KR102654659B1 - Arc type permanent magnet and flux concentrate type rotor having the same - Google Patents

Abstract

A plurality of arc-type permanent magnets are provided in a magnetic flux-concentrating rotor according to an embodiment of the present specification, each of which is arranged to be spaced apart from each other in the circumferential direction of the rotor core, including an inner diameter portion formed with a first curvature; an outer diameter portion formed with a second curvature different from the first curvature; It includes a connecting portion connecting the end of the inner diameter portion to the end of the outer diameter portion, and satisfies at least one of the five equations below.
(1) A=k1*C (k1 is 0.31 to 0.37)
(2) B=k2*A (k2 is 2.9 to 3.75)
(3) B=k3*E (k3 is 1.8 to 2.7)
(4) D=k4*C (k2 is 0.62 to 0.98)
(5) M=(C/D)*A/(CD) (M is 2.5 or more)
In the above equations (1) to (5), A is the thickness of the permanent magnet, B is the width of the permanent magnet, C is the first curvature of the inner diameter portion, D is the second curvature of the outer diameter portion, and E is the magnetization center point.

Description

Arc type permanent magnet and magnetic flux concentration rotor equipped with same {ARC TYPE PERMANENT MAGNET AND FLUX CONCENTRATE TYPE ROTOR HAVING THE SAME}

This specification relates to an arc-type permanent magnet and a magnetic flux-concentrating rotor equipped with the same, and more specifically, to the design of the shape of the arc-type permanent magnet to maximize the performance of the motor.

A motor is a machine that obtains rotational power from electrical energy and includes a stator and a rotor. The rotor is configured to interact electromagnetically with the stator and rotates by the force acting between the magnetic field and the current flowing in the coil.

Motors that use permanent magnets to generate magnetic fields are divided into surface mounted magnet motors and interior permanent magnet motors depending on the combination structure of the permanent magnets installed in the rotor core. .

Here, in the case of a surface-mounted motor, a permanent magnet is attached to the core surface of the rotor, which has relatively low noise and vibration and good rotational power, but when rotating at high speed, the permanent magnet is separated, mechanical rigidity is reduced, and the operating area is diversified. It has the disadvantage of not being easy to control.

In the case of permanent magnet embedded motors, permanent magnets are inserted and fixed through embedded holes penetrating upward and downward into the core, and compared to existing surface-mounted motors, they provide electromagnetic torque and reluctance torque due to the salient pole structure. It has the characteristic of increasing torque and output by adding reluctance torque.

Meanwhile, recently, a Flux Concentrate Type rotor has been developed that further improves motor efficiency by providing greater torque and output than a permanent magnet embedded motor. The magnetic flux-concentrating rotor is also called a spoke type motor.

A magnetic flux-concentrating rotor has a structurally high magnetic flux concentration, so it can generate high torque and high output. It has the advantage of being able to miniaturize the rotor for the same output, so it can be used in washing machines and electric vehicles that require high torque and high output characteristics. It can be applied to drive motors, etc.

In general, a magnetic flux-concentrating rotor includes a permanent magnet of the square bar type arranged radially around a shaft, and a magnet that supports the permanent magnets of the square bar type and forms a path for magnetic flux. A rotor core is provided.

The rotor core may include yokes disposed between the permanent magnets, and a cylindrical base located between the shaft and the permanent magnets and connected to the yokes.

However, when an open slot structure is adopted in a magnetic flux-concentrating rotor using a square bar-type permanent magnet, magnets scatter on the first and second fixing protrusions formed on both edges of the outer end of the outer diameter core. There is a problem in that mechanical rigidity is weak due to the concentrated force.

Additionally, in the case of a magnetic flux-concentrating rotor equipped with a bar-type permanent magnet, there is a limit to increasing the pole arc of the magnet due to the shape of the permanent magnet.

Therefore, a magnetic flux-concentrating rotor equipped with an arc-type permanent magnet that can increase the magnetic pole arc compared to a bar-type permanent magnet at the same rotor size is being developed.

An example of a magnetic flux-concentrating rotor with an arc-type permanent magnet is disclosed in US Patent No. US15/389636 (hereinafter referred to as “prior patent”).

However, in the case of the prior patent, the performance of each design factor of the arc-type permanent magnet for maximizing the performance of the motor is not disclosed at all, and the shape design of the arc-type permanent magnet is not disclosed at all.

Prior patent: US15/389636

The technical problem that this specification aims to solve is to provide an arc-type permanent magnet that can maximize the performance of a magnetic flux-concentrating rotor.

Another technical problem that this specification aims to solve is to provide an arc-type permanent magnet that can effectively increase the back electromotive force compared to the amount of magnet usage in the same rotor size.

Another technical problem that this specification aims to solve is to provide an arc-type permanent magnet that can maximize back electromotive force.

Another technical problem that this specification aims to solve is to provide a magnetic flux-concentrating rotor that increases mechanical rigidity by effectively dispersing the force of magnet scattering while adopting an open slot structure.

The technical problems to be achieved in this specification are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the description below. You will be able to.

The arc-type permanent magnet according to an aspect of the present specification is an arc-type permanent magnet provided in a magnetic flux-concentrating rotor, each of which is spaced apart from one another in the circumferential direction of the rotor core, and has an inner diameter portion formed with a first curvature. ; an outer diameter portion formed with a second curvature different from the first curvature; It includes a connecting portion connecting the end of the inner diameter portion to the end of the outer diameter portion, and satisfies at least one of the five equations below.

(1) A=k1*C (k1 is 0.31 to 0.37)

(2) B=k2*A (k2 is 2.9 to 3.75)

(3) B=k3*E (k3 is 1.8 to 2.7)

(4) D=k4*C (k2 is 0.62 to 0.98)

(5) M=(C/D)*A/(C-D) (M is 2.5 or more)

In the above equations (1) to (5), A is the thickness of the permanent magnet, B is the width of the permanent magnet, C is the first curvature of the inner diameter portion, D is the second curvature of the outer diameter portion, and E is the magnetization center point.

The second curvature of the outer diameter portion is formed to be greater than the first curvature of the inner diameter portion, and the connection portion includes a first straight portion connected to an end of the outer diameter portion and a second straight portion connecting the end of the first straight portion and the end of the inner diameter portion. do.

The magnetic flux-concentrating rotor with arc-type permanent magnets of this configuration further includes a shaft and a rotor core, wherein the rotor core includes an annular ring-shaped inner diameter core having a shaft through hole into which the shaft is inserted, A plurality of outer diameter cores are arranged along the circumferential direction of the inner diameter core on the outer peripheral surface of the inner diameter core and are spaced apart from each other to form permanent magnet insertion portions for accommodating permanent magnets, and an inner diameter core corresponding to each of the outer diameter cores. A plurality of bridges are arranged along the circumferential direction of the core and each includes a bridge connecting the outer core to the inner core, and the outer core has a first incision located at the lower end.

And the arc-type permanent magnet includes a first connection line connecting the center of the inner core to the center of a first straight portion formed at one end of the arc-type permanent magnet, and a first connection line connecting the center of the inner core to the center of the first straight portion formed at one end of the arc-type permanent magnet. It is inserted into the permanent magnet insertion part so that an included angle of 5 to 20 degrees is maintained between the second connecting lines connecting the centers of the first straight portion formed at the other end of the magnet.

According to this specification, by designing an arc-type permanent magnet using five variables (magnet thickness, magnet width, first curvature of the inner diameter, second curvature of the outer diameter, and magnetization center point gap), the back electromotive force compared to the amount of magnet usage is High arc type permanent magnets can be manufactured, and arc type permanent magnets with maximized back electromotive force can be manufactured.

And because the magnetic flux is bent and flows due to the first incision, the leakage path of the magnetic flux is relatively increased, thereby increasing magnetoresistance and reducing the amount of leakage magnetic flux through the bridge.

Therefore, the back electromotive force of the motor can be increased, the performance of the motor can be improved, and the output density of the motor can be increased.

And by optimizing the arrangement angle of the arc-type permanent magnet, the back electromotive force can be further increased.

And since arc-type permanent magnets are used, even if an open slot structure is adopted, the force of magnet scattering is effectively dispersed compared to bar-type permanent magnets, increasing the mechanical rigidity of the rotor core.

The effects that can be obtained in this specification are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. .

The accompanying drawings, which are included as part of the detailed description to aid understanding of the present specification, provide examples of the present specification and explain technical features of the present specification together with the detailed description.
Figure 1 is a cross-sectional view showing an arc-type permanent magnet that maximizes magnet usage based on the optimized size of the arc-type permanent magnet used in a 10-pole motor.
FIG. 2 is a diagram showing an arc-type permanent magnet in which the thickness and magnetization center point gap of the permanent magnet shown in FIG. 1 are changed.
FIG. 3 is a diagram showing an arc-type permanent magnet in which the second curvature of the outer diameter of the permanent magnet shown in FIG. 1 and the gap at the center of magnetization are changed.
FIG. 4 is a diagram showing an arc-type permanent magnet in which the first curvature of the inner diameter of the permanent magnet shown in FIG. 1 and the gap at the center of magnetization are changed.
FIG. 5 is a diagram showing an arc-type permanent magnet in which the width of the permanent magnet shown in FIG. 1, the second curvature of the outer diameter portion, and the gap at the magnetization center point are changed.
FIG. 6 is a diagram showing an arc-type permanent magnet in which the thickness and first curvature of the inner diameter of the permanent magnet shown in FIG. 1 are changed.
Figure 7 is a graph showing the magnitude of back electromotive force compared to the amount of magnet usage according to the ratio of the first curvature of the inner diameter portion and the second curvature of the outer diameter portion of the arc-type permanent magnet.
Figure 8 is a graph showing the magnitude of back electromotive force compared to the amount of magnet usage according to the ratio of the thickness and width of an arc-type permanent magnet.
Figure 9 is a graph showing the magnitude of back electromotive force compared to the amount of magnet usage according to the ratio of the gap and width of the magnetization center point of an arc-type permanent magnet.
Figure 10 is a graph showing the magnitude of back electromotive force compared to the amount of magnet usage according to the ratio of the first curvature and thickness of the inner diameter of an arc-type permanent magnet.
Figure 11 is a graph showing the magnitude of back electromotive force according to the first curvature of the inner diameter portion, the second curvature of the outer diameter portion, and thickness of an arc-type permanent magnet.
Figure 12 is a diagram showing the schematic configuration of a magnetic flux-concentrating rotor equipped with an arc-type permanent magnet and a motor equipped with this rotor according to an embodiment of the present specification.
FIG. 13 is a diagram showing the schematic configuration of the rotor core shown in FIG. 12.
FIG. 14 is a diagram for explaining the leakage magnetic flux occurring in the magnetic flux-concentrating rotor shown in FIG. 12.
Figure 15 is a diagram showing the schematic configuration of a rotor core provided in a magnetic flux-concentrating rotor according to the second embodiment of the present specification.
Figure 16 is a diagram showing the schematic configuration of a rotor core provided in a magnetic flux-concentrating rotor according to the third embodiment of the present specification.
Figure 17 is a diagram showing the schematic configuration of a rotor core provided in a magnetic flux-concentrating rotor according to the fourth embodiment of the present specification.
Figure 18 is a graph showing the improvement rate of back electromotive force according to the arrangement angle of the arc-type permanent magnet.

Hereinafter, embodiments disclosed in the present specification will be described in detail with reference to the attached drawings. However, identical or similar components will be assigned the same reference numbers regardless of reference numerals, and duplicate descriptions thereof will be omitted.

The suffixes “assembly” and “part” for components used in the following description are given or used interchangeably only considering the ease of preparing the specification, and do not have distinct meanings or roles in themselves.

Additionally, in describing the embodiments disclosed in this specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in this specification, the detailed descriptions will be omitted.

In addition, the attached drawings are only for easy understanding of the embodiments disclosed in this specification, and the technical idea disclosed in this specification is not limited by the attached drawings, and all changes included in the spirit and technical scope of this specification are not limited. , should be understood to include equivalents or substitutes.

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

When a component is said to be "coupled to" or "in contact with" another component, it may be directly coupled to or in direct contact with that other component, but there may also be other components in between. It must be understood that there is.

On the other hand, when a component is said to be “directly coupled” or “in direct contact” with another component, it should be understood that there are no other components in between.

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

In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, preferred embodiments according to the present specification will be described in detail with reference to the attached drawings. However, identical or similar components will be assigned the same reference numbers regardless of the reference numerals, and duplicate descriptions thereof will be omitted.

Figure 1 is a cross-sectional view showing an arc-type permanent magnet that maximizes magnet usage based on the optimized size of the arc-type permanent magnet used in a 10-pole motor.

2 to 6 are diagrams showing arc-type permanent magnets according to embodiments in which at least two of the five design elements are changed.

First, referring to FIG. 1, the permanent magnet 230 is an arc-type magnet having an inner diameter portion 231 formed with a first curvature (C) and an outer diameter portion 233 formed with a second curvature (D). It is a permanent magnet.

In this specification, the second curvature (D) of the outer diameter portion (233) and the first curvature (C) of the inner diameter portion (231) are different from each other.

That is, the second curvature (D) of the outer diameter portion (233) may be greater than the first curvature (C) of the inner diameter portion (231), and the first curvature (C) of the inner diameter portion (231) may be greater than the first curvature (C) of the outer diameter portion (233). It may be greater than the second curvature of .

The permanent magnet 230 further includes a connecting portion 235 connecting the end of the inner diameter portion 231 and the end of the outer diameter portion 233, and the connecting portion 235 is connected to the end of the outer diameter portion 233. It includes a straight portion 235a and a second straight portion 235b connecting the end of the first straight portion 235a and the end of the inner diameter portion 231.

And the first straight portion 235a and the second straight portion 235b may be formed to have an interior angle A1 of 90 degrees.

1 shows an arc type in which the first curvature (C) of the inner diameter portion 231 is R12.5, the second curvature (D) of the outer diameter portion 233 is R8.0, and the magnetization center point gap (E) is 10.0. A permanent magnet 230 is shown.

Here, the magnetization center point gap (E) refers to the distance between the center point of the first curvature (C) and the center point of the second curvature (D).

And the arc-type permanent magnet 230 shown in FIG. 1 has a thickness (A) of 5.5 and a width (B) of 15.1.

FIG. 2 is a diagram showing an arc-type permanent magnet in which the thickness and magnetization center point gap of the permanent magnet shown in FIG. 1 are changed.

In the arc-type permanent magnet of this embodiment, the remaining design factors excluding the thickness (A) and the magnetization center point gap (E), that is, the width (B), the first curvature (C) of the inner diameter portion, and the second curvature of the outer diameter portion ( D) has the same value as the permanent magnet in Figure 1.

The thickness (A) of the arc-type permanent magnet shown in Figure 2 is 4.5, and the magnetization center point gap (E) is 9.

FIG. 3 is a diagram showing an arc-type permanent magnet in which the second curvature of the outer diameter of the permanent magnet shown in FIG. 1 and the gap at the center of magnetization are changed.

In the arc-type permanent magnet of this embodiment, the remaining design factors except the second curvature (D) of the outer diameter portion and the magnetization center point gap (E), that is, the width (B), the first curvature (C) of the inner diameter portion, and the thickness ( A) has the same value as the permanent magnet in Figure 1.

The second curvature (D) of the outer diameter of the arc-type permanent magnet shown in FIG. 3 is R10.0, and the gap at the center of magnetization is 7.

FIG. 4 is a diagram showing an arc-type permanent magnet in which the first curvature of the inner diameter of the permanent magnet shown in FIG. 1 and the gap at the center of magnetization are changed.

In the arc-type permanent magnet of this embodiment, the remaining design factors except the first curvature (C) of the inner diameter portion and the magnetization center point gap (E), that is, the thickness (A) and width (B) and the second curvature of the outer diameter portion ( D) has the same value as the permanent magnet in Figure 1.

The first curvature (C) of the inner diameter of the permanent magnet shown in Figure 4 is R10.5, and the magnetization center point gap (E) is 5.

FIG. 5 is a diagram showing an arc-type permanent magnet in which the width of the permanent magnet shown in FIG. 1, the second curvature of the outer diameter portion, and the gap at the magnetization center point are changed.

In the arc-type permanent magnet of this embodiment, the remaining design factors excluding the width (B), the second curvature (D) of the outer diameter portion, and the magnetization center point gap (E), that is, the thickness (A) and the first curvature of the inner diameter portion ( C) has the same value as the permanent magnet in Figure 1.

The width (B) of the arc-type permanent magnet shown in FIG. 5 is 13, the second curvature (D) of the outer diameter portion is R14.0, and the magnetization center point gap (E) is 3.

FIG. 6 is a diagram showing an arc-type permanent magnet in which the thickness and first curvature of the inner diameter of the permanent magnet shown in FIG. 1 are changed.

In the arc-type permanent magnet of this embodiment, the remaining design factors except the thickness (A) and the first curvature (C) of the inner diameter portion, that is, the width (B), the second curvature (D) of the outer diameter portion, and the magnetization center point gap ( E) has the same value as the permanent magnet in Figure 1.

The thickness (A) of the arc-type permanent magnet shown in FIG. 6 is 4, the first curvature (C) of the inner diameter is R13, and the magnetization center point gap (E) is 7.

Table 1 below lists the magnet usage, back electromotive force (Bemf), and back electromotive force compared to the magnet usage for each permanent magnet shown in FIGS. 1 to 6.

Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 magnet usage 128% 100% 109% 114% 102% 96% back electromotive force 55.8 50.9 56.1 57.1 51.7 52.8 Back electromotive force/magnet usage 0.436 0.502 0.503 0.494 0.500 0.543

Referring to Table 1 above, there are five design factors, namely, thickness (A), width (B), first curvature of the inner diameter (C), second curvature of the outer diameter (D), and magnetization center point gap (E). It is possible to optimize the performance required for the motor by appropriately changing .

As an example, in the case of an air conditioner motor that requires a magnetic overhang to maintain the sensor spacing, it is preferable to use the permanent magnet shown in FIG. 4.

In addition, it is preferable to use the permanent magnet shown in FIG. 6 as a permanent magnet that has a large effect of increasing back electromotive force compared to the amount of magnet used.

For square bar type permanent magnets, the width and thickness of the permanent magnet are used as design factors.

However, it is difficult to diversify the shape design of the permanent magnet with the above two design factors, and when the outer diameter of the shaft is determined according to the application product group, the range is further limited.

Additionally, in the case of a square bar type permanent magnet, the thickness of the permanent magnet is highly correlated with the demagnetization resistance of the motor, and the length of the permanent magnet contributes more to improving the back electromotive force of the motor.

However, in a magnetic flux-concentrating rotor, the longer the length of the permanent magnet, the deeper the lower end of the permanent magnet is located toward the inner core, which causes the problem that the magnetizing properties of the permanent magnet are lowered.

However, in the case of the arc-type permanent magnet of this specification, when it has the same magnet volume as the square bar type, it is possible to design the length of the permanent magnet (width of the permanent magnet) to be short, and the thickness of both ends of the permanent magnet is also Since it is possible to design it thinly, it is advantageous compared to bar-type permanent magnets in terms of magnetization.

In addition, according to the present specification, the effect of increasing the back electromotive force of the motor according to the five design factors (thickness, width, first curvature of the inner diameter part, second curvature of the outer diameter part, and magnetization center point gap) defined in this specification is analyzed. It is possible to maximize the effect of the motor by specifying the ratio of each factor.

Hereinafter, the effect of increasing back electromotive force compared to magnet usage according to the ratio of each factor will be described with reference to FIGS. 7 to 10.

Figure 7 is a graph showing the magnitude of back electromotive force compared to the amount of magnet usage according to the ratio of the first curvature of the inner diameter part and the second curvature of the outer diameter part of the arc-type permanent magnet, and Figure 8 is the ratio of the thickness and width of the arc-type permanent magnet. This is a graph showing the magnitude of back electromotive force compared to the amount of magnet usage.

And Figure 9 is a graph showing the magnitude of back electromotive force compared to the amount of magnet usage according to the ratio of the gap and width of the magnetization center point of the arc-type permanent magnet, and Figure 10 is a graph showing the ratio of the first curvature and thickness of the inner diameter of the arc-type permanent magnet. This is a graph showing the size of back electromotive force compared to the amount of magnet usage.

Referring to FIGS. 7 to 10, an arc-type permanent magnet can be designed to satisfy at least one of equations (1) to (4) below.

(1) A=k1*C (k1 is 0.31 to 0.37)

(2) B=k2*A (k2 is 2.9 to 3.75)

(3) B=k3*E (k3 is 1.8 to 2.7)

(4) D=k4*C (k2 is 0.62 to 0.98)

In the above equations (1) to (4), the units of the thickness (A), width (B), and magnetization center point gap (E) of the permanent magnet may be the same.

As an example, the units of thickness (A), width (B), and magnetization center point gap (E) of the permanent magnet may be mm or cm.

In the above equations (1) to (4), if k1 to k4 satisfy the above values, the back electromotive force (back electromotive force/magnet usage) compared to the magnet usage of the permanent magnet is approximately 0.5 or more.

On the other hand, if you want to design a motor with excellent back electromotive force rather than excellent back electromotive force performance compared to the amount of magnet usage, you can refer to equation (5) below.

(5) M=(C/D)*A/(C-D) (M is 2.5 or more)

Referring to FIG. 11, it can be seen that the back electromotive force rises rapidly as the design variable “M” exceeds 2, and then the slope becomes gentle.

Therefore, when designing a permanent magnet that maximizes back electromotive force, it is desirable to set the design variable “M” to 2.5 or more.

According to the above description, it is possible to design a permanent magnet to satisfy at least one of the above equations (1) to (5), depending on the required performance or conditions of the motor.

Hereinafter, a magnetic flux-concentrating rotor equipped with an arc-type permanent magnet according to the present specification and a 10-pole motor equipped with this rotor will be described.

It is a diagram showing the schematic configuration of a magnetic flux-concentrating rotor equipped with an arc-type permanent magnet and a 10-pole motor equipped with this rotor, and FIG. 13 is a diagram showing the schematic configuration of the rotor core shown in FIG. 12. 14 is a diagram to explain the leakage magnetic flux occurring in the magnetic flux-concentrating rotor shown in FIG. 12.

A motor equipped with a magnetic flux-concentrating rotor according to the first embodiment of the present specification includes a stator 100 and a magnetic flux-concentrating rotor 200.

The stator 100 may include a stator core 110 and a plurality of teeth 120 protruding from the stator core 110 in the radial direction. The stator core 110 may be formed in a ring shape.

A pole shoe 130 extending on both sides in the circumferential direction may be provided at the radial inner end of the tooth 120. A slot 140 is formed between the teeth. Accordingly, the coil 150 is wound through the teeth 120 and the slot 140.

The magnetic flux-concentrating rotor 200 includes a shaft 210, a rotor core 220, and a permanent magnet 230.

As shown in FIG. 1, the permanent magnet 230 is an arc-type magnet having an inner diameter portion 231 formed with a first curvature (C) and an outer diameter portion 233 formed with a second curvature (D). It is a permanent magnet.

The second curvature (D) of the outer diameter portion (233) is formed in a different size from the first curvature (C) of the inner diameter portion (231), and the second curvature (D) of the outer diameter portion (233) is formed in different sizes from the first curvature (C) of the inner diameter portion (231). ) may be formed to be larger than the first curvature (C), or conversely, may be formed to be smaller.

The magnetization direction of each permanent magnet 230 proceeds in the tangential direction (T), and the outer diameter portion 233 is formed as a strong magnetic flux surface, and the inner diameter portion 231 is formed as a weak magnetic flux surface.

The permanent magnet 230 may further include a connecting portion 235 connecting the end of the inner diameter portion 231 and the end of the outer diameter portion 233, and the connecting portion 235 is connected to the end of the outer diameter portion 233. It may include a first straight portion 235a and a second straight portion 235b connecting the end of the first straight portion 235a and the end of the inner diameter portion 231.

And the first straight portion 235a and the second straight portion 235b may be formed to have an interior angle A1 of 90 degrees.

The rotor core 220 includes an inner core 221, an outer core 223, and a bridge 225.

The inner diameter core 221 is formed in an annular ring shape with a shaft through hole 221a into which the shaft 210 is inserted.

The outer core 223 is arranged in plural pieces along the circumferential direction (or tangential direction) of the inner diameter core 221 on the outer peripheral surface of the inner diameter core 221, and is a permanent magnet for accommodating the arc-type permanent magnet 230. They are arranged to be spaced apart from each other to form magnet insertion portions 223a.

A first fixing protrusion 223b and a second fixing protrusion 223c protruding in an arc direction may be formed on both edges of the outer end of the outer diameter core 223. The first and second fixing protrusions (223b) (223c) fix the position of the permanent magnet 230 when the arc-type permanent magnet 230 is inserted into the permanent magnet insertion portion 223a, and the rotor ( It serves to prevent the permanent magnet 230 from scattering when the 200) rotates.

That is, the outer diameter core 223 has an open slot structure.

A plurality of bridges 225 are arranged along the circumferential direction of the inner core 221, corresponding to each of the outer cores 223, and connect each of the outer cores 223 to the inner core 221.

The outer core 223 may be referred to as an outer core, and the inner core 221 may be referred to as an inner core. This is because the inner diameter core 221 is located radially inside the outer diameter core 223. Also, the outer diameter core 223 may be referred to as a yoke.

In the permanent magnet insertion portion 223a, arc-type permanent magnets 230 having an inner diameter portion 231 with a weak magnetic flux surface and an outer diameter portion 233 with a strong magnetic flux surface are oriented with different sides from those adjacent to each other. It is placed. Therefore, magnetic flux can be compensated and torque ripple can be reduced.

At the lower end of the arc-type permanent magnet 230, that is, between the first straight portion 235a of the permanent magnet 230 and the inner core 221, there are two bridges adjacent to each other in the circumferential direction of the inner core 221. A gap H1 partitioned by (225) is formed.

The outer diameter core 223 has a first side 223d in contact with the inner diameter 231 of the first permanent magnet 230A among the two adjacent permanent magnets, and a second permanent magnet among the two permanent magnets ( It has a second side 223e in contact with the outer diameter portion 233 of 230B) and further includes a first cut portion 223f located at the lower end.

The first cut portion 223f is formed by extending from an end of the second side 223e of the outer diameter core 223 toward the first side 223d.

And the bridge 225 extends from the end of the first side 223d of the outer diameter core 223 and has a first side 225a connected to the inner diameter core 221, and on the opposite side of the first side 225a. It is located and includes a second side 225b connected to the inner core 221.

The second side 225b of the bridge 225 is positioned spaced apart from the end of the outer diameter portion 233 of the second permanent magnet 230B toward the first side 223d of the outer diameter core 223.

Here, the lower end of the second permanent magnet 230B may be the first straight portion 235a.

The separation distance D1 of the second side 225b of the bridge 225 may be set to various values.

According to this configuration, a portion of the first side 225a of the bridge 225 may contact at least a portion of the connection portion 235 of the first permanent magnet 230A, for example, the second straight portion 235b. there is.

The first cut portion 223f is formed at the outer diameter portion from the point P1 where the first straight portion 235a of the arc-type permanent magnet 230 and the lower end of the second side 223e of the outer diameter core 223 are connected. It may extend toward the first side 223d of the core 223.

As shown in the embodiments of FIGS. 12 to 14, the first cut portion 223f is formed by forming the first straight portion 235a of the arc-type permanent magnet 230 and the second side of the outer diameter core 223 ( It extends from the point P1 where the lower end of 223e) is connected toward the first side 223d of the outer diameter core 223, and includes at least a portion of the connection portion 235 of the arc-type permanent magnet 230, for example, It may extend parallel to the first straight portion 235a.

And the second side 225b of the bridge 225 extends from the end of the first cut 223f and is connected to the inner cervical core 221.

The separation distance D1 of the second side 225b of the bridge 225 may be shorter than the length L3 of the first cutout 223f.

In addition, the portion P2 where the second side 225b of the bridge 225 and the end of the first cutout 223f are connected is radially outer than the first straight portion 235a of the permanent magnet 230. can be located

Additionally, the maximum width W1 of the bridge 225 is smaller than the width W2 of the lower end of the outer core 223.

In order to effectively reduce the amount of leakage magnetic flux, it is preferable that the first cutout 223f and the second side 225b of the bridge 225 form a right angle or an acute angle A2.

12 to 14, the first cut 223f and the second side 225b of the bridge 225 form an acute angle.

According to this configuration, as shown in FIG. 14, the second side 225b of the bridge 225 is connected to the second permanent magnet ( It is located away from the outer diameter portion 233 of 230B) toward the first side 223d of the outer diameter core 223.

Therefore, compared to the magnetic flux-concentrating rotor without the first cutout, the leakage path is relatively increased, thereby increasing the magnetic resistance, and the magnetic flux is bent and flows due to the first cutout (223f), so leakage through the bridge 225 The magnetic flux decreases.

And since arc-type permanent magnets are used, magnetic flux and efficiency are increased compared to bar-type permanent magnets, and even if an open slot structure is adopted, the force of magnet scattering is effectively dispersed compared to bar-type permanent magnets, increasing the mechanical rigidity of the rotor core. This increases.

Hereinafter, a rotor core provided in a magnetic flux-concentrating rotor according to another embodiment of the present specification will be described.

In describing the following embodiment, the same reference numerals are assigned to the same components as those of the above-described first embodiment, and detailed description thereof is omitted.

Figure 15 is a diagram showing the schematic configuration of a rotor core provided in a magnetic flux-concentrating rotor according to the second embodiment of the present specification.

In the embodiment shown in FIG. 15, the first cut portion 223f is formed by bending toward the inner diameter core 221 compared to the first embodiment described above.

That is, in the above-described first embodiment, the first cut portion 223f extends from the first straight portion 235a of the permanent magnet 230, and includes at least a portion of the connection portion 235 of the permanent magnet 230, e.g. For example, a configuration extending parallel to the first straight portion 235a is adopted.

However, as in the present embodiment, the first cut portion 223f may be formed by bending toward the inner core 221 compared to the first embodiment described above.

And, in the case of this embodiment, the angle A2 between the first cutout 223f and the second side 225b of the bridge 225 forms approximately a right angle.

According to the present inventor's experiments, in order to effectively improve the back electromotive force, it is desirable to increase the leakage path, so the angle A2 formed by the first cutout 223f and the second side 225b of the bridge 225 is It was found that it is preferable to form it small.

Figure 16 is a diagram showing the schematic configuration of a rotor core provided in a magnetic flux-concentrating rotor according to the third embodiment of the present specification.

The outer diameter core provided in the magnetic flux-concentrating rotor of this embodiment is at least a portion of the connection portion 235 of the permanent magnet 230, for example, the first cut portion 223f extending parallel to the first straight portion 235a. ) further includes a second cut portion 223g extending radially outward from the end of the bridge 225, and the second side 225b of the bridge 225 extends from the end of the second cut portion 223g to form an inner cervical core ( 221).

And the angle A2 between the second cutout 223g and the second side 225b of the bridge 225 forms an acute angle, and the second cutout 223g and the second side 225b of the bridge 225 form an acute angle. ) The portion (P3) to which the end is connected is located radially outward from the first straight portion (235a) of the permanent magnet 230.

Therefore, the magnetic flux concentration type rotor of this embodiment has a relatively increased leakage path compared to the first and second embodiments of the present specification, and thus the back electromotive force can be greatly improved.

Figure 17 is a diagram showing the schematic configuration of a rotor core provided in a magnetic flux-concentrating rotor according to the fourth embodiment of the present specification.

The rotor core provided in the magnetic flux-concentrating rotor of this embodiment forms a hole 223h in the outer core 223 of the rotor core of the first embodiment described above, thereby generating local saturation at the lower end of the outer diameter core 223. Shiki's configuration is starting.

In order to effectively generate local saturation on the leakage path of the outer diameter core 223, the gap D2 between the first side 223d of the outer diameter core 223 and the hole 223h is maintained at about 0.5 mm. It is desirable.

Meanwhile, the hole 223h can also be applied to the outer diameter core provided in other embodiments described above.

In the case of a magnetic flux-concentrating rotor with arc-type permanent magnets, the shape design of the permanent magnet is important, but how the permanent magnet is placed in the rotor core is also an important design factor.

Figure 18 is a graph showing the improvement rate of back electromotive force according to the arrangement angle of the arc-type permanent magnet.

12 and 18, in the case of a 10-pole motor, the arc-type permanent magnet 230 has an angle A3 of 5 to 20 degrees between the first connection line (L4) and the second connection line (L5). It can be seen that the improvement rate of back electromotive force is excellent when inserted into the permanent magnet insertion part so that it is maintained.

Here, the first connection line (L4) refers to a line connecting the center of the inner diameter core 221 to the center of the first straight portion 235a formed at one end of the arc-type permanent magnet 230, and the second The connection line L5 refers to a line connecting the center of the inner core 221 to the center of the first straight portion 235a formed at the other end of the arc-type permanent magnet 230.

It is obvious to those skilled in the art that the present specification can be embodied in other specific forms without departing from the essential features of the present specification. Accordingly, the above detailed description should not be construed as restrictive in all respects and should be considered illustrative. The scope of this specification should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of this specification are included in the scope of this specification.

100: Stator 200: Magnetic flux-concentrating rotor
210: shaft 220: rotor core
221: inner core 223: outer core
225: Bridge 230: Arc type permanent magnet

Claims (24)

delete delete delete shaft;
rotor core; and
Multiple arc-type permanent magnets
Including,
Each of the plurality of arc-type permanent magnets includes,
an inner diameter portion formed with a first curvature;
an outer diameter portion formed with a second curvature greater than the first curvature;
A connecting portion connecting an end of the inner diameter portion to an end of the outer diameter portion and including a first straight portion connected to the end of the outer diameter portion, and a second straight portion connecting the end of the first straight portion and the end of the inner diameter portion.
Includes,
Satisfies at least one of the five formulas below,
(1) A/C=k1 (k1 is 0.31 to 0.37)
(2) B/A=k2 (k2 is 2.9 to 3.75)
(3) B/E=k3 (k3 is 1.8 to 2.7)
(4) D/C=k4 (k4 is 0.62 to 0.98)
(5) M=(C/D)*A/(CD) (M is 2.5 or more)
The rotor core is,
an annular ring-shaped inner diameter core having a shaft through hole into which the shaft is inserted;
A plurality of outer-diameter cores are arranged along the circumferential direction of the inner-diameter core on the outer peripheral surface of the inner-diameter core and are spaced apart from each other to form permanent magnet insertion portions for accommodating the permanent magnets;
A plurality of bridges are arranged along the circumferential direction of the inner diameter core, corresponding to each of the outer diameter cores, and connecting each of the outer diameter cores to the inner diameter core.
Includes,
The outer cervical core has a first incision located at the lower end,
The outer diameter core includes a first side that contacts the inner diameter of a first permanent magnet among two adjacent permanent magnets, and an outer diameter portion of a second permanent magnet located on the opposite side of the first side of the two permanent magnets. It has a second side in contact with,
The first incision is formed extending from an end of the second side of the outer diameter core toward the first side,
In the above equations (1) to (5),
A magnetic flux-concentrating rotor where A is the thickness of the permanent magnet, B is the width of the permanent magnet, C is the first curvature of the inner diameter, D is the second curvature of the outer diameter, and E is the magnetization center point gap. In paragraph 4,
A magnetic flux-concentrating rotor in which 10 arc-type permanent magnets are embedded in the rotor core. In paragraph 5,
The permanent magnet includes a first connection line connecting the center of the inner diameter core to the center of a first straight portion formed at one end of the permanent magnet, and a first connection line formed at the other end of the permanent magnet from the center of the inner diameter core. A magnetic flux-concentrating rotor inserted into the permanent magnet insertion section so that an included angle of 5 to 20 degrees is maintained between the second connection lines connecting the centers of the straight sections. delete In any one of paragraphs 4 to 6,
The bridge has a first side extending from an end of the first side of the outer diameter core and connected to the inner diameter core, and a second side located on the opposite side of the first side of the bridge and connected to the inner diameter core. A flux-concentrating rotor comprising: In paragraph 8:
A magnetic flux concentration type rotor wherein the second side of the bridge is positioned spaced apart from an end of the outer diameter portion of the second permanent magnet toward the first side of the outer diameter core. In paragraph 9:
A magnetic flux-concentrating rotor in which a portion of the first side of the bridge is in contact with at least a portion of the connection portion of the first permanent magnet. In paragraph 10:
The first cut portion extends toward the first side of the outer diameter core from a point where the first straight portion of the permanent magnet and the lower end of the second side of the outer diameter core are connected. In paragraph 11:
A magnetic flux-concentrating rotor wherein the second side of the bridge extends from an end of the first cutout and is connected to the inner core. In paragraph 12:
A magnetic flux-concentrating rotor wherein the portion where the second side of the bridge and the end of the first cutout are connected is located radially outward from the first straight portion of the first permanent magnet. In paragraph 12:
A magnetic flux-concentrating rotor wherein the first cut portion and the second side of the bridge form an acute angle. In paragraph 12:
A magnetic flux-concentrating rotor wherein the first cut portion is parallel to at least a portion of the connection portion of the permanent magnet. In paragraph 11:
The outer diameter core further includes a second cutout extending radially outward from an end of the first cutout. In paragraph 16:
A magnetic flux-concentrating rotor wherein the second side of the bridge extends from an end of the second cutout and is connected to the inner core. In paragraph 17:
A magnetic flux-concentrating rotor wherein the portion where the second side of the bridge and the end of the second cutout are connected is located radially outward from the first straight portion of the first permanent magnet. In paragraph 17:
A magnetic flux-concentrating rotor wherein the second cut portion and the second side of the bridge form an acute angle. In paragraph 17:
A magnetic flux-concentrating rotor wherein the first cut portion is formed parallel to at least a portion of the connection portion of the permanent magnet. delete delete delete delete

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