JPS6140495A - Electric blower - Google Patents

Abstract

PURPOSE:To improve blast efficiency ever so better, by install a step differential in a partition wall plate of an air guide, while placing a start end of a diffuser wall on a plene surface part in a bottom surface of a diffuser, in case of a centrifugal blower. CONSTITUTION:A shoulder part 27 of a casing 19 is formed in large radius form, while a partition wall 28, separating the side where a diffuser exists and the side where a return passage 18 exists in an air guide 21, has a step differential between a lower part of an impeller 12 and the outer circumferential part at the side of the diffuser 17. In addition, a start end of a diffuser wall 22 is situated on a plane surface 29. Therefore, an airstream discharged out of the impeller is in no case expanded so suddenly, and since it is led into the diffuser wall as being rectified at the plane surface part of the diffuser, a flow of air becomes smooth enough, thus improvements in blast efficiency is well promotable.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electric blower for generating vacuum pressure used in vacuum cleaners and the like used in general households.

Conventional Structure and Problems Conventionally, this type of electric blower has an impeller 1, a diffuser 2 surrounding it, and a return 9.
It consists of an air guide 4 in which a passage 3 is integrally formed, and a casing 6 that covers the impeller 1 and air guide 4, presses the upper end of the diffuser 2, and is attached to the motor bracket upper plate 5 by press fitting. ing. or,
The air guide 4 is formed by connecting the diffuser 2, the passage 7 surrounded by the casing 6, and the return passage 3. It was flowing from inside of 8 to Morph's exhaust port 9.

As shown in FIG. 2, the diffuser wall 10 is provided upright on a partition plate 11 that vertically divides the diffuser 2 and the return jm path 3.

That is, the height of the diffuser wall 10 is considerably higher than the width of the impeller 1 in the vertical direction.

Therefore, near the outer periphery of the impeller 1, the air discharged from the innovator 1 is rapidly expanded in the vertical direction before entering the diffuser 2, resulting in increased flow loss and a decrease in air blowing efficiency. It had become.

OBJECTS OF THE INVENTION The present invention solves the conventional drawbacks as described above and provides an electric blower with high air blowing efficiency.

Structure of the Invention The electric blower of the present invention includes an impeller, an air guide, and a casing that covers these, and the air guide has a diffuser and a return passage formed integrally with a partition plate in between, and the air guide has a diffuser and a return passage interposed therebetween, and The plate has a surface facing the bottom of the impeller,
A step is provided between the diffuser, which is the outer circumference of the impeller, so that the diffuser becomes higher, and the bottom of the diffuser has a flat plane in the radial direction of the impeller at the part close to the impeller, and then This configuration forms an inclined surface, and the starting end of the diffuser wall is located on the plane.This diffuser configuration allows the air to flow within the diffuser very smoothly, improving air blowing efficiency. It is something that can be planned.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In FIGS. 3 to 6, reference numeral 12 denotes an impeller, which is attached to the motor shaft 13 through a washer 14 and a spacer 16 by tightening with a nut 16. A diffuser 17 that is located around the impeller 12 and guides air from the impeller 12, a return passage 18, and a casing 1 that communicates the diffuser 17 and the return passage 18.
The air guide 21 is formed integrally with the communication passage 20 surrounded by the casing 19. ing. 24 is the motor bracket body, in which the rotor 25 and stator 26 are installed.
is located.

The shoulder portion 27 of the casing 19 is formed into a largely rounded shape, and the partition wall 28 that separates the air guide 21 from the side where the diffuser 17 is located and the side where the return passage 18 is located is located at the lower part of the impeller 12 on the diffuser 17 side. There is a step between the outer circumferential portion of the impeller 12 and the outer circumferential portion of the impeller 12 where the diffuser wall 22 is present, and the outer circumferential portion of the impeller 12 where the diffuser wall 22 is located is higher than the seventh bracket upper plate 23 when viewed in the direction of the motor shaft 13. ing. As shown in FIG. 4, the bottom surface of the diffuser 1.7, which is the raised part of the step, has a flat plane 29 in the radial direction of the impeller 12 in the part near the outer periphery of the impeller 12. Subsequently, an inclined surface 30 is provided which is inclined toward the outer circumference of the air guide 21 so as to approach the motor bracket upper plate 23 when viewed in the direction of the motor shaft 13. Further, the starting end 31 of the diffuser wall 22 is located on the plane 29 as shown in FIG.

To explain the operation in the above configuration, the impeller 12 rotates together with the motor shaft 13 as the motor operates.

Therefore, air is sucked into the impeller 12, then discharged to the diffuser 17, flows in the order of communication passage 2Q→return passage 18→monochrome bracket body 24, and is discharged to the outside.

To explain in more detail the flow of air after it is discharged from the impeller 12, due to the effect of the step provided in the partition wall 28, the diffuser 1 is free from sudden expansion in the vertical direction as in the conventional case.
The air flowing into the diffuser 17 first changes its flow path in the direction of the motor shaft 13 at the portion 29 where the bottom surface of the diffuser 17 is flat, and is smoothly rectified until it reaches the starting end of the diffuser wall provided on the flat surface 29. 31, the air guide 21 is directed toward the outer circumferential direction of the diffuser wall 22, and then the inclined surface 30 and the casing 1
Guided by the rounded shape of the shoulder 27 of 9, the flow path is smoothly changed toward the motor shaft 13.

In this way, immediately after the air flows into the diffuser 17, it is rectified on the plane 29 and directed toward the outer circumference of the air guide 21, so that the flow becomes very smooth. This has the effect of improving air blowing efficiency.

In this embodiment, the starting end 3 of the diffuser wall 22
1 is made to coincide with the innermost side of the plane 29, but the starting end 32
should be within the plane 29, and a configuration as shown in FIG. 6 is also conceivable. The point is that the effect can be obtained if the air is guided to the diffuser wall 22 during rectification on the plane 29.

Effects of the Invention As is clear from the above-mentioned embodiments, in the electric blower of the present invention, the impeller is effectively The airflow discharged from the diffuser does not expand rapidly and is rectified on the flat surface of the diffuser before being guided to the diffuser wall, making the air flow smoother and improving the air blowing efficiency. .

[Brief explanation of drawings]

Figure 1 is a cutaway perspective view of the main parts of a conventional electric blower;
3 is a sectional view of the main part of an embodiment of the electric blower according to the present invention. FIG. 4 is a sectional view of the air guide. FIG. 5 is a sectional view of the air guide. FIG. 6 is a partially enlarged plan view of the air guide in another embodiment. 12... Impeller, 13... Motor shaft, 17... Diffuser, 18... Return passage, 19... Casing, 21... ...
・Air guide, 22...Diffuser wall, 28・
...Partition plate, 29...Flat surface, 39...
... Inclined surface, 31 ... Diffuser wall starting end. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure M2 Figure 3

Claims (2)

[Claims] (1) The impeller attached to the motor shaft, the air guide that guides the air from the impeller, and the impeller and
The air guide is composed of a casing that covers the air guide, and the air guide is integrally formed with a diffuser and a return passage across a partition plate, and the impeller side of the partition plate has a surface facing the lower part of the impeller, and a diffuser that is the outer periphery of the impeller. A step is provided between the diffuser so that the diffuser becomes higher, and the bottom surface of the diffuser has a flat plane in the radial direction of the impeller at a portion close to the impeller, and then an inclined surface is formed, and the diffuser is formed on the plane. Electric blower located at the beginning of the wall. (2) The electric blower according to claim 1, wherein the starting end of the diffuser wall and the innermost circumferential end of the plane on the bottom surface of the diffuser are aligned in the radial direction of the impeller.