JPH1037898A - Motor-driven blower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the performance of a motor-driver blower equipped with a diffuser by making the elevation of a wall surface on each inner circumferential side of plural pieces of circular arc blades higher than that of a wall surface on the outer circumferential side, and preventing any turbulent flow from occurring. SOLUTION: This motor-driven blower 12 installed in a vacuum cleaner is equipped with a centrifugal fan 16 being rotated by drive of a motor 14, and a diffuser 18 locked to a casing 13, respectively. It is also provided with plural pieces of circular blades 18d erected in place nearer to a peripheral edge part of the diffuser 18 so as to be situated in an outer circumferential part of the centrifugal fan 16. In order to make the elevation of a wall surface at the inner circumferential side of these circular blades 18d higher than that of a wall surface at the outer circumferential side, a lot of grooves 18e are formed along the base of each inner circumferential side of the circular blades 18d. In this constitution, a current flowing among these circular blades 18d is hard to converge on the wall surface to be situated at the inner circumferential surface side of a diffuser 18. Thus, a suction effect is elevated high, and thus performance in the blower is sharply improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric blower provided in a vacuum cleaner for generating suction air for sucking dust into the vacuum cleaner.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG.
Is provided with an electric blower 2 that generates suction air for sucking dust into the electric vacuum cleaner 1.

[0003] As shown in FIG.
A hollow casing 3 composed of two cylindrical bodies, large and small; a motor 4 provided in the casing 3; a centrifugal fan 6 fixed to a rotating shaft 5 of the motor 4 and rotated by driving the motor 4; And a diffuser 8 fixed via a bracket 7.

As shown in FIGS. 5A and 5B, the diffuser 8 includes a disc-shaped base 8a, a through hole 8b formed at the center of the base 8a, through which the rotary shaft 5 passes, and a bracket 7. Screw holes 8c, 8c for fixing with screws 9
And a plurality of arc-shaped blades 8d, 8d, ... standing upright near the outer peripheral edge of the diffuser 8 so as to be located on the outer peripheral portion of the centrifugal fan 6.

When the rotating shaft 5 rotates, the centrifugal fan 6 rotates integrally with the rotation, and the rotation causes the suction air to pass through the centrifugal fan 6 from the suction opening 3a formed on the suction side of the casing 3 (see FIG. 1). 6), and is guided to the motor 4 after passing between the arcuate blades 8d, 8d,... From the outer peripheral side to the inner peripheral side of the diffuser 8.

At this time, the performance of the electric blower 2 is represented by a power determined by the degree of vacuum and the amount of suction air in the dust collecting chamber 10 in front of the electric blower 2. Since the reverse wind efficiency of the electric blower 2 is determined by the power / axial output by the centrifugal fan 6 and the diffuser 8, the shape and the like of the diffuser 8 are important points in performance.

[0007]

By the way, in the electric blower 2 constructed as described above, when the flow of the wind on the diffuser 8 is visualized, the arc-shaped blades 8d, 8
There is a problem that the wind flows intensively on the inner wall surface located on the inner peripheral surface side of the diffuser 8 between d... and turbulence occurs.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electric blower capable of preventing occurrence of turbulence and improving performance.

[0009]

According to one aspect of the present invention, there is provided a diffuser having a plurality of arc-shaped blades provided on an outer peripheral portion of a centrifugal fan rotated by driving a motor. In the electric blower provided with, the gist of the invention is that the height of the inner peripheral wall of the plurality of arc-shaped blades is higher than the height of the outer peripheral wall.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the electric blower of the present invention will be described with reference to the drawings.

In FIG. 2, an electric blower 12 provided in a conventional vacuum cleaner includes a hollow casing 13 composed of two large and small cylindrical bodies, a motor 14 provided in the casing 13, and a motor 14. Centrifugal fan 16 fixed to rotating shaft 15 and rotated by driving of motor 14
And a diffuser 18 fixed to the casing 13 via a bracket 17.

As shown in FIG. 1A, the diffuser 18 is fixed to a disc-shaped base 18a, a through-hole 18b formed at the center of the base 18a and through which the rotating shaft 15 passes, and a screw 19 to the bracket 17. Screw holes 18
c, 18c, a plurality of arc-shaped blades 18d, 18d,... erected near an outer peripheral edge of the diffuser 18 so as to be located on an outer peripheral portion of the centrifugal fan 16, and a plurality of arc-shaped blades 18d, 18d. In order to make the height of the circumferential (center) wall surface higher than the height of the outer circumferential wall surface, FIG.
As shown in (B) to (D), the arc-shaped blades 18d,
Grooves 18e, 18 formed along the inner peripheral base of 18d
e ... are provided.

In the above configuration, when the rotating shaft 15 rotates, the centrifugal fan 16 rotates together with the rotation, and the rotation causes the suction air to flow from the suction opening 13a formed on the suction side of the casing 13 to the centrifugal fan. 16 (FIG. 1
(Refer to arrow (A)) and further pass through the arc-shaped blade 1
8d, 18d... Are passed from the outer peripheral side to the inner peripheral side of the diffuser 18 and then guided to the motor 14.

At this time, the arc-shaped blades 18d, 18d...
It is difficult for the wind flowing between to concentrate on the wall surface located on the inner peripheral surface side of the diffuser 18, so that the problem that turbulence occurs is eliminated, the suction effect can be improved, and the performance as the electric blower 12 can be improved. It can be greatly improved.

If the overall height of the arc-shaped blades 18d, 18d,... Is simply increased, the air volume is increased, but the degree of vacuum at the air volume of the maximum efficiency character (the dust collection chamber) is reduced, and the suction efficiency is reduced. However, according to the present invention, the groove 18
By raising only the inner wall surface by e, 18e, etc., such a problem can be solved.

In the above embodiment, the groove 18e
Are simply formed on the inner peripheral wall base of the arc-shaped blade 18d. For example, as shown in FIGS. 3A to 3D, the grooves 28e are formed on the outer peripheral side of the diffuser 28. Or deeper, or from Fig. 4 (A)
As shown in (D), the grooves 38e are not particularly limited, for example, the grooves 38e are deeper and wider in width toward the outer peripheral side of the diffuser 28.

At this time, the arc-shaped blades 18d, 28d,
The grooves 18e, 28e, 38e are formed in the arc-shaped blade 1 such that the height of 38d is higher from the middle to the outer peripheral edge side.
The same effect can be obtained by forming only from the middle part of 8d, 28d, 38d toward the outer peripheral edge side.

FIGS. 3A to 3D and FIG. 4A
In (D), 28a and 38a are disc-shaped bases, 28b and 38b are through holes formed at the centers of the bases 28a and 38a and through which the rotating shaft 15 passes, and 28c and 38c.
Is a screw hole for fixing the bracket 17 with the screw 19,
Reference numerals 28 d and 38 d denote a plurality of arc-shaped blades which are provided upright on the outer peripheral edge of the diffusers 28 and 38 so as to be located on the outer peripheral portion of the centrifugal fan 16.

[0019]

As described above, in the electric blower of the present invention, the height of the inner peripheral wall of the plurality of arc-shaped blades is made higher than the height of the outer peripheral wall.
Turbulence can be prevented from occurring, and performance can be improved.

[Brief description of the drawings]

FIG. 1 shows an electric blower according to an embodiment of the present invention, wherein (A) is a front view of a diffuser, and (B) is FIG.
FIG. 1A is an enlarged sectional view taken along line AA, and FIG.
FIG. 1A is an enlarged sectional view taken along line BB, and FIG.
It is an expanded sectional view which follows a CC line of (A).

FIG. 2 is a half sectional view of the electric blower.

3 (A) is a front view of a diffuser, FIG. 3 (B) is an enlarged sectional view taken along line DD of FIG. 3 (A), and FIG. FIG. 3A is an enlarged sectional view taken along line EE, and FIG. 3D is an enlarged sectional view taken along line FF in FIG.

4A and 4B show a modified example of the electric blower of the present invention, wherein FIG. 4A is a front view of a diffuser, FIG. 4B is an enlarged sectional view taken along line GG of FIG. 4A, and FIG. 4A is an enlarged sectional view taken along line HH, and FIG. 4D is an enlarged sectional view taken along line II in FIG.

5A and 5B show a conventional electric blower, wherein FIG. 5A is a front view of a diffuser, and FIG. 5B is a sectional view of the diffuser.

FIG. 6 is a half sectional view of the electric blower.

FIG. 7 is a side view of the vacuum cleaner with a part thereof broken away.

[Explanation of symbols]

 12 ... Electric blower 14 ... Motor 16 ... Centrifugal fan 18 ... Diffuser 18d ... Arc blade

Claims (3)

[Claims] An electric blower provided with a diffuser having a plurality of arc-shaped blades standing on an outer peripheral portion of a centrifugal fan rotated by driving of a motor, wherein an inner peripheral wall surface of the plurality of arc-shaped blades is provided. An electric blower characterized in that the height is higher than the height of the outer peripheral wall. 2. The electric blower according to claim 1, wherein the inner peripheral wall surface of the plurality of arc-shaped blades becomes higher toward the outer peripheral side of the diffuser. 3. The electric blower according to claim 1, wherein the inner peripheral wall surface of the plurality of arc-shaped blades is made higher from the middle to the outer peripheral side.