CN217216128U

CN217216128U - Rotor for motor

Info

Publication number: CN217216128U
Application number: CN202220699647.8U
Authority: CN
Inventors: 小林亚希子; 柳生泰秀
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2022-03-29
Filing date: 2022-03-29
Publication date: 2022-08-16
Anticipated expiration: 2032-03-29

Abstract

The utility model provides a rotor that motor was used. The rotor for the motor comprises a rotor core formed by laminating a plurality of steel plates and a shaft pressed and fixed in a shaft hole of the rotor core, wherein at least one of a key groove and a notch key is formed on the inner circumferential surface of the rotor core, and the plurality of steel plates are welded and connected into a whole at a specified position in an area of the inner circumferential surface of the rotor core, the surface pressure of which is increased due to the press-in of the shaft. With this structure, the rotor core and the shaft can be firmly coupled to each other.

Description

Rotor for motor

Technical Field

The utility model relates to a rotor that motor was used.

Background

In general, in a rotor for a motor, a shaft is fixed to a shaft hole of a rotor core formed by stacking a plurality of steel plates by shrink fitting. Outer diameter portions of a plurality of steel plates constituting the rotor core are welded to each other, but inner diameter portions of each other are not welded. Therefore, in a state where the shaft is press-fitted into the shaft hole of the rotor core by shrink fitting, the plurality of steel plates constituting the rotor core are easily bent by a fastening load generated by the press-fitting. Therefore, there is a possibility that the coupling force between the rotor core and the shaft is weakened.

SUMMERY OF THE UTILITY MODEL

In view of the above, an object of the present invention is to provide a rotor for a motor, which can be firmly coupled between a rotor core and a shaft.

As a solution to the above-described problems, the present invention provides a rotor for a motor, including a rotor core formed by stacking a plurality of steel plates, and a shaft pressed into and fixed to a shaft hole of the rotor core, wherein at least one of a key groove and a notch key is formed on an inner peripheral surface of the rotor core, the rotor comprising: the plurality of steel plates are welded and integrated at predetermined portions in a region of the inner peripheral surface of the rotor core where the surface pressure is increased by the press-fitting of the shaft.

The utility model discloses an advantage of above-mentioned rotor for motor lies in, because the polylith steel sheet that constitutes rotor core is in rotor core's inner peripheral surface (i.e., rotor core's internal diameter side) welded together, so, rotor core's the thick sum of polylith steel sheet thickness for the polylith steel sheet thickness that fuses, therefore, compare with the structure that the internal diameter side of polylith steel sheet was not welded together, rotor core's cross-section secondary torque increases to the buckling resistance of steel sheet increases. As a result, the plurality of steel plates constituting the rotor core can be prevented from buckling due to a fastening load generated when the shaft is pressed into the shaft hole of the rotor core, and the rotor core and the shaft can be firmly coupled to each other.

In the rotor for a motor according to the present invention, it is preferable that a groove extending in the axial direction of the rotor core is formed at a predetermined position in the region where the surface pressure increases, and the plurality of steel plates are integrally connected by welding the inner side of the groove. With this structure, the plurality of steel plates can be easily integrated by welding the inner sides of the grooves.

Drawings

Fig. 1 is a perspective view showing a part of a rotor core of a rotor for a motor according to a first embodiment of the present invention.

Fig. 2 is a plan view showing a part of the rotor.

Fig. 3 is a plan view showing a part of a rotor core of a rotor for a motor according to a second embodiment of the present invention.

Detailed Description

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

< first embodiment >

Fig. 1 is a perspective view showing a part of a rotor core 2 of a rotor for a motor according to the present embodiment. As shown in fig. 1, a rotor 1 includes a rotor core 2 and a shaft 3.

Fig. 2 is a plan view showing a part of the rotor 1. As shown in fig. 2, the rotor core 2 is formed by press-working a steel plate 5 having a predetermined thickness into a predetermined shape, and stacking a plurality of the steel plates 5 after the press-working.

As shown in fig. 1 and 2, a shaft hole 21 is formed in the center of the rotor core 2. The shaft 3 is press-fitted and fixed into the shaft hole 21 of the rotor core 2. That is, after the shrink fitting, the shaft 3 is press-fitted into the shaft hole 21 of the rotor core 2.

A key groove 22 is formed in a predetermined region in the circumferential direction of the inner circumferential surface of the rotor core 2. At the same time, a key groove 31 is formed in a predetermined region in the circumferential direction of the outer peripheral surface of the shaft 3. By arranging the shaft 3 such that the key groove 22 of the rotor core 2 and the key groove 31 of the shaft 3 face each other, a key insertion hole can be formed. Then, by inserting the key 4 into the key insertion hole, relative rotation between the rotor core 2 and the shaft 3 can be reliably prevented.

In the present embodiment, a plurality of steel plates 5 are welded and integrated at predetermined portions in a region of the inner peripheral surface of the rotor core 2 where the surface pressure increases due to the press-fitting of the shaft 3 (i.e., in the vicinity of the key grooves 22, as indicated by one-dot chain lines in fig. 2). Specifically, in the region where the surface pressure rises, the grooves 23 extending in the axial direction of the rotor core 2 are formed over the entire axial region. The plurality of steel plates 5 are integrally connected by welding the inner sides of the grooves 23. Fig. 2 shows weld mark 6 after the inside of groove 23 is welded.

Next, the coupling between the rotor core 2 and the shaft 3 will be described.

First, the shaft 3 is press-fitted into the shaft hole 21 of the rotor core 2 by shrink fitting. In a state where the shaft 3 is press-fitted into the shaft hole 21 of the rotor core 2 by shrink fitting, the plurality of steel plates 5 constituting the rotor core 2 are likely to be buckled by a fastening load generated by press-fitting the shaft 3.

In contrast, in the present embodiment, as described above, the grooves 23 extending in the axial direction of the rotor core 2 over the entire area are formed in the area of the inner peripheral surface of the rotor core 2 where the surface pressure is increased by the press-fitting of the shaft 3, and the plurality of steel plates 5 constituting the rotor core 2 are integrally connected, that is, welded together on the inner diameter side by welding the inner sides of the grooves 23.

Since the plurality of steel plates 5 constituting the rotor core 2 are integrally connected, the plate thickness h of the rotor core 2 is the sum of the plate thicknesses of the plurality of steel plates 5. In this case, the sectional secondary torque I of the rotor core 2 is: i ═ bh ³ And/12, wherein b is the width dimension, and the plate thickness h is the sum of the plate thicknesses of the plurality of steel plates 5. Therefore, the sectional secondary torque I increases due to the increase in the plate thickness h, as compared with a structure in which a plurality of steel plates 5 are not integrally connected, and therefore the buckling resistance of the steel plates 5 increases.

As a result, the plurality of steel plates 5 constituting the rotor core 2 can be prevented from buckling due to a fastening load generated by press-fitting the shaft 3 into the shaft hole 21 of the rotor core 2, and the rotor core 2 and the shaft 3 can be firmly coupled to each other.

< second embodiment >

Fig. 3 is a plan view showing a part of the rotor core 2 of the rotor 1 for a motor according to the present embodiment. In the present embodiment, a plurality of notch keys 24 are formed at predetermined intervals in the circumferential direction on the inner circumferential surface of the rotor core 2. Further, on the inner peripheral surface of the rotor core 2, grooves 23 extending in the axial direction of the rotor core 2 over the entire axial region are formed in regions where the surface pressure is increased by press-fitting the shaft 3, that is, between the adjacent notch keys 24 (as indicated by chain lines in fig. 3). The inner sides of the grooves 23 are welded, and a plurality of steel plates constituting the rotor core 2 are integrally connected on the inner diameter side of the rotor core 2.

Other configurations of the rotor 1 of this embodiment are the same as those of the first embodiment, and detailed description of other portions is omitted here.

The plurality of notch keys 24 are provided to disperse the surface pressure due to the fastening load generated by the press-fitting of the shaft 3. Since the plurality of notch keys 24 are formed, the surface pressure of the area (shown by one-dot chain line in fig. 3) between the notch keys 24 adjacent in the circumferential direction increases.

In contrast, in the present embodiment, as described above, the plurality of steel plates 5 constituting the rotor core 2 are welded and integrated on the inner diameter side of the rotor core 2 by forming the grooves 23 in the regions between the notch keys 24 adjacent in the circumferential direction and welding the insides of the grooves 23. Accordingly, the thickness h of the rotor core 2 is the sum of the thicknesses of the plurality of steel plates 5. Therefore, as compared with a structure in which a plurality of steel plates 5 are not welded together on the inner diameter side of the rotor core 2, the sectional secondary torque I of the rotor core 2 increases, and the buckling resistance of the steel plates 5 increases.

The present invention is not limited to the contents described in the first and second embodiments, and various applications and modifications can be made without departing from the technical scope of the present invention.

For example, in each of the above embodiments, the groove 23 extending in the axial direction is formed in the region where the surface pressure is increased by press-fitting the shaft 3 in the inner peripheral surface of the rotor core 2, and the plurality of steel plates are integrally connected by welding the inner side of the groove 23. However, the present invention is not limited to this, and other welding structures may be employed as long as the plurality of steel plates 5 constituting the rotor core 2 are welded and integrated at predetermined portions in the region where the surface pressure increases due to the press-fitting of the shaft 3 on the inner circumferential surface of the rotor core 2.

In addition, the key groove 22 and the notch key 24 may be formed on the inner circumferential surface of the rotor core 2.

Claims

1. A rotor for a motor, comprising a rotor core formed by laminating a plurality of steel plates, and a shaft press-fitted and fixed to a shaft hole of the rotor core, wherein at least one of a key groove and a notch key is formed on an inner circumferential surface of the rotor core, characterized in that:

the plurality of steel plates are welded and integrated at predetermined portions in a region of the inner peripheral surface of the rotor core where the surface pressure is increased by the press-fitting of the shaft.

2. A rotor for a motor according to claim 1, wherein:

a groove extending in the axial direction of the rotor core is formed at a predetermined portion in the region where the surface pressure is increased, and the plurality of steel plates are integrally connected by welding the inside of the groove.