JPH04248355A - Rotor of induction motor - Google Patents

Abstract

PURPOSE:To uniform magnetic flux at a slot, lower the substantial density of magnetic flux and improve efficiency in an induction motor equipped with a rotor with a laminated core formed by laminating thin iron sheets. CONSTITUTION:A plurality of U-shaped slots 3 having openings 2 at the outer peripheral edge are provided on the outer periphery of disk-shaped thin iron plate 1, and a plurality of thin iron plates 1 are laminated for forming a laminated iron core. By inserting a flat iron conductor 7 into the slot 3 of the laminated iron core, the core area opposed to the air gap is increased, by which the magnetic flux of air gap is made uniform, substantial magnetic flux density is lowered, and a rotor of induction motor having a high efficiency can be obtained.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor for an induction motor which has a reduced effective magnetic flux density and improved efficiency.

0002

2. Description of the Related Art The rotor of a conventional induction motor will be explained below. As shown in FIGS. 4 and 5, a plurality of U-shaped slots 3 having an opening 2 at the outer peripheral end are provided on the outer periphery of a disc-shaped book iron plate 1, and a plurality of book iron plates 1 are stacked. A laminated iron core 4 is formed.

[0003] During this stacking, the slots 3 are skewed at a predetermined inclination. A conductor 5 made of copper or aluminum is inserted into the slot 3, and both ends of the conductor 5 are connected to an end ring 6, which is a ring-shaped conductor, by caulking or ultrasonic bonding on both end surfaces of the laminated core 4.

The flow of magnetic flux in the rotor of the induction motor constructed as described above is as shown by the arrows in FIG.

[0005]

[Problems to be Solved by the Invention] However, in the above-mentioned conventional configuration, since the material of the conductor is copper or aluminum, the area of the iron core facing the air gap is reduced, so the effective magnetic flux density of the air gap increases and efficiency increases. There was a problem in that the value decreased.

The present invention solves the above-mentioned conventional problems, and aims to provide a highly efficient rotor for an induction motor by making the magnetic flux uniform and reducing the actual magnetic flux density.

[0007]

SUMMARY OF THE INVENTION In order to achieve this object, the rotor of an induction motor of the present invention has a structure in which flat iron conductors are disposed within slots of a laminated core.

[0008]

[Operation] With this configuration, the area of the iron core facing the air gap increases, and the magnetic flux in the air gap becomes uniform.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 to 3 showing an embodiment of the present invention, parts that are the same as those in the conventional example are given the same numbers and their explanations will be omitted. As shown in FIGS. 1 and 2, a flat iron conductor 7 is inserted into a slot 3.

Since the material of the conductor 7 is iron, the flow of magnetic flux in the rotor of the induction motor constructed as described above is as shown in FIG.
Since the area of the iron core facing the air gap increases as shown in FIG.

As described above, according to this embodiment, by arranging flat iron conductors in the slots of the laminated core, the magnetic flux in the air gap is made uniform, the actual magnetic flux density is reduced, and the efficiency is improved. gets better.

Note that the rotor of the induction motor of this embodiment is as follows:
It can be applied to either three-phase or single-phase induction motors.

[0014]

[Effects of the Invention] As is clear from the description of the embodiments described above, the present invention has a plurality of U-shaped slots each having an opening at the outer peripheral end formed of a disc-shaped thin iron plate. By arranging iron conductors in the slots of the laminated core, the magnetic flux in the air gap is made uniform, the actual magnetic flux density is reduced, and an excellent induction motor rotor with high efficiency can be realized.

[Brief explanation of the drawing]

FIG. 1 is a partial plan view showing a state in which conductors are inserted into a thin iron plate of a rotor of an induction motor according to an embodiment of the present invention.

[Fig. 2] A schematic front view showing the concept of the structure of the laminated core of the rotor of an induction motor according to one embodiment.

FIG. 3 is an explanatory diagram showing the flow state of magnetic flux in the slots of the rotor of the induction motor in one embodiment.

[Figure 4] A partial plan view showing a state in which conductors are inserted into the thin iron plate of the rotor of a conventional induction motor.

[Fig. 5] A schematic front view showing the concept of the structure of the laminated core of the rotor of a conventional induction motor.

[Fig. 6] An explanatory diagram showing the flow state of magnetic flux in the rotor slot of a conventional induction motor.

[Explanation of symbols]

1 Thin iron plate 3 Slot 4 Laminated iron core 7 Conductor

Claims (1)

[Claims] 1. A rotor with a laminated iron core formed by stacking disk-shaped thin iron plates each having a plurality of U-shaped slots each having an opening on the outer periphery, wherein a plurality of U-shaped slots each having an opening at the outer periphery of the core are laminated. The rotor of an induction motor has a flat iron conductor arranged in the rotor.