KR101904871B1 - Electric motor with bearing catridge - Google Patents

Abstract

The present invention relates to an electric motor having a bearing cartridge, comprising: a case; A stator housed inside the case; And a rotor assembly rotatably disposed between the stator and the rotor, wherein the rotor assembly includes: a rotating shaft; A rotor coupled to the rotating shaft; A bearing disposed on both sides of the rotor to support the rotation shaft; And a bearing cartridge provided inside the stator and accommodating the rotor and the bearing therein, and aligning the bearing in the axial direction so as to maintain the concentricity. Thereby, both sides of the rotor can be supported and the axial alignment of the bearings can be facilitated.

Description

[0001] ELECTRIC MOTOR WITH BEARING CATRIDGE [0002]

The present invention relates to an electric motor having a bearing cartridge.

As is well known, an electric motor is a device that converts electric energy into mechanical energy.

Such an electric motor typically includes a stator and a rotor rotatably arranged with respect to the stator.

The rotor includes a rotating shaft and a rotor body rotated about the rotating shaft.

The rotary shaft is provided with a bearing for rotatably supporting the rotor.

The bearings are provided on both sides of the rotor.

Some of the rotors are configured with permanent magnets for high efficiency.

In the case of the rotor having the above-described permanent magnet, miniaturization can be achieved by increasing the speed.

However, in such a conventional motor, when the operating speed of the rotor is increased at a high speed for the miniaturization, when the axial alignment of the bearings is shifted, wear of the bearing remarkably increases and life is shortened.

In some cases, for the axial alignment of the bearings, a configuration is disclosed in which a bearing is inserted into a cylindrical cartridge and a spring is inserted between the two bearings.

However, in such a bearing supporting structure of a conventional motor, a bearing cartridge is provided on one side of the rotor to support the rotor on one side, which causes a problem that the support of the rotor becomes insufficient.

In addition, there is a problem that the axial length is increased by the length of the bearing cartridge, making miniaturization difficult.

In addition, since the cooling of the bearing is not easy, the life of the bearing can be shortened.

USUS20120014806 A1 (2012.01.19. Public)

It is therefore an object of the present invention to provide an electric motor provided with a bearing cartridge capable of supporting both sides of the rotor and facilitating axial alignment of the bearings.

Another object of the present invention is to provide an electric motor provided with a bearing cartridge capable of reducing abrasion of a bearing and shortening an axial length thereof.

It is still another object of the present invention to provide an electric motor provided with a bearing cartridge that can facilitate cooling and support of the bearing.

The present invention, in order to achieve the above-mentioned object, comprises a case; A stator housed inside the case; And a rotor assembly rotatably disposed between the stator and the rotor, wherein the rotor assembly includes: a rotating shaft; A rotor coupled to the rotating shaft; A bearing disposed on both sides of the rotor to support the rotation shaft; And a bearing cartridge provided on the inner side of the stator and accommodating the rotor and the bearing therein and axially aligning the bearing so as to maintain the concentricity.

According to an embodiment of the present invention, the bearing cartridge includes: a cylindrical body; And a bearing insertion portion formed at both ends of the body.

According to an embodiment of the present invention, the body is formed with a penetrating portion penetrating the circumferential surface so as to communicate with the inside and the outside.

According to an embodiment of the present invention, the body is formed with a plurality of vent holes through a circumferential surface.

According to an embodiment of the present invention, the body is provided with a plurality of ventilation holes that penetrate the circumferential surface and are inclined with respect to the axial direction.

According to an embodiment of the present invention, the case includes: a case body having one side opened; And a case cover coupled to an opening of the case body.

The case body and the case cover are each provided with a bearing support portion for inserting the bearing insertion portions.

According to an embodiment of the present invention, the stator includes a stator core in which a rotor accommodating space for accommodating the rotor is formed, and a stator coil wound around the stator core, The stator support portion is formed.

According to an embodiment of the present invention, any one of the bearings on both sides of the rotor is slidably inserted into the bearing insertion portion.

According to another aspect of the present invention, there is further provided an elastic member which is brought into contact with a bearing slidably inserted into the bearing insertion portion to apply an elastic force.

According to an embodiment of the present invention, the other one of the bearings on both sides of the rotor is press-fitted into the bearing inserting portion.

According to an embodiment of the present invention, the stator core includes a plurality of pawls projecting toward the rotor, and a slot formed between the pawls and having an opening communicating with the rotor accommodating space.

According to an embodiment of the present invention, the bearing cartridge is provided with a pawl support portion which is in axial contact with the pawl to support the pawl.

According to an embodiment of the present invention, the pawl includes a pole piece extending in a circumferential direction at an end portion of the rotor accommodating space, and the bearing cartridge has an opening penetrating correspondingly to the pole piece.

According to an embodiment of the present invention, the bearing cartridge includes a reinforcing rib projecting radially from the body and inserted into an opening of the slot.

According to an embodiment of the present invention, the bearing support portion is provided with a reinforcing rib insertion groove for inserting the reinforcing rib.

According to an embodiment of the present invention, the bearing cartridge is formed of a synthetic resin member or a ceramic member.

According to an embodiment of the present invention, the rotor includes a rotor core having an outer diameter smaller than an outer diameter of the bearing and coupled to the rotating shaft; And a permanent magnet coupled to the rotor core.

According to an embodiment of the present invention, the permanent magnet is provided on an outer surface of the rotor core, and a cylindrical sleeve is provided on the outer side of the permanent magnet.

As described above, according to the embodiment of the present invention, since the bearing cartridge accommodating the bearings provided on both sides of the rotor and the rotor is provided therein, it is possible to support both sides of the rotor, Can be facilitated.

Thereby, the abrasion of the bearing can be remarkably reduced, and the life of the bearing can be prolonged.

Further, by disposing the rotor between the bearings, a separate space for axial separation of the bearings can be eliminated, and the axial length can be shortened.

This makes it possible to make the motor compact.

Further, by providing the bearing cartridge with a through hole or a vent hole, cooling of the bearing can be facilitated.

Further, by providing the bearing cartridge with the reinforcing rib inserted into the opening area of the slot of the stator, the axial alignment and support of the bearing can be facilitated.

1 is a perspective view of a motor having a bearing cartridge according to an embodiment of the present invention,
Fig. 2 is a sectional view of Fig. 1,
FIG. 3 is an exploded perspective view of FIG. 1,
Fig. 4 is a sectional view of the bearing support region of the case body of Fig. 2,
Figure 5 is a perspective view of the rotor assembly of Figure 2,
Figure 6 is an exploded perspective view of the rotor assembly of Figure 5,
Figure 7 is a cross-sectional view of the rotor assembly of Figure 5,
Figs. 8 and 9 are perspective views of a modification of the bearing cartridge of Fig. 2,
Fig. 10 is a side view of a modification of the bearing cartridge of Fig. 2,
11 is a sectional view of a motor having a bearing cartridge according to another embodiment of the present invention,
Fig. 12 is an exploded perspective view of Fig. 11,
Figure 13 is a perspective view of the rotor assembly of Figure 12,
14 is a perspective view of the bearing cartridge of Fig. 13,
15 is a sectional view of the bearing support portion of the case body 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.

1 to 3, an electric motor 100 having a bearing cartridge according to an embodiment of the present invention includes a case 110; A stator 210 accommodated in the case 110; And a rotor assembly (250) rotatably disposed with a gap between the stator (210) and the rotor assembly (250), the rotor assembly (250) comprising: a rotating shaft (251); A rotor 270 coupled to the rotating shaft 251; A bearing 261 disposed on both sides of the rotor 270 to support the rotation shaft 251; And a bearing cartridge 310 disposed inside the stator 210 and accommodating the rotor 270 and the bearing 261 therein and aligning the bearing 261 in the axial direction so as to maintain the concentricity .

The case 110 may have a receiving space therein.

The case 110 may include a case body 120 and a case cover 160 which are coupled to each other along the vertical direction.

The case body 120 may have, for example, a cylindrical shape with one side (upper side in the drawing) opened.

The case cover 160 may be configured to be coupled to an opening of the case body 120, for example.

The case body 120 may have a disc-shaped bottom portion 122 and a cylindrical portion 132 protruding from the bottom portion 122 and extending in the circumferential direction.

4, a plurality of communication portions 124 are formed in the bottom surface portion 122 of the case body 120 such that the inside and the outside of the case body 120 are communicated with each other .

The case body 120 may be formed with a stator support portion 134 to support the stator 210.

The stator support part 134 may be configured to protrude inward with a width smaller than an outer width of the stator 210, for example.

The stator 210 can be supported by one side (the bottom in the drawing) in contact with the stator support portion 134 along the axial direction.

The stator supporting portion 134 includes a side supporting portion 135 for supporting the outer side (side surface) of the stator 210 and a bottom supporting portion 136 for supporting the bottom surface of the stator 210 can do.

The case body 120 may be provided with a bearing support portion 126 for receiving and supporting a bearing 261 region at one end (lower end portion in the drawing) of the rotor assembly 250.

The bearing support portion 126 of the case body 120 may be formed with a rotation shaft hole 128 through which the rotation shaft 251 can be inserted.

An elastic member 141 may be provided in the bearing support portion 126 of the case body 120 so as to contact the bearing 261 of the rotor assembly 250 to apply an elastic force thereto.

The elastic member 141 may include an elastic member body 142 formed of an elastic member 141 and an elastic protrusion 144 protruding in the thickness direction of the elastic member body 142 (See FIG. 2).

The elastic member 141 has a shape such as, for example, a spring washer, a disc spring, or a washer (an inlaid or external tooth type), and is configured such that a predetermined pre- .

The bearing support portion 126 of the case body 120 may be provided in a central region of the bottom portion 122 of the case body 120.

The case cover 160 includes a cylindrical coupling portion 162 coupled to an opening of the case body 120 and a flat portion 164 reduced in size compared to the bottom portion 122 of the case body 120. [ And a connection part 166 for connecting the coupling part 162 and the flat part 164 in an inclined manner.

The case cover 160 includes an engaging rib 160 protruding in the axial direction and extending in the circumferential direction with an outer diameter reduced along the radial direction so as to be insertable into the inside of the case body 120 163).

The case cover 160 may be provided with a bearing support 171 for receiving and supporting a bearing 261 provided at one end (upper end in the drawing) of the rotor assembly 250.

The bearing support portion 171 of the case cover 160 may be formed with a rotation shaft hole 173 through which the rotation shaft 251 can be inserted.

The bearing support portion 171 of the case cover 160 may be formed on the flat portion of the case cover 160.

A stator 210 may be provided inside the case 110.

The stator 210 may include, for example, a stator core 220 and a stator coil 230 wound around the stator core 220.

The stator core 220 may include a rotor accommodating space 224 in which the rotor assembly 250 is accommodated.

The stator core 220 may be formed by, for example, insulative lamination of a plurality of electrical steel plates 222.

The stator core 220 may include a yoke 225 and a plurality of pawls 226 protruding inwardly in the radial direction from the yoke 225.

The yoke portion 225 may have a ring shape, for example.

The plurality of pawls 226 may be spaced along the circumferential direction of the yoke 225.

A plurality of slots 228 may be formed between the plurality of pawls 226.

The plurality of pawls 226 and the plurality of slots 228 may be alternately formed along the circumferential direction.

The plurality of pawls 226 may each include, for example, a pawl 227 extending in the circumferential direction from the inner end.

The plurality of slots 228 may be formed with openings 229 so as to communicate with the rotor accommodating space 224, respectively.

The openings 229 of the slots 228 may be formed between the poles 227, respectively.

In the present embodiment, the number of the plurality of pawls 226 and the number of the slots 228 are each three, but this is merely an example, and the number thereof can be appropriately adjusted.

5 and 6, the rotor assembly 250 includes a rotating shaft 251, a rotating shaft 251 coupled to the stator 210 and having a predetermined gap in the stator 210, A bearing 261 disposed on both sides of the rotor 270 and a bearing cartridge 310 accommodating the bearing 261 and the rotor 270. The rotor 270 is rotatably arranged, .

The rotation shaft 251 may have a length that can protrude from both sides of the case 110.

The rotation shaft 251 may include a rotor coupling portion 253 to which the rotor 270 is coupled and a bearing coupling portion 254 to which the bearing 261 is coupled.

The rotor coupling portion 253 may have a relatively large diameter and the bearing coupling portion 254 may have a reduced diameter as compared with the rotor coupling portion 253.

The bearing coupling portions 254 may be formed on both sides of the rotor coupling portion 253.

Accordingly, the bearing 261 coupled to the bearing coupling portion 254 can be supported in the axial direction by contacting the end of the rotor coupling portion 253.

The bearing 261 includes, for example, an inner ring 262 into which the rotation shaft 251 is inserted, an outer ring 264 concentrically disposed with the inner ring 262, and the inner ring 262 and the outer ring 264, And a rolling member 266 provided between the first and second rollers 261 and 262.

The rolling member 266 may be composed of, for example, a ball.

In this embodiment, the rolling member 266 is illustrated as a ball, but this is merely an example, and may be a pin or a roller.

The rotor 270 may include a rotor core 271 and a permanent magnet 281 coupled to the rotor core 271, for example, as shown in FIG.

The rotor core 271 may be formed, for example, by laminating a plurality of electrical steel plates 273.

The permanent magnet 281 may be provided on the outer surface of the rotor core 271, for example.

The rotor 270 may include a cylindrical sleeve 285 disposed at the outer periphery of the permanent magnet 281 to support the permanent magnet 281.

The inner surface of the sleeve 285 contacts the outer surface of the permanent magnet 281 to support the permanent magnet 281 so that the permanent magnet 281 can be stably supported at a high speed.

The rotor 270 may include an end cap 287 provided at both ends of the rotor core 271.

Thus, the rotor 270 can be supported in the axial direction.

Meanwhile, the bearing cartridge 310 includes, for example, a cylindrical body 312; And a bearing insertion portion 316 formed at both ends of the body 312.

The body 312 of the bearing cartridge 310 may be formed in a cylindrical shape having at least one side thereof opened along the axial direction, for example.

The body 312 may, for example, be a non-conductive and non-magnetic member.

The body 312 may be made of, for example, a synthetic resin member.

The body 312 may be formed of, for example, a ceramic member.

The body 312 may be formed with a bearing insertion portion 316 so that the bearings 261 can be inserted into both ends of the body 312, respectively.

The bearing 261 may be press-fitted into the bearing insertion portion 316, for example.

The bearing 261 can be slidably inserted into the bearing insertion portion 316, for example.

The bearing 261 is press-fitted into the bearing insertion portion 316 on the upper side of the body 312 of the bearing cartridge 310 in the present embodiment and the bearing insertion portion 316 on the lower side in the figure is fitted with the bearing A case in which the sliding door 261 is slidably coupled will be described as an example. However, this is merely an example, and the present invention is not limited thereto.

The bearing cartridge 310 may be formed with a plurality of through portions 314 penetrating through the bearing cartridge 310 so as to communicate with the inside and the outside.

As a result, the cooling of the bearing 261 and the rotor 270 can be promoted.

The plurality of penetrating portions 314 may have a circumferential length corresponding to the circumferential length of the pole piece 227 along the circumferential direction.

The body 312 may be formed to block the opening 229 of the slot 228 of the stator core 220, for example.

The plurality of through portions may be configured to have an axial length such that the circumferential surface of the rotor 270 may be exposed to the outside.

The bearing cartridge 310 may include a pole support 318 for supporting the pole 226 of the stator core 220.

The pole support 318 may be configured to extend in the radial direction from the outer surface of the body 312 and to be in axial contact with the pawl 226, for example.

The pole supporting portions 318 may be formed below the plurality of through portions 314, for example.

In the present embodiment, the pole supporting portion 318 is formed as a cylindrical shape having an expanded outer diameter of a lower region of the body 312 of the bearing cartridge 310, but this is merely an example, Or in the form of a rib or protuberance which can be brought into contact with the lower end of the lower end 226 (actually the pole 227).

8, the bearing cartridge 320 includes the cylindrical body 312, a bearing insertion portion 316 formed at both ends of the body 312, And a plurality of through portions 314a formed through the body 312. [

In the present embodiment, the plurality of through portions 314a are formed corresponding to the size of the pole piece 227 of the stator core 220, respectively.

That is, the penetration portion 314a may have a size corresponding to the circumferential length and the axial height of the poles 227.

As a result, the size of the plurality of penetrating portions 314a can be reduced, and the strength of the upper region of the body 312 can be improved.

A lower portion of the body 312 may be provided with a pawl support portion 318 having an expanded outer diameter to support the plurality of pawls 226.

9, the bearing cartridge 330 includes a cylindrical body 312, a bearing insertion portion 316 formed at both ends of the body 312, A plurality of through holes 314a formed through the plurality of through holes 314a and a plurality of air holes 332 formed through the peripheries of the plurality of through holes 314a.

Accordingly, the inside and outside of the bearing cartridge 330 are communicated with each other, so that the cooling of the bearing 261 and the rotor 270 can be facilitated.

The plurality of vent holes 332 may be formed with a small size and a small spacing.

10, the bearing cartridge 340 includes a cylindrical body 312, a bearing insertion portion 316 formed at both ends of the body 312, A plurality of through holes 314a formed through the plurality of through holes 314a and a plurality of air holes 332a formed in the periphery of the plurality of through holes 314a so as to have an inclined length.

The plurality of vent holes 332a may be configured to have a slit shape having a long length sloping downward to the right when the inner rotor 270 is rotated in a clockwise direction in the drawing, for example.

As a result, the cooling of the bearing 261 and the rotor 270 can be promoted.

With such a configuration, the bearing 261 can be press-fitted into the bearing cartridge 310.

A rotary shaft 251 provided with another bearing 261 is inserted from the other side of the bearing cartridge 310 and the upper bearing coupling portion 254 is coupled to the upper bearing 261, (250) may be formed.

The elastic member 141 may be inserted into the bearing support portion 126 of the case body 120.

The lower end of the rotor assembly 250 may be inserted into the bearing support portion 126 so that the elastic member 141 and the bearing 261 of the rotor assembly 250 are in contact with each other have.

The stator 210 may be coupled to an upper end portion of the rotor assembly 250 in the drawing.

The stator 210 is relatively moved with respect to the rotor assembly 250 so that the outer surface of the stator 210 is in contact with the stator support portion 134, As shown in FIG.

The pawl support portion 318 of the bearing cartridge 310 contacts the ends of the respective pawls 226 of the stator 210 so that the plurality of pawls 226 can be respectively supported in the axial direction.

When the coupling of the stator 210 is completed, the bearing insert portion 316 on the upper side of the rotor assembly 250 is inserted into the bearing support portion 171 of the case cover 160, Can be coupled to the body (120).

When the case cover 160 is coupled to the case body 120, the bearing 261 on the lower side of the rotor assembly 250 is brought into contact with the elastic member 141, (Preload) can act on the bearing 261 in the axial direction.

Accordingly, a gap (clearance) and / or clearance between the bearings 261 and the rotary shaft 251 can be suppressed.

Thus, vibration and noise generation of the rotating shaft 251 can be suppressed.

In addition, wear of the bearings 261 is suppressed, and the service life can be extended.

Hereinafter, another embodiment of the present invention will be described with reference to Figs. 11 to 15. Fig.

[2]

As shown in Figs. 11 and 12, the electric motor 100a having the bearing cartridge of this embodiment includes a case 110; A stator 210 accommodated in the case 110; And a rotor assembly (250a) rotatably disposed with an air gap between the stator (210) and the rotor assembly (250a), the rotor assembly (250a) comprising: a rotating shaft (251); A rotor 270 coupled to the rotating shaft 251; A bearing 261 disposed on both sides of the rotor 270 to support the rotation shaft 251; And a bearing cartridge 350 provided inside the stator 210 and accommodating the rotor 270 and the bearing 261 therein and aligning the bearing 261 in the axial direction so as to maintain the concentricity .

The case 110 may include, for example, a case body 120 having one side opened and a case cover 160 coupled to an opening of the case body 120.

The case body 120 may be provided with a bearing support part 126 through which one end (lower end in the drawing) of the rotor assembly 250a is inserted and coupled.

The bearing support portion 126 of the case body 120 may be provided with an elastic member 141 that contacts the bearing 261 of the rotor assembly 250a to apply an elastic force.

The case body 120 may be provided with a stator supporting part 134 for supporting the stator 210.

As shown in FIG. 4, for example, the case body 120 may be provided with a plurality of communicating portions 124 penetrating the case body 120 such that the inside and outside of the case body 120 can communicate with each other.

The case cover 160 may be provided with a bearing support portion 171 through which one end (upper end in the drawing) of the rotor assembly 250a is inserted and coupled.

The stator 210 may include a stator core 220 having a rotor accommodating space 224 and a stator coil 230 wound around the stator core 220.

The stator core 220 may have a ring-shaped yoke 225 and a plurality of pawls 226 protruding from the yoke 225 along the radial direction.

The plurality of pawls 226 may each include a pole piece 227 extending in the circumferential direction of the rotor accommodating space 224.

The stator core 220 may have a plurality of slots 228 that are alternately formed with the plurality of pawls 226.

The plurality of slots 228 may each include an opening 229 communicating with the rotor accommodating space 224.

Meanwhile, as shown in FIG. 13, for example, the rotor assembly 250a includes a rotary shaft 251; A rotor 270 coupled to the rotating shaft 251; A bearing 261 disposed on both sides of the rotor 270 to support the rotation shaft 251; And a bearing cartridge 350 provided inside the stator 210 and accommodating the rotor 270 and the bearing 261 therein and aligning the bearing 261 in the axial direction so as to maintain the concentricity .

The rotor 270 may include a rotor core 271 and a permanent magnet 281 coupled to the rotor core 271.

The rotor 270 may be provided on the outer surface of the rotor core 271, for example.

The rotor 270 may include a cylindrical sleeve 285 provided at the outer periphery of the permanent magnet 281 to support the permanent magnet 281.

The rotor 270 may include an end cap 287 disposed at both ends of the rotor core 271.

Thus, the rotor 270 can be supported in the axial direction.

As shown in FIG. 14, for example, the bearing cartridge 350 includes a cylindrical body 312, a bearing 312 formed at both ends of the body 312 so that the bearing 261 can be inserted, And a reinforcing rib 352 protruding along the radial direction from the outer surface of the body 312 and inserted into the opening of the slot 228. [

The bearing cartridge 350 may be formed of, for example, a synthetic resin member or a ceramic member.

The body 312 may be formed with a plurality of penetration portions 314 that correspond to the respective poles 227 of the stator core 220.

The plurality of through portions 314 may be formed to extend from the lower end of the rotor 270 along the axial direction to the lower end of the upper bearing insertion portion 316, for example.

The body 312 protrudes outwardly in a radial direction on one side (lower side in the figure) of the plurality of penetration parts 314 so that the pawl 226 (actually the poles 227) of the stator core 220, And a pawl support portion 318 for supporting the pawl portion 318.

The plurality of reinforcing ribs 352 may protrude radially from the outer surface of the body 312 and may be inserted into the openings 229 of the slots 228 of the stator core 220.

Accordingly, the rigidity of the bearing cartridge 350 is reinforced, and the axial alignment of the bearing 261 can be stably maintained against the action of the external force.

Thus, heat generation and / or wear of the bearing 261 can be remarkably reduced.

Also, the life of the bearing 261 can be extended.

The plurality of reinforcing ribs 352 may extend in the axial direction and have substantially the same length as the body 312.

12 and 15, the bearing support portion 126 of the case body 120 is formed so that one end (lower end in the drawing) of the reinforcing rib 352 is inserted A plurality of reinforcing rib insertion grooves 129 may be provided.

The bearing support portion 171 of the case cover 160 may have a plurality of reinforcing rib insertion grooves 179 each of which is cut so that one end (upper end in the drawing) of the reinforcing rib 352 can be inserted 12).

With this configuration, the bearing 261 can be pressed to one end (upper end in the drawing) of the bearing cartridge 350. A rotation shaft 251 having a rotor 270 and a bearing 261 at the lower end of the figure is inserted from the other end of the bearing cartridge 350 and is coupled to the upper bearing 261 to rotate the rotor assembly 250a .

The elastic member 141 may be inserted into the bearing support portion 126 of the case body 120 and the lower side of the rotor assembly 250a may be inserted into the bearing support portion 126 of the case body 120 .

The stator 210 may be coupled to an upper end of the rotor assembly 250a.

The reinforcing ribs 352 of the bearing cartridge 350 are respectively inserted into the openings 229 of the slots 228 of the stator core 220 and the upper region of the bearing cartridges 350 is inserted into the openings 229 of the stator 210 And may be inserted into the rotor accommodating space 224.

When the stator 210 is moved downward with respect to the rotor assembly 250a, the stator 210 can be inserted into the case body 120. [

The stator 210 is supported by the stator support portion 134 of the case body 120 and the pole support portion 318 of the bearing cartridge 350 so that the outer rim and the inner flange 227 can be axially supported have.

When the coupling of the stator 210 is completed, the case cover 160 may be coupled to the opening of the case body 120.

The case cover 160 is disposed so that the upper ends of the reinforcing ribs 352 of the rotor assembly 250a correspond to the respective reinforcing rib insertion grooves 179 of the bearing support portion 171 of the case cover 160, The case cover 160 can be coupled to the rotor assembly 250a.

When the upper end of the reinforcing rib 352 is inserted into the corresponding reinforcing rib insertion groove 179, the engaging rib 163 of the case cover 160 can be inserted into the upper opening of the case body 120 .

When the coupling of the case cover 160 is completed, the elastic force of the elastic member 141 of the bearing support portion 126 of the case body 120 may act on the rotor assembly 250a.

Accordingly, a gap (clearance) and / or clearance between the bearings 261 and the rotary shaft 251 can be suppressed.

Thus, vibration and noise generation of the rotating shaft 251 can be suppressed.

In addition, wear of the bearings 261 is suppressed, and the service life can be extended.

[3]

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.

100, 100a: electric motor 110: case
120: Case body 126,171: Bearing support
129, 179: reinforcing rib insertion groove 134: stator support
141: elastic member 160: case cover
210: stator 220: stator core
224: rotor accommodating space 225: yoke portion
226: Paul 227:
228: Slot 229:
230: stator coil 250, 250a: rotor assembly
251: rotating shaft 261: bearing
270: rotor 271: rotor core
281: permanent magnet 285: sleeve
287: End cap
310,320,330,340,350: Bearing cartridge
312: body 314, 314a:
316: bearing insertion portion 318: pole support portion
332, 332a:

Claims (17)

case;
A stator housed inside the case; And
And a rotor assembly rotatably disposed with the gap between the stator and the stator,
Wherein the stator includes a stator core in which a rotor accommodating space for accommodating the rotor is formed,
The stator core includes:
A plurality of pawls projecting toward the rotor;
A slot formed between the pawls and having an opening communicating with the rotor receiving space; And
And a pole piece extending at an end of the pole along the circumferential direction of the rotor accommodating space,
The rotor assembly includes:
A rotating shaft;
A rotor coupled to the rotating shaft;
A bearing disposed on both sides of the rotor to support the rotation shaft; And
And a bearing cartridge provided inside the stator and accommodating the rotor and the bearing therein and aligning the bearing in an axial direction so as to maintain the concentricity,
The bearing cartridge has a plurality of through portions communicating with the inside and outside,
And the plurality of penetrating portions are formed to correspond to the pole pieces. The method according to claim 1,
The bearing cartridge includes: a cylindrical body; And
And a bearing insertion portion formed at both ends of the body. 3. The method of claim 2,
Wherein the through-hole is formed so as to penetrate the circumferential surface so as to communicate with the inside and outside of the body. 3. The method of claim 2,
Wherein the body is formed with a plurality of air vents through a circumferential surface thereof. 3. The method of claim 2,
Wherein the body is provided with a plurality of air holes formed through the circumferential surface so as to be inclined with respect to the axial direction. 3. The method of claim 2,
The case includes: a case body having one side opened; And a case cover coupled to an opening of the case body,
Wherein the case body and the case cover are each provided with a bearing support portion for inserting the bearing insertion portions, respectively. The method according to claim 6,
The stator includes a stator coil wound around the stator core,
Wherein the case body is formed with a stator support portion for supporting the outer periphery of the stator core. 8. The method of claim 7,
Wherein one of the bearings on both sides of the rotor is slidably inserted into the bearing insertion portion. 9. The method of claim 8,
And an elastic member which is brought into contact with a bearing slidably inserted into the bearing insertion portion to apply an elastic force. 8. The method of claim 7,
And the other one of the bearings on both sides of the rotor is press-fitted into the bearing inserting portion. 8. The method of claim 7,
Wherein the bearing cartridge is formed with a pawl support portion for supporting the pawl. delete The method according to claim 6,
Wherein the bearing cartridge has a reinforcing rib projecting radially from the body and inserted into an opening of the slot. 14. The method of claim 13,
Wherein the bearing support portion is provided with a reinforcing rib insertion groove for allowing the reinforcing rib to be inserted therein. The method according to claim 1,
Wherein the bearing cartridge is formed of a synthetic resin member or a ceramic member. 16. The method according to any one of claims 1 to 11 and 13 to 15,
Wherein the rotor has an outer diameter smaller than an outer diameter of the bearing,
A rotor core coupled to the rotating shaft; And
And a permanent magnet coupled to the rotor core. 17. The method of claim 16,
Wherein the permanent magnet is provided on an outer surface of the rotor core,
And a cylindrical sleeve is provided outside the permanent magnet.

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