WO2014104820A1

WO2014104820A1 - Rotor for motor

Info

Publication number: WO2014104820A1
Application number: PCT/KR2013/012318
Authority: WO
Inventors: 정영호; 이정호
Original assignee: 주식회사 효성
Priority date: 2012-12-28
Filing date: 2013-12-27
Publication date: 2014-07-03
Also published as: KR20140087409A; KR101426168B1

Abstract

According to the present invention, a rotor for an electric motor may comprise: a rotor body rotating about a motor rotating shaft; multiple embedded magnets embedded in the circumferential side of the rotor body, which is relative to the motor rotating shaft; and multiple main holes formed into a trapezoid or an arc-shaped band in one portion of a main region between the embedded magnets and the motor rotating shaft. The rotor may further comprise multiple crescent-shaped holes formed in a region between the main holes such that the crescent-shaped holes are formed in a circumferential direction in the region closer to the circumference than the main holes.

Description

Rotor of motor

The present invention relates to a rotor structure of a motor, and in particular, a rotor capable of effectively dissipating heat while concentrating more magnetic flux density by using a permanent magnet embedded by placing a permanent magnet in a single layer or multiple layers inside the rotor. It's about structure.

An energy converter that converts electrical energy into mechanical energy such as rotational or linear kinetic energy by using an electric field phenomenon, which is energy existing in nature, is called an electric motor (hereinafter referred to as a "motor").

Motors are an essential electric device for obtaining rotational force, and various motors have been researched and developed. However, according to the propensity of research on small and light-weighted electric and electronic devices applying and adopting these motors, compared to the overall volume and weight Small and light researches on motors, which take up a considerable portion of the weight, have been actively promoted. By the way, the compact, lightweight motor is inevitably added to the difficulty of dissipating heat generated inside by the rotational movement to the outside.

Figure 1 shows a conventional permanent magnet buried type rotor in the prior art, the permanent magnet buried type rotor shown is a straight portion groove 21 of a predetermined length at a right angle to the radial direction from the center of the rotor iron piece (2) Form symmetrically.

These straight part grooves 21 form a trough in the longitudinal direction of the rotating shaft when the rotor iron pieces 2 are stacked. The magnetic field is generated by inserting the permanent magnet 30 as shown in FIG. However, the buried type of the structure has a problem that the efficiency is lowered by a large amount of leakage magnetic flux generated at the end of the permanent magnet and excessive heat is generated when the rotor body laminated with the iron pieces (2) is rotated.

The present invention is to provide a rotor for a motor that can increase the power while reducing the weight of the motor.

Another object of the present invention is to provide a rotor for a motor having a structure capable of effectively dissipating heat generated from the inside to the outside while reducing the weight of the motor.

Another object of the present invention is to provide a design technology capable of achieving an output density improvement and a compact and lightweight structure as a high output high efficiency motor in a motor manufacturing technology.

Rotor for an electric motor according to the spirit of the present invention, the rotor body for rotating around the motor axis of rotation; A plurality of embedding magnets embedded in the circumferential side of the rotor body of the rotor body; And a plurality of main holes in which a part of the main body region between the embedded magnets and the motor rotation shaft is formed in a trapezoidal or arc-shaped band shape.

Here, the plurality of half moon holes may be further formed in a region between the main holes in a circumferential direction that is longer in the circumferential direction than the main hole.

Here, the half moon holes may be formed in at least one of a crescent shape, a half moon shape, a fan shape.

Here, the embedded magnets may be rectangular parallelepiped magnets embedded in a position perpendicular to the radial direction in an area between the main hole and the circumference.

Here, the embedded magnets, one end is located near the center of the side of the main hole and the other end is located on the circumferential side of the region between the main holes, the rectangular parallelepiped whose cross section is arranged in a V-shape in the region between the main hole and the circumference Magnets.

Here, the buried magnets are rectangular magnets embedded in the radially orthogonal position in the area between the main hole and the circumference, and one end is located near the center of the side of the main hole and the other end is the circumference of the area between the main holes. Located in the side, the cross-section in the region between the main hole and the circumference may be rectangular parallelepiped magnets arranged in a V-shape.

Here, the half moon holes may be formed before and after the radial direction of the fixing hole to which the means for fixing the stator is connected.

By implementing the motor rotor of the present invention according to the above configuration, there is an advantage that can increase the magnetic flux density while reducing the motor rotor.

If the motor is manufactured by the rotor for the motor of the above-described advantages, it is possible to cause the advantage of increasing the power while reducing the motor weight.

Alternatively, the rotor for a motor of the present invention has the advantage of having a structure capable of effectively dissipating heat generated from the inside to the outside while reducing the weight of the motor.

Alternatively, the rotor for a motor of the present invention can increase the power density without increasing the amount of magnets used, thereby reducing the cost.

Alternatively, the motor rotor of the present invention has the advantage of being able to effectively suppress heat generation without reducing the outer diameter size of the rotor.

Alternatively, the rotor for a motor of the present invention has an advantage of enabling a smaller and lighter weight than an output motor.

1 is a plan view of a rotor iron plate forming a cross section of a rotor of a conventional permanent magnet buried type.

2 is a perspective view of a permanent magnet embedded in a buried portion of the permanent magnet.

3 is a cross-sectional plan view showing a rotor for an electric motor according to an embodiment of the present invention.

Figure 4 is a cross-sectional plan view showing a rotor for an electric motor according to another embodiment of the present invention.

FIG. 5 is a pattern showing flux density and flux distribution while rotating the rotor shown in FIG. 3 with respect to a stator. FIG.

FIG. 6 is a pattern showing flux density and flux distribution while rotating the rotor shown in FIG. 4 with respect to a stator. FIG.

7 is a graph showing torque characteristics of the rotor shown in FIG. 3 and the rotor shown in FIG. 4.

Figure 8 is a cross-sectional plan view showing a rotor for an electric motor according to another embodiment of the present invention.

Figure 9 is a cross-sectional plan view showing a rotor for an electric motor according to another embodiment of the present invention.

The rotor 120 for an electric motor according to an embodiment of the present invention as shown in FIG. 3 includes: a rotor body 122 rotating around a motor rotation axis; A plurality of embedding magnets (127, 128, 129) embedded in the circumferential side of the rotor body 122 of the rotor body 122; And a plurality of main holes 124 in which a part of the main body region between the buried

magnets

127, 128, 129 and the motor rotation shaft is formed in a trapezoidal or arc-shaped band shape.

The rotor body 122 is connected to the rotation shaft of the motor, and rotates in an annular space between the motor rotation shaft and the external stator. When the rotor body 122 is viewed as a whole, the rotor body 122 forms a single frame in which the embedding slots and the holes 124 are formed, but in the actual manufacturing method, a plurality of pieces of iron are stacked. Form or a plurality of segments may have an assembled form.

The plurality of buried

magnets

127, 128, and 129 may have a rectangular plank plank shape perpendicular to or near perpendicular to the radial direction in a region between the main holes and the circumference, as shown in cross section. It can play a role to connect the flux of flux from the stator.

In the drawing, three buried

magnets

127, 128, and 129 are disposed for one magnetic pole, and for each magnetic pole, embedded in the area between the main hole 124 and the circumference at a position perpendicular to the radial direction. The rectangular cuboid planks 129 and one end are located near the center of the side of the main hole and the other end is located at the circumferential side of the area between the main holes, and the cross section is arranged in a V shape in the area between the main holes and the circumference. Two

cuboid planks

127 and 129 may be disposed.

The planks (127, 128, 129), which are already magnetized permanent magnets, also serve as magnetic flux barriers, but the magnetic force lines generated here should be designed to be mechanically appropriate while saturating the magnetically conductive web to limit the magnetic flux barrier.

Of the three embedded magnets, two V-

shaped magnets

127 and 128 having a V-shaped cross section on the rotational axis side are for a main function of the permanent magnet-embedded rotor. It plays the same role as the permanent magnet embedded in the rotor.

Parallel magnets 129, which are cuboid planks embedded at a position perpendicular to the radial direction, enhance the magnetic flux by the V-

shaped magnets

127 and 128 and the external stator 160, It is responsible for adjusting the flow.

In the figure, in the region near the central axis of one magnetic pole region, one main hole 124 is formed in which some of the rotor body regions are formed in a trapezoidal or arcuate band shape. The main hole 124 has a main purpose to reduce the weight and / or rotational mass of the rotor, and to facilitate heat dissipation from the rotor.

The rotor 220 for an electric motor according to another embodiment of the present invention as shown in FIG. 4 includes: a rotor body 222 rotating about a motor rotation axis; A plurality of embedded magnets (227, 228, 229) embedded in the circumferential side of the rotor body (222) with respect to the motor axis of rotation; And a plurality of main holes 224 in which a part of the main body region between the buried

magnets

227, 228, and 229 and the motor rotation shaft is formed in a trapezoidal or arc-shaped band shape.

The rotor body 222 is connected to the rotating shaft of the motor, the appearance of a single frame structure that rotates in the annular space between the motor rotation shaft and the external stator, but in the actual manufacturing method in the form of a plurality of stacked pieces Or a plurality of segments may be assembled.

The plurality of buried

magnets

227, 228, and 229 may have a rectangular plank plank shape perpendicular to or near perpendicular to a radial direction in a region between the main holes and the circumference, as shown in cross-section thereof. It is the same as the case of FIG. 3 such that it can play a role for connecting the flow of magnetic flux from the stator.

In the figure, in the region near the central axis of one magnetic pole region, one main hole 224 is formed in which some of the rotor body regions are formed in a trapezoidal or arcuate band shape. The main hole 224 has a main purpose to reduce the weight and / or rotational mass of the rotor, and to facilitate heat dissipation from the rotor.

In addition, on the area between the main holes 224, that is, on the boundary of the magnetic pole, a plurality of half moon holes 225 are formed in the circumferentially longer half moon shape in the circumferential area than the main hole 224. It can be seen that. At this time, the shape of the half moon hole 225 is not limited to the crescent shape as shown in Fig. 4, it can be formed not only crescent shape, but also a half moon shape, a fan shape.

In the figure, it can be seen that the half moon holes 225 are formed before and after the radial direction of the fixing hole 226 to which the means for fixing the rotor 220 is connected. When it is necessary to form a hole 226 for passing through the rivets or screws for coupling the entire rotor, it is arranged between the half moon holes 225, so that the fixing hole 226 is a half moon hole ( 225 may be configured to perform some role.

The half moon holes 225 are arranged in a radial direction in the form of half belonging to one magnetic pole region and the other half belonging to another magnetic pole region at the boundary between two adjacent magnetic poles. In another embodiment, not shown, the half moon holes may be formed in three or more in the radial direction of the boundary between the two adjacent magnetic poles.

The motor rotor shown in FIG. 4 is a rectangular body formed by a permanent magnet inserted into the rotor and fitted with a shaft to rotate to form a light weight on the rotor body and secure heat dissipation area / improved output density. (Specifically, trapezoidal or arc-shaped band-shaped) and a crescent-shaped hole in which a magnetic flux path is formed closely so as to increase the concentration of magnetic flux. That is, a crescent shaped flux barrier groove is additionally formed on the pole boundary of the rotor between the adjacent flux barrier portions so that the flow of magnetic flux generated in the stator is more concentrated on the magnetic path without being lost on the pole boundary. The flow rate of the motor improves the output of the motor by preventing the magnetic flux from leaking.

Here, in adding a rectangular main hole added to facilitate the heat dissipation of the rotational force of the rotor, it is desirable to satisfy the depth of the back iron does not affect the output characteristics of the motor.

As described above, the motor rotor of the present invention shown in FIGS. 3 and 4 may include holes formed in a form in which a part of the rotor body is cut out. The roles of the holes formed in the rotor body are as follows. .

The organic electromotive force generated by the stator causes the organic electromotive force to be induced by the holes in the desired direction so that the organic electromotive force flows in the rotor so that the organic electromotive force is prevented from being lost. . In particular, the flow of magnetic flux around the adjacent pole interface is blocked and mainly losses are reduced.

The rotor in which the half moon-shaped hole is formed creates a smooth flow of magnetic flux.

When a predetermined voltage is applied, it exhibits better efficiency than the rotor without a half moon groove, and exhibits an effect of suppressing vibration more than when the magnetic flux is biased with a uniform magnetic flux distribution. In addition, high torque can be obtained at the same magnetic amount, and energy can be efficiently used.

Next, we will look at the experimental results for the effect of using the rotor for the motor according to the present invention.

FIG. 5 shows the flux density and the flux distribution while rotating the rotor shown in FIG. 3 with respect to the stator. FIG. In the magnetic flux distribution shown, it can be seen that there is no weakening of the magnetic flux for the rotational movement by the main hole formed in the rotor. That is, it can be seen that the formation of the main hole effectively performs heat dissipation without affecting the output of the motor and can reduce the weight of the rotor.

FIG. 6 shows the flux density and the flux distribution while the rotor shown in FIG. 4 is rotated with respect to the stator. Comparing the magnetic flux distribution of FIG. 6 with the magnetic flux distribution of FIG. 5, it can be seen that the leakage magnetic flux generated between the magnetic poles is effectively prevented. In addition, it can be seen that the magnetic flux density of FIG. 5 is 2.873 tesla, whereas the magnetic flux density of FIG. 6 is improved to 2.880 tesla.

In addition, looking at the weight change of the rotor, the weight was 13.87kg when there are no holes, the main hole was formed to reduce the weight to 11.19kg, it can be seen that again achieved the reduction effect to 11.05 by forming a half moon hole.

FIG. 7 is a graph showing torque characteristics of the rotor shown in FIG. 3 and the rotor shown in FIG. 4. As shown, the torque characteristic of the rotor of FIG. 3 is 140.81 Nm, and the torque characteristic of the rotor of FIG. 4 is 140.87 Nm, which is slightly higher but the torque characteristic of the rotor of FIG. It can be seen that.

Table 1 below shows the same speed of the comparative example having a circular hole as a main hole in the rotor body, the embodiment of FIG. 3 with a trapezoidal main hole, and the embodiment of FIG. 4 with a trapezoidal main hole and a half moon hole, and It is for comparing torque at an angle.

Table 1

320 arms	circle		Trapezoid		Trapezoid + crescent
Speed [rpm]	Angle [°]	Torque [Nm]	Angle [°]	Torque [Nm]	Angle [°]	Torque [Nm]
2750	120	138.2	120	140.81	120	140.87

In Table 1 above, in the embodiment of FIG. 3 with a trapezoidal main hole than a comparative example with only a circular main hole, a significant improvement in torque has been achieved, from 138.2 Nm to 140.81 Nm, with a trapezoidal main hole and a half moon hole. It can be seen from the example 4 that the torque has added some improvement again to 140.87 Nm.

FIG. 8 shows a rotor for a motor according to another embodiment of the structure similar to that of FIG. 4, but with only one plank stone whose cross section is perpendicular to the radius of the axis of rotation of the magnet.

In addition, FIG. 9 is similar to the structure of FIG. 4, but includes an embedded magnet for one magnetic pole, one end of which is located near the center of the side of the main hole and the other end of which is located on the circumference side of the area between the main holes, and the area between the main holes and the circumference. Fig. 3 shows a rotor for a motor according to another embodiment of a structure having two planks whose cross sections are arranged in a V shape.

Also in the case of the rotor for the motor shown in Figs. 8 and 9, only the configuration of the embedded magnets differs, and other components and their functions are similar to those of the embodiment shown in Fig. 4 above. Particularly, the functions and effects of the trapezoidal main hole and the half moon hole according to the spirit of the present invention are further increased, and thus, redundant description will be omitted.

It should be noted that the above embodiment is for the purpose of illustration and not for the purpose of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.

The present invention relates to the rotor structure of a motor and can be used in the motor field.

Claims

Rotor body rotating around the motor shaft

A plurality of embedding magnets embedded in the circumferential side of the rotor body of the rotor body; And

A plurality of main holes in which a part of the main body region between the buried magnets and the motor shaft is formed in a trapezoidal or arc-shaped band shape;

Rotor for electric motor comprising a.
The method of claim 1,

A plurality of half moon holes are formed in the region between the main holes in the circumferential direction longer in the circumferential direction than the main hole in the region between the main holes

The rotor for an electric motor further comprising.
The method of claim 2,

The half moon holes are a rotor for an electric motor formed in at least one of a crescent shape, a half moon shape, a fan shape.
The method of claim 1,

The embedding magnets,

And a rectangular parallelepiped magnet embedded in a radially orthogonal position in an area between each main hole and the circumference.
The method of claim 1,

The embedding magnets,

Rotor for electric motor, one end of which is located near the center of the side of the main hole and the other end is located on the circumferential side of the region between the main holes, and the rectangular magnets whose cross sections are arranged in a V-shape in the region between the main holes and the circumference. .
The method of claim 1,

The embedding magnets,

Rectangular parallelepiped magnets embedded in radial and perpendicular positions in an area between the main hole and the circumference;

Rotor for electric motor, one end of which is located near the center of the side of the main hole and the other end is located on the circumferential side of the region between the main holes, and the rectangular magnets whose cross sections are arranged in a V-shape in the region between the main holes and the circumference. .
The method of claim 6,

And the half moon holes are formed before and after the radial direction of the fixing hole to which the means for fixing the stator is connected.