JPH114556A - Motor rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor with mounting structure of a rotor core and a rotor shaft in a motor, in which propagation of oscillation and noises is prevented. SOLUTION: A rotor core 2 has an inserting hole 2a at its center for inserting a rotor shaft 3. The inserting hole 2a has opposite U-shaped grooves 2b along an inner wall in an axial direction, while the rotor shaft 3 has a flat part 3a opposite to the groove 2b at an outer surrounding part thereof in the axial direction. In addition, a cushion member 5 made of rubber with hardness of 40 deg. to 60 deg. is applied and formed between the rotor core 2 and the rotor shaft 3 when the rotor core 2 is mounted on the rotor shaft 3.

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 electric motor, and more particularly to a structure for mounting a rotor core and a rotating shaft.

[0002]

2. Description of the Related Art FIG. 3 is a sectional view showing an example of a conventional motor rotor. Conventionally, a rotor 1 of an electric motor has a through hole 2a formed in the center of a rotor core 2, and a rotary shaft 3 is inserted into the through hole 2a. Was fixed by caulking 2z.

Alternatively, a through hole 2 is formed at the center of the rotor core 2.
a was formed, and a knurling process was applied to a mounting portion of the rotating shaft 3 (not shown), and the rotating shaft 3 was press-fitted into the insertion hole 2a and fixed.

In this case, a vibration isolating member such as a spring or a sheet is mounted between the bearing and the bracket for vibration isolation, but there is no vibration isolating member between the rotor core 2 and the rotating shaft 3. However, the vibration in the thrust direction of the rotor 1 is transmitted to the fan blades via the rotary shaft 3 to generate noise, which is a problem.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned conventional problems, and has been made in consideration of the above problem. When a rotor core and a rotating shaft of an electric motor are mounted, the rotation of the electric motor is prevented from transmitting vibration and noise. It is intended to provide children.

[0006]

In order to achieve the above object, in a rotor of an electric motor having a rotary shaft mounted in a through hole formed at the center of a rotor core, an inner peripheral wall of the through hole has a shaft. Along with forming a substantially U-shaped groove along the direction, a flat portion facing the groove is formed in the axial direction of the outer peripheral portion of the rotating shaft, and between the rotor core and the rotating shaft. The rotor core is attached to the rotating shaft by filling and forming the buffer member.

The length of the flat portion of the rotating shaft is longer than the length of the central portion of the rotor core.

[0008] Further, the length of the buffer member is formed to be longer than the length of the flat portion of the rotating shaft.

[0009] Further, at both ends of a central portion of the rotor core, cylindrical portions are formed by the cushioning member. On the other hand, the material of the buffer member is rubber. Then, the hardness of the rubber is set to be from 40 ° to 60 °.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In a rotor of a motor in which a rotary shaft is mounted in an insertion hole formed at the center of a rotor core, a substantially U-shaped groove is formed in the inner peripheral wall of the insertion hole along the axial direction. By forming a flat portion facing the groove in the axial direction of the outer peripheral portion of the rotating shaft, between the rotor core and the rotating shaft, by filling and forming a buffer member, The rotor core is attached to the rotating shaft. With this configuration, transmission of vibration and noise between the rotor core of the electric motor and the rotating shaft is prevented.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the accompanying drawings. Here, the same reference numerals are used for the same parts as in the conventional example.

FIG. 1 is a cross-sectional view of an embodiment of a rotor of a motor according to the present invention, and FIG. 2 is a cross-sectional view corresponding to a cross section taken along AA ′ of FIG.

At the center of the rotor core 2, an insertion hole 2a through which the rotating shaft 3 is inserted is formed, and a substantially U-shaped groove 2b is formed on the inner peripheral wall thereof along the axial direction. At the same time, a flat portion 3a facing the groove 2b is formed in the axial direction of the outer peripheral portion of the rotating shaft 3.

Thereafter, a cushioning member 5 made of rubber and having a hardness of 40 ° to 60 ° is filled between the rotor core 2 and the rotating shaft 3 to form the rotor core 2. Attached to the rotating shaft 3.

The length of the flat portion 3a of the rotating shaft 3 is made longer than the length of the central portion of the rotor core 2.

Further, the length of the buffer member 5 is formed to be longer than the length of the flat portion 3a of the rotating shaft 3.

Further, at both ends of the central portion of the rotor core 2, cylindrical portions 5a formed by the buffer members 5 are formed.

Here, the effects of the present invention will be described.
As described above, between the rotor core 2 and the rotating shaft 3, the cushioning member 5 made of rubber and having a hardness of 40 ° to 60 ° is filled and molded between the rotor core 2 and the rotating shaft 3. Although the rotating shaft 3 rotates integrally, the vibration of the rotor core 2 becomes difficult to be transmitted to the rotor 3 because the buffer member 5 is made of rubber. When the hardness of the rubber is smaller than the above value, a sufficient driving force cannot be obtained in terms of strength. On the other hand, when the value is larger than the above value, the vibration damping effect is obtained although the strength is sufficient. It becomes difficult.

The length of the flat portion 3a of the rotating shaft 3 is formed to be longer than the length of the central portion of the rotor core 2, and the length of the buffer member 5 is reduced by the flat portion of the rotating shaft 3. 3
a, and the cylindrical portions 5a of the cushioning members 5 are formed at both ends of the central portion of the rotor core 2. Therefore, between the rotor core 2 and the rotating shaft 3, Since the buffer member 5 is filled without gaps, it is possible to obtain an anti-vibration effect on all portions where vibration is transmitted.

For this reason, the transmission of the thrust vibration through the rotor 1 can be prevented.

[0021]

As described above, according to the present invention, in a rotor of a motor in which a rotary shaft is attached to an insertion hole formed at the center of a rotor core, an inner peripheral wall of the insertion hole extends along an axial direction. And a flat portion facing the groove is formed in an axial direction of an outer peripheral portion of the rotating shaft, and a cushioning member is provided between the rotor core and the rotating shaft. , The rotor core is attached to the rotating shaft. As a result, it is possible to provide a motor rotor in which transmission of vibration and noise is prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a rotor of an electric motor according to the present invention.

FIG. 2 is a sectional view corresponding to AA 'in FIG.

FIG. 3 is a sectional view showing an example of a rotor of a conventional electric motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor 2 Rotor iron core 2a Insertion hole 2b Groove 3 Rotation shaft 3a Flat part 5 Buffer member 5a Cylindrical part

Claims (6)

[Claims] 1. A rotor of a motor in which a rotating shaft is attached to an insertion hole formed at the center of a rotor core, wherein a substantially U-shaped groove faces an inner peripheral wall of the insertion hole along an axial direction. And forming a flat portion facing the groove in the axial direction of the outer peripheral portion of the rotating shaft, and filling and shaping a cushioning member between the rotor core and the rotating shaft. A rotor for an electric motor, wherein a child core is attached to the rotating shaft. 2. The rotor for an electric motor according to claim 1, wherein a length of the flat portion of the rotating shaft is longer than a length of a central portion of the rotor core. 3. The rotor for an electric motor according to claim 2, wherein a length of said buffer member is formed longer than a length of a flat portion of said rotary shaft. 4. A rotor for an electric motor according to claim 3, wherein cylindrical portions are formed at both ends of a central portion of said rotor core by said buffer member. 5. The rotor for an electric motor according to claim 1, wherein the material of the cushioning member is rubber. 6. The rotor for an electric motor according to claim 5, wherein the rubber has a hardness of 40 ° to 60 °.