JP2583279Y2 - Rotating electric machine rotor - Google Patents

Description

[Detailed description of the invention]

[0101]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for fixing a rotor core of an induction motor rotating at high speed.

[0092]

2. Description of the Related Art Conventionally, a rotor is generally fixed in an axial direction by die-casting a rotor bar on a slot provided in a laminated core. Also, as another axial fixing method,
There is a method in which a stator core is manufactured by winding molding, and notches provided at a plurality of locations on the outer periphery of the stator core are fixed by laser welding in an axial direction (for example, Japanese Patent Application Laid-Open No. 2-95147).

[0093]

However, in the conventional method, the strength of Al die-casting is not sufficient during high-speed rotation, and a gap is formed between the cores due to bending of the shaft. Bearing vibration due to deterioration may increase, which may result in inoperability.
Furthermore, since the bending rigidity is low, the bending natural frequency is low,
There is a problem that the rated rotation speed cannot be increased. Further, in order to reinforce the strength in the axial direction, for example, Japanese Unexamined Patent Publication No.
If the technology described in Japanese Patent Application Publication No. 7 is applied to a rotor constituted by a laminated core, the welding location is on the outer diameter side and the welding direction is axial, which causes torque ripple and lowers performance. Therefore, an object of the present invention is to provide a rotor fixing structure capable of obtaining sufficient axial bending strength without deteriorating performance.

[0093]

Means for Solving the Problems Cores 2 laminated in the axial direction
1 and a rotor of a rotary electric machine composed of a rotor bar 5 in which a good conductor is die-cast on an axial slot 3 provided on the core 21.
The cores 22 whose outer diameters are smaller by 1 than the laser welding allowance are overlapped, and the blocks 2a... 2e which are spot or flash welded in the axial direction are stacked in the axial direction with the blocks 2a. The laser welding portions 3a to 3d to be laser-welded are integrated to form a laminated core assembly, and the rotor bar 5 is die-cast on the assembly to form a rotor.

[0056]

According to the above-mentioned means, the blocks are connected with bending rigidity, so that there is no axial unevenness on the gap surface.

[0086]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1A is a sectional view showing an embodiment of the present invention, FIG.
1B is a side sectional view showing a block alone, FIG. 1C is a side sectional view showing an AA section in FIG. 1A, and FIG. 1D is a partial sectional view showing a joint. The shaft 1 has a laminated core 21
Are axially divided and shrink-fitted like a plurality of blocks 2a... 2e. Each block 2a... 2e is formed by laminating holes for fitting the shaft 1 on the inner diameter side and several cores 21 punched out slots 3 for the rotor bar on the outer diameter side.
The cores 22 each having a core outer diameter smaller than the gap diameter by the welding allowance are superposed one by one, and are integrally welded in the axial direction at spot welds 4a... 4g provided at a fine pitch on the circumference. The spot welds 4a... 4g may be flash-welded. The integrated blocks 2a... 2e are overlapped in the axial direction, and the circumferential grooves formed at the joints between the blocks 2a... 2e are welded as laser welds 3a. I do. The rotor bar 5 is formed by die-casting Al or the like in the slot 3 of the assembly of the laminated core. Both ends of the rotor bar 5 are connected by an end ring 6 which is die-cast at the same time.

[0099]

As described above, according to the present invention, since a block obtained by spot welding or flash welding of a laminated core is joined by laser welding to form a laminated core assembly, a gap is formed between the cores. It is possible to eliminate an increase in bearing vibration due to deterioration of the rotor balance without occurrence. In addition, as the bending rigidity is improved, the natural bending frequency of the rotor is also increased, so that the rated rotation speed can be increased. Further, since the blocks are connected by an axial spot, and the blocks are welded and connected in the circumferential direction, there is no axial unevenness on the gap surface and no torque ripple.

[Brief description of the drawings]

FIG. 1 is a sectional view and a partial side sectional view showing an embodiment of the present invention.

[Explanation of symbols]

 1 shaft 2a... 2e block 21, 22 core 3 slot 4a... 4h spot weld 5 rotor bar 6 end ring

Claims (1)

(57) [Scope of request for utility model registration] 1. A rotor of a rotary electric machine comprising a core (21) laminated in an axial direction and a rotor bar (5) obtained by die-casting a good conductor in an axial slot (3) provided in the core (21). A plurality of blocks (2a... 2e) which are formed by laminating (21), superposing a core (22) having an outer diameter smaller than that of the core (21) by a laser welding margin on both ends thereof, and spot or flash welding in the axial direction; The plurality of blocks (2a... 2e) are stacked in the axial direction, and the joints are integrated by laser welding (3a... 3d) for laser welding in the circumferential direction to form an assembly of a laminated core. A rotor for a rotating electric machine, wherein a rotor bar (5) is die-cast on a body.