CH715788A2 - Intake silencer for turbocharger. - Google Patents

Abstract

The invention relates to an intake silencer (1) with a cylindrical housing, with a first and second opposite end wall (20) and an air-permeable jacket wall which extends between the end walls (20) and which forms a main flow inlet for the radial entry of charge air and with an im Area of an end wall formed main flow outlet (H) for the axial air outlet of the charge air, with a plurality of damping elements (50) and connecting webs (60) extending from the second end wall (20) to the first end wall in the interior of the housing, the respective connecting webs (60 ) are arranged between a radially outer side edge region (51) of the damping elements (50) and the jacket wall.

Description

The invention relates to an intake silencer for a compressor of an exhaust gas turbocharger and a turbocharger with such an intake silencer.

A generic filter silencer is known, for example, from EP 0574605 A1. Filter silencers of this type are used, for example, on the intake side of a compressor that compresses combustion air and supplies it to an internal combustion engine. Such a compressor is driven by the exhaust gas turbine of an exhaust gas turbocharger.

This creates sound waves of undesirably high amplitude, which are released to the environment through the air intake duct. These sound waves are therefore usually attenuated by means of a silencer. For this purpose, ambient air flows through a filter arranged on the circumference of a silencer into the interior of the silencer, which is equipped with damping elements, then flows past the damping elements and is deflected by guide elements to the compressor wheel, from which sound waves emanate against the air flow.

From DE 19514990 B4 a filter silencer is known in which the advantages described are to be seen in the fact that only damping elements are used that are of the same type and consist of two parts, namely a damping plate and an absorption element.

[0005] EP 2 386 761 A2 discloses an intake silencer with a cylindrical housing. The housing has opposite, circular end walls and a tubular jacket wall extending between these end walls, which provides a main flow inlet for a main flow of a first medium, with a main flow outlet for the main flow of this first medium being formed in the area of an end wall. When the charge air flows through the intake muffler, there is a deflection from an essentially radial inflow into an essentially axial outflow in order to flow toward the downstream compressor in the axial direction.

[0006] Intake silencers known from the prior art have a number of disadvantages.

The stiffness of the housing is usually not satisfactorily solved or the design has disadvantages for the characteristic natural frequencies and the vibration behavior of the engine. Component natural frequencies are so often in the range of typical main engine excitation orders, which means that the intake silencer is exposed to high dynamic loads. Furthermore, it is increasingly the case that valid guide values for mechanical vibrations of engine components are exceeded in the large engine environment.

[0008] Furthermore, when improving the housing rigidity, it is desirable not to adversely affect the main functions, namely adequate acoustic damping and the lowest possible loss of suction pressure, and to achieve a weight reduction.

In addition, in the intake silencers known in the prior art, the accessibility to individual parts, in particular to the damping elements, is so insufficiently solved that disassembly, such as e.g. necessary for service purposes, is not completely possible when installed on the engine.

Proceeding from this, the present invention is based on the object of creating a novel intake silencer and a turbocharger with such an intake silencer which overcomes the aforementioned disadvantages and can be manufactured inexpensively.

[0011] This object is achieved by the combination of features according to patent claim 1.

A basic idea of the present invention is that the inventive concept provides an easy-to-assemble arrangement of the damping elements of the muffler, which axially into the provided radially inwardly outwardly extending openings or depressions in the end walls, ie in the direction of the rotor axis of the turbocharger. For this purpose, the housing has a plurality of correspondingly shaped openings on one end wall, the cross-sectional shape of which is preferably designed to correspond to the cross-sectional shape of the damping elements and a flow channel runs between each two immediately adjacent damping elements. Dismantling / assembly of the damping elements can be done very easily by removing the covers, which are ideally designed in several parts, without dismantling the perforated sheet metal located on the jacket wall and the typically attached filter mat.

According to the invention an intake muffler with a cylindrical housing is proposed for this purpose, with a first and second opposite end wall (front and rear end wall) and an air-permeable jacket wall extending between the end walls, which forms a main flow inlet for the radial entry of charge air and with a Main flow outlet formed in the area of an end wall for the axial air outlet of the charge air, a multiplicity of damping elements and connecting webs extending from the first end wall to the second end wall inside the housing, the respective connecting webs being arranged between a radially outer side edge region of the damping elements and the jacket wall and thus extend in the axial direction.

The respective connecting webs adjoin the damping elements and for this purpose are preferably in an imaginary extension of the respective damping element. The connecting web width corresponds approximately to the thickness of the damping elements on their radially outer side edge region at the position where the connecting web adjoins the adjacent damping element. As a result, the flow channel is not adversely affected and the free inlet cross section of the filter silencer between two damping elements is not reduced. As a result, the number of connecting ribs attached between the damping elements and in particular their flow-influencing thickness can be reduced with the same or improved housing rigidity, which has an overall advantageous effect with regard to flow losses in the silencer.

In a preferred embodiment of the invention it is provided that the number of connecting webs corresponds to the number of damping elements. It is further advantageous if the damping elements are designed as damping elements that are bent relative to the radial direction, in particular as damping elements bent in a sickle shape. This means that the damping elements, viewed from the radial outside to the radial inside, run in an arc shape.

It is also advantageous if the damping elements protrude with their first edge portion extending in the radial direction into openings formed in the first end wall of the housing and preferably the damping elements project with their second edge portion opposite the first edge portion in recesses or arcuate grooves the second end wall are mounted. A curved shape of the grooves which corresponds to the cross-sectional shape of the damping element in the affected edge section is particularly advantageous.

In a further advantageous embodiment it is provided that in the end wall (ie the front face or front side) in a front wall-side receptacle (z. B. a correspondingly shaped recess) one or more detachable covers or retaining lids are introduced, which in cover the openings in the end wall in their assembled state and preferably hold them in their position.

One end wall of the silencer is closed by means of one or more of said covers after the damping elements have been axially inserted. The damping elements are pressed by the covers in the axial direction into the depressions or grooves on the opposite rear end wall.

The damping elements are formed from an absorber part and preferably two axially extending guide rails and two lateral perforated sheet metal covers. In terms of its density, the absorber part is designed in such a way that, in addition to good acoustic adaptation to the frequency range to be damped, it presses the cover plates against the inside of the openings in the front end wall and against the guide rails, thus ensuring secure attachment.

In an advantageous embodiment it is provided that the respective radially inner guide rails extend from the second end wall to the first end wall (in the axial direction) and the damping elements each with their radially inner side edge region on the inner guide rails and with their radially outer Side edge area are mounted on the outer guide rails. The two axially extending side edge regions of the damping elements are advantageously designed as rounded regions or regions provided with a radius.

It is acoustically advantageous to provide a perforation (ideally a comparable or identical perforation or porosity as the lateral cover plates of the damping elements used, which extends over at least 65% of the total length. The unperforated side remaining unperforated) for each radially inner guide rail In this way, on the one hand, the absorber part is protected in particular in the event of pumping surges of the compressor and, on the other hand, the acoustic damping is hardly impaired.

It can alternatively be provided that the connecting webs each run parallel next to a directly adjacent outer guide rail that this guide rail rests against the respective connecting web. It is also advantageous if the connecting web is a substantially curved or concave shaped Has contour for the engagement of the rounded side edge region of the damping elements.

In a further preferred embodiment of the invention it is provided that a circumferential ring web establishes a connection between the connecting webs themselves and to the housing ribs attached between the damping elements. The ring web serves as a level support for the peripheral perforated plates to form the shell wall, which, in addition to a conventional screw connection, are fixed to the housing via tension belts. The circumferential ring web forms a defined support surface for a tension belt, which is preferably arranged in the center.

Between the housing and the end walls, an insert made of, for example, fibrous felts or fleeces is used for acoustic decoupling and to increase the acoustic insulation. Alternatively, a heavy layer insulation mat (e.g. made of butyl) can be attached to the rear. The structure described is particularly advantageous in that the damping elements can be dismantled and assembled in a simple and inexpensive manner even when they are installed on the engine and turbocharger.

Other advantageous developments of the invention are characterized in the subclaims or are shown in more detail below together with the description of the preferred embodiment of the invention with reference to the figures.

[0026] They show: <tb> Fig. 1 <SEP> shows an exemplary embodiment of an intake silencer in a perspective view; <tb> Fig. 2 <SEP> a perspective view of part of the intake silencer according to the embodiment from FIG. 1, <tb> Fig. 3 <SEP> a perspective view similar to Figure 2, but without the mounted damping elements, <tb> Fig. 4 <SEP> a perspective detailed view of the inside of the rear end wall with partially mounted damping elements, <tb> Fig. 5 <SEP> is a perspective view of the intake silencer according to FIG. 1 with the housing components partially removed <tb> Fig. 6 <SEP> a perspective view similar to FIG. 2 but with a view of the inside of the front end wall.

In the following, the invention will be explained in more detail with reference to FIGS. 1 to 6 using an exemplary embodiment, the same reference symbols in the figures indicating the same functional and / or structural features.

In Fig. 1, an embodiment of an intake silencer 1 is shown in a perspective view.

The intake muffler 1 is shown with a cylindrical housing 10 with a first and second opposite end wall 20, 30 and an air-permeable jacket wall 40 extending between the end walls 20, 30. Foot parts 90 are also located on the front and rear end walls 20, 30.

The jacket wall is open in terms of flow and forms a main flow inlet E for the radial inlet of charge air. In the area of the rear d. H. rear end wall 20 formed main flow outlet H for the axial air outlet of the charge air in the axial direction.

On the front end wall 30 three detachable covers 37 are mounted. In FIG. 5, one of the covers 37 has been removed.

FIG. 2 shows a perspective view of part of the intake silencer 1 according to the embodiment from FIG. 1, the front end wall 30 and the jacket wall 40 being removed.

In the interior of the housing 10, a plurality of damping elements 50 is provided. In addition, connecting webs 60 are formed which extend from the rear end wall 20 in the direction of the unmounted front end wall 30. FIG. 3 shows a partially sectioned view in which the damping elements 50 have been removed from their assembly positions. As can also be seen, the connecting webs 60 are arranged between a radially outer side edge region 51 of the damping elements 50 and the jacket wall 40.

The damping elements 50 are curved sickle-shaped with respect to the radial direction R and protrude with their first edge section 53 running in the radial direction R into recesses 21 in the rear end wall 20.

Furthermore, the damping elements 50 are mounted with their second edge section 54 opposite the first edge section 53 in openings 31 of the front end wall 30. To assemble the damping elements 50, these are passed through the openings 31 in the front end wall 30 until they protrude into the pocket-like depressions 21 and are stored there. In order to secure the damping elements 50 in their installed position, they are held by the covers 37, as shown in FIG.

Furthermore, the damping elements 50 are held from radially inward, essentially U-shaped curved guide rails 33 into which the end edge section of the damping elements protrudes so that they are each supported with their radially inner side edge region 52 on the inner guide rails 33 are.

Furthermore, the damping elements 50 are held by the substantially U-shaped curved guide rails 34, which are arranged radially further outwards and into which the outer end-side edge section of the damping elements protrudes, so that they each with their radially outer side edge region 51 on the outer guide rails 34 are stored.

In Figure 4 it can also be seen that the radially outer guide rails 34 run directly on the connecting webs 60, each parallel to the radially outer side edge of the immediately adjacent damping element 50 and the damping elements 50 rest on the respective connecting web 60 with the guide rails 34 . In the view of FIGS. 2 and 3, three connecting ribs 70 are shown, which run in a stabilizing manner between the rear and front end walls 20, 30 and are each arranged between two damping elements 50. These connecting ribs 70 have approximately the same curvature as the damping elements 50. In addition, an annular web 80 is attached to the outside circumferentially around the connecting webs 60, which connects the connecting webs 60 to one another in a stabilizing manner.

FIG. 6 shows a perspective view with a view of the inside of the front end wall 30.

The implementation of the invention is not limited to the preferred exemplary embodiments given above. Rather, a number of variants are conceivable which make use of the solution shown even in the case of fundamentally different designs.

Claims (14)

1. Intake muffler (1) with a cylindrical housing (10), with a first and second opposite end wall (20, 30) and an air-permeable jacket wall (40) which extends between the end walls (20, 30) and which has a main flow inlet (E. ) for the radial entry of charge air and with a main flow outlet (H) formed in the area of an end wall (30) for the axial air exit of the charge air, a plurality of damping elements (50) and connecting webs (60) of the second end wall (20) to the first end wall (30), the respective connecting webs (60) being arranged between a radially outer side edge region (51) of the damping elements (50) and the jacket wall (40). 2. intake muffler (1) according to claim 1, characterized in that the number of connecting webs (60) corresponds to the number of damping elements (50). 3. Intake silencer (1) according to claim 1 or 2, characterized in that the damping elements (50) are designed as damping elements that are curved relative to the radial direction (R), in particular crescent-shaped curved damping elements. 4. Intake silencer (1) according to one of the preceding claims, characterized in that the damping elements (50) are mounted with their first edge section (53) extending in the radial direction (R) in recesses (21) of the second end wall (20). 5. intake silencer (1) according to claim 4, characterized in that the damping elements (50) with their second, the first edge portion (53) opposite edge portion (54) in openings (31) which are formed in the first end wall (30) , protrude. 6. intake muffler (1) according to one of the preceding claims, characterized in that radially inner guide rails (33) extend from the first end wall (20) to the second end wall (30) and the damping elements (50) each with its radially inner Side edge area (52) are mounted on the inner guide rails (33). 7. Intake silencer (1) according to one of the preceding claims, characterized in that radially outer guide rails (34) extend from the second end wall (30) to the first end wall (20) and the damping elements (50) each with their radially outer side edge region ( 51) are mounted on the outer guide rails (34). 8. intake muffler (1) according to one of the preceding claims 1 to 6, characterized in that the connecting webs (60) each run parallel to the radially outer side edge of the immediately adjacent damping element (50). 9. Intake silencer (1) according to one of the preceding claims 1 to 4 and claim 7, characterized in that the connecting webs (60) each run parallel so next to a directly adjacent outer guide rail (34). 10. Intake silencer (1) according to one of the preceding claims, characterized in that a plurality of connecting ribs (70) between the first and second end wall (20, 30) run, which are each formed between two damping elements (50) and extend radially inward extend radially outward. 11. Intake silencer (1) according to one of the preceding claims, characterized in that a circumferential annular web (80) connects the connecting webs (60). 12. Intake silencer (1) according to one of the preceding claims 4 to 11, characterized in that one or more detachable covers (37) are introduced into the end wall (30) in a receptacle on the end wall, which covers the openings (21) in their assembled state cover in the front wall (30). 13. Intake silencer (1) according to claim 12, characterized in that an insert made of, for example, fibrous felts or fleeces is introduced between the covers (37) and the end wall (30). 14. Intake silencer (1) according to claim 13, characterized in that instead of the insert, a heavy-layer mat or heavy-layer film is attached to the rear of the covers (37).