JPH08154366A - Induction motor rotor - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the efficiency in the high-speed rotation range of the rotor of an induction motor used for air conditioning equipment, etc., and to reduce costs by sharing dies. [Composition] The secondary resistance of the motor can be reduced by insert die-casting the metal 3 having a low electric resistance with the aluminum 2 on the end surface of the laminated rotor iron core 1, and the efficiency can be improved in the high speed rotation range. Moreover, since the motor characteristics can be changed by sharing the mold, the cost can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of an induction motor used in air conditioners and the like.

[0002]

2. Description of the Related Art In recent years, comfort has been demanded in the air-conditioning industry, and in such a trend, there has been a demand for higher efficiency in the high-speed rotation range of a motor, and there is a wide variety of needs for fan performance. In order to respond, various motor characteristics are required.

There is a method of changing the secondary resistance of the motor in order to change the characteristics of the motor, and the secondary resistance of the motor may be reduced in order to rotate the motor at a high speed.

The rotor of the conventional induction motor will be described below. FIG. 5 is an explanatory view of a rotor of an induction motor configured by a conventional aluminum die casting, and FIG. 6 is an enlarged sectional view of a rotor iron core end surface portion of the rotor of the conventional induction motor. In FIGS. 5 and 6, 1 is a rotor iron core and 2 is aluminum. The conventional rotor shown in the figure is constructed by die-casting a rotor core made of laminated iron plates with a die.

In the above structure, the secondary resistance of the motor is changed depending on the amount of die-cast aluminum.

[0006]

However, the above-mentioned conventional configuration has the following problems.

In the method of reducing the secondary resistance of the motor by the amount of aluminum die-cast, the cross-sectional area of the end ring of the die-cast rotor must be increased because the conductivity of aluminum is fixed. As the cross-sectional area increases, the size of the rotor, and thus the size of the motor itself, also increases, so there is a limit to improving efficiency in the high-speed rotation range with this method. In addition, a large number of molds are required for various motor characteristics, resulting in high cost in terms of mold cost and man-hours for changing sets.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a rotor for an induction motor, which realizes efficiency improvement in a high speed rotation range at low cost.

[0009]

To achieve this object, the present invention fixes a metal having an electric resistance of 6.5 [μ · Ω · cm] or less on an end face of laminated rotor iron cores, It has a structure of insert die casting with aluminum.

[0010]

The secondary resistance of the motor can be lowered and the efficiency can be improved in the high speed rotation range by insert die-casting the metal having low electric resistance. Further, since the secondary resistance of the motor can be freely changed by the metal to be inserted, the characteristics of the motor can be changed by sharing the mold.

[0011]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram of a rotor of an induction motor according to an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of the rotor iron core end surface portion of the rotor of the induction motor in the embodiment. FIG. 3 is a perspective view of a metal having an electric resistance of 6.5 [μΩΩcm] or less (hereinafter referred to as a metal having a low electric resistance) fixed to the rotor of this embodiment. Using.
Further, FIG. 4 is a view showing an assembled state of a rotor iron core and a metal having a low electric resistance before aluminum die casting.

1, FIG. 2, FIG. 3, and FIG. 4, 3 is a metal having a low electric resistance, 1 is a rotor iron core, and A is a groove for fixing a metal having a low electric resistance provided in the rotor iron core. 2 is aluminum.

In the rotor of the induction motor of the present embodiment, the convex portion of the metal 3 having a low electric resistance, which is a cylinder having a step on the outer peripheral surface, is provided on the axial end surface of the rotor iron core 1 in which iron plates are laminated. A groove A for fixing is provided, a metal 3 having a low electric resistance is fixed in the groove A, and insert die casting with aluminum 2 is performed.

With the above structure, the metal 3 having a low electric resistance and the aluminum 2 are electrically connected, and the secondary resistance of the motor can be reduced. Moreover, the secondary resistance of the motor can be freely changed by using a common mold.

[0016]

As described above, according to the rotor of the induction motor of the present invention, a metal having a low electric resistance is fixed to the end surface of the laminated rotor iron cores, and the die is cast by aluminum to achieve a high speed motor. It is possible to improve efficiency in the rotation range. Further, the secondary resistance of the motor can be freely changed by sharing the mold, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a rotor of an induction motor according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a rotor iron core end surface portion of a rotor according to an embodiment of the present invention.

FIG. 3 is a perspective view of a metal having a low electric resistance fixed to the rotor of this embodiment.

FIG. 4 is a diagram showing an assembled state of a rotor iron core and a metal having low electric resistance before being die-cast with aluminum.

FIG. 5 is an explanatory view of a rotor of a conventional induction motor.

FIG. 6 is an enlarged cross-sectional view of a rotor iron core end surface portion of a conventional induction motor rotor.

[Explanation of symbols]

 1 Rotor iron core 2 Aluminum 3 Metal with low electrical resistance A Fixed groove

Claims (2)

[Claims] 1. An induction motor characterized in that a metal having an electric resistance of 6.5 [μ · Ω · cm] or less is fixed to an end surface of laminated rotor iron cores, and insert die casting is performed with aluminum. Rotor. 2. The rotor of an induction motor according to claim 1, wherein copper is used as the metal.