US20170328376A1

US20170328376A1 - Compressor including a sealing channel

Info

Publication number: US20170328376A1
Application number: US15/532,391
Authority: US
Inventors: Alister Clay; Johannes Wegele; Konstantinos Stergiaropoulos; Simon Klink; Ulrich Michels
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2014-12-03
Filing date: 2015-10-08
Publication date: 2017-11-16
Also published as: EP3227560B1; CN107002695A; DE102014224757A1; WO2016087095A1; EP3227560A1; KR20170091617A; KR102476421B1; CN107002695B

Abstract

A compressor, which includes a housing and a rotor, in which the rotor includes a compressor wheel on at least one side, a compressor chamber being formed between the compressor wheel and the housing, the rotor being rotatably supported, an annular sealing channel being formed between the rotor and the housing, the sealing channel being routed from the compressor chamber to an area having a lower pressure, a connecting channel being routed from an area having a higher pressure to a first section of the sealing channel.

Description

FIELD OF THE INVENTION

The present invention relates to a compressor.

BACKGROUND INFORMATION

According to the related art, a turbo compressor is discussed in DE 10 2012 012 540 A1, which includes a first compressor stage having a first compressor wheel and a second compressor stage having a second compressor wheel. The first and second compressor wheels are situated on a shared shaft, and the shaft is supported contact-free. A sealing gap is formed between the first and second compressor stages. A groove is provided in the housing to seal the sealing gap. The compressor wheel also includes a flange, which engages with the groove.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a compressor, which has an improved sealing of the sealing channel.
The object of the present invention may be achieved by the compressor as described herein.
Other specific embodiments of the present invention are indicated in the further descriptions herein.
The proposed compressor has the advantage that the formation of the sealing channel between a compressor chamber and an area having a lower pressure is improved. In particular, an axial force on the rotor is reduced. Leaks via the sealing channel are also reduced. In addition, the rotational resistance of the rotor is relatively low. These advantages are achieved in that a connecting channel is routed from an area having a higher pressure to a first section of the sealing channel. The pressure in the first section of the sealing channel is increased due to the connecting channel. Leaks are reduced thereby.
In one specific embodiment, the connecting channel is routed from the compressor chamber to a first section of the sealing channel. A high pressure may thereby be guided to the first section of the sealing channel.
In another specific embodiment, the connecting channel is routed from a second section of the sealing channel to the first section of the sealing channel, the first section being situated downstream in the direction of a lower pressure area with respect to the second section.
Depending on the specific embodiment selected, the rotor includes a first compressor wheel on a first side and a second compressor wheel on a second diametrically opposed side. With the aid of this specific embodiment, a low pressure stage and a high pressure stage may be implemented with the aid of the two compressor wheels. The sealing channel is formed between the high pressure stage and the low pressure stage. In this specific embodiment, a sealing action between the two compressor chambers may again be achieved with the aid of the connecting channel.
Depending on the specific embodiment selected, the compressor wheel may be supported contact-free in the housing, the sealing channel being formed in the area of the bearing.
In another specific embodiment, a sealing element is provided, which represents at least one side of a section of the sealing channel. The sealing element is formed from a softer material than the housing or the compressor wheel. An improved sealing action may thus be achieved.
In another specific embodiment, the sealing element is formed on the housing, a radial recess being formed on the sealing element, and a radial web being formed on the rotor, which engages with the recess of the sealing element. An improved sealing action is thus provided.
In another embodiment, the connecting channel is formed in the housing.
In another embodiment, the connecting channel is at least partially, in particular completely, formed in the sealing element. An easier manufacture is thus possible.
In another embodiment, the sealing element includes multiple connecting channels. A larger cross section may be achieved thereby, while maintaining a more uniform pressure distribution.
In another embodiment, the sealing element is connected to the housing, the sealing element projecting into a circumferential recess of the rotor, at least one section of the sealing channel being formed between the sealing element and the rotor.
In another embodiment, the connecting channel is formed in the rotor.
Depending on the specific embodiment selected, the compressor may be configured as a turbo compressor.
The present invention is explained in greater detail below on the basis of the figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows one first specific embodiment of a compressor, including a rotor having a compressor wheel on one side.

FIG. 2 shows another specific embodiment of the compressor, including a rotor having a compressor wheel on one side.

FIG. 3 shows one specific embodiment of a compressor, including a rotor having two compressor wheels.

FIG. 4 shows another specific embodiment of the compressor, including a rotor having two compressor wheels.

FIG. 5 shows one specific embodiment of a rotor, which is supported on a shaft.

FIG. 6 shows another specific embodiment of the rotor, which is supported on a shaft.

FIG. 7 shows one specific embodiment of a compressor, a sealing element being formed on the rotor.

FIG. 8 shows another specific embodiment of the compressor, a sealing element being formed on the rotor.

FIG. 9 shows one specific embodiment of a compressor, a sealing element being formed on the housing.

FIG. 10 shows another specific embodiment of the compressor, a sealing element being formed on the housing.

FIG. 11 shows another specific embodiment of a compressor, including a sealing element having a connecting channel.

FIG. 12 shows a side view of the sealing element from FIG. 11.

FIG. 13 shows another specific embodiment of a compressor, including a connecting channel in the sealing element.

FIG. 14 shows a schematic partial cross section of another specific embodiment of a sealing element, including a connecting channel whose inlet opening and outlet opening are situated on a same first side surface.

FIG. 15 shows a schematic partial cross section of another specific embodiment of a sealing element, which has the inlet opening and the outlet opening on different side surfaces.

DETAILED DESCRIPTION

FIG. 1 shows a schematic cross section of one part of a compressor 1, which includes a housing 2 and a rotor 3. Rotor 3 is rotationally symmetrically formed with respect to a rotation axis 4. Rotor 3 includes a first compressor wheel 5 having moving blades on a first side. A first compressor chamber 6 is formed between first compressor wheel 5 and housing 2. In the illustrated exemplary embodiment, first compressor chamber 6 includes an annular, first intake channel 7. When rotor 3 rotates around rotation axis 4, a medium is sucked in via first intake channel 7, compressed by first compressor wheel 5 and discharged via a first compression channel 8. A sealing channel 11, which connects first compressor chamber 6 to an area having a lower pressure 12, is formed between a radial exterior side 9 of rotor 3 and an assigned interior side 10 of housing 2. A connecting channel 20 is also routed from compressor chamber 6 or from an initial area of compression channel 8 to a first section 21 of sealing channel 11. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in housing 2. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof.
Rotor 3 may be rotatably supported via a contact-free bearing in housing 2, for example in the area of sealing channel 11.
Depending on the specific embodiment selected, rotor 3 may also be connected to a shaft, which is not illustrated and which is situated in rotation axis 4 and is rotatably supported on housing 2.
FIG. 2 shows another specific embodiment of the compressor from FIG. 1, connecting channel 20 being routed from a second section 22 of sealing channel 11 to first section 21 of the sealing channel. Second section 22 is situated in the initial area of the sealing channel, adjacent to first compressor chamber 6. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in housing 2. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11, or in the third quarter of the length thereof.
FIG. 3 shows one specific embodiment of a compressor 1, which is configured according to the compressor from FIG. 1, rotor 3, however, including a second compressor wheel 13 having second moving blades on a second side. A second compressor chamber 14 is also formed between second compressor wheel 13 and housing 2. Second compressor chamber 14 furthermore includes a second intake channel 15. A second compression channel 16 is also provided in housing 2. Second compressor wheel 13 is rotationally symmetrically formed with respect to rotation axis 4. Second compressor chamber 14 is connected to first compressor chamber 6 via sealing channel 11. In addition, second intake channel 15 may be connected to first compression channel 8 via a line, which is indicated schematically by an arrow. In this way, two compressor stages may be implemented with the aid of one rotor 3 in a compressor 1. A precompression of the medium is achieved by first compressor wheel 5, a second, higher compression of the precompressed medium being achieved by second compressor wheel 13, the medium being subsequently discharged via second compression channel 16. A connecting channel 20 is also routed from second compressor chamber 14 or from an initial area of second compression channel 16 to a first section 21 of sealing channel 11. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in housing 2. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof, starting from the side of second compressor chamber 14.
FIG. 4 shows one specific embodiment of a compressor 1, which is configured according to the compressor from FIG. 3, connecting channel 20, however, being routed from a second section 22 of sealing channel 11 to first section 21 of sealing channel 11. Second section 22 is situated in the initial area of sealing channel 11, adjacent to second compressor chamber 14. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in housing 2. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof, starting from second compressor chamber 14.
FIG. 5 shows a schematic representation of one specific embodiment of a compressor 1 according to FIG. 2, including a rotor 3 having two compressor wheels 5, 13, which are situated on diametrically opposed sides. In this specific embodiment, rotor 3 is rotatably supported on housing 2 via a shaft 19. Similarly, the specific embodiment from FIG. 1, which includes a rotor 3 having only one first compressor wheel 5, may also be supported on housing 2 via a corresponding shaft 12. In addition, a connecting channel 20 is routed from second compressor chamber 14 of second compression channel 16 to a first section 21 of sealing channel 11. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in rotor 3. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof, starting from the side of second compressor chamber 14.
FIG. 6 shows a schematic representation of another specific embodiment of a compressor 1 according to FIG. 5, connecting channel 20, however, being routed from a second section 22 of sealing channel 11 to first section 21 of the sealing channel. Second section 22 is situated in the initial area of the sealing channel, adjacent to second compressor chamber 14. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in rotor 3. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof, starting from second compressor chamber 14.
FIG. 7 shows a schematic representation of the embodiment of the compressor from FIG. 3, an annular sealing element 17, which engages with an annular recess 18 of housing 2, being provided on rotor 3 in the area of sealing channel 11. Sealing element 17 is formed, for example, from a different material than rotor 3. In particular, a softer material may be used to form sealing element 17 for the purpose of improving the desired sealing function. For example, sealing element 17 may be made from a plastic material. In a compressor 1, which includes a rotor 3 having only one first compressor wheel 5, sealing element 17 may also be provided according to the specific embodiment from FIG. 1. A connecting channel 20 is also routed from second compressor chamber 14 or from an initial area of second compression channel 16 to a first section 21 of sealing channel 11. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in housing 2. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof, starting from the side of second compressor chamber 14. For example, first section 21 may be situated diametrically opposed to the end face of sealing element 17.
FIG. 8 shows another embodiment of the compressor from FIG. 7, connecting channel 20 being routed from a second section 22 of sealing channel 11 to first section 21 of the sealing channel. Second section 22 is situated in the initial area of the sealing channel, adjacent to second compressor chamber 14. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in housing 2. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof, starting from second compressor chamber 14. For example, first section 21 may be situated diametrically opposed to the end face of sealing element 17.
Compressor 1 from FIG. 1, which includes a rotor 3 having only one first compressor wheel 5, may also include a sealing element 17 and a recess 18 according to FIG. 8.
FIG. 9 shows another specific embodiment of the compressor from FIG. 3, an annular sealing element 17 being formed on an interior side 10 of housing 2. Sealing element 17 engages with an annular second recess 18 on exterior side 9 of rotor 3. A connecting channel 20 is also routed from second compressor chamber 14 or from an initial area of second compression channel 16 to a first section 21 of sealing channel 11. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in rotor 3. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof, starting from the side of second compressor chamber 14. For example, first section 21 may be situated diametrically opposed to the end face of sealing element 17.
FIG. 10 shows another specific embodiment of the compressor, which is essentially configured according to FIG. 9, connecting channel 20, however, being routed from a second section 22 of sealing channel 11 to first section 21 of the sealing channel. Second section 22 is situated in the initial area of the sealing channel, adjacent to second compressor chamber 14. First section 21 is situated, for example, in the middle of sealing channel 11. Connecting channel 20 is formed in rotor 3. Depending on the embodiment selected, the first section may also be situated in the second quarter of the length of sealing channel 11 or in the third quarter of the length thereof, starting from second compressor chamber 14. For example, first section 21 may be situated diametrically opposed to the end face of sealing element 17.
FIG. 11 shows a partial detail of another specific embodiment of a compressor 1, which is essentially configured according to FIGS. 9 and 10, the high pressure side, however, being illustrated on the left and the low pressure side being illustrated on the right. Connecting channel 20 is also formed in sealing element 17. Depending on the specific embodiment selected, multiple connecting channels 20 are formed in sealing element 17. Sealing element 17 projects into recess 18 of rotor 3. Connecting channel 20 includes an inlet opening 23 and an outlet opening 24. In the exemplary embodiment illustrated, inlet opening 23 is situated in the area in which second compressor chamber 14 is connected to sealing channel 11. Outlet opening 24 is situated on a radial, inner end face 29 of sealing element 17. Depending on the specific embodiment selected, the cross-sectional surface of connecting channel(s) 20 may be larger than the cross-sectional surface of sealing channel 11. In this way, a greater hydraulic pressure is achieved in sealing channel 20, in particular at outlet opening 24 with respect to the pressure in sealing channel 11 in the area of outlet opening 24. Depending on the specific embodiment selected, however the cross-sectional surface or connecting channel(s) 20 may also be smaller than the cross-sectional surface of sealing channel 11, so that a pressure present in sealing channel 11 in the area of outlet opening 24 is greater than or equal to the pressure present in connecting channel 20 in the area of outlet opening 24.
FIG. 12 shows a schematic representation of a side view of sealing element 17 having an annular disk-shaped design, which includes multiple connecting channels 20. Connecting channels 20 are distributed radially around the annular shape of sealing element 17. Section A-A corresponds to the section in FIG. 11.
FIG. 13 shows a partial detail of another specific embodiment of a compressor 1, which is configured according to FIG. 11, an inlet opening 23 of connecting channel 20, however, having a greater distance from rotation axis 4 than a second inlet opening 25, via which second compressor chamber 14 opens into sealing channel 11, viewed in the radial direction. Second inlet opening 25 is configured in the form of a slit opening running radially around rotation axis 4. In this specific embodiment, inlet opening 23 is essentially situated at the same radial distance from rotation axis 4 as second outlet opening 26, via which sealing channel 11 opens into first compressor chamber 6. Second outlet opening 26 is configured as a radially circumferential slit opening.
As already described with respect to FIG. 11, sealing element 17 from FIG. 13 may also include multiple connecting channels 12, as is clearly illustrated in FIG. 12.
FIG. 14 shows a cross section of another specific embodiment of a sealing element 17. The cross section passes through rotation axis 4. In this specific embodiment, outlet opening 24 of connecting channel 20 is formed on a first side surface 27, on which inlet opening 23 is also formed. First side surface 27 faces the high pressure side. Depending on the specific embodiment selected, outlet opening 24 may be situated in the area of second inlet opening (25, FIG. 13). In addition, depending on the specific embodiment selected, outlet opening 24 may be situated between second inlet opening (25, FIG. 13) and radial end face 29 of sealing element 17 and thus in the area of a lowest point of recess 18. Likewise, multiple connecting channels 20 may be provided in the specific embodiment from FIG. 14, as was already explained on the basis of FIG. 12.
FIG. 15 shows a partial cross section of another specific embodiment of a sealing element 17 of a compressor 1, which is situated in a compressor 1, for example according to FIGS. 11 and 13. In this specific embodiment, inlet opening 23 of connecting channel 20 is situated on first side surface 27, which faces the high pressure side. Inlet opening 23 is connected to second compressor chamber 14 or second compression channel 16. Outlet opening 24 of connecting channel 20 is situated on a second side surface 28 of sealing element 17. Second side surface 28 is situated diametrically opposed to first side surface 27. Second side surface 28 is assigned to the low pressure side and is connected to sealing channel 11. Viewed in the radial direction, outlet opening 24 is not situated at the lowest point of recess 18 with respect to rotation axis 4 but on the side of sealing channel 11, which is routed in the direction of first compressor chamber 6 or first compression channel 8, starting from the lowest point of recess 18. The specific embodiment from FIG. 15 may also have multiple connecting channels 20, as was explained on the basis of FIG. 12.
Depending on the embodiment selected, the connecting channel or connecting channels 20 may be formed in housing 2 and/or in rotor 3 and/or in sealing element 17.
Depending on the selected routing of connecting channel 20, depending on the radial position of inlet opening 23 and/or outlet opening 24, depending on the arrangement of outlet opening 24 on first or second side surface 27, 28 and depending on the cross section of connecting channel 20, different desirable pressure ratios may be set in sealing channel 11. In this way, leaks may be reduced accordingly.

Claims

1-13. (canceled)

14. A compressor, comprising:

a housing; and

a rotor having at least one compressor wheel on one side;

wherein a compressor chamber is formed between the compressor wheel and the housing, the rotor being rotatably supported, an annular sealing channel being formed between the rotor and the housing, the sealing channel being routed from the compressor chamber to an area having a lower pressure and a connecting channel being routed from an area having a higher pressure to a first section of the sealing channel.

15. The compressor of claim 14, wherein the connecting channel is routed from the compressor chamber to a first section of the sealing channel.

16. The compressor of claim 14, wherein the connecting channel is routed from a second section of the sealing channel to the first section of the sealing channel, the first section being situated downstream in the direction of a lower pressure area with respect to the second section.

17. The compressor of claim 14, wherein the compressor wheel is formed on a first side of the rotor, another compressor wheel being formed on a second side of the rotor diametrically opposed to the first side, the additional compressor wheel representing a high pressure stage, and the compressor wheel representing a low pressure stage, the additional compressor wheel being situated in another compressor chamber of the housing, the sealing channel being formed between the compressor chamber and the additional compressor chamber and the connecting channel being routed from an area having a higher pressure to the first section of the sealing channel having a lower pressure.

18. The compressor of claim 14, wherein the rotor is rotatably supported on the housing via a contact-free bearing, and the sealing channel is formed in the area of the bearing.

19. The compressor of claim 14, wherein a sealing element is formed on the rotor and/or on the housing, the sealing element being formed from a softer material than the rotor or the housing, the sealing element representing at least one side of at least one section of the sealing channel.

20. The compressor of claim 19, wherein the sealing element is formed on the housing, a radial recess being formed in the sealing element, a radial web being formed on the rotor, which engages with the recess, and at least one section of the sealing channel being formed between the sealing element and the rotor.

21. The compressor of claim 19, wherein the sealing element is formed on the housing, a radial recess being formed on the rotor, the sealing element engaging with the recess with a radial end face, and at least one section of the sealing channel being formed between the sealing element and the rotor.

22. The compressor of claim 14, wherein the connecting channel is formed in the housing.

23. The compressor of claim 19, wherein the connecting channel is formed at least partially in the sealing element.

24. The compressor of claim 14, wherein there are multiple connecting channels.

25. The compressor of claim 14, wherein the connecting channel is formed in the rotor (3).

26. The compressor of claim 14, wherein the compressor includes a turbo compressor.