JPH02185697A - Motor-driven blower - Google Patents

Abstract

PURPOSE:To provide a motor driven blower with high vacuum and high efficiency by forming No.1 exhaust passage between a mag. field core and a motor frame, and No.2 exhaust passage between mag. field core and an armature, and by forming No.3 exhaust hole in the motor frame. CONSTITUTION:Air stream generated by a centrifugal fan 1, which is rotated at a high speed by a drive motor 2, is widened gradually by a diffuser 4 of an air guide 13, wherein part will pass No.1 exhaust passage 15 on the outside of a mag. field core 9 upon passing through No.1 return path 5, as shown by arrow A, while another part passes No.2 exhaust passage 17 on the inside of the mag. field core 9 upon passing through No.2 return path 12, as shown by arrow B, to then be exhausted to outside from an exhaust hole 11. Provision of the air guide 13 with No.1 return path 5 and No.2 return path 12 in this manner will divided exhaustion into two routes to lessen the air stream resistance when it passes exhaust passages 15, 17, which should smoothen the exhaustion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electric blower for use in a vacuum cleaner.

2. Description of the Related Art Conventionally, this type of electric blower has had a configuration as shown in FIG. 5, for example.

This will be explained below with reference to FIGS. 5 and 6.

A centrifugal fan 1 is coupled to a shaft 3 of a drive motor 2, an air guide 6 having a plurality of diffusers 4 on the outer periphery and forming a return passage 5 following the diffuser 4, and a casing containing the fan 1 and the air guide 6. 7 is airtightly fixed to the motor frame 8, the fan 1 is rotated at high speed, the discharged air is guided from the diffuser 4 of the air guide 6 to the return passage 5 as shown by the arrow, and the air is passed between the field core 9 and the motor frame 80. The exhaust gas is discharged from an exhaust hole 11 in the opening of the motor frame 9 through an exhaust passage 10 .

Problems to be Solved by the Invention In such a conventional configuration, when the airflow discharged from the fan 1 flows into the diffuser 4, is guided to the return passage 5, and passes through the exhaust passage 10, the field core 9 causes the airflow to flow through the exhaust passage. If the area of 1O is limited and small, there is a problem in that the airflow resistance is large (and the air cannot be discharged smoothly, resulting in a decrease in vacuum pressure and efficiency).

The present invention is intended to solve these problems, and aims to provide an electric blower with high vacuum pressure and high efficiency.

Means for Solving the Problems In order to solve this problem, the present invention includes a centrifugal fan, an air guide that guides the airflow discharged from the fan, and a casing that covers the fan and the air guide. , the airflow guided by the air guide is divided into a first exhaust passage between the outside of the field core and the motor frame, and a second exhaust passage between the inside of the field core and the armature for exhaust. It forms a passage.

With this configuration, when the discharge airflow from the fan passes through the air guide and is discharged from the motor exhaust hole, two exhaust passages are used: the first exhaust passage outside the field core and the second exhaust passage inside the field core.
By passing through several passages, the area of the exhaust passage is expanded, reducing airflow resistance and making the exhaust smoother.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 to 4.

An air guide 1 in which a centrifugal fan 1 is coupled to a shaft 3 of a drive motor 2, has a plurality of diffusers 4 on the outer periphery, and forms a first return passage 5 and a second return passage 12 following the diffuser 4.
3 and a casing 7 having an intake hole 14 in the center are fixed to a motor frame 8, a first exhaust passage 15 is provided between the field core 9 and the motor frame 8, and a first exhaust passage 15 is provided between the field core 9 and the armature 16. A second exhaust passage 17 is formed in the motor frame 8.
An opening for an exhaust hole 11 is provided in the opening.

Next, to explain the operation of this embodiment, the airflow generated by the centrifugal fan l rotated at high speed by the drive motor 2 gradually spreads through the diffuser 4 of the air guide 13, and a portion of the air flows as shown by arrow A. The first return passage 5 passes through the first exhaust passage 15 on the outside of the field core, and a portion passes from the second return passage 12 as shown by arrow B through the second exhaust passage 17 on the inside of the field core. and is discharged to the outside from the exhaust hole 11.

As described above, the present invention divides the exhaust passage into two places by forming the first return passage and the second return passage in the air guide, thereby reducing the resistance of the airflow when passing through the exhaust passage.
This allows for smooth exhaustion.

By improving exhaust efficiency, which exceeds the effects of the invention, high vacuum degree,
In addition to obtaining a highly efficient electric blower, the motor section can be cooled more effectively than before, which is effective in improving the characteristics of the motor, and has great practical effects.

[Brief explanation of the drawing]

FIG. 1 is a half-sectional side view of an electric blower showing an embodiment of the present invention, FIG. 2 is a fan-side plan view of an air guide showing an embodiment of the present invention, and FIG. 0-line cross-sectional side view,
4 is a back view of FIG. 2, FIG. 5 is a half-sectional side view of the conventional example, and FIG. 6 is a back view of the conventional air guide. l...Centrifugal fan, 2...Drive motor, 3...Shaft, 4...Diffuser, 5...Return passage, 7...Casing, 8...Motor frame, 9...Field core, 11...Exhaust hole, 12...Second
return passage, 13... air guide, 14...
...Intake hole, 15...First exhaust passage, 16
... Armature, 17 ... Second exhaust passage. Summary diagram Figure 6, - 1-cho 7 force A F

Claims (1)

[Claims] It has a centrifugal fan connected to a drive motor and a plurality of diffusers on the outer periphery, and a first fan following the diffuser.
an air guide forming a return passage and a second return passage;
The casing has an intake hole in the center and is fixed to the motor frame, and a first exhaust passage is formed between the field core fixed to the motor frame and the motor frame. An electric blower in which a second exhaust passage is formed between a field core and an armature located inside the field core, and an exhaust hole is formed in the motor frame.