JPS58222767A - Flat rotary electric machine - Google Patents

Abstract

PURPOSE:To perform skew effect at poles with a permanent magnet of standard type by employing the first and second permanent magnet pieces cut from the permanent magnet of standard shape having outer and inner peripheral sides and in which extension lines of both sides cross at the axial core. CONSTITUTION:Many first and second permanent magnet pieces 1a, 1b divided from a permanent magnet of sector shape of standard type having outer and inner peripheral sides and in which extension lines of both sides cross at the axial center O in such a manner that the inner and outer peripheral arcuate parts are cut in a line (l2) inclined at the prescribed angle theta to the line (l1) passing the axial center O therebetween, are prepared. The inner and outer peripheral sides of the first or second pieces or the first and second pieces are formed to be coincident, combined in the shape except the standard type, and bonded to form poles.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a flat rotating electric machine used, for example, as a servo motor, and particularly to a flat rotating electric machine in which magnetic poles made of permanent magnets attached to a rotor are improved.

[Technical background of the invention]

For example, a flat rotary electric machine is a servo motor installed in a part whose dimension in the axial direction is extremely limited, such as an arm of a manipulator.

This flat rotating electric machine includes a rotor in which magnetic poles are formed by attaching a plurality of permanent magnets at equal intervals to a disc made of a ferromagnetic material attached to a rotating shaft, and a rotor that surrounds the rotor. A device consisting of a stator core having an armature winding attached to a frame provided in a stator with an axial air gap attached to the magnetic pole mounting surface of the rotor. In electric machines, the magnetic poles attached to the rotor have an inner circumferential arc portion and an outer circumferential arc portion, as shown in Figure 1, and the extension lines of both sides are aligned with the axis 0.
As a standard type, permanent magnets 1 having a fan shape intersecting at , are attached to one plate surface of a disk 2 at equal intervals as shown in the figure, and are configured as a six-pole machine, for example.

[Problems with background technology]

However, when a flat rotating electrical machine in which the rotor magnetic poles are formed using such a standard permanent magnet 1 is operated as a servo motor, cogging)/9 will occur because the magnetic poles have no skew. , making stable operation difficult.

Furthermore, in a flat rotating electric machine, if it is desired to change the number of magnetic poles of the rotor, several types of permanent magnets having the same shape as the permanent magnet 1 but different in size must be prepared. However, rare earth magnets such as samarium cobalt are usually used for this type of permanent magnet, so preparing several types of permanent magnets is not a fool's errand as there are manufacturing problems due to mold processing, and there is a lot of waste. It is uneconomical.

[Object of the Invention] The present invention was made in view of the above-mentioned circumstances, and its purpose is to make it possible to exert a skew effect on the magnetic poles using a standard permanent magnet, and to make it possible to change the number of poles easily and inexpensively. The object of the present invention is to provide a flat rotating electric machine that can be used in the following manner.

[Summary of the invention]

In order to achieve this object, the present invention uses a standard permanent magnet that has an outer peripheral part and an inner peripheral part, and the extension lines of both sides intersect at the axis. Among the first permanent magnet piece and the second permanent magnet piece having different shapes obtained by cutting the straight line τ at a predetermined angle with respect to the straight line passing through the axis, the first or second permanent magnet piece is The magnet pieces or the first and second permanent magnet pieces are 1.

A magnetic pole is constructed by matching the outer periphery and combining and joining them in a shape other than the standard type.

An embodiment of the present invention will be described below with reference to the drawings. Second
The figure is a plan view for explaining the case where magnetic poles made of permanent magnets are formed on one plate surface of a disc-shaped rotor in a flat rotating electrical machine. indicates a skewed magnetic pole part. That is, in this example, as shown in part (A) of Fig. 2, it has an inner circumferential arc part and an outer circumferential arc part, and the extension lines of both sides intersect at the axis 0. The fan-shaped permanent magnet 1 is a standard type (same as the permanent magnet 1 shown in FIG. 1), and the axis between the inner circumferential arc portion and the outer circumferential arc portion is the axis O.
A straight line t that is inclined by a predetermined angle θ with respect to the straight line L1 passing through ! A large number of magnets are prepared by cutting them into two pieces, a first permanent magnet piece 1a and a second permanent magnet piece 1b.

In this case, the permanent magnet 1 can be easily cut by wire cutting or electrical discharge machining. The thus obtained first permanent magnet M' 1 g and second permanent magnet piece 1b
In order to form, for example, six magnetic poles with a skewed shape on one plate surface of the disk 2 using are joined so that their inner and outer circular arc parts match.

Therefore, if the magnetic poles of the rotor have such a configuration, the first permanent magnet piece 1 obtained by cutting the standard permanent magnet 1
It is possible to create a skew simply by combining and joining a and the second permanent magnet piece 1b, so when this is used as a rotor of a motor, cogging)/l/ri(
Smooth operation with low pulsating torque is possible.

In addition, the standard permanent magnet 1 can be easily cut at any 7-angle angle by electrical discharge machining.
In particular, it is not necessary to manufacture permanent magnets having shapes with various skew angles by mold processing, and the skew effect can be exhibited easily and inexpensively.

In the above embodiment, a case has been described in which six magnetic poles having a skewed configuration are formed on one plate surface of the disk 2. Next, the first permanent magnet piece 1a or the second permanent magnet piece 1a A case will be described in which the pieces 1b are combined to form magnetic poles having different numbers of magnetic poles and skews. FIG. 3 is a plan view similar to FIG.
The number of magnetic pole parts is shown when there are more than those shown in the figure. In other words, if the number of magnetic poles is slightly smaller than that in Figure 2, e in Figure 3 is used.
) The first permanent magnet piece 1 explained in FIG.
A are joined to each other so that the inner and outer peripheral arcuate portions of the side portions opposite to the cut portions coincide with each other. In addition, if you want to increase the number of magnetic poles compared to the one shown in Figure 2, as shown in Part 0 of Figure 3, the second permanent magnet pieces 1b explained in Figure 2 should be cut together on the side opposite to the cutting part. They are joined so that their inner and outer circumferential arcuate portions are aligned.

Therefore, if the magnetic poles of the rotor are configured in this manner, the number of magnetic poles can be changed with a skewed shape by simply combining and joining the first permanent magnet pieces 1h or the second permanent magnet pieces 1b. There is no need to prepare several types of permanent magnets of different sizes as in the past, and a highly versatile and inexpensive magnetic pole with little waste can be obtained. Furthermore, since either combination results in a skewed shape, it goes without saying that when this is used as a rotor of a servo motor, operation with small cogging torque can be achieved as described above.

In the above embodiment, the standard permanent magnet is fan-shaped with an outer circular arc portion and an inner circular arc portion, but it does not necessarily have to be fan-shaped. It may also be trapezoidal with a straight circumferential arc,
Alternatively, one of the inner and outer circumferential arcuate portions may be formed in a straight line.

Furthermore, in the above embodiments, a synchronous machine with magnetic poles on the rotor side was described, but when a DC machine is used, the above-mentioned method can also be applied to the magnetic poles formed on the stator side. It is something that can be done.

〔Effect of the invention〕

I□statement, let's go to the main station□yoyowai, ah, junior. -I
It is possible to provide a flat rotating electric machine in which a skew effect can be exerted on magnetic poles using permanent magnets, and the number of poles can be changed easily and at low cost.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the magnetic pole configuration of a rotor in a conventional flat rotating electric machine, FIG. 2 is a plan view showing a magnetic pole configuration of a rotor in an embodiment of the present invention, and FIG. 3 is a plan view showing a magnetic pole configuration of a rotor in an embodiment of the present invention. FIG. 3 is a plan view showing the magnetic pole configuration in the embodiment. l...Permanent magnet, 1m, Ib...Permanent magnet piece, 2.
...disk. Applicant Sub-Agent Patent Attorney Takehiko Suzue Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A disk-shaped rotor is attached to a rotating shaft, and an axial air gag is provided to one plate surface of the rotor, and the frame is attached to the inner surface of a frame that is provided to surround the rotor. In a flat rotating electric machine, the rotor or the stator has a magnetic pole made of a permanent magnet on one side, and an armature winding on the other side, and the magnetic pole has an inner peripheral portion and an outer peripheral portion. A standard permanent magnet having a peripheral part and extension lines of both sides intersecting at the axis is inclined at a predetermined angle between the inner peripheral part and the outer peripheral part with respect to a straight line passing through the axis. Of the first permanent magnet piece and the second permanent magnet piece that have a shape obtained by cutting along a straight line, the first or second permanent magnet pieces or the first and second permanent magnet pieces are cut inside and outside. 1. A flat rotary electrical machine, characterized in that the peripheral parts are made to match and the machine is combined and joined in a shape other than the standard shape.