JPH0297257A - Rotor of squirrel-cage induction motor - Google Patents

Abstract

PURPOSE:To shorten the length of an induction motor in its axial direction by providing a conducting part, consisting of material of specific gravity larger than that of a die-cast material, to be placed in a slot and/or in a short-circuit ring and forming a balancer. CONSTITUTION:A bar member 8, consisting of Cu with specific gravity larger than Al, has a sectional shape with the peripheral curvature almost agreeing with the curvature in an upper part bottom of a slot 2 forming a sector section, and the bar member 8, partly bringing its peripheral surface into contact with the upper part bottom and extending in the axial direction in an Al conductor 3, protrudes the one end from the slot 2 into a short-circuit ring 4. This bar member 8 is provided in the two or more slots 2 adjacent to each other, and a balancer of required weight as the total is formed by these two or more bar members 8. Since the balancer is placed in the slot or in the short-circuit ring, a rotor enables its length to be shortened in the axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a die-cast rotor for a squirrel cage induction motor having a balancer for suppressing vibration components of driven equipment.

[Conventional technology]

The electric motor that drives the air conditioner compressor has
The vibration components of the compressor are suppressed to reduce noise, and
In order to prevent the life of the motor bearing from decreasing, a balancer (balance weight) is provided on the rotor.

Figure 2 (al and (bl) shows the Aβ (aluminum) die-cast rotor of a squirrel-cage induction motor used for this type of application, where 1 is the iron core, 2 is the slot, and 3 is the rotor in the slot 2. Cast A1 conductor, 4 is Aβ short circuit ring,
Reference numeral 5 indicates a rotor shaft hole, and reference numeral 6 indicates a balancer. The balancer 6 is constructed by forming a protrusion in a part of the short-circuit ring 4 that protrudes outward in the axial direction.

This balancer 6 is an integrated balancer, and as shown in Fig. 3 (
As shown in al and (b), a separately formed balancer 7
may be attached to the shorting ring 4.

[Problem to be solved by the invention]

In this way, in conventional balancers, both the integral type 6 and the separately attached type 7, the part protrudes outward in the axial direction, so the axial length of the rotor is increased accordingly. , which prevents the compressor from becoming more compact.

The present invention has been made to solve the above problems, and an object thereof is to provide a rotor for a squirrel-cage induction motor that has a balancer but can have a shorter axial length than conventional ones. do.

[Means to solve the problem]

In order to achieve the above object, the present invention forms a balancer by incorporating a conductive part made of a material having a higher specific gravity than the die-casting material into the slot and/or the short-circuit ring.

[Effect]

In the present invention, since the balancer is located in the slot and/or in the short circuit ring, the axial length of the rotor can be shortened compared to the conventional one.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIGS. 1(a) and 1(b), reference numeral 8 denotes a bar member made of copper Cu, which has a higher specific gravity than Aβ, and has a curvature of the outer periphery.
It has a cross-sectional shape that almost matches the curvature of the upper bottom (end on the rotor surface side) of the slot 2 which has a fan-shaped cross section, and runs inside the AP conductor 3 in the axial direction with a part of the circumferential surface in contact with the upper bottom of the slot 2. It extends, and one end protrudes from the slot 2 into the Aβ shorting ring 4 . The convex members 8 are provided in a plurality of adjacent slots 2, and the plurality of bar members 8 collectively form a balancer having a required weight.

Since the outer shape of the rotor of this embodiment is the same as the outer shape of a rotor without a balancer, the rotor has a shorter axial length than the conventional rotor with a balancer.

Since the bar conductor 8 of this embodiment is a good conductor, the electrical efficiency of the induction motor is improved but not decreased.

In the above embodiment, the bar conductor 8 extends from inside the slot 2 into the shorting ring 4, but it may be configured to exist only inside the slot 2 or inside the shorting ring 4.

〔Effect of the invention〕

As explained above, the balancer is included in the rotor and/or the short-circuit ring, so the axial length of the induction motor can be reduced compared to a conventional rotor having a balancer projecting in the axial direction. Can be shortened.

[Brief explanation of drawings]

FIG. 1 (al is a half cross-sectional side view showing an embodiment of the present invention,
Fig. 1(b) is a sectional view taken along line A-A in al, Fig. 2 F8 is a side view of a half section of a conventional die-cast rotor, and Fig. 3 (al is a half cross-sectional side view of another conventional die-cast single rotor, and FIG. 3 (bl is a CC arrow shown in FIG. 3(a)) It is a perspective view. 1 - iron core, 2 - - slot, 3 - ρ to five bodies, 4 Aβ short circuit ring, 8 - bar conductor forming a balancer.

Claims (1)

[Claims] In a die-cast rotor of a squirrel-cage induction motor having a balancer for suppressing vibration components of driven equipment, a conductive part made of a material having a higher specific gravity than the die-cast material is embedded in some of the slots and/or short-circuit rings. A rotor for a squirrel-cage induction motor, characterized in that the balancer described above is formed with a rotor.