JPH1080115A - Rotor of reluctance motor and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor of a reluctance motor which improves the strength to centrifugal force and besides reduces the number of parts as far as possible. SOLUTION: In the rotor 1 of a reluctance motor where a plurality of plates 2 made of electromagnetic steel plates and at the peripheries of which projecting poles 3 and recessed poles 4 are made alternately are stacked and fixed, each plate 2 is equipped with a plurality of slits 5 and 6 arranged in series extending over the adjacent fellow projecting poles 3, a connection 7 made between these fellow plural slits 5 and 6, and a periphery connection 8 made between the periphery end of each projecting pole 3 and the end of each slit 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor for a reluctance motor that rotates synchronously by reluctance torque due to a difference in magnetic resistance between a salient pole and a concave pole, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In general, a reluctance motor includes a stator having a plurality of coils and a rotor arranged in an inner space of the stator, and the outer circumference of the rotor has the same number of poles as the number of coils. A number of salient poles and concave poles are formed alternately. When a three-phase alternating current is applied to the coil, a rotating magnetic field is formed on the stator, and the magnetic flux penetrates the rotor to form a magnetic circuit, which is formed by the difference in magnetic resistance of the gap between the salient pole and the concave pole. Rotate synchronously by reluctance torque.

For example, as an anisotropic rotor of a reluctance motor, there is a rotor in which L-shaped bent iron cores are laminated in parallel with an axis, and each iron core is fixed with bolts.
Then, a rotational force is obtained by utilizing the difference between the magnetic resistance of the convex portion and the magnetic resistance of the concave portion of the rotor. Such a reluctance motor has a drawback that when magnetic flux passes through the rotor, an eddy current is generated to generate Joule heat and motor efficiency is reduced due to eddy current loss.

An example of a reluctance motor rotor that solves this problem is described in Japanese Patent Application Laid-Open No. 2-151249. The rotor of the reluctance motor described in this publication includes a bundle of four wires bent in an L-shape, a cross-shaped retainer for fixing a concave portion between the bundles of four wires, and a bundle of four wires. And a shaft that penetrates the retainer hole.

According to the rotor of the reluctance motor configured as described above, since magnetic flux penetrates in the longitudinal direction of the bundle of four wires, the magnetic resistance in the radial direction of the concave portion is large and the magnetic resistance of the convex portion is small. Also, because multiple wires are bundled,
A rotor having a large magnetic resistance in the axial direction of the shaft can be formed, and eddy current loss can be suppressed. In addition,
During rotation of the rotor, circumferential deformation of the wire caused by inertial force is prevented by pressing.

[0006]

However, in the rotor of the reluctance motor described in the above-mentioned publication, since a bundle of four wires is fixed by a retainer, the difference between the gap between the convex portion and the concave portion with respect to the stator is reduced. If the length of the wire is set to be longer in order to increase the size of the wire, the wire is deformed or damaged by centrifugal force generated by the rotation of the rotor, and the magnetic resistance becomes non-uniform. Further, since the protruding portions are formed by the bundle of wires, the lengths of the wires are not uniform, and the magnetic resistance of the protruding portions becomes non-uniform, which causes a problem that the motor efficiency is reduced. Further, there is a problem that the weight of the entire rotor increases by an amount corresponding to the attachment of the retainer for preventing the wire from being deformed in the circumferential direction, thereby lowering the motor efficiency.

On the other hand, when manufacturing the rotor of the reluctance motor, a step of bundling a large number of wires, a step of bending the bundle of wires into an L shape, a step of holding down the bundle of wires and fixing the bundle of wires A number of complicated steps such as a step of cutting the tip to make the length uniform and a step of filling a filler are required. For this reason, there has been a problem that the manufacturing time increases, the productivity decreases, and the manufacturing cost increases. Further, since the salient poles are formed by bundling the wires, it is difficult to secure the outer shape accuracy of the salient poles, and there is a problem that the product quality is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a rotor for a reluctance motor that has improved strength against centrifugal force, has high accuracy in the outer shape of the salient poles, and has as few components as possible. It is intended to provide. Another object of the present invention is to provide a method of manufacturing a rotor of a reluctance motor that can reduce the number of manufacturing steps as much as possible.

[0009]

In order to achieve the above object, the invention according to claim 1 comprises a plurality of plates formed of an electromagnetic steel sheet and having an outer periphery having alternating convex and concave poles. In the rotor of the laminated reluctance motor, in each of the plates, a plurality of slits arranged in series between adjacent convex poles, a connecting portion formed between the plurality of slits, And an outer peripheral connecting portion formed between an end of each slit and an end of each slit.

According to the first aspect of the present invention, each plate is integrally formed of an electromagnetic steel sheet, and a connecting portion formed between a plurality of slits, an outer peripheral end of each salient pole, and an end of each slit. The strength of the plate is improved by the outer peripheral connecting portion formed between them, and the bending moment due to centrifugal force during rotation of the rotor can be reduced as much as possible. In addition, since each plate is integrally formed of an electromagnetic steel sheet, the outer shape accuracy of the salient pole can be improved as much as possible, and the magnetic resistance of the salient pole can be made uniform. Furthermore, since each plate is integrally formed of an electromagnetic steel plate, the strength of the salient pole in the circumferential direction is secured, and it is not necessary to attach a special reinforcing component.

The invention according to claim 2 provides a first step of pressing a magnetic steel sheet to obtain a plate in which salient poles and concave poles are alternately formed on an outer periphery; A plurality of slits arranged in series between adjacent salient poles of the plate, a connecting portion arranged between the plurality of slits, an outer peripheral end of each salient pole and a radially outer portion of each slit. A second step of forming an outer peripheral connection portion disposed between the first and second steps; and a third step of laminating a plurality of plates processed in the first and second steps. . Here, the first step and the second step may be performed simultaneously, or one of the steps may be performed first and then the other.

According to the second aspect of the present invention, the rotor can be manufactured only by performing two pressing steps and one laminating step, and the number of manufacturing steps can be reduced as much as possible. Further, since a plate having salient poles and concave poles is formed by pressing the magnetic steel sheet, the machining accuracy of the salient poles is improved, and the product quality of the rotor is improved. Further, since the salient poles and the concave poles are formed by the press working, the shape accuracy of each plate matches.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a rotor for a reluctance motor according to the present invention and a method for manufacturing the same will be described with reference to the accompanying drawings. This reluctance motor is applied to a driving force source of an electric vehicle and the like. FIG. 1 is a perspective view of a rotor 1 of a reluctance motor (not shown) according to one embodiment of the present invention.

The rotor 1 is constructed by laminating and fixing a plurality of plates 2 each having a substantially cross-shaped planar shape. Each plate 2 is integrally formed of a magnetic non-oriented electromagnetic steel plate, for example, a silicon steel plate, and four salient poles 3 and four concave poles 4 are alternately arranged on the outer periphery of each plate 2. An insulating layer (not shown) made of paint, paper, or the like is formed on the surface of each plate 2.

Each plate 2 is formed with a plurality of slits 5 and 6 arranged in series across adjacent salient poles 3. A plurality of slits 5 are formed linearly in the radial direction with respect to the salient pole 3, and a plurality of linear slits 6 are formed between ends of each slit 5. The widths of the slits 5 and 6 are set to be substantially the same, but the width of the slit 5 located at the center is set wider than the widths of the other slits 5.

A connecting portion 7 is formed between the plurality of slits 5, and an outer connecting portion 8 is formed between the outer peripheral end of each salient pole 3 and the end of each slit 5. The slits 5 and 6 are set as narrow as possible and have a strength that can withstand the centrifugal force during rotation. Thus, the slits 5 are distributed at predetermined intervals in the circumferential direction of the plate 2.

Further, the plates 2 are laminated and fixed to each other by a method such as caulking, welding, or an adhesive, and a circular hole 9 is formed at the center of each plate 2. A shaft 10 is inserted into the hole 9 to hold each plate 2. The shaft 10 is provided with a flange (not shown), and the plate 2 located at the end is positioned by abutting the flange.

FIG. 2 is a schematic side view showing an example of a manufacturing process of the rotor 1. A pair of material feed rollers 12 is arranged downstream of the roll of the long electromagnetic steel sheet 11, and a press machine 13 is arranged downstream of the pair of material rollers 12. The press machine 13 includes an upper die 14 and a lower die 15 which can be moved up and down.
6, 17 and 18 are provided. The lower die 15 is provided with dies 19, 20, and 21 corresponding to the punches 16, 17, and 18, respectively.

Next, a method of manufacturing the rotor 1 will be described.
The magnetic steel sheet 11 wound in a roll shape includes a pair of material feeding rollers 1.
2, the paper is sequentially fed to the press machine 13 side. Then, the upper mold 14 descends and the punches 17 and the die 19 form slits 5 and 6 in the electromagnetic steel sheet 11, and
The connecting part 7 and the outer peripheral connecting part 8 are formed (second step). Then, the upper die 14 is raised to transfer the magnetic steel sheet 11, and the upper die 14 is lowered to form the hole 9 by the punch 17 and the die 20. Further, the upper die 14 is raised and the electromagnetic steel sheet 11 is fed forward, and the upper die 14 is lowered to perform an outer shape punching (first step) on the electromagnetic steel sheet 11 by the punch 18 and the die 21, as shown in FIG. One plate 2 is manufactured.

The above second and first steps are repeated to produce a plurality of plates 2 and laminate them as shown in FIG. 4, and fix each plate 2 together by a method such as caulking, welding, or an adhesive. (Third step) The rotor 1 is manufactured by inserting the shaft into the hole 9.

The rotor 1 configured as described above is disposed in an inner section of a stator (not shown). A four-pole coil is wound around the stator, and when a three-phase alternating current is applied to the coil, a rotating magnetic field is formed on the stator, and a magnetic flux A is generated as shown in FIG.
A magnetic circuit is formed penetrating the rotor 1 as shown in FIG. Then, the rotor 1 is rotated synchronously by the reluctance torque due to the difference in magnetic resistance of the gap between the salient pole 3 and the concave pole 4 of each plate 2 and the stator, and outputs torque.

Here, the plate 2 is provided with magnetic anisotropy by the slits 5 and 6, and the magnetic resistance is reduced along the slits 5 and 6. Penetrates to form a magnetic circuit, while the magnetic resistance is increased by air in the direction traversing each of the slits 5 and 6, so that a magnetic flux is not easily formed. Therefore,
A large difference in inductance between the salient pole 3 and the concave pole 4 can be ensured, and a sufficient reluctance torque can be obtained.
Further, since the rotor 1 is formed by laminating a plurality of plates 2, the magnetic resistance in the laminating direction of the plates 2 is large, and generation of eddy current is suppressed.

In this embodiment, each plate 2 is integrally formed of an electromagnetic steel plate, and a connecting portion 7 formed between a plurality of slits 5 and 6; an outer peripheral end of each salient pole 3; The strength of the plate 2 is improved by the outer peripheral connection portion 8 formed between the end portion of the rotor 5 and the bending moment due to the centrifugal force when the rotor 1 rotates. Therefore, the deformation and breakage of the salient poles 3 are prevented, the magnetic resistance can be kept uniform, and good motor efficiency can be obtained. In particular, even when the length of the salient pole 3 in the radial direction is set as long as possible to secure a large gap between the salient pole 3 and the concave pole 4, it is possible to sufficiently withstand the centrifugal force.

Further, since each plate 2 is integrally formed of an electromagnetic steel plate, the external precision of the salient poles 3 can be improved as much as possible, and the magnetic resistance of each salient pole 3 can be made uniform. And stable motor efficiency can be obtained. Furthermore, since each plate 2 is integrally formed of an electromagnetic steel plate, the circumferential strength of the salient pole 3 is improved, and it is not necessary to attach a special reinforcing component, and the number of components can be reduced as much as possible. it can. Therefore, it is possible to reduce the weight of the rotor 1 as much as possible, and it is possible to maintain good motor efficiency.

In the above embodiment, the rotor 1 can be manufactured by two pressing steps and one laminating step, and the number of manufacturing steps can be reduced as much as possible. Therefore, the manufacturing time can be shortened as much as possible, and the productivity can be improved, and the manufacturing cost can be suppressed. Furthermore, convex pole 3 and concave pole 4
Is formed by pressing, so that the processing accuracy can be improved and the product quality of the rotor 1 can be improved.
Further, since the salient poles 3 and the concave poles 4 are formed by press working, the shape accuracy of each plate 2 matches, and the difference in the magnetic resistance in the axial direction of the rotor 1 becomes uniform.

FIG. 5 shows a plate 2 according to another embodiment.
FIG. 2 is a plan view of FIG. The plate 22 is integrally formed of an electromagnetic steel plate, for example, a silicon steel plate, and salient poles 23 and concave poles 24 are alternately arranged on the outer periphery of the plate 22.
An insulating layer (not shown) made of paint, paper, or the like is formed on the surface of the plate 22.

The plate 22 is formed with a plurality of slits 25 and 26 which are arranged in series across adjacent salient poles 23. A plurality of slits 25 are formed substantially linearly in the radial direction with respect to the salient pole 3, and a plurality of linear slits 26 are formed between the ends of each slit 25. In this embodiment, the width of the slit 26 is set to approximately twice the width of the slit 25.

A connecting portion 27 is formed between each slit 25 and each slit 26, and an outer connecting portion 28 is formed between the outer peripheral end of each salient pole 23 and the end of each slit 25. ing. The slits 25 and 26 are set as narrow as possible and have a strength that can withstand the centrifugal force during rotation. In this manner, the connection portions 27 are dispersedly arranged at predetermined intervals in the circumferential direction of the plate 22. In addition, plate 2
At the center of 2, a circular hole 29 is formed.

A plurality of the plates 22 configured as described above are stacked and fixed to one another by a technique such as caulking, welding, or an adhesive, and a shaft is inserted into the hole 29. The rotor using the plate 22 of FIG. 5 is manufactured by the first to third steps used in the embodiment of FIGS. Also, in the rotor using the plate 22 and the method of manufacturing the rotor, the same effects as in the embodiment of FIGS. 1 to 4 can be obtained.

It should be noted that claim 1 or claim 2 of the present invention.
In, a cold-rolled steel sheet can be used in addition to a silicon steel sheet. Further, each plate in claim 1 of the present invention may be manufactured by a processing method such as casting.

[0031]

As described above, according to the first aspect of the present invention,
Each plate is integrally formed of an electromagnetic steel sheet, and a connecting portion formed between a plurality of slits, and an outer peripheral connecting portion formed between an outer peripheral end of each salient pole and an end of each slit. Is improved, the bending moment due to centrifugal force during rotation of the rotor is reduced as much as possible.
Therefore, deformation and breakage of the salient poles are prevented, so that the magnetic resistance can be kept uniform, and good motor efficiency can be obtained.

Further, since each plate is integrally formed of an electromagnetic steel plate, the external accuracy of the salient poles can be improved as much as possible, the magnetic resistance of each salient pole can be made uniform, and a stable Motor efficiency is obtained. Furthermore, since each plate is integrally formed of an electromagnetic steel plate, the strength of the salient pole in the circumferential direction is improved, and it is not necessary to attach a special reinforcing component, and the number of components can be reduced as much as possible. Therefore, it is possible to reduce the weight of the rotor as much as possible, and it is possible to maintain good motor efficiency.

According to the second aspect of the present invention, the rotor can be manufactured only by performing two pressing steps and one laminating step, and the number of manufacturing steps can be reduced as much as possible. Therefore, the manufacturing time can be shortened as much as possible, and the productivity can be improved, and the manufacturing cost can be suppressed. Further, since the convex and concave poles are formed by pressing, the processing accuracy of each plate becomes uniform, and the product quality of the rotor is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a rotor according to an embodiment of the present invention.

FIG. 2 is a side view showing an example of a manufacturing process of the rotor of FIG.

FIG. 3 is a perspective view of a plate used for the rotor of FIG. 1;

FIG. 4 is a perspective view showing a state in which the plates of FIG. 3 are stacked and fixed.

FIG. 5 is a plan view showing another configuration example of the plate used for the rotor of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor 2,22 Plate 3,23 Convex pole 4,24 Concave pole 5,6,25,26 Slit 7,27 Connection part 8,28 Outer periphery connection part 11 Electromagnetic steel plate

Claims (2)

[Claims] 1. A rotor of a reluctance motor formed by laminating a plurality of plates formed of an electromagnetic steel sheet and having alternating convex and concave poles on the outer periphery, wherein each of the plates has a convex pole adjacent thereto. A plurality of slits arranged in series between the plurality of slits, a connecting portion formed between the plurality of slits, and an outer peripheral connecting portion formed between the outer peripheral end of each of the salient poles and the end of each of the slits And a rotor for a reluctance motor. 2. A first step of pressing a magnetic steel sheet to obtain a plate in which salient poles and concave poles are alternately formed on the outer periphery, and pressing the magnetic steel sheet to form adjacent plates of the plate. A plurality of slits arranged in series between the poles, a connection portion disposed between the plurality of slits, and a portion disposed between an outer peripheral end of each of the salient poles and a radially outer end of each of the slits. And a third step of laminating a plurality of plates processed by the first and second steps. Production method.