JP2003314498A - Electric blower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric blower sufficiently cooling a commutator. <P>SOLUTION: This electric blower is provided with: a motor-driven part composed of a rotor 32 and a stator 31 provided around the rotor 32; a fan 39 fixed to one end of an output shaft 33 provided at the rotor 32; the commutator 35 provided at the other end of the output shaft 33 to supply a current to the rotor 32; a fan cover 40 for covering the fan 39; and a cylindrical motor-driven part cover 50 for surrounding the outside of the stator 31. The motor-driven part cover 50 is constituted to guide exhaust air from the fan 39 to the motor- driven part and to exhaust it from an opening at the other end. In this constitution, a guide air passage part 60 is provided for allowing a part of the exhaust air exhausted from the opening, to flow toward the commutator 35. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fan fixed to one end of an output shaft provided on a rotor, a commutator provided to the other end of the output shaft, a fan cover for covering the fan, and an electric section. The present invention relates to an electric blower including a tubular electric part cover surrounding the electric fan.

[0002]

2. Description of the Related Art Conventionally, an electric blower as shown in FIGS. In these figures, 1 is a stator, 2
Is a rotor having a coil 4. Rotor 2 is output shaft 3
A commutator 5 for supplying a current to the coil 4 is fixed to the lower end of the output shaft 3. A brush (not shown) is in contact with the commutator 5. Reference numeral 7 is a brush holder that accommodates a brush.

A centrifugal fan 9 is fixed to the upper end of the output shaft 3. The centrifugal fan 9 is covered with a fan cover 10, and an intake port 8 is provided at the center thereof.

A rectifying plate 11 is provided between the centrifugal fan 9 and an electric part composed of the stator 1 and the rotor 2. The rectifying plate 11 rectifies the wind from the centrifugal fan 9 so that the electric part side. It is supposed to be washed away.

Reference numeral 13 is a frame, and this frame 13
A bearing receiving portion 13B that holds a bearing 14 that rotatably supports the lower end portion of the output shaft 3 is formed therein. Further, the frame 13 is a wall portion 1 surrounding the commutator 5.
Have 3D.

The periphery of the electric section is covered with an electric section cover 15 having a cylindrical cover section 15A, and the electric section cover 20 guides the air from the rectifying plate 11 to the electric section. As a result, the electric part is cooled.

[0007]

However, there is no sufficient gap between the stator 1 and the rotor 2, and as shown in FIG.
Since air is exhausted from 5B in the direction along the output shaft 3, it is not possible to sufficiently secure the air flowing into the frame 13. For this reason, the commutator 5 could not be cooled sufficiently and the temperature rise of the commutator 5 could not be suppressed sufficiently. Further, there is a possibility that a short circuit may occur due to carbon friction powder accumulated inside the frame 13.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an electric blower capable of sufficiently cooling a commutator and blowing away carbon friction powder.

[0009]

In order to achieve the above-mentioned object, the present invention provides a rotor and an electric drive unit which is rotatably provided with respect to the stator, and the rotor. A fan fixed to one end of the output shaft provided, a commutator provided at the other end of the output shaft for supplying a current to the rotor, a fan cover for covering the fan, and a tube surrounding the electric section. An electric blower configured to guide the exhaust air from the fan to the electric portion and to exhaust the air from the opening at the other end of the electric blower. It is characterized in that a guide air passage is provided to allow a part of the wind to flow toward the commutator.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an electric blower 30 according to the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, 31 is a stator, 32 is a rotor having a coil 34, and these constitute an electric section. The stator 31 is composed of a permanent magnet and surrounds the rotor 32. The rotor 32 has an output shaft 33.
The output shaft 33 is fixed to the stator 3 together with the rotor 32.
It is designed to rotate integrally with respect to 1.

A centrifugal fan 39 is fixed to one end of the output shaft 33, and the centrifugal fan 39 rotates together with the rotor 32. The centrifugal fan 39 is covered with a fan cover 40, and an intake port 41 is provided in the center thereof. The rotation of the centrifugal fan 39 sucks air from the intake port 41 and causes it to flow in the direction of the arrow indicated by the solid line.

A commutator 35 is fixed to the other end of the output shaft 33. A pair of brushes (not shown) are in contact with the commutator 35. Each brush is provided in each of a pair of brush holders 37 attached to the frame 43 holding the stator 31. The pair of brush holders 37 face each other, and a spring (not shown) is attached between the end of each brush holder 37 and the brush. The brush is elastically contacted with the commutator 35 by this spring.

A rectifying plate 54 is provided between the electric section and the centrifugal fan 39. The rectifying plate 54 is used for the centrifugal fan 3.
The air from 9 is rectified and sent to the electric part side.

The frame 43 is formed with a bearing receiving portion 44 holding a bearing 55 rotatably supporting the lower end portion of the output shaft 33. Further, the frame 43 has a peripheral wall portion 43A surrounding the commutator 35.
3A is formed with a pair of openings 43B, 43C facing each other in a direction orthogonal to a straight line connecting the pair of brush holders 37.

The periphery of the electric section is surrounded by a cylindrical electric section cover 50 having both ends opened.
Is configured to guide the air rectified by the rectifying plate 54 at one end side to the electric section, whereby the electric section is cooled. This electric section cover 5
0 is fixed to the flow straightening plate 54 by screws B.

In FIG. 2C, the electric part cover 50 is formed flat in the vertical direction, the wall parts 51 on the left and right are located at the same position as the outer peripheral edge of the current plate 54, and the brush holder 37. Is located above the outer end of the and is formed in an arc shape. The upper and lower wall portions 52 are located inside the outer peripheral edge of the straightening vane 54, and the distance between the wall portions 52 and 52 is set smaller than the distance between the wall portions 51 and 51. The cross-sectional area of the exhaust air passage surrounded by the walls 51 and 52 is made as small as possible so that a predetermined flow velocity can be obtained.

The brush holder 37 is located below the cross-sectional area. That is, the brush holder 37 is arranged in the exhaust air passage projected cross-sectional area of the electric section cover 50.

As described above, since the brush holder 37 is arranged within the exhaust air passage projected cross-sectional area of the electric portion cover 50, the air exhausted from the electric portion cover 50 hits the entire brush holder 37 and holds the brush. The entire container 37 can be cooled reliably. Therefore, the brushes 36A, 36B
It is possible to prevent the temperature rise of the electric blower, and to prevent the output and efficiency of the electric blower from decreasing.

At the other end, which is the lower end of the electric portion cover 50, a guide air passage portion 60 is integrally formed at a position facing the opening 43B of the frame 43, and the guide air passage portion 60 is formed.
As shown in FIGS. 1 and 2B, is a guide wall portion 61 that extends downward and has a tip portion 61a bent inward,
The guide wall portion 61 has side wall portions 62, 62 respectively provided on both sides of the guide wall portion 61 so as to face each other. Side wall portion 62, 62
Is formed inside the electric section cover 50, and the side wall section 6
The upper part of 2,62 (in FIG. 2 (B)) is expanded. A guide air passage is formed by the guide wall portion 61 and the side wall portion 62.

A recess 55 is formed in the lower portion (in FIG. 2B) of the electric section cover 50 facing the opening 43C of the frame 43. The upper end of the recess 55 has the opening of the frame 43. A lid wall portion 56 extending to the upper edge of 43C is formed, and side wall portions 57, 57 extending to the side edges of the opening 43C of the frame 43 are formed at both ends of the recess 55. The side walls 57, 57 surround the upper portion of the opening 43C of the frame 43 and the upper portions of both side portions.

Next, the operation of the electric blower configured as described above will be described.

When the fan 39 is rotated by the rotation of the rotor 32 and the output shaft 33, air is sucked from the intake port 41 of the fan cover 40, and the sucked air is introduced from the direction indicated by the solid line into the electric section cover 50. It flows. The air flowing into the electric power unit cover 50 cools the electric power unit and is exhausted to the outside from the opening 50A of the electric power unit cover 50.

Further, part of the air flowing downward (in FIG. 1) along the inner peripheral surface of the electric power unit cover 50 enters between the side wall portions 62, 62 of the guide air passage portion 60, and the side wall portion 62. The air that has entered between the space 62 and the space 62 is guided by the guide wall portion 61 and the side wall portions 62 and 62, and the frame 43
It sprays toward the commutator 35 through the opening 43B. Therefore, the exhaust air entering the frame 43 can be sufficiently secured, and the commutator 35 is sufficiently cooled. Therefore, the temperature rise of the commutator 35 can be sufficiently suppressed, and the input of the electric blower 30 can be improved.

Further, since it is possible to sufficiently secure the exhaust air flowing into the frame 43, it is possible to prevent the abrasion powder of the brush from being accumulated in the frame 43.
It is possible to prevent a short circuit, a poor pressure resistance, and a reduction in the life of the motor due to the adhesion of abrasion powder.

The air blown onto the commutator 35 is supplied from the opening 43C of the frame 43 to the concave portion 55 of the electric section cover 50.
Exhaust is exhausted to the outside through the lower side. Since the lid wall portion 56 and the side wall portions 57, 57 are formed in the recess 55, the air flowing downward along the inner peripheral surface of the electric portion cover 50 should hit the lid wall portion 56. Therefore, the flow of air exhausted from the opening 43C of the frame 43 is not obstructed. Therefore, the air exhausted from the opening 43C of the frame 43 flows smoothly, and the exhaust air flowing in the frame 43 can be more sufficiently secured.

Further, the side walls 57, 57 of the recess 55 prevent the air flowing along the inner peripheral surface of the electric power unit cover 50 from entering from the side and entering the recess 55. The air flowing from the side does not obstruct the flow of air exhausted from the opening 43C of the frame 43. Therefore, it is possible to further secure the exhaust airflow flowing in the frame 43.

FIG. 3 shows another electric section cover 70. The cylindrical cover portion 71 of the electric portion cover 70
The guide air duct portion 60 is formed in the.

[0029]

As described above, according to the present invention, the commutator can be sufficiently cooled and the friction powder of the brush can be blown off.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a structure of an electric blower according to the present invention.

FIG. 2 is a perspective view for explaining the structure of the electric blower shown in FIG. 1, and FIG. 2A is a perspective view showing an electric drive unit and a fan case. (B) is a perspective view showing an electric power unit cover. (C) is a bottom view.

FIG. 3 is a perspective view showing another example of an electric power unit cover.

FIG. 4 is a cross-sectional view showing a structure of a conventional electric blower.

5 is an exploded perspective view for explaining the structure of the electric blower shown in FIG.

[Explanation of symbols]

31 Stator 32 rotor 33 Output shaft 35 commutator 39 fans 40 fan cover 50 Electric section cover 60 Guide air passage

Claims (2)

[Claims] 1. An electric drive unit comprising a stator and a rotor rotatably provided with respect to the stator, a fan fixed to one end of an output shaft provided on the rotor, and an output thereof. A commutator provided at the other end of the shaft for supplying an electric current to the rotor, a fan cover for covering the fan, and a tubular electric part cover surrounding the electric part are provided. In an electric blower configured to guide exhaust air from a fan to the electric section and to exhaust the air from the opening at the other end, a guide air passage for flowing a part of exhaust air exhausted from the opening toward the commutator. An electric blower characterized by being provided with. 2. A frame having a peripheral wall portion that rotatably holds the other end of the output shaft and surrounds the commutator, wherein the peripheral wall portion has openings facing each other with the output shaft interposed therebetween. The guide air passage allows exhaust air to flow from one opening of the peripheral wall toward the other opening, and does not change the flow of exhaust air discharged from the other opening of the peripheral wall. The electric blower according to claim 1, wherein a lid wall portion is provided in an opening at the other end of the electric portion cover.