JP2925991B2 - Rotor for electrical equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor for electric equipment and, more particularly, to a rotor suitable for use in a high-speed rotating machine such as an electric motor or a generator for railway vehicles. In particular, the present invention relates to a structure of a rotor having end plates made of a brittle material such as a high magnetic permeability iron core containing cobalt at both axial ends of the iron core.

[0002]

2. Description of the Related Art A conventional cage rotor used in an induction motor is shown in FIG. FIG. 3A is a front view,
FIG. 3B is a side view. In these figures, 1 is an iron core, 2 is an end plate made of a high magnetic permeability material containing an iron-cobalt alloy, 3 is a conductor, 4 is an iron core holder, and 5 is a rotor shaft.

In the above configuration, since the iron cores 1 are laminated under pressure, an axial reaction force is always applied after lamination. To prevent the core 1 from opening in the axial direction due to this reaction force, both ends in the axial direction of the core 1 are pressed by the core holder 4 via the end plate 2. However, as shown in FIG. 4, since the conductor 3 is inserted into the slot 1a of the iron core 1, the iron core presser 4 can press the iron core 1 only to the roots of the teeth (both sides of the slot 1) of the iron core 1. Can not.

For this reason, as shown in FIG. 5, the vicinity of the outer peripheral portion of the iron core retainer 4 is locally pressurized, and the stress concentrates at the root of the slot 1 and the p point of the root of the tooth due to the reaction force. Normally, end plates 2 are inserted at both ends in the axial direction of the iron core 1 in order to prevent the teeth of the iron core 1 from opening and to reduce the stress generated at the root of the teeth by the iron core holder 4. .

[0005]

Since the end plate 2 is a part of a magnetic circuit, a high permeability material such as an iron-cobalt alloy is used. It uses several sheets of iron core material that are stacked and spot welded together. For this reason, the rigidity of the end plate 2 is generally lower than that of a thick plate having the same thickness, and although it has an effect of preventing the opening of the teeth of the iron core 1, it is insufficient to prevent stress concentration at the root of the teeth. there were.

That is, in the above conventional technique, there is no particular problem when the rotor rotates at a low speed or when the material of the end plate 2 has a sufficient strength. However, when the tensile stress accompanying the high-speed rotation of the rotor is large or when the material of the end plate 2 is brittle, the end plate 2 is broken from the root of the tooth portion due to stress concentration, and this is scattered and the stator coil is damaged. Serious accidents may be caused by breaking insulation.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to prevent breakage and scattering of teeth due to stress concentration even when an end plate is formed of a magnetic material having a brittle strength. An object of the present invention is to provide a rotor for an electric device that can prevent the occurrence of a rotation.

[0008]

To achieve the above object, according to the first aspect of the present invention, an end plate made of a magnetic material having teeth is fixed to both ends in the axial direction of an iron core having teeth. In a rotor for electrical equipment having an iron core retainer fixed to the outside thereof, a high-rigidity end plate retainer made of a non-magnetic material is formed between the end plate and the iron core retainer so as to overlap the teeth of the end plate. It is arranged.

According to a second aspect of the present invention, in the electric device rotor, the end plate retainer connects a plurality of teeth overlapping with the teeth of the end plate, and connects these teeth. A connection portion that overlaps with the iron core retainer.

[0010] In the present invention, the stress caused by the iron core pressing at the tooth base of the end plate is absorbed and dispersed by the end plate pressing and applied to the end plate, and is not directly applied to the tooth base. For this reason, the tooth portion of the end plate does not break from the root when the rotor rotates at a high speed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The same components as those in the prior art are denoted by the same reference numerals, detailed description thereof will be omitted, and different portions will be mainly described below. FIG. 1 shows an embodiment in which the present invention is applied to a cage rotor of an induction motor.
1A is a front view, and FIG. 1B is a side view.

In these figures, reference numeral 6 denotes an end plate retainer. The end plate retainer 6 is formed of a non-magnetic material such as stainless steel and a thick rigid plate. As shown in FIG. 2, the front shape of the end plate retainer 6 is completely identical to the end plate 2 or, as shown in FIG. 2, formed to have a tooth portion 6a slightly lower than the tooth portion 2a of the end plate 2. In FIG. 1B and FIG. 2, reference numeral 6b denotes a connecting portion for connecting the plurality of tooth portions 6a to each other. The connecting portion 6b overlaps the iron core retainer 4, and the tooth portions 6a are the teeth of the end plate 2. Polymerized in part 2a.

The shape of the end plate retainer 6 is the same as that of the iron core retainer 4.
It is desirable that the shape be such that the stress concentrated on the root of the tooth portion 2a of the end plate 2 is widely dispersed so that the outer peripheral surface of the tooth portion 2a is in contact with a large area. Here, the end plate retainer 6 needs to be formed of a non-magnetic material so as not to cause eddy current loss, and the material is not limited to metal but may be hard plastic or the like.

The end plate retainer 6 is attached to the outside of the end plate 2 at both ends in the axial direction of the iron core 1, and the iron core retainer 4 is further fixed to the outside thereof.

With this construction, even when a fragile high permeability material is used for the end plate 2, the stress concentration at the point p shown in FIG. 1B is absorbed and dispersed by the end plate retainer 6, There is no direct contact with the root of the tooth portion 2a of the end plate 2. For this reason, even when the rotor rotates at high speed, there is no possibility that the tooth portion 2a is broken from the root thereof, and there is no fear that the stator or the like is damaged by scattering of chips.

The present invention is applicable not only to a cage rotor of an induction motor, but also to a rotor having a structure in which an iron core having teeth and an end plate are fixed from the outside by an iron core retainer. It can also be applied to machine rotors.

[0017]

As described above, according to the present invention, breakage of the teeth of the end plate can be prevented beforehand by the end plate retainer disposed between the iron core retainer and the end plate. A highly reliable rotor can be realized by preventing various accidents caused by the scattering of the rotor. Further, the structure of the end plate holder itself is extremely simple, and both the manufacturing cost and the assembly cost are inexpensive, so that it is economical.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention (FIG. 1);
(A)) and a side view (FIG. 1 (b)).

FIG. 2 is a perspective view showing a portion A in FIG. 1A in detail.

FIG. 3 is a front view (FIG. 3A) and a side view (FIG. 3B) showing a conventional technique.

FIG. 4 is a perspective view showing a portion B in FIG. 3A in detail.

FIG. 5 is an explanatory diagram of a problem of the related art.

[Description of Signs] 1 Iron core 1a Slot 2 End plate 2a Tooth portion 3 Conductor 4 Iron core holding 5 Rotor shaft 6 End plate holding 6a Tooth portion 6b Connecting portion

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Osamu Shibano 1-1-1, Tanabe-shinda, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside Fuji Electric Co., Ltd. (56) References JP-A-5-344666 (JP, A) JP-A-7-298583 (JP, A) JP-A-8-182275 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02K 17/16 H02K 1/02

Claims (2)

(57) [Claims] 1. A rotor for electric equipment, comprising: an end plate of a magnetic material having a tooth portion fixed to both ends in an axial direction of an iron core having a tooth portion; and an iron core retainer fixed to the outside thereof. A rotor for electric equipment, wherein a high-rigidity end plate retainer made of a non-magnetic material is arranged between a plate and an iron core retainer so as to overlap the teeth of the end plate. 2. The rotor for an electric device according to claim 1, wherein the end plate retainer includes a plurality of teeth overlapping with the teeth of the end plate, the teeth being connected, and the iron core retainer being connected to the iron core retainer. A rotor for electric equipment, comprising: a connecting portion that overlaps.