JPH07123341B2 - Shaft integrated magnet rotor and method for manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnet rotor in which a magnet body and a shaft are integrated by extrusion processing, and a method for manufacturing the magnet rotor.

[0002]

2. Description of the Related Art As an anisotropic magnet material, a sintered product obtained by pressing while in a magnetic field and anisotropy by aligning the magnetic axes and anisotropy, and anisotropy in a plasticizing direction or a direction perpendicular thereto by plastic working It is roughly divided into two types: plastic processed products. In a conventional magnet rotor, arc-shaped magnet pieces are arranged so as to form a cylindrical shape around a cylindrical shaft axis, and are fixed by a press fitting or a bind wire or tape is wound around the outer circumference of the magnet shaft to form a shaft with the shaft. A method of fixing the surrounding magnet pieces is adopted. However, covering the outer circumference with an appropriate material causes a decrease in magnetic flux and raises the manufacturing cost.

[0003]

By the way, it is possible to use at least a ring-shaped magnet anisotropy in the radial direction by plastic working instead of using the arc-shaped magnet piece. When attaching the shaft as the rotor's rotating shaft to its center, the magnet material is fragile, making machining difficult, such as drilling and threading, and using a method such as caulking to place the shaft material in the center. It is impossible to insert it. Further, since joining processing such as welding and brazing is also difficult, a mounting member having a complicated structure is used, fixing is performed with an adhesive, or ZnAl or the like is poured into the joining interface between the shaft and the magnet material. A method of insert molding is adopted.
However, there is a problem that the manufacturing process becomes complicated. Therefore, an object of the present invention is to provide a magnet rotor in which a shaft and a magnet body are integrated by extrusion processing.

[0004]

The shaft-integrated magnet rotor according to the present invention utilizes this property because the Nd-Fe-B magnet material can be anisotropy in the direction perpendicular to the plasticizing direction by plastic working. By extruding the shaft material and powder magnetic material at the same time, it is possible to integrate with the shaft and at the same time, the magnet main body around the shaft is made anisotropic in the radial direction. Rotation of a cylindrical magnet body which is anisotropy in the radial direction by machining and a rotor which is fitted in the center of the magnet body and whose joint boundary surface is metallographically joined to the center by extrusion. It is in a shaft-integrated magnet rotor consisting of a shaft and a shaft.

When the shaft material and the magnet material around the shaft are simultaneously extruded, the solid metal material for the shaft is inserted concentrically with the capsule into a cylindrical capsule made of metal having sufficient strength and ductility. , Filling the remaining space in the capsule with a powder magnetic material, sealing the capsule and extruding in the axial direction,
It is preferable to employ a method of manufacturing a shaft-integrated magnet rotor by cutting both ends of the extruded semi-finished product to form shaft ends and removing the outer peripheral capsule material to expose the magnet body.

[0006]

According to the present invention, the Nd-Fe-B-based powder material around the shaft material changes into a solid material during extrusion, and the extruded shaft and the enriched magnet body are metallurgically bonded. At the same time, it is anisotropy in the radial direction.

At the time of extrusion processing, a capsule is required for filling the shaft material and the powder material constituting the magnet around the shaft material. In consideration of strength and extensibility during extrusion processing, it is preferable to use SC material as the tubular material and pure Fe thick plate as the lid material as the capsule material.

Materials that produce magnetic anisotropy in the radial direction by extrusion are Nd-Fe-B and Pr-Fe-.
B type is well known, and the former includes pulverized powder and gas atomized powder from a quenched ribbon produced by melt spinning, and the latter produces the powder obtained by pulverizing a casting material in addition to the above two methods. However, any of these may be used in the present invention.

The shaft material is a solid metal material having a deformation resistance equivalent to that of the magnet-based alloy at the processing temperature, and a good shape with the magnet body formed from the powder material at the time of extrusion processing. Are preferable, and specific examples thereof include materials such as brass and copper.

Although the extrusion processing conditions may be warm, the extrusion temperature is about 600 to 80 in terms of productivity and yield.
The range of 0 ° C is preferable, and the strain rate at that time is about 0.1.
The range is preferably 0.01 mm / s and an extrusion ratio of 2-8. After the extrusion processing, the outer peripheral encapsulant is removed to expose the inner magnet body, but this may be performed by cutting or grinding. If the dummy materials at both ends are left as part of the end rings, the coupling strength between the shaft and the magnet body is improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to specific examples shown in the accompanying drawings. FIG. 1 is a sectional view showing a manufacturing process of a shaft-integrated magnet rotor according to the present invention.
A bottom cover 2 made of the same material is welded to a cylindrical capsule 1 made of material, a brass shaft material 3 is fitted into a fixing hole 2a formed in the center of the bottom cover 2, and a Nd-
A Fe-B-based powder 4 is filled and a top lid 5 having the same shape as the bottom lid 2 is formed.
Is fitted on the upper end of the shaft material 3, and the opening of the capsule 1 is closed and welded.

Next, the filled capsule 1 is heated to 720 ° C.
It is heated for 10 minutes and loaded into a capsule extruder, and is subjected to warm extrusion processing at an extrusion temperature of 720 ° C., a strain rate of 0.1 mm / s, and an extrusion ratio of 2 to enrich the filling powder and extrude it. At the same time that the shaft material 3 and the enriched magnet body 6 are metallurgically bonded, the Nd-Fe-B system magnet body is anisotropy in the radial direction by extrusion.

Next, the upper lid 5 and the bottom lid 2 are cut by a small emery while leaving both ends formed by extrusion processing, and a center hole 13 is formed in the center of both exposed ends of the shaft material 3. Next, the stretched outer peripheral capsule 1 is cut and removed to expose the outer periphery of the magnet body 11. Finally, both ends are turned to machine the shaft 12, and both ends are further cut to form the end plates 14.

Therefore, the shaft-integrated magnet rotor is Nd which is anisotropic in the radial direction by extrusion.
-Fe-B system cylindrical magnet main body 11 and the main body of the magnet main body 11 are fitted into the central portion thereof, and the joint boundary surface of the main body constitutes the rotation axis of the rotor, which is metallographically coupled to the central portion by extrusion. The magnet main body 11 has end plates 14 made of pure Fe at both ends, and center holes 13 at both ends of the shaft 12.

[0015]

As is apparent from the above description, according to the present invention, the powder material around the shaft material changes into a solid material at the time of extrusion processing, and the extruded shaft and the solidified magnet body are made of metal. At the same time histologically combined
Since the magnet body will be enhanced by extrusion and become anisotropic in the radial direction, it is necessary to provide a shaft-integrated magnet rotor that is structurally stable and has excellent magnet performance, which was previously difficult. You will be able to

[Brief description of drawings]

FIG. 1 is a sectional view showing a manufacturing process of a shaft-integrated magnet rotor according to the present invention.

[Explanation of symbols]

 1 Cylindrical Capsule 3 Shaft Material 4 Magnet Powder Material 10 Magnet Rotor 11 Magnet Main Body 12 Shaft 14 End Plate

Claims (2)

[Claims] 1. A cylindrical magnet main body which is anisotropy at least in a radial direction by extrusion, and is inserted into a central portion of the magnet main body, and a joint boundary surface of the magnet main body is formed on the central portion by extrusion processing. A shaft-integrated magnet rotor, comprising: 2. A solid metal material for a shaft is inserted into a cylindrical capsule made of a metal having sufficient strength and ductility concentrically with the capsule, and the residual space in the capsule is filled with a powder magnet material. This capsule is hermetically sealed and extruded in the axial direction, both ends of the extruded semi-finished product are cut to form shaft ends, and the outer peripheral capsule material is removed to expose the magnet body. And method for manufacturing a shaft-integrated magnet rotor.