KR20030032013A - Mounting device for a filter and sound damper unit on the compressor input of a turbocharger - Google Patents

Abstract

The present invention relates to a fixing device for detachably fixing a filter sound absorber to a casing portion of a compressor belonging to a turbocharger for an internal combustion engine, wherein the filter sound absorber can be fixed to the compressor inlet with the aid of the fixing member. The fixing device 36 comprises a vibration separator 46 arranged between the casing portion 32 of the compressor 18 and the filter absorber 16, for example when the filter absorber 16 is excited by an engine. Vibrates at a different frequency than the turbocharger casing 28 or the turbocharger casing.

Description

Fixing device for filter sound absorber at compressor inlet of turbocharger {MOUNTING DEVICE FOR A FILTER AND SOUND DAMPER UNIT ON THE COMPRESSOR INPUT OF A TURBOCHARGER}

High noise is emitted from the compressor inlet of the turbocharger. Thus, filter absorbers that reduce the noise emissions are generally arranged at the compressor inlet. Since the filter absorber is firmly fixed to the casing part of the compressor and is not separated from the turbocharger in vibration, the vibration of the turbocharger is transmitted to the filter absorber. In general, the turbocharger is fixed directly to a bracket of an internal combustion engine or through a fastening foot. The axial distance between the stator and the filter absorber is usually very large. When the turbocharger is excited by the vibration of the engine and / or set to natural frequency vibration, the amplitude is greatest in the filter absorber due to the geometry. This is undesirable, especially since high loads are caused on the material. In countries with corresponding provisions, these vibration problems may even be rejected in technical licensing.

The present invention relates to a fixing device for detachably fixing a filter sound absorber to a casing portion of a compressor belonging to a turbocharger for an internal combustion engine, wherein the filter sound absorber can be fixed to the compressor inlet with the aid of the fixing member.

1 is an axial cross-sectional view of a turbocharger with a fixing device according to the prior art and with a filter absorber arranged at the compressor inlet,

FIG. 2 is an axial sectional view similar to FIG. 1, but an enlarged partial sectional view of a first embodiment of a fixing device according to the present invention; FIG.

FIG. 3 is a view similar to FIG. 2, with an enlarged partial sectional view of a second embodiment of a fixing device according to the invention;

4 is a sectional view of the fixing device of FIG. 3 with a securing member, and

FIG. 5 is an enlarged partial cross-sectional view of a third embodiment of a fixing device according to the invention, with a view similar to FIG. 2;

Explanation of reference numerals

10: longitudinal axis of the turbocharger 12: turbocharger

14 compressor inlet 16: filter absorber

18 compressor 20 turbine

22: compressor rotor 24: turbine rotor

26 shaft 27 compressor casing

28: turbocharger casing 29: turbine casing

30: bearing casing 31: holder

32: casing portion 34: bracket

36: fixing device 38: first fixing orifice

40: flange 42: second fixed orifice

44: fixed member 46: vibration separator

47: separating member 48: hollow cylinder

50: member flange 54: spacer bush

56 hollow cylinder 58 bush flange

60 member 62: annular groove

64: fixed ring 66: fixed ring

67: support surface 68: securing member

70: fixed flange 72: clamp-in tension member

It is an object of the present invention to provide a fastening device of the type mentioned at the outset, which simply and cost-effectively eliminates the above mentioned disadvantages.

This object is achieved by a fixing device having the features of claim 1.

The fixing device according to the invention comprises a vibration uncoupler at the compressor inlet between the casing portion of the compressor and the filter absorber for connecting the filter absorber to the casing portion of the compressor. With the help of the vibration separator, the filter sound absorber is significantly separated in vibration from the casing portion of the compressor and from the turbocharger. When vibration from the turbocharger or from the compressor is transmitted to the filter sound absorber, the high amplitude of the filter sound absorber is prevented and the early fatigue of the material due to the stress of the material caused by the high vibration is canceled out.

The vibration separator used is preferably a heat resistant, oil resistant, and wear resistant elastomeric member. By doing so, the vibration separator is optimized for use conditions, so that the life of the vibration separator is long. Elastomers (eg Viton, DuPont) ) Or silicone) is known to be very suitable as a vibration separator.

In the installed state, it is advantageous for the vibration separator to have low rigidity in the axial direction of the turbocharger and in the direction transverse to the axial direction of the turbocharger. The stiffness in the axial and transverse directions can be chosen differently as a function of the six natural frequencies of the turbocharger. Low stiffness ensures sufficient vibration separation between the casing part of the compressor and the filter absorber.

Considering the design conditions, choose a vibration separator as smooth as possible. At the very least, however, taking into account the weight of the component and its geometry and the geometry of the connection between the casing and the filter absorber of the compressor, the filter absorber is finally at least about 25% to 50% of the lowest natural frequency of the turbocharger. The rigidity is preferably chosen to have a natural frequency of 40%. When the turbocharger is excited in the natural frequency range, for example by vibration of the engine, the filter absorber vibrates in the supercritical range.

It is particularly advantageous if the vibration separator is in a prestress state. This prevents contact loss between the vibration separator and components and prevents wear and wear on the vibration separator.

It is particularly preferable to configure the vibration separator in the form of an O ring, because in this embodiment, the forces absorbed by the connecting portion are distributed over the entire circumference of the O ring.

In the case where the oscillating separator in the form of an O ring is broken, it is advantageous to provide a securing element which prevents the coupling between the casing portion of the compressor and the filter sound absorber to be released.

Further preferred embodiments are disclosed in the dependent claims.

Hereinafter, the present invention will be described in more detail with reference to preferred exemplary embodiments shown in FIGS. 1 to 5.

Reference numerals used in the figures and their meanings are described in the description of the reference numerals. Basically, the same parts in the drawings are given the same reference numerals. The described embodiments are examples of the present invention, but the present invention is not limited thereto.

1 is a cross-sectional view showing the turbocharger 12 and the filter absorber 16 fixed at the compressor inlet 14 of the turbocharger 12 along the longitudinal axis 10 of the turbocharger. The turbocharger 12 comprises a conventional structure, that is, a compressor 18 and a turbine 20, the rotors 22 and 24 of which are arranged at a predetermined distance from each other on the common shaft 26. The turbocharger 12 includes a turbocharger casing 28 comprising a plurality of casing portions, such as a turbine casing 29, bearing casing 30, and compressor casing 27, which are themselves comprised of a plurality of casing portions. Equipped. The shaft 26 is mounted in a bearing casing 30 between the turbine rotor 24 and the compressor rotor 22. The turbocharger 12 is fixed to the bracket 34 of the engine (not shown) by the fixing table 31. In order to reduce the noise emission, the filter sound absorber 16 is fixed to the casing portion 32 of the compressor 18 at the compressor inlet 14.

The filter absorber 16 and the casing portion 32 of the compressor 18 are firmly connected to each other via the fixing device 36. In this example, the stationary device 36 comprises a first stationary orifice 38, which is arranged in a circular line about the longitudinal axis 10 of the turbocharger and in the casing portion of the compressor 18. Is provided. The first fixed orifice 38 is provided with a thread. In addition, the fixing device 36 comprises a second fixing orifice 42, which is arranged in the flange 40 of the filter sound absorber 16 and is connected with the first fixing orifice 38. Can match coaxially. Similarly, the fastening device 36 comprises a fastening member 44, which in this example is configured as a screw and passes through the second fastening orifice 42 to the first fastening orifice 38. Screwed, the filter sound absorber 16 is firmly connected to the casing portion 32 of the compressor 18.

As shown in Fig. 1, the distance between the holder 31 and the filter absorber 16 is very large. Vibration transmitted from the engine (not shown) to the turbocharger 12 through the bracket 34 and the stand 31 and the natural vibration of the turbocharger are transmitted to the filter sound absorber 16 through the rigid fixing device 36. . Due to the considerable distance between the holder 31 and the filter absorber 16, the amplitude in the filter absorber 16 is greatest. This is already accompanied by the above mentioned disadvantages.

2 to 4 respectively show fastening devices 36 according to the invention. Each of the fixing devices 36 is arranged in a casing portion 32 of the compressor 18 and has a threaded first fixing orifice 38 and a screw-type fixing screwed to the first fixing orifice 38. Member 44. The first fixed orifice 38 is preferably arranged in a ring about the longitudinal axis 10 of the turbocharger in a plane perpendicular to the longitudinal axis 10 of the turbocharger. The direction in which the longitudinal axis 10 of the turbocharger is located is indicated by arrow (a) in each figure. Ideally, the ring is a circular ring, with a plurality of first fixed orifices 38 distributed evenly on the ring. In addition, the fixing device 36 according to the invention comprises a vibration separator 46 arranged between the casing portion 32 of the compressor 18 and the filter sound absorber 16. The vibration separator 46 is made of an elastomer having low rigidity in the axial direction of the turbocharger 12 and in the direction transverse to the axial direction of the turbocharger 12. The stiffness is selected such that the natural frequency of the filter absorber 16 is at least about 40% of the lowest natural frequency of the turbocharger 12. In particular, the stiffness depends on the geometry of the component, the weight of the component, and the shape of the fastening device 36.

In addition, the fixing device 36 shown in FIG. 2 includes a second fixing orifice 42 which is arranged to coincide with the first fixing orifice 38 in the flange 40 of the filter absorber 16. The inner diameter of the second fixed orifice 42 is larger than the inner diameter of the first fixed orifice 38. The vibration separator 46 has two separating members 47 composed of an elastomer, the two separating members 47 forming a hollow cylinder 48 shape, and one end of the two separating members has a radius The flange portion 50 protruding in the direction outward is provided. The outer diameter of the hollow cylinder 48 is approximately equal to the inner diameter of the second fixed orifice 42. The hollow cylinder 48 composed of the separating members 47 is inserted into the second fixed orifice 42 from both sides, so that the flange portions 50 of these separating members project laterally beyond the edge of the fixed orifice 42 and are flanged. Cover a portion of 40. The length of the hollow cylinder 48 is preferably selected such that when the flange portion 50 abuts the edge of the second fixed orifice 42, the end faces on the flangeless side of this cylinder contact each other. It is preferable that the separating member 47 be configured in the same manner and manufactured more simply. However, the separating member may be configured differently, in particular, the shape of the flange portion 50 may be configured differently according to the shape of the second fixed orifice 42 and / or the shape of the flange 40. The hollow cylinder 48 together forms an orifice 52 in the vibration separator 46 to receive the stationary member 44. Thus, a spacer bush 54 is inserted into the orifice 52 so that a predetermined prestress can be applied to the vibration separator 46, which spacer bush also forms a hollow cylinder, and one end of the spacer bush Is provided with a bush flange 58 which projects radially outward. The hollow cylinder 56 of the spacer bush 54 is arranged in the orifice 52 to surround the fixing member 44. The bush flange 58 abuts the flange portion 50 located on the sound absorber side.

In order to fix the filter sound absorber 16 to the casing portion 32 of the compressor 18, the separating member 47 is first inserted into the second fixed orifice 42 of the flange 40 of the filter sound absorber 16. do. The spacer bush 54 is inserted into the orifice 52 formed by the separating member 47. Thereafter, the second fixed orifice 42 and the first fixed orifice 38 coincide with each other and are screwed together by the threaded fixing member 44. The length of the hollow cylinder 58 of the spacer bush 54 is shorter than the depth of the orifice 52. That is, when the bush flange of the spacer bush 54 inserted into the orifice 52 is in contact with the flange portion 50 of the separating member 47 located on the sound absorber side, the end face on the flangeless side of the hollow cylinder 58 And a gap exists between the edge of the first fixed orifice 38 and the first fixed orifice 38. By tightly tightening the screw 44 which is a fixing member, the spacer bush 54 is in contact with the edge of the first fixing orifice 38, and the separating members 47 are pressed against each other. The separating member 47 is in a predetermined prestressed state, and as a result, when a load is applied to the connection portion formed by the fixing device 36 between the casing portion 32 and the filter sound absorber 16 of the compressor 18, The various components are always in contact with the vibration separator 46, so that the vibration separator 46 is protected from irregular loads.

Ten stationary orifices 38, 42 are evenly distributed about the longitudinal axis 10 of the turbocharger, the weight of the filter sound absorber 16 is about 380 kg, and the axial and radius of all vibration separators 46. In the case where the stiffness in the direction is about 5000 N / mm to 15000 N / mm, vibration separation in which the natural frequency of the filter absorber 16 is about 40% of the natural frequency of the turbocharger 12 is obtained.

In addition to the above-described member, the fixing device 36 shown in FIG. 3 is provided in the member 60 of the filter sound absorber 16 to support the vibration separator 46 and the vibration separator 46 in the form of an O-ring. An annular groove 62 formed and opened radially outward, and two retaining rings 64, 66. The two fixing rings 64, 66 have a hole 68 for receiving the fixing member 44, which hole is coaxial with the first fixing orifice 38 in the casing portion 32 of the compressor 18. Can match. The fixing rings are arranged coaxially and sequentially with one another in the longitudinal direction in contact with the casing portion 32 of the compressor 18. The fixing rings 64, 66 are fixed to the casing portion 32 of the compressor 18 via the threaded fixing member 44. On the inner side in the radial direction, the stationary rings 64, 66 support surfaces 67 supporting the O-rings 46 at angles of about + 30 ° to about + 50 ° and at angles of -30 ° to -50 °, respectively. ) Thus, the support surfaces 67 together also form a kind of annular groove, which is opened radially inward and extends in parallel at a distance from the annular groove 62 in the sound absorber member 60. The diameter on the radially inner side of the stationary rings 64, 66 and the diameter of the annular groove 62 in the member 60 of the filter absorber 16 are in the form of an O-ring vibration separator 46 arranged therebetween. Is selected to receive prestress when is fixed.

With the filter sound absorber 16 having a weight of about 380 kg and the above configuration, the turbocharger 12 has an axial stiffness of 7000 N / mm to 14000 N / mm and a radial stiffness of 15000 to 40000 N / mm. The natural frequency of the filter sound absorber 16 of about 40% of is obtained.

4 shows another embodiment formed in a manner similar to the fastening device shown in FIG. 3. However, this embodiment further includes a securing member 68 for the fixing device 36. The securing member 68 is arranged axially in contact with the fixing ring 66 adjacent to the filter sound absorber 16, and together with the fixing rings 64, 66, the casing portion 32 with the aid of the fixing means 44. Is fixed to). The securing member protrudes radially inward and outward through the fixing rings 64, 66, and when the O-ring is broken, the member 60 of the filter sound absorber 16 having the annular groove 62 is rearward. By supporting at, the coupling between the casing portion 32 of the compressor 18 and the filter sound absorber 16 is prevented from being released. Like the stationary rings 64 and 66, the securing member may have an annular structure or the like, and may be composed of several pieces of rings, for example.

In another embodiment (not shown) which is almost similar to the fixing device shown in FIG. 3 or 4, the fixing ring 64 adjacent to the casing portion 32 of the compressor 18 is formed integrally with the casing portion 32. .

Another embodiment schematically shown in FIG. 5 is a variation of the embodiment of FIG. 3. Instead of the threaded fastening member 44, the fastening device 36 comprises a fastening member 44 in the form of a tension member 72. Thus, the casing portion 32 of the compressor 18 has a fixed flange 70 instead of the first fixed orifice 38. The stationary rings 64, 66 also do not have any stationary orifices 38. The retaining rings 64, 66 are fixed to the casing portion 32 of the compressor 18 by the tension member 72, which is a clamp, not by the threaded fixing member 44. Distributed on the circumference to ensure a firm connection between the components.

In the above arrangement of the fixing device 36 with the oscillating separator 46 in the form of an O-ring, it can be joined to each other for assembly purposes, for example by means of tension members or auxiliary holes which are clamps and auxiliary screws entering the holes. The stationary rings 64, 66 and the vibration separator 46 in the form of an O-ring are first mounted on the filter sound absorber 16 in advance. Thereafter, the filter sound absorber 16 is fixed to the casing portion 32 and the turbocharger 12 of the compressor 18 by the fixing members 44 through the fixing rings 64, 66.

By the filter sound absorber 16 having the weight of about 380 kg and the above configuration, the axial stiffness of the vibration separator 46 and the axial stiffness of 7000 N / mm to 4000 N / mm and the 15000 to 40000 N / of the vibration separator 46 With a radial stiffness of mm, the natural frequency of the filter sound absorber 16 of about 40% of the turbocharger 12 is achieved.

There may be various variations and combinations of the fastening device 36 described above. Thus, for example, the tensioning member 72 and the threaded fixing member 44, which are clamps, may be used together. The second fixed orifice 42 may be arranged in another member of the filter absorber 16 adjacent to the compressor inlet 14, instead of being arranged in the flange 40 of the filter absorber 16. Instead of the first fixed orifice 38 in the casing portion 32 of the compressor 18, a thread may be provided in the second fixed orifice 42 in the filter absorber 16. The first fixed orifice 38 in the casing portion 32 of the compressor 18 may be arranged in the flange of the casing portion 32. Thereafter, the threaded fixing member 44 may be screwed from the side of the compressor instead of the side of the filter sound absorber 16.

Claims (14)

A fixing device for detachably fixing a filter sound absorber to a casing portion of a compressor belonging to a turbocharger for an internal combustion engine, the filter sound absorber being fixed to a compressor inlet with the aid of a fixing member, The fixing device 36 comprises a vibration separator 46 arranged between the casing portion 32 of the compressor 18 and the filter absorber 16, when the filter absorber 16 is turbocharged. A stationary device characterized in that it vibrates at a different frequency than the casing (28). 2. A fixing device according to claim 1, wherein the vibration separator (46) is a wear resistant, heat resistant, and oil resistant elastomeric member which is preferably composed of an elastomer. The vibration separator (46) according to claim 1 or 2, wherein the vibration separator (46) has low rigidity in the direction transverse to the axial direction (10) of the turbocharger (12) and the axial direction (10) of the turbocharger (12). Fixing device, characterized in that. The vibration separator (46) according to any one of claims 1 to 3, wherein at least the lowest natural frequency of the separated filter absorber (16) is approximately 40% of the lowest natural frequency of the turbocharger (12). Fixing device, characterized in that it has a rigidity to correspond. A fixing device according to any of the preceding claims, characterized in that the vibration separator (46) is mechanically prestressed. In any one of the preceding claims, fixing orifices (42, 38) corresponding to each other for receiving the fixing member (44) are provided in the casing portion (32) of the filter sound absorber (16) and the compressor (18), In each case the vibration separator 46 can be inserted into the fixed orifice 42 of the filter sound absorber 16, the vibration separator 46 itself being an orifice 52 for receiving the fixing member 44. Fixing device comprising a. 7. The vibration separator (46) according to claim 5 or 6, wherein the vibration separator (46) preferably comprises two separating members (47), which are identically constructed, the two separating members having a hollow cylinder with a flange portion (50). 56, the flange portion 50 protrudes from the hollow cylinder 56 at one end of the separating member and is preferably in the form of a circular disk, the hollow cylinder 56 being the filter absorber 16 in both directions. Can be inserted into the second fixing orifice 42 of the orifice 52 together to receive the fixing member 44, the flange portion 50 being laterally past the edge of the fixing orifice 42. By projecting to the flange portion 50, the flange portion 50 forms a buffer between the head of the fixing member 44 and the filter absorber 16 or between the casing portion 32 and the filter absorber 16 of the compressor 18. Fixed characterized in that Value. 8. The prestress is applied to the vibration separator 46 in a predetermined manner by the spacer bush 54, and the spacer bush vibrates. Fixing device, characterized in that it can be inserted into the orifice (52) of the separator (46). 6. The annular groove according to any one of claims 1 to 5, wherein the annular groove (62) is arranged in the member (60) adjacent to the compressor inlet (14) of the filter sound absorber (16) and opens radially outward. Further provided are two fixing rings 64, 66 with radially inner sides extending parallel from the 62 at a predetermined radial distance, and the vibration separator 46, on the one hand, has a filter sound absorber ( 16 is configured in the form of an O-ring supported by an annular groove 62 on the other hand, by two fixing rings 64, 66, the two fixing rings 64, 66 being coaxial in the axial direction. And arranged in turn from one another and connected to the casing portion (32) of the compressor (18) by means of a fixing member (44). 10. Prestress is applied to the vibration separator (46) via the retaining rings (64, 66), and the retaining rings (64, 66) are preferably between about + 30 ° and + 50 °. Fixing device, characterized in that for supporting the vibration separator (46) in the form of an O ring at an angle and an angle of -30 ° to -50 °, respectively. The fixing device according to claim 9 or 10, characterized in that the fixing ring (64) adjacent the casing portion (32) of the compressor (18) is formed integrally with the casing portion (32) of the compressor (18). 12. The method according to any one of claims 9 to 11, wherein the coupling between the casing portion 32 of the compressor 18 and the filter sound absorber 16 is prevented from being released when the vibration separator 46 is broken. And a securing member (68) is provided. 13. The securing member (68) according to claim 12, wherein the securing member (68) is fixed to at least one of the stationary rings (64, 66) and / or the casing portion (32) of the compressor (18), and the vibration separator (46) is broken. In the case, the fixing device characterized by supporting the back of the member (60) of the filter sound absorber (16) provided with the annular groove (62) from the side of the filter sound absorber (16). A turbocharger for supplying an internal combustion engine having a filter sound absorber (16) arranged at the compressor inlet (14) and detachably connected to the casing portion (32) of the compressor (18) of the turbocharger (12). Turbocharger, characterized in that a fixing device (36) according to any one of the preceding claims is provided for securing a filter sound absorber (16) to a casing portion (32) of a compressor (18).