JPH08296593A - Electric blower - Google Patents

Abstract

PURPOSE: To provide an electric blower that can heighten air blasting efficiency without increasing the number of part items and the number of assembling steps. CONSTITUTION: A casing 4 for covering the front side of an impeller 2 fixed to the rotary shaft 5 of a motor 1, and the front side and outer periphery of a diffuser 3 covering the outer periphery of the impeller 2 is provided with a metal plate body 14 with a large number of holes 17 piercingly provided at the peripheral part of a suction port 15 opened to the front face, and a synthetic resin mold body 18 brought close to the inner peripheral surface of the inlet 7 of the impeller or the inlet peripheral part of the front face while closing the holes 17 and covering the port edge 16 of the suction port 15 of the body 14 and the peripheral part from both inner and outer faces.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric blower, and more particularly to an electric blower capable of improving the blowing efficiency without increasing the number of parts and the number of assembling steps.

[0002]

2. Description of the Related Art An electric blower used, for example, in an electric vacuum cleaner has a motor 101 as shown in the half sectional view of FIG.
And an impeller 102 driven by this motor 101
And the diffuser 103 arranged around the outer periphery of the impeller 102, the impeller 102 and the diffuser 1
03 and a casing 104 that covers the outer periphery of the diffuser 103.

The impeller 102 is disposed on a rear shroud 106 fixed to a rotary shaft 105 protruding from the front surface of the motor 101 and a front side of the shroud 106 with a predetermined distance.
It has a front shroud 108 having a circular inlet 107 formed in the center, and a plurality of blades 109 arranged between the front and rear shrouds 108 and 106.

Further, the casing 104 has a suction port 110 which covers the front surface and the outer periphery of the impeller 102 and has a circular opening at the center of the front surface, and its rear end is fixed to the frame 111 of the motor 101.

The casing 104 is made of, for example, an electrogalvanized steel plate, and the rim 112 of the suction port 110 is extended to the rear side to narrow the gap between the casing 104 and the front shroud 108. I am trying.

Reinforced washers 113 and 114 are fixed to the front and rear surfaces of the central portion of the rear shroud 106 by rivets 115, and a bush 116 fitted to the rotary shaft 105 is welded to the rear washer 114. To be done. These rear shroud 106, both washers 113,
114 and the bush 116 are externally fitted to the front end of the rotary shaft 105, and the nut 117 screwed to the front end of the rotary shaft 105 is tightened, whereby the impeller 102 is rotated.
Fixed to.

A portion 118 of the casing 104 on the front side of the diffuser 103 is horizontally formed so as to be in close contact with the front surface of the diffuser 103.

[0008]

When the casing 104 is made of metal, there is a problem in that the impeller 102 comes into contact with each other due to factors such as press accuracy and vibration, and abnormal noise is generated.
In order to solve this problem, it is necessary to increase the clearance between the casing 104 and the impeller 102 so that the impeller 102 does not contact with each other. in this case,
A vortex is generated due to the gap between the casing 104 and the impeller 102, and the ventilation efficiency is reduced. The problems will be specifically pointed out below.

That is, in the conventional electric blower shown in FIG. 1, due to the relationship between the machining dimensional accuracy of the parts and the dimensional accuracy of the assembly, between the inner peripheral edge of the front shroud 108 and the edge 112 of the suction port 110 of the casing 104. There is a problem that a gap is created and air leaks from the gap between the vicinity of the inlet of the impeller 102 and the casing 104 to the front side of the impeller 102 to lower the blowing efficiency.

In the electric blower described in Japanese Unexamined Patent Publication No. 5-133391, the provision of the seal member narrows the gap between the inlet side of the impeller 102 and the casing 104, thereby preventing a decrease in blowing efficiency. However, in this case, since the number of parts increases, the number of assembling steps and the time increase, which causes a problem of high cost.
Further, it becomes very difficult to attach the seal member, and the holding force of the seal member is weak, which may cause the seal member to come off during rotation of the impeller.

The first electric blower of the present invention has been made in consideration of the above circumstances, and the flow of air leaking from the inlet side of the impeller to the front side thereof without increasing the number of parts and the number of assembling steps. It is an object of the present invention to provide an electric blower capable of reducing the air flow and improving the air blowing efficiency.

Further, in the conventional electric blower shown in FIG. 1, air leaks from between the outer periphery of the impeller 102 and the casing 104 to the front side of the impeller 102, and this air enters the inlet 110 along the rear surface of the casing 104. However, there is a problem that the air flow efficiency decreases due to the air leakage.

Therefore, in the first electric blower of the present invention, further considering this situation, the flow of air leaking from the outer periphery of the impeller to the front side thereof is reduced without increasing the number of parts and the number of assembly steps. It is an object of the present invention to provide an electric blower capable of increasing the blowing efficiency.

Further, in the conventional electric blower, for example, as shown in the sectional view of FIG. 2 or the sectional view of FIG. 3, the front portion of the diffuser 103 of the casing 104 is brought into close contact with the front surface of the diffuser 103 due to a processing error. Instead, a space that expands outward is formed on the upper side of the diffuser 103, and a vortex or turbulent flow occurs in this space (FIG. 2), or a space that expands inward is formed on the upper side of the diffuser 103. The air flowing in from the front side of the impeller 102 via the
There is also a problem that the airflow sent through the inside of the diffuser 103 to the diffuser 103 is disturbed (FIG. 3), and the blowing efficiency is reduced.

The second electric blower of the present invention has been made in consideration of the above circumstances, and blows air by bringing the casing 104 into close contact with the upper surface of the diffuser 103 without increasing the number of parts and the number of assembly steps. It is an object of the present invention to provide an electric blower capable of improving efficiency.

[0016]

A first electric blower of the present invention is a motor, an impeller fixed to a rotating shaft projecting from the front surface of the motor and having an inlet opening at the center of the front surface, and a front surface of the impeller. In order to achieve the above-mentioned object, an electric blower including the casing that has a suction opening that covers the outer periphery and has a circular opening in the center of the front surface is provided with the following means.

That is, the first electric blower of the present invention is
The casing is a metal plate body having a large number of holes penetrating the periphery of the suction port, and the holes are filled with the casing and covers both the front and rear surfaces and the inner peripheral surface of the suction port surrounding portion, the impeller An electric blower, comprising: a synthetic resin molded body that approaches an inlet inner peripheral surface or a front peripheral portion of the inlet.

The first electric blower of the present invention further comprises:
In order to reduce the flow of air that leaks from the outer periphery of the impeller to the front side of the impeller and to improve the blowing efficiency, the synthetic resin molded body is integrally molded with the rear surface of the impeller, and there is a continuous air passage rib protruding toward the impeller. Will be issued.

Further, the second electric blower of the present invention is provided with a motor, an impeller fixed to a rotating shaft projecting to the front surface of the motor, having an inlet opening at the center of the front surface, and arranged around the outer periphery of the impeller. In order to achieve the above object, an electric blower comprising a diffuser, a front surface of the impeller and the diffuser, and a casing having a suction port at the center of the front surface, which covers the outer periphery of the diffuser,
The following measures are taken.

That is, in the second electric blower of the present invention, the casing has a large number of holes penetrating the front portion of the diffuser side by side in the circumferential direction, and at least the front and rear portions of the front portion of the diffuser are filled with these holes. An electric blower comprising: a synthetic resin molded body covering both surfaces.

[0021]

In the first electric blower of the present invention, the casing is made of a metal plate having a large number of holes penetrating the periphery of the suction port, and the holes are filled and the periphery of the suction port of the main body is filled. Since a synthetic resin molded body that covers both the front and rear surfaces and the inner peripheral surface of the portion and approaches the inlet inner peripheral surface of the impeller or the inlet peripheral portion of the front surface is provided, the synthetic resin molded body is inseparably integrated with the main body of the casing. Therefore, the number of parts and the number of assembling steps do not increase.

Further, since the synthetic resin molded body covers both the front and rear surfaces and the inner peripheral surface of the peripheral portion of the suction port of the main body, the shape and size of the suction port can be formed with higher accuracy than in the case of molding a metal plate. Therefore, it is possible to reduce the gap formed between the suction port of the casing or the vicinity of the suction port and the inlet of the impeller or the front surface in the vicinity thereof.

Further, even if the casing and the impeller interfere with each other due to a component dimensional error or an assembly dimensional error during assembly, the synthetic resin molded body is ground by the impeller while the impeller is rotated several times, and the interference is short. This can be resolved within the time, and the gap between the casing and the impeller on the suction port side or the inlet side can be minimized.

By thus reducing the gap between the suction port of the casing and the inlet side portion of the impeller, the flow rate of the airflow leaking from the gap between the suction port of the casing and the impeller to the front side of the impeller is reduced, Blower efficiency can be improved.

In the first electric blower of the present invention, in the case where the synthetic resin molded body is integrally molded with the rear surface of the molded body and the wind-cutting ribs projecting toward the impeller are continuously fed, the outside of the impeller is Since the wind-off rib blocks the flow of air leaking from the surroundings to the front side, the flow rate is reduced, and the ventilation efficiency is further enhanced.

Further, in the second electric blower of the present invention, the casing has a large number of holes penetrating the front part of the diffuser side by side in the circumferential direction, and the front and rear surfaces of the front part of the diffuser are filled with these holes. Since it is equipped with a synthetic resin molded body that covers the front part of the diffuser, the shape of the front part of the diffuser can be accurately formed in close contact with the front surface of the diffuser, and the airflow flowing into the diffuser leaks to the front side of the diffuser and forms a vortex or turbulence. It is possible to prevent the airflow from flowing from the front side of the impeller to the front side of the diffuser into the diffuser to form a vortex or turbulent flow, thereby improving the blowing efficiency.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The electric blower according to the first embodiment of the present invention will be described in detail with reference to FIGS. 4 to 7.

As shown in the half sectional view of FIG. 4, the electric blower according to the first embodiment of the present invention has a motor 1, an impeller 2 driven by the motor 1, and an outer periphery of the impeller 2. The diffuser 3 to be arranged is provided with a casing 4 that covers the impeller 2 and the front surfaces of the diffuser 3 and the outer periphery of the diffuser 3.

The impeller 2 is provided with a rear shroud 6 made of an electrogalvanized steel plate or the like fixed to a rotating shaft 5 protruding from the front surface of the motor 1, and a front side of the shroud 6 with a predetermined distance therebetween, and at the center thereof. It has a front shroud 8 made of an electrogalvanized steel plate or the like in which a circular inlet 7 is formed, and a plurality of blades 9 made of an electrogalvanized steel plate arranged between the front and rear shrouds 8 and 6.

Washers 10 and 11 are fixed to the front and rear surfaces of the central portion of the rear shroud 6, and a boss 12 which is fitted onto the rotary shaft 5 is welded to the rear washer 11 so that the rear shroud 6, The impeller 2 is fixed to the rotary shaft 5 by fitting the washers 10 and 11 and the boss 12 onto the front end of the rotary shaft 5 and tightening the nut 13 screwed onto the front end of the rotary shaft 5.

The casing 4 is provided with a body 14 formed by deep drawing of galvanized steel sheet or the like, and a suction port 15 arranged coaxially with the inlet 7 of the impeller 2 is formed in the center of the body 14. To be done. This suction port 15
The rim 16 of the is extended rearward so as to project into the inlet 7 for guiding air to the inlet 7.

As shown in the plan views of FIGS. 4 and 5, a large number of fan-shaped holes 17 lined up in the circumferential direction and the radial direction are penetratingly provided around the suction port 15 of the main body 14, and these holes are formed. 17
The casing 4 is provided with a synthetic resin molded body 18 that covers the front and rear sides of the front body 14 of the front shroud 8, the inner and outer peripheral surfaces of the rim 16 of the suction port 15, and the rear end surface.

As described above, by covering the suction port 15 and its peripheral portion with the synthetic resin molded body 18, the shape and dimensions of the suction port 15 are compared with those of the conventional example in which a metal plate is formed by plastic working. Since it can be formed with high precision, the distance between the suction port 15 and the inner peripheral surface or the front surface of the inlet 7 of the impeller 2 can be reduced. As a result, the suction port 15 of the casing 4 and the inlet 7 of the impeller 2
Or, it is possible to reduce the amount of air leaking to the front side of the impeller 2 from a gap between the airflow efficiency and the vicinity thereof, and to improve the blowing efficiency. Also, the synthetic resin molded body 18
Since the casing is not formed on the entire front surface of the casing 4, it is possible to avoid a decrease in heat radiation.

As shown in FIG. 4, in this embodiment, the synthetic resin molded body 18 covering the inner and outer peripheral surfaces and the rear end surface of the rim 16 of the suction port 15 is formed into an angular cross section. For example, as in the second embodiment of the present invention shown in the sectional view of FIG. 6, the rear edge portion of the synthetic resin molded body 18 is rounded from the inner peripheral side to the outer peripheral side so that the air flow sucked from the suction port 15 is You may make it guided to the inlet 7 of the impeller 2 more smoothly.

Further, as in the third embodiment of the present invention shown in the sectional view of FIG. 7, the impeller 2 is arranged concentrically with the portion of the synthetic resin molded body 18 which further covers the rim 16 of the suction port 15. The wind-blocking ribs 19 projecting toward the front surface of the
As in the fourth embodiment of the present invention shown in the cross-sectional view of FIG. 8, a synthetic resin molded body 18 that covers the rim 16 of the suction port 15.
It is also possible to mold the wind cutting rib 20 having a triangular cross section, which is arranged concentrically with the above portion and which gradually projects outwardly along the front surface of the impeller 2 integrally with the synthetic resin molded body 18.

The electric blower according to the fifth embodiment of the present invention has a motor 1, an impeller 2 driven by the motor 1, and an impeller 2 as shown in the half sectional view of FIG.
And the impeller 2 arranged around the outside of the
And a casing 4 that covers the front surface of the diffuser 3 and the outer periphery of the diffuser 3.

The casing 4 is provided with a main body 14 formed of an electrogalvanized steel plate or the like by plastic working such as deep drawing. As shown in plan views of FIGS. 9 and 10,
A large number of fan-shaped holes 21 arranged in two rows inside and outside in the circumferential direction are formed in a portion of the main body 14 on the front side of the diffuser 3. As shown in the sectional views of FIGS. 9 and 11, the casing 4 is provided with a synthetic resin molded body 22 that fills these holes 21 and covers both the front and rear surfaces of the front portion of the diffuser 3 of the main body 14. .

As described above, by covering the rear surface of the front portion of the diffuser 3 of the main body 14 with the synthetic resin molded body 22, the rear surface of the front portion of the diffuser 3 of the casing 4 is brought into close contact with the front surface of the diffuser 3 accurately. It can be formed in a horizontal plane. For example, as shown in FIG. 12, the front part of the diffuser 3 of the main body 14 protrudes outward, and as shown in FIG. 13, the front part of the diffuser 3 of the main body 14 is inside. And go forward, and diffuser 3
Even in the case where the space is formed on the front side of the diffuser 3, the space formed on the front side of the diffuser 3 can be filled with the synthetic resin molded body 22, and the rear surface of the front portion of the diffuser 3 of the casing 4 can be accurately formed. It can be formed on a horizontal surface that is in close contact with the front surface of No. 3. As a result, the airflow flowing into the diffuser 3 leaks to the front side of the diffuser 3 to form a vortex or turbulence, or the airflow flows from the front side of the impeller 2 to the diffuser 3 via the front side of the diffuser 3 to generate a vortex or turbulence. The formation is prevented and the blowing efficiency is improved.

In the above-described embodiment, the inner peripheral portion of the synthetic resin molded body 22 covering the rear surface of the casing 4 does not project rearward from the front surface of the diffuser 3, but the present invention shown in FIG. In the sixth embodiment, the inner peripheral portion 22 of the portion of the synthetic resin molded body 23 covering the rear surface of the casing 4 is projected rearward to the position of the rear surface of the outer peripheral portion of the front shroud 8 of the impeller 2. ,
The synthetic resin molded body 22 can more reliably prevent the airflow from flowing from the front side of the impeller 2 to the front side of the diffuser 3 into the diffuser 3.

The other constructions, functions and effects of this embodiment are the same as those of the above-mentioned fifth embodiment, and the detailed description thereof will be omitted to avoid duplication.

As shown in the plan view of FIG. 15, the main body 14 of the casing 4 of the seventh embodiment of the present invention has a large number of fan-shaped holes 17 which are dispersed and opened in the entire front portion 24 of the impeller 2. As shown in the sectional view of FIG. 16, the casing 4 fills the main body 4 and these holes 17 of the main body 4, and extends from the suction port 15 to the stepped portion 25 around the outer periphery of the portion 24. A synthetic resin molded body 18 covering both surfaces of 14 and a plurality of concentric wind-cutting ribs 26 protruding from the rear surface of the synthetic resin molded body 18 toward the impeller 2.

In this embodiment, the flow of air leaking from the outer periphery of the impeller 2 to the front side of the impeller 2 is blocked by the wind-off ribs 26, and the flow rate thereof is reduced.
As a result, a decrease in the air blowing efficiency due to air leakage from the outer periphery of the impeller 2 to the front side of the impeller 2 is reduced, and the air blowing efficiency is increased.

Since the other construction, operation and effect of this embodiment are the same as those of the above-mentioned first embodiment, their description will be omitted to avoid duplication.

The eighth embodiment of the present invention shown in the sectional view of FIG. 17 is one in which the wind cutting rib 26 of the preceding example is extended to the vicinity of the impeller 2, and in this case, the outer periphery of the impeller 2 is provided. From the front side of the impeller 2 is more reliably prevented from leaking from the impeller 2 to the front side of the impeller 2, and the flow of air flowing along the front surface of the impeller 2 from the inlet 7 side of the impeller 2 to the front side of the impeller 2 is prevented. Blocked by the labyrinth effect. Therefore, both the reduction of the ventilation efficiency due to the air leakage from the outer periphery of the impeller 2 to the front side of the impeller 2 and the reduction of the ventilation efficiency due to the air leakage from the inlet 7 side of the impeller 2 to the front side of the impeller 2 are largely prevented. As a result, it is possible to further improve the ventilation efficiency.

The other construction, operation and effect of this embodiment are the same as those of the previous example, and therefore their explanation is omitted to avoid duplication.

[0046]

As described above, according to the first electric blower of the present invention, the synthetic resin molded body added to the casing is inseparably integrated with the main body made of the metal plate of the casing. The number of points and the number of assembling steps do not increase, and the number of assembling steps can be reduced and the cost can be reduced as compared with the conventional example in which the seal member is provided between the front shroud and the casing.

Further, since the rim and the peripheral portion of the suction port of the main body made of the metal plate of the casing are covered with the synthetic resin mold member from both inner and outer surfaces, the shape and size of the suction port can be formed with high accuracy, and the casing The ventilation efficiency can be improved by reducing the gap between the suction port and the front shroud.

Further, even if the casing and the front shroud interfere with each other due to a component size error or an assembly size error during assembly, the synthetic resin molded body is ground by the impeller while the impeller is rotated several times, and the interference is short. It can be eliminated within the time, and the gap between the casing and the impeller can be minimized to further improve the blowing efficiency.

In the first electric blower of the present invention, when a synthetic resin molded body is integrally molded with the rear surface of the molded body and a wind-cutting rib projecting toward the impeller is continuously provided, the outer side of the impeller is removed. It is possible to reduce the air flow that leaks from the surroundings to the front side of the impeller and that flows along the rear surface of the casing, which reduces the reduction in air blowing efficiency due to air leakage from the outer periphery of the impeller to the front side of the impeller. Blower efficiency can be improved. Further, in this case, if the wind-blocking rib is extended to the vicinity of the impeller, the flow of air leaking from the inlet side of the impeller to the front side of the impeller can be further blocked by the labyrinth effect generated between the wind-blocking rib and the impeller. Therefore, it is possible to reduce the decrease in the air blowing efficiency due to the leakage of air from the inlet side of the impeller to the front side of the impeller and improve the air blowing efficiency.

In the second electric blower of the present invention, since the synthetic resin molded body added to the casing is inseparably integrated with the metal body of the casing, the number of parts and the number of assembling steps do not increase. As compared with the conventional example in which the seal member is provided between the front shroud and the casing, the number of assembling steps can be reduced and the cost can be reduced.

Further, since the rear surface of the front portion of the diffuser of the casing is covered with the synthetic resin molded body,
The rear surface of this part can be formed into a shape that closely adheres to the front surface of the diffuser, and the airflow that flows into the diffuser leaks to the front side of the diffuser and forms a vortex or turbulence, or from the front side of the impeller to the diffuser via the front side of the diffuser. The airflow can be prevented from forming an eddy current or a turbulent flow to improve the blowing efficiency.

[Brief description of drawings]

FIG. 1 is a half sectional view of a conventional example.

FIG. 2 is a sectional view of a main part of a conventional example.

FIG. 3 is a sectional view of a main part of a conventional example.

FIG. 4 is a half sectional view of the first embodiment of the present invention.

FIG. 5 is a plan view of the main body of the casing according to the first embodiment of the present invention.

FIG. 6 is a sectional view of an essential part of a second embodiment of the present invention.

FIG. 7 is a sectional view of an essential part of a third embodiment of the present invention.

FIG. 8 is a sectional view of an essential part of a fourth embodiment of the present invention.

FIG. 9 is a half sectional view of a fifth embodiment of the present invention.

FIG. 10 is a plan view of a main body of a casing according to a fifth embodiment of the present invention.

FIG. 11 is a sectional view of an essential part of the fifth embodiment of the present invention.

FIG. 12 is a sectional view of an essential part of a fifth embodiment of the present invention.

FIG. 13 is a sectional view of an essential part of the fifth embodiment of the present invention.

FIG. 14 is a sectional view of an essential part of a sixth embodiment of the present invention.

FIG. 15 is a plan view of a main body of a casing according to a seventh embodiment of the present invention.

FIG. 16 is a sectional view of an essential part of a seventh embodiment of the present invention.

FIG. 17 is a sectional view of an essential part of the eighth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Motor 2 Impeller 4 Casing 5 Rotating shaft 7 Inlet 14 Main body 15 Suction port 16 Mouth edge 17 Hole 18 Synthetic resin molded body 21 Hole 22 Synthetic resin molded body

Claims (3)

[Claims] 1. A motor, an impeller fixed to a rotating shaft projecting from the front surface of the motor, and having an inlet opening at the center of the front surface, and a circular opening at the central portion of the front surface covering the front surface and the outer periphery of the impeller. In an electric blower including a casing having a suction port, the casing is made of a metal plate having a large number of holes penetrating the periphery of the suction port, and the suction port of the main body is filled with these holes. An electric blower, comprising: a synthetic resin molded body that covers a rim and a peripheral portion from both inner and outer surfaces and that approaches an inlet inner peripheral surface or a front inlet peripheral portion of the impeller. 2. The electric blower according to claim 1, wherein the synthetic resin molded body is integrally molded with a rear surface of the molded body, and wind-off ribs protruding toward the impeller are continuously provided. 3. A motor, an impeller fixed to a rotating shaft protruding from the front surface of the motor, having an inlet opening at the center of the front surface, a diffuser arranged around the outer periphery of the impeller, and front surfaces of the impeller and the diffuser. And an electric blower that covers the outer periphery of the diffuser and has a casing having a suction port in the center of the front surface, wherein the casing has a large number of holes penetrating side by side in the circumferential direction at the front side of the diffuser, and these holes. An electric blower comprising: a synthetic resin molded body that is filled with and covers at least both front and rear surfaces of a front portion of the diffuser.