JPH07332294A - Electric blower - Google Patents

Abstract

PURPOSE:To ensure tightness between an air guide inner hole part and a bearing housing so as to prevent the lowering of blasting performance by forming a thin-walled dip part, protruding toward the center, at the nearly center part of the air guide, and bringing this dip part into close contact with the bottom part of the outer peripheral groove of the bearing housing. CONSTITUTION:In an air guide 5 formed of synthetic resin, a thinwalled dip part 5a protruded while being gradually inclined toward the center part along the inclined part of the outer peripheral groove 4b of a bearing housing is formed at the nearly center part. The thinwalled dip part 5 is fixed to a bracket 4 by a fitting screw 6 in the state of being in close pressure contact with the bottom part of the outer peripheral groove 4b of the bearing housing 4a. Since tightness to the groove 4b is secured by the dip part 5a of the air guide 5, high pressure air led into the air guide 5 is smoothly guided into a bracket B3 without the leak of air in the bracket B3 onto the fan 7 side.

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 for an electric vacuum cleaner or the like.

[0002]

2. Description of the Related Art Conventionally, in this type of electric blower, a fan is rotated at a high speed, high-speed air discharged from the fan is guided into a bracket by an air guide, and is discharged while cooling the electric motor. However, since the bearing housing of the bracket was inserted into the inner hole formed in the center of the air guide, a gap was created between the inner hole and the bearing housing, and air on the electric motor side could flow from this gap. Leakage to the fan side causes a decrease in air pressure and a deterioration in characteristics.

In order to solve this problem, a structure in which a convex portion is formed on the inner hole surface of the air guide so as to be in close contact with the outer peripheral portion of the bearing housing is disclosed in Japanese Utility Model Laid-Open No. Sho 60-194191.
And Japanese Patent Publication No. 4-183996.

[0004]

However, in the conventional structure, there is a problem that the inner diameter of the convex portion of the inner hole and the outer diameter of the bearing housing are varied due to the molding conditions of the air guide, and a gap is generated. On the contrary, in order to ensure tightness, in the structure where a thin portion is formed on the inner hole surface and is fitted and closely fitted to the outer peripheral portion of the bearing housing to secure tightness, the air guide is There was a problem in assembling due to the fitting size when it was inserted into.

The present invention eliminates the above problems,
(EN) Provided is an electric blower capable of ensuring tightness between an inner hole of an air guide and a bearing housing by a comparatively easy method to prevent deterioration of air blowing performance, and improving assemblability of an air guide. This is the purpose.

[0006]

In order to solve the above-mentioned problems, the electric blower of the present invention is arranged such that the air guide is gradually inclined toward the center of the air guide along the inclined portion of the groove on the outer periphery of the bearing housing. While forming a protruding thin-walled dip portion, the dip portion is brought into contact with the bottom portion of the groove on the outer periphery of the bearing housing of the bracket A, and when the air guide is tightened and fixed to the bracket A with a mounting screw, the thin-walled dip portion is formed. It is characterized in that the dip portion of (3) is brought into pressure contact with the bottom portion of the groove on the outer periphery of the bearing housing.

[0007]

As described above, according to the present invention, the thin-walled dip portion is brought into pressure contact with the bottom portion of the groove on the outer periphery of the bearing housing so that tightness can be surely secured and an air guide can be easily inserted. A structure that can be improved and, in turn, can be automatically assembled.

[0008]

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

FIG. 1 is an external view of a partial cross section showing the structure of an electric blower according to an embodiment of the present invention, FIG. 2 is an enlarged view of a main part of the partial cross section of the embodiment of the present invention, and FIG. FIG. 7 is a partially enlarged view of the air guide in the embodiment of FIG.

In FIGS. 1, 2 and 3, 1 is a stator, 2
Is a rotor, and 3 is a bracket B, which is formed by providing a flat surface portion 3b projecting to the outside of the cylindrical portion 3a at one opening edge of the cylindrical portion 3a for holding the rotor 2 arranged inside the stator 1. There is. Reference numeral 4 denotes a bracket A, which is a bearing 2 of the rotor 2.
The bearing housing 4a for holding and supporting a and a circumferential groove 4b on the outer circumference of the bearing housing 4a are fixed to the flat surface portion 3b of the bracket B3 by covering one end opening of the bracket B3.

Reference numeral 5 is an air guide made of synthetic resin,
The thin-walled dip portion 5a is provided at a substantially central portion so as to gradually incline toward the central portion along the slant portion of the groove 4b on the outer periphery of the bearing housing 4a, and the thin-walled dip portion 5a is formed in the bearing housing. It is fixed to the bracket A4 by a mounting screw 6 in a state of being pressed against and in close contact with the bottom of the groove 4b on the outer periphery of 4a.

Reference numeral 7 denotes a rotary fan arranged outside the air guide 5 and fixed to the rotor shaft 2b of the rotor 2. The rotary fan 7 has an intake port 7a in the central portion and a discharge port 7b in the outer peripheral portion. 8
Is a fan case that covers the air guide 5 and the rotary fan 7, and is attached to one end opening side of the bracket B3.

The operation and assemblability of the electric blower configured as described above will be described below.

First, the operation will be described. When power is applied to the electric blower, the rotor 2 is energized via the stator 1 and the brush, and the rotor 2 rotates at a high speed. When the rotor 2 rotates, the fan 7 fixed to the shaft 2b rotates at high speed, so that air is sucked from the suction port 8a of the fan case 8. Next, the sucked high-pressure air is guided through the intake port 7a and the discharge port 7b of the rotary fan 7 into the bracket B3 via the air guide 5, and cools the stator 1 and the rotor 2 to the outside. Is discharged.

Since the high pressure air introduced into the air guide 5 is confirmed to be tight between the groove 4b and the dip portion 5a of the air guide 5, the bracket B3 is used.
The air inside does not leak to the fan 7 side and is smoothly guided into the bracket B3. Therefore, it is possible to prevent a decrease in performance due to a decrease in air pressure.

Assembling will now be described. Since the structure does not ensure tightness by fitting between the outer peripheral portion of the bearing housing 4a of the bracket A4 and the thin dip portion 5a of the air guide 5, the air guide 5 is not used. It is possible to easily assemble without the need for fitting and inserting, and the assembling property is also improved.

[0017]

As described above, according to the present invention, a thin-walled dip portion is formed so as to gradually incline toward the central portion of the air guide along the inclined portion of the groove on the outer periphery of the bearing housing. The thin-walled dip portion is brought into contact with the bottom portion of the groove on the outer periphery of the bearing housing of the bracket A, and the thin-walled dip portion is fixed to the outer periphery of the bearing housing when the air guide and the bracket A are fixed with a mounting screw. By tightly contacting the bottom of the groove with the air, the tightness of the air can be ensured and the suction performance can be improved and stabilized.

Further, since it is not necessary to make the dimensions of the air guide inner hole portion and the outer peripheral portion of the bearing housing to be fitting dimensions from the aspect of tightness as in the conventional case, it is possible to easily assemble,
The assemblability can also be improved.

As described above, according to the present invention, great practical effects can be obtained.

[Brief description of drawings]

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

FIG. 2 is an enlarged view of a main part of the one-sided sectional view shown in FIG.

FIG. 3 is a partially enlarged view of an air guide in the electric blower of the present invention.

[Explanation of symbols]

 1 Stator 2 Rotor 3 Bracket B 3b Flat part 4 Bracket A 4a Bearing housing 4b Groove 5 Air guide 5a Dip part 6 Mounting screw 7 Rotating fan 8 Fan case

Claims (3)

[Claims] 1. A stator, a rotor disposed inside the stator, and a flat surface portion projecting to the outside of the cylindrical portion at one opening edge of the cylindrical portion for housing the rotor. Bracket B, a bracket A having a bearing housing for holding the rotor, fixed to the flat surface of the bracket B by covering one end opening of the bracket B, and a rotary fan fixed to the shaft of the rotor. And an air guide that guides the air discharged from the fan into the bracket B, and a fan case that covers the air guide and the fan and is attached to one end opening side of the bracket B,
An electric blower characterized in that the air guide has a thin-walled dip portion projecting toward the center portion at a substantially central portion, and the dip portion is brought into close contact with a bottom portion of a groove on an outer periphery of the bearing housing. 2. The electric blower according to claim 1, wherein the dip portion is gradually inclined toward the center along the inclined portion of the groove on the outer circumference of the bearing housing A. 3. The electric blower according to claim 1, wherein the dip portion is brought into close pressure contact with the outer periphery of the rib on the bottom of the groove on the outer periphery of the bearing housing by tightening a mounting screw for holding and fixing the air guide.