JPH05344684A - Rotor - Google Patents

Abstract

(57) [Abstract] [Purpose] To eliminate the adhesive for the sensor magnet fixed to the rotor, reduce the number of steps in the rotor manufacturing process, and provide a rotor that can reduce the noise and vibration of the motor. And [Structure] A retaining ring 4 is inserted into the shaft 2, and a streak portion 2a is provided at a position where the sensor magnet 5 is inserted, and inner diameters of the retaining ring 4 side end surface and the ball bearing 3 side end surface of the sensor magnet 5 are larger than the diameter of the shaft 2. Then, the gaps 5a and 5b are provided on the end surface side of the shaft 2 and the sensor magnet 5, the sensor magnet 5 is press-fitted into the shaft streak portion 2a, the positioning is performed by the retaining ring 4, and the sensor magnet 5 is fixed by the ball bearing 3 and the retaining ring 4. It has a structure in which it is sandwiched and fixed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of an electric motor used for air conditioners and the like.

[0002]

2. Description of the Related Art In recent years, air conditioners have been strongly required to be comfortable, and it has become necessary to control the number of revolutions of an electric motor, and the number of revolutions of the electric motor is fed back to control the number of revolutions. Came. Therefore, a magnetic sensor is attached to the electric motor to detect the magnetism of a sensor magnet attached to the rotor to generate a rotation speed signal.

A conventional rotor of a motor will be described below. FIG. 3 shows a rotor of a conventional electric motor. 6 is a rotor core, 7 is a ball bearing, 8 is a sensor magnet, 9 is a retaining ring, 10 is a shaft, and 11 is an adhesive. The rotor core 6 is press-fitted or caulked and fixed to the shaft 10. The retaining ring 9 is inserted into the shaft 10, and the ball bearing 7 is press-fitted from the end of the shaft 10 and positioned by the retaining ring 9.
The sensor magnet 8 has an adhesive 11 on the end surface of the rotor core 6.
It is fixed by.

[0004]

However, the configuration of the above-mentioned conventional technique has the following problems.

In the case of FIG. 3, the sensor magnet is fixed to the end surface of the rotor core with an adhesive. Generally, the rotor of an electric motor generates heat and the temperature rises, so a material with high heat resistance is selected for this adhesive, but such an adhesive takes a very long time to cure and raises the temperature to cure it. There are many things. Therefore, the workability is extremely poor, which causes a cost increase. Further, if the temperature is increased during hardening, the ball bearing is inevitably post-press fitted, and the process of producing the rotor is performed twice, which makes automation difficult and causes a cost increase.

The present invention solves the above-mentioned problems of the prior art. It is possible to eliminate the bonding of the sensor magnet, reduce the man-hours of the rotor manufacturing process, and improve the reliability against temperature rise and the cost reduction. The purpose is to provide.

[0007]

In order to achieve this object, the rotor of the present invention has the following structure.

The retaining ring is inserted into the shaft, and the shaft at the position where the sensor magnet is inserted is provided with streaks to increase the inner diameters of the end faces of the retaining ring and the ball bearing of the sensor magnet by the shaft diameter. A clearance is provided on the shaft, the sensor magnet is press-fitted into the streak processing portion of the shaft, the positioning is performed by a retaining ring, and the sensor magnet is sandwiched and fixed by a ball bearing and a retaining ring.

[0009]

With this configuration, the sensor magnet can be securely fixed by the retaining ring and the ball bearing without using an adhesive, and the number of steps in the rotor manufacturing process can be significantly reduced. Further, since the shaft groove for the snap ring can be arranged on the rotor core side as compared with the conventional shaft, the pitch of the groove for the snap ring of the shaft is shortened and the strength of the shaft is increased.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a rotor core, 2 is a shaft, 3 is a ball bearing, 4 is a retaining ring, 5 is a sensor magnet,
Reference numeral 2a is a shaft line stand.

The rotor core 1 is press-fitted or caulked and fixed to the shaft 2, and the retaining ring 4 is inserted in the shaft. The shaft 2 is provided with a streak portion 2a, and the sensor magnet 5 is press-fitted and fixed to the streak portion 2a, and is sandwiched and fixed by the retaining ring 4 and the ball bearing 3.

FIG. 2 shows a sensor magnet fixing portion. 5
Reference numeral a is a clearance portion on the retaining ring 4 side of the sensor magnet, and reference numeral 5b is a clearance portion on the ball bearing 3 side of the sensor magnet.

The sensor magnet 5 is fixed by the streak portion 2a of the shaft 2 and positioned by the retaining ring 4. The shaft magnets 5a and 5b of the shaft 2 and the sensor magnet 5 are arranged such that the sensor magnet 5 is
As a guide for inserting into the groove, and a guide for pressing into the streak portion 2a and cutting scraps when the sensor magnet 5 is cut by the streak portion 2a from the end surface of the sensor magnet 5 to the retaining ring 4 or the ball bearing. It plays a role in fixing cutting scraps so as not to discharge to the 3 side.

The same effect can be obtained even if the streak of the shaft 2 is knurled or a part of the outer diameter of the shaft is increased by working with a punch or the like.

[0016]

As described above, according to the present invention, the sensor magnet can be sandwiched between the retaining ring and the ball bearing and fixed without using an adhesive, and the number of steps of the rotor manufacturing process can be greatly reduced. Further, since the shaft groove for the stop shaft can be arranged closer to the rotor core side than the conventional shaft, the groove pitch for the stop ring of the shaft becomes short, the strength of the shaft is increased, and it is effective in improving the noise and vibration level of the electric motor.

[Brief description of drawings]

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

FIG. 2 is an enlarged cross-sectional view of a sensor magnet fixing portion according to an embodiment of the present invention.

FIG. 3 is a half sectional view of a conventional rotor

[Explanation of symbols]

 2 Shaft 3 Ball bearing 4 Retaining ring 5 Sensor magnet

Claims (4)

[Claims] 1. A rotor having a rotor provided with a position detecting sensor magnet, wherein the sensor magnet is sandwiched and fixed by a retaining ring inserted in a shaft and a ball bearing. 2. The rotor according to claim 1, wherein the shaft and the ball bearing are press-fitted and fixed, and the shaft and the sensor magnet are skimmer springs. 3. The rotor according to claim 1, wherein the shaft is provided with a streak processing portion, and the sensor magnet is press-fitted and fixed to the streak processing portion. 4. The rotor according to claim 1, wherein a clearance is provided in the inner diameter of the sensor magnet between the retaining ring side inserted into the shaft and the ball bearing side end surface of the shaft.