JPH10290556A - Squirrel-cage rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a balance weight easily without requiring any independent unit by setting at least one copper bar of a rotor longer than other copper bars and subjecting the copper bar to aluminum diecasting. SOLUTION: A rotor 1 comprises a rotor core 4 having full-open slots 3 carried on a shaft 2, and secondary conductors formed by inserting a copper bar 5 and a copper bar 6 comprising copper bars 6a, 6b, 6c into full-open slots 3 and coupling the copper pars with an end ring 7 by aluminum diecast. The copper bar 6 (6A, 6B, 6C) is longer than the copper bar 5 in the axial direction. Since a copper bar having a high mass is located at a part of the rotor 1 in the circumferential direction, same effect as providing a balance weight at an end of the rotor 1 is attained. In other words, the work for providing a new balance weight can be eliminated and a balance weight can be provided easily without requiring any independent fixing jig or unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction motor for a compressor, and more particularly to a rotor capable of easily adjusting a rotor imbalance.

[0002]

2. Description of the Related Art In a compressor in which an induction motor and a scroll are integrally sealed in a container, the scroll rotates in a dynamically eccentric state. Therefore, a balance weight is provided at an end ring end of a cage rotor of the induction motor. Have been.

[0003]

In the prior art, since a balance weight is newly attached to the end face of the end ring, the number of parts is increased, and a separate mounting jig or device is required, which causes a problem in cost.

An object of the present invention is to provide a cage rotor in which a balance weight can be easily provided without a separate device.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cage rotor in which a secondary conductor consisting of a bar and an end ring is formed on a rotor core having a plurality of rotor slots, wherein the secondary conductor is made of copper and aluminum. And the axial length of at least one copper bar is made longer than the axial length of the other copper bars.

By making at least one copper bar of the rotor longer than the other copper bars and casting the copper bar by aluminum die casting, the length of the copper bar portion becomes larger than the other bars, and the balance is increased. The same action as the weight is obtained. As a result, the work of newly providing a balance weight can be eliminated, and the balance weight can be easily provided without the need for a separate mounting jig or device.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIGS.
This will be described with reference to FIG.

FIG. 1 shows the structure of a squirrel-cage rotor according to an embodiment of the present invention, and FIG. 2 shows the cross-sectional structure taken along the line AA 'of FIG.

In FIG. 1 and FIG. 2, the rotor 1 is provided with a rotor core 4 having a fully closed slot 3 on a shaft 2, and further in the fully closed slot 3, copper bars 5 and 6A, 6B, 6C are provided. A copper conductor 6 is inserted and connected to the end ring 7 (7A, 7B) by aluminum die casting to form a secondary conductor.

Here, the copper bar 6 (6A, 6B, 6C)
As shown in FIG. 2, the cross-sectional structure taken along the line AA ′ in FIG. 1 is longer than the copper bar 5 in the axial direction.

As a result, since the copper bar having a large mass is provided at a part of the circumferential position of the rotor 1, the same effect as when the balance weight is provided at the end of the rotor 1 can be obtained. That is, the operation of newly providing a balance weight can be eliminated, and the balance weight can be easily provided without requiring a separate mounting jig or device.

[0012]

According to the present invention, at least one of the copper bars of the rotor is made longer than the other copper bars, and the copper bar is cast by aluminum die-casting, so that the elongated copper bar portion becomes the other bar. The weight is larger than that of, and the same action as the balance weight can be obtained. As a result, the work of newly providing a balance weight can be eliminated, and the balance weight can be easily provided without the need for a separate mounting jig or device.

[Brief description of the drawings]

FIG. 1 is a perspective view of a cage rotor according to one embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA ′ of the squirrel-cage rotor according to one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotor, 2 ... Shaft, 3 ... Fully closed slot, 4 ... Rotor core, 5 ... Copper bar, 6 ... Copper bar longer than copper bar 5 in the axial direction, 7 ... End ring.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Mikami 7-2-1, Omika-cho, Hitachi City, Ibaraki Pref. Hitachi, Ltd. Power and Electricity Development Division (72) Inventor Mika Takahashi Hitachi, Ibaraki Prefecture 7-2-1, Omikacho Hitachi Power Systems Co., Ltd. (72) Inventor Shoji Senoo 7-1-1 Higashi Narashino, Narashino City, Chiba Prefecture Hitachi, Ltd. Industrial Equipment Division (72) Inventor Kazuo Sato 7-1-1 Higashi Narashino, Narashino City, Chiba Prefecture Within the Industrial Equipment Division, Hitachi, Ltd.

Claims (1)

[Claims] 1. A cage rotor in which a secondary conductor composed of a bar and an end ring is formed on a rotor core having a plurality of rotor slots, wherein the secondary conductor is made of copper and aluminum, A cage rotor, wherein the length of one copper in the axial direction is longer than the length of the other copper in the axial direction.