KR19990008477A - Exhaust turbocharger - Google Patents

Abstract

A double wall partition 4 is arranged between the turbine 3 and the compressor 2 in the exhaust turbocharger. Radial ribs 12 and webs 14 are provided for the purpose of reinforcing the inner wall 13. The space 8, 11 bounded by the compressor 2 and the partition 4 makes the heat transfer to the compressor more difficult compared to the prior art, and thus the operating cycle of the compressor wheel is increased. The axial thrust is reduced by the circumferential slot 15 in the inner wall 130 of the partition 4 which reduces the increased pressure under the sealing strip 7.

Description

Exhaust turbocharger

1 is a partial longitudinal sectional view of an exhaust turbocharger;

2 is a partial view showing a partition with a sealing strip.

3 is a partial view showing the partition together with the kabapan.

4 is a cross section through a double wall partition (web and rib).

Explanation of symbols for the main parts of the drawings

1 .. Shaft 2 ..... Compressor

3 ..... Turbine 4 ...... Partition

5 ...... cover 6 ..... exhaust space

7 ...... Sealing strip 8 ..... Space between compressor and partition

9 ..... guide bushing 10 ..... protective shaft bushing

11 ...... Intermediate space 12 ...... Radial rib

13 ....... Inner Wall 14 ..... Web

15 ...... Circumferential slot 16 ..... Turbine disc

17 ..... Fastening Elements

The present invention relates to an exhaust turbocharger in which a partition is arranged between a compressor and a turbine to shield hot exhaust gases.

Such exhaust turbochargers are known. Up to now, single-wall partitions have been disposed between the compressor and the turbine mounted on a conventional shaft, which serve to shield the hot gas from the compressor to the turbine. Because of this, only a very small amount of exhaust gas is exchanged in the intermediate space and thus acts as a barrier layer, so that the intermediate space is produced by a flat kabapan and enhances this effect. Guide bushes are used during assembly for guiding purposes (support of the partitions) so as not to damage the sealing strip between the compressor and the partitions (labyrinth seals). In this case, the shaft rubs against the partition and can be very damaged.The guide bush is made of aluminum to limit or prevent this damage.

In addition, the partition and protective shaft bushing direct the leaking air that emerges through the gap in the labyrinth chamber through the compressor, shaft and turbine disc into the gas outlet housing. Free space is arranged below the labyrinth seal between the compressor and the partition. The leaking air cools the compressor, shaft and turbine disc. It prevents the exhaust gas from reaching the compressor and is therefore referred to as containment air.

Containment air between the compressor and the partition tends to rotate with the compressor and thus raise the pressure just below the seal. Elevated pressures increase the axial thrust on the bearings.

The increase in axial thrust can be prevented by installing ribs on the partitions of the above mentioned free space. The ribs have the disadvantage of increasing the dissipation of heat to the extruder wheels, although they reduce the axial thrust to the bearings, leading to vortices which lead to a reduction in working life.

The present invention attempts to avoid all these drawbacks. Its purpose is to achieve a low temperature on the compressor wheel at the same time as a small axial thrust in the case of an exhaust turbocharger of the type mentioned at the outset without supplementing additional parts, thus achieving an increased operating time compared with the prior art. .

It consists of a compressor and a turbine arranged on a conventional shaft, and a partition is disposed between the compressor and the turbine, separated from the exhaust gas space of the turbine by a cover plate disposed between the compressor and the turbine, and a sealing strip (labry's seal). Is installed between the compressor and the partition, in the exhaust turbocharger with a guide bushing with a securing element for supporting the partition on the shaft and a protective wave bush arranged in a space just below the sealing strip between the compressor and the partition. The partition is enlarged by the existing cross section of the rib, and the partition arranged in the radial rib is configured in the double wall type so that an additional intermediate space exists, and the exhaust turbocharger in which the slots are installed facing the compressor roundly in the inner wall of the double wall partition According to the present invention.

If the inner wall is connected to the partition by the web, it is a special solution.

The advantage of the present invention is that, in comparison with the prior art, it is possible to achieve low temperatures and small axial thrust in the compressor wheel in the case of exhaust turbochargers without additional supplementary parts, which also leads to an increase in the action time.

A more complete assessment of the invention and its attendant advantages will be readily appreciated as the invention becomes more clearly understood by reference to the following detailed description taken in conjunction with the accompanying drawings.

Only elements essential to understanding the invention are shown. Parts of the device that are not shown are, for example, the inlet part of the compressor housing or the exhaust housing of the turbine with the flue gas pipe and the furnace. The flow direction of the working medium is indicated by the arrow.

According to FIG. 1, the exhaust turbocharger according to the present invention comprises a compressor 2 mounted on a conventional shaft and a turbine 3, and a double wall partition 4 between the compressor 3 and the turbine 3. Is placed. The partition 4 has a main function of shielding the high-temperature exhaust gas from the compressor 2 to the turbine 3. The kabapan 5, which is screwed into the partition (FIG. 3) and thus reduces the exhaust gas space 6, is made so that the exhaust gas is exchanged only a very small amount in the intermediate space and thus acts as a barrier layer. By strengthening this action.

During assembly of the exhaust turbocharger, the guide bush 9 acts as a guide (support of the partition 4) so as not to damage the sealing strip (labry's seal) between the compressor 2 and the partition 4. In the event of a failure of the bearing (radiation enlargement), the shaft 1 will pass through the partition 4 and thus become very damaged.

The free space 8 between the compressor 2 and the partition 4 is enlarged by a rib section (existing conventionally as a prior art). As a result, vortex formation is prevented and heat dissipation to the compressor wheel becomes more difficult. In this configuration, the increased thrust is created by the elevated pressure by the circulating flow of air in the space 8 below the sealing strip 7 given by the single-wall partition according to the prior art. In the case of an exhaust turbocharger according to the invention, this air takes place in the intermediate space 11, in which it expands in the circumferential slot 15 (FIG. 2) in the inner wall. This prevents the pressure rise that creates increased thrust.

Containment air flows between the compressor 2 and the space 8 via the sealing strip 7, as well as to the shaft 1 via the intermediate space 11 in an enhanced type and thereafter a protective shaft bushing ( It passes between the 10 and the turbine disc 16 and flows into the exhaust gas space 6 of the turbine 3. The containment of the exhaust gas and the cooling of the shaft 1 in relation to the compressor are ensured.

The radial ribs 12 are installed in the intermediate space 11 of the inner wall 13 (FIG. 4). As a result, the wall 13 is strengthened and also prevents circulating flow in the intermediate space 11. The inner wall 13 is connected to the partition 4 via the web 14.

The guiding bush 9 is secured by the securing element 17 and also additionally assures an interrelated sealing of the two spaces 8 and 11 with the above mentioned functions, so that only a small amount of containment air is interspaced. The space 8 can be reached from (11).

The two spaces 8 and 11 make the heat transfer to the compressor 2 substantially more difficult compared to the prior art. The low temperature thus obtained leads to an increase in the working life of the compressor wheel. At the same time, the circumferential slot 15 which reduces the increased pressure just under the sealing strip 7 reduces the axial thrust.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

Claims (2)

Composed of a compressor (2) and a turbine (3) arranged on a conventional shaft (1), the partition (4) is arranged between the compressor and the turbine, and by the cover plate (5) the exhaust gas space of the turbine (3) ( Separate from 6), a sealing strip (labry's seal) 7 is installed between the compressor 2 and the partition 4, just below the sealing strip 7 between the compressor 2 and the partition 4 In the exhaust turbocharger in which the space 8 is arranged and the guide bush 9 having the fixing element 17 for supporting the partition 4 on the shaft and the protective wave bush 10 is arranged, the free space is conventionally used. Exhaust turbocharger, which can be enlarged by the cross section of the existing ribs, the partition with radial ribs arranged in a double-wall type, so that an additional intermediate process is arranged and the slots are installed facing the compressor roundly in the inner wall of the partition. . 2. Exhaust turbocharger according to claim 1, characterized in that the inner wall (13) is connected to the partition (4) by a web (14).