KR20170045998A - Rotor assembly and motor having the same - Google Patents

Abstract

According to an embodiment, disclosed are a rotor assembly and a motor including the same. The rotor assembly includes a rotor core including a first hole passing through one surface and the other surface thereof, and a first coupling part disposed on at least one of the one and other surfaces; a plurality of magnets disposed on a side surface of the rotor core; and a cover including a first surface that covers the magnets, and a second surface that covers the one and other surfaces of the rotor core, wherein the second surface of the cover includes a second coupling part coupled to the first coupling part.

Description

[0001] The present invention relates to a rotor assembly,

Embodiments disclose a rotor assembly and a motor including the rotor assembly.

The motor generates power by rotating by the interaction between the rotor having the plurality of magnets and the electromagnetic force generated by the coil wound on the stator.

Accordingly, the motor is provided with a shaft rotatably formed, a rotor coupled to the shaft, and a stator fixed to the inside of the housing, the stator being installed with a gap along the circumference of the rotor.

A coil for forming a rotating magnetic field is wound on the stator to induce electrical interaction with the rotor to induce rotation of the rotor. Therefore, when the rotor rotates, the shaft rotates.

The rotor is provided with a plurality of magnets. The rotor is divided into an IPM rotor in which a magnet is inserted and coupled to the inside of the rotor core, and a SPM (Surface Permanent Magnet) rotor to which a magnet is attached on the surface of the rotor core.

In the case of a motor equipped with an SPM rotor, various protector methods (Molding, Can, Tube, etc.) are applied to improve the durability of the magnet assembly due to its structural characteristics.

Among them, the can type is most commonly applied, and serves to protect the rotor by coupling cup-shaped cans to the outer circumferential surface of the rotor up and down, and to prevent the magnet from coming off.

However, in order to assemble the rotor to the inside of the can, an adhesive should be applied to the inside of the can. However, such an adhesive application process has a problem of complicating the process of assembling the rotor. Particularly, it is very difficult to uniformly apply a predetermined amount of the adhesive to the adhesion region between the can and the rotor.

Embodiments provide a rotor assembly and a motor including the same, wherein the can and the rotor core are combined without the use of an adhesive.

The problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned here can be understood by those skilled in the art from the following description.

A rotor assembly according to an embodiment of the present invention includes: a rotor core including a first hole penetrating one surface and the other surface, and a first coupling portion disposed on at least one surface of the one surface and the other surface; A plurality of magnets disposed on a side surface of the rotor core; And a cover including a first surface covering the magnet and a second surface covering one surface and the other surface of the rotor core, wherein the second surface of the cover has a second fastening portion for engaging with the first fastening portion, .

The first fastening portion may be a projection and the second fastening portion may be an insertion hole.

The protrusion may be caulked and coupled when the insertion hole is inserted.

The cover may include a rim connecting the first surface and the second surface, and the rim may protrude axially with respect to the second surface.

The first directional width of the rim may be greater than the first directional thickness of the magnet, and the first direction may be perpendicular to the axial direction.

And a plurality of second holes surrounding the first holes, and the second surface may expose the plurality of second holes.

A motor according to an embodiment of the present invention includes: a housing; A stator disposed in the housing; A rotor assembly disposed in the stator; And a rotating shaft integrally rotating with the rotor assembly, wherein the rotor assembly includes a first hole penetrating one surface and the other surface, and a first coupling portion disposed on at least one surface of the one surface and the other surface; A plurality of magnets disposed on a side surface of the rotor core; And a cover including a first surface covering the magnet and a second surface covering one surface and the other surface of the rotor core, wherein the second surface of the cover has a second fastening portion for engaging with the first fastening portion, .

According to embodiments, there is an advantageous effect of mechanically coupling the can and the rotor core without the use of an adhesive.

The various and advantageous advantages and effects of the present invention are not limited to the above description, and can be more easily understood in the course of describing a specific embodiment of the present invention.

1 is a conceptual diagram of a motor according to an embodiment of the present invention,
Figure 2 is a partially exploded perspective view of the rotor assembly of Figure 1,
FIG. 3 is a plan view of the rotor core of FIG. 1,
Fig. 4 is a sectional view in the AA direction of Fig. 3,
Figure 5 is a top view of the rotor assembly of Figure 1,
6 is a conceptual view for explaining a structure in which the rotor core and the cover are engaged.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the embodiments of the present invention are not intended to be limited to the specific embodiments but include all modifications, equivalents, and alternatives falling within the spirit and scope of the embodiments.

Terms including ordinals, such as first, second, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the embodiments, the second component may be referred to as a first component, and similarly, the first component may also be referred to as a second component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

In the description of the embodiments, in the case where one element is described as being formed "on or under" another element, the upper (upper) or lower (lower) or under are all such that two elements are in direct contact with each other or one or more other elements are indirectly formed between the two elements. Also, when expressed as "on or under", it may include not only an upward direction but also a downward direction with respect to one element.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings, wherein like or corresponding elements are denoted by the same reference numerals, and redundant description thereof will be omitted.

FIG. 1 is a conceptual view of a motor according to an embodiment of the present invention, and FIG. 2 is a partially exploded perspective view of the rotor assembly of FIG. 1.

Referring to FIG. 1, a motor according to an embodiment of the present invention includes a housing 110, a stator 130 disposed in the housing 110, a rotor assembly 120, and a rotating shaft 160.

The housing 110 may receive the stator 130 and the rotor assembly 120. The housing 110 may further include a cooling structure (not shown) so as to easily discharge the internal heat. The cooling structure may be, but not limited to, an air-cooling or water-cooling structure.

The stator 130 is inserted into the inner space of the housing 110. The stator 130 includes a stator core 131 and a coil 132 wound around the stator core 131.

The stator 130 may be manufactured by winding a coil on a stator core 131 integrally connected to each other. Alternatively, the stator 130 may be formed by winding a plurality of divided cores, respectively, and then assembling them to form a circular stator 130.

The stator 130 may implement a three-phase circuit using a bus bar, but is not limited thereto. The bus bars may be electrically connected to the coils 132 wound on the stator 130, respectively, and may include a plurality of terminals connecting the U, V, and W phases. The power terminal of the bus bar may be exposed to the outside and electrically connected to the external power source or the inverter.

The rotor assembly 120 is rotatably disposed relative to the stator 130. The rotor assembly 120 may be disposed within the stator 130, but is not limited thereto. The rotor assembly 120 may include a rotor core 121 and a magnet 122 mounted on an outer circumferential surface of the rotor core 121. The cover 140 can prevent the separation of the magnet 122 and the rotor core 121 by covering the side surface of the rotor core 121. [ The cover 140 may be made of SUS material, but is not limited thereto.

A rotating shaft 160 is coupled to a central portion of the rotor assembly 120. Accordingly, the rotor assembly 120 and the rotary shaft 160 can rotate together. The rotary shaft 160 may be supported by a first bearing 151 disposed on one side and a second bearing 152 disposed on the other side.

A sensing magnet for acquiring positional information of the rotor core 121 may be coupled to the plate or a similar rotor position sensing means may be installed on the upper side of the rotor assembly 120.

The motor according to the embodiment may be an EPS motor used in an electric power steering system. Specifically, an electric power steering apparatus (EPS) can control the inverter to drive the motor in accordance with driving conditions sensed by an electronic control unit (ECU), such as a vehicle speed sensor, a torque angle sensor, and a torque sensor. The motor according to the embodiment can be driven by a three-phase power source applied from an inverter. However, the configuration of the motor according to the embodiment is not limited to this.

Referring to FIG. 2, a plurality of axially extending strips 123 may be disposed on the outer surface of the rotor core 121. The plurality of strips 123 may form a pocket in which the magnet 122 is disposed. The cover 140 is divided into a first cover 140a and a second cover 140b and can be respectively fitted to one side and the other side of the rotor core 121. [

The first cover 140a and the second cover 140b cover the first surface 141 covering the side surface of the rotor core 121 and the first surface 141 covering the side surface F1 or the second surface F2 of the rotor core 121 A second surface 142, and a rim 143 that connects the first surface 141 and the second surface 142. [

The first surface 141 may serve to fix the magnet 122 so that the magnet 122 does not separate from the side surface of the rotor core 121 and the second surface 142 may cover the cover 140) to the rotor core (121).

The first cover 140a and the second cover 140b may be formed symmetrically with respect to each other and coupled to the rotor core 121, but the present invention is not limited thereto. For example, the first cover 140a may cover the side of the rotor core 121 more than the second cover 140b.

Fig. 3 is a plan view of the rotor core of Fig. 1, and Fig. 4 is a cross-sectional view along the A-A direction of Fig.

Referring to FIG. 3, a first hole H1 is formed at the center of the rotor core 121 to receive a rotation shaft. The first hole (H1) extends in the axial direction of the rotor core (121) and penetrates through one surface and the other surface.

The second hole H2 may be arranged to surround the first hole H1. The second hole (H2) may serve to reduce the weight of the rotor core (121) and / or to control the center of gravity. The diameter of the second hole H2 can be appropriately adjusted within a range in which the weight can be reduced.

The rotor core 121 may include a plurality of strips 123 disposed on the outer circumferential surface and extending in the axial direction. The plurality of magnets 122 may be disposed between the plurality of strips 123.

A first fastening part P1 that engages with the cover 140 may be formed on one surface and / or the other surface of the rotor core 121. [ The first fastening portion P1 may be a protruding fastening protrusion. The protrusion can be engaged with the insertion hole formed in the cover 140. Hereinafter, the first fastening portion P1 will be described as a fastening protrusion and the second fastening portion 142a will be described as an insertion hole. However, the configurations of the first fastening portion P1 and the second fastening portion 142a are not limited thereto Do not. For example, the first fastening portion P1 may be a groove and the second fastening portion 142a may be a fastening protrusion. Also, the first fastening portion P1 may be a burr.

A plurality of first fastening portions P1 may be disposed along the first imaginary circle C1. At this time, the first imaginary circle C1 can accommodate the plurality of second holes H2 surrounding the first hole H1. The first fastening portion P1 may be disposed between two adjacent strips 123. [ That is, the first fastening part P1 can be arranged to be shifted from the imaginary line connecting the strip 123 at the center C of the first hole H1. With this configuration, it is possible to disperse the stress that can be applied to the strip 123 at the time of caulking of the first fastening portion P1.

The first mark S1 may be a groove or a projection for fixing the plurality of core plates 121a. Referring to FIG. 4, the rotor core can be manufactured by stacking a plurality of core plates 121a. At this time, each of the core plates 121a may have the first mark S1 by punching. Therefore, the plurality of core plates 121a can be prevented from slipping in the circumferential direction.

However, the present invention is not limited to this, and the first mark S1 may be formed by stacking a plurality of core strips 121a and punching them integrally. The first mark S1 may be a protrusion on one surface F1 of the rotor core 121 and may be a groove on the other surface F2 of the rotor core 121. [ However, the projections may be planarized to be flattened again.

The first fastening portions P1 may protrude in the axial direction on one surface F1 and the other surface F2 of the rotor, respectively. That is, the outermost core plates 121b constituting the one surface F1 and the other surface F2 of the rotor core 121 may have the first fastening portions P1 arranged in opposite directions.

FIG. 5 is a plan view of the rotor assembly of FIG. 1, and FIG. 6 is a conceptual view illustrating a structure in which the rotor core and the cover are engaged.

Referring to FIG. 5, when the cover 140 is coupled to the rotor core 121, the first fastening portion P1 can engage with the second fastening portion 142a of the cover 140. FIG. That is, the fastening protrusion of the rotor core 121 may be exposed to the outside by engaging with the hole of the cover 140. The second surface 142 of the cover may be formed with an opening through which a plurality of second holes H2 can be exposed. However, if desired, the second surface 142 may cover the second hole H2. In this case, it is possible to prevent the noise generated due to the inflow of air into the second hole (H2).

In this case, the cover 140 may be coupled to the rotor core 121 by caulking the first fastening portion P1 as shown in FIG. The method of joining the first fastening portion P1 and the second fastening portion 142a may be variously modified. For example, the first fastening portion P1 and the second fastening portion 142a may be coupled by spin caulking. Alternatively, the rotor core 121 may be formed with grooves, and then the cover 140 may be punched and coupled.

At this time, the rim 143 connecting the first surface 141 and the second surface 142 of the cover 140 may protrude axially with respect to the second surface 142. Therefore, the space C5 can be formed between the magnet 122 and the magnet. According to this configuration, when the magnet 122 protrudes in the axial direction as compared with the rotor core 121 due to the assembly tolerance, the protruded magnet 122 can be received. Therefore, the coupling force between the second surface 142 and the rotor core 121 may not be lowered by the magnet 122. If the magnet 122 is further protruded due to the assembly tolerance, the second surface 142 is pushed by the magnet 122 to fall off from the rotor core 121 when the rim portion 143 is designed to be in close contact with the magnet 122. [ .

The width D2 of the rim portion 143 may be larger than the width D1 of the magnet 122 to accommodate the protruded magnet 122. [ At this time, the width can be defined as a direction perpendicular to the axial direction. If the width of the rim is smaller, there is a problem that the magnet 122 can not be sufficiently accommodated.

110: Housing
120: rotor assembly
130:
140: cover

Claims (10)

A rotor core including a first hole penetrating through one surface and the other surface, and a first coupling portion disposed on at least one surface of the one surface and the other surface;
A plurality of magnets disposed on a side surface of the rotor core; And
And a cover including a first surface covering the magnet and a second surface covering one surface and the other surface of the rotor core,
And a second surface of the cover includes a second fastening portion that engages the first fastening portion.
The method according to claim 1,
Wherein the first fastening portion is a projection and the second fastening portion is an insertion hole.
3. The method of claim 2,
Wherein the protrusion is caulked when the insertion hole is inserted.
The method according to claim 1,
Wherein the cover includes a rim connecting the first surface and the second surface, the rim protruding axially with respect to the second surface.
5. The method of claim 4,
Wherein a first directional width of the rim is greater than a first directional thickness of the magnet and the first direction is a direction perpendicular to the axial direction.
The method according to claim 1,
And a plurality of second holes surrounding the first holes, the second surfaces exposing the plurality of second holes.
housing;
A stator disposed in the housing;
A rotor assembly disposed in the stator; And
And a rotating shaft rotating integrally with the rotor assembly,
The rotor assembly includes:
A rotor core including a first hole penetrating through one surface and the other surface, and a first coupling portion disposed on at least one surface of the one surface and the other surface;
A plurality of magnets disposed on a side surface of the rotor core; And
And a cover including a first surface covering the magnet and a second surface covering one surface and the other surface of the rotor core,
And the second surface of the cover includes a second fastening portion that engages with the first fastening portion.
8. The method of claim 7,
Wherein the first fastening portion is a projection and the second fastening portion is an insertion hole.
9. The method of claim 8,
And the protrusion is caulked in a state where the insertion hole is inserted.
8. The method of claim 7,
Wherein the cover includes a rim portion connecting the first surface and the second surface, and the rim portion protrudes axially with respect to the second surface.

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