JPH06257598A - Motor-driven fan - Google Patents

Abstract

PURPOSE:To provide a low-vibration motor-driven fan by decreasing the turbulent flow of air which is generated when the flow of air expelled from a fan is allowed to pass through an air guide and then to flow into a bracket, thereby improving the efficiency of a motor, and by increasing the strength of the bracket. CONSTITUTION:A plurality of recessed ventilation flues 7c are radially provided at a curvature-chamfered portion extending to the cylindrical portion 7a of a bracket 7 from a planar portion 7b projecting outside of the cylindrical portion 7a, and turbulent flow generated at the time of refraction is reduced by the plurality of recessed ventilation flues provided radially at the curvature- chamfered portion extending to the cylindrical portion of the bracket 7 from the planar portion projecting outside of the cylindrical portion, and then vibration can be reduced through improvement of motor efficiency and through increase in the strength of the bracket 7, achieved by a rib effect.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric blower used in household vacuum cleaners and the like.

[0002]

2. Description of the Related Art With the recent demand for miniaturization of home electric appliances, there is an increasing demand for miniaturization of electric motors. In addition, competition for higher output in vacuum cleaners is intensifying, and there is a demand for a high-output and high-efficiency electric blower, which is a basic component.

A conventional electric blower will be described below with reference to the drawings. 4 and 5 are a half sectional view showing the structure of a conventional electric blower and an enlarged view showing the details of the structure.
In FIG. 4, 1 is a stator having a stator core 1a, 2 is a rotor, and 3 is a cylindrical portion 3a for accommodating the rotor 2 arranged inside the stator 1 at one opening edge of this cylinder. Part 3
It is a bracket formed by providing a flat surface portion 3b protruding to the outside of a.

Further, 4 is a rotary fan fixed to the rotor shaft 2a of the rotor 2, 5 has a plurality of air inlets in the peripheral portion, and a plurality of rectifying air passages 5a connected to these air inlets are provided on the inner surface. Is formed to cover the rotary fan 4 and one end opening of the bracket 3, and guides the air discharged from the rotary fan 4 into the bracket 3, and 6 is a fan case that covers the air guide 5 and the rotary fan 4. Then, it is press-fitted and fixed to the bracket 3.

The operation of the electric blower configured as described above will be described below. When power is applied to the electric blower, the rotor 2 rotates at high speed. Next, as the rotor 2 rotates, the rotary fan 4 fixed to the rotor shaft 2a rotates. Therefore, when the rotary fan 4 rotates at high speed, air is sucked from the suction port 6a of the fan case 6, passes through the inside of the rotary fan 4, and the air guide 5
Is guided to the inside of the bracket 3. After that, the air introduced into the bracket 3 is discharged to the outside while cooling the stator 1 and the rotor 2.

[0006]

However, in the above-mentioned conventional structure, in order to mount the air guide 5 and the bracket 3, it is necessary to provide the bracket 3 with the flat surface portion 3b projecting to the outside of the cylindrical portion 3a. Therefore, when the outer diameter of the bracket 3 is reduced, the area of the flat surface portion 3b is reduced, and the R chamfered portion must be reduced from the flat surface portion 3b to the cylindrical portion 3a.

Therefore, when the air discharged from the rotary fan 4 as shown in FIG. 5 flows through the inside of the air guide 5 into the inside of the bracket 3, it extends from the flat surface 3b to the outside of the bracket 3 to the cylindrical portion 3a. Since the R chamfered portion to abruptly changes the flow of air, air turbulence occurs and air blowing performance is deteriorated. Further, the R chamfering from the flat surface portion 3b protruding to the outside of the bracket 3 to the cylindrical portion 3a is inevitably small, so that there is also a problem that the strength is insufficient.

In view of the above drawbacks, an object of the present invention is to provide an electric blower capable of improving the blowing performance with a simple structure.

[0009]

To achieve this object, the electric blower of the present invention has a plurality of radial chamfered portions extending from the flat surface of the bracket to the outside of the cylindrical portion toward the cylindrical portion. The configuration is such that a concave ventilation passage is provided.

[0010]

With this structure, it is possible to prevent a sudden change in the flow of air when the air discharged from the rotary fan passes through the inside of the air guide and flows into the inside of the bracket, and it is possible to improve the blowing performance. .

[0011]

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

FIG. 1 is a half sectional view showing the construction of the electric blower of the present invention, FIG. 2 is an enlarged view showing the details of the construction, and FIG. 3 is a plan view seen from the bracket side. Figure 1,
In FIGS. 2 and 3, 1 is a stator and 2 is a rotor. Four
Is a rotary fan, 5 is an air guide, and 6 is a fan case, which are the same as in the conventional example. Reference numeral 7 has a flat surface portion 7b protruding outward from a cylindrical portion 7a that houses the rotor 2 arranged inside the stator 1, and the flat surface portion 7b to the cylindrical portion 7a.
It is a bracket in which a plurality of recessed ventilation passages 7c are radially provided on the R chamfered portion facing toward.

With the above structure, the operation will be described below. When power is applied to the electric blower, the rotor 2 rotates at high speed. Next, as the rotor 2 rotates, the rotary fan 4 fixed to the rotor shaft 2a rotates. Therefore, when the rotary fan 4 rotates at high speed, air is sucked from the suction port 6a of the fan case 6 and guided through the inside of the rotary fan 4 into the bracket 7 by the air guide 5. Here, when the air discharged from the air guide flows into the cylindrical portion 7a from the flat surface portion 7b, the air passage 7
Since it is rectified by c, a smooth air flow can be obtained, and the blowing performance can be improved. Further, by providing the ventilation passages 7c radially in the R chamfered portion from the flat surface portion 7b to the cylindrical portion 7a, the strength of the bracket 7 can be increased by the rib effect.

[0014]

As described above, according to the present invention, a plurality of recessed ventilation passages are provided radially in the R chamfered portion extending from the flat surface portion of the bracket to the outside of the cylindrical portion toward the cylindrical portion. It is possible to realize an excellent electric blower that can reduce air turbulence in the R chamfered portion to improve the blowing performance and also increase the bracket strength due to the rib effect.

[Brief description of drawings]

FIG. 1 is a half sectional view showing a configuration of an electric blower according to an embodiment of the present invention.

FIG. 2 is an enlarged view showing details of the configuration of the electric blower according to the embodiment of the present invention.

FIG. 3 is a plan view showing the configuration of an electric blower according to an embodiment of the present invention.

FIG. 4 is a half sectional view showing a configuration of a conventional electric blower.

FIG. 5 is an enlarged view showing details of the configuration of a conventional electric blower.

[Explanation of symbols]

 1 Stator 2 Rotor 4 Rotating fan 5 Air guide 6 Fan case 7 Bracket 7c Ventilation path

Claims (1)

[Claims] 1. A stator having a stator iron core, a rotor arranged inside the stator, and a flat surface projecting to the outside of the cylindrical portion at one opening edge of the cylindrical portion for accommodating the rotor. Brackets formed by providing parts, a rotary fan fixed to the shaft of the rotor, a plurality of air inlets in the peripheral portion, and a plurality of rectifying air passages connected to these air inlets are provided on the inner surface. An air guide that is provided to cover one end opening of the rotary fan and the bracket and guides the air discharged from the rotary fan into the bracket; and one end opening side of the bracket that covers the air guide and the rotary fan. An electric blower having a fan case attached to the bracket, and a plurality of recessed portions radially formed in the R chamfered portion extending from the flat surface portion of the bracket that extends outward from the cylindrical portion toward the cylindrical portion. An electric blower, characterized in that a ventilation passage.