JPH05168183A - Vibration isolator of motor - Google Patents

Abstract

PURPOSE:To effectively absorb vibration by making time vibration generated by a motor rotating hard to be transmitted to a rotor shaft. CONSTITUTION:This vibration isolator is equipped with a circular outer rotor core 2, where a permanent magnet 1 is fixed to the periphery, and an inner rotor core 4, which is fixed to a rotor shaft 3, and the inner rotor core 4 holds the outer rotor core 2 through a plate spring 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor vibration isolator for a brushless fan motor used in room air conditioners and water heaters.

[0002]

2. Description of the Related Art In recent years, a fan motor of PWM control drive for controlling a motor rotation speed cannot sufficiently suppress fan resonance, and an inexpensive and more effective countermeasure is required.

A conventional fan motor will be described with reference to FIG. As shown in the figure, the motor 11 is composed of a stator 12 and a rotor 13, a rotor 13 is provided with a permanent magnet 14, and is integrally fixed to a rotor shaft 15.

The rotor 13 is rotatably mounted on the motor frame 11a, on which the stator 12 is disposed, via a bearing 16. Then, when fixing the fan 17 to the end of the rotor shaft 15, the rubber cushion 18 is sandwiched from both sides by a sandwich structure and fixed by the nut 19.
The noise generated by the resonance of the fan 17 is reduced.

[0005]

In such a conventional fan motor configuration, when the motor 11 rotates, the motor 11 generates a rotational force between the permanent magnet 14 of the rotor 13 and the stator 12. Therefore, the permanent magnet 1 of the rotor 13
Since the rotor shaft 15 and the permanent magnet 14 are directly and integrally fixed by the rotor core, the vibration caused by the gogging force or the like generated in No. 4 is transmitted to the rotor shaft 15 with almost no damping. It was

The present invention solves the above problems, and provides a vibration damping device for a motor, which makes it difficult to transmit the vibration generated by the rotation of the motor to the rotor shaft and effectively absorb the vibration. The purpose is to do.

[0007]

In order to achieve the above object, a vibration isolator according to the present invention comprises an annular outer rotor core having a permanent magnet fixed to its outer periphery and an inner rotor core fixed to a rotor shaft. The outer rotor core is held by the inner rotor core via a leaf spring.

[0008]

With the above-described structure, the present invention prevents the leaf spring from absorbing the vibration and transmitting the vibration to the rotor shaft even if the motor rotates and the permanent magnet vibrates due to fluctuations in the gogging force. Will be done.

[0009]

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. As shown in the figure, the permanent magnet 1 is mounted on the outer periphery of an annular outer rotor core 2, and the inner rotor core 4 is fixed to the motor shaft 3. Further, a plurality of locking portions 2a are formed in the inner diameter of the outer rotor core 2 in the radial direction, and a plurality of locking portions 2a formed on the outer rotor core 2 are formed on the outer circumference of the inner rotor core 4. Multiple locking parts 4 at the position
a is formed.

Then, the plate member is bent along the outer periphery of the inner rotor core 4 so as to come into contact with the inner diameter portion of the outer rotor core 2, and two corners are projected to form a substantially butterfly-shaped spring member. The leaf spring 5 is formed in the partition formed by the inner rotor core 4 and the outer rotor core 2 and is partitioned by the locking portions 2a and 4a. The locking portions 2a and 4a cause the leaf spring 5 to rotate in the rotational direction. The rotor 6 is held while being prevented from moving, and the outer rotor core 2 is held by the inner rotor core 4 via the leaf spring 5 to form the rotor 6.

In the above structure, when the rotor 6 rotates and vibrations occur in the permanent magnet 1 due to fluctuations in the gogging force, vibrations 7 generated in the outer rotor core 2 integrally fixed to the permanent magnet 1 generate the rotor shaft 3. The inner rotor core 4 fixed to the inner peripheral surface of the leaf spring 5 is elastically deformed by a restoring force as shown by an arrow 8 and relatively changes, so that the vibration is effectively absorbed.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to FIG. The second embodiment is the first
It is a modification of the shape of the spring plate in the embodiment,
As shown in the figure, contact ends 6 contacting the outer rotor core 2 are provided at both ends of a portion contacting the outer peripheral portion of the inner rotor core 4.
The leaf spring 5a is formed by forming a. And
The effect of the leaf spring 5a is the same as that of the first embodiment.

[0013]

As is apparent from the above embodiments, according to the present invention, the outer rotor core having the permanent magnet mounted on the outer periphery is held by the inner rotor core fixed to the rotor shaft via the leaf spring. Therefore, unstable factors such as thermal deformation and deterioration over time due to the use of rubber or the like as the vibration absorbing means can be eliminated, and a vibration damping device for a motor having a simple structure, low cost, and high reliability can be provided.

[Brief description of drawings]

FIG. 1 is a front view of a rotor according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway front view showing a holding state of a leaf spring of the rotor of the first embodiment.

FIG. 3 is a partially cutaway front view showing a holding state of a leaf spring of the rotor of the second embodiment.

FIG. 4 is a sectional view showing the configuration of a conventional fan motor.

[Explanation of symbols]

 1 permanent magnet 2 outer rotor core 3 rotor shaft 4 inner rotor core 5 leaf spring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Fumitoshi Yamashita, 1006 Kadoma, Kadoma City, Osaka Prefecture, Matsushita Electric Industrial Co., Ltd. (72) Akihiko Watanabe, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] 1. An outer rotor core having an annular shape having a permanent magnet fixed to the outer periphery thereof, and an inner rotor core fixed to a rotor shaft, wherein the outer rotor core is held by a spring member. Anti-vibration device for motors.