JP2000104699A - Electric blower and electric vacuum cleaner using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the aerodynamic performance of an impeller while lowering the air resistance of the impeller and sealing a clearance between a blade and a plate by integrally forming at least one of a front surface plate and a rear surface plate with the blade. SOLUTION: An impeller is formed of a front surface plate 52 having a suction port 51 in a top surface thereof, a rear surface plate 53 provided under the front surface plate 52 opposite to each other, and plural blades 54 arranged so as to be pinched between both the front and rear surfaces 52, 53. The front surface plate 52, the rear surface plate 53 and the blades 54 form plural air discharge ports 55. Since the front surface plate 52 is integrally formed with the blade 54, a fastening projection for fixing the front surface plate 52 to the blade 54 is not formed in the top surface of the front surface plate 52, and air resistance in the top surface of the front surface plate 52 is lowered, and since a clearance is not generated between the front surface plate 52 and the blade 54, air-tightness is increased so as to improve the aerodynamic performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electric blower and an electric vacuum cleaner using the electric blower.

[0002]

2. Description of the Related Art An impeller used in a conventional electric blower has a front plate having a suction port at a central portion, a rear plate arranged to face the front plate, and
It consisted of blades arranged to be sandwiched between a front plate and a rear plate. The blade is provided with a plurality of crimping protrusions, which are inserted into square holes formed in the front plate and the rear plate, and the portions protruding from the front plate and the rear plate are crushed and crimped. Thereby, it was fixed to the front plate and the rear plate. These components were all formed of an aluminum alloy. The impeller assembled in this way is fixed to the rotating shaft of the electric motor by screws. Further, a fan casing is disposed above the impeller, and constitutes an electric blower.

[0003] Electric blowers used in recent vacuum cleaners are designed to have a stronger suction force and to be smaller and lighter.
By increasing the rotation speed of the electric blower, the efficiency and size of the electric blower are improved.

In the conventional impeller of the electric blower, as described above, the caulked portion of the blade remains protruding from the surfaces of the front plate and the rear plate. The caulked portion becomes an air resistance, causing a decrease in performance.

[0005] In addition, the structure formed by pressing or the like made of a thin metal plate such as aluminum tends to cause a gap between the contact surfaces of the blade and the front and rear plates, and this gap has also been a factor of deteriorating the performance of the impeller.

In order to solve this problem, for example, Japanese Patent Laid-Open
As described in JP-A-1-310198, a technique for reducing the air resistance by rounding the corners of the end of the caulking projection, and in JP-A-9-126185, the contact surface is painted or bonded. There has been proposed a technique for sealing a gap between the two.

[0007]

However, in the technique described in Japanese Patent Application Laid-Open No. Hei 1-310198, the corner of the end of the caulking projection is rounded to reduce air resistance. Since the caulked portion of the blade protrudes from the surfaces of the front plate and the rear plate, air resistance of the protruding portion exists.

Further, the seal by coating or bonding disclosed in Japanese Patent Application Laid-Open No. 9-126185 has problems in that the production cost is increased, and the heat resistance and strength of the paint and adhesive used are problematic.

Further, when increasing the rotation speed of the electric blower, since the rotational stress applied to the impeller during rotation increases, it is necessary to improve the rigidity of the entire impeller.
In the conventional impeller, it is assembled by caulking, and since the caulked portion is lower in strength than the plate and the blade base material, the rigidity of the entire impeller is low in the assembly by caulking,
There is a limit to the increase in rotation speed.

Furthermore, when the rotation speed of the electric blower increases, the rotational vibration due to the unbalance of the impeller increases, so that it is necessary to improve the balance accuracy of the impeller.
In a conventional structure in which a plurality of blades are caulked to a plate, the mounting accuracy is added to the dimensional accuracy of the component itself, so that the balance accuracy after assembling tends to vary, and the correction amount is large.

Accordingly, an object of the present invention is to solve the above problems, reduce the air resistance of the impeller, seal the gap between the blade and the plate, improve the aerodynamic performance of the impeller, and improve the initial performance of the impeller. An object of the present invention is to provide an electric blower in which the amount of unbalance is reduced, the balance correction accuracy is improved, vibration is reduced, and the number of revolutions of the electric blower is improved, and a vacuum cleaner using the electric blower is provided.

[0012]

SUMMARY OF THE INVENTION To achieve the above object, the present invention is characterized by an electric motor housed in a housing, an impeller fixedly mounted on a rotating shaft of the electric motor, and an impeller. In an electric blower having a fixed guide blade disposed on the downstream side of the flow path of the car and a fan casing covering the impeller and the fixed guide blade, the impeller has a front plate having an inlet, and the front plate has A back plate disposed so as to face, and a plurality of blades disposed between the front plate and the rear plate, wherein at least one of the front plate or the rear plate and the blade are integrated. It was formed in a way. The balance accuracy was improved by additionally processing the inner circumference or outer circumference, or the inner circumference and outer circumference of the plate.

According to the present invention, since the impeller is integrally formed to eliminate the caulking projection,
Air resistance, noise, and the like due to the caulking projection can be reduced. Further, after the forming, the inner and outer diameters of the plate are additionally processed, thereby removing a molding gate portion and a burr generated on the inner and outer circumferences, and concentric accuracy of the inner and outer diameters can be improved. This reduced the amount of unbalance of the impeller and improved the balance accuracy.

As described above, when this impeller is used for an electric blower, the aerodynamic performance of the electric blower can be improved, high-speed rotation can be realized, and the size of the electric blower can be reduced. And a reduction in size and weight can be realized.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

First, FIG. 1 shows a longitudinal sectional view of an electric blower 1 used for a vacuum cleaner.

The electric blower 1 comprises a motor 2 and a blower 3. The motor 2 is a commutator motor, and a stator 22 housed in a housing 21 and an end bracket 32.
And a rotor 28, a brush 28 for making electrical connection with the rotor 23 during rotation, and a holder 29 for holding the brush 28 and fixing it to the housing 21.

The rotor 21 includes a rotating shaft 26 supported by bearings 24 and 25 held by the housing 21, an iron core 27 fixed to the rotating shaft 26, and a commutator 30. The commutator 30 has a plurality of commutator pieces on its circumferential surface, and each commutator piece is connected to a coil wound around the iron core 27.

The brush 28 is housed and held in a holder 29, pressed against a commutator 30 by a spring 31, and is in sliding contact with the commutator 30.

The end bracket 32 is formed with an air inlet 33 for introducing air from the blower 3 into the electric motor 2. A fixed guide blade 34 is arranged on the end bracket 32, and an impeller 35 is
6 is fixed to the rotating shaft 26. A suction port 38 is formed at the center of a casing 37 fixed to the outer periphery of the housing 21 by press-fitting.

When the motor 2 starts rotating, the rotor 23
Rotates, and the impeller 35 provided coaxially with the rotor 23 also rotates. When the impeller 35 rotates, the fan casing 37
The air flows in from the suction port 38 of the airbag, passes through the impeller 35 and the fixed guide vanes 34, and is exhausted from the air intake 33 to the electric motor 2 side.

Next, the structure of the conventional impeller 35 will be described with reference to FIG. The impeller 35 has a front plate 52 having a suction port 51 at a central portion, a rear plate 53 disposed to face the front plate 52, and a front plate 52 and a rear plate 53. It consisted of the blades 54 arranged. The blade 54 is provided with a plurality of caulking projections, and these projections are inserted into square holes formed in the front plate 52 and the rear plate 53, and the front plate 52 and the rear plate 53 are inserted.
The more protruding portion was crushed and swaged, thereby being fixed to the front plate 52 and the rear plate 53. These components are all formed of a thin plate-like aluminum alloy.

In the above-described conventional impeller 35, the caulked portion of the blade 54 remains protrudingly on the surfaces of the front plate 52 and the rear plate 53 as described above.
As the number of revolutions of the electric blower 1 increases, the protruding crimped portion becomes air resistance, causing a decrease in performance.

The structure formed by pressing or the like made of a thin metal plate such as aluminum is composed of the blade 54 and the front and rear plate 5.
A gap is easily formed in the abutment surfaces of the wheels 2 and 53, and this gap also causes a reduction in the aerodynamic performance of the impeller 35.

The configuration of the impeller 35 according to the present embodiment will be described with reference to FIGS.

FIG. 3 is an external perspective view of the impeller 35 according to the present embodiment, FIG. 4 is a plan view of the impeller 35 according to the present embodiment, and FIG. 5 is a longitudinal sectional view.

3, 4 and 5, the impeller 35 has a front plate 52 having a suction port 51 on the upper surface, a rear plate 53 provided below and facing the front plate 52, a front plate 52, It is composed of a plurality of blades 54 arranged so as to be sandwiched by the rear plate 53. The blade 54 is disposed so as to be curved on the front plate 52 and the rear plate 53 as shown in FIG. The plurality of air discharge ports 5 are formed by the front plate 52, the rear plate 53, and the plate 54.
5 are formed. The air sucked from the suction port 51 by the rotation of the impeller 35 is discharged from the air discharge port 55, guided to the electric motor side, cooled the electric motor 2, and then exhausted from the exhaust port of the cleaner body. .

The impeller 35 is required to rotate at high speed for high aerodynamic performance and small size and light weight. Impeller 35
In order to improve the aerodynamic performance, it is necessary to reduce the air resistance of the impeller 35 and improve the airtightness of the flow path in the impeller 35. Next, a structure for reducing air resistance and improving airtightness of the flow path will be described.

In this embodiment, as shown in FIG. 6, the front plate 52 and the blade 54 are integrally formed.

In this embodiment, injection molding is employed for forming the front plate 52 and the blade 54 integrally.
As in the case of resin injection molding, a light metal raw material in the form of a pellet is kneaded and melted directly in an injection molding machine without using a melting furnace or the like, and is injected into a mold to obtain a molded product.

As described above, the front plate 52 and the blade 54 can be integrally formed. In this embodiment, since the front plate 52 and the blade 54 are integrally formed, there is no crimping projection for fixing the front plate 52 on the upper surface of the front plate 52. Can reduce the air resistance at the upper surface of the device. In addition, since there is no gap between the front plate 52 and the blades 54 because they are integrally formed, the airtightness between the flow paths formed between the blades 54 is increased, and the aerodynamic performance can be increased.

Next, FIGS. 7 and 8 show an injection molding structure in this embodiment.

In the present embodiment, after forming, the inner and outer diameters of the front plate 52 are subjected to concentric processing by press punching, mechanical cutting, or the like.
2 is improved in concentric accuracy by correcting run-out, bending, etc. occurring in the inner and outer diameter portions. As a result, the amount of unbalance of the impeller 35 caused by the molding is reduced, and the balance accuracy is improved.

Electric blower 1 particularly used for vacuum cleaner
When rotating at a high speed as described above, not only is the effect of reducing vibration noise large, but also the dimensional accuracy of the inner and outer peripheries of the impeller 35 is improved, and the fan casing 37 and the fixed guide vanes 34
Are stable, and the aerodynamic performance does not vary.

In this embodiment, on the inner peripheral side of the suction port 51,
A thin film gate 79 is formed from the gate 77 once so that the hot water flows uniformly to the front plate 52 on the circumference. Further, two basins 78 for preventing insufficient filling are provided on the outer peripheral side. These are necessary for stabilizing the quality at the time of injection molding, but they are unnecessary as a product after molding and need to be removed. In FIG. 8, the inner and outer peripheries of the arrows are respectively removed. In the present embodiment, by providing the sprue 77 and the basin 78 for preventing insufficient filling at the inner and outer peripheral portions of the front plate 52, it is possible to remove the inner and outer diameters at the same time as the post-processing, thereby increasing the number of working steps. Nothing.

As another embodiment of the present invention, FIG. 9 is a perspective view in which a rear plate 53 and a blade 54 are integrally formed. In this case, the structure as shown in FIGS. 10 and 11, as well as the effect of improving the balance accuracy and the aerodynamic performance as described above, can be obtained. That is, in FIG.
Thus, the inner peripheral portion of the rear plate 53 having the weakest rigidity can be made thicker to increase the rigidity. This is particularly advantageous for high-speed rotating machines. In the figure, the portion of the impeller 35 facing the air flow path on the side of the suction port 51 is raised to improve the flow at the inlet and improve aerodynamic performance. Further, in FIG. 11, the protrusion is extended in the direction opposite to the rotation shaft 26 to form a mounting portion to the rotation shaft 26, so that a separate boss conventionally used for mounting can be reduced.

In FIGS. 12 and 13, the thickness of the blade 54 is changed to a shape generally called an airfoil. FIG.
In the second example, an example in which a claw for fixing to the front plate 52 is provided,
FIG. 13 shows an example in which the thick portion of the blade 54 is robbed to make the thickness uniform and improve the formability.

In either case, the blade 54 and one of the plates can be integrally formed, and the degree of freedom in design is increased and the flow in the impeller 35 can be optimized as compared with the case of a thin plate as in the above-described conventional example. Aerodynamic performance can be improved.

In this embodiment, the integrally formed front plate 52 and blade 54 are formed of a magnesium alloy. This magnesium alloy is manufactured by US ASTM
The standard was AZ91D. This AZ91D alloy is an alloy containing 8.3 to 9.7% by weight of aluminum, 0.35 to 1.0% by weight of zinc, and 0.15 to 0.50% by weight of manganese, and has good formability. It is a high-purity product with reduced content of copper, nickel and iron.

In the present embodiment, the integral part of the front plate 52 and the blade 54 is made of AZ91D magnesium alloy, but aluminum 5.5-6.5% by weight, zinc 0.22% by weight, manganese 0.24-0. US A containing 1.6% by weight
S60 AM60B magnesium alloy may be used.

The specific gravity (g / cm 3) of the magnesium alloy is about 1.8, and the specific gravity of the aluminum alloy is 2.7.
The weight can be reduced by about 2/3.

In this embodiment, the rear plate 102 is made of A5052 aluminum alloy of JIS standard.
IS-standard Al-Mn alloy (3000 series), Al-S
i-based alloy (4000 series), Al-Cu-Mg based alloy (2
000), Al-Mg-Si alloy (6000),
Any of Al-Zn-Mg alloys (7000 series) may be used.

FIG. 14 shows an example of the vacuum cleaner.

A dust collecting chamber 82 and an electric blower 1 are provided inside the cleaner body 81, and a hose 83 is connected to the cleaner body 81.
It is connected to the. At the connection between the hose 83 and the extension pipe 84, a hand operation unit 85 for setting the suction force or the like of the electric blower 1 is provided. The main body control unit 86 is set to have the suction force set here. Control with. A suction port 87 is connected to the distal end of the extension tube 84.

[0045]

As described above, according to the present invention, the impeller is integrally formed to eliminate the caulking projection, so that air resistance, noise, and the like due to the caulking projection are reduced. Can be reduced.

Further, in the present invention, the front plate 52
By performing concentric processing on the inner and outer diameters of the inner and outer diameters by press cutting, mechanical cutting, or the like, run-out, bending, and the like generated in the inner and outer diameter portions due to molding distortion are corrected, and concentric accuracy is improved.
As a result, the amount of unbalance of the impeller 35 caused by molding is reduced, and the balance accuracy is improved. In particular, when rotating at a high speed like the electric blower 1 used in the vacuum cleaner, the effect of reducing the vibration noise is great, but not only this, but also the dimensional accuracy of the inner and outer circumferences of the impeller 35 is improved, and the fan casing is improved. The combination dimensions with the fixed guide blades 37 and the fixed guide vanes 34 are stabilized, and the aerodynamic performance is not varied. In addition, by providing a molding gate portion necessary for molding and a basin portion for preventing insufficient filling at the inner and outer peripheral portions of the front plate 52, it is possible to simultaneously remove the inner and outer diameters at the time of post-processing described above. There is no increase.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of an electric blower showing one embodiment of the present invention.

FIG. 2 is an exploded perspective view of a conventional impeller.

FIG. 3 is an external perspective view of an impeller according to one embodiment of the present invention.

FIG. 4 is a plan view of an impeller according to one embodiment of the present invention.

FIG. 5 is a sectional view of an impeller according to one embodiment of the present invention.

FIG. 6 is an exploded perspective view of an impeller according to one embodiment of the present invention.

FIG. 7 is a structural diagram of an impeller at the time of molding according to an embodiment of the present invention.

FIG. 8 is a structural view of an impeller at the time of molding according to an embodiment of the present invention.

FIG. 9 is an exploded perspective view of an impeller according to another embodiment of the present invention.

FIG. 10 is a sectional view of an impeller according to another embodiment of the present invention.

FIG. 11 is a sectional view of an impeller according to another embodiment of the present invention.

FIG. 12 is an exploded perspective view of an impeller according to another embodiment of the present invention.

FIG. 13 is an exploded perspective view of an impeller according to another embodiment of the present invention.

FIG. 14 is a configuration explanatory view showing an example of a vacuum cleaner.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electric blower, 21 ... Housing, 22 ... Stator, 2
6 ... rotating shaft, 23 ... rotor, 35 ... impeller, 36 ... nut, 34 ... fixed guide blade, 37 ... fan casing, 3
2 ... End bracket, 52 ... Front plate, 53 ... Rear plate, 54 ... Blade, 77 ... Gate, 78 ... Puddle, 81 ... Vacuum cleaner body, 82 ... Dust collection chamber, 86 ... Main body control unit.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Fumio Joraku 1-1-1, Higashitaga-cho, Hitachi City, Ibaraki Prefecture Inside the Taga Headquarters, Electric Appliances Division, Hitachi, Ltd. 502 Machi-cho, Hitachi, Ltd. Machinery Research Laboratories (72) Inventor Takeshi Takeshi 7-1-1, Omika-cho, Hitachi City, Ibaraki Pref. Hitachi, Ltd. Hitachi Research Laboratory F-term (reference) BB06 CC02 DD05 DD12 DD17 DD25 DD26 EE01 EE10 EE13 EE19

Claims (6)

[Claims] 1. An electric motor housed in a housing, an impeller fixedly mounted on a rotating shaft of the electric motor, a fixed guide impeller disposed downstream of a flow path of the impeller, and the impeller and In the electric blower having a fan casing that covers the fixed guide blade, the impeller has a front plate having a suction port, and a rear plate that is disposed to face the front plate and has a mounting portion to the rotating shaft. Having a plurality of blades disposed between the front plate and the rear plate,
An electric blower, wherein at least one of the front plate or the rear plate and the blade are integrally formed, and an inner or outer peripheral surface of the integrally formed plate is processed. 2. An electric motor housed in a housing, an impeller fixedly mounted on a rotating shaft of the electric motor, a fixed guide impeller disposed on a downstream side of a flow path of the impeller, and the impeller and In the electric blower having a fan casing that covers the fixed guide blade, the impeller has a front plate having a suction port, and a rear plate that is disposed to face the front plate and has a mounting portion to the rotating shaft. Having a plurality of blades disposed between the front plate and the rear plate,
At least one of the front plate or the rear plate and the blade are integrally formed by injection molding or die casting, and the inner or outer peripheral surface of the plate is additionally processed by press working or machining. Characterized electric blower. 3. The electric blower according to claim 1, wherein the inner and outer diameters of the front plate or the rear plate formed integrally with the blade are concentrically processed. 4. The electric blower according to claim 2, wherein at least one of the front plate and the rear plate and the blade are integrally formed of a magnesium alloy or an aluminum alloy. 5. The electric blower according to claim 2, wherein a gate or a pool for forming is provided on the inner or outer peripheral surface of the front plate or the rear plate formed integrally. . 6. An electric vacuum cleaner comprising the electric blower according to claim 1. Description: