JPS59117450A - Permanent magnet rotor and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a product of high reliability by alternately bonding or welding members of short rectangular shape of substantially sector shape in section of permanent magnets and nonmagnetic units on the outer periphery of a core of cylindrical shape which forms a rotor, thereby deleting the number of manufacturing steps. CONSTITUTION:A rotor core 1 is formed of a magnetic material such as a soft steel material or the like. A through hole 2' is formed at the center, and a shaft 2 is engaged in the hole. A plurality of plates 4 of the same size of nonmagnetic material of short rectangular shape in a sector-shaped section formed, for example, of stainless steel (18Cr-18Mn) are secured with an adhesive or by welding at an equal pitch on the circumferential surface 3. A permanent magnet 5 formed of a magnet material having high energy product of a short rectangular shape substantially in a sector-shaped section is secured between the plates 4. In this manner, the leakage of a magnetic flux 6 is reduced to enhance the efficiency and the manufacture is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a permanent magnet rotor used in a rotating electric machine and a method for manufacturing the same.

[Technical background of the invention]

Permanent magnet rotors used in rotating electric machines such as small synchronous motors are generally manufactured by the following procedure. First, a disk-shaped yoke in which a plurality of recesses in which permanent magnets are to be housed are formed along the outer periphery is manufactured from a steel sheet material by means such as press working. A rotor core is formed by laminating a plurality of yokes of the same shape, and permanent magnets are accommodated in each accommodation groove formed in the axial direction on the outer circumferential surface of the rotor core by meeting the recesses of each of the yokes. Then, it is fixed in the housing groove with adhesive or the like.

[Problems with background technology]

However, the above manufacturing method and the permanent magnet rotor manufactured by this manufacturing method have the following problems. In other words, in the above manufacturing method, a steel plate material is punched into a complicated-shaped yoke by pressing or the like, and a plurality of the above yokes are further laminated to form the rotor core. The number of man-hours is large9, and as a result, the manufacturing time is long and the manufacturing cost is increased, leading to problems of increasing the manufacturing cost. Furthermore, there was also the problem that a cutting die had to be manufactured separately in order to carry out the press working.

Next, in the permanent magnet rotor manufactured by the manufacturing method described above, each permanent magnet is housed in each accommodation groove formed on the outer peripheral surface of the rotor core, so that there is no space between adjacent permanent magnets. A yoke made of magnetic material is then used. For this reason, leakage magnetic flux that passes through the yoke occurs between the permanent magnets, and the magnetic flux that passes through the stator side is reduced, resulting in a low utilization efficiency of the magnetic flux of the permanent magnets.As a result, this permanent magnet rotor There was a problem in that the performance of motors etc. using this was relatively poor.

[Purpose of the invention]

The present invention has been made based on the above circumstances, and its purpose is to reduce the number of manufacturing steps, reduce manufacturing costs, and reduce magnetic flux leakage between permanent magnets. It is an object of the present invention to provide a permanent magnet rotor and a method for manufacturing the same, which can reduce the amount of damage caused by the rotor and improve the performance of a motor incorporating the rotor.

[Summary of the invention]

In order to achieve the above object, in the permanent magnet rotor and the manufacturing method thereof of the present invention, a plurality of permanent magnets and a plurality of non-magnetic materials are alternately attached on the outer peripheral surface of a rotating body along the circumferential direction. The feature is that it is made to look like this.

Furthermore, each permanent magnet and a cladding tube, in which the part that contacts each permanent magnet attached to the outer circumferential surface of the rotating body is formed of a magnetic material, and the part that contacts each non-magnetic body are formed of a non-magnetic material, are attached to each of the permanent magnets and It is characterized in that it is fitted and fixed to one outer circumferential surface formed by each of the permanent magnets and each non-magnetic material so as to commonly cover each non-magnetic material.

[Embodiments of the invention]

A permanent magnet rotor and a method for manufacturing the same according to an embodiment of the present invention will be described below with reference to a sectional view of the permanent magnet rotor shown in FIG.

In the figure, 1 is a rotor core formed in a cylindrical shape. This rotor core 1 is made of a magnetic material such as mild steel, and a rotating shaft 2 is inserted into a through hole provided at the axial center position. Fixed through. Four rectangular non-magnetic plates 4 made of, for example, stainless steel (18Cr-18Mn) and having a substantially fan-shaped cross section are distributed on the outer circumferential surface 3 of the rotor core 1, and an adhesive (for example, Sumitomo 3M) Fix it with Scotchweld structural adhesive 2214) manufactured by Co., Ltd. Next, four permanent magnet plates 5 formed in a rectangular shape like the non-magnetic plates 4 are attached to the outer peripheral surface of the rotor core 1 with the above-mentioned adhesive between the non-magnetic plates 4. Glue and fix. The permanent magnet plate 5 is, for example, a rare earth cobalt magnet Toslex (
The rotor is made of a magnetic material with a high energy product, such as those manufactured by Tokyo Shibaura Electric Co., Ltd., and by using this magnetic material in the rotor, it is possible to obtain a small, lightweight, and high-output motor. . For example, by using a permanent magnet plate with a thickness of 10 to 12 mm, an output of several tens of kW can be obtained. Note that, before each non-magnetic plate 4 and each permanent magnet plate 5 are adhesively fixed to the outer circumferential surface of the rotor core 1, the mutual adhesive surfaces are roughly ground with a sander or the like to increase the adhesive surface area.

With the above manufacturing method, the rotor core 1, each non-magnetic plate 4, and each permanent magnet plate 5 are each formed into a predetermined shape in advance, and only these are bonded with adhesive. In addition, the shapes of the rotor core 1, nonmagnetic plate 4, and permanent magnet plate 5 are simple. Therefore, compared to the conventional manufacturing method, in which a yoke with a recessed portion for accommodating a permanent magnet was manufactured by press working, and the yoke had to be layered, the number of manufacturing steps and manufacturing time was reduced. This can be significantly reduced, and as a result, manufacturing costs can be reduced.

In the permanent magnet rotor manufactured by the above manufacturing method, the magnetic flux 6 formed by each permanent magnet plate 5 is transferred from the permanent magnet plate 5 to the rotor and the stator (not shown), as shown by the arrows in the figure. After passing through the magnetic path on the stator side (not shown) through the gap between them, the magnet passes through the gap again, enters the adjacent permanent magnet plate 5, and then passes through the inside of the rotor core 1. Return to the original permanent magnet plate 5. In such a magnetic circuit, since the non-magnetic plate 4 is interposed between the adjacent permanent magnet plates 5, leakage magnetic flux generated between the permanent magnet plates 5 and passing through the non-magnetic plate 4 is reduced. The occurrence can be significantly suppressed. Therefore, the magnetic flux density of the magnetic flux 6 passing through the stator side can be increased, and as a result, the efficiency of the motor using the permanent magnet rotor of this embodiment can be improved compared to that of the conventional permanent magnet rotor. This can be significantly improved compared to the previous case.

Note that the method for manufacturing a permanent magnet rotor according to the present invention is not limited to the above-described embodiments. In the embodiment, a non-magnetic plate 4 formed in a predetermined shape is attached to the rotor core 1.
For example, using a non-magnetic material such as stainless steel (18Cr-18Mn) and a metal that can be melt-plated, this metal can be attached to the non-magnetic surface 3 of the outer circumferential surface 3. After melting and depositing the part where the body is to be placed, the melted and deposited nonmagnetic material may be formed into a predetermined shape using the aforementioned sander or the like. According to such a manufacturing method, the accommodation grooves for accommodating each permanent magnet can be formed only by cutting the melt-plated non-magnetic material, so it is possible to obtain the same effect as the above-mentioned embodiment. be.

FIG. 2(,) is a sectional view showing a schematic configuration of a permanent magnet rotor according to another embodiment of the present invention, and the same parts as in FIG. 1 are given the same reference numerals. Therefore, the explanation of the overlapping parts will be omitted.

In this embodiment, a cladding tube 7 that commonly covers each non-magnetic plate 4 and each permanent magnet plate 5 fixed to the outer circumferential surface 3 of the rotor core 1 is used to cover each non-magnetic plate 4 and each permanent magnet plate 5. It is fitted and fixed to one outer peripheral surface formed by 5. The portion of the cladding tube 7 that the non-magnetic plates 4 contact is made of a non-magnetic member 8, and the portion of the cladding tube 7 that the permanent magnet plates 5 contact is made of a magnetic member 9. Each non-magnetic member 8 and each magnetic member 9 are joined using a special welding method such as electron beam welding. Also, Figure 2 (b
), a cylindrical fixing ring 10 is fitted and fixed on the outer circumferential surface 3 near both ends of the rotor core 1, and both ends of the cladding tube 7 are joined to the outer circumferential surface of each of the fixing rings 10 by welding. are doing. Furthermore, in contact with each end surface 11 of the rotor core 1,
An annular end plate 13 is provided in the center with a hole 12 through which the rotating shaft 2 passes and whose outer diameter is equal to the outer diameter of the fixing ring 10. It is fixed to the end of 7 by welding.

In the permanent magnet rotor having such a configuration, the outer peripheral surfaces of each non-magnetic plate 4 and each permanent magnet plate 5 are covered with the cladding tube 7, so even if each non-magnetic plate 4 and the rotating iron core 1 or between each permanent magnet plate 5 and the outer circumferential surface 3, the centrifugal force generated when the permanent magnet rotor rotates at an ultra-high speed will cause each of the above It is possible to prevent parts from scattering.

For example, number of poles: 4, output: 37 kW, number of rotations: 2
When designing a motor with a rating of 0.00 Orpm, it is necessary to set the thickness of each permanent magnet plate 5 to about 10+n+n-12 m. Assuming that the centrifugal force due to the total weight of the permanent magnet plate 5 having the above-mentioned thickness is applied to the inner circumferential surface of the cladding tube 7, the wall thickness of the cladding tube 7 may be set to about 3 cm to 3.5 mm. In this case, the internal stress generated within the cladding tube z is approximately 6
0 kgf/rra2, and the non-magnetic member 8 and the magnetic member 9 are connected by welding as described above so as to sufficiently withstand this internal stress. Furthermore, rotor core 1
Since both ends of the non-magnetic plate 4 and the permanent magnet plates 5 are covered with the end plates 13, it is possible to prevent each non-magnetic plate 4 and each permanent magnet plate 5 from shifting in the axial direction. Furthermore, since each permanent magnet plate 5 is covered with a cladding tube 7 and is not directly exposed to the outside, it is possible to prevent each permanent magnet 5 from being damaged by mechanical shock or the like. Therefore, the safety and reliability of the permanent magnet rotor can be completely improved.

Note that since the outer peripheral surfaces of each non-magnetic plate 4 and each permanent magnet plate 5 are covered with a non-magnetic member 8 and a magnetic member 9, respectively, the magnetic flux 1 formed by each permanent magnet plate 5
4 is not significantly affected by the provision of the cladding tube 7.

Therefore, by using the permanent magnet rotor of this embodiment, it is possible to provide a motor that can improve safety and reliability while maintaining high efficiency, and can reduce manufacturing costs.

Note that the permanent magnet rotor according to the present invention is not limited to the embodiments described above. That is, in the embodiment, the rotor core is formed from one magnetic material, but the rotor core may be formed by laminating a plurality of thin plates. Further, in the embodiment, the fixing ring 10. Although the end plate 13 and both ends of the cladding tube 70 are connected to each other by welding, they may be connected using a strong adhesive or the like. Further, in the embodiment, the permanent magnet rotor has a four-pole configuration, but the number of poles may be set arbitrarily.

〔Effect of the invention〕

As explained above, according to the present invention, a plurality of permanent magnets and a plurality of non-magnetic materials are attached alternately along the circumferential direction to the outer circumferential surface of the rotating body using, for example, adhesive or welding. In contrast to the conventional manufacturing method, in which a yoke with a recessed portion for accommodating a permanent magnet was manufactured by press working, and the yoke was laminated to form the rotor core as a rotating body. In comparison, manufacturing time can be shortened and manufacturing costs can also be reduced.

Furthermore, in the permanent magnet rotor manufactured by the above manufacturing method, since a non-magnetic body is interposed between each permanent magnet, leakage magnetic flux generated between adjacent permanent magnets can be reduced. As a result, the efficiency of rotating electric machines such as motors using this permanent magnet rotor can be improved.

In addition, the part that each permanent magnet comes into contact with is made of a magnetic material, and the part that each non-magnetic material comes into contact with is made of a non-magnetic material. In this case, the above-mentioned parts can be prevented from being scattered due to centrifugal force, so it is possible to improve safety and reliability while maintaining high efficiency, and to provide a motor that can reduce manufacturing costs. A magnetic rotor can be obtained.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a permanent magnet rotor according to an embodiment of the present invention, and FIG. 2 (, ) is a cross-sectional view showing a schematic configuration of a permanent magnet rotor according to another embodiment of the present invention. FIG. 2(b) is a sectional view showing a main part of the permanent magnet rotor. DESCRIPTION OF SYMBOLS 1... Rotor core, 2... Rotating shaft, 3... Outer peripheral surface, 4... Non-magnetic plate, 5... Permanent magnet plate, 6, 14
... magnetic flux, 7 ... cladding tube, 8 ... non-magnetic material member,
9... Magnetic member, 10... Fixed ring, 11...
- End face, 12-... hole, 13... end plate.

Claims (4)

[Claims] (1) A rotating body, a plurality of permanent magnets arranged at predetermined intervals along the circumferential trap on the outer circumferential surface of the rotating body, and a plurality of permanent magnets arranged between each of these permanent magnets, and a plurality of permanent magnets arranged between each of the permanent magnets. A permanent magnet rotor comprising: a plurality of non-magnetic materials filling a space formed in the permanent magnet rotor. (2) In a method for manufacturing a permanent magnet rotor in which a plurality of permanent magnets are arranged at predetermined intervals on the circumference, each of the permanent magnets and a non-magnetic material are arranged along the circumferential direction on the outer circumferential surface of the rotating body. A method for manufacturing a permanent magnet rotor, which is characterized in that the rotors are installed alternately. (3) A rotating body, a plurality of permanent magnets disposed on the outer peripheral surface of the rotating body at predetermined intervals along the circumferential direction, and a plurality of permanent magnets disposed between each of these permanent magnets, A plurality of non-magnetic materials that fill the spaces formed between the plurality of non-magnetic materials, and a portion that commonly covers each of the permanent magnets and each of the non-magnetic materials, and a portion that comes into contact with each of the permanent magnets is formed of a magnetic material, and A permanent magnet rotor comprising a cladding tube whose abutting portion is made of a non-magnetic material. (4) In a method for manufacturing a permanent magnet rotor in which a plurality of permanent magnets are arranged at predetermined intervals on the circumference and a cladding tube that commonly covers each of the permanent magnets is arranged, the outer periphery of the rotating body is The permanent magnets and the non-magnetic material are attached alternately along the circumferential direction on the surface, the portion of the cladding tube that comes into contact with the permanent magnet is made of a magnetic material, and the part that comes into contact with the non-magnetic material is made of a non-magnetic material. A method for manufacturing a permanent magnet rotor, comprising forming the rotor from a magnetic material, and then fitting and fixing the cladding tube to an outer circumferential surface formed by each of the permanent magnets and each non-magnetic material.