JPH03183334A - Permanent magnet rotor - Google Patents

Abstract

PURPOSE:To easily fix a spacer for wind damage prevention and to enable the use of a small spacer and to miniaturize it at low cost by fixing the spacer molded in integrated moulding, in the spaces arising at both end faces of each permanent magnet. CONSTITUTION:A permanent magnet 1 and yokes 2 and 3 are fixed with each other by fixing screws 6. For a spacer 4, to fill four places of spaces arising at both end faces of the permanent magnet 1, four pillars in accordance with the spaces are connected at the ends and are integrated. This spacer 4 consists of resin, and can be obtained cheaply by such a method as injection moulding, extrusion molding, or the like. For a ring 5, it is fixed after being set on the spacer 4, whereby it becomes the constitution that it does not scatter even in the case where the permanent magnet rotor rotates at high speed. Hereby, screw hole processing process for the spacer and the yoke and screw fastening process become needless, so it can be manufactured cheaply.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a permanent magnet rotor for an electric motor.

[Prior Art] An example of a conventional permanent magnet rotor is shown in FIG. As shown in FIG. 4, the gaps between both end faces of the permanent magnet 21 are filled with spacers 24 made of a non-magnetic material different from the yoke 23 made of soft magnetic material to prevent wind damage, and each of the four locations is filled with two fixed screw 2
5 to the yoke 22.

[Problems to be Solved by the Invention] However, in the prior art described above, in which the gaps are filled with non-magnetic spacers and each of the four locations is fixed with screws, the workability is low because the assembly is fixed with screws. Unfortunately, this method has the problem of high cost.

Further, when downsizing the permanent magnet rotor, the spacer also becomes smaller, which poses the problem that screw holes for fixing cannot be made, which limits miniaturization.

Therefore, the present invention is intended to solve these problems.The purpose of the present invention is to easily fix a spacer for windage prevention, and also to enable small spacers to be used, resulting in miniaturization at low cost. It provides a permanent magnet rotor.

[Means for Solving the Problems] A permanent magnet rotor according to the present invention includes a permanent magnet rotor composed of a permanent magnet and a yoke made of a soft magnetic material. It is characterized by fixing the spacer made by.

[Example] Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a perspective view of a permanent magnet rotor showing a first embodiment of the present invention. The permanent magnet 1 and 3 are yokes made of soft magnetic material such as iron, and the permanent magnet 1 and yoke 2.3 are fixed to each other by fixing screws 6. Reference numeral 4 denotes a spacer, and in order to simultaneously fill the four gaps created on both end faces of the permanent magnet, the spacer has four columnar shapes that match the shape of the gaps and are connected at their ends and integrated. This spacer 4 is made of resin, and can be obtained easily and cheaply by injection molding, extrusion molding, etc. to obtain this shape.The ring 5 is fixed after the spacer 4 is assembled, and the permanent magnet rotor is It has a structure that does not scatter even when rotating at high speed. The permanent magnet rotor obtained by this means does not require the conventional spacer and yoke screw hole machining process, and furthermore, the screw fastening work, and can be manufactured at low cost.

A perspective view of a permanent magnet rotor according to a second embodiment of the present invention is shown in FIG. 11 is a Sm-Co magnet which is a permanent magnet, 1
2 and 13 are yokes made of soft magnetic material such as iron, and permanent magnet 1
1 and yokes 12, 13 are fixed to each other by fixing screws 16. Since the outer diameter of the yoke 13 is larger than the outer diameter of the magnet 11, both ends of the yoke 13 touch the magnet 11 in the fixed state.
protrudes from the outer shape of

Reference numeral 14 denotes a spacer made of an elastic material (such as rubber), which can fill two gaps with one piece, and has an opening in the center with dimensions slightly smaller than the external dimensions of the magnet 11. ing. In order to attach the spacer 14, the elasticity of the spacer material is used to insert the spacer 14 through the yoke 13 from the outer circumferential direction of the permanent magnet rotor. At this time, the opening of the spacer is widened, and after passing through the yoke 13, the opening is reduced, and the inner surface of the opening comes into close contact with the side surface of the magnet 11, making it possible to fix it.

In this permanent magnet rotor, even when rotating at high speed, the protrusion at the end of the yoke 13 acts as a stopper and does not fly away.

Another significant point of this second embodiment is that there is a wide tolerance for the external dimensional accuracy of the permanent magnet.

In particular, when the permanent magnet rotor becomes smaller, the permanent magnets naturally also become smaller, and the external dimensions of the magnets are limited in terms of size. However, using this method, the variation in dimensions can be covered by the elastic component, so it is possible to reduce the size of the permanent magnets during mass production. The benefits are significant.

In this example, the permanent magnet is Sm-C.

Although magnets were used, the permanent magnet material is not limited to Sm-C0 magnets, and it goes without saying that various magnets such as Pr (braceo) magnets and ferrite magnets can be used in the same manner.

[Effects of the Invention] As described above, according to the present invention, when fixing the spacer to prevent windage damage in the gap between the permanent magnet rotors, there is no need to use screws and to assemble each part one by one, so the assembly time is reduced. can be shortened and costs can be reduced.

Another advantage is that there is no need to drill screw holes in the spacer when it comes to miniaturization, and even small spacers can be easily fixed, making it possible to freely manufacture large to small spacers. Furthermore, another effect is that when an elastic spacer is used, variations in the shape of the permanent magnet can be absorbed by the spacer, which widens the margin during mass production, and from this point of view as well, costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a permanent magnet rotor in a first embodiment of the present invention. FIG. 2 is a side view of FIG. 1 viewed from the axial direction. FIG. 3 is a perspective view of a permanent magnet right rotor in a second embodiment of the present invention. FIG. 4 is a side view of a conventional permanent magnet rotor viewed from the axial direction. 1...Permanent magnet 2...Yoke 3...Yoke 4...Spacer 5...Ring 6...Fixing screw that's all

Claims (1)

[Claims] A permanent magnet rotor comprising a permanent magnet and a yoke made of a soft magnetic material, in which a spacer made by integral molding is fixed in a gap formed on both end surfaces of the permanent magnet. Child.