KR101195221B1 - Iron core of motor with iron loss decreased by magnetic domain refinement and processing method thereof - Google Patents

Abstract

The present invention relates to an iron core of a motor using a non-oriented electrical steel sheet and a processing method thereof, and more particularly, to an iron core of a low iron loss motor by micronization that forms a compression residual stress by making a groove in the iron core of the motor, and a processing method thereof. The purpose is to provide.

The present invention is formed on the iron core of the motor consisting of a tooth formed of a predetermined interval on the outer circumferential surface and a slot is formed between the tooth and the tooth and the one side is open, and the yoke portion connected to the outside of the tooth In the one or two selected from the tooth and the yoke portion, a groove in the vertical direction of the magnetic flux path is formed to form a compression residual stress. A method of processing a steel core of a motor by punching a steel plate, the method comprising: a slitting step of cutting a coilless non-oriented electrical steel sheet to a predetermined size; Before or after punching into a predetermined shape, the micronizing step of forming a compressive residual stress by making a groove in the vertical direction of the magnetic flux path by a thermal or mechanical method at one or two places selected from the teeth and the yoke; The present invention relates to a method for processing an iron core of a motor for reducing iron loss, characterized in that each sheet is processed in an order of a lamination step of laminating the same without rotation.

In the present invention, in manufacturing the iron core of the motor using a non-oriented electrical steel sheet, by forming a compressive residual stress on the surface perpendicular to the magnetic flux path by the thermal or mechanical method before or after the punching to minimize the magnetic flux density reduction This gives the effect of being improved.

Motor, iron core, non-directional, electrical steel, fine-grained, punching, yoke, teeth

Description

IRON CORE OF MOTOR WITH IRON LOSS DECREASED BY MAGNETIC DOMAIN REFINEMENT AND PROCESSING METHOD THEREOF}

The present invention relates to an iron core of a motor made of non-oriented electrical steel sheet and a processing method thereof, and more particularly, to an iron core of a motor having reduced iron loss by magnetic domain micronization treatment and a processing method thereof.

A grain-oriented electrical steel sheet is used as an iron core material of electrical equipment such as transformers, and a steel sheet having magnetic properties with low iron loss and high magnetic flux density is required to reduce power loss and increase efficiency of electrical equipment. In general, a grain-oriented electrical steel sheet refers to a material having an aggregate structure (also called a 'goth aggregate structure') in which the (110) [001] direction is oriented in the rolling direction through hot rolling and cold rolling and annealing processes. In such a grain-oriented electrical steel sheet, the (110) [001] direction is a direction in which magnetization of iron is easy, and the higher the degree of orientation thereof, the better the magnetic characteristics.

As a method for improving the magnetic properties of a grain-oriented electrical steel sheet, as described in Japanese Patent Application Laid-open No. Hei 5-302122, the thickness of the steel sheet is reduced, or B, Se, etc., as a component disclosed in Japanese Patent Laid-Open Publication No. Hei 1-283324. The various elements may be added, or the magnetic domain may be made fine by thermal or mechanical methods, as disclosed in Japanese Patent Application Laid-Open No. 2000-109961 and Korean Patent Application Laid-open No. 2002-63515.

Magnetic micronization technology is known to reduce the iron loss by irradiating the surface of the steel sheet in the direction perpendicular to the rolling direction by a laser (laser), plasma jet or a mechanical method or by scratching to make the magnetic domain finer. Japanese Patent Publication No. 58-26405 and US Pat. No. 4,034,84, etc. are described in the method of miniaturizing magnetic domains using the method. The method of miniaturizing the magnetic domains using a plasma jet is disclosed in Japanese Patent Publication No. 62-96617. The mechanical method is described in Japanese Patent Laid-Open No. 58-5968.

On the other hand, a motor made of non-oriented electrical steel sheet is applied to the electromagnetic induction phenomenon in which the electromagnetic force is generated in a direction perpendicular to the magnetic field by placing the conductor at a right angle in the magnetic field. The motor 20 has a stator assembly fixed in a cylindrical shape inside the frame and wound around a coil 22 as shown in FIG. 1, and a force acting on the rotor surface by being located inside or outside the stator assembly. It can be divided into a rotor assembly that transmits power while rotating by.

Among these, the iron core 1 of the stator assembly which is widely used in industrial and high speed electric motors has a semi-closed slot shape as shown in FIG. 2. That is, the slot 5 into which the stator coil is inserted from the iron core 1 to the inner diameter side of the yoke portion 2 is formed, where each slot 5 is a semi-closed type with a part open.

The non-oriented electrical steel sheet used as the iron core of the motor is provided to the consumer after forming an insulating film on the surface to suppress eddy current generation and minimize power loss. The coil-oriented non-oriented electrical steel sheet provided to the consumer is punched into a predetermined shape by a mold or the like after the slitting continuous operation, and then laminated and used.

This is because the magnetic micronization technology is limited to oriented electrical steel sheet, and the magnetic flux path inside the iron core of the motor is different because the shape of the iron core of the motor varies according to the motor manufacturer. This is because it is difficult.

The present invention has been made to solve the above problems, in the iron core of the motor using a non-oriented electrical steel sheet and a processing method thereof, low iron loss due to the finer magnetic domain to form a groove in the iron core of the motor to form a compression residual stress The purpose is to provide an iron core of the motor and its processing method.

The present invention is formed by protruding teeth of a predetermined interval on the outer circumferential surface and a tooth formed of a slot having a structure in which one side is opened between the tooth and the tooth, and a motor composed of a yoke portion connected to the outside of the tooth and formed in a cylindrical shape In the iron core, the iron core of the motor is reduced by the magnetic domain miniaturization, characterized in that the grooves in one or two selected from the tooth and yoke portion in the vertical direction of the magnetic flux path to form a compression residual stress do.

In addition, the present invention is a method of processing the iron core of the motor by punching the non-oriented electrical steel sheet, the slitting step of cutting the non-oriented electrical steel sheet in a coil size to a predetermined size; Before or after punching into a predetermined shape, the micronizing step of forming a compressive residual stress by making a groove in the vertical direction of the magnetic flux path by a thermal or mechanical method at one or two places selected from the teeth and the yoke; Provided is a method for processing an iron core of a motor for reducing iron loss, characterized in that the processing is performed in the order of lamination steps in which each sheet is laminated identically without rotation.

In addition, the magnetic domain micronizing step of the present invention is the iron core of the motor to reduce the iron loss, characterized in that the groove is formed in the circumferential direction of the iron core in the tooth portion, in the yoke portion in the center direction of the motor to form a compression residual stress Provide processing method.

In addition, the thermal or mechanical method of the magnetic domain micronizing step of the present invention provides a method for processing the iron core of the motor to reduce the iron loss, characterized in that the compressive residual stress is formed by a ball scratch, laser, plasma method.

In the present invention, in manufacturing the iron core of the motor by using a non-oriented electrical steel sheet, by forming a residual stress on the surface perpendicular to the magnetic flux path by the thermal or mechanical method before or after the punching to minimize the magnetic flux density while reducing the iron loss Provides an improved effect.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration of the present invention.

3 is a cross-sectional view of a motor iron core subjected to magnetic domain micronization according to the present invention, FIG. 4 is a flow chart of a method for machining the iron core of a motor according to the present invention, and FIG. 5 is a schematic diagram of magnetic domain micronization prior to punching.

The present invention is a tooth (3) formed by forming a slot (5) having a structure in which one side is opened between the teeth (4) and teeth (4) are formed to protrude at a predetermined interval on the outer peripheral surface, In the iron core of the motor which is connected to the outside of the tooth portion 3 and composed of a yoke portion 2 made of a cylindrical shape, the magnetic flux path 6 is selected at one or two positions selected from the tooth portion 3 and the yoke portion 2. It provides the iron core of the motor which reduced the iron loss by miniaturization of magnetic domains, characterized in that the grooves in the vertical direction to form a compression residual stress.

As shown in Fig. 3, the magnetic flux path 6 at the iron core of the motor is in the center direction of the motor in the tooth part 3 and in the circumferential direction in the yoke part 2, and the present invention is the tooth part 3 and the yoke. The microspheres 7 are formed by forming grooves in the vertical direction of the magnetic flux path 6 by thermal or mechanical methods at one or two locations selected from the section 2 to form a compressive residual stress. In other words, the teeth 3 are subjected to the micronization 7 process in the circumferential direction of the iron core and the yoke 2 in the direction of the center of the motor. Iron loss is reduced by such micronization.

As shown in the flow chart of Figure 4, the present invention in the method for processing the iron core of the motor by punching the non-oriented electrical steel sheet, the slitting step of cutting the non-oriented electrical steel sheet in a coil size to a certain size (S10) Wow; Before or after punching into a predetermined shape (S20), the micronized step of forming a compression residual stress by making a groove in the vertical direction of the magnetic flux path by a thermal or mechanical method at one or two selected from the teeth and yoke (S30); It provides a method for iron core processing of the motor to reduce the iron loss, characterized in that the processing in the order of the lamination step (S40) for laminating each sheet the same without rotation.

First, the slitting step (S10) is performed, and the non-oriented electrical steel sheet in the coil state, which has undergone hot rolling and cold rolling and annealing, is cut into the required size.

After the slitting step, after the punching step S30 after the micronized step S20 as shown in FIG. 4 (a) or after the punching step S30 as shown in FIG. 4 (b) The self-finishing step (S20).

In the case of Fig. 4 (a), as shown in Fig. 5, the punching position is predetermined in the slitting loop 10 to a predetermined size, and the groove is made in the vertical direction of the magnetic flux path by a thermal or mechanical method and compressed. After the magnetic domain micronizing process for forming the residual stress, the mold is punched into the iron core shape of the motor.

In the case of Fig. 4 (b), the slitting coil is punched into the shape of the iron core of the motor by a mold or the like, and the magnetic micronization treatment is performed to form a compression residual stress by making a groove in the vertical direction of the magnetic flux path by a thermal or mechanical method. Will be

As a result, the magnetic domain spacing is narrowed through the magnetic micronization process, and thus the moving distance of the magnetic wall is shortened during magnetization, so that energy lost by heat is reduced and iron loss is reduced.

After the self-finishing step (S30) is subjected to the stacking step (S40). The lamination may be caulking, interlocking, clips, welding, bolting, and the like, and in order to make the best use of magnetic properties, a lamination-free lamination method is preferable to rotating lamination when laminating single sheets.

In the present invention, the method of forming the compressive residual stress in the non-oriented electrical steel sheet is a method of forming the compressive residual stress in the axial direction by a ball scratch in a conventional oriented electrical steel sheet, and rapid temperature rising and cooling by a laser or plasma jet. Any compressive residual stress formation method generated in the process can be used.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited only to these examples.

To prepare a steel slab containing by weight% C: 0.005%, Si: 2.7%, Mn: 0.15%, Al: 0.5%, S: 0.0015%, P: 0.001%, the balance Fe and other unavoidable impurities, Hot-rolled, hot-rolled sheet annealing, cold-rolled, re-crystallized annealing 0.2 mm thin material to a certain size, then punched and changed the magnetic flux density to 0.1 ~ 0.5, and then subjected to magnetic micronization treatment with laser The improvement rate of iron loss according to the magnetic field is shown in FIG.

As shown in Figure 6, it can be seen that the higher the iron loss improvement rate corresponding to the lower magnetic field of the non-oriented electrical steel sheet, the improvement rate of more than 12% iron loss at 0.1T (Tesla).

1 is a schematic view of a motor made of a conventional non-oriented electrical steel sheet.

2 is a cross-sectional view showing the structure of an iron core of a conventional motor.

3 is a cross-sectional view of a motor iron core subjected to magnetic domain miniaturization according to the present invention.

4 is a flow chart of the iron core processing method of the motor according to the present invention.

Fig. 5 is a schematic diagram of the micronization before punching;

Figure 6 is a graph showing the iron loss rate according to the magnetic field before and after the micronized treatment.

Description of the Related Art [0002]

1. Iron core of motor 2. Yoke part

3. tooth 4. tooth

5. Slot 6. Magnetic flux path

7. Fine Graining 10. Loop

20. Motor 21. Rotating shaft

22. Winding

Claims (4)

To the iron core of the motor consisting of teeth formed by protruding teeth of a predetermined interval on the outer circumferential surface and a slot having a structure in which one side is opened between the teeth and teeth, and a yoke part connected to the outside of the teeth is formed in a cylindrical shape. In The iron core is a non-oriented electrical steel sheet material, Iron core of the motor having reduced iron loss by magnetic domain miniaturization, characterized in that the grooves are formed in one or two places selected from the teeth and the yoke to form a compression residual stress. Teeth formed at regular intervals on the outer circumferential surface and formed with a slot having a structure having one side open between the teeth and teeth, and an iron core of a motor composed of a yoke portion connected to the outside of the teeth and having a cylindrical shape. In the processing method, A slitting step of cutting the coil-oriented non-oriented electrical steel sheet to a predetermined size; Before or after punching into a predetermined shape, the micronizing step of forming a compressive residual stress by making a groove in the vertical direction of the magnetic flux path by a thermal or mechanical method at one or two places selected from the teeth and the yoke; Iron core processing method of reducing the iron loss, characterized in that for processing in the order of the lamination step of laminating each sheet the same without rotation. 3. The method of claim 2, Wherein the micro-magnetizing step is to form a groove in the circumferential direction of the iron core in the tooth portion, the yoke portion in the center direction of the motor to form a compressive residual stress, characterized in that the iron core processing method for reducing the iron loss. The method according to claim 2 or 3, The method of processing the iron core of a motor for reducing iron loss, characterized in that the thermal or mechanical method of the micronized step is formed by compressive residual stress by a ball scratch, laser, or plasma method.

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