JPH0865974A - Rotor for motor - Google Patents

Abstract

PURPOSE: To provide the rotor for a motor in which the quality can be improved by deforming a rotor core by aluminum in flow pressure at the time of die casting the rotor, generating the run-out of a rotor shaft and the bulging of a rotor shaft end, thereby preventing the noise and the vibration. CONSTITUTION: Lightening holes 5 of a flared state are formed at an equal pitch in a circumferential direction over the entire periphery toward a radial direction between the end ring 3 and the core bore 2 of a rotor core 1. Thus, the pressure of a radial direction generated at the time of die casting step is absorbed, and dispersed to prevent the deformation of the rotor end bore.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor rotor.

[0002]

2. Description of the Related Art In recent years, there has been a demand for compactness, low noise, and low vibration, especially for electric appliances and gas equipment-related products. As a result, there is a strong demand for low noise and low vibration of the motor itself. Has been done. Therefore, it is necessary to further improve the accuracy of the motor components, and among them, it is known that the accuracy of the rotor and the rotor shaft of the motor is a major cause of noise and vibration.

A conventional rotor of a motor (hereinafter abbreviated as "rotor") will be described below. 4A is a cross-sectional view of a rotor of a conventional motor, FIG. 4B is a cross-sectional view of the same, and FIG.
(C) is an enlarged cross-sectional view of the same portion. As shown in the drawing, the rotor core 1 having the clamping dowels 4 is formed by crimping the pressed core sheet, and the molten aluminum flows into the rotor slot by the die casting process using aluminum, and the end ring Formed part 3.

However, when aluminum is introduced by the above-mentioned die casting process, a pressure P is generated in the inner diameter direction of the rotor core 1, and this pressure P causes deformation of the inner diameter end surface portion of the rotor. In particular, this deformation was remarkable when the rotor diameter L1 was small and the end ring diameter L2 was small. As a place where this deformation occurs, it is noticeable especially in the inner diameter portion of the rotor inner diameter end surface portion where the clamping dowel 4 where the core sheet is caulked does not exist, and almost no deformation occurs in the area where the clamping dowel 4 exists. The phenomenon that it has not occurred is confirmed. This is because the clamping dowel 4 provided for caulking absorbs the inflow pressure at the time of die casting by the deformation of the dowel itself, and therefore has the effect of suppressing the deformation 7 of the rotor core inner diameter end surface portion. The above-mentioned modification 7 is the rotor shaft 8
This causes press-fitting failure when press-fitting, which is a main cause of the deflection of the rotor shaft 8 and the blistering of the rotor shaft end face portion, resulting in deterioration of the noise and vibration level of the motor.

FIG. 5 (a) is a sectional view of a rotor of another conventional motor, and FIG. 5 (b) is an enlarged sectional view of the same portion. As a recent technological trend, as shown in FIG. By expanding the inner diameters of several sheets, step processing 9 is performed to absorb the deformation caused by the aluminum inflow pressure and prevent deterioration of the quality level.

[0006]

However, in the above-mentioned method, the sticking force between the rotor core 1 and the rotor shaft 8 is reduced, so that in a motor having a thin rotor thickness L3, the pull-out strength of the rotor shaft 8 is small. In the case of a motor with reduced reliability and large vibration, there is a risk that play will occur in the fixed portion between the rotor core 1 and the rotor shaft 8 due to long-term use, and rotation as a motor will become impossible. In addition, in terms of quality control, since the control of the inner diameter of the stepped portion becomes complicated, there is a problem that control loss occurs in the process.

The present invention solves the above problems and prevents the inner diameter of the rotor end face from being deformed, and does not reduce the fixing force between the rotor core and the rotor shaft, thereby reducing the management loss. An object of the present invention is to provide a rotor of a motor that can be used.

[0008]

In order to achieve the above object, the rotor of the motor of the present invention has a pitch between the inner diameter portion of the rotor core and the end ring portion along the circumferential direction, and the outer portion A waste hole is formed in a divergent shape toward the radial direction.

[0009]

According to the above construction, the pressure generated in the inner diameter direction at the time of forming the end ring is absorbed and dispersed by the deformation of the discard hole, and as a result, the deformation of the inner diameter end surface portion of the rotor is prevented.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1A is a plan view of a rotor of a motor according to an embodiment of the present invention, FIG. 1B is a perspective view of the rotor of the motor, and FIG. 2 is a partially enlarged plan view of the rotor of the motor. FIG. 3 is an enlarged plan view of a waste hole provided in the rotor of the motor. As shown in FIG. 1, the core inner diameter portion 2 and the end ring portion 3
And a sacrificial hole 5 is formed between and. As shown in FIG. 2, at least six waste holes 5 are provided at the same radial position along the circumferential direction inside the clamping dowel 4 and at a uniform pitch of 60 ° or less over the entire circumference of the rotor. Form. At this time, in order to maintain the strength (pressure resistance) of the core inner diameter portion 2, it is desirable that the distance between the adjacent disposal holes 5 be at least 2 mm or more at the closest portion. Further, as shown in FIG. 3, the shape of the waste hole 5 is a gradually expanding shape in which Y3 ≧ Y2 ≧ Y1 from the inner diameter direction of the rotor toward the outer diameter direction,
It is desirable to form the width X in the radial direction larger than the maximum width Y3 in the circumferential direction (X> Y3).

In the rotor core 1 having the above-mentioned structure, when the end ring portion 3 is formed by the die casting process, as shown in FIG. However, by absorbing this, the influence of the pressure on the inner diameter end face portion is suppressed and deformation is prevented. Further, by arranging the waste holes 5 uniformly around the entire circumference of the rotor, it is possible to absorb the pressure diverged in the radial direction. Further, by making the size X of the waste hole 5 in the radial direction larger than the circumferential direction Y, it is possible to efficiently absorb the diverged pressure. Further, by forming the uniform pitch discard holes 5, it is possible to prevent the risk that the characteristics will vary due to the rotation of the rotor as a motor, and the quality will be stable. Further, since the step processing is not necessary, it is not necessary to control the quality of the step portion.

[0012]

As described above, according to the present invention, the pressure due to the inflow of aluminum at the time of die casting is absorbed and diverged by the waste hole, so that the deformation of the core inner diameter can be prevented and the rotor shaft is inserted into the rotor core. There is no risk that the rotor shaft will be shaken or blisters at the tip of the motor, and vibration and noise of the motor will be improved. Further, since step processing is not performed, it is possible to reduce management loss, and it is possible to reduce man-hours and improve quality.

[Brief description of drawings]

FIG. 1A is a plan view of a rotor of a motor according to an embodiment of the present invention. FIG. 1B is a perspective view of a rotor of a motor according to an embodiment of the present invention.

FIG. 2 is a partially enlarged plan view of a rotor of a motor according to an embodiment of the present invention.

FIG. 3 is an enlarged plan view of a waste hole provided in the rotor of the motor according to the embodiment of the present invention.

4A is a sectional view of a rotor of a conventional motor, FIG. 4B is a plan sectional view of a rotor of a conventional motor, and FIG. 4C is a partially enlarged sectional view of a rotor of a conventional motor.

FIG. 5A is a sectional view of a rotor of another conventional motor. FIG. 5B is a partially enlarged sectional view of a rotor of another conventional motor.

[Explanation of symbols]

 1 Rotor core 2 Core inner diameter 3 Core end ring 5 Waste hole

Claims (1)

[Claims] 1. A rotor of a motor, characterized in that a pitch is formed along the circumferential direction between the inner diameter portion of the core and the end ring portion, and a waste hole is formed so as to widen toward the outer diameter. .