CN115549350A - Compressor and motor thereof - Google Patents

Abstract

The invention provides a compressor and a motor thereof. Wherein the motor includes a housing; a stator fixed inside the housing; a rotor rotatably disposed inside the stator; and a cooler mounted to the stator and configured to introduce a cooling medium outside the housing and then spray the cooling medium to an outer circumferential surface of the rotor to cool the rotor. The invention can apply good cooling to the rotor, so that the motor efficiency is higher.

Description

Compressor and motor thereof

Technical Field

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

Background

The permanent magnet synchronous motor is widely applied to the field of compressors, in particular to refrigeration compressors such as centrifugal compressors, screw compressors and the like. The high-speed permanent magnet synchronous motor mostly adopts a surface-mounted permanent magnet which is attached to a rotor spindle to form a rotor, and then the position of the rotor is fixed by a metal or carbon fiber sheath.

However, the higher rotation speed of the permanent magnet synchronous motor for the compressor leads to larger eddy current loss and wind friction loss of the permanent magnet or the metal sheath, and particularly, the refrigeration compressor is more obvious. In the prior art, the motor is cooled mainly by utilizing the natural flow of a cooling medium in an air gap between a stator and a rotor or adopting a water cooling motor shell, so that the stator has a certain cooling effect, but the high rotating speed of the rotor causes higher flow resistance of the cooling medium, and the heat conductivity coefficient of a gaseous cooling medium is also lower, so that the cooling effect of the motor rotor is poor, and the high-speed running efficiency and the reliability of the motor are influenced.

Disclosure of Invention

An object of the present invention is to solve or at least partially solve the above problems of the prior art, and to provide a compressor motor which can apply good cooling to a rotor;

a further object of the invention is to provide more uniform cooling throughout the axial direction of the rotor.

Another object of the present invention is to provide a compressor having the above motor.

In one aspect, the present invention provides a motor of a compressor, including:

a housing;

a stator fixed inside the housing;

a rotor rotatably disposed inside the stator; and

a cooler mounted to the stator and configured to introduce a cooling medium outside the housing and then spray the cooling medium to an outer circumferential surface of the rotor to cool the rotor.

Optionally, the cooler comprises:

the central axis of the annular header pipe is parallel to the axial direction of the stator and is arranged at one axial end of the stator;

the liquid inlet pipe is connected with the annular main pipe so as to inject the cooling medium into the annular main pipe; and

and a plurality of branch pipes extending from the respective circumferential positions of the annular header pipe and provided at the inner circumferential position of the stator so as to extend in the axial direction of the stator, each of the branch pipes being provided with a plurality of injection holes for injecting the cooling medium toward the outer circumferential surface of the rotor.

Optionally, the end of each branch pipe connected to the annular header pipe is a first end, and the other end is a second end; the flow cross section of each branch pipe is gradually increased in the direction from the first end to the second end.

Optionally, the end of each branch pipe connected with the annular main pipe is a first end, and the other end is a second end; the aperture of the injection hole of each branch pipe is gradually increased in a direction from the first end to the second end.

Optionally, each of the branch pipes is embedded at a notch of a core of the stator.

Optionally, each of the branch pipes has a cross-sectional shape matching the notch so as to be inserted into the notch in a unique posture.

Optionally, each of the branch pipes is rotatably connected to the annular manifold with an axis of rotation parallel to its length for fitting into the slot at an optimal attitude.

Optionally, a groove is formed in an inner circumferential surface of each tooth of the iron core of the stator, and the groove penetrates through two axial end faces of the tooth.

Optionally, the housing seals the stator and the rotor inside, the main shaft protruding through an opening in the end of the housing to connect to the compression section of the compressor;

the shell is provided with a liquid inlet for introducing the cooling medium and a discharge port for discharging the cooling medium, and the cooler is communicated with the liquid inlet to introduce the cooling medium; and is

The liquid inlet is connected with a throttling device of the refrigeration system, the cooling medium flowing into the liquid inlet is a throttled refrigerant, and the discharge port is communicated with an evaporator of the refrigeration system.

In another aspect, the present invention also provides a compressor including the motor as described in any one of the above.

In the motor of the compressor, the cooler is arranged on the stator, and introduces the cooling medium outside the motor shell and sprays the cooling medium to the outer peripheral surface of the rotor, so that the outer peripheral surface of the rotor which is difficult to cool by adopting a conventional mode is cooled, the cooling effect of the rotor is very good, and the motor has higher operation efficiency and better reliability.

Furthermore, in the motor, the cooler comprises the annular main pipe and the branch pipes, the annular main pipe is arranged at one axial end of the stator, and the branch pipes extend along the axial direction of the stator at the inner peripheral part of the stator, so that the branch pipes can extend into the motor to cool the rotor and do not occupy extra space. Moreover, the cooler utilizes a plurality of branch pipes to spray in all directions, and the coverage area is very large. Therefore, the cooler is very practical and ingenious in structural design.

Further, the present invention recognizes that the branch pipe has a greater internal pressure closer to its inlet (first end) and a lesser internal pressure further away from the inlet. Therefore, in the direction from the first end to the second end of the branched pipe, the flow cross section of the branched pipe is gradually increased, or the aperture of the perforation of the branched pipe is gradually increased, so that the injection flow rates of the injection holes at all positions in the length direction of the branched pipe are consistent or have smaller difference, the cooling at all positions in the axial direction of the rotor is more uniform, the cooling effect is better, and the unfavorable thermal deformation is avoided.

Furthermore, in the motor, the inner peripheral surface of each tooth of the stator core is provided with a groove, and the grooves penetrate through two axial end surfaces of the teeth, so that the turbulence degree of an air gap between the stator and the rotor can be improved, the heat conduction between the outer peripheral surface of the rotor and an air gap piece is accelerated, and the cooling speed of the rotor is accelerated.

Furthermore, in the motor of the compressor, the main shaft of the rotor is provided with a central flow passage and a plurality of dispersion holes. After the cooling medium enters the central flow passage, the main shaft and the permanent magnet directly connected with the main shaft are cooled in the flowing process along the central flow passage, so that the motor rotor is cooled, the motor efficiency is higher, and the reliability is better.

In addition, during the rotation of the main shaft, the cooling medium with higher temperature in the central flow passage, which cools the main shaft, is thrown out of the main shaft by the plurality of flow dispersing holes through centrifugal action, so as to allow new cooling medium to continuously enter the central flow passage. Therefore, the cooling scheme of the invention promotes the cooling medium to continuously flow along the axial direction of the main shaft, so that the cooling effect is better.

The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof, taken in conjunction with the accompanying drawings.

Drawings

Some specific embodiments of the invention will be described in detail hereinafter by way of example and not by way of limitation with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:

FIG. 1 is a schematic cross-sectional view of an electric machine according to one embodiment of the present invention;

FIG. 2 is a schematic view of the construction of the cooler of the present invention;

FIG. 3 is a schematic view of the assembled structure of the stator and the cooler of the present invention;

FIG. 4 is a schematic left side view of FIG. 3;

FIG. 5 is an enlarged view at A of FIG. 4;

FIG. 6 is a schematic view of another embodiment of the stator;

FIG. 7 is an enlarged view at B of FIG. 6;

fig. 8 is a schematic view of a structure of a rotor in the motor shown in fig. 1;

FIG. 9 is a schematic view of the construction of the spindle in the present invention;

FIG. 10 is another angular schematic view of the spindle shown in FIG. 9;

FIG. 11 is a schematic view of the structure of a through-flow ring in the present invention;

FIG. 12 is a schematic view of the assembly of the main shaft and the through flow ring;

FIG. 13 is an enlarged cross-sectional view of the structure of FIG. 12 taken along the flow annulus;

FIG. 14 is a schematic view from another perspective of the structure shown in FIG. 13;

fig. 15 is a partial schematic view of a motor at its thrust bearing according to an embodiment of the present invention.

Detailed Description

A motor and a compressor according to an embodiment of the present invention will be described with reference to fig. 1 to 15. In the description of the present embodiments, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", "clockwise", "counterclockwise", etc. indicate orientations and positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, are not to be construed as limiting the present invention.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature, i.e., one or more such features. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise. When a feature "comprises or comprises" a or some of its intended features, this indicates that other features are not excluded and that other features may be further included, unless expressly stated otherwise.

Unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and "coupled" and the like are to be construed broadly and can, for example, be fixedly connected or detachably connected or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. Those skilled in the art should understand the specific meaning of the above terms in the present invention according to specific situations.

Further, in the description of the present embodiment, the first feature being "on" or "under" the second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature therebetween. That is, in the description of the present embodiment, the first feature being "on", "above" and "over" the second feature includes the first feature being directly above and obliquely above the second feature, or merely means that the first feature is higher in level than the second feature. A first feature "under," "beneath," or "beneath" a second feature may be directly under or obliquely under the second feature or may simply mean that the first feature is at a lesser elevation than the second feature.

Unless otherwise defined, all terms (including technical and scientific terms) used in the description of the present embodiments have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

FIG. 1 is a schematic cross-sectional view of an electric machine according to one embodiment of the present invention; FIG. 2 is a schematic view of the construction of the cooler of the present invention; FIG. 3 is a schematic view of the assembled structure of the stator and the cooler of the present invention; FIG. 4 is a schematic left side view of FIG. 3; fig. 5 is an enlarged view at a of fig. 4, in each of which the axial directions of the motor, the stator, the rotor, and the spindle are denoted by x.

As shown in fig. 1 to 5, a motor for a compressor of an embodiment of the present invention may generally include a housing 10, a stator 20, a rotor 30, and a cooler 60.

The stator 20 is fixed to the inside of the housing 10. The rotor 30 is rotatably disposed inside the stator 20 and includes a main shaft 31 and a permanent magnet 32 fitted thereto. When the stator 20 is energized, magnetic force is generated between the rotor 30 and the stator, and the rotor 30 is driven to rotate. Specifically, the stator 20 includes a stator 20 core 21 and a winding 22, and the stator 20 is generally annular as a whole. The rotor 30 is coaxially disposed at an inner side of the stator 20 with an air gap between an outer circumferential surface of the rotor 30 and an inner circumferential surface of the core 21 of the stator 20, and the main shaft 31 is connected to a compression part of a compressor (e.g., an impeller of a centrifugal compressor) to output torque to the compression part. The permanent magnet 32 can be tile-shaped and is wrapped on the periphery of the main shaft 31, and a fixing sleeve ring 33 is sleeved on the periphery of the permanent magnet 32 to fix the position of the permanent magnet 32.

The casing 10 may be made to seal the stator 20 and the rotor 30 therein, and the main shaft 31 protrudes through an opening of an end of the casing 10 to be connected to a compression part of the compressor. That is, the compressor is of a non-contact type structure, the motor is separately provided in the casing 10, and the main shaft 31 is extended to connect a compression part located outside the motor.

The cooler 60 is mounted to the stator 20 and configured to introduce a cooling medium outside the housing 10 and then spray the cooling medium to the outer circumferential surface of the rotor 30 to cool the rotor 30. The conventional motor cooling structure does not easily cool the outer circumferential surface of the rotor 30, so that the cooling effect of the rotor 30 is not good. The invention utilizes the injection mode to cool the peripheral surface of the rotor 30, so that the cooling effect of the rotor 30 is very good, and the motor has higher operation efficiency and better reliability.

Specifically, as shown in fig. 2, the cooler 60 includes an annular manifold 61, a liquid inlet pipe 62, and a plurality of branch pipes 63. The central axis of the annular manifold 61 is parallel to the axial direction of the stator 20, and is a hollow ring. The annular manifold 61 is arranged at one axial end of the stator 20, for example, in contact with an axial end face of the stator 20. The liquid inlet pipe 62 is connected to the annular manifold 61 to inject the cooling medium into the annular manifold 61. A plurality of branch pipes 63 extend from the annular manifold 61 at various circumferential positions, and communicate with the annular manifold 61. A plurality of branch pipes 63 are provided at an inner circumferential portion of the stator 20 to extend in an axial direction of the stator 20, and each branch pipe 63 is opened with a plurality of injection holes 631 for injecting the cooling medium introduced from the annular header pipe 61 toward an outer circumferential surface of the rotor 30 to cool the outer circumferential surface of the rotor 30. In fig. 2, for simplicity, the injection holes 631 are shown in only one of the branch pipes 63, and the injection holes 631 in the remaining branch pipes 63 are not shown.

In the present embodiment, the branch pipes 63 extend along the axial direction of the stator 20 at the inner circumferential portion of the stator 20, and can extend into the motor to cool the rotor 30 without occupying additional space. Further, the cooler 60 is sprayed in all directions by the plurality of branch pipes 63, and the coverage is very wide. Therefore, the structural design of the cooler is very practical and ingenious.

In some embodiments, as shown in FIG. 2, the end of each branch tube 63 that meets the annular manifold 61 is a first end and the other end is a second end. The inventors have realized that the branch tube 63 has a greater internal pressure closer to its inlet (first end) and a lesser internal pressure further away from the inlet. Therefore, the flow cross section of the branch pipe 63 is gradually increased in the direction from the first end to the second end of the branch pipe 63, in other words, the branch pipe 63 is made thicker as it is farther from the annular header 61, so that the injection flow rates of the injection holes 631 at the respective positions in the longitudinal direction of the branch pipe 63 are made uniform or less different, so that the cooling applied to the rotor 30 is more uniform at all positions in the axial direction, the cooling effect is better, and the occurrence of adverse thermal deformation is avoided.

Similarly, the diameter of the injection hole 631 may be gradually increased in a direction from the first end to the second end of the branch pipe 63. That is, the diameter of the injection holes 631 closer to the first end of the branch pipe 63 is smaller. Similarly, the ejection flow rates of the respective ejection holes 631 at the respective positions in the longitudinal direction of the branch pipe 63 are made uniform or less different.

In some embodiments, as shown in fig. 1, 3 and 5, each of the branch pipes 63 may be fitted at a slot of the core 21 of the stator 20. The stator 20 includes a core 21 and a winding 22, the core 21 is formed with a plurality of teeth 211 uniformly distributed along a circumferential direction thereof, a slot 212 is formed between no adjacent two teeth 211, and the slot 212 is a notch at a region adjacent to an outer circumferential surface of the teeth 211. The embodiment of inserting the branch pipe 63 at the slot does not require any additional space and does not require any modification of the structure of the stator 20.

Further, the cross-sectional shape of each branch pipe 63 can be matched with the notch so as to be inserted into the notch in a unique posture, so that the insertion speed is increased, and the insertion direction error is avoided. It is also possible to have each branch tube 63 rotatably connected to the annular manifold 61 with the axis of rotation parallel to its length to rotate the branch tube 63 to an optimum attitude for better nesting in the slot.

FIG. 6 is a schematic view of another embodiment of the stator 20; fig. 7 is an enlarged view of fig. 6 at B.

As shown in fig. 6 and 7, this embodiment is different from the embodiment of fig. 2 to 5 in that the structure of the core 21 of the stator 20 is improved. The inner peripheral surface of each tooth 211 of the iron core 21 of the stator 20 is provided with a groove 2110, and the grooves 2110 penetrate through two axial end surfaces of the tooth 211 so as to improve the turbulence of an air gap between the stator and the rotor 30, accelerate the heat conduction between the outer peripheral surface of the rotor 30 and the air gap member and accelerate the cooling speed of the rotor 30. The depth h of the groove 2110 ranges from 0.5mm to 1.5mm, and the width c ranges from 1 mm to 3mm.

Fig. 8 is a schematic view of a structure of a rotor in the motor shown in fig. 1; fig. 9 is a schematic view of the structure of the spindle in the present invention.

As shown in fig. 1, 8 and 9, in some embodiments, a central flow passage 310 is formed in the main shaft 31 and extends axially along the main shaft. In other words, the main shaft 31 is opened with an inner hole. The outer peripheral surface of the main shaft 31 is inwardly opened with a plurality of dissipating holes 312 communicating with the central flow passage 310, so that when the main shaft 31 rotates, the liquid cooling medium enters the central flow passage 310 through the inlet 311 thereof to cool the rotor 30, and is then discharged out of the main shaft 31 through the plurality of dissipating holes 312. Specifically, as the main shaft 31 rotates, the liquid cooling medium has a tendency to move radially outward under centrifugal action and thus may exit through the dispersion holes 312. Specifically, the plurality of scattering holes 312 may be located at the same position in the axial direction of the main shaft 31 and may be uniformly distributed in the circumferential direction of the main shaft 31. Of course, the plurality of dispersion holes 312 may be disposed at different positions in the axial direction of the main shaft 31.

In the field of electric motors, in order to cool the electric motor and dissipate heat in time, a cooling medium is generally introduced, and the cooling medium may be refrigeration oil. In the case of a refrigeration compressor, a refrigerant may be used as a cooling medium. However, since the rotor 30 is surrounded by the stator 20, there is less contact with the cooling medium, and the cooling effect is poor. In addition, the main shaft 31 of the motor generates friction with parts such as bearings during rotation, and generates much heat which is difficult to radiate. To solve the problem, in the embodiment of the present invention, the main shaft 31 is particularly configured as a hollow structure, a liquid cooling medium is introduced into the main shaft 31 to cool the main shaft, so that the cooling effect is better, the cooling medium is creatively thrown out by using the air-scattering holes 312, so that the cooling medium can continuously flow in the central flow channel 310, the heat generated by the main shaft 31 can be continuously absorbed and taken away, and the cooling efficiency is higher. In a word, the invention realizes the cooling of the motor rotor 30 by directly cooling the main shaft 31, so that the motor has higher efficiency and better reliability.

In some embodiments, as shown in fig. 1 to 9, the inflow opening 311 and the plurality of diffusing holes 312 are located on a section of the main shaft 31 not covered by the permanent magnet 32 and are respectively located on two sides of the permanent magnet 32 to prevent the permanent magnet 32 from blocking the inflow opening 311 and the diffusing holes 312. Specifically, a first end (a-end) of the main shaft 31 is set as a power output end for connection with a compression part of the compressor. The center flow passage 310 is a blind hole formed inward from the end surface of the second end (b end) of the main shaft 31. The central flow passage 310 is fitted with a sealing plug 39 at the open mouth of the second end of the main shaft 31.

The inlet 311 is located closer to the power output end than the diffuser 312 and opens inward from the outer peripheral surface of the main shaft 31. This configuration avoids the center flow channel 310 from interfering with the inherent configuration (e.g., threaded holes for attachment of the impeller) and structural strength of the power take-off end of the main shaft 31.

In some embodiments, as shown in fig. 1 to 9, the inner wall of the central flow passage 310 is opened with a spiral groove 318 coaxial with the main shaft 31, so that when the rotor 30 rotates, the spiral groove 318 drives the cooling medium at the inflow port 311 to flow toward the plurality of scattering holes 312. At this time, the spiral groove 318 functions as a pump to drive the cooling medium to flow more strongly in the center flow passage 310. In addition, because the spiral groove 318 is formed, the surface shape of the inner wall of the central flow passage 310 is more uneven, the contact surface with the cooling medium is larger, the turbulence degree is higher, sufficient heat exchange with the cooling medium is facilitated, and the cooling effect is better.

In some embodiments, the central channel 310 and the diffusing holes 312 may be circular, and the ratio of the diameter of the diffusing holes 312 to the diameter of the central channel 310 is between 0.3 and 0.35. The inventors have found that such a ratio design allows for better continuity of the flow of the cooling medium in the center flow channel 310 and avoids the need to form larger holes that would affect the strength of the main shaft 31. Further, each of the diverging holes 312 may be gradually inclined from the inside to the outside toward the opposite direction of the rotation direction of the rotor 30 to facilitate throwing out the cooling medium.

In some embodiments, as shown in fig. 1, the housing 10 is opened with a liquid inlet 11 for introducing a cooling medium and a discharge port 12 for discharging the cooling medium. The cooling medium with lower temperature enters the shell 10 from the liquid inlet 11, cools the stator 20 and the rotor 30, increases the temperature, and is discharged from the discharge port 12 to take away the heat generated by the motor.

The refrigeration compressor is applied to a vapor compression refrigeration cycle system which is mainly formed by connecting a compressor, a condenser, a throttle device 80 and an evaporator 90 through pipes to form a circulation circuit in which a refrigerant flows in a circulating manner. In the embodiment of the present invention, preferably, the inlet 11 is connected to the throttling device 80 of the refrigeration system, the cooling medium flowing into the inlet 11 is a throttled refrigerant, and the outlet 12 is communicated with the evaporator 90 of the refrigeration system. In the refrigeration cycle system, the temperature of the refrigerant throttled by the throttling device 80 is the lowest, and the refrigerant is introduced into the housing 10 of the motor to cool the stator 20 and the rotor 30, so that the cooling amplitude of the stator 20 and the rotor 30 is larger, and the cooling strength is larger.

As shown in fig. 1, the motor further comprises two radial bearings 40. The main shaft 31 may be provided with sealing rings at both ends thereof to seal between the openings at both axial ends of the housing 10.

Fig. 10 is another angular view of the spindle 31 shown in fig. 9.

As shown in fig. 1-10, in some embodiments, a thrust disk 315 is formed on the main shaft 31. The motor also includes a thrust bearing 50. The thrust bearing 50 is fitted with a thrust disk 315 for balancing an axial external force of the rotor 30. Specifically, a partial section of the main shaft 31 extends radially outward, and a disk-shaped structure having a larger diameter than the surrounding section is formed as the thrust disk 315, and planes on both sides in the axial direction thereof are thrust surfaces, and the thrust bearing 50 restrains both thrust surfaces so that the main shaft 31 cannot move in the axial direction.

The engagement of the thrust bearing 50 with the thrust plate 315 also generates a relatively large amount of heat during operation of the motor. To this end, in the embodiment of the present invention, at least one thrust surface (two axial planes of the thrust disk are used for bearing axial force, which is called as a thrust surface) of the thrust disk 315 is provided with a plurality of guiding grooves 3150 (the guiding grooves 3150 are marked by hatching in fig. 9 and 10) so as to drive the liquid cooling medium at the thrust surface to flow and be thrown out when the main shaft 31 rotates. The cooling medium cools the thrust disk 315 during the flowing process, which in turn lowers the overall temperature of the rotor 30, resulting in higher motor efficiency and reliability. In addition, because the diversion trench 3150 is arranged, the surface of the thrust surface is more uneven, the contact surface with a cooling medium is larger, the turbulence degree is higher, and the heat exchange effect is better.

Preferably, both thrust surfaces of the thrust disk 315 are formed with a plurality of channels 3150 to enable better cooling on both sides thereof. The guiding grooves 3150 on each thrust surface are uniformly distributed in the circumferential direction of the thrust disk 315, so that cooling at each position of the thrust disk 315 is more uniform. As shown in fig. 9 and 10, each guiding groove 3150 may extend outward from the inner periphery of the thrust surface to the outer periphery of the thrust surface, so that the coverage area of the guiding groove in the radial direction is larger, and the cooling medium on the surface of the thrust surface can be thrown away in time. In addition, each flow guide groove 3150 has a gradually increasing width in a direction extending from the inner periphery to the outer periphery of the thrust surface, so as to facilitate an increase in the flow velocity of the cooling medium. Specifically, both side walls 3151 and 3152 in the width direction of the guiding groove 3150 may extend along the involute curve of the inner circumference of the thrust surface to increase the medium flow speed. The involute curve is gradually inclined in the rotational direction of the main shaft 31 in the direction extending from the inner peripheral edge to the outer peripheral edge of the thrust surface.

The depth of each guiding groove 3150 may be 0.1-0.5 mm, so that the depth of the guiding groove 3150 is more appropriate so as not to affect the strength of the thrust disk 315.

As shown in fig. 1, the thrust bearing 50 is formed with a passage 58 communicating with the discharge port 12 to allow the cooling medium thrown off by the thrust disk 315 to flow to the discharge port 12 through the passage 58.

FIG. 11 is a schematic view of the construction of the flow ring 34 of the present invention; FIG. 12 is a schematic view of the assembly of the main shaft 31 and the flow ring 34; FIG. 13 is an enlarged cross-sectional view of the structure of FIG. 12 taken along the cross-flow ring 34; fig. 14 is a schematic view from another perspective of the structure shown in fig. 13.

In some embodiments, as shown in fig. 1-13, the electric machine includes a stator 20 and a rotor 30. The rotor 30 is rotatably disposed inside the stator 20 and includes a main shaft 31 and a permanent magnet 32 fitted thereto. The main shaft 31 is provided with a central flow passage 310 extending along the axial direction thereof, the outer circumferential surface of the main shaft 31 is provided with a plurality of dispersion holes 312 and at least one inflow opening 311 which are communicated with the central flow passage 310, and the main shaft 31 is sleeved with a through ring 34 at the position of the inflow opening 311. The through-flow ring 34 is provided with a plurality of through-flow suction ports 340, so that when the through-flow ring 34 rotates with the main shaft 31, the liquid cooling medium is sucked into the flow inlet 311, flows in the central flow channel 310 to cool the rotor 30, and is then thrown out of the main shaft 31 by the plurality of scattering holes 312. The plurality of cross-flow suction openings 340 may be evenly distributed along the circumferential direction of the cross-flow ring 34.

In this embodiment, the through-flow ring 34 functions as a pump to promote the cooling medium outside the main shaft 31 to enter the central flow passage 310 at a larger flow rate, so as to ensure a better cooling effect. In addition, the embodiment of the invention makes a series of special designs on the extending direction, shape, width and the like of the cross flow suction opening 340 of the cross flow ring 34, so that the liquid suction capability of the cross flow suction opening 340 is stronger, and a larger flow of cooling medium enters the central flow passage 310.

Specifically, as shown in fig. 13 and 14, each of the cross flow suction ports 340 extends gradually obliquely toward the rotational direction of the cross flow ring 34 in the direction from the inner periphery to the outer periphery of the cross flow ring 34. Further, the width of each of the through-flow suction ports 340 is increased after being decreased in the direction from the inner periphery to the outer periphery of the through-flow ring 34. Specifically, in the rotation direction of the through-flow ring 34, each through-flow suction port 340 is formed such that the front wall 341 facing forward is in a zigzag shape convex in the middle, and the rear wall 342 facing rearward is in a linear shape or a concavely curved shape. This shape enables a larger suction volume and less leakage of the through-flow ring 34.

As shown in fig. 9, 10, 13, and 14, each of the inlets 311 may have a fan shape coaxial with the main shaft 31, and the fan-shaped fan surface may also function to guide the cooling medium into the center flow path 310. The number of the fan-shaped inflow ports 311 may be plural, for example, two, so as to be distributed along the circumferential direction of the main shaft 31.

As shown in fig. 1, the main shaft 31 can be fixedly sleeved with a baffle ring 35 at the position of the diffusing hole 312, and the permanent magnet 32 is sandwiched by the through-flow ring 34 and the baffle ring 35 so that the axial displacement thereof is restrained. The baffle ring 35 is provided with liquid outlet holes 351 which are opposite to the plurality of diffusion holes 312 one by one to allow the cooling medium to flow out.

Fig. 15 is a partial schematic view of a motor of one embodiment of the present invention at its thrust bearing 50.

As shown in fig. 15, in some embodiments of the present invention, the motor includes a housing 10, a stator 20, a rotor 30, and a thrust bearing 50, and a thrust disk 315 is formed on a main shaft 31 of the rotor 30.

The thrust bearing 50 includes two magnetically permeable cores 51, a permanent magnet ring 52, and a non-magnetically permeable ring 53. The two magnetic conductive iron cores 51 are respectively located at two axial sides of the thrust disk 315, are arranged at intervals with two thrust surfaces of the thrust disk 315, and are fixed on the inner wall of the casing 10. The magnetically permeable core 51 may be made of silicon steel sheet or electrical iron. The permanent magnet ring 52 is fixed to the inner wall of the housing 10 so as to be opposed to the outer peripheral surface of the thrust plate 315. The non-magnetic conductive ring 53 is fixed to the inner peripheral surface of the permanent magnet ring 52 and spaced from the outer peripheral surface of the thrust disk 315, and the non-magnetic conductive ring 53 is made of aluminum alloy or copper alloy. The thickness of the non-magnetic conductive ring 53 is greater than or equal to 0.2mm. The magnetic fluid 55 is filled in the gap between the two magnetic conductive iron cores 51, the non-magnetic conductive ring 53 and the thrust disc 315 to form a magnetic loop with the two magnetic conductive iron cores 51, the non-magnetic conductive ring 53 and the thrust disc 315, so that the magnetic fluid 55 is sealed, the leakage of refrigerant and lubricating oil is avoided or reduced, the operation efficiency of the compressor is higher, and the reliability is higher.

As shown in fig. 15, each magnetically permeable core 51 is annular and is fitted over the main shaft 31. Also, the side of each magnetically permeable core 51 facing the thrust face has an annular groove 512 extending around the main shaft 31. The thrust bearing 50 further includes two magnetism isolating rings 54, which are respectively located at two axial sides of the thrust disk 315 and are fixedly sleeved on the main shaft 31. The outer peripheral surface of the end section of each magnetism isolating ring 54 far away from the thrust disk 315 is formed with a plurality of convex rings 541 having a diameter larger than the rest sections of the magnetism isolating ring 54 to block the outflow of the magnetic fluid 55. The height of the bulge ring 541 protruding out of the rest section of the magnetism isolating ring 54 is n, the clearance between the outer circumferential surface of the magnetism isolating ring 54 and the inner circumferential surface of the magnetic conductive iron core 51 is m, and n/m is more than or equal to 0.3 and less than or equal to 0.5.

The root of each thrust surface has a step 3102, and the width of step 3102 is equal to the width of the gap between magnetically permeable core 51 and the thrust surface. One end of each magnetism isolating ring 54 abuts against the end face of the step portion 3102, so that one end face of the magnetic conductive iron core 51 (the end face close to the thrust disk 315) is flush with one end face of the magnetism isolating ring 54. The length of the magnetism isolating ring 54 is greater than the length of the magnetic conductive core 51, so that the other end face of the magnetism isolating ring 54 protrudes out of the other end face of the magnetic conductive core 51, and the projections of the plurality of protruding rings 541 to the magnetic conductive core 51 fall outside the inner circumferential surface of the magnetic conductive core 51, so as to block the magnetic fluid 55.

According to the embodiment of the invention, the shapes, materials, sizes and the like of the magnetic conducting iron core 51, the non-magnetic conducting ring 53, the magnetism isolating ring 54 and the like are optimized, so that the sealing performance of the magnetic fluid 55 sealing structure is better, the operation is more reliable, and the failure rate is lower.

In another aspect, the present invention also provides a compressor, which includes a motor as described in any of the above embodiments, so that the motor drives a compression part of the compressor to compress gas. The compressor may be in the form of a centrifugal compressor, a screw compressor, or the like, and the present invention is not limited to the compressed form thereof.

Thus, it should be appreciated by those skilled in the art that while various exemplary embodiments of the invention have been shown and described in detail herein, many other variations or modifications which are consistent with the principles of this invention may be determined or derived directly from the disclosure of the present invention without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be understood and interpreted to cover all such other variations or modifications.

Claims (10)

1. A motor of a compressor, characterized by comprising:

a housing;

a stator fixed inside the housing;

a rotor rotatably disposed inside the stator; and

a cooler mounted to the stator and configured to introduce a cooling medium outside the housing and then spray the cooling medium to an outer circumferential surface of the rotor to cool the rotor.

2. The electric machine of claim 1, wherein the cooler comprises:

the central axis of the annular header pipe is parallel to the axial direction of the stator and is arranged at one axial end of the stator;

the liquid inlet pipe is connected with the annular main pipe so as to inject the cooling medium into the annular main pipe; and

and a plurality of branch pipes extending from the respective circumferential positions of the annular header pipe and provided at the inner circumferential position of the stator so as to extend in the axial direction of the stator, each of the branch pipes being provided with a plurality of injection holes for injecting the cooling medium toward the outer circumferential surface of the rotor.

3. The electric machine of claim 2,

the end part of each branch pipe connected with the annular main pipe is a first end, and the other end of each branch pipe is a second end;

each branch pipe has a gradually larger flow cross section in a direction from the first end to the second end.

4. The electric machine of claim 2,

the end part of each branch pipe connected with the annular main pipe is a first end, and the other end of each branch pipe is a second end;

each of the branch pipes has an aperture of the injection hole gradually increasing in a direction from the first end to the second end.

5. The electric machine of claim 2,

each branch pipe is embedded in a notch of the iron core of the stator.

6. The electric machine of claim 5,

each of the branch pipes has a cross-sectional shape matched to the notch so as to be inserted into the notch in a unique posture.

7. The electric machine of claim 5,

each of the branch pipes is rotatably connected to the annular header pipe with a rotation axis parallel to a length direction thereof so as to be fitted into the notch at an optimum posture.

8. The electric machine of claim 2,

the inner peripheral surface of each tooth of the iron core of the stator is provided with a groove, and the grooves penetrate through two axial end faces of the teeth.

9. The electric machine of claim 1,

the housing seals the stator and the rotor inside, and the main shaft protrudes through an opening at an end of the housing to connect with a compression part of the compressor;

the shell is provided with a liquid inlet for introducing the cooling medium and a discharge port for discharging the cooling medium, and the cooler is communicated with the liquid inlet to introduce the cooling medium; and is

The liquid inlet is connected with a throttling device of the refrigeration system, the cooling medium flowing into the liquid inlet is a throttled refrigerant, and the discharge port is communicated with an evaporator of the refrigeration system.

10. A compressor, characterized by comprising an electric machine according to any one of claims 1 to 9.

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