JP2000045996A - Electrodynamic fan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit loss due to air flow turbulence at the resin inducer, particularly impact loss of the tip portion of the inlet, and inhibit turbulence of the flow of the internal duct. SOLUTION: The thickness of a blade portion 25a of a resin inducer 25 is made approximately the same thickness as a sheet metal blade 24 at the connecting portion thereof so that they connect smoothly, gradually becoming thinner toward the inlet 23a side. Therefore the impact with the blade is small at the tip portion of the inlet 23a, and further, the sheet thickness gradually becomes equivalent to that of the sheet metal blade 24. As a result, the air is able to flow smoothly, inhibiting loss and enabling high intake performance to be achieved.

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 a vacuum cleaner for sucking dust.

[0002]

2. Description of the Related Art In recent years, electric vacuum cleaners have tended to increase the output of electric blowers in order to effectively perform carpet cleaning and the like.

A conventional electric blower will be described below with reference to FIG.
This will be described with reference to FIG. FIG. 8 is a partially cut-away side view of an electric blower including an impeller, a fan case, and a motor.
FIG. 9 (a) is a perspective view of the impeller with a part of the impeller removed, and FIG. 9 (b)
Is the cross-sectional shape of the inducer blade.

In FIGS. 8 and 9, reference numeral 1 denotes an impeller main body. Reference numeral 2 denotes a sheet metal rear shroud, and a sheet metal front shroud 3 is disposed so as to face the shroud 2, and a gap is provided between the shrouds 2 and 3. Reference numeral 4 denotes a plurality of sheet metal blades sandwiched between the pair of shrouds 2 and 3. Reference numeral 5 denotes an intake port 3a (also serving as an intake port of the impeller body 1) provided at the center of the front shroud 3. This is an inducer for rectifying the airflow from the intake port 3a, and it is necessary to enhance the rectifying action in terms of increasing the output of the electric blower. Therefore, the shape of the inducer 5 is a three-dimensional curved surface.

The inducer 5 comprises a substantially conical hub 6 and a blade 5a formed thereon. Projections 4a are provided on the upper surface and the lower surface of each sheet metal blade 4, respectively, and the protrusions 4a are inserted into holes provided in the front shroud 3 and the rear shroud 2, and the tips of the protrusions 4a are crushed ( Caulking), and the sheet metal blade 4 is sandwiched between the shrouds 2 and 3. As described above, the shrouds 2 and 3 and the blades 4 which are the main parts of the impeller body 1 are made of sheet metal. I have to.

Further, the blade 5a of the resin inducer 5
Has almost the same thickness as the blade 4 made of sheet metal, and the joint portion with the hub 6 has only a very small arc generated by molding.

Reference numeral 8 denotes a motor for driving the impeller body 1;
Reference numeral 9 denotes an air guide, and the air that has flowed in the outer peripheral direction of the impeller main body 1 through the air guide 9 flows into the motor 8 side. Reference numeral 10 denotes a fan case which includes the impeller main body 1 and the air guide 9 and is hermetically attached to the outer periphery of the motor 8 and has a suction hole at the center thereof.

The operation of the above configuration will be described. The impeller main body 1 rotates at a high speed, and the air flow is sucked from the intake port 3a of the impeller main body 1. It passes between the blades 4 and is discharged from the outer periphery of the impeller body 1. Further, the air flow passes through the air guide 9 and the motor 5
It is discharged inside.

[0009]

In the electric blower described above,
The blade part 5a of the resin inducer 5 is a sheet metal blade 4
Because of the same thickness, the plate thickness at the tip of the blade portion 5a is large, and a large collision loss occurs. Further, even if only the tip of the blade portion is made thin, the thickness rapidly increases thereafter, and the flow is disturbed and loss occurs.

SUMMARY OF THE INVENTION It is an object of the present invention to suppress a loss due to a turbulence of an air flow in a resin-made inducer, in particular, a collision loss at a tip portion of an intake port and a turbulence of a flow in an internal passage.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a resin inducer having a blade having a thickness substantially equal to that of a sheet metal blade at a connecting portion with the sheet metal blade. Since it gradually thinned toward the intake port side, there was little collision with the blade at the tip of the intake port, and the plate thickness gradually became equal to the sheet metal blade,
The air flow flows smoothly, reducing the occurrence of losses. In addition, since the thickness of the blade portion is reduced, the area of the internal passage can be effectively used, so that the degree of freedom of the blade shape is increased, and a shape in which the turbulence of the airflow is further suppressed can be realized.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION
Equipped with an electric motor and an impeller rotated by the electric motor,
The impeller is provided with a front shroud having an intake port, a rear shroud arranged at a distance from the front shroud, a plurality of sheet metal blades sandwiched by the shrouds, and an intake port side of the impeller. It is composed of a resin-made inducer that rectifies the intake airflow, and the blade thickness of the inducer is approximately equal to the thickness of the connection portion of the sheet metal blade, and is gradually reduced toward the intake port side. is there.

[0013] In this configuration, since the tip of the intake port of the blade of the resin-made inducer is thin, collision loss is suppressed. Further, the thickness gradually increases up to the sheet metal blade, and since the thickness of the connection portion is substantially the same as that of the sheet metal blade, the air flow smoothly flows to suppress the occurrence of loss.

According to a second aspect of the present invention, there is provided an electric motor, an impeller rotated by the electric motor, wherein the impeller is provided with a front shroud having an intake port, and a rear surface arranged at a distance from the front shroud. Shroud,
A plurality of sheet metal blades sandwiched between these shrouds, and a resin-made inducer provided on the intake port side of the impeller to rectify intake air flow, wherein the inducer is provided with an intake blade portion on the intake port side. And the connection blades on the connection side.

With this configuration, the intake airflow can be rectified by the intake blades, and can be smoothly connected to the sheet metal blade by the connection blades. The loss due to turbulence in the flow at the connection between the inducer and the sheet metal blade is suppressed.

The invention described in claim 3 of the present invention is the same as that in claim 2
Since there is a substantially triangular blade portion between the intake blade portion and the connection blade portion and between the front shroud and the front shroud, there is no gap between the resin-made inducer and the front shroud. High pressure recovery can be achieved.

According to a fourth aspect of the present invention, there is provided an electric motor, an impeller rotated by the electric motor, wherein the impeller is provided with a front shroud having an intake port, and a rear surface arranged at a distance from the front shroud. Shroud,
A plurality of sheet metal blades sandwiched by these shrouds, and a resin inducer provided on the intake port side of the impeller and rectifying the intake air flow, the inducer includes a plurality of blades, A conical hub portion and a substantially arc-shaped fillet portion provided at a connection portion between the conical hub portion, and the fillet portion is a substantially arc having the smallest connection portion between the blade side and the sheet metal blade. It is what it was.

In this configuration, the air flow smoothly flows along the fillet portion, and the fillet portion near the intake port has a small substantially circular arc, so that collision loss does not occur. Since the connection portion also has a small substantially circular arc, the air flow smoothly flows without peeling to the sheet metal blade on which the fillet portion cannot be formed, thereby suppressing the occurrence of loss.

The invention according to claim 5 of the present invention is directed to claim 4
Since the described fillet portion is formed to have a substantially circular arc gradually large immediately before the connection portion with the sheet metal blade, the air flow particularly near the intake port is smoothly reduced to suppress the occurrence of loss.

The invention according to claim 6 of the present invention is the invention according to claim 4.
Since the described fillet portion has a substantially circular arc size different on the back surface of the inducer blade portion, the passage area is not narrowed more than necessary, and the substantially circular arc is not reduced, and the turbulence of the air flow is suppressed. Flows smoothly.

According to a seventh aspect of the present invention, there is provided an electric motor, an impeller rotated by the electric motor, wherein the impeller is provided with a front shroud having an intake port, and a rear surface arranged at a distance from the front shroud. Shroud,
A plurality of sheet metal blades sandwiched by these shrouds, and a resin-made inducer provided on the intake port side of the impeller to rectify intake airflow, wherein the inner end of the inducer has an outer peripheral side. It is arranged forward in the rotational direction from the tip.

With this configuration, the length of the resin-made inducer blade can be increased without substantially reducing the intake area perpendicular to the air flow, and the air flow is smoother in a short range up to the sheet metal blade. Flows to

[0023]

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

Embodiment 1 FIG. 1 shows a first embodiment of the present invention.
This will be described below. Since the mounting configuration of the impeller body and the motor is the same as the conventional configuration, detailed description thereof is omitted. Since the feature of the present embodiment resides in the impeller body, it will be described in detail below. FIG. 1A is a partially cutaway perspective view of the impeller, and FIGS. 1B to 1D are schematic views of the cross-sectional shapes of the inducer blade portions A, I, and U, respectively.

In FIG. 1, reference numeral 21 denotes an impeller body, which is sandwiched between a rear shroud 22 made of sheet metal, a front shroud 23 made of sheet metal arranged at a distance from the rear shroud 22, and a pair of shrouds 22, 23. A plurality of sheet metal blades 24 and a resin inducer 25 provided corresponding to an air inlet 23 a provided at the center of the front shroud 23. The sheet metal blade 24 is attached to each of the shrouds 22 and 23 by caulking in the same manner as in the conventional arrangement. The resin-made inducer 25 includes a substantially conical hub 25b and a blade 25a formed on the hub 25b.
In order to rectify the air flowing from 3a to the sheet metal blade 24 side, the shape of the blade portion 25a is a shape having a three-dimensional curved surface.
It is preferable that the resin be formed by resin molding.

In the blade portion 25a of the resin-made inducer 25, a is a front end portion on the intake side, a is an intermediate portion, and c is a connection portion with the sheet metal blade. It has a thickness equal to or greater than that, the tip portion a is thinner than the connection portion c, and the middle portion a is a middle thickness between the tip portion a and the connection portion c. As described above, the blade portion 25a has a small thickness at the tip portion and gradually increases in thickness.
4 and the thickness of the sheet metal blade 2
4 is connected.

The operation in the above configuration will be described. The impeller main body 21 rotates at a high speed and the impeller main body 2 rotates.
The airflow is sucked from the first air inlet 23a. This air flow passes through an internal passage surrounded by the front shroud 23 and the resin inducer 25, and subsequently, the front and rear shrouds 23.2
2 and an internal passage surrounded by a sheet metal blade 24,
It is discharged from the outer periphery of the impeller body 21. At this time, the air flow is less likely to collide because the tip of the blade portion 25a of the resin inducer 25 on the suction side is thin, and the internal flow is smooth because the plate thickness gradually changes to the thickness of the sheet metal blade 24. And collision is less likely to occur at the connection point.

As described above, according to the impeller for the electric blower of the present embodiment, the blade thickness of the resin-made inducer 25 is adjusted at the connection portion with the sheet-metal blade 24.
4, the connection is smoothly made at substantially the same thickness as that of the sheet metal blade 4 and the thickness of the sheet metal blade is gradually reduced toward the intake port side.
Since the air flow becomes equal to 4, it is possible to obtain a high suction performance by smoothly suppressing the flow of the air flow.
In addition, since the thickness of the blade portion 25a is reduced, the area of the internal passage can be effectively used, the degree of freedom of the blade shape can be increased, and a shape in which the turbulence of the airflow is further suppressed can be realized.

(Embodiment 2) FIG. 2 shows a second embodiment of the present invention.
And FIG. Since the basic configuration of the impeller body is the same as that of the above-described embodiment, the same components are denoted by the same reference numerals, detailed description thereof will be omitted, and a sheet metal blade and a resin The connection with the inducer will be described in detail below.

FIGS. 2A and 3A are partially cutaway perspective views of the impeller, and FIGS. 2B and 3B are partially enlarged views of the inducer portion.

In FIG. 2, the blade 25a of the resin-made inducer 25 is composed of a suction blade 35 on the suction port 23a side and a connection blade 36 disposed on the connection side with the blade 24 made of sheet metal. Here, the intake blade portion 35 is
It is led to the inside with a gentle curve from the a side,
Further, the connecting blade portion 36 is smoothly connected to the sheet metal blade.

The operation in the above configuration will be described. The impeller main body 21 rotates at high speed and the impeller main body 2 rotates.
The airflow is sucked from the first air inlet 23a. This air flow passes through an internal passage surrounded by the front shroud 23 and the resin inducer 25, and subsequently, the front and rear shrouds 23.2
2 and an internal passage surrounded by a sheet metal blade 24,
It is discharged from the outer periphery of the impeller body 21. At this time, the air flow flows in from the tip of the intake blade portion 35 of the blade portion 25a of the resin inducer 25, and flows inside while being rectified along a gentle curve, and then smoothly flows from the connection blade portion 36 to the sheet metal blade. Flows.

As described above, according to the impeller for an electric blower of the present embodiment, the blade portion 25a of the resin-made inducer 25 is provided.
Is composed of the intake blade portion 35 and the connection blade portion 36, so that the air flow smoothly flows in the vicinity of the intake port 23a of the resin-made inducer 25 and at the connection portion with the sheet metal blade 24 to suppress the occurrence of loss. High suction performance can be obtained.

As shown in FIG. 3, the substantially triangular blade portion 3 is in contact with the intake blade portion 35 and the connection blade portion 36 and fills a gap with the front shroud 23 having a sharp change in curvature.
The provision of 7 enables smooth recovery of pressure without air flow leaking from the gap, and also enables smooth flow of airflow near the joint between front shroud 23 and resin-made inducer 25.

(Embodiment 3) FIG. 4 shows a third embodiment of the present invention.
This will be described with reference to FIG. Since the basic configuration of the impeller body is the same as that of the first embodiment, the same components are denoted by the same reference numerals and detailed description thereof will be omitted.
Hereinafter, the connection portion between the sheet metal blade and the resin inducer, which is a characteristic portion of the present embodiment, will be described in detail.

4A to 6A are partially cutaway perspective views of the impeller, and FIGS. 4B to 6D are schematic views of the cross-sectional shapes of the inducer blade portions A, I, and U, respectively.

In FIG. 4, a substantially arcuate fillet 38 is provided at the connection between the blade 25a and the hub 25b of the resin-made inducer 25, and the tip of the blade 25a on the side of the air inlet 23a and the sheet metal. At the outermost peripheral end, which is the connection portion with the blade 24, the fillet is a very small arc-shaped fillet having a substantially circular arc that is larger toward the middle of the blade portion 25a.

In this configuration, the air flow near the connection between the blade portion 25a and the hub 25b of the resin-made inducer 25 flows along the substantially arc-shaped fillet portion 38, and at the tip of the intake port 23a, the fillet is formed. Sheet metal blade 2 that cannot form fillet portion 38 without colliding with portion 38
No. 4 is connected smoothly to prevent peeling and turbulence.

Further, by providing the fillet portion 38, the strength of the connecting portion between the blade portion 25a rotating at high speed and the hub 25b is increased, and the plate thickness of the blade portion 25a itself is reduced to reduce the collision loss at the tip portion. Reduction and securing of the internal passage area can be performed.

In FIG. 5, (e) is a schematic diagram of a cross-sectional shape of the blade portion d, and the fillet portion 38 is
At the tip of the 3a side, a very small arc is formed.
By gradually increasing the substantially circular arc until just before the connecting portion with the connecting portion, and forming a very small substantially circular arc at the connecting portion, the turbulence of the air flow in the fillet portion 38 can be further suppressed.

As shown in FIG. 6, the substantially circular arc of the front side fillet portion 38a is enlarged, and the rear side fillet portion 38b is enlarged.
By arranging the substantially circular arcs small, it is possible to configure the fillet portion 38 without greatly reducing the internal passage area, and the flow smoothly flows without generating the turbulence of the air flow due to the reduced area.

(Embodiment 4) FIG. 7 shows a fourth embodiment of the present invention.
This will be described below. Since the basic structure of the impeller body is the same as that of the first embodiment, the same components are denoted by the same reference numerals, detailed description thereof will be omitted, and a sheet metal blade which is a feature of this embodiment will be described. Hereinafter, a connection portion between the resin and the resin inducer will be described in detail.

FIG. 7 (a) is a partially cutaway perspective view of the impeller, and FIG. 7 (b) is a partially enlarged view of the inducer blade.

In FIG. 7, the blade 25a of the resin impeller 25 is such that the inner peripheral end A on the intake port 23a side is disposed forward of the outer peripheral end B by an angle θ in the rotational direction.

As described above, according to the impeller for an electric blower of the present embodiment, the blade length of the resin-made inducer 25 can be increased without substantially reducing the area of the intake port 23a. The air flow gradually changes in a short range up to the blade 24, so that the air flows more smoothly and high suction performance can be obtained.

[0046]

According to the first aspect of the present invention, the thickness of the blade of the resin-made inducer is smoothly connected at the connection portion with the sheet-metal blade at substantially the same thickness as that of the sheet-metal blade. Side, the collision with the blades is small at the tip of the intake port, and the plate thickness gradually becomes smaller with the sheet metal blade 24. Suction performance can be obtained. In addition, since the thickness of the blade portion is reduced, the area of the internal passage can be effectively used, so that the degree of freedom of the blade shape is increased, and a shape in which the turbulence of the airflow is further suppressed can be realized.

According to the second aspect of the present invention, since the blade of the resin-made inducer is composed of the suction blade and the connection blade, the vicinity of the air-intake port of the resin-made inducer and the blade made of sheet metal can be improved. Air flow smoothly at the connection point,
High suction performance can be obtained while suppressing occurrence of loss.

According to a third aspect of the present invention, a substantially triangular blade portion is provided which is in contact with the intake blade portion and the connection blade portion and fills a gap with the front shroud having a sharp change in curvature. The pressure can be smoothly recovered without the flow leaking from the gap, and the airflow flowing near the joint between the front shroud and the resin-made inducer can flow smoothly.

According to a fourth aspect of the present invention, the air flow near the connecting portion between the blade and the hub of the resin-made inducer flows along the substantially arc-shaped fillet portion, and the air inlet-side tip portion. In this case, without colliding with the fillet portion, it is smoothly connected to a sheet metal blade that cannot form the fillet portion, thereby suppressing peeling and turbulence.

Further, by providing a fillet portion, the strength of the connecting portion between the blade portion rotating at high speed and the hub is increased, and the thickness of the blade portion itself is reduced to reduce the collision loss at the tip portion, and the internal passage. The area can be secured.

According to a fifth aspect of the present invention, the fillet portion is formed as a very small arc at the front end portion on the intake port side, and the arc is gradually enlarged until immediately before the connection with the sheet metal blade. In this case, the turbulence of the air flow at the fillet portion can be further suppressed by forming the arc into a very small arc.

In the invention according to claim 6 of the present invention, the fillet portion has a substantially circular arc of the front side fillet portion and a small circular arc of the rear side fillet portion, so that the internal passage area is not greatly reduced. A fillet portion can be formed, and the air flows smoothly without generating airflow turbulence due to area reduction.

According to the seventh aspect of the present invention, it is possible to secure a long blade length of the resin-made inducer blade without substantially reducing the area of the intake port, and to gradually reduce the length of the blade to the sheet metal blade. The air flow changes its flow, and can flow more smoothly to obtain high suction performance.

[Brief description of the drawings]

FIG. 1 (a) is a partially cutaway perspective view of an impeller for an electric blower according to a first embodiment of the present invention; FIG. 1 (b) is a schematic cross-sectional view of a portion of an impeller of an impeller of the impeller; Cross-sectional shape schematic diagram (d) Cross-sectional shape schematic diagram of the same c portion

FIG. 2A is a partially cutaway perspective view of an impeller for an electric blower according to a second embodiment of the present invention. FIG. 2B is a partially enlarged view of an inducer portion of the impeller.

FIG. 3 (a) is a perspective view of the impeller with a part of the impeller partially removed.

FIG. 4 (a) is a partially cutaway perspective view of an impeller for an electric blower according to a third embodiment of the present invention; (b) a schematic cross-sectional view of a location of an inducer blade portion of the impeller of the impeller; Cross-sectional shape schematic diagram (d) Cross-sectional shape schematic diagram of the same c portion

5 (a) is a perspective view of the impeller, with a partial cut-away; (b) a schematic view of a cross-sectional shape at a location of an inducer blade portion of the impeller; (c) a schematic view of a cross-sectional shape at a location of the same impeller; Schematic diagram (e) Schematic diagram of cross-sectional shape at the same location

FIG. 6A is a partially cutaway perspective view of the impeller. FIG. 6B is a schematic cross-sectional view of a section A of an inducer blade of the impeller. FIG. 6C is a schematic cross-sectional view of a section A of the impeller. Schematic diagram

FIG. 7A is a partially cutaway plan view of an impeller for an electric blower according to a fourth embodiment of the present invention. FIG. 7B is a partially enlarged view of an inducer blade portion of the impeller.

FIG. 8 is a side view of a part of a conventional electric blower with a part removed.

9A is a partially cutaway perspective view of a conventional impeller for an electric blower, and FIG. 9B is a schematic cross-sectional view of an inducer blade portion of the impeller.

[Explanation of symbols]

 21 Impeller Body 22 Rear Shroud 23 Front Shroud 23a Inlet 24 Sheet Metal Blade 25 Resin Inducer 25a Blade 25b Hub 35 Intake Blade 36 Connection Blade 37 Substantially Triangular Blade 38 Fillet 38a Front Fillet 38b Rear Side fillet

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Go Nishimura 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F-term (reference) 3H033 AA02 BB02 BB06 BB20 CC01 DD01 DD06 DD23 DD26 DD30 EE08 EE19

Claims (7)

[Claims] 1. An electric motor, comprising an impeller rotated by the electric motor, wherein the impeller is sandwiched between the front shroud having an intake port, a rear shroud arranged at a distance from the front shroud, and the shroud. A plurality of sheet metal blades and a resin inducer provided on the intake port side of the impeller and rectifying the intake air flow, and the blade thickness of the inducer is substantially the same at the connection part of the sheet metal blade. The electric blower has the same thickness as that of the air blower and is gradually thinner toward the intake port. 2. An electric motor, comprising an impeller rotated by the electric motor, wherein the impeller is sandwiched between the front shroud having an intake port, a rear shroud arranged at a distance from the front shroud, and the shroud. A plurality of sheet metal blades and a resin-made inducer provided on the intake port side of the impeller to rectify intake air flow, wherein the inducer includes an intake blade portion on the intake port side,
An electric blower comprising a connection blade on the connection side with the sheet metal blade. 3. The electric blower according to claim 2, wherein the inducer has an intake blade portion, a connection blade portion, and a substantially triangular blade portion which is in contact with both of them and fills a gap with the front shroud. 4. An electric motor, comprising an impeller rotated by the electric motor, wherein the impeller is sandwiched between the front shroud having an intake port, a rear shroud arranged at a distance from the front shroud, and the shroud. A plurality of sheet metal blades and a resin inducer provided on the intake port side of the impeller to rectify the intake air flow, the inducer includes a plurality of blades and a substantially conical hub. An electric blower comprising a substantially arc-shaped fillet portion provided at a connection portion between the two, wherein the fillet portion has a substantially arc shape at which a connection portion between the blade portion and the sheet metal blade is the smallest. 5. The electric blower according to claim 4, wherein the fillet portion is formed such that a substantially circular arc is gradually increased from an intake port side of the blade portion to a portion immediately before a connection portion with the sheet metal blade. 6. The electric blower according to claim 4, wherein the fillet portion has a substantially circular arc size different on the back surface of the inducer blade portion. 7. An electric motor, comprising an impeller rotated by the electric motor, wherein the impeller is sandwiched between the front shroud having an intake port, a rear shroud arranged at a distance from the front shroud, and the shroud. A plurality of sheet metal blades and a resin-made inducer provided on the intake port side of the impeller to rectify intake airflow, wherein the inducer has an inner peripheral end portion that is rotated in a rotational direction from an outer peripheral end portion. Electric blower arranged in front.