KR101918065B1 - Electric motor with permanent magnet and compressor having the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor having a permanent magnet and a compressor having the same, wherein the electric motor having the permanent magnet includes a stator; And a rotor provided with a permanent magnet and arranged so as to be rotatable with a predetermined gap with respect to the stator, wherein the permanent magnet has a plurality of magnetic poles arranged alternately along the circumferential direction, A first magnet which is polarized to form a magnetic field in the gap; And a second magnet having a magnetic flux stronger than that of the first magnet and disposed at a center of a plurality of magnetic poles of the first magnet so as to be spaced from the gap with respect to the first magnet, , And the thickness is gradually decreased toward the both ends from the center. Thereby, the cost of the permanent magnet material can be reduced, vibration and noise can be suppressed, and the output of the electric motor can be improved.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an electric motor having a permanent magnet,

The present invention relates to an electric motor having a permanent magnet and a compressor having the electric motor.

As is well known, an electric motor is an apparatus that converts electrical energy into mechanical energy.

Electric motors are classified into direct current, single-phase alternating current, and three-phase alternating current according to the electric supply system.

Such an electric motor generally comprises a stator and a rotor provided to the stator so as to be relatively movable with a predetermined gap therebetween.

Some of the rotors include a rotor core having a rotating shaft, a plurality of conductor bars inserted in the rotor core in the axial direction, and an end ring for shorting the conductor bars.

Another part of the rotor is constituted by a permanent magnet and a rotor frame having a rotating shaft and supporting the permanent magnet.

However, in such a conventional electric motor having a permanent magnet, a magnetic body (back yoke) is provided so as to form a flux path (magnetic path) behind the permanent magnet, thereby increasing the mass of the rotor .

Vibration and noise can be increased when the mass of the rotor is increased.

In addition, when the mass of the rotor is increased, inertia of the rotor is increased, which makes it difficult to control start and stop.

In addition, the magnetic material may be formed of a magnetic steel sheet (or an electromagnetic steel sheet or a silicon steel sheet) having a high magnetic property and a high production cost, so that the manufacturing cost may be increased.

On the other hand, the compressor includes a case, a compression unit provided inside the case to compress the refrigerant, and an electric motor provided inside the case and providing a driving force to the compression unit.

The compression unit includes a cylinder and a roller provided inside the cylinder and connected to the rotation shaft of the electric motor and rotated.

The electric motor includes a stator fixed to the inside of the case and a rotor rotatably installed in the stator around a rotating shaft.

Bearings are provided on both sides along the axial direction of the cylinder so as to rotatably support a rotary shaft protruding to both sides of the cylinder.

However, in such a conventional compressor, the rotor is provided with a rotor core made of a magnetic material and a permanent magnet coupled to the rotor core, so that the mass of the rotor is increased, thereby increasing the vibration and noise. have.

Particularly, since the rotor is supported on one side (one side) by the bearings extending along the axial direction of the rotary shaft, there is a problem that wear of the bearing is greatly increased when the mass and vibration are increased.

In addition, in the case of a so-called surface-mounted permanent magnet type rotor in which permanent magnets are disposed on the outer circumference of the rotor core, expensive permanent magnet materials are required to increase the magnetic flux density of the air gap, There is a problem.

KR 100727028 B1 KR 100567130 B1 KR 100137417 B1

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an electric motor having a permanent magnet capable of suppressing vibration and noise generation and capable of improving the output, and a compressor having the electric motor.

It is another object of the present invention to provide an electric motor having permanent magnets capable of reducing the manufacturing cost by reducing the use of expensive permanent magnets and capable of improving the output, and a compressor having the same.

It is still another object of the present invention to provide an electric motor having a permanent magnet capable of facilitating manufacture of a rotor and a compressor having the same.

It is still another object of the present invention to provide an electric motor having a permanent magnet capable of suppressing the occurrence of damage to the permanent magnet and a compressor having the permanent magnet.

In order to achieve the above object, the present invention provides a stator comprising: a stator; And a rotor provided with a permanent magnet and arranged so as to be rotatable with a predetermined gap with respect to the stator, wherein the permanent magnet has a plurality of magnetic poles arranged alternately along the circumferential direction, A first magnet which is polarized to form a magnetic field in the gap; And a second magnet having a magnetic flux stronger than that of the first magnet and disposed at a center of a plurality of magnetic poles of the first magnet so as to be spaced from the gap with respect to the first magnet, And the thickness of the permanent magnet is gradually decreased toward the both ends from the center.

According to an embodiment of the present invention, the rotor includes a rotary shaft, and a rotor frame concentrically provided between the rotary shaft and the permanent magnet to support the permanent magnet.

According to an embodiment of the present invention, the first magnet includes a second magnet insertion portion into which the second magnet is inserted, and the second magnet insertion portion is formed to have the same thickness as the outer diameter surface of the first magnet .

According to an embodiment of the present invention, the second magnet includes an arc-shaped outer surface portion disposed on the outer side in the radial direction and a linear inner surface portion disposed on the inner side of the outer surface portion.

According to an embodiment of the present invention, the first magnet includes a first magnetic pole part formed with magnetic poles at both ends along a first direction, and a second magnetic pole part formed at opposite ends of the first magnetic pole opposite to the first direction And a second magnetic-pole portion.

According to an embodiment of the present invention, the second magnet is disposed in a boundary region between the first magnetic pole portion and the second magnetic pole portion.

According to an embodiment of the present invention, the second magnet includes an outer surface portion disposed on the outer side in the radial direction and an inner surface portion disposed on the inner side of the outer surface portion, wherein the outer surface portion has a thickness gradually reduced And a thickness decreasing portion formed on the substrate.

According to an embodiment of the present invention, the thickness reducing portion is formed in a linear shape.

According to an embodiment of the present invention, the thickness reducing portion is formed in a curved shape.

According to another aspect of the present invention, there is provided a stator comprising: a stator; And a rotor rotatably disposed at a predetermined gap with respect to the stator, wherein the plurality of magnetic poles are arranged alternately along the circumferential direction, and the plurality of magnetic poles A first magnet being polarly anisotropically magnetized to form a magnetic field in the gap; And a second magnet having a magnetic flux stronger than that of the first magnet and disposed at a center of a plurality of magnetic poles of the first magnet so as to be spaced from the gap with respect to the first magnet, And an outer surface portion corresponding to an outer surface shape of the first magnet.

The rotor includes a rotating shaft and a rotor frame provided between the permanent magnet and the rotating shaft.

According to still another aspect of the present invention, there is provided a stator comprising: a stator; And a rotor having a rotating shaft and a permanent magnet disposed concentrically with the rotating shaft, the rotor being disposed so as to be rotatable about the rotating shaft with a predetermined gap with respect to the stator, wherein the permanent magnet has a circumferential direction A plurality of magnetic poles alternately disposed on the first magnet, and the plurality of magnetic poles are polar anisotropically magnetized to form a magnetic field in the gap; And a second magnet having a magnetic flux stronger than that of the first magnet and disposed at a center of a plurality of magnetic poles of the first magnet so as to be spaced from the gap with respect to the first magnet, And a thickness decreasing portion that gradually decreases in thickness at both ends along the circumferential direction.

According to an embodiment of the present invention, the first magnet is a bonded magnet, and the second magnet is composed of a sintered magnet.

According to an embodiment of the present invention, the rotor frame is made of a non-magnetic material.

According to an embodiment of the present invention, the rotor frame is made of a non-magnetic material made of a lightweight material.

According to an embodiment of the present invention, the rotor frame is formed with at least one penetrating portion penetrating along the axial direction.

According to an embodiment of the present invention, the rotor has eight poles, and the stator includes a plurality of slots and pawls alternately arranged along the circumferential direction, and the plurality of slots are composed of twelve .

According to another aspect of the present invention, A compression unit provided inside the case and compressing the fluid; And a motor provided inside the case and having the permanent magnet for providing a driving force to the compression portion.

As described above, according to the embodiment of the present invention, the permanent magnets of the rotor are arranged such that a plurality of mutually different magnetic poles along the circumferential direction are arranged alternately and the magnetic poles of the first and second magnetic poles By providing the magnet and the second magnet having a magnetic flux stronger than that of the first magnet and disposed in the central portion of the plurality of magnetic poles, the material cost of the permanent magnet can be reduced and the runout can be increased and the output can be enhanced.

Further, since the first magnet is formed in a cylindrical shape and the second magnet having a magnetic flux stronger than that of the first magnet is provided at the central portion of the magnetic pole of the first magnet, the magnetic flux density of the air gap can be changed to a sinusoidal So that the cogging torque can be reduced and the occurrence of vibration and noise can be suppressed.

Further, the first magnet is formed in a cylindrical shape, and a second magnet having a magnetic flux stronger than that of the first magnet is provided at the central portion of the magnetic pole of the first magnet, and the second magnet progressively moves from the center toward both ends It is possible to suppress the reduction in thickness between both ends of the second magnet and the outer diameter surface of the first magnet to suppress the damage of the first magnet.

Further, the second magnet can be disposed closer to the gap, so that the magnetic flux density of the gap can be further increased.

Thereby, the output of the electric motor can be further improved.

The first magnet is formed in a cylindrical shape, and a second magnet having a magnetic flux stronger than that of the first magnet is provided at the central portion of the magnetic pole of the first magnet, and the second magnet corresponds to the outer shape of the first magnet The thickness between the outer surface of the first magnet and the outer surface of the second magnet is kept constant so that the thickness of the first and second magnets, Occurrence of damage of the magnet can be suppressed.

The first magnet is formed in a cylindrical shape, and a second magnet having a magnetic flux stronger than that of the first magnet is provided at the central portion of the magnetic pole of the first magnet, and the second magnet has a thickness By reducing the thickness of the first magnet, it is possible to suppress the damage of the first magnet due to the reduction in thickness between the outer surface of the first magnet and both ends of the second magnet.

Further, since the first magnet is formed of the bonded magnet and the second magnet is constituted of the sintered magnet, the material cost of the permanent magnet can be reduced, and manufacturing can be facilitated.

In addition, since the first magnet is formed of a bonded magnet and the rotor frame is made of a non-magnetic material of a lightweight material, the rotor can be easily manufactured and the manufacturing cost can be reduced.

1 is a cross-sectional view of a compressor including a motor having permanent magnets according to an embodiment of the present invention;
Fig. 2 is a plan view of the stator and rotor of Fig. 1,
3 is an enlarged view of the stator of Fig. 2,
Figure 4 is an enlarged view of the rotor of Figure 1,
Fig. 5 is an enlarged view of the first magnet of Fig. 2,
Fig. 6 is an enlarged view of the second magnet of Fig. 2,
7 is an enlarged view of the main part of Fig. 2,
8 is a modification of the second magnet of Fig. 6,
Fig. 9 is an enlarged view of the rotor frame of Fig. 2,
Fig. 10 is an enlarged view of a coupling region of the first magnet and the second magnet in Fig. 2,
11 is a plan view of a stator and a rotor of an electric motor according to another embodiment of the present invention,
Fig. 12 is an enlarged view of the first magnet in Fig. 11,
13 shows a modification of the permanent magnet of Fig. 11,
14 is an enlarged view of the first magnet of Fig.

Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings. In this specification, the same or similar reference numerals are given to the same or similar components in different embodiments, and the description thereof is replaced with the first explanation. As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. In addition, it should be noted that the attached drawings are only for easy understanding of the embodiments disclosed in the present specification, and should not be construed as limiting the technical idea disclosed in the present specification by the attached drawings.

FIG. 1 is a cross-sectional view of a compressor including a motor having permanent magnets according to an embodiment of the present invention, and FIG. 2 is a plan view of the stator and the rotor of FIG. 1.

As shown in Figs. 1 and 2, a compressor including an electric motor having permanent magnets of this embodiment includes a casing 110; A compression unit 130 provided inside the case 110 and compressing the fluid; And a motor 150 having a permanent magnet according to an embodiment of the present invention, which is provided inside the case 110 and provides a driving force to the compression unit 130.

The case 110 may be configured to form, for example, a receiving space therein.

The case 110 may be configured to have an enclosed accommodation space therein, for example.

The case 110 may include, for example, a cylindrical body 111 and a cap provided to block the opening of the body 111.

The body 111 may be formed to open on both sides, for example.

The cap may be configured to include, for example, a first cap 113 and a second cap 115 for blocking openings on both sides of the body 111.

More specifically, for example, the body 111 is arranged in a vertical direction, the first cap 113 is provided on the body 111, and the second cap 115 is provided on the body 111, As shown in FIG.

A suction pipe 117 may be provided on one side of the case 110.

A discharge pipe 119 may be provided on the other side of the case 110.

Oil 121 may be provided in the case 110.

The oil 121 may be injected at a predetermined height into the inner bottom of the case 110.

The compression unit 130 may be provided in an inner lower region of the case 110.

The suction pipe 117 may be connected to the compression unit 130 to communicate with the compression unit 130.

Accordingly, the refrigerant outside the case 110 can be sucked into the compression unit 130 inside the case 110 through the suction pipe 117.

The refrigerant compressed by the compression unit 130 may be discharged to the outside of the case 110 through the discharge pipe 119.

The compression unit 130 may include, for example, a cylinder 131 having a compression space therein and a roller 135 for rotating the cylinder 131 while compressing the refrigerant.

The cylinder 131 may be formed to open at the upper side and the lower side.

The compression unit 130 may include a main bearing 137 and a sub bearing 139 provided on both sides of the cylinder 131.

The main bearing 137 may be coupled to the cylinder 131 to block the upper side of the cylinder 131, for example.

The sub bearing 139 may be coupled to the lower side of the cylinder 131, for example.

The main bearing 137 may include a blocking portion 138a coupled to block the cylinder 131 and a bearing portion 138b protruding from the blocking portion 138a.

The blocking portion 138a of the main bearing 137 may be fixedly coupled to the inner surface of the case 110, for example.

The sub bearing 139 may include a blocking portion 140a coupled to block the cylinder 131 and a bearing portion 140b protruding from the blocking portion 140a.

The electric motor 150 having a permanent magnet according to an embodiment of the present invention may be provided in the case 110. The electric motor 150 may include a permanent magnet.

The electric motor 150 may include a stator 160 and a rotor 180 rotatably disposed with a gap G set in advance with respect to the stator 160.

The stator 160 may include, for example, a stator core 161 and a stator coil 171 wound around the stator core 161.

The stator core 161 may include a rotor receiving hole 163 in which the rotor 180 is received.

The stator core 161 may be formed, for example, by inserting and stacking an electrical steel plate 162 formed with the rotor accommodating hole 163 in the center thereof.

The rotor 180 may include a rotating shaft 185 and a permanent magnet 190 disposed concentrically with the rotating shaft 185.

The rotor 180 includes a rotating shaft 185, a permanent magnet 190 disposed concentrically with the rotating shaft 185, and a rotor 183 provided between the permanent magnet 190 and the rotating shaft 185. [ And a frame 221 may be provided.

The rotary shaft 185 may have a long length so that one end thereof is connected to the roller 135 and the other end thereof is connected to the rotor frame 221.

A through hole 187 may be formed in the rotating shaft 185.

Accordingly, the oil 121 of the case 110 can be moved upward when the rotary shaft 185 rotates.

An eccentric portion 188 may be formed on the rotary shaft 185.

The roller 135 may be coupled to the eccentric portion 188.

The roller 135 can eccentrically move inside the cylinder 131 when the rotation shaft 185 rotates, and can compress the refrigerant in the cylinder 131.

3 is an enlarged view of the stator of Fig. 2, and Fig. 4 is an enlarged view of the rotor of Fig.

3, the stator core 161 may include a plurality of slots 165 and a plurality of pawls 166 that are alternately formed around the rotor receiving hole 163.

The plurality of slots 165 may be, for example, twelve.

The pawl 166 may be configured with a circumferentially extending pawl 168 at its free end.

The angle of the internal angle θ between the connecting lines L1 and L2 connecting both ends of the pole piece 168 at the center of the stator core 161 is 19.8 to 25.2 degrees Or less.

As shown in FIG. 4, the rotor frame 221 may be provided in an upper region of the rotary shaft 185 spaced from the eccentric portion 188.

The rotor frame 221 may be implemented in a substantially cylindrical shape.

The permanent magnet 190 may be provided on the outer side of the rotor frame 221.

The permanent magnet 190 may include a first magnet 191 disposed on the outer side of the rotor frame 221 and a second magnet 191 disposed on the inner side of the outer surface of the first magnet 191, 211, respectively.

Fig. 5 is an enlarged view of the first magnet of Fig. 2, and Fig. 6 is an enlarged view of the second magnet of Fig. 2. Fig.

The first magnet 191 may have a substantially cylindrical shape as shown in FIG.

The first magnet 191 may be formed of, for example, a bonded magnet.

More specifically, the first magnet 191 may be implemented as a neodymium (Nd) bonded magnet.

The first magnet 191 may have a plurality of magnetic poles (N poles, S poles) alternately arranged along the circumferential direction.

The first magnet 191 may be configured to have, for example, eight poles.

The first magnet 191 may be configured such that a magnetic field is formed in the gap G and a magnetic field is not formed in the first magnet 191.

The first magnet 191 may be polarly anisotropic so that a magnetic field is formed only in the gap G, for example.

The first magnet 191 includes, for example, a first magnetic pole portion 193a formed with magnetic poles (N poles and S poles) at both ends along a first direction, And a second magnetic-pole portion 193b in which different magnetic poles are formed.

More specifically, the first magnet 191 is divided into eight sections along the circumferential direction, and each section may be a pole-anisotropic magnet so that different magnetic poles (N pole and S pole) have.

The first magnet 191 may include, for example, four first magnetic-pole portions 193a and four second magnetic-pole portions 193b.

The first magnetic-pole portion 193a may be polar anisotropic so that, for example, an S-pole is formed at the left end along the first direction (clockwise direction in the drawing) and an N-pole is formed at the right end.

The second magnetic-pole portion 193b may be pole-anisotropic so that, for example, the N-pole is formed at the left end portion and the S-pole is formed at the right end portion opposite to the first direction .

Meanwhile, the second magnet 211 may have a strong magnetic flux to the first magnet 191.

The second magnet 211 may be composed of a sintered magnet.

More specifically, the second magnet 211 may be realized as a neodymium (Nd) sintered magnet.

The second magnet 211 may be spaced from the gap G so as to be spaced apart from the outer surface of the first magnet 191 toward the rotation shaft 185.

More specifically, in the motor 150 having the permanent magnet according to the present embodiment, the first magnet 191 forming the entire magnetic flux is formed by forming a bonded magnet in a cylindrical shape, And is increased by the second magnet 211 disposed in the rear of the first magnet 191 by reducing the total material cost of the permanent magnet 190 can do.

Further, by increasing the magnitude of the runner by the second magnet 211, the magnitude of the counter electromotive force can be increased and the total output can be improved.

In addition, since the magnetic flux density of the air gap G in the gap G is increased by the second magnet 211, the cogging torque can be reduced and the cogging torque can be reduced. One vibration and noise generation can be suppressed.

On the other hand, the second magnet 211 can be preferably as close to the gap G as possible because the main magnet (back electromotive force) can be increased.

As the second magnet 211 is closer to the gap G, the area where the second magnet 211 of the first magnet 191 is coupled is reduced in thickness, so that the support strength is insufficient, The first magnet 191 may be cracked and / or damaged in the thickness reduction region.

To this end, the first magnet 191 is provided with a second magnet inserting portion 195a for inserting the second magnet 211 therein, and the second magnet inserting portion 195a is disposed between the first magnet 191 at a predetermined distance from the outer diameter surface.

The predetermined distance may be a distance between the outer surface of the first magnet 191 and the second magnet inserting portion 195a when the second magnet inserting portion 195a is formed in the first magnet 191, The minimum thickness may be set to a thickness such that cracks or damage of the first magnet 191 may not occur.

The minimum thickness between the outer surface of the first magnet 191 and the second magnet inserting portion 195a may be 1 mm or more.

In consideration of this point, in order to suppress the occurrence of damage due to the reduction in the thickness of the first magnet 191, the thickness of the second magnet 211 is gradually decreased from the center toward both ends Lt; / RTI >

Accordingly, the first magnet 191 can suppress the occurrence of a specific region in which the thickness of the second magnet insertion portion 195a to which the second magnet 211 is coupled is smaller than that of the second magnet insertion portion 195a, The occurrence of cracks or damage in the specific region due to the reduction in thickness of the magnet 191 can be suppressed.

The second magnet 211 may have a length (axial length) corresponding to the axial length of the first magnet 191.

The second magnet 211 may be configured to have, for example, a substantially rectangular parallelepiped shape.

As shown in FIG. 6, the second magnet 211 may have an outer surface 212a corresponding to the outer shape of the first magnet 191.

The second magnet 211 may be configured to include, for example, a curved outer surface portion 212a, a straight inner surface portion 212b, and a straight both side surface portion 212c.

The outer surface 212a of the second magnet 211 may be embodied as an arc having a predetermined radius R2, for example.

Here, the predetermined radius R2 may be set to be smaller than a radius R1 of the first magnet 191, and the centers may be set to be equal to each other.

In response to this, the first magnet 191 may be provided with a second magnet inserting portion 195a so that the second magnet 211 can be inserted therein.

Referring to FIG. 5 again, the second magnet inserting portion 195a may be formed so that its inside is opened along the radial direction.

The second magnet inserting portion 195a includes an outer contact portion that is in surface contact with the outer surface portion 212a of the second magnet 211 and a side contact portion that is in contact with both side surfaces of the second magnet 211 .

The outer surface contact portion of the second magnet inserting portion 195a may be embodied as an arc having a radius R2 corresponding to the radius R2 of the outer surface portion 212a of the second magnet 211. [

The outer surface portion 212a of the second magnet 211 and the outer surface contact portion of the second magnet insertion portion 195a may have the same radius R2 but different assembly tolerances.

More specifically, for example, the outer surface portion 212a of the second magnet 211 has a negative tolerance, and the outer surface contact portion 196a of the second magnet inserting portion 195a has a positive tolerance As shown in FIG.

According to this configuration, the thickness between the outer surface contact portion 196a of the second magnet inserting portion 195a and the outer diameter surface of the first magnet 191 can be made constant.

This makes it possible to suppress the occurrence of a narrow section in which the distance between the outer diameter surface of the first magnet 191 and the second magnet inserting section 195a becomes narrow, It is possible to suppress the occurrence of cracks and damage of the magnet 191.

In addition, since the second magnet 211 strengthens the magnetic flux in the outer section of the relatively thin second magnet inserting section 195a, the potentiometer reliability improvement of the outer section of the second magnet inserting section 195a . ≪ / RTI >

The second magnet inserting portion 195a may be configured such that the center of the second magnet inserting portion 195a is located at the boundary between the first magnetic pole portion 193a and the second magnetic pole portion 193b of the first magnet 191, for example.

The second magnet inserting portion 195a may be symmetrically formed around the boundary between the first magnetic-pole portion 193a and the second magnetic-pole portion 193b.

FIG. 7 is an enlarged view of the main part of FIG. 2, and FIG. 8 is a modification of the second magnet of FIG.

As shown in FIG. 7, the second magnet 211 may have a size corresponding to the size of the pole piece 168 of the stator 160.

More specifically, the second magnet 211 has an internal angle &thetas; between connecting lines L1 and L2 connecting both corners of the inner surface portion 212b and the center of the rotor accommodating hole 163 is 19.8 degrees To 25.2 degrees.

In the present embodiment, the second magnet 211 has a shape in which the edges of both ends of the outer surface portion 212a are not in contact with the connecting lines L1 and L2 but are spaced inward, The second magnet 211a is connected to the connecting lines L1 and L2 connecting the center O of the rotor receiving hole 163 with both ends of the pole piece 168, And may be configured to have inclined side portions 212d formed in parallel.

Fig. 9 is an enlarged view of the rotor frame of Fig. 2;

9, the rotor frame 221 is provided with a second magnet insertion portion 195a which cooperates with the second magnet insertion portion 195a of the first magnet 191 to accommodate the second magnet 211a, (195b).

The second magnet inserting portion 195b of the rotor frame 221 may be formed on the outer surface of the rotor frame 221 so that the second magnet 211 is inserted inward along the radial direction .

The second magnet inserting portion 195b of the rotor frame 221 may be linearly cut so as to be in surface contact with the inner surface portion 212b of the second magnet 211, for example.

The second magnet inserting portion 195b of the rotor frame 221 may be formed of an inner contact portion 196b and a second magnet 211 which are in surface contact with the inner surface portion 212b of the second magnet 211, And a side contact portion 197b that is capable of contacting the both side portions 212c.

A rotating shaft hole 223 may be formed at the center of the rotor frame 221 so that the rotating shaft 195 can be inserted.

The rotor frame 221 may have a penetrating portion 225 penetrating in the axial direction.

The penetrating portion 225 may include a first penetrating portion 226 disposed adjacent to the second magnet inserting portion 195b of the rotor frame 221, for example.

Thus, the temperature rise around the second magnet 211 can be suppressed.

The first penetrating portion 226 may be formed in a circular shape having a predetermined diameter, for example.

The penetrating part 225 may include a second penetrating part 227 formed around the rotating shaft hole 223.

The second through-hole 227 may be, for example, a long hole having a long length in the circumferential direction.

The second penetration portion 227 may be disposed between the first penetration portion 226.

The second penetrating portion 227 may be disposed closer to the rotating shaft hole 223 along the radial direction than the first penetrating portion 226.

The first through-holes 226 may be formed in a number corresponding to the number of the second magnets 211.

The second through-holes 227 may be formed in a number corresponding to the number of the first through holes 226.

Thus, fluid movement on both sides (upper side and lower side in the figure) along the axial direction of the rotor frame 221 can be smooth.

Thus, occurrence of a local temperature variation within the case 110 can be suppressed.

In addition, the mass of the rotor frame 221 can be reduced by the first penetration portion 226 and the second penetration portion 227.

This makes it easy to start and stop the rotor 180.

In addition, the temperature of the periphery of the second magnet 211 can be suppressed by the first penetration portion 226. [

FIG. 10 is an enlarged view of a coupling region of the first magnet and the second magnet of FIG. 2. FIG.

10, the second magnet 211 may be inserted into the second magnet inserting portions 195a and 195b formed by the first magnet 191 and the rotor frame 221. As shown in FIG.

The second magnet 211 is magnetized to have the same magnetic pole (N pole, S pole) as the magnetic pole (N pole, S pole) formed by the first magnetic pole portion 193a and the second magnetic pole portion 193b .

More specifically, if the right end of the first magnetic-pole portion 193a of the first magnet 191 is N-pole, the magnetic pole at the left end of the second magnetic-pole portion 193b also becomes N-pole.

At this time, the second magnet 211 may be magnetized in the thickness direction so that the outer surface portion 212a becomes the N pole and the inner surface portion 212b becomes the S pole.

On the other hand, when the right end of the first magnetic pole portion 193a of the first magnet 191 is the S pole, the magnetic pole at the left end of the second magnetic pole portion 193b also becomes the S pole, May be configured to be magnetized along the thickness direction so that the outer surface portion 212a becomes the S pole and the inner surface portion 212b becomes the N pole.

The rollers 135 may be coupled to the eccentric portion 188 of the rotary shaft 185 and the rollers 135 may be received in the cylinder 131.

The main bearing 137 and the sub bearing 139 may be coupled to the upper side and the lower side of the cylinder 131, respectively.

The first magnet 191 and the second magnet 211 may be coupled to the rotor frame 221 of the rotary shaft 185, respectively.

Here, the adhesive 210 may be appropriately applied to the mutual contact areas of the first magnet 191, the second magnet 211, and the rotor frame 221.

When the operation is started and power is applied to the stator coil 171, the magnetic field formed by the stator coil 171 and the magnetic field formed by the permanent magnet 190 interact with each other, (Not shown).

When the rotor 180 rotates, the roller 135 eccentrically moves inside the cylinder 131, whereby the refrigerant is sucked into the cylinder 131 through the suction pipe 117, The refrigerant can be compressed and discharged to the outside of the cylinder 131.

The compressed refrigerant is discharged to the outside of the case 110 through the discharge pipe 119 and circulated along the refrigerant pipe of the refrigeration cycle.

11 is a plan view of a stator and a rotor of a motor according to another embodiment of the present invention, Fig. 12 is an enlarged view of the first magnet of Fig. 11, Fig. 13 is a modification of the permanent magnet of Fig. 13 is an enlarged view of the first magnet of Fig.

As shown in Fig. 11, the electric motor having the permanent magnet of this embodiment includes a stator 160; And a rotor 180 having a permanent magnet 190 and rotatably disposed with a gap G set in advance with respect to the stator 160. The permanent magnet 190 is disposed along a circumferential direction A plurality of magnetic poles alternately disposed, the plurality of magnetic poles including a first magnet (191) polarized to form a magnetic field in the gap (G); And a plurality of magnetic poles arranged in a center of a plurality of magnetic poles of the first magnet (191) so as to be spaced from the gap (G) relative to the first magnet (191) The second magnet 211b may include a thickness sensing part 215 whose thickness is gradually reduced at both ends of the second magnet 211b along the circumferential direction.

The first magnet 191 may have a cylindrical shape and may be formed of a bonded magnet.

The first magnet 191 may be polarly anisotropic so that a plurality of magnetic poles are formed along the circumferential direction.

The first magnet 191 includes first and second magnetic pole portions 193a and 193b formed at opposite ends thereof with different magnetic poles along the first direction, 193b.

The second magnet 211b may have a rod shape and may be composed of a sintered magnet.

On both ends of the second magnet 211b along the circumferential direction, a thickness-reducing part 215 may be formed to gradually decrease the thickness.

Even if the second magnet 211b further moves toward the gap G, the thickness between the outer surface of the first magnet 191 and the thickness-sensitive portion 215 of the second magnet 211b is narrow Can be suppressed.

According to such a configuration, the second magnet 211b is brought close to the gap G to increase the speed of the runner, whereby the output of the motor 150 can be improved.

In addition, the thickness between the outer diameter surface of the first magnet 211b and the thickness-sensitive portion 215 can be secured to prevent cracking or damage of the first magnet 211b.

The second magnet 211b may include an outer surface portion 212a, an inner surface portion 212b, both side surfaces 212c, and a thick-walled sintered portion 215 having a rectangular shape, for example.

More specifically, the thickness-sensitive portion 215 of the second magnet 211b may be formed in an obliquely cut shape on both sides of the outer surface portion 212a.

The first magnet 191 may include a second magnet inserting portion 195a to allow the second magnet 211b to be inserted therein.

12, the second magnet inserting portion 195a of the first magnet 191 includes an outer contact portion 196a which is in contact with the outer surface portion 212a of the second magnet 211b, An inclined portion 198 formed to be inclined to be in contact with the thickness sensing portion 215 and a side contact portion 197a contacting the both side portions 212c of the second magnet 211b.

As a result, the second magnet inserting portion 195a of the first magnet 191 is formed such that the thickness between the outer diameter surface of the first magnet 191 and the slope portion 198 is set in advance by the slope portion 198 The outer surface portion 212a of the second magnet 211b can be received closer to the gap G without becoming smaller than the predetermined thickness.

According to such a configuration, damage to the first magnet 191 can be suppressed, and the runout of the gap G can be further increased, so that the output of the electric motor 150 can be enhanced.

A second magnet inserting part 195b may be formed in the rotor frame 221 so that the second magnet 211b can be inserted into the second magnet inserting part 195b.

13, the second magnet 211c has a straight outer face portion 212a, an inner face portion 212b and both side face portions 212c, And a curved thick-walled squeeze portion 215a formed so as to be reduced in thickness.

The curved thick-walled recess 215a may be embodied as an outwardly convex circular arc, for example.

The first magnet 191 may include a second magnet inserting portion 195a to allow the second magnet 211c to be inserted therein.

The second magnet inserting portion 195a of the first magnet 191 has an outer surface contact portion 196a that is in contact with the outer surface portion 212a of the second magnet 211c, A curved surface portion 199 formed to be in contact with the thickness sensing portion 215a and a side contact portion 197a contacting the both side surfaces 212c of the second magnet 211c.

The second magnet inserting portion 195a of the first magnet 191 is formed such that the thickness between the outer surface of the first magnet 191 and the curved surface portion 199 is smaller than the thickness The outer surface portion 212a of the second magnet 211c can be received closer to the gap G without being reduced in thickness below the set thickness.

According to such a configuration, damage to the first magnet 191 can be suppressed, and the runout of the gap G can be further increased, so that the output of the electric motor 150 can be enhanced.

A second magnet inserting part 195b may be formed in the rotor frame 221 to insert the second magnet 211c.

The foregoing has been shown and described with respect to specific embodiments of the invention. However, the present invention may be embodied in various forms without departing from the spirit or essential characteristics thereof, so that the above-described embodiments should not be limited by the details of the detailed description.

Further, even when the embodiments not listed in the detailed description have been described, it should be interpreted broadly within the scope of the technical idea defined in the appended claims. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

110: case, 130: compression part, 131: cylinder, 135: roller,
137: main bearing, 139: sub bearing, 150: electric motor, 160: stator,
162: electric steel plate, 163: rotor receiving hole, 165; Slot, 166: pole, 168: poleshoe,
171: stator coil, 180: rotor, 185; 187: through hole, 188: eccentric portion,
190: permanent magnet, 191: first magnet, 193: stimulating portion, 193a,: first stimulating portion,
193b: second magnetic pole portion, 195a, 195b: second magnet inserting portion, 198: inclined portion,
199: curved portion, 210: adhesive
211, 211a, 211b, 211c: second magnet, 212a: outer surface portion, 212b: inner surface portion,
212c, 212d: a side surface portion, 215, 215a:
221: rotor frame, 223: rotating shaft hole, 225:

Claims (15)

Stator; And
And a rotor having a rotating shaft and a permanent magnet disposed concentrically with the rotating shaft, the rotor being rotatable about the rotating shaft with a predetermined gap set to the stator,
Wherein the permanent magnet comprises:
A plurality of magnetic poles formed in a cylindrical shape such that a plurality of magnetic poles are arranged alternately along a circumferential direction, the plurality of magnetic poles being polar anisotropically magnetized to form a magnetic field in the gap; And
And a second magnet having a magnetic flux stronger than that of the first magnet and being respectively disposed at centers of a plurality of magnetic poles of the first magnet so as to be spaced apart from the gap with respect to the first magnet,
Wherein the second magnet is formed in an arc shape so as to gradually decrease in thickness from the center toward both ends,
The first magnet includes a second magnet insertion portion into which the second magnet is inserted,
Wherein the second magnet inserting portion has an arc-shaped outer surface contact portion concentrically spaced apart from an outer diameter surface of the first magnet so as to have the same thickness as the outer diameter surface of the first magnet. Electric motor. delete The method according to claim 1,
Wherein the second magnet has an arc-shaped outer surface portion disposed on an outer side along a radial direction and a linear inner surface portion disposed on an inner side of the outer surface portion. The method of claim 3,
Wherein the first magnet has a first magnetic-pole portion formed with magnetic poles that are different from each other along the first direction at both ends thereof, and a second magnetic-pole portion formed at both ends with different magnetic poles opposite to the first direction,
And the second magnet is disposed in a boundary region between the first magnetic pole portion and the second magnetic pole portion. The method of claim 3,
And the second magnet inserting portion is formed so that the inside of the second magnet inserting portion is opened. The method according to claim 1,
Wherein the second magnet has a size corresponding to the size of the pole piece of the stator. The method according to claim 6,
The stator has a rotor receiving hole in which the rotor is received,
Wherein the second magnet has a sloped side portion formed parallel to a connecting line connecting the center of the rotor receiving hole and both ends of the poles of the stator, respectively. Stator; And
And a rotor having a rotating shaft and a permanent magnet disposed concentrically with the rotating shaft, the rotor being rotatable about the rotating shaft with a predetermined gap set to the stator,
Wherein the permanent magnet comprises:
A plurality of magnetic poles formed in a cylindrical shape such that a plurality of magnetic poles are arranged alternately along a circumferential direction, the plurality of magnetic poles being polar anisotropically magnetized to form a magnetic field in the gap; And
And a second magnet having a magnetic flux stronger than that of the first magnet and being respectively disposed at centers of a plurality of magnetic poles of the first magnet so as to be spaced apart from the gap with respect to the first magnet,
Wherein the second magnet is formed to have an outer surface portion corresponding to an outer surface shape of the first magnet,
The first magnet includes a second magnet insertion portion into which the second magnet is inserted,
Wherein the second magnet inserting portion has an arc-shaped outer surface contact portion concentrically spaced apart from an outer diameter surface of the first magnet so as to have the same thickness as the outer diameter surface of the first magnet. Electric motor. delete 9. The method according to any one of claims 1 to 8,
Wherein the first magnet is a bonded magnet, and the second magnet is a sintered magnet. 11. The method of claim 10,
Wherein the rotor further comprises a rotor frame provided between the rotating shaft and the permanent magnet. 12. The method of claim 11,
Wherein the rotor frame is a non-magnetic material. 12. The method of claim 11,
Wherein at least one penetrating portion penetrating along the axial direction is formed in the rotor frame. 11. The method of claim 10,
The rotor has eight poles,
The stator has a plurality of slots and pawls alternately arranged along the circumferential direction,
And the plurality of slots are twelve (12). case;
A compression unit provided inside the case and compressing the fluid; And
And a motor provided within the case and having a permanent magnet according to any one of claims 1 to 8 for providing a driving force to the compression section.

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