KR20140087409A - Rotator in motor - Google Patents

Abstract

A rotor of an electric motor according to the present invention includes: a rotor body which rotates around a rotation shaft of the motor; a plurality of buried magnets which are buried in the circumference of the motor shaft of the rotor body; and a plurality of main holes which are formed with a trapezoidal or arc band shape on a part of a body region between the buried magnets and the rotation shaft of the motor. Wherein, the rotor further includes a plurality of semicircular holes which are formed with a long semicircular shape in a circumference direction on a region which is closer to the circumference than the main hole on the region between the main holes.

Description

The rotor of the motor {ROTATOR IN MOTOR}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor structure of a motor, and more particularly to a rotor structure in which a permanent magnet is disposed in a single layer or a multilayer in a rotor to concentrate more magnetic flux density by using a buried permanent magnet, Structure.

An energy conversion device that converts electric energy into mechanical energy such as rotation or linear kinetic energy using an electromagnetic field phenomenon, which is energy in nature, is called an electric motor (hereinafter referred to as "motor").

Various motors have been researched and developed as essential electric devices for obtaining the rotational force. However, according to the tendency of the electric and electronic devices applying and adopting these motors to be small and light in weight, Research on small and lightweight motors that occupy a considerable proportion has been actively pursued. However, the small and light-weighted motor is hard to emit the heat generated from the inside by the rotational motion to the outside.

Fig. 1 shows a conventional permanent magnet buried type rotor according to the prior art. The illustrated permanent magnet buried type rotor has a linear groove 21 having a predetermined length perpendicular to the radial direction from the center of the rotor iron piece 2, Are symmetrically formed.

These straight grooves 21 form a trough in the longitudinal direction of the rotating shaft when the rotor iron piece 2 is stacked. A permanent magnet 30 as shown in FIG. 2 is inserted into the trough to generate a magnetic field. However, in the embedding type having such a structure, there is a problem that a large amount of leakage magnetic flux generated at the end portion of the permanent magnet is generated and the efficiency is lowered, and the rotor body stacked with the iron pieces 2 generates excessive heat during rotation.

An object of the present invention is to provide a motor rotor capable of increasing the output while reducing the weight of the motor.

Another object of the present invention is to provide a motor rotor having a structure capable of efficiently discharging heat generated internally while reducing the weight of the motor.

Alternatively, the present invention intends to provide a design technique capable of achieving an improved output density and a compact and lightweight structure as a high-output high-efficiency motor in motor manufacturing technology.

According to an aspect of the present invention, a rotor for an electric motor includes: a rotor body rotating about a motor rotation axis; A plurality of embedded magnets embedded in a circumferential direction of the rotor main body with respect to the motor rotation axis; And a plurality of main holes in which a part of the body region between the embedded magnets and the motor rotary shaft is formed in a trapezoidal or arc-like strip shape.

The apparatus may further include a plurality of meniscus holes formed in a region between the main holes in a circumferential direction in a region of a circumferential direction than the main hole in a long half-moon shape.

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

Here, the embedded magnets may be rectangular parallelepiped magnets embedded in a region between the main holes and the circumference at a position orthogonal to the radial direction.

Here, the embedded magnets have a rectangular parallelepiped shape in which one end is located in the vicinity of the center of the side of the main hole and the other end is located in the circumferential direction of the region between the main holes, Magnets can be.

Here, the embedded magnets include rectangular parallelepiped magnets embedded in a region between the main holes and the circumference at a position orthogonal to the radial direction, and magnets having one end located near the center of the center of the main hole, , And rectangular parallelepiped magnets whose cross section is arranged in a V-shape in a region between the main holes and the circumference.

The meniscus holes may be formed in the radial direction of the fixing hole to which the means for fixing the stator is connected.

When the rotor for a motor according to the present invention as described above is used, there is an advantage that the magnetic flux density can be increased while reducing the weight of the rotor for the motor.

When the motor is manufactured using the motor rotor having the above-described advantages, the motor can be light-weighted, and the output can be increased.

Alternatively, the rotor for a motor of the present invention is advantageous in that it has a structure capable of efficiently discharging heat generated internally while reducing the weight of the motor.

Alternatively, the rotor for a motor according to the present invention has an advantage that the output density can be increased without increasing the amount of magnet used, thereby reducing the cost.

Alternatively, the rotor for a motor of the present invention has an advantage that heat generation can be effectively suppressed without reducing the outer diameter size of the rotor.

Alternatively, the rotor for a motor of the present invention is advantageous in that it can be made smaller and lighter than the output motor.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view of a rotor iron plate constituting a cross-section of a conventional permanent magnet embedding type rotor. Fig.
2 is a perspective view of a permanent magnet embedded in a buried portion of a permanent magnet.
3 is a cross-sectional plan view showing a rotor for an electric motor according to an embodiment of the present invention.
4 is a cross-sectional plan view showing a rotor for an electric motor according to another embodiment of the present invention.
5 is a pattern showing flux density and magnetic flux distribution in rotating the rotor shown in Fig. 3 relative to the stator.
6 is a pattern showing flux density and magnetic flux distribution during rotation of the rotor shown in Fig. 4 with respect to the stator.
FIG. 7 is a graph showing the torque characteristics of the rotor shown in FIG. 3 and the rotor shown in FIG. 4;
8 is a cross-sectional plan view showing a rotor for an electric motor according to another embodiment of the present invention.
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 main body 122 that rotates about a motor rotation axis; A plurality of embedded magnets 127, 128, 129 embedded in a circumferential direction of the rotor main body 122 with respect to the motor rotation axis; And a plurality of main holes 124 in which part of the body region between the embedded magnets 127, 128, 129 and the motor rotary shaft is formed in a trapezoidal or arc-like strip shape.

The rotor main body 122 is connected to a rotation shaft of the motor, and rotates in an annular space between the motor rotation shaft and an external stator. The rotor main body 122 is formed as one single frame in which embedded slots for embedding the embedded magnets and the holes 124 are formed. However, in the actual manufacturing method, a plurality of pieces of the iron pieces are stacked Shape or a plurality of segments may be assembled.

As shown in the cross section, the plurality of embedded magnets 127, 128, and 129 may have a rectangular parallelepiped magnet shape that is perpendicular to or perpendicular to the radial direction in a region between the main holes and the circumference, And may serve to connect the magnetic flux from the stator.

In the drawing, three embedded magnets 127, 128, and 129 are disposed for one magnetic pole, and are embedded in the region between the main holes 124 and the circumference at a position orthogonal to the radial direction And one end of the rectangular parallelepiped magnet 129 is positioned in the vicinity of the center of the side of the main hole and the other end of the rectangular parallelepiped magnet 129 is located in the circumferential direction of the region between the main holes, Two rectangular parallelepiped plate magnets 127 and 129 may be disposed.

The plate magnets 127, 128, and 129, which are already magnetized permanent magnets, may themselves serve as magnetic flux barriers. However, the magnetic flux lines here must be designed to saturate the magnetically conductive web to restrict the magnetic flux barrier and to be mechanically suitable.

The two V-shaped magnets 127 and 128 having a V-shaped cross section on the rotation axis side of the three embedded magnets are for the main function of the permanent magnet embedded type rotor, It plays the same role as the permanent magnet embedded in the rotor.

The parallel magnet 129 which is a rectangular parallelepiped magnet embedded in a position at a right angle to the radial direction has a magnetic flux which is strengthened by the V-shaped magnets 127 and 128 and the external stator 160, It controls the flow.

In the figure, one main hole 124 is formed in the vicinity of the center axis of one magnetic pole region, in which a part of the rotor main body region is formed in a trapezoidal or arc-like strip shape. The main hole 124 has a main purpose to reduce the weight and / or rotational mass of the rotor and to facilitate the release of heat 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 main body 222 that rotates about a motor rotation axis; A plurality of embedded magnets 227, 228, 229 embedded in a circumferential direction of the rotor main body 222 with respect to the motor rotation axis; And a plurality of main holes 224 in which a part of the body region between the embedded magnets 227, 228, and 229 and the motor rotation shaft is formed in a trapezoidal or arc-like strip shape.

The rotor main body 222 is connected to the rotation shaft of the motor and rotates in an annular space between the motor rotation shaft and an external stator. However, in an actual manufacturing method, a plurality of pieces of iron pieces Or a plurality of segments may be assembled.

As shown in the cross section, the plurality of embedded magnets 227, 228, and 229 may have a rectangular parallelepiped magnet shape perpendicular to or perpendicular to the radial direction in a region between the main holes and the circumference, It is possible to perform the function of continuing the flow of the magnetic flux from the stator.

In the figure, one main hole 224 is formed in the vicinity of the center axis of one magnetic pole region, in which a part of the rotor main body region is formed in a trapezoidal or arc-shaped band shape. The main hole 224 has a main purpose to reduce the weight and / or rotational mass of the rotor and to facilitate the release of heat from the rotor.

In addition, a plurality of half-moon holes 225 formed in a circumferential direction of a long half-moon shape are formed in a region between the main holes 224, that is, on a boundary of a magnetic pole, . At this time, the shape of the meniscus hole 225 is not limited to the crescent shape as shown in FIG. 4, but it can be formed as a crescent shape as well as a crescent shape or a fan shape.

It can be seen that the meniscus holes 225 are formed in 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 a rivet or a screw for coupling the entire rotor, the fixing hole 226 is disposed between the half-hollow holes 225 225) can be configured to perform a part of the role.

The meniscus holes 225 are arranged in the radial direction in such a manner that half of the meniscus holes 225 belong to one magnetic pole region and the other half of the meniscus holes 225 belong to another magnetic pole region. In other embodiments not shown, the meniscus holes may be formed in three or more radial directions of the boundary line between the adjacent two magnetic poles.

The rotor for a motor shown in Fig. 4 is a rotor having a permanent magnet inserted in a rotor and fitted to a shaft to rotate. The rotor is provided with a rectangular shape in which a weight is reduced and a heat radiation area is secured / (Specifically, a trapezoidal or arc-shaped strip), and a crescent-shaped hole in which the path of the magnetic flux is closely formed to increase the concentration of the magnetic flux. That is, a crescent-shaped flux barrier groove is additionally formed in the center of the rotor on the pole boundary of the rotor between adjacent flux barrier portions so that the flow of the magnetic flux generated in the stator is not lost on the polar interface, The leakage of the magnetic flux is prevented, and the output of the motor is improved.

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

As described above, the rotor for a motor of the present invention shown in FIG. 3 and FIG. 4 may include holes formed in a cut-out form in a part of the rotor body. The role of the holes formed in the rotor body is as follows .

When the organic electromotive force is generated in the rotor due to the organic electromotive force generated in the stator, the organic electromotive force is guided in a desired direction by the holes so as not to be interfered with on the pole interface, thereby conserving the organic electromotive force, . Particularly, the flow of magnetic flux around the adjacent pole interface is blocked, and the loss is mainly reduced.

The rotor formed with the meniscus hole makes a smooth flow of the magnetic flux,

When the fixed voltage is applied, the efficiency is better than that of the rotor without the meniscus groove, and the vibration is suppressed more than when the magnetic flux is distributed in a uniform magnetic flux distribution. Further, high torque can be obtained at the same magnetic amount, and energy can be efficiently used.

Next, an experimental result on the effect of using the rotor for a motor according to the present invention will be described.

FIG. 5 shows flux density and magnetic flux distribution in rotating the rotor shown in FIG. 3 with respect to the stator. In the magnetic flux distribution shown in the drawing, it can be seen that the magnetic flux for rotational motion is not weakened by the main hole formed in the rotor. That is, it can be seen that the formation of the main hole effectively dissipates heat without affecting the output of the motor, and the weight of the rotor can be reduced.

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

In addition, when we look at the weight change of the rotor, the weight was 13.87kg when there were no holes. It was reduced to 11.19kg by forming the main hole, and it was again reduced to 11.05 by forming the half-hole.

7 is a graph showing torque characteristics of the rotor shown in Fig. 3 and the rotor shown in Fig. As shown in the figure, the torque characteristic of the rotor of Fig. 3 is 140.81 Nm, the torque characteristic of the rotor of Fig. 4 is 140.87 Nm, and the torque characteristic of the rotor of Fig. .

Table 1 below shows a comparative example having a circular hole as the main hole in the rotor body, an embodiment of FIG. 3 with a trapezoidal main hole, and an embodiment of FIG. 4 with a trapezoidal main hole and a half- To compare the torque at an angle.

In Table 1, considerable improvement was achieved from the torque of 138.2 Nm to 140.81 Nm in the embodiment of FIG. 3 with the trapezoidal main hole than the comparative example with only the circular main hole, and the trapezoidal main hole and the half- It can be seen that in the embodiment of FIG. 4, the torque is again increased to 140.87 Nm to add some improvement.

Fig. 8 is a view similar to Fig. 4 but showing a rotor for a motor according to another embodiment of the present invention in which the magnet for one magnetic pole is provided with only one plate magnet whose cross section is perpendicular to the radius of the rotation axis.

9 is similar to the structure of FIG. 4 except that the magnet for one magnetic pole is located near the center of the center of the main hole and the other end is located on the circumferential side of the area between the main holes, Fig. 3 shows a rotor for a motor according to another embodiment of the present invention in which two plate magnets are arranged in a V-shape in cross section.

In the case of the motor rotor shown in Figs. 8 and 9, only the constitution of the embedded magnets is different, and the other constituent elements and their functions are similar to those of the embodiment shown in Fig. Particularly, the function and effect of the trapezoidal main hole and the half-sphere hole according to the present invention are more so, and a detailed description thereof will be omitted.

It should be noted that the above-described embodiments are intended to be illustrative, not limiting. In addition, it will be understood by those of ordinary skill in the art that various embodiments are possible within the scope of the technical idea of the present invention.

120, 220: Rotor for electric motors
122, 222: rotor body
127, 128, 129, 227, 228, 229: embedded magnets
124, 224: main hole
225: Banwol Hall
226: Fixing hole

Claims (7)

Rotor body rotating around the motor rotation axis
A plurality of embedded magnets embedded in a circumferential direction of the rotor main body with respect to the motor rotation axis; And
And a plurality of main holes formed in a part of the body region between the embedded magnets and the motor rotary shaft in a trapezoidal or arc-
And a rotor for rotating the electric motor.
The method according to claim 1,
And a plurality of half-round holes formed in a region between the main holes in a circumferential direction,
Further comprising:
3. The method of claim 2,
Wherein the meniscus holes are formed in at least one of a crescent shape, a half moon shape, and a fan shape.
The method according to claim 1,
The above-
Wherein the rectangular parallelepiped magnets are embedded in a region between the main hole and the circumference at a position orthogonal to the radial direction.
The method according to claim 1,
The above-
Wherein one end is located in the vicinity of the center of the side of the main hole and the other end is located in the circumferential direction of the region between the main holes and the cross section of which is a V- .
The method according to claim 1,
The above-
A rectangular parallelepiped magnet embedded in a region between the main hole and the circumference at a position perpendicular to the radial direction,
Wherein one end is located in the vicinity of the center of the side of the main hole and the other end is located in the circumferential direction of the region between the main holes and the cross section of which is a V- .
The method according to claim 6,
Wherein the meniscus holes are formed in the radial direction of the fixing hole to which the means for fixing the stator is connected.

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