CN114069925A - Rotor core, motor and compressor - Google Patents

Rotor core, motor and compressor Download PDF

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Publication number
CN114069925A
CN114069925A CN202010749034.6A CN202010749034A CN114069925A CN 114069925 A CN114069925 A CN 114069925A CN 202010749034 A CN202010749034 A CN 202010749034A CN 114069925 A CN114069925 A CN 114069925A
Authority
CN
China
Prior art keywords
rotor core
rotor
shaft mounting
axial
mounting hole
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010749034.6A
Other languages
Chinese (zh)
Inventor
黄波
赵凤荣
孟祥麒
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Highly Electrical Appliances Co Ltd
Original Assignee
Shanghai Highly Electrical Appliances Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Highly Electrical Appliances Co Ltd filed Critical Shanghai Highly Electrical Appliances Co Ltd
Priority to CN202010749034.6A priority Critical patent/CN114069925A/en
Publication of CN114069925A publication Critical patent/CN114069925A/en
Pending legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/22—Rotating parts of the magnetic circuit
    • H02K1/32—Rotating parts of the magnetic circuit with channels or ducts for flow of cooling medium
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/22—Rotating parts of the magnetic circuit
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/22—Rotating parts of the magnetic circuit
    • H02K1/28—Means for mounting or fastening rotating magnetic parts on to, or to, the rotor structures
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K9/00—Arrangements for cooling or ventilating
    • H02K9/02—Arrangements for cooling or ventilating by ambient air flowing through the machine
    • H02K9/04—Arrangements for cooling or ventilating by ambient air flowing through the machine having means for generating a flow of cooling medium
    • H02K9/06—Arrangements for cooling or ventilating by ambient air flowing through the machine having means for generating a flow of cooling medium with fans or impellers driven by the machine shaft
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K2201/00—Specific aspects not provided for in the other groups of this subclass relating to the magnetic circuits
    • H02K2201/03—Machines characterised by aspects of the air-gap between rotor and stator

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Iron Core Of Rotating Electric Machines (AREA)

Abstract

The invention discloses a rotor core, a motor and a compressor, wherein the rotor core is provided with a driving shaft mounting hole, a plurality of magnet slots and a plurality of refrigerant channels; the driving shaft mounting hole, the magnet groove and the refrigerant channel penetrate through the two axial ends of the rotor core; the driving shaft mounting hole is coaxial with the rotor core, and the plurality of magnet slots and the plurality of refrigerant channels are arranged around the driving shaft mounting hole; an axial-flow type blade is formed between every two adjacent refrigerant channels, the axial-flow type blade is provided with a first curved surface and a second curved surface, and the first curved surface and the second curved surface respectively form the inner walls of the two adjacent refrigerant channels. The invention can reduce the exhaust resistance of the compressor and improve the energy efficiency of the compressor.

Description

Rotor core, motor and compressor
Technical Field
The invention relates to the field of refrigeration equipment, in particular to a rotor core, a motor and a compressor.
Background
The compressor motor comprises a stator and a rotor, wherein the stator is provided with stator teeth, a stator slot is formed between every two adjacent stator teeth, a winding is embedded in the stator slot, and a permanent magnet is inserted in the rotor. The magnetic field generated by the stator winding due to the current and the magnetic field generated by the rotor permanent magnet interact with each other, so that the rotor rotates.
The rotor includes a rotor core, and a coolant through hole is usually formed in the rotor core, and the coolant through hole is an axial straight hole. When the compressor runs at a high speed, the exhaust resistance is increased, the flow coefficient in the refrigerant through hole is small, and the refrigerant through flow is inevitably influenced. In addition, the existing rotor also has the problems of large temperature rise of the rotor, poor oil separation effect and the like caused by large pulsation of refrigerant exhaust pressure and low heat exchange efficiency.
Disclosure of Invention
The present invention is directed to overcome the above-mentioned shortcomings in the prior art, and an object of the present invention is to provide a rotor core, a motor and a compressor, so as to reduce the exhaust resistance of the compressor and improve the energy efficiency of the compressor.
According to an aspect of the present invention, there is provided a rotor core, the rotor core being provided with a driving shaft mounting hole, a plurality of magnet slots, and a plurality of coolant channels; the driving shaft mounting hole, the magnet groove and the refrigerant channel penetrate through the two axial ends of the rotor core; the driving shaft mounting hole is coaxial with the rotor core, and the plurality of magnet slots and the plurality of refrigerant channels are arranged around the driving shaft mounting hole; an axial-flow type blade is formed between every two adjacent refrigerant channels, the axial-flow type blade is provided with a first curved surface and a second curved surface, and the first curved surface and the second curved surface respectively form the inner walls of the two adjacent refrigerant channels.
In one embodiment of the present invention, the axial flow blades are connected to an outer wall of the drive shaft mounting hole and an inner wall of a first cylinder in a radial direction of the rotor core.
In one embodiment of the present invention, the first cylinder is coaxial with the drive shaft mounting hole.
In an embodiment of the present invention, the rotor core is formed by stacking a plurality of rotor sheets, each of the rotor sheets is provided with a plurality of coolant through holes, and each of the coolant through holes is a constituent of one of the coolant channels.
In an embodiment of the present invention, a spacer is formed between two adjacent refrigerant through holes of the rotor sheet, and each spacer is a constituent of one of the axial flow blades.
In an embodiment of the present invention, the spacer has a first end face and a second end face in the axial direction of the rotor core, and the first end face and the second end face of the same spacer do not overlap with each other in a projection along the axial direction of the rotor core.
In an embodiment of the present invention, distances from the respective magnet slots to the rotor core axis are the same.
In an embodiment of the present invention, two sides of each magnet slot in the width direction are respectively provided with a magnetic isolation air gap, and the magnetic isolation air gaps are communicated with the magnet slots.
According to another aspect of the present invention, there is provided an electric machine including the rotor core as described above.
According to still another aspect of the present invention, there is provided a compressor including the motor as described above.
The axial-flow type blades surrounding the driving shaft mounting hole are formed on the rotor core, an axial-flow type refrigerant channel is formed between every two adjacent axial-flow type blades, the through-flow coefficient of the refrigerant channel is large, the through-flow efficiency of the rotor can be remarkably improved, and the exhaust resistance of the compressor is greatly reduced. In addition, because the surface area of the inner wall of the refrigerant channel is greatly increased compared with the prior art, the heat exchange efficiency of the refrigerant can be increased, the temperature of the rotor can be quickly reduced, the separation effect of the refrigerant and oil can be improved, and the energy efficiency of the compressor is integrally improved.
Drawings
Other features, objects and advantages of the present invention will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, with reference to the accompanying drawings.
Fig. 1 is a perspective view of a rotor core according to an embodiment of the present invention.
Fig. 2 is a schematic view of the arrangement of axial flow blades of the rotor core shown in fig. 1.
Fig. 3 is a perspective view of a rotor segment constituting the rotor core shown in fig. 1.
Fig. 4 is a plan view of the rotor sheet shown in fig. 3.
Fig. 5 is an exploded view of a motor including the rotor core shown in fig. 1. And
fig. 6 is a schematic view of a compressor including the motor shown in fig. 5.
Reference numerals
1 rotor core
2 permanent magnet
3 stator core
4 winding
5 drive shaft
6 casing
7 pump body
10 rotor punching sheet
11 drive shaft mounting hole
12 magnet slot
13 refrigerant channel
14 axial flow blade
15 magnetic isolation air gap
16 first cylinder
141 first curved surface
142 second curved surface
103 coolant through hole
104 spacer part
1041 first end face
1042 second end face
Detailed Description
Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their repetitive description will be omitted.
Fig. 1 is a perspective view of a rotor core according to an embodiment of the present invention. Fig. 2 is a schematic view of the arrangement of axial flow blades of the rotor core shown in fig. 1. Fig. 3 is a perspective view of a rotor segment constituting the rotor core shown in fig. 1. Fig. 4 is a plan view of the rotor sheet shown in fig. 3. According to an aspect of the present invention, as shown in fig. 1-4, a rotor core 1 is provided with a driving shaft installation hole 11, a plurality of magnet slots 12 and a plurality of coolant channels 13; the driving shaft mounting hole 11, the magnet slot 12 and the refrigerant channel 13 all penetrate through the two axial ends of the rotor core 1; the driving shaft mounting hole 11 is coaxial with the rotor core 1, and the plurality of magnet slots 12 and the plurality of refrigerant channels 13 are all arranged around the driving shaft mounting hole 11; an axial flow type blade 14 is formed between every two adjacent refrigerant channels 13, the axial flow type blade 14 has a first curved surface 141 and a second curved surface 142, and the first curved surface 141 and the second curved surface 142 form inner walls of the two adjacent refrigerant channels 13 respectively.
Axial flow type blades 14 surrounding the driving shaft mounting hole 11 are formed on the rotor core 1, an axial flow type refrigerant channel 13 is formed between the two adjacent axial flow type blades 14, the through-flow coefficient of the refrigerant channel 13 is large, the through-flow efficiency of the rotor can be obviously improved, and the exhaust resistance of the compressor is greatly reduced. In addition, because the surface area of the inner wall of the refrigerant channel 13 is greatly increased compared with the prior art, the heat exchange efficiency of the refrigerant can be increased, the temperature of the rotor can be quickly reduced, the separation effect of the refrigerant and oil can be improved, and the energy efficiency of the compressor is integrally improved.
Specifically, as shown in fig. 1, the axial flow type blades 14 are connected to the outer wall of the drive shaft mounting hole 11 and the inner wall of a first cylinder 16 in the radial direction of the rotor core 1. The first cylinder 16 is coaxial with the drive shaft mounting hole 11. That is, each of the axial flow blades 14 extends from the drive shaft mounting hole 11 by the same distance in the radial direction of the rotor core 1. Therefore, the through-flow efficiency of the rotor can be obviously improved, and the exhaust resistance of the compressor is greatly reduced.
Fig. 3 is a perspective view of a rotor segment 10 constituting the rotor core 1 shown in fig. 1. As shown in fig. 3, the rotor core 1 is formed by stacking a plurality of rotor sheets 10, each rotor sheet 10 is provided with a plurality of cooling medium through holes 103, and each cooling medium through hole 103 is a constituent part of the cooling medium channel 13. Further, a spacing portion 104 is formed between two adjacent refrigerant through holes 103, and each spacing portion 104 is a constituent of the axial flow blade 14. During assembly, the rotor sheets 10 can be stacked spirally along the axis of the rotor core 1 in a rotating manner, so that each interval portion of the rotor sheets 10 forms a part of one axial flow type blade 14. Further, the mounting holes such as the magnet slots 12 may be machined after the rotor core 1 is assembled.
Fig. 4 is a top view of the rotor sheet shown in fig. 3, and as shown in fig. 4, in the axial direction of the rotor core 1, the spacer has a first end surface 1041 and a second end surface 1042, and the first end surface 1041 and the second end surface 1042 of the same spacer do not overlap with each other along the axial projection of the rotor core 1. Further, the first end surface 1041 and the second end surface 1042 of two axially adjacent spacers 104 have the same size and shape. Thus, when the rotor core 1 is assembled, the rotor sheets 10 may be stacked spirally along the axis of the rotor core 1, so that the spacer 104 may form a part of the axial flow blade 14.
In an embodiment of the present invention, the distances from the magnet slots 12 to the axis of the rotor core 1 are the same. Each magnet slot 12 is distributed around the drive shaft mounting hole 11 at the edge of the rotor core 1. Two sides of each magnet slot 12 in the width direction are respectively provided with a magnetic isolation air gap 15, and the magnetic isolation air gaps 15 are communicated with the magnet slots 12. Because the magnetic permeability of the air is very small, the magnetic isolation air gap 15 can reduce the magnetic leakage phenomenon of the permanent magnet 2, improve the performance of the motor and reduce the noise of the motor. Of course, each magnet slot may be disposed around the driving shaft installation hole 11 in other manners, which is not limited in the present invention.
In summary, the rotor core 1 of the present invention is formed with the axial flow type blades 14 surrounding the driving shaft mounting hole 11, and an axial flow type refrigerant channel 13 is formed between the two adjacent axial flow type blades 14, and the through-flow coefficient of the refrigerant channel 13 is relatively large, so that the through-flow efficiency of the rotor can be significantly improved, and the exhaust resistance of the compressor can be greatly reduced. In addition, because the surface area of the inner wall of the refrigerant channel 13 is greatly increased compared with the prior art, the heat exchange efficiency of the refrigerant can be increased, the temperature of the rotor can be quickly reduced, the separation effect of the refrigerant and oil can be improved, and the energy efficiency of the compressor is integrally improved.
According to another aspect of the present invention, the present embodiment also provides an electric motor including the rotor core 1 as described above. Fig. 5 is an exploded view of a motor including the rotor core 1 shown in fig. 1. As shown in fig. 5, the motor may of course include a stator core 3, a winding 4, a permanent magnet 2, etc., in addition to the rotor core 1. As described above, the rotor core 1 is provided with a driving shaft mounting hole 11, a plurality of magnet slots 12 and a plurality of refrigerant channels 13; the driving shaft mounting hole 11, the magnet slot 12 and the refrigerant channel 13 all penetrate through the two axial ends of the rotor core 1; the driving shaft mounting hole 11 is coaxial with the rotor core 1, and the plurality of magnet slots 12 and the plurality of refrigerant channels 13 are all arranged around the driving shaft mounting hole 11; an axial flow type blade 14 is formed between every two adjacent refrigerant channels 13, the axial flow type blade 14 has a first curved surface 141 and a second curved surface 142, and the first curved surface 141 and the second curved surface 142 form inner walls of the two adjacent refrigerant channels 13 respectively. Other structural features relating to the rotor core may be implemented with reference to the above description. Axial flow type blades 14 surrounding the driving shaft mounting hole 11 are formed on a rotor core 1 of the motor, an axial flow type refrigerant channel 13 is formed between every two adjacent axial flow type blades 14, the through-flow coefficient of the refrigerant channel 13 is large, the through-flow efficiency of the rotor can be remarkably improved, and the exhaust resistance of a compressor is greatly reduced. In addition, because the surface area of the inner wall of the refrigerant channel 13 is greatly increased compared with the prior art, the heat exchange efficiency of the refrigerant can be increased, the temperature of the rotor can be quickly reduced, the separation effect of the refrigerant and oil can be improved, and the energy efficiency of the compressor is integrally improved.
In addition, it should be noted that the motor may also include a balance weight and the like, and the balance weight may be disposed at one end or both ends of the rotor core. However, since it is not the innovative point of the present invention, its specific structure may be designed with reference to the prior art. Therefore, the present invention is not limited thereto, nor is it described in detail herein.
According to still another aspect of the present invention, the present embodiment also provides a compressor. Fig. 6 is a schematic view of a compressor including the motor shown in fig. 5. As shown in fig. 6, the compressor includes the motor as described above. Axial flow type blades 14 surrounding the driving shaft mounting hole 11 are formed on the rotor core 1, an axial flow type refrigerant channel 13 is formed between every two adjacent axial flow type blades 14, the through-flow coefficient of the refrigerant channel 13 is large, the through-flow efficiency of the rotor can be remarkably improved, and the exhaust resistance of the compressor is greatly reduced. In addition, because the surface area of the inner wall of the refrigerant channel 13 is greatly increased compared with the prior art, the heat exchange efficiency of the refrigerant can be increased, the temperature of the rotor can be quickly reduced, the separation effect of the refrigerant and oil can be improved, and the energy efficiency of the compressor is integrally improved.
In addition, in the present embodiment, the compressor is naturally provided with other components than the motor, such as the pump body 7, the housing 6, the accumulator, and the like, which are conventionally used. Since it is not the innovative point of the present invention, its specific structure is designed with reference to the prior art. Therefore, the present invention is not limited thereto, nor is it described in detail herein.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims (10)

1. A rotor core is characterized in that the rotor core is provided with a driving shaft mounting hole, a plurality of magnet slots and a plurality of refrigerant channels; the driving shaft mounting hole, the magnet groove and the refrigerant channel penetrate through the two axial ends of the rotor core; the driving shaft mounting hole is coaxial with the rotor core, and the plurality of magnet slots and the plurality of refrigerant channels are arranged around the driving shaft mounting hole; an axial-flow type blade is formed between every two adjacent refrigerant channels, the axial-flow type blade is provided with a first curved surface and a second curved surface, and the first curved surface and the second curved surface respectively form the inner walls of the two adjacent refrigerant channels.
2. The rotor core of claim 1 wherein said axial flow vanes are connected to an outer wall of said drive shaft mounting bore and an inner wall of a first cylinder in a radial direction of said rotor core.
3. The rotor core of claim 2 wherein said first cylinder is coaxial with said drive shaft mounting bore.
4. The rotor core according to claim 1, wherein the rotor core is formed by stacking a plurality of rotor sheets, each rotor sheet is provided with a plurality of coolant through holes, and each coolant through hole is a constituent of one coolant channel.
5. The rotor core as claimed in claim 4, wherein a spacer is formed between two adjacent refrigerant through holes of the rotor sheet, and each spacer is a component of the axial flow type blade.
6. The rotor core according to claim 5, wherein the spacer has a first end face and a second end face in the axial direction of the rotor core, and the first end face and the second end face of the same spacer do not coincide with each other in a projection in the axial direction of the rotor core.
7. The rotor core of claim 1 wherein each of said magnet slots is equidistant from said rotor core axis.
8. The rotor core according to claim 1, wherein each of the two sides of each of the magnet slots in the width direction is provided with a magnetic isolation air gap, and the magnetic isolation air gaps are communicated with the magnet slots.
9. An electrical machine comprising a rotor core according to any one of claims 1-8.
10. A compressor, characterized by comprising an electric machine according to claim 9.
CN202010749034.6A 2020-07-29 2020-07-29 Rotor core, motor and compressor Pending CN114069925A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010749034.6A CN114069925A (en) 2020-07-29 2020-07-29 Rotor core, motor and compressor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010749034.6A CN114069925A (en) 2020-07-29 2020-07-29 Rotor core, motor and compressor

Publications (1)

Publication Number Publication Date
CN114069925A true CN114069925A (en) 2022-02-18

Family

ID=80227062

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010749034.6A Pending CN114069925A (en) 2020-07-29 2020-07-29 Rotor core, motor and compressor

Country Status (1)

Country Link
CN (1) CN114069925A (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201539409U (en) * 2009-11-12 2010-08-04 上海日立电器有限公司 Discrete rotary-vane splitter plate for closed rotary compressor
CN202586558U (en) * 2012-05-05 2012-12-05 福建福兴电机有限公司 Inner rotation ring air-cooling motor rotor structure
CN106374661A (en) * 2016-10-08 2017-02-01 珠海格力节能环保制冷技术研究中心有限公司 Rotor assembly and motor
CN108194416A (en) * 2018-02-07 2018-06-22 佛山市顺德区新双岭机电科技有限公司 A kind of novel axial-flow leaf
CN207868884U (en) * 2017-12-26 2018-09-14 宁波菲仕自动化技术有限公司 A kind of embedded rotor module of servo motor

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201539409U (en) * 2009-11-12 2010-08-04 上海日立电器有限公司 Discrete rotary-vane splitter plate for closed rotary compressor
CN202586558U (en) * 2012-05-05 2012-12-05 福建福兴电机有限公司 Inner rotation ring air-cooling motor rotor structure
CN106374661A (en) * 2016-10-08 2017-02-01 珠海格力节能环保制冷技术研究中心有限公司 Rotor assembly and motor
CN207868884U (en) * 2017-12-26 2018-09-14 宁波菲仕自动化技术有限公司 A kind of embedded rotor module of servo motor
CN108194416A (en) * 2018-02-07 2018-06-22 佛山市顺德区新双岭机电科技有限公司 A kind of novel axial-flow leaf

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