CN117989177A

CN117989177A - Cooling structure of air compressor and air compressor

Info

Publication number: CN117989177A
Application number: CN202410405472.9A
Authority: CN
Inventors: 贾金信; 蔡由俊; 薛家宁; 苏久展; 廖繁林
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2024-04-07
Filing date: 2024-04-07
Publication date: 2024-05-07

Abstract

The invention provides an air compressor cooling structure and an air compressor, wherein the air compressor cooling structure comprises a shell, a rotor and a stator are arranged in the shell, one end of the rotor is provided with a first compression assembly, an exhaust port of the first compression assembly is communicated with the interior of the shell so that compressed gas enters the shell, a cooling assembly is arranged on the shell, and the gas entering the shell flows between the rotor and the stator after exchanging heat with the cooling assembly and is discharged from the shell. According to the invention, the defect that the reliability of the air compressor is low because the motor stator, the motor rotor and the matched air dynamic pressure bearing of the air compressor cannot be sufficiently cooled in the prior art can be overcome.

Description

Cooling structure of air compressor and air compressor

Technical Field

The invention belongs to the technical field of air compressors, and particularly relates to an air compressor cooling structure and an air compressor.

Background

At present, a centrifugal air compressor using a gas bearing as a rotor support is designed to do work in a direct-drive mode of a high-speed motor, a motor rotor and a main shaft are made into an integrated structure, a centrifugal impeller is mounted at the shaft end of the main shaft, and the impeller is arranged in a volute outside the motor. The air in the spiral case is continuously compressed by the ultra-high-speed rotation of the motor rotor, and the compressed air with high pressure and high temperature is supplied to the fuel cell engine to participate in the electrochemical reaction in the fuel cell stack, wherein the air floating pressure bearing provides necessary support for the rotor (comprising impeller-thrust disc-main shaft-impeller) for the high-speed rotation of the integrated rotating component.

In order to ensure the pressure and flow of output air, the air suspension centrifugal air compressor needs to operate in an ultra-high speed region (more than 80000 Rpm) for a long time, and an ultra-high speed rotor also brings about the heat dissipation and cooling problems of the whole machine and the air bearing.

Therefore, when the air compressor works for a long time, a large amount of heat can be generated by the electrifying operation of the motor stator and the high-speed rotation of the rotor, the heat accumulated in the air compressor can influence the motor stator and the control circuit thereof as well as the running states of the rotor and the motor gas bearing, and heat dissipation is needed to be effectively realized in time.

From the above, the power density of the bipolar centrifugal air compressor with high power and high current leads to higher heat dissipation requirement of the motor body on the whole machine. In the long-term high-speed operation process of the air suspension high-speed motor, the stator, the rotor and the matched air dynamic pressure bearing of the motor tend to be easy to generate heat accumulation phenomena, so that the air dynamic pressure bearing is heated and damaged, the rotating shaft is thermally elongated and seriously fails, the whole machine is in failure, a cooling system of the centrifugal air compressor in the prior art is a motor shell for water cooling, a cooling water channel is arranged on the shell for cooling the inside of the shell, and the stator, the rotor and the matched air dynamic pressure shaft of the motor are sequentially sleeved in the shell.

Because the motor stator, the rotor and the matched air dynamic pressure bearing of the air compressor in the prior art cannot be sufficiently cooled, the air bearing is damaged by heating, the rotating shaft is thermally elongated, the reliability of the air compressor is low and the like, the invention designs the cooling structure of the air compressor and the air compressor.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the defect that the reliability of the air compressor is low because the motor stator, the motor rotor and the matched air dynamic pressure bearing of the air compressor cannot be sufficiently cooled in the prior art, so as to provide the cooling structure of the air compressor and the air compressor.

In order to solve the problems, the invention provides a cooling structure of an air compressor, which comprises a shell, wherein a rotor and a stator are arranged in the shell, one end of the rotor is provided with a first compression assembly, an exhaust port of the first compression assembly is communicated with the inside of the shell so that compressed gas enters the shell, a cooling assembly is arranged on the shell, and the gas entering the shell flows between the rotor and the stator after exchanging heat with the cooling assembly and is discharged from the shell.

In some embodiments, the other end of the rotor is provided with a second compression assembly, the housing is provided with an air inlet, the air inlet is located on the housing and is close to the first compression assembly relative to the second compression assembly, along the circumference of the housing, the housing is provided with a cooling channel, the cooling channel is communicated with the air inlet, along the axial direction of the housing, the housing is provided with a plurality of first diversion holes, along the circumference of the housing, one end of the first diversion holes is communicated with the cooling channel, and the other end of the first diversion holes is communicated with the interior of the housing.

In some embodiments, the other end of the first diversion hole is located on the housing and is close to the second compression assembly relative to the first compression assembly, and after the air flow flowing in the first diversion hole enters between the rotor and the stator, the air flow flows along the second compression assembly towards the first compression assembly. In some embodiments, the exhaust port of the first compression assembly is communicated with the air suction port of the second compression assembly through a first connecting pipe, and the first connecting pipe is communicated with the air inlet through a second connecting pipe, so that the air discharged by the first compression assembly at least partially flows into the shell.

In some embodiments, the housing has a first end and a second end, the first end is provided with a first cover, the first compression assembly is disposed on the first cover, a groove is disposed on the first cover, a first thrust bearing and a second thrust bearing are disposed on two side walls of the groove respectively, a thrust disc is disposed on the rotor, the thrust disc is at least partially disposed in the groove, and the thrust disc is disposed between the first thrust bearing and the second thrust bearing, and an air flow flowing through the rotor can flow into the groove. In some embodiments, a plurality of second diversion holes are uniformly arranged along the circumferential direction of the rotor and are arranged on the first cover body along the axial direction of the rotor, one end of each second diversion hole is communicated with the corresponding groove, the other end of each second diversion hole is communicated with the inside of the shell, an air outlet is formed in the first cover body, and air flowing into the corresponding groove is discharged out of the shell through the corresponding air outlet.

In some embodiments, the rotor includes a first shaft, a shaft sleeve, an intermediate section and a second shaft, the intermediate section is located between the first shaft and the second shaft, the intermediate section, the first shaft at least partially, and the second shaft at least partially are sleeved in the shaft sleeve, along the axial direction of the second shaft, a plurality of guide grooves are arranged on the second shaft along the circumferential direction of the second shaft, and when the rotor rotates, the guide grooves can drive airflow in the shell to flow along the second shaft towards the direction of the first shaft.

In some embodiments, the first shaft is located within the housing proximate the first compression assembly, the outer wall of the second shaft has an inclined section that is inclined along the shaft sleeve toward a centerline of the second shaft, and the flow guide groove is located at the inclined section.

In some embodiments, the cooling assembly includes a cooling flow channel, the cooling flow channel is spirally disposed on the housing, and two ends of the cooling flow channel are communicated with the outside of the housing.

The invention also provides an air compressor, which comprises the air compressor cooling structure.

The cooling structure of the air compressor and the air compressor provided by the invention have the following beneficial effects:

The exhaust port of the first compression assembly is communicated with the inside of the shell, so that the gas exhausted by the first compression assembly can enter the shell to cool all components in the shell, a cooling assembly is arranged on the shell and is used for cooling the shell, after the gas flows into the shell, the gas is subjected to heat exchange through the shell and the cooling assembly, so that the gas exhausted by the first compression assembly is subjected to sufficient heat exchange and cooling, then flows between the rotor and the stator to cool the rotor and the stator, the high-speed motor stator and the high-speed motor rotor which have the most serious influence on the operation and the heat generation of the high-speed motor are sufficiently cooled, the heat accumulation in the compression mechanism with high energy density and high power is avoided, and the abnormal temperature rise of the high-speed motor stator is avoided, and the electromagnetic safety is influenced; the problem that the clearance between the impeller and the volute is affected due to the fact that a high-speed motor shaft is elongated due to high temperature is avoided, and the reliability of the air compressor is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It will be apparent to those skilled in the art from this disclosure that the drawings described below are merely exemplary and that other embodiments may be derived from the drawings provided without undue effort.

The structures, proportions, sizes, etc. shown in the present specification are shown only for the purposes of illustration and description, and are not intended to limit the scope of the invention, which is defined by the claims, so that any structural modifications, changes in proportions, or adjustments of sizes, which do not affect the efficacy or the achievement of the present invention, should fall within the ambit of the technical disclosure.

Fig. 1 is a schematic diagram of a cooling structure of an air compressor according to an embodiment of the present invention;

Fig. 2 is a schematic diagram of a gas flow direction of a cooling structure of an air compressor according to an embodiment of the present invention;

FIG. 3 is an enlarged view of a portion of FIG. 2 at A;

FIG. 4 is a schematic diagram illustrating stress analysis of a rotor in operation in a cooling structure of an air compressor according to an embodiment of the present invention;

fig. 5 is an assembly view of a rotor in a cooling structure of an air compressor according to an embodiment of the present invention;

Fig. 6 is a schematic structural diagram of a rotor in a cooling structure of an air compressor according to an embodiment of the present invention;

fig. 7 is a cross-sectional view of a rotor in a cooling structure of an air compressor according to an embodiment of the present invention;

Fig. 8 is a schematic diagram illustrating a gas flow direction of a casing in the cooling structure of the air compressor according to the embodiment of the invention;

Fig. 9 is a side view of a housing in a cooling structure of an air compressor according to an embodiment of the present invention;

Fig. 10 is a schematic structural diagram of a first cover in the cooling structure of the air compressor according to the embodiment of the invention;

fig. 11 is a top view of a first cover in a cooling structure of an air compressor according to an embodiment of the invention.

The reference numerals are expressed as:

1. a first volute; 2. a first impeller; 3. a first diffuser; 4. a first thrust bearing; 5. a thrust plate; 6. a second thrust bearing; 7. a first cover; 8. a first air bearing; 9. a rotor; 10. a stator; 11. a housing; 12. a diversion trench; 13. a second air bearing; 14. A second cover; 15. a second impeller; 16. a second volute; 17. a first connection pipe; 18. a second connection pipe; 19. a first shaft; 20. a shaft sleeve; 21. an intermediate section; 22. a second shaft; 23. an air outlet; 24. A cooling channel; 25. an air inlet; 26. a first deflector aperture; 27. and a second deflector hole.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

It should be understood that the term "and/or" as used herein is merely one relationship describing the association of the associated objects, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

In the description of the present invention, it should be understood that the azimuth or positional relationships indicated by the azimuth terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal", and "top, bottom", etc., are generally based on the azimuth or positional relationships shown in the drawings, merely to facilitate description of the present invention and simplify the description, and these azimuth terms do not indicate and imply that the apparatus or elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the scope of protection of the present invention; the orientation word "inner and outer" refers to inner and outer relative to the contour of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "upper surface on … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial location relative to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the exemplary term "above … …" may include both orientations "above … …" and "below … …". The device may also be positioned in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In addition, the terms "first", "second", etc. are used to define the components, and are only for convenience of distinguishing the corresponding components, and the terms have no special meaning unless otherwise stated, and therefore should not be construed as limiting the scope of the present invention.

Referring to fig. 1 to 11 in combination, according to an embodiment of the present invention, there is provided a cooling structure of an air compressor, including a housing 11, wherein a rotor 9 and a stator 10 are disposed in the housing 11, a first compression assembly is disposed at one end of the rotor 9, an exhaust port of the first compression assembly is communicated with the interior of the housing 11, so that compressed air enters the housing 11, a cooling assembly is disposed on the housing 11, and the air entering the housing 11 exchanges heat with the cooling assembly, flows between the rotor 9 and the stator 10, and is discharged from the housing 11. According to the technical scheme, the exhaust port of the first compression assembly is communicated with the inside of the shell 11, so that gas exhausted by the first compression assembly can enter the shell 11 to cool all components in the shell 11, a cooling assembly is arranged on the shell 11 and is used for cooling the shell 11, after the gas flows into the shell 11, the gas firstly exchanges heat with the cooling assembly through the shell 11, so that the gas exhausted by the first compression assembly is fully exchanged for cooling and then flows between the rotor 9 and the stator 10 to cool the rotor 9 and the stator 10, and the high-speed motor stator and the high-speed motor rotor which have the most serious influence on the operation and heating of the high-speed motor are fully cooled to avoid heat accumulation in the high-energy density and high-power compression mechanism, so that abnormal temperature rise of the high-speed motor stator is avoided and electromagnetic safety is influenced; the problem that the clearance between the impeller and the volute is affected due to the fact that a high-speed motor shaft is elongated due to high temperature is avoided, and the reliability of the air compressor is improved.

In the related art, a cooling structure of an air compressor is provided, and a two-stage air suspension centrifugal compressor consists of a first-stage compression volute, a first-stage compression impeller, a first-stage diffuser, a front axial thrust bearing, a high-speed motor thrust disc, a rear axial thrust bearing, a first-stage end cover, a front axial air bearing, a high-speed motor rotor, a high-speed motor stator, a water-cooling shell, a rear radial air bearing, a second-stage end cover, a second-stage compression impeller, a second-stage compression volute and a connecting pipe. When the two-stage air compressor runs at a high speed, the axial dynamic pressure bearing, the front radial bearing and the rear radial bearing which support the movement and limit of the motor rotor can generate a large amount of heat due to wind mill resistance; meanwhile, the stator core and the high-speed rotor of the high-speed motor also generate eddy current loss and iron loss due to electromagnetic induction effect; in addition, the copper loss of the stator winding generates a large amount of heat due to the presence of a large current. However, due to the limitation of the structure of the dual-stage air compressor, a general cooling strategy of the dual-stage air compressor is generally divided into two parts: one part of the process is to open up a cooling water channel on the shell so that heat generated by the high-speed motor stator is transferred along the contact surface of the motor stator and the shell in a water-cooling way, and under the condition, the motor stator is further encapsulated, so that the contact surface of the shell and the motor stator can be increased, and the heat exchange efficiency of the motor winding and the shell is improved. However, a single water cooling scheme has limitations, firstly, the cooling effect is poor, no matter how the water channel is arranged, the cooling range of the motor stator is limited, and no matter whether glue is filled or not, the motor winding far away from the cooling water channel is difficult to comprehensively dissipate heat; secondly, the temperature of cooling water is 50-70 ℃, at the water temperature, the cooling effect of a water channel cannot be comprehensively acted on the heating position of the motor, and the taken heat is limited and the efficiency is low; most importantly, the setting of water cooling way can't cool off high-speed motor rotor completely, and under high temperature operation, high-speed motor stator outwards radiates heat, constantly heats the rotor for the rotor is heated the extension, leads to second grade side impeller to the rear ejecting, contacts with the second grade spiral case, takes place to scratch, influences the air compressor machine performance, directly leads to the air compressor machine inefficacy. Besides cooling water, an air cooling channel can be arranged in the air compressor to cool the air bearing, the thrust disc and the high-speed motor rotor. The composition of which can be referred to the partially enlarged air-cooled flow schematic of fig. 1: bearing cooling gas for the primary compression end often adopts compressed gas leaked by the primary compression impeller, passes through the back surface of the primary compression impeller, passes through the gap of the primary diffuser, enters an annular axial bearing chamber formed by an axial dynamic pressure bearing, a thrust disc and a primary end cover, and passes through the primary end cover after cooling the axial dynamic pressure bearing and the thrust disc, flows into a motor cavity through the back surface of a front radial bearing, and simultaneously cools a stator core and a rotor of the high-speed motor. The air cooling scheme has the advantages of small flow, high cooling air temperature, difficulty in suppressing heat accumulation in the bearing and the motor and poor cooling effect.

In order to solve the problems that the heat dissipation of a stator and a rotor of a high-speed motor is difficult and the axial force is overlarge when the rotor of the high-speed motor runs in an operating state of the ultra-high-speed motor, the cooling structure of the air compressor is provided with the internal diversion grooves by adjusting the structure of the whole machine, so that air compressor diversion cooling gas flows along the internal flow channel of a shell, the temperature of the cooling gas is reduced under the action of cooling water, the heat of the stator and the rotor of the motor is taken away along a set flow direction in the operating process of the motor, the temperature rise stability of the motor is ensured, the self-cooling of the stator and a pneumatic bearing is realized, and meanwhile, the diversion fan can provide a certain axial force to offset the axial pressure of a compression impeller, the working pressure of the air bearing is reduced, and the reliability of the whole machine is improved.

In some embodiments, a second compression assembly is disposed at the other end of the rotor 9, an air inlet 25 is disposed on the housing 11, the air inlet 25 is located on the housing 11 and near the first compression assembly relative to the second compression assembly, a cooling channel 24 is disposed on the housing 11 along the circumferential direction of the housing 11, the cooling channel 24 is communicated with the air inlet 25, the first diversion holes 26 are disposed on the housing 11 along the axial direction of the housing 11, a plurality of first diversion holes are uniformly disposed along the circumferential direction of the housing 11, one end of each first diversion hole 26 is communicated with the cooling channel 24, and the other end is communicated with the interior of the housing 11. In this technical scheme, along the circumference of casing 11, be provided with cooling channel 24 on the casing 11, cooling channel 24 is the annular channel, through cooling channel 24, evenly divide into each first water conservancy diversion hole 26 with the air current that air inlet 25 flowed in for get into the inside of casing 11 gas and cooling module and obtain abundant heat transfer, flow into the inside of casing 11 after the heat transfer, cool off rotor and stator, avoid regional cooling inhomogeneous, improve cooling effect.

According to the cooling structure of the air compressor, two stages of compression impellers are arranged on two sides of a complete machine on an air suspension high-speed motor with a compression impeller structure, an air flow channel is arranged on the two sides of the complete machine, the air flow channel firstly passes through a motor shell, and after stable flow division of the motor shell, the air flow channel is arranged inside the air suspension high-speed motor, and under the rotation of a built-in guide fan or a guide groove on a high-speed motor shaft, sucked cooling air can fully exchange heat with cooling water, and the air suspension high-speed motor becomes directional flow air with lower temperature when reaching a motor cavity, so that the stator, the rotor and an air bearing which are difficult to dissipate heat inside the high-speed motor are effectively cooled, the internal heat exchange condition of the high-speed motor is improved, various problems caused by internal heat accumulation are avoided, meanwhile, the air pressure inside the motor cavity is increased, the performance of the dynamic pressure air bearing is improved, and the reliability and the service life of the complete machine of the air compressor are further improved. Meanwhile, the diversion trenches are arranged on the rotor of the high-speed motor, so that a part of smaller axial force can be provided, the axial force from the whole machine to the primary compression side is reduced in the rotating process of the rotor, namely, the bearing capacity required by the air bearing of the whole machine is reduced, the bearing threshold is improved by phase change, and the guarantee is provided for the stable operation of the rotor under high load.

After entering the shell 11, the cooling gas enters the annular cooling channel 24 of the first cover body, so that the speed of the cooling gas entering the motor shell is reduced, and the cooling gas can be ensured to exchange heat with the cooling flow channel sufficiently; six groups/eight groups of first diversion holes 26 are arranged in the annular cooling channel 24 and are directly arranged on the shell 11, one end of the first diversion holes is connected with the cooling channel 24, the other end of the first diversion holes is connected with a rear motor cavity of the motor, cooling gas flows in the cooling channel 24 after entering the annular cooling channel 24, the cooling gas flow obtained by the air guide channels of each group of the shell can be ensured to be basically consistent, the cooling effect of the cooling gas flow is kept consistent, and uneven regional cooling is avoided.

In some embodiments, the other end of the first diversion hole 26 is located on the housing 11 and is close to the second compression assembly relative to the first compression assembly, and after the air flow flowing into the first diversion hole 26 enters between the rotor 9 and the stator 10, the air flow flows along the second compression assembly towards the first compression assembly. In this technical scheme, after the air current that flows in through first water conservancy diversion hole 26 gets into between rotor 9 with stator 10, along second compression subassembly orientation first compression subassembly's direction flows for after the air current gets into casing 11, at first along first compression subassembly orientation second compression subassembly's direction flows, carries out abundant heat transfer with cooling module, then follows second compression subassembly orientation first compression subassembly's direction flows, cools off rotor and stator, makes the abundant heat transfer of gas in casing 11, improves the cooling effect.

In some embodiments, the exhaust port of the first compression assembly is communicated with the air suction port of the second compression assembly through a first connecting pipe 17, and the first connecting pipe 17 is communicated with the air inlet 25 through a second connecting pipe 18, so that the air discharged by the first compression assembly flows into the shell 11 at least partially.

The cooling structure of the air compressor changes the flowing mode and path of cooling air, adjusts the whole structure, can induce air to flow through the motor shell first, flows to the high-speed motor stator and the high-speed motor rotor with serious heat generation under the sufficient cooling of cooling liquid, effectively cools the motor rotor and the motor stator, and exchanges heat with the motor stator and the motor rotor in real time in the running process of the high-speed motor by a large amount of imported normal-temperature air, thereby avoiding the heat accumulation of the cooling air, avoiding the heat bending effect and the shaft extension of the rotor under the high-temperature condition, avoiding the contact of the rotor with an air bearing and the influence on the set gap between the impeller and the volute under the shaft extension, further ensuring the compression performance not to be influenced by temperature, prolonging the service life of the rotor and improving the heat environment of the whole compressor. When cooling the motor cavity, the sucked air can also dissipate heat and supplement air to the air bearing, and the effect is beneficial to improving the use reliability of the air bearing, so that the reliability of the whole air compressor is improved.

In some embodiments, the housing 11 has a first end and a second end, the first end is provided with a first cover 7, the first compression component is disposed on the first cover 7, a groove is disposed on the first cover 7, two side walls of the groove are respectively provided with a first thrust bearing 4 and a second thrust bearing 6, a thrust disc 5 is disposed on the rotor 9, the thrust disc 5 is at least partially disposed in the groove, and the thrust disc 5 is disposed between the first thrust bearing 4 and the second thrust bearing 6, and an air flow flowing through the rotor 9 can flow into the groove. In this technical scheme, the recess is the annular groove, and its opening is towards rotor 9, and thrust disk 5 is at least partially located in the recess, just, thrust disk 5 is located first thrust bearing 4 with between the second thrust bearing 6, after the cooling gas that flows through rotor 9 and stator 10 gets into the recess, to thrust disk 5 first thrust bearing 4 with second thrust bearing 6 cools off, can also carry out the air supplement to first thrust bearing 4 with second thrust bearing 6, first air bearing 8, second air bearing 13, be favorable to improving air bearing's reliability of use, and then improve the reliability of air compressor machine complete machine.

In some embodiments, the first cover 7 is provided with second diversion holes 27 along the axial direction of the rotor 9, a plurality of second diversion holes 27 are uniformly arranged along the circumferential direction of the rotor 9, one end of each second diversion hole 27 is communicated with the groove, the other end of each second diversion hole is communicated with the inside of the shell 11, the first cover 7 is provided with an air outlet 23, and air flowing into the groove is discharged out of the shell 11 through the air outlet 23. In this technical scheme, through the second water conservancy diversion hole 27 for after the cooling gas that flows through rotor 9 and stator 10 gets into the recess, to thrust disk 5 first footstep bearing 4 with second footstep bearing 6 cools off, can also mend gas to first footstep bearing 4 with second footstep bearing 6, finally discharges into the atmosphere through gas outlet 23, certainly, also can be with gas outlet 23 and first compression assembly's induction port intercommunication, make the gas after the cooling reenter in the first compression assembly compress, make the air current obtain reuse.

In some embodiments, the rotor 9 includes a first shaft 19, a shaft sleeve 20, an intermediate section 21, and a second shaft 22, where the intermediate section 21 is located between the first shaft 19 and the second shaft 22, the intermediate section 21, the first shaft 19, and the second shaft 22 are at least partially sleeved in the shaft sleeve 20, and a plurality of flow guide grooves 12 are disposed on the second shaft 22 along the axial direction of the second shaft 22, and along the circumferential direction of the second shaft 22, the flow guide grooves 12 are disposed in a plurality of positions, and when the rotor 9 rotates, the flow guide grooves 12 can drive the airflow in the housing 11 to flow along the second shaft 22 toward the first shaft 19. In the technical scheme, through the diversion trench 12, airflow directionally flows in the shell 11, and in the running process of the high-speed motor, cooling gas exchanges heat with the motor stator and the motor rotor in real time, so that internal heat accumulation is avoided, the heat bending effect and shaft extension of the rotor under the high-temperature condition are avoided, the contact of the rotor and an air bearing and the set gap between the impeller and the volute are avoided, the compression performance is not influenced by temperature, the service life of the rotor is prolonged, and the thermal environment of the whole machine is improved.

Referring to fig. 4, under the drive of the high-speed motor rotor 9, the axial force F1 generated by the first impeller 2 is leftward, the axial force F2 generated by the second impeller 15 is rightward, and the axial force F3 generated by the diversion trench 12 is rightward, so that the resultant force is equal to f=f1-F2-F3, the direction of the resultant force F is still leftward, but for the axial force when the diversion trench 12 is not arranged, the value of the axial force is reduced by F3, the pressure generated by the high-speed motor rotor to the axial bearing is reduced, the axial bearing load threshold is increased by phase change, and the safety coefficient of the whole machine is improved.

Meanwhile, the cooling structure of the air compressor increases the air pressure in the motor cavity during cooling, supplements the running air source of the dynamic pressure air bearing, can improve the performance of the dynamic pressure air bearing, and ensures the high-efficiency and safe running of the bearing.

The cooling structure of the air compressor can improve the overall heat exchange quantity and heat exchange efficiency of a heat dissipation system of the whole air compressor, solve the problem of difficult heat dissipation points of a rotor of a high-speed motor and a stator of the high-speed motor, improve the heat exchange environment of the whole air compressor, and on the basis, the added air guide fan can provide a part of axial force, so that the axial force of the rotor to the primary compression side of the whole air compressor is reduced in the rotating process of the rotor, namely the bearing capacity required by an air bearing of the whole air compressor is reduced, the bearing area is improved by phase change, and further the reliability and the service life of the whole air compressor are improved.

In some embodiments, the first shaft 19 is located within the housing 11 near the first compression assembly, the outer wall of the second shaft 22 has an inclined section that is inclined along the shaft sleeve 20 toward the centerline of the second shaft 22, and the flow guide groove 12 is located at the inclined section. In this solution, the guide groove 12 is located in the inclined section. When the directional cooling airflow is guided to enter the motor cavity, the diversion trench can also provide a part of smaller axial force, so that the axial force of the rotor of the high-speed motor to the primary compression side is reduced in the rotating process of the rotor, namely, the required bearing capacity of the whole air bearing is reduced, the bearing threshold is improved by phase change, and the guarantee is provided for the stable operation of the rotor under high load.

According to the air compressor cooling structure, the diversion trenches are arranged on the end face of the rotor of the high-speed motor, and the diversion trenches can provide a part of smaller axial force when the cooling air flow is guided into the motor cavity in a directional manner, so that the axial force of the rotor of the high-speed motor to the primary compression side is reduced in the rotating process of the rotor, namely the bearing capacity required by the air bearing of the whole machine is reduced, the bearing threshold is improved by phase change, and the stable operation of the rotor under high load is ensured.

In some embodiments, the cooling assembly includes a cooling flow channel, which is disposed on the housing 11 in a spiral shape, and both ends of the cooling flow channel are communicated with the outside of the housing 11. In this technical scheme, the cooling flow channel is spirally arranged on the shell 11, so that the heat exchange area of the cooling flow channel is increased, the heat exchange efficiency is high, and the cooling flow channel can be an axial water channel flowing up and down. The cooling flow channel can be cooled by liquid cooling or air cooling.

According to the cooling structure of the air compressor, the high-pressure gas at the primary compression side is introduced, and after being cooled by the water cooling circulation system, the high-pressure gas has the characteristics of low temperature and high pressure, so that the gas pressure in a motor cavity can be increased, and the performance of the gas dynamic pressure bearing is improved.

The rotor 9 is connected with the first impeller 2, the thrust disc 5, the diversion trench 12, the second impeller 15 and the diversion trench 12, and is arranged at one end close to the secondary compression side and is positioned in a motor cavity between the second cover 14 and the stator 10.

The working principle is as follows: when the stator 10 is electrified, the high-speed motor rotor 9 is driven to rotate at a high speed, and when the high-speed motor rotor 9 rotates, the high-speed motor rotor 9 is driven to rotate together with the first impeller 2, the thrust disc 5, the diversion trench 12 and the second impeller 15.

When the first impeller 2 rotates, the first volute 1 is matched to perform suction compression on gas. Through the continuous suction of the first impeller 2 and the second impeller 15, the external normal temperature air is forced to enter the housing 11 along the first volute 1 and the second connecting pipe 18 arranged on the first connecting pipe, and the air homogenization is carried out along the cooling channel of the housing 11. After being homogenized, the cooling gas flows from the primary side of the motor to the secondary side of the motor along 6-8 first diversion holes 26 uniformly distributed on the inner wall of the shell 11, and enters a motor cavity near the secondary side at the rear of the motor.

As shown in fig. 1, the diversion trench 12 sends the cooled compressed gas into the channel between the high-speed motor rotor 9 and the high-speed motor stator 10, so that the cooled gas passes through and fills the whole motor cavity, flows to the thrust bearing chambers where the first thrust bearing 4, the high-speed motor thrust disc 5 and the second thrust bearing 6 are located through the second diversion holes 27 preset on the first cover 7, cools the three and supplements the gas dynamic pressure bearing, and finally discharges the cooled gas into the first-stage compression side through the exhaust hole arranged on the first diffuser 3, thereby realizing the efficient and directional flow of the cooling system, effectively improving the heat dissipation conditions of the high-speed motor rotor 9, the high-speed motor stator 10, the first thrust bearing 4, the high-speed motor thrust disc 5, the second thrust bearing 6 and the like, and realizing the efficient air supplement operation of the gas dynamic pressure bearing.

The two-stage compression scheme is characterized in that the two-stage compression scheme is realized through high-speed rotation of the high-speed motor, and the air guide fan on the shell air guide groove and the rotor is arranged, so that the first-stage compressed high-temperature gas is induced to fully exchange heat with the cooling circulating liquid before entering the motor cavity, and meanwhile, the high-speed motor stator and the high-speed motor rotor which have the most serious influence on the operation and the heating of the high-speed motor are oriented, low-temperature and fully cooled, so that the heat accumulation in the high-energy density and high-power compression mechanism is avoided, the abnormal temperature rise of the high-speed motor stator is avoided, and the electromagnetic safety is influenced; the problems of influence on the clearance between the impeller and the volute caused by the extension of a high-speed motor shaft due to high temperature are avoided, namely the problems of performance change of the compressor caused by internal heat accumulation, even the rubbing of the impeller and the volute caused by the shaft extension, the bending effect of a rotor and the like are avoided.

Under the scheme, the primary compressed cooling air with the temperature of 90-110 ℃ can flow through the motor shell firstly by adjusting the cooling air path of the whole machine, and fully exchanges heat with a water channel arranged in the motor shell, and reduces the air temperature to the temperature of cooling water, namely 50-60 ℃; and the motor rotor and the motor stator are effectively cooled through the action of the diversion trench, so that cooling gas entering the motor cavity, the motor stator and the motor rotor can exchange heat efficiently in real time in the operation process of the high-speed motor, the internal heat accumulation is avoided, the efficiency of the whole circulating heat exchange system is improved, and the problem that cooling water cannot cool the high-speed rotor is patched.

It will be readily appreciated by those skilled in the art that the above advantageous ways can be freely combined and superimposed without conflict.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention. The foregoing is merely a preferred embodiment of the present invention, and it should be noted that it will be apparent to those skilled in the art that modifications and variations can be made without departing from the technical principles of the present invention, and these modifications and variations should also be regarded as the scope of the invention.

Claims

1. The cooling structure of the air compressor is characterized by comprising a shell (11), wherein a rotor (9) and a stator (10) are arranged in the shell (11), one end of the rotor (9) is provided with a first compression assembly, an exhaust port of the first compression assembly is communicated with the inside of the shell (11) so that compressed gas enters the shell (11), a cooling assembly is arranged on the shell (11), and the gas entering the shell (11) exchanges heat with the cooling assembly, flows between the rotor (9) and the stator (10) and is discharged from the shell (11); the rotor (9) is provided with a diversion trench (12), and the diversion trench (12) can drive airflow in the shell (11) to flow along the direction of the other end of the rotor (9) towards the first compression assembly.

2. The air compressor cooling structure according to claim 1, wherein a second compression assembly is provided at the other end of the rotor (9), an air inlet (25) is provided on the housing (11), the air inlet (25) is located on the housing (11) near the first compression assembly relative to the second compression assembly, a cooling channel (24) is provided on the housing (11) along the circumferential direction of the housing (11), the cooling channel (24) is communicated with the air inlet (25), a first diversion hole (26) is provided on the housing (11) along the axial direction of the housing (11), a plurality of first diversion holes are uniformly arranged along the circumferential direction of the housing (11), one end of each first diversion hole (26) is communicated with the cooling channel (24), and the other end is communicated with the interior of the housing (11).

3. The air compressor cooling structure according to claim 2, wherein the other end of the first deflector hole (26) is located on the housing (11) near a second compression assembly with respect to the first compression assembly, and the air flow flowing in the first deflector hole (26) flows in a direction toward the first compression assembly after entering between the rotor (9) and the stator (10).

4. The cooling structure of the air compressor according to claim 2, wherein the exhaust port of the first compression assembly is communicated with the suction port of the second compression assembly through a first connecting pipe (17), and the first connecting pipe (17) is communicated with the air inlet (25) through a second connecting pipe (18), so that the air discharged from the first compression assembly at least partially flows into the housing (11).

5. The air compressor cooling structure according to claim 1, wherein the housing (11) has a first end and a second end, the first end is provided with a first cover body (7), the first compression assembly is arranged on the first cover body (7), a groove is arranged on the first cover body (7), a first thrust bearing (4) and a second thrust bearing (6) are respectively arranged on two side walls of the groove, a thrust disc (5) is arranged on the rotor (9), the thrust disc (5) is at least partially positioned in the groove, and the thrust disc (5) is positioned between the first thrust bearing (4) and the second thrust bearing (6), so that air flow flowing through the rotor (9) can flow into the groove.

6. The cooling structure of the air compressor according to claim 5, wherein a second diversion hole (27) is provided on the first cover body (7) along the axial direction of the rotor (9), a plurality of second diversion holes (27) are uniformly arranged along the circumferential direction of the rotor (9), one end of each second diversion hole (27) is communicated with the groove, the other end of each second diversion hole is communicated with the inside of the casing (11), an air outlet (23) is provided on the first cover body (7), and air flowing into the grooves is discharged out of the casing (11) through the air outlet (23).

7. The air compressor cooling structure according to claim 1, wherein the rotor (9) comprises a first shaft (19), a shaft sleeve (20), a middle section (21) and a second shaft (22), the middle section (21) is located between the first shaft (19) and the second shaft (22), the middle section (21), the first shaft (19) and the second shaft (22) are at least partially sleeved in the shaft sleeve (20), the guide grooves (12) are arranged on the second shaft (22) along the axial direction of the second shaft (22), a plurality of guide grooves (12) are arranged along the circumferential direction of the second shaft (22), and when the rotor (9) rotates, the guide grooves (12) can drive airflow in the shell (11) to flow along the second shaft (22) towards the first shaft (19).

8. The air compressor cooling structure according to claim 7, wherein the first shaft (19) is located in the housing (11) near the first compression assembly, the outer wall of the second shaft (22) has an inclined section, the inclined section being inclined along the shaft sleeve (20) toward the center line direction of the second shaft (22), and the flow guide groove (12) is located at the inclined section.

9. The cooling structure of the air compressor according to claim 1, wherein the cooling assembly includes a cooling flow passage which is spirally provided on the housing (11), both ends of the cooling flow passage being communicated with the outside of the housing (11).

10. An air compressor characterized by comprising the air compressor cooling structure of any one of claims 1 to 9.