CN111255707B - A kind of compressor - Google Patents

Abstract

The present invention relates to a compressor, belonging to the technical field of compressors, the compressor comprises an end cover, an outer shell, a double-shaft extension motor, a first volute, a first impeller, a second volute and a second impeller, the second end of the outer shell is closed and the first end is through, the end cover covers the first end, the double-shaft extension motor is installed in the outer shell and its rotating shaft extends out of the end cover and the second end, the two ends of the rotating shaft are respectively detachably installed with the first impeller and the second impeller, the first volute is detachably installed on the end cover to form a first compression chamber, the second volute is detachably installed on the second end to form a second compression chamber, the first impeller and the second impeller are respectively located in the first compression chamber and the second compression chamber, the first volute is provided with a first air inlet and a first air outlet, the second volute is provided with a second air inlet and a second air outlet, and the first air outlet is connected to the second air inlet. The compressor can realize two-stage compression of gas, has a simple and compact structure, and the first impeller and the second impeller are both easy to disassemble and assemble, and the cost is low.

Description

A compressor

Technical Field

The invention belongs to the technical field of compressors, and in particular relates to a compressor.

Background Art

A fuel cell is a device that converts the chemical energy of hydrogen and oxygen into electrical energy through electrode reactions. The oxygen pressure in the fuel cell is directly related to the performance of the fuel cell system. Higher-pressure compressed air can increase the energy density of the fuel cell system and improve the efficiency of the battery stack. The core component of the fuel cell engine air supply system is the air compressor.

In order to obtain a better gas compression effect, a two-stage compressor has appeared in the prior art. The gas compressed in the first stage is passed into the second stage compression system for secondary compression. However, the two-stage compressor in the prior art has a complex structure and a large volume. Moreover, the impeller used for compressing the gas on this compressor is not easy to disassemble and assemble from the compressor, which makes it very difficult to replace, repair and convert the impeller of this compressor.

Summary of the invention

The present invention provides a compressor for solving the technical problems of the prior art that the two-stage compressor has a complex structure, a large volume and an impeller that is difficult to remove.

The present invention is implemented by the following technical solution: a compressor comprises an end cover and a shell having a first end and a second end, the first end is through, the second end is closed, and the end cover is sealed on the first end;

It also includes a double-shaft extension motor, a motor installation cavity is formed between the second end and the end cover, the double-shaft extension motor is installed in the motor installation cavity, one end of the rotating shaft of the double-shaft extension motor is rotatably plugged into the end cover and extends out of the end cover, and the other end of the rotating shaft of the double-shaft extension motor is rotatably plugged into the second end and extends out of the second end;

It also includes a first impeller, a first volute, a second impeller and a second volute, the first volute is detachably mounted on the end cover and a first compression chamber is formed between the first volute and the end cover, the first impeller is detachably mounted on a rotating shaft extending out of the end cover and is located in the first compression chamber, a first air inlet and a first air outlet are provided on the first volute, the second volute is detachably mounted on the second end and a second compression chamber is formed between the second volute and the second end, the second impeller is detachably mounted on a rotating shaft extending out of the second end and is located in the second compression chamber, a second air inlet and a second air outlet are provided on the second volute, and the first air outlet is connected to the second air inlet through an air pipe.

Further, in order to better implement the present invention, a spiral water groove surrounding the motor installation cavity is provided on the outer wall of the housing;

It also includes a shaft sleeve, the outer shell is inserted into the shaft sleeve and the outer wall of the outer shell is in contact with the inner wall of the shaft sleeve, the shaft sleeve is sleeved outside the spiral water trough, and the shaft sleeve is provided with a water inlet hole and a water outlet hole, and the water inlet hole and the water outlet hole are both connected to the spiral water trough.

Furthermore, in order to better implement the present invention, two sealing ring installation grooves for installing sealing rings are provided on the outer wall of the shell, the spiral water groove is located between the two sealing ring installation grooves, and the shaft sleeve is sleeved outside the two sealing ring installation grooves.

Furthermore, in order to better realize the present invention, two water leakage grooves are also provided on the outer shell, the two sealing ring mounting grooves and the spiral water groove are both located between the two water leakage grooves, the shaft sleeve is sleeved outside the two water leakage grooves and a water leakage hole is provided on the shaft sleeve, the number of the water leakage holes is also two, and the two water leakage holes are connected to the two water leakage grooves in a one-to-one correspondence.

Furthermore, in order to better implement the present invention, the shell is provided with a first hole connected to the motor installation cavity, the first hole is connected to the first air outlet through a pipeline, and the shell is also provided with a second hole for allowing the gas in the motor installation cavity to flow out.

Further, in order to better implement the present invention, the second hole includes an A hole provided on the side wall of the motor installation cavity, and the A hole and the first hole are respectively located at two ends of the motor installation cavity;

A first annular groove and a second annular groove are provided on the inner wall of the sleeve, the first annular groove and the second annular groove are respectively provided at two ends of the sleeve, and a straight hole is also provided inside the side wall of the sleeve, the straight hole communicates with the first annular groove and the second annular groove;

The first annular groove is connected to the A hole, and the groove wall of the second annular groove is provided with a B hole penetrating through the outer wall of the sleeve.

Furthermore, in order to better realize the present invention, a second bearing chamber is provided at the second end, in which a second radial air foil bearing and a thrust bearing for axially limiting the rotating shaft are installed, the rotating shaft is inserted into the second radial air foil bearing and the thrust bearing, and the thrust bearing and the end cover are respectively arranged on both sides of the second end.

Furthermore, in order to better realize the present invention, the second hole also includes a C hole that connects the second bearing chamber and the motor mounting cavity and a D hole for the gas in the second bearing chamber to flow out, the C hole is arranged on the second end, and the D hole is arranged on the side wall of the second bearing chamber.

Furthermore, in order to better implement the present invention, a first bearing chamber is provided on the end cover, a first radial air foil bearing is installed in the first bearing chamber, and the rotating shaft is inserted in the first radial air foil bearing.

Furthermore, in order to better implement the present invention, both the first bearing chamber and the second bearing chamber are installed with sealing sleeves for sealing, and the rotating shaft passes through the sealing sleeves.

Compared with the prior art, the present invention has the following beneficial effects:

The compressor provided by the present invention comprises an end cover, a casing and a double-shaft extension motor, the casing having a first end and a second end, the first end being through and the second end being closed, the end cover being sealed on the first end, the double-shaft extension motor being installed in the casing, one end of the double-shaft extension motor being rotatably plugged into the end cover and extending out of the end cover, and a first impeller being detachably installed on the extended section, the other end of the double-shaft extension motor being rotatably plugged into the second end and extending out of the second end, and a second impeller being detachably installed on the section extending out of the second end, and also comprising a first volute and a second volute, the first volute being detachably installed on the end cover and covering the first impeller, the second volute being detachably installed on the second end and covering the second impeller, the first volute being provided with a first air inlet and a first air outlet, the second volute being provided with a second air inlet and a second air outlet, and an air pipe being used to connect the first air outlet to the second air inlet The ports are connected, and the above structure is adopted. When the double-axle extension motor is powered on and running, the rotating shaft rotates, thereby driving the first impeller and the second impeller to rotate synchronously. The first impeller rotates in the first compression chamber between the above-mentioned end cover and the first volute, so that the gas entering from the first air inlet is compressed and then sent out from the first air outlet, and then reaches the second air inlet through the air pipe, and then is compressed twice by the second impeller rotating in the second compression chamber between the second end and the second volute, and finally is discharged from the second air outlet on the second volute. In this way, the gas pressure obtained by the compressor after compression is greater, and the structure of the entire compressor is simpler and more compact, and the first volute and the second volute are exposed outside the outer casing, which is convenient for disassembly and assembly. When the first volute and the second volute are removed, the first impeller and the second impeller can also be quickly disassembled and assembled, so as to be replaced and repaired in time.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic structural diagram of a compressor in an embodiment of the present invention;

FIG2 is an exploded view of the structure shown in FIG1 ;

FIG3 is another perspective view of the structure shown in FIG1 ;

FIG4 is an exploded view of the structure shown in FIG3 ;

FIG5 is another perspective view of the structure shown in FIG3;

Fig. 6 is a cross-sectional view of A-A in Fig. 5;

FIG7 is another perspective view of the structure shown in FIG5 (the first impeller and the second impeller are not shown);

Fig. 8 is a cross-sectional view B-B in Fig. 7;

FIG9 is a partial enlarged view of the C region in FIG8;

FIG10 is another perspective view of the structure shown in FIG5;

Fig. 11 is a cross-sectional view D-D in Fig. 10;

12 is a schematic structural diagram of a housing in an embodiment of the present invention;

FIG13 is another perspective view of the structure shown in FIG12;

FIG14 is another perspective view of the structure shown in FIG13;

15 is a schematic structural diagram of a sleeve in an embodiment of the present invention;

FIG16 is another perspective view of the structure shown in FIG15;

FIG. 17 is a diagram showing the structure shown in FIG. 16 from another perspective.

In the figure:

1-end cap;

2-housing; 21-first hole; 22-A hole; 23-C hole; 24-D hole;

3- Second end;

4-double shaft extension motor; 41-rotating shaft;

5- first impeller;

6-first volute; 61-first air inlet; 62-first air outlet;

7- second impeller;

8-second volute; 81-second air inlet; 82-second air outlet;

9-Spiral water tank;

10-shaft sleeve; 101-water inlet hole; 102-water outlet hole; 103-leakage hole; 104-first annular groove; 105-second annular groove; 106-straight hole; 107-B hole;

11- Sealing ring installation groove;

12- Leaky gutter;

13- second radial air foil bearing;

14-Thrust bearing;

15- first radial air foil bearing;

16-Sealing sleeve.

DETAILED DESCRIPTION

To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

Embodiment 1:

The present embodiment provides a compressor, including an end cover 1 and an outer shell 2, wherein the outer shell 2 is a cylindrical shell having a first end and a second end 3. It is worth noting that the first end and the second end 3 are the two ends of the cylindrical shell, wherein the first end is through and the second end 3 is closed, and the end cover 1 is sealed at the first end. It should be noted that the connection between the end cover 1 and the first end wall of the outer shell 2 is a detachable fixed connection, for example, the end cover 1 is installed on the first end wall using screws so that the end cover 1 can block the first end.

The compressor also includes a double-axle extension motor 4, which includes a stator and a rotating shaft 41, wherein the rotating shaft 41 is rotatably installed in the stator and both ends of the rotating shaft 41 extend out of the stator to form a double-axle extension structure. The cavity formed between the end cover 1 and the second end 3 is the motor installation cavity, one end of the rotating shaft 41 of the double-axle extension motor 4 is rotatably plugged into the end cover 1, and the rotating shaft 41 extends out of the end cover 1, and the other end of the rotating shaft 41 is rotatably plugged into the second end 3 and extends out of the second end 3, that is, both ends of the rotating shaft 41 of the double-axle extension motor 4 extend out of the end cover 1 and the second end 3 respectively, and the rotating shaft 41 can rotate freely.

The compressor also includes a first impeller 5 and a first volute 6. The first volute 6 is a shell, which is detachably mounted on the end cover 1 by screws and is located on a side away from the second end 3. A first compression chamber is formed between the first volute 6 and the end cover 1. The first impeller 5 is detachably mounted on a section of a rotating shaft 41 extending out of the end cover 1 and the first impeller 5 is located in the first compression chamber. It should be noted that the connection between the first impeller 5 and the rotating shaft 41 is keyed, and the center axis of the first impeller 5 is colinear with the center axis of the rotating shaft 41. In this way, when the double-axle extension motor 4 is powered on and operated, it will drive the first impeller 5 to rotate in the first compression chamber. A first air inlet 61 and a first air outlet 62 are provided on the first volute 6. During operation, air enters the first compression chamber from the first air inlet 61 and is compressed by the first impeller 5 and then discharged from the first air outlet 62. In the above structure, since the first volute 6 is located at one end of the outer shell 2, the first volute 6 can be quickly disassembled and assembled, and the first impeller 5 is also located outside the outer shell 2. When the first volute 6 is removed, the first impeller 5 can be quickly disassembled and assembled, so that the first impeller 5 can be replaced or repaired in time.

The compressor further comprises a second impeller 7 and a second volute 8, wherein the second volute 8 is a housing, which is detachably mounted on the second end 3 by screws and is located on a side away from the end cover 1, and a second compression chamber is formed between the second volute 8 and the second end 3, and the second impeller 7 is detachably mounted on a section of a rotating shaft 41 extending from the second end 3, and the second impeller 7 is located in the second compression chamber. It should be noted that the connection between the second impeller 7 and the rotating shaft 41 is keyed, and the center axis of the second impeller 7 is The second volute 8 is co-linear with the central axis of the rotating shaft 41. In this way, when the double-axle extension motor 4 is powered on and running, it will drive the second impeller 7 to rotate in the second compression chamber. The second volute 8 is provided with a second air inlet 81 and a second air outlet 82. The second air inlet 81 is connected with the first air outlet 62 through an air pipe. In this way, the compressed gas coming out of the first air outlet 62 will enter the second compression chamber and be further compressed by the second impeller 7, and finally be discharged from the second air outlet 82. In this way, the pressure of the gas discharged from the second air outlet 82 is higher. In the above structure, since the second volute 8 is located at the end of the outer shell 2, the second volute 8 can be quickly disassembled and assembled, and the second impeller 7 is also located outside the outer shell 2. When the second volute 8 is removed, the second impeller 7 can be quickly disassembled and assembled, so that the second impeller 7 can be replaced or repaired in time.

The compressor of this structure can realize two-stage compression of gas to output gas with higher pressure, and its structure is simple and compact, and it is convenient to quickly replace the first impeller 5 and the second impeller 7 as needed. It is highly practical, convenient for mass production of compressors, and reduces costs.

As a more preferred implementation of this embodiment, in this embodiment, a second bearing chamber is provided on the second end 3, and a second radial air foil bearing 13 and a thrust bearing 14 are installed in the second bearing chamber. The second radial air foil bearing 13 and the thrust bearing 14 are coaxially arranged, and the rotating shaft 41 of the double-axle extension motor 4 is plugged into the second radial air foil bearing 13 and the thrust bearing 14. The second radial air foil bearing 13 can radially bear the rotating shaft 41, and the second radial air foil bearing 13 will not directly contact the rotating shaft, thereby reducing wear. It is worth noting that the second radial air foil bearing 13 is actually a radial air foil bearing. Since the radial air foil bearing is a prior art, it will not be described in detail here. The thrust bearing 14 is used to realize axial positioning, limiting and bearing of the rotating shaft 4, and reduce the axial displacement of the rotating shaft 41.

In addition, a first bearing chamber is provided on the end cover 1, in which a first radial air foil bearing 15 is installed, and the rotating shaft 41 is also inserted in the first radial air foil bearing 15. It is worth noting that the first radial air foil bearing 15 is also an air foil bearing, so that the direct contact between the rotating shaft 41 and the end cover 1 can be avoided, so that the rotating shaft 41 can rotate more flexibly, and, by virtue of the characteristics of the air foil bearing, the rotating shaft 41 will not directly contact the first radial air foil bearing 15, thereby reducing the wear of the rotating shaft 41. Optimally, the first radial air foil bearing 15 and the second radial air foil bearing 13 are interchangeable.

With the above structure, in the compressor provided in this embodiment, the first radial air foil bearing 15, the thrust bearing 14 and the second radial air foil bearing 13 are all easy to replace, which facilitates the mass production of the compressor.

As a best implementation of this embodiment, in this embodiment, a sealing sleeve 16 for sealing is installed in the first bearing chamber and the second bearing chamber. Specifically, the sealing sleeve 16 is installed at the end away from the double-axle extension motor 4 and the sealing sleeve 16 at the second end 3 is flush with the housing 2, and the sealing sleeve 16 at the end cover 1 is flush with the end cover 1, so as to further enhance the compactness of the structure. The sealing sleeve 16 can prevent gas leakage from the first bearing chamber on the end cover 1 and the second bearing chamber at the second end 3.

Embodiment 2:

This embodiment is a better implementation of embodiment 1. In the compressor provided by this embodiment, a spiral water groove 9 surrounding the motor installation cavity is further provided on the outer wall of the above-mentioned shell 2. Cooling liquid such as cooling water or coolant can be passed into the spiral water groove 9, so as to cool the cavity wall of the motor installation cavity and realize the function of cooling the dual-axis extension motor 4.

The compressor provided in this embodiment also includes a sleeve 10, and the above-mentioned shell 2 is inserted into the sleeve 10, and the outer wall of the sleeve 10 is in contact with the inner wall of the above-mentioned shell 2, and the sleeve 10 is sleeved outside the above-mentioned spiral water groove 9, so that the inner wall of the sleeve 10 and the spiral water groove 9 form a spiral flow channel to facilitate the circulation of cooling liquid. The above-mentioned sleeve 10 is also provided with a water inlet hole 101 and a water outlet hole 102, and the water inlet hole 101 and the water outlet hole 102 are both connected to the above-mentioned spiral water groove 9. When in use, the cooling liquid is injected from the water inlet hole 101, and the cooling liquid enters the spiral water groove 9 and flows therein, and then enters the water outlet hole 102, and is discharged from the water outlet hole 102, so that the water in the spiral water groove 9 is flowing water, so as to further improve the cooling effect. Optimally, the above-mentioned water inlet hole 101 is set at the spiral starting end of the spiral water groove 9, and the above-mentioned water outlet hole 102 is set at the spiral ending end of the spiral water groove 9.

As a more preferred implementation of this embodiment, in this embodiment, two sealing ring installation grooves 11 are provided on the outer wall of the housing 2, and the sealing ring installation grooves 11 are used to install sealing rings (not shown in the figure), and the spiral water trough 9 is located between the two sealing ring installation grooves 11. Moreover, the shaft sleeve 10 is also sleeved outside the two sealing ring installation grooves 11, and when the sealing rings are installed in the sealing ring installation grooves 11, the shaft sleeve 10 presses the sealing rings. With this structure, sealing rings are provided at both ends of the spiral water trough 9, so that the cooling liquid overflowing the spiral water trough 9 can be prevented from leaking out from both sides of the spiral water trough 9.

As a best implementation of this embodiment, in this embodiment, two water leakage grooves 12 are further provided on the housing 2, and the water leakage grooves 12 are annular grooves coaxial with the housing 2. The two sealing ring installation grooves 11 and the spiral water groove 9 are both located between the two water leakage grooves 12. When the sealing ring is damaged, the cooling liquid will flow into the water leakage grooves 12. The shaft sleeve 10 is also sleeved outside the two water leakage grooves 12, and two water leakage holes 103 are provided on the shaft sleeve 10. The two water leakage holes 103 are connected to the two water leakage grooves 12 in a one-to-one correspondence. In this way, the cooling liquid entering the water leakage grooves 12 can be discharged through the water leakage holes 103, thereby further preventing the cooling liquid from flowing out of the gap between the shaft sleeve 10 and the housing 2, and further achieving a leak-proof effect.

Embodiment 3:

This embodiment is a better implementation of the above embodiment. In this embodiment, a first hole 21 connected to the motor mounting cavity is further provided on the above-mentioned shell 2. The first hole 21 is connected to the above-mentioned first air outlet 62 through a pipeline. Part of the gas coming out of the first air outlet 62 will enter the above-mentioned first hole 21 through the pipeline, and finally enter the above-mentioned motor mounting cavity, so as to air-cool the dual-axle extension motor 4 in the motor mounting cavity, thereby further improving the cooling effect of the dual-axle extension motor 4.

In this embodiment, a second hole is further provided on the housing 2, the second hole is also connected to the motor installation cavity and is used to discharge the gas in the motor installation cavity to avoid excessive gas pressure in the motor installation cavity.

Embodiment 4:

This embodiment is a specific implementation of embodiment 3. In the compressor provided by this embodiment, the above-mentioned second hole includes an A hole 22, and the A hole 22 is arranged on the side wall of the motor mounting cavity, and the A hole 22 and the above-mentioned first hole 21 are respectively arranged at the two ends of the motor mounting cavity, so that the A hole 22 and the first hole 21 are respectively located at the two ends of the stator of the double-axis extension motor 4. In this way, the gas entering from the first hole 21 will pass through the inside of the double-axis extension motor 4 to cool the inside of the double-axis extension motor 4, and then reach the A hole 22, and be discharged from the motor mounting cavity through the A hole 22. In this way, the cooling effect on the double-axis extension motor 4 can be further enhanced.

The above-mentioned sleeve 10 is sleeved outside the above-mentioned A hole 22, and a first annular groove 104 and a second annular groove 105 are respectively provided at both ends of the sleeve 10, and a straight hole 106 is also provided inside the side wall of the sleeve 10. The above-mentioned first annular groove 104 and the second annular groove 105 are connected through the straight hole 106. It is worth noting that the straight hole 106 spans the above-mentioned spiral water groove 9, and the above-mentioned first annular groove 104 is located on the side close to the A hole 22 and is directly connected to the above-mentioned A hole 22. The airflow coming out of the A hole 22 will enter the above-mentioned first annular groove 104, and then enter the above-mentioned straight hole 106, and then enter the above-mentioned second annular groove 105. The second annular groove 106 is located on the side close to the above-mentioned first hole 21. In this process, the gas flowing in the straight hole 106 will cool the sleeve 10, thereby cooling the cooling liquid flowing in the above-mentioned spiral water groove 9, so that the cooling effect of the double-axle extension motor 4 is better. A B hole 107 penetrating the outer wall of the sleeve 10 is provided on the groove wall of the second annular groove 105, so that the gas entering the second annular groove 105 will be discharged to the outside of the compressor from the B hole 107. Specifically, the first hole 21 is provided on the outer shell 2 near the second end 3, the B hole 107 is provided on the sleeve 10 near the second end 3, and the A hole 22 is provided on the outer shell 2 near the end cover 3. Optimally, the number of the A holes 22 is six, and the six A holes 22 are distributed on the outer shell 2 in a circular array with the central axis of the outer shell as the center, and the number of the straight holes 106 is also six, and the six straight holes 106 are distributed in the side wall of the sleeve 10 in a circular array with the central axis of the sleeve 10 as the center, so as to achieve a better flow guiding effect.

As a more preferred implementation of this embodiment, in this embodiment, the second hole further includes a C hole 23 and a D hole 24, the second bearing chamber and the motor installation chamber are respectively located on both sides of the second end 3, the C hole 23 is arranged on the second end 3, and the C hole 23 conducts the motor installation chamber and the second bearing chamber, so that part of the gas entering the motor installation chamber from the first hole 21 will flow into the second bearing chamber through the C hole 21 to cool the thrust bearing 14 and the second radial air foil bearing 13 in the second bearing chamber, so as to improve the stability of the compressor in this embodiment. The D hole 24 is arranged on the side wall of the second bearing chamber to guide the gas in the second bearing chamber to the surrounding environment, thereby avoiding excessive gas pressure in the second bearing chamber. Optimally, the number of the C holes 23 is 12, and the 12 C holes 23 are distributed on the second end 3 in a circular array with the central axis of the housing 2 as the center, so as to achieve a better flow diversion effect.

The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (7)

1. A compressor, characterized in that it comprises an end cover and a housing having a first end and a second end, wherein the first end is through-connected and the second end is closed, and the end cover is sealed on the first end; It also includes a double-shaft extension motor, a motor installation cavity is formed between the second end and the end cover, the double-shaft extension motor is installed in the motor installation cavity, one end of the rotating shaft of the double-shaft extension motor is rotatably plugged into the end cover and extends out of the end cover, and the other end of the rotating shaft of the double-shaft extension motor is rotatably plugged into the second end and extends out of the second end; The invention also comprises a first impeller, a first volute, a second impeller and a second volute, wherein the first volute is detachably mounted on the end cover and a first compression chamber is formed between the first volute and the end cover, the first impeller is detachably mounted on a rotating shaft extending from the end cover and is located in the first compression chamber, a first air inlet and a first air outlet are provided on the first volute, the second volute is detachably mounted on the second end and a second compression chamber is formed between the second volute and the second end, the second impeller is detachably mounted on a rotating shaft extending from the second end and is located in the second compression chamber, a second air inlet and a second air outlet are provided on the second volute, and the first air outlet is communicated with the second air inlet through an air pipe; The outer wall of the housing is provided with a spiral water groove surrounding the motor installation cavity; It also includes a shaft sleeve, the outer shell is inserted into the shaft sleeve, and the outer wall of the outer shell is in contact with the inner wall of the shaft sleeve, the shaft sleeve is sleeved outside the spiral water trough, and the shaft sleeve is provided with a water inlet hole and a water outlet hole, and the water inlet hole and the water outlet hole are both connected to the spiral water trough; The housing is provided with a first hole communicating with the motor installation cavity, the first hole is communicated with the first gas outlet through a pipeline, and the housing is also provided with a second hole for allowing gas in the motor installation cavity to flow out; The second hole comprises an A hole provided on the side wall of the motor installation cavity, and the A hole and the first hole are respectively located at two ends of the motor installation cavity; A first annular groove and a second annular groove are provided on the inner wall of the sleeve, the first annular groove and the second annular groove are respectively provided at two ends of the sleeve, and a straight hole is also provided inside the side wall of the sleeve, the straight hole communicates with the first annular groove and the second annular groove; The first annular groove is connected to the A hole, and the groove wall of the second annular groove is provided with a B hole penetrating through the outer wall of the sleeve. 2. A compressor according to claim 1, characterized in that: two sealing ring installation grooves for installing the sealing ring are provided on the outer wall of the shell, the spiral water groove is located between the two sealing ring installation grooves, and the shaft sleeve is sleeved outside the two sealing ring installation grooves. 3. A compressor according to claim 2, characterized in that: two water leakage grooves are also provided on the outer shell, the two sealing ring mounting grooves and the spiral water groove are both located between the two water leakage grooves, the shaft sleeve is sleeved outside the two water leakage grooves and a water leakage hole is provided on the shaft sleeve, the number of the water leakage holes is also two, and the two water leakage holes are connected to the two water leakage grooves in a one-to-one correspondence. 4. A compressor according to claim 1, characterized in that: a second bearing chamber is provided at the second end, a second radial air foil bearing and a thrust bearing for axially limiting the rotating shaft are installed in the second bearing chamber, the rotating shaft is inserted into the second radial air foil bearing and the thrust bearing, and the thrust bearing and the end cover are respectively arranged on both sides of the second end. 5. A compressor according to claim 4, characterized in that: the second hole also includes a C hole connecting the second bearing chamber and the motor mounting chamber and a D hole for the gas in the second bearing chamber to flow out, the C hole is arranged on the second end, and the D hole is arranged on the side wall of the second bearing chamber. 6. A compressor according to claim 4, characterized in that: a first bearing chamber is provided on the end cover, a first radial air foil bearing is installed in the first bearing chamber, and the rotating shaft is inserted in the first radial air foil bearing. 7. A compressor according to claim 6, characterized in that: the first bearing chamber and the second bearing chamber are both equipped with sealing sleeves for sealing, and the rotating shaft passes through the sealing sleeves.