JPS62203539A - Rotor of commutatorless motor - Google Patents

Abstract

PURPOSE:To prevent a permanent magnet from dropping from a sleeve by forming a recess on the end face of the magnet, and so forming as to intrude an integrally molding material such as a die casting material to the recess. CONSTITUTION:Both end faces 4a of a cylindrical permanent magnet 4 coaxially coupled with a sleeve 2 and a die cast portion 3 engaged with a drive shaft 1 are deeply inclined to the bore sides of the magnet 4. Two recesses 6 which are ended at the insides of the outer periphery of the magnet 4 are so formed as to be axially symmetrically, and so die cast as to intrude the die casting material into the recesses 6. Thus, it can prevent the magnet 4 from dropping to prevent the magnet 4 from slipping.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rotor for a commutatorless motor, and in particular, to a rotor for a non-commutator motor, and in particular to a rotor that uses a cylindrical permanent magnet to be integrated with other components such as a sleeve for fitting a drive shaft. The present invention relates to a rotor for a commutatorless motor that is suitable for those that are torn by molding.

[Conventional technology]

For example, compressors used in refrigerators, air conditioners, etc. are generally driven by shaft-directly connected motors, and both are hermetic compressors housed in one sealed container.

Conventionally, induction motors have been used in these hermetic compressors, but commutatorless motors have recently begun to be used because they are easy to control the rotational speed and have high efficiency.

For example, in the non-commutator motor described in JP-A-56-19369, in order to prevent the permanent magnets of the rotor from falling off the yoke, the permanent magnets and the yoke or end plates are fitted into each other, and the fitted part or A rotor with a locking section is used.

In the rotor of the commutatorless motor in the publication, the permanent magnets and the yoke or end plates are connected by fitting or locking means, but on the other hand, in recent commutatorless motors, the permanent magnets are assembled by die-casting. It's starting to look like this.

[Problem that the invention seeks to solve]

When the permanent magnets used in the rotor of commutatorless motors are assembled by die-casting, the die-casting materials such as aluminum and zinc deteriorate over time due to stress caused by repeated heating and cooling, or mechanical stress applied during starting and stopping. The strength of the compressor decreases, which may eventually lead to problems such as the permanent magnet idling or falling off, and in this case, the motor no longer generates torque, resulting in a loss of compressor function.

The present invention has been made to solve the above-mentioned problems, and its object is to provide a rotor for a commutatorless motor in which the cylindrical permanent magnet used in the rotor does not idle.

[Means for solving problems]

In order to solve the above-mentioned problems, the rotor of the commutatorless motor according to the present invention has a structure including a cylindrical permanent magnet, a sleeve located on the inner diameter of the permanent magnet and attached to the drive shaft. A rotor for a commutatorless motor in which the permanent magnets and the sleeve are configured concentrically, and the gap between the permanent magnet and the sleeve and the end face part of the permanent magnet are integrally molded with a molding material, , a plurality of recesses are formed that are inclined to become deeper toward the inner diameter side of the permanent magnet and end inside the outer diameter portion of the permanent magnet, and the molding material is bitten into the recesses. It is.

[Effect]

The effects of such technical means will be explained in accordance with the idea behind developing the present invention.

゛ゝCylindrical permanent magnets are made of powder such as barium ferrite.
Although it is produced using advanced metallurgy, if the shape and dimensions are not uniform and isotropic, cracks and deformation will occur when the permanent magnet is fired, resulting in poor production yields, lower productivity, and higher costs. .

In order to prevent such defects, the present invention provides the above-mentioned recess on the end face of the permanent magnet, and molds the material to be integrally molded, such as die-cast material, into the recess. The magnet does not fall off the sleeve, and the permanent magnet can be prevented from spinning idly.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 6.

First, FIGS. 1 and 2 show a rotor of a commutatorless motor according to an embodiment of the present invention, and FIG.
Figure 2 is a longitudinal sectional view, Figures 6 and 4 show the permanent magnet, Figure 6 is a front view as seen from the end side, and Figure 4 is a longitudinal sectional view.
The figure is a longitudinal sectional view.

In the figure, 1 is a drive shaft, and 2 is a sleeve. This sleeve 2 is firmly fitted onto the drive shaft 1 by means such as shrink fitting or press fitting.

4 is a cylindrical permanent magnet, and this permanent magnet 4 is molded using powder metallurgy such as barium ferrite.

5 is a protective tube that protects this permanent magnet 4;
The protective tube 5 is made of a non-magnetic material with high electrical resistance, such as stainless steel, and is molded into a cylindrical shape.

These sleeves 2, permanent magnets 4, and protective chips 5
are integrally formed by die-casting. That is, 6 is a die-casting molded part in which the cylindrical permanent magnet 4 and the sleeve 2 are kept concentrically, and the gap between the permanent magnet 4 and the sleeve 2 and both end surfaces of the permanent magnet 4 are integrally molded by die-casting. It is. Aluminum, zinc, etc. are used as materials for die casting.

As shown in Fig. 6.4, an even number of magnets are arranged on both end faces 4a of the cylindrical permanent magnet 40 (in Fig. 5.4, each end face 2) recesses 6 are formed in each case. The recess 6 has a shape that is inclined to become deeper toward the inner diameter of the permanent magnet 4 and ends inside the outer diameter of the permanent magnet 4.

The permanent magnet 4 is manufactured by powder metallurgy of barium ferrite, but the thickness must be made uniform in order to minimize the occurrence of cracks and deformation when fired at high temperatures in a furnace.

To meet this requirement, the recess 6 may be formed with a deep inner diameter and an inclination, and the end of the recess is inside the outer diameter, as shown in Figure 6.4. , confirmed by the results of prototype experiments.

When a die-cast molding material is integrally formed on the permanent magnet 4 in which the recessed portion 6 is formed, the die-cast molding material becomes the permanent magnet 4.
It is molded so as to bite into the four parts 6 of the.

According to the non-implementation case 11, the sleeve 2 fitted onto the drive shaft 1
Both end surfaces 4a of the cylindrical permanent magnet 4 concentrically connected to the die-cast molded part 3 are inclined so as to become deeper toward the inner diameter side of the permanent magnet 4, and the outer diameter of the permanent magnet 4 is Two recesses 6 each ending inside the section are formed axially symmetrically,
By die-casting the die-cast molded material so as to bite into the recess 6, the permanent magnet 4 is prevented from falling off, and idling of the permanent magnet 4 can be reliably prevented.

Next, another embodiment of the present invention will be described with reference to FIGS. 5 and 6.

5 and 6 show permanent magnets according to other embodiments of the present invention, in which FIG. 5 is a front view, FIG. 6 is a longitudinal sectional view, and FIGS. are drawings corresponding to the previous FIGS. 3 and 4, respectively.

On both end faces 4a of the cylindrical permanent magnet 4, as shown in Fig. 5.6, an even number of axially symmetrical magnets (in Fig. 5.6, 4 magnets are placed on each end face).
recesses 7 are formed.

This recessed portion 7 has a shape that is inclined to become deeper toward the inner diameter side of the permanent magnet 4 and ends inside the outer diameter portion of the permanent magnet 4.

According to the embodiment shown in FIGS. 5.6, exactly the same effects as those described in the embodiment shown in FIGS. 1 to 4 can be expected.

Note that the protection team explained in the embodiment of Fig. 1.2 above
As mentioned above, the cover 5 is for protecting the permanent magnet 4, and does not need to be made of metal as long as it meets the purpose, and may be made of synthetic resin, glass fiber assembly, or the like.

Further, if the permanent magnet 4 has sufficient strength and does not require protection, the protective tube 5 may be omitted.

In addition, although the above-mentioned embodiment described a rotor formed by die-casting, the present invention is not limited to die-casting, and if heat resistance, mechanical strength, etc. are suitable,
For example, it can be processed by injection molding or compression molding using synthetic resin materials.

Note that the recess 6 described in each of the embodiments shown in FIGS.
Or, since an even number of recesses 7 are provided axially symmetrically, for example, in FIG. 3, four recesses 6 are provided on the top, bottom, left and right sides of both end faces, and in FIG. 5, two or six recesses 7 are provided on both end faces. There is absolutely no problem with this in view of the content of the present invention.

Furthermore, although the recesses 6 or 7 are shown to be provided on both end surfaces of the permanent magnet 4 in FIG. There is no problem in setting it up.

[Purpose of the invention]

As described above, according to the present invention, it is possible to provide a rotor for a commutatorless motor in which the cylindrical permanent magnet used in the rotor does not idle.

[Brief explanation of drawings]

1 and 2 show a rotor of a commutatorless motor according to an embodiment of the present invention, in which FIG. 1 is a cross-sectional view, FIG. 2 is a longitudinal cross-sectional view, and FIGS. 6 and 4. 3 shows the permanent magnet, FIG. 3 is a front view, FIG. m4 is a vertical cross-sectional view, and FIGS. , FIG. 5 is a front view, and FIG. 6 is a longitudinal sectional view. DESCRIPTION OF SYMBOLS 1... Drive shaft, 2... Sleeve, 6... Die-cast molding part, 4.4... Permanent magnet, 4a, 4a... End surface, 6.7... Recessed part. ~

Claims (1)

[Claims] 1. A cylindrical permanent magnet and a sleeve located on the inner diameter of the permanent magnet and to be fitted onto the drive shaft are configured concentrically, and the gap between the permanent magnet and the sleeve is A rotor for a commutatorless motor in which the end face portion of the permanent magnet is an integrally molded part made of a molding material, wherein the end face of the permanent magnet is inclined so as to become deeper toward the inner diameter side of the permanent magnet, and A rotor for a commutatorless motor, characterized in that a plurality of recesses are formed that end inside an outer diameter portion of a permanent magnet, and the molding material is bitten into the recesses. 2. The rotor of a commutatorless motor according to claim 1, wherein the integrally molded part made of a molding material is formed by die-casting. 3. The rotor of a commutatorless motor according to claim 1, wherein the integrally molded part made of a molding material is made by injection molding or compression molding of a synthetic resin material.