KR102018229B1 - Rotor for electric motor - Google Patents

Abstract

The present invention relates to a rotor of an electric motor capable of directly cooling a permanent magnet. The rotor of the electric motor comprises: a rotor core having a plurality of permanent magnet accommodation units provided inside; a plurality of permanent magnets individually accommodated in the plurality of permanent magnet accommodation units; a rotation shaft having a hollow hole unit inside and coupled to a center unit of the rotor core; and a plurality of first cooling paths having one side connected to the inside of the rotation shaft and the other side connected to the permanent magnet accommodation unit, and inducing oil flowing into the hollow hole unit of the rotation shaft to the permanent magnet accommodation unit to be sprayed onto the permanent magnet. A demagnetization occurrence of the permanent magnet can be prevented and a coercive force of the permanent magnet can be increased.

Description

ROTOR FOR ELECTRIC MOTOR

The present invention relates to a rotor of an electric motor that can directly cool heat generated in a permanent magnet with oil.

In general, an electric motor is composed of a stator and a rotor, and the rotor is a device that generates mechanical energy such as rotational power as electrical energy rotates with respect to the stator by electromagnetic interaction.

Since the permanent magnet used in the rotor overheats the potato (감자) occurs, the coercive force and magnetic flux density are lowered and the motor output is lowered, so research and development for cooling the permanent magnet are necessary.

According to the prior art patent document (Patent Publication 10-2014-006688) by forming a cooling flow path adjacent to the rotor inside the rotating shaft, it is possible to heat exchange in the rotor and drive the hybrid vehicle to increase the cooling effect in the center of the rotor A motor heat radiating device is disclosed.

On the other hand, Figure 1 is a conceptual diagram showing a cooling passage formed in the rotating shaft in the prior prior patent document.

The cooling flow path 1 is formed inside the rotating shaft 2, and the permanent magnet 4 is embedded in the rotor 3 inside. The cooling passage 1 is spaced apart from the permanent magnet 4, and the oil introduced into the cooling passage 1 is indirectly exchanged with the permanent magnet 4 in an indirect manner.

However, since the oil flowing along the cooling flow path 1 is heat-transferd in contact with the permanent magnet 4, the cooling efficiency is low and there is a limit in increasing the cooling performance.

The present invention has been made to solve the conventional problems, the rotor of the electric motor that can be cooled by contacting the oil directly to the permanent magnet provided with a cooling flow path that oil can flow into the permanent magnet in the middle of the rotor core The purpose is to provide.

In order to achieve the above object, the rotor of the motor according to the present invention, the rotor core having a plurality of permanent magnet receiving portion therein; A plurality of permanent magnets respectively accommodated in the plurality of permanent magnet accommodation portions; A rotary shaft having a hollow portion therein and coupled to a central portion of the rotor core; And one side is in communication with the inside of the rotating shaft, the other side is in communication with the permanent magnet receiving portion, and a plurality of first cooling passages for injecting oil introduced into the hollow portion of the rotating shaft to the permanent magnet receiving portion and injecting the permanent magnet. It includes.

According to an example related to the present invention, the rotor core may be formed by stacking a plurality of electrical steel sheets and the plurality of first cooling passages may be formed on at least one or more electrical steel sheets of the plurality of electrical steel sheets.

According to an example related to the present invention, the plurality of first cooling passages may be disposed in the middle along the axial direction of the rotor core and spaced apart from each other along the axial direction.

According to an example related to the present invention, each of the plurality of first cooling passages may extend along a radial direction of the rotor core.

According to an example related to the present invention, the plurality of first cooling passages may be spaced apart along the circumferential direction of the rotor core.

According to an example related to the present invention, each of the plurality of permanent magnet accommodation parts accommodates the plurality of permanent magnets disposed to be inclined in symmetry, and receives the oil introduced through the first cooling channel to the plurality of permanent magnets. Can be distributed in both directions.

According to an example related to the present invention, the rotor core may further include a plurality of second cooling passages extending in the axial direction from the plurality of first cooling passages, respectively.

According to an example related to the present invention, the end ring may further include an end ring mounted to both ends of the rotor core, and one end may be in communication with the second cooling channel, and the other end may be in communication with the outside of the end ring. It is formed, and may be provided with an injection passage extending inclined in the thickness direction of the end ring to inject the oil toward the end turn of the stator coil disposed outside the end ring.

According to an example related to the present invention, the oil may be introduced into the hollow portion of the rotating shaft by an oil pump.

According to an example related to the present invention, the plurality of permanent magnets may form a plurality of poles, and the first cooling passage may be formed one per pole.

According to an example related to the present invention, the first cooling passages are formed one per two poles, and the rotor core includes a plurality of intermediate plates in which the first cooling passages are located along the axial direction of the rotor core. Are spaced apart from each other in the axial direction, and each of the plurality of intermediate plates may be alternately disposed to have the first cooling passages having a phase difference of a predetermined angle along the circumferential direction.

According to an example related to the present invention, the rotor core may include a plurality of rotor core units, and the plurality of rotor core units may be disposed to have a phase difference of a predetermined angle along the circumferential direction.

According to an example related to the present invention, the rotation shaft may include a plurality of communication passages extending in a radial direction to communicate the hollow portion and the first cooling passage.

Referring to the effect of the rotor of the electric motor according to the invention as follows.

First, by providing a cooling passage through which oil can pass in the electrical steel sheets stacked in the middle of the plurality of electrical steel sheets forming the rotor core, oil introduced into the rotating shaft may flow into the permanent magnet accommodating portion through the cooling passage. .

Second, the oil introduced into the permanent magnet receiving portion can directly prevent the generation of potatoes by heat by directly cooling the permanent magnet, and can improve the output of the electric motor by improving the magnetic flux density of the permanent magnet and improve the magnetic flux.

1 is a conceptual view showing a cooling passage formed in a rotating shaft in the prior art document.
Figure 2 is a perspective view showing the appearance of the rotor of the electric motor according to the first embodiment of the present invention.
3 is a cross-sectional view taken along III-III in FIG. 2.
4 is a conceptual diagram illustrating a cross section taken along IV-IV in FIG. 3.
5 is a conceptual diagram illustrating an intermediate plate in FIG. 4.
6 is a cross-sectional view illustrating a movement path of oil in FIG. 3.
7 is a conceptual diagram illustrating an oil movement path in which oil is circulated by an oil pump.
8 is a conceptual view showing a permanent magnet receiving hole formed in another electrical steel sheet according to a second embodiment of the present invention.
9 is a conceptual diagram illustrating a permanent magnet accommodating part and a first cooling passage formed in an intermediate plate according to a second embodiment of the present invention.
10 is a conceptual diagram illustrating first and second intermediate plates according to a third embodiment of the present invention.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, and the same or similar components are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used in consideration of ease of specification, and do not have distinct meanings or roles from each other. In addition, in describing the embodiments disclosed herein, when it is determined that the detailed description of the related known technology may obscure the gist of the embodiments disclosed herein, the detailed description thereof will be omitted. In addition, the accompanying drawings are intended to facilitate understanding of the embodiments disclosed herein, but are not limited to the technical spirit disclosed herein by the accompanying drawings, all changes included in the spirit and scope of the present invention. It should be understood to include equivalents and substitutes.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, the terms "comprises" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Figure 2 is a perspective view showing the appearance of the rotor 10 of the electric motor according to the first embodiment of the present invention, Figure 3 is a cross-sectional view taken along III-III in Figure 2, Figure 4 is a IV-IV in Figure 3 5 is a conceptual view showing a cross section taken along, FIG. 5 is a conceptual view showing an intermediate plate 114 in FIG. 4, FIG. 6 is a cross-sectional view showing a movement path of oil in FIG. 3, and FIG. 7 is an oil by the oil pump 18. This is a conceptual diagram showing the circulating oil movement path.

The rotor 10 of the present invention may be rotatably provided in the stator 17.

The rotor 10 includes a rotor core 11 and a permanent magnet 12.

The rotation shaft receiving hole 110 extends in the axial direction and penetrates inside the rotor core 11.

The rotating shaft 13 is inserted through the rotating shaft receiving hole 110 and coupled with the rotor core 11, and the rotating shaft 13 and the rotor core 11 may be configured to rotate together. The rotary shaft 13 may have a hollow portion 130 formed therein along the axial direction.

The rotor core 11 may be formed by stacking and joining a plurality of electrical steel plates 113 having a circular shape.

Each of the plurality of electrical steel plates 113 includes a permanent magnet receiving hole 111, a rotating shaft receiving hole 110, and a through hole 112.

The rotating shaft receiving hole 110 may be formed at the center of the electrical steel sheet 113 to accommodate the rotating shaft 13.

Permanent magnet receiving hole 111 is formed in the electrical steel sheet 113, it can accommodate the permanent magnet 12. Permanent magnet receiving hole 111 may be disposed in a plurality of spaced apart in the circumferential direction around the outer periphery of the rotation axis receiving hole (110).

Each of the plurality of permanent magnet receiving holes 111 may have a narrow width and a penetrating shape in the shape of a rectangular hole (Hole) having a relatively long length compared to the width.

Each of the plurality of permanent magnet receiving holes 111 is symmetrical with respect to an imaginary extension line connecting the center and the outer circumferential portion of the electrical steel sheet 113 along the radial direction and extends obliquely in a direction protruding toward the center from the outer circumferential portion Can be.

Permanent magnet 12 receiving holes symmetric with each other may be formed to correspond to two sides of the same length and adjacent to each other in an isosceles triangle.

Permanent magnet receiving hole 111 symmetric with each other may be arranged in a plurality of spaced apart in each radial direction.

Each of the plurality of permanent magnet receiving holes 111 symmetric with each other, one end portion is disposed adjacent to each other in the circumferential direction toward the center of the electrical steel sheet 113, the other end is adjacent to the outer peripheral portion of the electrical steel sheet 113 And may be spaced apart from each other along the circumferential direction.

The plurality of permanent magnets 12 symmetric with each other may form one pole.

The plurality of permanent magnets 12 may form eight poles. The plurality of permanent magnets 12 may alternately form the N pole and the S pole along the circumferential direction.

The through hole 112 may be formed to penetrate along the thickness direction of the electrical steel sheet 113, and may be spaced apart along the circumferential direction between the permanent magnet receiving hole 111 and the rotating shaft receiving hole 110.

End rings 14 are mounted at both ends of the rotor core 11 to prevent the permanent magnets 12 inserted into the permanent magnet receiving holes 111 from falling out in the axial direction.

The plurality of permanent magnets 12 may be in direct contact with the oil and may be directly cooled by transferring heat generated from the permanent magnet 12 to the oil.

The oil may be circulated along the circulation passage and contact the plurality of permanent magnets 12.

The housing 15 has a cylindrical shape and is open at both sides along the axial direction, and may be configured to accommodate the stator 17 therein. End cover passages 160 are fastened to both end portions of the housing 15, and are configured to cover both sides of the housing 15, respectively.

The bearing mounting portion 162 may protrude from the inner side surface of the end cover passage 160, and the bearing 161 may be mounted inside the bearing mounting portion 162. The rotating shaft 13 may be rotatably supported by the bearing 161.

An end of the rotating shaft 13 may be accommodated inside the bearing mounting portion 162 through the bearing 161.

The stator 17 may include a stator core 170 and a stator coil 171 wound around the stator core 170.

The circulation passage includes an internal circulation passage via the rotation shaft 13 and the rotor core 11, and an external circulation passage through the housing 15 and the end cover passage 160.

The inner circulation flow path includes a hollow portion 130 formed inside the rotation shaft 13, a plurality of first cooling flow paths 1141 formed along the radial direction inside the rotor core 11, and the rotor core 11. It may be configured to include a plurality of second cooling passages (1131) formed along the axial direction in the interior.

A plurality of communication passages 131 for supplying oil to the inside of the rotor core 11 may be formed in the middle along the longitudinal direction of the rotation shaft 13.

Each of the plurality of communication passages 131 extends in a radial direction, one side of each communication passage 131 communicates with the hollow portion 130, and the other side of each communication passage 131 is the first of the rotor core 11. It may be formed in communication with the cooling passage 1141.

The plurality of communication passages 131 may be spaced apart along the circumferential direction of the rotation shaft 13. The plurality of communication passages 131 may be eight.

Each of the plurality of first cooling passages 1141 extends along a radial direction of the rotor core 11, and one side of each of the first cooling passages 1141 communicates with the communication passage 131 and each first cooling passage ( The other side of the 1141 may be connected to the permanent magnet receiving portion 1142 through the through-hole 112.

The plurality of first cooling passages 1141 may be spaced apart from each other along the circumferential direction of the rotor core 11 and may be formed of eight.

The permanent magnet accommodating part 1142 may be formed in a fan shape to accommodate the permanent magnet 12 therein and to receive the oil so that the oil may come into contact with the permanent magnet 12.

Four plate-shaped permanent magnets 12 are disposed on the inside and outside of the rotor core 11 to be inclined symmetrically in the permanent magnet accommodating part 1142.

The first cooling passage 1141 and the permanent magnet accommodating portion 1142 may be disposed in the middle along the axial direction of the rotor core 11. The plurality of first cooling passages 1141 and the permanent magnet accommodating portion 1142 may be spaced apart along the axial direction of the rotor core 11.

The plurality of first cooling passages 1141 and the permanent magnet accommodating part 1142 may be formed on at least one or more electrical steel sheets of the plurality of electrical steel sheets 113 forming the rotor core 11.

The intermediate plate 114 may be named to distinguish the electrical steel sheet 113 on which the plurality of first cooling passages 1141 and the permanent magnet accommodating portion 1142 are formed from other electrical steel plates 113. For example, the intermediate plate 114 may be formed to a thickness of about 2 ~ 3mm by stacking a plurality of electrical steel sheet.

The intermediate plate 114 is different from other electrical steel plates 113 in that a plurality of first cooling passages 1141 are further provided on the electrical steel sheets.

In addition, the permanent magnet receiving portion 1142 of the intermediate plate 114, unlike the permanent magnet receiving hole 111 of the other electrical steel plate 113, the permanent magnet 12 and the permanent magnet 12 by widening the contact area as much as possible And to absorb as much heat as possible from.

That is, the permanent magnet accommodating part 1142 of the intermediate plate 114 accommodates four permanent magnets 12 in one space, but in four permanent magnets 12 radially spaced and inclined in left and right symmetry. Are configured to be open to one another with respect to each other. As a result, the plurality of permanent magnets 12 accommodated in the permanent magnet receiving portion 1142 of the intermediate plate 114 may be in contact with the maximum amount of oil.

On the other hand, the permanent magnet receiving hole 111 of the other electrical steel sheet (113) accommodates only one permanent magnet 12 in one space, four permanent magnets 12 are radially spaced and inclined in left and right symmetry Are configured to close to each other with respect to. As a result, the permanent magnet receiving hole 111 of the other electrical steel sheet 113 may individually increase the strength of the permanent magnet 12 by wrapping the permanent magnet 12 embedded in the rotor core 11. .

The plurality of first cooling passages 1141 and the permanent magnet accommodating portion 1142 may be spaced apart along the circumferential direction of the intermediate plate 114. In this embodiment, eight first cooling passages 1141 and the permanent magnet receiving portion 1142 are formed.

The permanent magnet receiving hole 111 of the other electrical steel sheet 113 is a cooling flow path groove 1132 for forming a part of the second cooling passage 1131 at an end inclined in the direction protruding toward the rotating shaft receiving hole 110. It is provided. Cooling flow path groove 1132 may be formed in the remaining portion of the permanent magnet receiving hole 111 is not filled with the permanent magnet 12.

The second cooling flow path 1131 is formed by the permanent magnet receiving hole 111 of the electrical steel sheet 113 adjacent to each other along the axial direction or the thickness direction is in communication with each other along the axial direction of the rotor core (11).

The inner circulation passage may further include a plurality of injection passages 140 formed inside the end ring 14.

The plurality of injection passages 140 may extend inclined radially outward with respect to the thickness direction of the end ring 14. The plurality of injection passages 140 may be spaced apart along the circumferential direction of the end ring 14.

According to the inclined structure of the injection passage 140, oil is injected toward the stator 17 disposed in the radially outer side of the rotor core 11, and more specifically, to the end turn 1711 of the coil of the stator 17. The stator 17 coil can be cooled.

The external circulation passage may include a housing passage 150 formed in the housing 15 and an end cover passage 160 formed in the end cover passage 160.

The oil may be circulated by receiving circulation power from the oil pump 18.

An oil inlet is formed on the bottom of the housing 15, and the oil inlet is connected to the housing flow path 150.

The oil pump 18 may be mounted at one side of the housing 15 and configured to pump and circulate the oil introduced through the oil inlet to the housing flow path 150.

The housing 15 has a first nozzle 151 branched from the housing flow path 150 to inject oil into an end turn 1711 of the stator coil 171 protruding out of the stator core 170. And a second nozzle 152 branched to spray oil from the housing flow passage 150 toward the rotation shaft 13.

The first nozzle 151 and the second nozzle 152 may be disposed above the housing 15. The second nozzle 152 may be spaced apart from the first nozzle 151 in the axial direction and formed on a downstream side of the first nozzle 151.

The end cover passage 160 extends in the radial direction of the housing 15, one side thereof is connected to the second nozzle 152, and the other side passes through the bearing mount portion 162 along the radial direction to form a bearing mount portion ( It may be connected in communication with one end of the rotary shaft 13 accommodated inside the 162.

The oil cooling action according to the cooling structure of the rotor core 11 will be described.

When the oil pump 18 is operated, the oil pump 18 sucks oil into the housing flow path 150 through the oil inlet of the housing 15 and raises the oil along the housing flow path 150. The oil moving along the housing flow path 150 cools the housing 15.

The oil raised to the upper portion of the housing 15 passes through the end cover passage 160 flow path from the second nozzle 152 branched from the housing flow passage 150, and the hollow part of the rotating shaft 13 by the oil pump 18. Flows into 130.

Oil introduced into the hollow portion 130 of the rotating shaft 13 is formed through the communication passage 131 of the rotating shaft 13 along the radially outward direction of the hollow portion 130 by centrifugal force due to the rotation of the rotating shaft 13. 1, it moves to the cooling passage 1141.

Subsequently, the oil flows into the permanent magnet accommodating portion 1142 from the first cooling passage 1141, and the oil introduced into the permanent magnet accommodating portion 1142 is injected between two permanent magnets 12 adjacent to the left and right. The sprayed oil is sprayed into two permanent magnets 12 adjacent to the left and right radially inwardly by hitting and reflecting two permanent magnets 12 radially spaced apart, and the oil is in contact with the permanent magnet 12. The permanent magnet 12 can be cooled directly.

The oil absorbed heat from the permanent magnet 12 is moved in both directions along the second cooling passage 1131, and the rotor through the injection passage 140 of the end ring 14 is installed at both ends of the rotor core (11) It is injected toward the end turn 1711 of the stator coil 171 disposed on the radially outer side of the core 11. In this case, the injected oil may cool the stator coil 171.

8 is a conceptual view showing a permanent magnet receiving hole 111 formed in another electrical steel sheet 213 according to the second embodiment of the present invention, Figure 9 is an intermediate plate 214 according to the second embodiment of the present invention. A conceptual diagram illustrating the formed permanent magnet accommodating part 1142 and the first cooling passage 2141.

Another electrical steel sheet 213 according to the second embodiment includes a plurality of permanent magnet receiving holes 111 spaced apart in the circumferential direction; Rotating shaft receiving hole 110 is formed in the center of the circular; And a plurality of through-holes 112 spaced apart in the circumferential direction between the permanent magnet receiving hole 111 and the rotary shaft receiving hole 110.

Cooling flow path grooves 1132 are formed at lower ends of the plurality of permanent magnet accommodation holes 111, and the plurality of other electrical steel plates 213 are laminated and bonded in the axial direction so that the plurality of cooling flow path grooves 1132 are formed in the second direction. The cooling flow path 1131 may be formed.

The plurality of permanent magnet accommodation holes 111 may be formed to accommodate two permanent magnets 12 per pole. The plurality of permanent magnets 12 may form eight poles.

Each of the two permanent magnet receiving holes 111 per pole is formed to be inclined left and right symmetrically with respect to the virtual center line connecting the center of the rotation axis receiving hole 110 and the outer peripheral portion of the electrical steel sheet 113 in the radial direction, each permanent magnet One end of the accommodation hole 111 may be disposed adjacent to the rotational shaft accommodation hole 110, and the other end of each permanent magnet accommodation hole 111 may be disposed adjacent to the outer circumferential portion of the electrical steel sheet 113.

One flux barrier 1133 may be formed between two permanent magnet receiving holes 111 so as to extend in a direction perpendicular to the radial direction.

The intermediate plate 214 according to the second embodiment may be located in the middle along the axial direction of the rotor core 11. The intermediate plate 214 may be formed by stacking a plurality of electrical steel sheets.

The intermediate plate 214 may be spaced apart along the axial direction in plurality. The intermediate plate 214 may include a plurality of permanent magnet receiving portions 2142 spaced apart along the circumferential direction; Rotating shaft receiving hole 110 is formed in the center of the circular; A plurality of through holes 112 spaced apart in the circumferential direction between the permanent magnet accommodating part 2142 and the rotating shaft accommodating hole 110; And a plurality of first cooling passages 2141 extending in a radial direction so that both ends thereof communicate with the permanent magnet receiving portion 2142 and the rotating shaft receiving hole 110.

The plurality of permanent magnet receiving portions 2142 may include a neck portion 2142a, a body portion 2142b, and an arm portion 2142c. The neck portion 2142a is connected in communication with one end of the first cooling passage 2141, and the arm portion 2142c is inclined to both sides at an interval of about 90 degrees from the neck portion 2142a toward the outer circumference of the intermediate plate 214. Can be. The body portion 2142b may be formed to have a wide area along the radial direction at the neck portion 2142a.

Each of the plurality of permanent magnets (eg, two per pole) has one end accommodated in the neck portion 2142a, and is spaced apart at a first interval in the circumferential direction, and the other end is accommodated in the arm portion 2142c, but is made in the circumferential direction. It may be spaced apart by two intervals. The first interval is formed narrower than the second interval.

The oil moves along the first cooling passage 1141 from the rotary shaft accommodating hole 110 by centrifugal force, and is ejected from the neck portion 2142a to the interior of the permanent magnet accommodating portion 2142, thereby providing a permanent magnet accommodating portion 2142. By being sprayed on the plurality of permanent magnets 12 accommodated on both sides, the permanent magnets 12 can be directly cooled.

After cooling the permanent magnet 12, the oil moves in the axial direction along the cooling flow path groove 1132 of the other electrical steel plate 113 communicated along the axial direction in the neck 2142a to be discharged out of the rotor core 11. Can be.

The oil discharged out of the rotor core 11 may be collected at the bottom of the housing 15 and may be circulated by the oil pump 18 through the oil inlet to the housing flow path 150.

The first embodiment in that the permanent magnet receiving hole 111 of the other electrical steel sheet 213 and the permanent magnet receiving portion 2142 of the intermediate plate 214 accommodates two permanent magnets 12 per pole. Although there is a difference in the examples, other configurations may be applied to the same or similar to the first and second embodiments.

10 is a conceptual diagram illustrating first and second intermediate plates 314a and 314b according to a third embodiment of the present invention.

The rotor core 11 according to the third embodiment may be composed of a plurality of rotor core units 311.

The plurality of rotor core units 311 may be configured in five stages. Each of the plurality of rotor core units 311 may be arranged to have a predetermined angle, for example, a phase difference θ1 of 1 to 5 degrees along the circumferential direction.

First and second intermediate plates 314a and 314b may be disposed at both ends of the third-stage rotor core unit 311 positioned in the middle of the five-stage rotor core unit 311.

Each of the first and second intermediate plates 314a and 314b includes a plurality of permanent magnet accommodation portions 3314 spaced apart along the circumferential direction; Rotating shaft receiving hole 110 is formed in the center of the circular; And a plurality of first cooling passages 3141 extending in a radial direction so that both ends thereof communicate with the permanent magnet receiving portion 3142 and the rotational shaft accommodation hole 110. A plurality of through-holes 112 may be spaced apart along the circumferential direction between the permanent magnet receiving portion (3142) and the rotation axis receiving hole (110). The first cooling passage 3141 may extend radially across the through hole 112.

Each of the first and second intermediate plates 314a and 314b may have one first cooling passage 1141 per two poles. When a plurality of permanent magnets 12 are installed in the rotor core 11 with eight poles, eight permanent magnet receiving portions 3142 may be provided in each of the first and second intermediate plates 314a and 314b, and eight first magnets may be provided. Four cooling passages 3141 may be formed.

In each of the first and second intermediate plates 314a and 314b, four first cooling passages 3141 may be formed by crossing each pole along the circumferential direction. The four first cooling passages 3141 may be spaced apart from each other by a 45 degree gap along the circumferential direction.

In addition, the first cooling passage 3141 of the first intermediate plate 314a and the first cooling passage 3141 of the second intermediate plate 314b have a phase difference of a predetermined angle, for example, a phase difference θ2 of 45 degrees. And can be staggered with each other.

According to this configuration, the intermediate plate 314 according to the third embodiment may increase rigidity as the number of first cooling passages 3141 decreases.

In addition, in order to increase the rigidity of the intermediate plate 314, the outer edge of the permanent magnet receiving portion (3142) may be further provided with a reinforcing portion (3143) protruding in the radial direction.

Therefore, according to the present invention, a cooling passage for inducing oil is provided in the rotor core 11, and the permanent magnet 12 can be directly cooled by injecting oil into the permanent magnet 12.

In addition, by directly cooling the permanent magnet 12, it is possible to prevent the generation of potatoes by the heat of the permanent magnet 12, it is possible to increase the cooling efficiency.

In addition, by preventing the generation of potatoes of the permanent magnet 12, the coercive force of the permanent magnet 12 can be stably maintained, and further, the output of the electric motor can be improved.

10: rotor 11: rotor core
110: rotating shaft receiving hole 111: permanent magnet receiving ball
112: through hole 113: electrical steel sheet
1131: second cooling flow path 1132: cooling flow path home
1133: flux barrier 114: intermediate plate
1141,2141,3141: First cooling flow path
1142: permanent magnet housing 12: permanent magnet
13: rotating shaft 130: hollow part
131: communication path 14: end ring
140: injection passage 15: housing
150: housing euro 151: first nozzle
152: second nozzle 16: end cover
160: end cover euro 161: bearing
162: bearing mounting portion 17: stator
170: stator core 171: stator coil
1711: end turn 18: oil pump
214: intermediate plate 2142,3142: permanent magnet housing
2142a: neck 2142b: trunk
2142c: arm part 311: rotor core unit
314a: first intermediate plate 314b: second intermediate plate
3143: reinforcement

Claims (13)

A rotor core having a plurality of permanent magnet accommodation parts and a plurality of permanent magnet accommodation balls therein;
A plurality of permanent magnets accommodated in the plurality of permanent magnet accommodation portions and the plurality of permanent magnet accommodation holes, respectively;
A rotary shaft having a hollow portion therein and coupled to a central portion of the rotor core; And
One side is in communication with the interior of the rotary shaft, the other side is in communication with the permanent magnet receiving portion, the plurality of first cooling passages for injecting oil introduced into the hollow portion of the rotary shaft to the permanent magnet receiving portion to the permanent magnet Including,
The plurality of permanent magnet receiving portion,
Lower both sides extending from the other side of the first cooling channel and symmetrically symmetrically with respect to a center line extending radially of the rotation axis along the first cooling channel; And
An upper both side spaced in the radial direction of the rotation axis from the lower both sides and inclined left and right about the center line
Is a polygon containing
The plurality of permanent magnet accommodation hole is inclined horizontally and symmetrically at the same angle as the lower both sides, and forms a cooling flow path groove in the remaining portion where the plurality of permanent magnets are not accommodated,
The cooling passage groove is a rotor of the electric motor, characterized in that for forming a second cooling passage extending in the axial direction of the rotating shaft in the plurality of first cooling passages. The method of claim 1,
The rotor core is formed by laminating a plurality of electrical steel sheets,
And the plurality of first cooling passages are formed on at least one or more electrical steel sheets of the plurality of electrical steel sheets. The method of claim 1,
The plurality of first cooling passages are located in the middle along the axial direction of the rotor core, the rotor of the electric motor, characterized in that spaced apart from each other along the axial direction. The method of claim 1,
Each of the plurality of first cooling passages extends in a radial direction of the rotor core. The method of claim 1,
And the plurality of first cooling passages are spaced apart along the circumferential direction of the rotor core. delete delete The method of claim 1,
Further comprising an end ring mounted to both ends of the rotor core,
The end ring is,
One side is in communication with the second cooling passage, the other side is formed in communication with the outside of the end ring, in the thickness direction of the end ring to spray oil toward the end turn of the stator coil disposed outside of the end ring A rotor of an electric motor, characterized by comprising a spray passage extending obliquely. The method of claim 1,
The oil is a rotor of the electric motor, characterized in that flowing into the hollow portion of the rotating shaft by an oil pump. The method of claim 1,
The plurality of permanent magnets form a plurality of poles,
The rotor of the electric motor, characterized in that the first cooling passage is formed one per pole. The method of claim 10,
The first cooling flow path is formed one per two poles,
The rotor core may include a plurality of intermediate plates in which the first cooling passages are positioned along the axial direction of the rotor core, spaced apart along the axial direction, and each of the plurality of intermediate plates may be arranged around the first cooling passage. The rotor of the electric motor, characterized in that the staggered arrangement with each other to have a phase difference of a predetermined angle along the direction. The method of claim 1,
The rotor core includes a plurality of rotor core unit,
And the plurality of rotor core units are arranged to have a phase difference of a predetermined angle along the circumferential direction. The method of claim 1,
The rotation shaft includes a plurality of communication passages extending along the radial direction to communicate the hollow portion and the first cooling passage.

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