GB2103285A - Damping vibrations in compressors for exhaust-driven turbo-superchargers. - Google Patents

Abstract

The compressor-housing rear wall comprises a central disc 50.2, an outer ring 50.1 and a separating ring 52 which surrounds the disc 50.2 in order to damp vibrations and sound transmitted through the housing wall parts. Between separating ring 52 and outer ring 50.1 is a metal bush 53 over which outer ring 50.1 is shrink mounted or friction fitted. The separating ring may be made of vulcanised rubber which adheres to the disc and the bush. In a further embodiment a metal bush is provided both inside and outside the separating ring. <IMAGE>

Description

SPECIFICATION A compressor, particularly for exhaustdriven turbosuperchargers This invention relates to a compressor, particularly for exhaust-driven turbosuperchargers having a compressor housing which encloses the compressor wheel and is fastened by a compressor-housing rear wall to a stator housing for the mounting of the driving shaft, in which respect the compressor-housing rear wall is subdivided into a centric disc and at least one outer ring and having at least one separating ring which deadens vibrations and sound transmitted through solids, which surrounds the centric disc peripherally and which connects the two adjoining housing wall parts to one another. Furthermore, the invention relates to a method of producing a compressor-housing rear wall having a separating ring which deadens vibrations and sound transmitted through solids.

The applicants' German Patent No.

P3036890,2-15 provides for the fact that the separating ring is arranged directly between the centric disc and the outer ring of the compressor-housing rear wall. Fastening of the separating ring directly to the two parts of the compressor-housing rear wall has proved to be a comparatively expensive and complicated operation, particularly because material which is most favourable for forming the separating ring does not form a sufficiently good connection with the parts of the compressor-housing rear wall, which are usually made from aluminium die cast metal, to reliably avoid detachment thereof, resulting from shrinkage of the separating ring material after penetration.

An object of the present invention is, therefore, to provide a method of problem-free mass production of the compressor which ensures that detachment of the separating ring from the connection surfaces is reliably avoided.

With this object in view, the present invention proposes that each separating ring which deadens vibrations and sound transmitted through solids is surrounded by and con nected to a metal bush by compression forces and in that the outer ring is mounted upon the separating ring by a friction fit, or under tension.

This development affords the possiblity of making only a single size of centric disc for compressor-housing rear walls of different sizes. Then, in each case, a separating ring having a metal bush is applied to the centric disc. The various outer rings, corresponding to different sizes of a series of compressor-hous ing rear walls are preferably shrink-mounted onto the appropriate metal bushes.

Provision is also made for the fact that each separating ring which deadens vibrations and sound transmitted through solids is located between two metal bushes, the one of which is connected to the centric disc, and the other of which is connected to the outer ring, each by a friction fit or under tension. This embodiment is more complicated and expensive for mass production, but it offers the possibility of the independent production of a separating ring arranged between two metal bushes. For assembly, both the centric disc and the outer ring are preferably shrink-mounted.

A method of establishing at least one connection, deadening vibrations and sound transmitted through solids, between a centric disc and an outer ring of a compressor-housing rear wall provides for the fact that the outer ring is mounted exactly concentrically of the centric disc so as to leave a gap therebetween for the connection which deadens vibrations and sound transmitted through solids, and in that the material, which deadens vibrations and sound transmitted through solids, is introduced into the gap by pouring, pressing, or the like, and may be vulcanised in situ, in order to form a separating ring. The above-described method results in a substantially pressure-free fitting of the separating ring between the outer ring and the centric disc.

In specific instances, depending on the proposed use of the compressor, it may, however, be desirable for the separating ring to be subject to a certain bias. To this end, the invention provides for the production of a separating ring which is built up in two parts.

In other words, the metal bush is mounted exactly concentrically to the centric disc so as to leave a gap therebetween for the material which deadens vibrations and sound transmitted through solids. The material, which deaden vibrations and sound transmitted through solids, is introduced into the gap by pouring, pressing, or the like, and may be vulcanised in situ, in order to form a separating ring. The outer ring of the compressor-housing rear wall is slipped or shrunk onto the metal bush along with pressing of the material which deadens vibrations and sound transmitted through solids. Thus, the outside diameter of the metal bush may be compressed by a specific defined amount, so that the boundary layer between the separating ring and the metal bush is subjected to a pressure bias, which counters a tendency of the separating ring material to detach from the metal.This pressure bias is propagated through the separating ring to the boundary layer between the centric disc and the separat ing ring, so that the risk of a detachment at this boundary layer may also be obviated.

Finally, the invention provides for a three-part construction, metal bush-separating ring-metal bush, wherein the two metal bushes are mounted exactly concentrically of one another with a gap therebetween for the material which deadens vibrations and sound transmitted through solids. The material, which deaden vibrations and sound transmitted through solids is introduced into the gap by pouring, pressing, or the like an may be vulcanised in situ to form a separating ring, and, on the one hand the inner metal bush is shrunk or mounted under tension onto the centric disc and on the other hand the outer ring of the compressor-housing rear wall is shrunk or mounted under tension onto the outer metal bush.

This three-part construction consisting of metal bush, separating ring and metal bush is particularly advantageous as it may be premounted separately, in order to be able to use it for different series of compressor-housing rear walls, in which respect constructionally different centric discs and outer rings may be combined with one another. This three-part construction may also prove to be advantageous when the material used for the separating ring does not enter into the desired secure bond with the customarily used aluminium material of the compressor-housing rear walls.

As a result of the three-part construction, the metal bushes may be produced from a material which enters into a very intimate connection, not endangered by detachment, with the material of the separating ring.

The invention will be described further, by way of example, with reference to the accompanying drawing, in which: Fig. 1 is a section through a compressorhousing rear wall in accordance with one embodiment of the present invention; Figure 2 is a perspective exploded representation of the same embodiment as shown in Fig. 1; Figure 3 is a partial section through a compressor-housing rear wall in accordance with a further embodiment of the invention; The compressor-housing rear wall 50 shown in Fig. 1 comprises an outer ring 50.1 and a centric disc 50.2, between which is located a separating ring 52 made from a material which deadens vibrations and sound transmitted through solids, as well as a metal bush 53. A compressor-housing rear wall of the same construction is shown in Fig. 2 in a respective exploded representation.

To produce such a compressor-housing rear wall, the outer ring 50.1 and the centric disc 50.2 are produced from aluminium die cast metal and are subjected to a surface processing in order to bring the surfaces, butting against the separating ring 52 and against the metal bush 53, to the requisite accuracy of size. During assembly, the metal bush 53 is initially placed concentrically about the centric disc 50.2, so that a gap is defined for the intermediate layer which deadens vibrations and sound transmitted through solids. A suitable material is introduced into this gap by pouring, pressing or in some other way.

When a rubber material is used, it is subjected to a vulcanising process. In this way, the separating ring 52, which adheres securely on the one hand to the central disc 50.2 and on the other hand to the metal bush 53, is formed. After the formation of the separating ring, the outer ring 50.1 is applied to the metal bush 53 in such a way that the components are held together by tension or compression. In this respect, shrinking of the outer ring 50.1 onto the metal bush 53 is particularly advantageus since, by a careful calibration, care may be taken to ensure that the metal bush 53 is subjected to a specific compression force. The resultant slight deformation brings about a very good and durable connection in the boundary-layer region between the separating ring 52 and the adjoining metal surface so that no detachment is likely to occur upon further operation.

In the further embodiment shown in Fig. 3 there is a three-part construction of connection element comprising an outer metal bush 63, a separating ring 62 and an inner metal bush 64. This construction is more complicated in production than that shown in Figs. 1 and 2, but it affords the advantage that the three-part connection element can be produced independently of the remaining parts of the compressor-housing rear wall. In this respect, the three-part construction is particularly advantageous in that the separating ring 62 may be made of materials which do not normally adhere satisfactorily to an aluminium surface such as the surface of the outer ring 60.1. In this case, however, the material composition for the metal bushes may be selected in such a way that a good adhesion between the separating ring and the metal bushes is ensured.Furthermore, by shrinking the thus formed three-part connection element onto the central disc 60.2 and by subsequently shrinking the outer ring 60.1 thereon care may be taken to ensure that the separating layer 62 is subjected to a pressure loading, whereby detachment of the separating layer 62 from the metal bushes 63, 64 may be reliably prevented.

During production of the aforesaid threepart structure, the inner metal ring 64 is mounted concentrically to the outer metal ring 63 and the resulting gap is filled with the material for the separating ring 62. This material may be introduced by pouring, pressing or in some other way. If rubber is used, it is vulcanised to ensure that the separating ring 62 connects securely to the metal bushes 63, 64.

The embodiments of the invention in accordance with Figs. 1 to 3 furthermore offer the advantage that for a multiplicity of different diameters of compressor-housing rear walls, an identical centric discs may be used for each wall of the entire series. With respect to the changes in the dimensions, merely the outer ring has to be adapted to each individual size of wall. As a result of this measure, the production expenditure can be reduced and the compressor-housing rear wall can be produced comparatively inexpensively.

Claims (7)

1. A compressor, particularly for exhaustdriven turbosupercharger, having a compressor housing which encloses the compressor wheel and is fastened by a compressor-housing rear wall to a stator housing for the mounting of the driving shaft, in which respect the compressor-housing rear wall is subdivided into a centric disc and at least one outer ring, and having at least one separating ring which deadens vibrations and sound transmitted through solids, which surrounds the centric disc peripherally and which connects the two adjoining housing wall parts to one another, characterised in that each separating ring which deadens vibrations and sound transmitted through solids is surrounded by and connected to a metal bush, by compresssion forces and in that the outer ring is mounted upon the separating ring by a friction fit, or under tension.

2. A compressor as claimed in claim 1, characterised in that each separating ring which deadens vibrations and sound transmitted through solids is arranged between two metal bushes, one of which is connected to the centric disc, and the other of which is connected to the outer ring, each by a friction fit or under tension.

3. A method of establishing at least one connection, which deadens vibrations and sound transmitted through solids, between a centric disc and an outer ring of a compressor-housing rear wall as claimed in claim 1, characterised in that the outer ring is mounted exactly concentrically to the centric disc so as to have a gap therebetween for the connection which deadens vibrations and sound transmitted through solids, and in that material, which deadens vibrations and sound transmitted through solids, is introduced into the gap by pouring, pressing or the like, and may be vulcanised in situ, in order to form a separating ring.

4. A method of establishing at least one connection, which deadens vibrations and sound transmitted through solids, between a centric disc and an outer ring of a compressor-housing rear wall as claimed in claim 1, characterised in that the metal bush is mounted exactly concentrically to the centric disc so as to leave a gap therebetween for the connection which deadens vibrations and sound transmitted through solids, in that the material, which deadens vibrations and sound transmitted through solids, is introduced into the gap by pouring, pressing and the like, and may be vulcanised in situ, in order to form a separating ring, and in that the outer ring is slipped or shrunk onto the metal bush.

5. A method of establishing at least one connection, which deadens vibrations and sound transmitted through solids, between a centric disc an an outer ring of a compressorhousing rear wall as claimed in claim 2, characterised in that the two metal bushes are mounted exactly concentrically of one another so as to leave a gap therebetween, in that the material, which deadens vibrations and sound transmitted through solids, is introduced into the gap by pouring, pressing or the like and possibly vulcanised in situ in order to form a separating ring, and in that on the one hand the inner metal bush is shrunk or mounted under tension onto the centric disc and on the other hand the outer ring is shrunk or mounted under tension onto the outer metal bush.

6. A compressor, particularly for exhaust driven turbosuperchargers substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.

7. A method of establishing at least one connection, which deadens vibrations and sound transmitted through solids, between as centric disc and an outer ring of a compressor-housing rear wall substantially as hereinbefore described.