 of the pipe connection / damping unit 4, which simultaneously has a quick coupling 5 for direct connection to a turbocharger (not shown) , The connection / damping unit 4 or the connecting piece thus assumes the connection and damping function. The air guide tube 1 itself can be either the supply channel for fresh air or the air charging tube and / or the discharge channel for exhaust gases.

The noise damper or the damping element 2 is inserted through an inlet 6 inserted into the connection-side pipe end 3 together with the pipe inner wall 7 surrounding it (see also FIG FIGS. 2 and 3 ) educated. Between the correspondingly contoured shaped inlet 6 with perforated sections 8 and the tube inner wall 7, absorption chambers 9, 10 are formed which are fluid-conductively connected to the air flow (compare arrow P). The dashed arrow makes it clear that the air duct can also serve as a discharge channel for gases. Since the damping element 2 or the inlet 6 is connected on the connection side in the form of a connecting piece with the air duct 1, the air duct 1 beyond the damping region 11 can take on any possible design. The Fig. 1 shows a possible installation of the air duct 1 with a corresponding bracket 12. The air duct 1 is bent in the embodiment shown, for example, along its length serpentine, to be passed to other components in the engine compartment of a motor vehicle over. The tube 1, since it is not limited by the connection / damping unit according to the invention, can be bent in any other arbitrary three-dimensional contour and have any desired cross-section over its length.

The FIGS. 2 and 3 Details of the connection / damping unit 4 can be seen. In the embodiment shown here, the quick coupling 5 and the inlet 6, which forms two absorption chambers 9, 10, are made in one piece.

The inlet 6 itself is composed of first and second inlet sections 8, 13. These are arranged alternately next to each other. The first sections 8 are pipe sections, along the circumference in rows perforations 14 and holes (see also Fig. 6 ) are introduced for the gas exchange with the absorption chambers 9, 10. The perforations 14 may take a variety of forms, such as circular or oval openings or slots. Depending on the configuration of the perforations 14 and the cross-sectional configuration of the absorption chambers 9, 10, certain frequency ranges of the vibrations generated by the gas flow can be damped. In the illustrated embodiment, to which the invention is not limited, the perforated portion 8 of the first absorption chamber 9 is formed longer than that of the second absorption chamber 10.

The pipe sections 8 are hollow cylindrical in the example shown and have a cross-section which is smaller than the cross-section of the connection-side pipe end 3. The perforated pipe sections 8 are each surrounded by second pipe sections 13, so that the absorption chambers 9, 10 are limited. These second sections 13 are expanded so far in the form of a ring that they come to rest against the inner wall 7 of the air guide tube 1 in a fluid-tight manner or terminate therewith.

As well as in the 4 and 5 shown, the quick coupling 5 has a widened opening portion 15 for frictional engagement with the neck (not shown) on the turbocharger. On the inlet side follows an over its cross section uniformly shaped portion 16 in the sense of a groove which receives an O-ring seal. The inlet-side part 17 of the quick-action coupling 5 merges into an annular section 18, which at the same time serves as the absorption chamber boundary as well as the connecting surface for the pipe end 3, which is welded to the quick-action coupling 5. The connection point to the quick coupling 5 of the pipe end is good from the Fig. 5 seen.

Hereinafter, a possible way of manufacturing the connection / damping unit will be described. Starting from a tube which has approximately a diameter which corresponds to a later average diameter of the connection / damping unit, the side of the later quick coupling 5 is widened by means of a mandrel and the side of the later insert 6 by rolling and compressing the corresponding sections reduced or enlarged in cross section. Subsequent hydroforming allows calibration to be performed. The perforations 14 in the sections 8 of the first type of the inlet 6 are introduced either by laser welding or by reduced costs by punching. In this case, adjacent holes can be introduced in a single operation over several cylinders.

In this way, an inlet 6, for example, with two absorption chambers 9, 10 are made in one piece with the quick coupling 5. It is also possible to produce the quick coupling in one piece with an inlet with only one absorption chamber and to apply further inlet extensions as needed to the base inlet. In the present case, clarified with Fig. 4 Then, an inlet extension 19 would be firmly attached to the base unit 20 of quick coupling and first absorption chamber, preferably by a weld. Such an inlet extension 19 is composed of a perforated first inlet section 8 and two expanded inlet sections 13. For this purpose, a frusto-conical half shell 21 of the extension 19 is welded to the corresponding half shell 22 of the base unit 20 to form a widened inlet section 13.

The described connection / damping unit as well as the air guide tube can be made of all temperature-resistant metals. Optimum sound absorption is achieved directly in the vicinity of the turbocharger in a small installation space and a small number of connecting seams.

LIST OF REFERENCE NUMBERS

1

Air guide tube

2

damping element

3

connection end of the air duct

4

Connecting / damping unit or connecting piece

5

quick coupling

6

Inlet

7

inner tube wall

8th

first perforated inlet sections

9

absorption chamber

10

absorption chamber

11

attenuation range

12

Holder for the pipe

13

second expanded inlet sections

14

Perforations or holes

15

Opening area of the quick coupling

16

Receiving area for sealing ring

17

On the inlet side of the quick coupling

18

annular area of the quick coupling

19

Inletfortsatz

20

base unit

21

frustoconical half shell

22

frustoconical half shell

P

Arrow airflow

Claims (8)

1. Noise reduction part for an air intake tube (1) of a combustion engine, especially a turbocharger of a motor vehicle, which is adapted for connection to the engine as an inlet duct for fresh air and/or as an outlet duct for exhaust gases wherein the noise reduction part comprises at least one absorption chamber (9, 10) which is in conductive communication with an air stream (P), wherein a silencer element (2) with an inlet member (6) is inserted into a connection-side tube end (3), wherein said absorption chamber (9, 10) is arranged between said inlet member (6) and a tube inner wall (7), wherein an integral metallic connector/silencer unit (4) is attachable to the tube (1), and wherein said inlet member (6) is integral with a rapid action coupler (5) to form said integral metallic connector/silencer unit (4), characterized by the fact that the rapid action coupler (5) is a tube with integrated seal ring whose diameter is larger than that of a first section (8) of the inlet member (6) and larger than that of the connection-side tube end (3).
2. Noise reduction part according to Claim 1, characterized by the fact that the inlet member (6) comprises a first section (8) with perforations (14) and an adjacent second section (13) which is annularly flared and in fluid-tight contact with the inner wall (7) of the air intake tube (1), and that the absorption chamber (9, 10) is arranged between the second section (13) and the rapid action coupler (5) or another second section (13).
3. Noise reduction part according to Claim 1 or 2, characterized by the fact that the inlet member (6) of the integral connector/silencer unit comprises at least one extension (19) which is connectable to the inlet member and which comprises first and second inlet sections (8, 13).
4. Noise reduction part according to Claim 2 or 2, characterized by the fact that said first sections (8) and said flared second sections (13) of the inlet member (6) and/or said inlet member extension (19) are of different lengths and/or shapes for setting desired absorption chamber volumes and/or absorption chamber configurations.
5. Air intake tube (1) for a combustion engine of a motor vehicle which is adapted for connection to said engine, especially a turbocharger, as an inlet duct for fresh air and/or as an outlet duct for exhaust gases and which is fitted with a noise reduction part according to any of the preceding Claims 1 - 4.
6. Air intake tube (1) according to Claim 5, characterized by the fact that the tube has an optionally bent three-dimensional contour and/or an optional cross-section over the full length thereof.
7. Air intake tube (1) according to Claim 5 or 6, characterized by the fact that the tube is in the form of a hollow cylinder or contoured in compliance with the absorption chambers as from case to case provided.
8. Air intake tube according to any of the preceding Claims 5 to 7, characterized by the fact that the abutting surface of the connection-side end (3) of the air intake tube (1) is connected to the rapid action coupler (5) by welding.

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