JP2000337295A - Electric blower and vacuum cleaner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric blower high in suction capacity to increase pressure recovering efficiency of a diffuser part of an air guide and a vacuum cleaner using it. SOLUTION: As a diffuser part 10 constituted between neighbouring stationary blades is formed on an air guide 5, and R is formed on each of interior angles of four points of a cross-section vertical against a flow of the diffuser part 10, an air current discharged from an impeller 4 smoothly flows without stagnation at the time of flowing at the diffuser part of the air guide 5, and accordingly, there is little channel loss and pressure recovery is smoothly carried out during that time, and it is possible to provide high suction performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electric blower used for a vacuum cleaner or the like.

[0002]

2. Description of the Related Art In recent years, an electric vacuum cleaner using an electric blower has been tending to have a high output in order to effectively perform carpet cleaning and the like.

A conventional electric blower will be described below with reference to FIG.
-It will be described based on FIG. 11 and FIG.

FIG. 10 is a partially cutaway plan view of an electric blower, FIG. 11 is a rear view of a fan portion, and FIG. 12 is a partially cutaway sectional view of the electric blower. (B) of FIG.
(A) It is an enlarged view of N part of a figure. In FIGS. 10, 11 and 12, reference numeral 1 denotes a fan case, which has an intake hole 2 in the upper central portion, and is attached to the bracket B 3 of the motor unit 8 by press fitting. An impeller 4 having a plurality of blades 14 and an air guide 5 having a stationary blade 13 on its surface are provided inside the fan case 1. Reference numeral 10 denotes a diffuser portion formed between the adjacent stationary blades, 11 denotes a flow changing portion for guiding the airflow flowing out of the diffuser portion to the back surface of the air guide 5, and 12 denotes a subsequent return passage portion.
The return passage portion 12 is partitioned by return passage guide vanes 15. Reference numeral 6 denotes a motor shaft, and the impeller 4 is attached to the motor shaft 6 by tightening with a nut 7.
Arrows indicate the direction of rotation of the impeller, and arrows indicate the flow of air.

[0005] In the above configuration, the flow of air will be described. An air flow is generated by rotating the impeller 4, and the flow path is “inlet 2 → inside of impeller 4 → air guide 5”. The inside of the motor is cooled from the diffuser unit 10 through the flow changing unit 11, the return passage unit 12 and the motor unit 8 in this order, and is discharged to the outside.

[0006]

However, in such a conventional configuration, since the diffuser portion 10 is formed by the bottom surface of the air guide 5, the stationary blades 13, and the fan case 1, the cross-sectional shape of the diffuser portion 10 is substantially rectangular. The air flow was stagnant at the inner corners, and the loss was large. In order to eliminate such a loss, there is also a type in which an R is provided between the bottom surface of the air guide 5 and the stationary blade 13, which improves the pressure recovery efficiency in the diffuser unit 10 slightly, but reduces the fan case. No such consideration was given to the inner corner formed by the stator blade 1 and the stationary blade 13. In the case where the cross-sectional shape is a rectangular shape that is short in the direction of the motor shaft 6, a vortex secondary flow is generated in the diffuser portion 10, which may be a loss. Furthermore, the fan case 1 is normally press-fitted into the bracket B3 of the motor unit 8 in the final step of assembly, but when press-fitting is incomplete or the like, a gap is created between the fan case 1 and the stationary blade 13, There is a possibility that the pressure recovery in the diffuser unit 10 may be reduced.

An object of the present invention is to provide an electric blower in which the pressure recovery efficiency of the diffuser portion 10 of the air guide 5 is enhanced and the suction capacity is enhanced, and an electric vacuum cleaner using the same.

[0008]

In order to achieve the above object, the present invention provides an impeller, a motor for driving the impeller to rotate, an air guide provided on the outer periphery of the impeller and having a plurality of stationary blades on its surface, A diffuser portion formed between adjacent vanes of the air guide, a flow changing portion for guiding an airflow discharged from the diffuser portion to the back surface of the air guide, and a plurality of return passage guide vanes arranged on the back surface of the air guide. It has a return passage that guides the air flow of the flow change section to the center of the back surface of the air guide, and an intake hole that introduces air to the impeller. And a fan case, wherein R is provided at three or more of four internal angles of a substantially rectangular cross section formed by cutting the diffuser section perpendicular to the direction of air flow. Thus, the static pressure recovery efficiency of converting the dynamic pressure component, which is largely contained in the airflow discharged from the impeller, into the static pressure in the diffuser portion of the air guide is improved, and the electric blower having high suction capability and the use thereof are used. An electric vacuum cleaner can be provided.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION
An impeller, a motor for rotating and driving the impeller, an air guide provided on the outer periphery of the impeller, and having a plurality of stationary blades on a surface, a diffuser portion formed between adjacent stationary blades of the air guide, and a diffuser portion. A flow changing portion that guides the discharged air flow to the back surface of the air guide, and a return passage portion that is partitioned by a plurality of return passage guide vanes disposed on the back surface of the air guide, and guides the air flow of the flow changing portion to the center of the back surface of the air guide. And a fan case having an air inlet for introducing air into the impeller, and including an air guide impeller and airtightly attached to the outer periphery of the motor bracket, and cutting the diffuser section perpendicularly to the direction of air flow. R is provided at three or more of the four internal angles of the substantially rectangular cross section formed by the above, so that the dynamic pressure component that is largely contained in the airflow discharged from the impeller can be reduced by the air. In which the static pressure recovery efficiency is improved to be converted into static pressure at the diffuser portion of the id.

In the invention according to claim 2 of the present invention, the radius R on the convex side (negative pressure side) of the diffuser portion bent in a substantially arc shape is set to be larger than the radius R on the concave side (pressure side). In addition, the flow path friction loss at the portion where the flow velocity is high in the diffuser is reduced, and high pressure recovery performance can be obtained.

In the invention according to claim 3 of the present invention, the cross section perpendicular to the flow of the diffuser portion bent in a substantially circular arc shape is made substantially elliptical in the direction of the radius of curvature of the diffuser portion. The pressure difference in the cross section of the flow path decreases,
The secondary flow accompanying this can be suppressed, and higher pressure recovery performance can be obtained.

In the invention according to claim 4 of the present invention, the cross section perpendicular to the flow of the diffuser portion is substantially circular. Therefore, in the case of an air guide or the like in which the diffuser portion is linearly arranged, The pressure distribution in the cross section of the flow path becomes uniform,
Higher pressure recovery performance can be obtained.

In the invention according to claim 5 of the present invention, the cross section perpendicular to the flow of the diffuser section is set so as to gradually increase from the entrance to the exit of the diffuser section, so that the cross sectional area increases. As the angle R becomes larger, the cross-sectional shape is maintained substantially similar, and the pressure can be uniformly and efficiently recovered from the inlet to the outlet of the diffuser portion.

According to the invention of claim 6 of the present invention, since a part or all of the top surface of the diffuser portion is formed by a fan case, the electric blower can be assembled by a conventional method, and high pressure recovery performance can be obtained. Obtainable.

According to a seventh aspect of the present invention, the passage from the diffuser inlet to the return passage outlet through the flow changing portion to the return passage outlet has a smooth inner surface, and the cross-sectional area perpendicular to the flow gradually increases. Since the passages are arranged in a substantially spiral shape, the passages are not sharply bent or the passage cross-sectional area does not suddenly expand, and the passage from the diffuser section entrance to the return passage exit is Pressure recovery can be performed uniformly throughout the process, and pressure recovery can be performed efficiently.

[0016]

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIG. In the figure, (b) is (a)
The same reference numerals are used to denote the same parts as in the conventional example, and description thereof is omitted. In FIG. 1, the air guide 5 is composed of two parts, an air guide main body 17 and an air guide top surface section 16, and the diffuser section 10 has a duct formed without using the inner surface of the fan case 1. An R is formed at each of four inner corners of the cross section perpendicular to the flow of the diffuser section 10.

The operation of the above configuration will be described. The impeller 4 rotates at a high speed, sucks airflow from the intake port 2, and this airflow passes through the inside of the impeller 4 and is discharged from the outer peripheral portion. The discharged air flow passes through the diffuser section 10 of the air guide 5, passes through the return path section 12 via the flow changing section 11, proceeds to the inside of the motor, cools the inside of the motor, and cools through the exhaust port 18 of the motor bracket B3. It is discharged outside. At this time, when the air flow flows through the diffuser portion 10 of the air guide 5, the flow is smooth and smooth without flow stagnation due to the Rs provided at four places in the cross section of the passage. , Pressure recovery is performed smoothly.

As described above, according to the electric blower of the present embodiment, the cross section perpendicular to the flow of the
By forming the R at each of the inner corners, the air flow becomes smooth, the turbulence of the air flow is reduced, the pressure is efficiently recovered, and high suction performance can be obtained.

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to FIGS. In addition, the first
The same reference numerals are given to the same components as those of the embodiment,
The description is omitted. Diffuser part 1 of air guide 5
0 is arranged in a substantially circular arc shape, and R is formed at each of four internal angles in a cross section perpendicular to the flow. Furthermore, the R
Is a convex side 19 of the diffuser portion 10 arranged in a substantially arc shape.
The upper and lower Rs on the side (closer to the outer periphery of the fan case) are set larger than the upper and lower Rs on the concave side 20 (impeller side).

The operation of the above configuration will be described. When the air flow discharged from the impeller 4 passes through the diffuser section 10 of the air guide 5, since the diffuser section 10 is arranged in a substantially arc shape, the pressure of the air flow in the cross section of the passage is reduced. And the pressure on the convex side 19 (the side close to the fan case) is low, and the flow velocity is high. For this reason, the frictional resistance in the pipe is likely to increase, but the cross section R on the outside of the passage is set to be larger, so that the air flow can easily flow smoothly.

As described above, according to the electric blower of the present embodiment, the upper and lower R of the convex side 19 of the diffuser section 10 are set to be larger than the upper and lower R of the concave side 20.
The air flow becomes smoother, the turbulence in the air flow is reduced, the pressure is efficiently recovered, and high suction performance can be obtained.

Embodiment 3 Next, a third embodiment of the present invention will be described with reference to FIGS. The same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. The diffuser portion 10 of the air guide 5 is arranged in a substantially arc shape, and has a substantially elliptical cross section perpendicular to the flow.

The air flow discharged from the impeller 4 passes through the diffuser section 10 of the air guide 5 when the diffuser section 10 is arranged in a substantially arcuate shape. Although the pressure on the side 19 (fan case side) decreases and the pressure distribution tends to be non-uniform, the difference in the pressure distribution hardly occurs because the cross-sectional shape of the diffuser section 10 is substantially elliptical in the vertical direction. Becomes closer to a uniform state, and the loss is reduced.

As described above, according to the electric blower of the present embodiment, since the cross-sectional shape perpendicular to the flow of the diffuser section 10 is substantially elliptical, a difference in pressure distribution in the diffuser hardly occurs. , Thereby preventing the secondary flow, reducing fluid loss and efficiently recovering pressure,
High suction performance can be obtained.

(Embodiment 4) Next, a fourth embodiment of the present invention will be described with reference to FIGS. The same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. FIG. 5 is a plan view of the air guide body 17 alone. The diffuser 10 has a substantially straight center line, and a plurality of diffusers are provided around the impeller 4.
The cross section perpendicular to the flow is substantially circular.

The air flow discharged from the impeller 4 passes through the diffuser section 10 of the air guide 5, but the diffuser section 10 operates as follows.
Has a substantially circular cross section, and the diffuser portion 10
As a whole, it has a substantially conical shape. In the case of such a linear diffuser, when the passage cross section is circular, the pressure in the passage cross section is distributed concentrically, there is no deviation, and the pressure recovery efficiency is the best.

As described above, according to the electric blower of the present embodiment, since the cross-sectional shape perpendicular to the flow of the diffuser section 10 is substantially circular, a difference in pressure distribution in the diffuser hardly occurs. Thereby, secondary flow can be prevented, fluid loss is reduced, pressure recovery is performed efficiently,
High suction performance can be obtained.

Embodiment 5 Next, a fifth embodiment of the present invention will be described with reference to FIG. The same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. FIG. 7A is a perspective view of an air guide for an electric blower, and a broken line in the figure shows one of a plurality of diffuser units 10 partitioned between adjacent stationary blades 13. b) is an enlarged perspective view of the diffuser section 10, in which R is provided at four inner angles, and the R is set so as to gradually increase from the entrance (section A) of the diffuser section 10 toward the exit (section B). Have been.

The operation of the above configuration will be described. The air flow discharged from the impeller 4 passes through the diffuser section 10 of the air guide 5 but is not diffused.
Is set so as to gradually increase from the entrance to the exit. Therefore, as the cross-sectional area increases, the size of R also increases, and the cross-sectional shape is substantially similar in the diffuser unit 10. It is kept constant, the rate of pressure recovery of the air flow becomes close to constant, and the loss can be reduced.

As described above, according to the electric blower of the present embodiment, since the cross-sectional shape perpendicular to the flow of the diffuser section 10 is substantially similar in the diffuser, it is possible to suppress the loss in the diffuser. Pressure recovery is performed efficiently, and high suction performance can be obtained.

(Embodiment 6) Next, a sixth embodiment of the present invention will be described with reference to FIG. The same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. As in the conventional example, the top surface of the diffuser portion 10 is constituted by the fan case 1, but the fan case 1 is subjected to unevenness processing, and combined with the air guide 5, the diffuser portion having an R at the inner corner 4. 10
Is composed.

The operation in the above configuration will be described. The impeller 4 rotates at a high speed, sucks airflow from the intake port 2, and this airflow passes through the inside of the impeller 4 and is discharged from the outer peripheral portion. The discharged air flow passes through the diffuser section 10 of the air guide 5, passes through the return path section 12 via the flow changing section 11, proceeds to the inside of the motor, cools the inside of the motor, and cools through the exhaust port 18 of the motor bracket B3. Is discharged to At this time, when the air flow flows through the diffuser portion 10 of the air guide 5, the flow is smooth and smooth without flow stagnation due to the Rs provided at four places in the cross section of the passage. , Pressure recovery is performed smoothly.

As described above, according to the electric blower of the present embodiment, since the top surface of the air guide 5 is constituted by the fan case 1 as in the conventional case, the number of parts of the air guide 5 is the same as in the prior art. The same configuration as 5 can be realized,
High suction performance can be obtained. Note that the fan case 1 is usually made by drawing a metal, but if it is formed by resin molding or the like, the accuracy of the contact surface with the air guide 5 is improved, and the airtightness is further maintained.

Embodiment 7 Next, a seventh embodiment of the present invention will be described with reference to FIG. The same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. FIG. 9 is a perspective view of an air guide for an electric blower, and a broken line in the figure indicates one of a plurality of diffuser portions 10 partitioned between adjacent stationary blades 13. In the air guide 5, a passage from the inlet of the diffuser unit 10 to the outlet of the return passage 12 through the flow changing unit 11 is formed as a conduit whose inner surface is smooth and whose cross-sectional area perpendicular to the flow gradually increases. The plurality of passages are disposed substantially spirally inside the air guide.

The operation in the above configuration will be described. The air flow discharged from the impeller 4 passes through the diffuser section 10 of the air guide 5 and flows through the flow changing section 11 and the return path section 12. Is continuous and can be regarded as one curved pipe, and the static pressure recovery of the air flow is efficiently performed.

As described above, according to the electric blower of this embodiment, the passage from the inlet of the diffuser unit 10 to the outlet of the return passage 12 through the flow changing unit 11 and the outlet of the return passage 12 has a smooth inner surface and is perpendicular to the flow. By using a pipe having a gradually increasing cross-sectional area, loss in the diffuser can be suppressed, pressure recovery can be performed efficiently, and high suction performance can be obtained.

[0037]

According to the first aspect of the present invention, by providing R at three or more inner angles of a cross section perpendicular to the flow of the diffuser portion of the air guide, the air flow becomes smoother, It is possible to efficiently convert the dynamic pressure component of the airflow discharged from the impeller into a static pressure, and to provide an electric blower having high suction performance.

In the invention according to claim 6 of the present invention, the top surface of the diffuser portion of the air guide is formed by a fan case as in the conventional case, so that the basic structure is the same as in the prior art, and R is added to the cross section of the diffuser passage. It can provide high suction performance and also reduce the number of parts.

According to the seventh aspect of the present invention, the passage from the diffuser inlet to the return passage outlet through the flow changing portion to the return passage outlet has a smooth inner surface and a sectional area perpendicular to the flow gradually increases. With a single pipe line, the sudden expansion from the diffuser section to the flow change section, which was conventionally large loss, and the complicated shape of the pipe line are improved, and the pressure recovery is performed efficiently, so high suction is achieved. An electric blower having high performance can be provided.

[Brief description of the drawings]

FIG. 1A is a partially cutaway sectional view of an electric blower showing a first embodiment of the present invention. FIG. 1B is a partially enlarged sectional view of the electric blower.

2A is a partially cutaway sectional view of an electric blower showing a second embodiment of the present invention. FIG. 2B is a partially enlarged sectional view of the electric blower.

FIG. 3 is a partially cutaway plan view of an electric blower showing a second and a third embodiment of the present invention.

FIG. 4A is a partially cutaway sectional view of an electric blower showing a third embodiment of the present invention. FIG. 4B is a partially enlarged sectional view of the electric blower.

FIG. 5 is a plan view of an air guide showing a fourth embodiment of the present invention.

6A is a partially cutaway sectional view of the electric blower, and FIG. 6B is a partially enlarged sectional view of the electric blower.

FIG. 7 (a) is a perspective view of an air guide showing a fifth embodiment of the present invention, and (b) is a partially enlarged perspective view of the air guide.

FIG. 8 (a) is a partially cutaway sectional view of an electric blower showing a sixth embodiment of the present invention, and (b) is a partially enlarged sectional view of the electric blower.

FIG. 9 is a perspective view of an air guide showing a seventh embodiment of the present invention.

FIG. 10 is a partially cutaway plan view of a conventional electric blower.

FIG. 11 is a rear view of a fan portion of the electric blower.

FIG. 12 is a partially cutaway sectional view of the electric blower.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fan case 2 Intake port 3 Bracket B 4 Impeller 5 Air guide 6 Motor shaft 7 Nut 8 Motor (part) 10 Diffuser part 11 Flow change part 12 Return passage part 13 Stator vane 14 Blade 15 Return passage guide vane 16 Air guide top part 17 Air guide body 18 Exhaust port 19 Convex side 20 Concave side

Continued on the front page (72) Inventor Yoshitaka Murata 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. DD24 EE08 EE12 EE18

Claims (8)

[Claims] An impeller, a motor for rotating the impeller, an air guide provided on an outer peripheral portion of the impeller and having a plurality of stationary blades on a surface, and a diffuser portion formed between adjacent stationary blades of the air guide. And a flow changing unit that guides the airflow discharged from the diffuser unit to the back of the air guide,
A return passage portion, which is partitioned by a plurality of return passage guide vanes disposed on the back surface of the air guide, and guides the air flow of the flow changing portion to the center portion of the back surface of the air guide, and an intake hole for introducing air to the impeller; and A fan case including an air guide impeller and hermetically attached to the outer periphery of the motor bracket; and three out of four inner corners of a substantially rectangular cross section formed by cutting the diffuser section perpendicularly to the direction of air flow. The electric blower provided with the air guide provided with the R at the above inner angles. 2. An inner surface of the diffuser portion bent in a substantially arc shape has a radius R on a convex surface side (negative pressure surface side) and an inner radius R on a concave surface side (pressure side).
The electric blower according to claim 1, wherein the blower is set larger. 3. The electric blower according to claim 1, wherein a cross section perpendicular to the flow of the diffuser portion bent in a substantially arc shape is a substantially elliptical shape thin in a radius direction of the curvature of the diffuser portion. 4. The electric blower according to claim 1, wherein the cross section perpendicular to the flow of the diffuser section is substantially circular. 5. The electric blower according to claim 1, wherein R of a cross section perpendicular to the flow of the diffuser portion is set to gradually increase from an inlet to an outlet of the diffuser portion. 6. The electric blower according to claim 1, wherein a part or all of the top surface of the diffuser is formed by a fan case. 7. A smooth passage from the inlet of the diffuser section to the return passage outlet through the flow changing section,
The electric blower according to claim 1, wherein each of the independent blowers has a gradually increasing cross-sectional area perpendicular to the flow, and the passage includes an air guide disposed substantially in a spiral shape. 8. An electric vacuum cleaner using the electric blower according to claim 1.