KR100231145B1 - Electric blower - Google Patents

Abstract

While forming a volute wall 19 on the fan 22 side of the diffuser 14 against the outer circumference of the fan 22, the wind from the fan 22 on the outer circumference of the diffuser 14. Guide blades (17) for guiding the back surface of the diffuser (14), and forming a flat portion (20) between the volute wall (19) and the guide blades (17) and at the same time the volute wall (19). The number of the electric blower with the number of guide wings (17) different.

Since the flat portion is formed between the volute wall 19 and the guide vane 17, the air divided by the volute wall 19 joins while turning to the outer circumferential side of the diffuser 14 to guide the vane 17 In addition, the wind from the fan 22 is reduced by the fact that the noise can be reduced and the blowing efficiency can be improved and the number of the volute walls 19 and the guide vanes 17 are different. Since the frequency of the wind sound generated at the inlet of the guide blade 17 and the wind sound when contacting the) is different, it is possible to reduce the noise by preventing the amplification of the frequency.

Description

Electric blower

The present invention relates to an electric blower used in an electric vacuum cleaner and the like.

Diffusers of electric blowers are conventionally provided with external ribs and exhaust ribs formed on the back of the diffuser, as disclosed in Japanese Patent Laid-Open No. 3-78600 (F04D 29/44). Volumes formed on the main surface and formed on an inclined passage for guiding the wind from the fan to the diffuser back side, or the volume formed on the upper surface of the diffuser as disclosed in Japanese Patent Application Laid-Open No. 7-35097 (F04D 29/44). It is known to have an exhaust rib formed at the bottom of the bolute wall and the diffuser.

The former has a wide operating range of air volume because there is no volute wall on the upper surface of the diffuser, but the maximum efficiency is low and surging occurs easily, and the latter has a narrow volume of air volume due to a volute wall, but the maximum efficiency is low. It is characterized by high and difficult surging.

Therefore, as shown in Japanese Patent Application Laid-Open No. 60-247093 (F04D 25/08), a volute wall is formed on the upper surface of the diffuser, an exhaust passage is formed on the rear surface of the diffuser, and a fan is formed on the outer circumferential surface of the diffuser. The inclined passage which guides the wind from the diffuser to the back side is provided, and it has also served as the two types of characteristics mentioned above.

However, since the diffuser has the same number of volutes and the number of inclined passages, and also serves as a wall on the inner circumferential side of the inclined passage of the volute wall, the wind discharged from the fan is divided into the number of volute walls, and most of the diffusers are turning. It is unintentionally introduced into a continuous inclined passage to the outlet of the volute wall and exhausted to the outlet of the exhaust passage with the number divided by the volute wall.

Therefore, the wind noise generated when the wind discharged from the fan abuts the volute wall and the wind noise generated at the inlet of the inclined passage have the same frequency, thereby increasing the noise.

For this reason, it is possible to increase the frequency of noise when the wind from the fan hits the volute wall while reducing the number of volute walls and the number of oblique passages continuous to the volute wall, thereby reducing the discomfort caused by the noise. With this configuration, the angle of the inclined passage is increased, which causes the occurrence of surging and a decrease in efficiency.

The present invention has been made in view of the above drawbacks, and an object thereof is to provide an electric blower capable of reducing noise and improving efficiency.

1 is a perspective view of a diffuser used in an electric blower showing an embodiment of the present invention.

2 is a top view of the same.

3 is the same view.

4 is a cross-sectional view.

5 is a partially cutaway view of the electric blower.

* Explanation of symbols for main parts of the drawings

2: electric motor 3: blower

5: stator 6: rotor

14 diffuser 16: inclined surface

17: guide wing 18: exhaust passage

19: volute wall 20: flat part

22: fan

The present invention consists of an electric motor having a stator and a rotor and a blower having a fan and a diffuser, and is formed on the fan side of the diffuser so as to face the outer circumference of the fan and divides the wind from the fan. A wedge wall, a guide vane formed on the outer circumferential surface of the diffuser to guide the wind from the fan to the back of the diffuser, and an exhaust passage formed on the back of the diffuser, with a gap between the volute wall and the guide vane. Characterized in that formed.

In addition, the present invention is composed of an electric motor having a stator and a rotor, and a blower having a fan and a diffuser, and formed on the fan side of the diffuser so as to face the outer circumference of the fan and divide the wind from the fan. And a guide vane formed on the outer circumferential surface of the diffuser to guide the wind from the fan to the back of the diffuser, and an exhaust passage formed on the back of the diffuser to guide the number of volute walls. It is characterized by a different number of wings.

It is preferable to make the number of the volute walls described above into approximately multiples of the blade number of the fan, and more preferably to have a minority number close to approximately multiples of the number of blades.

In addition, the present invention is composed of an electric motor having a stator and a rotor, and a blower having a fan and a diffuser, and formed on the fan side of the diffuser so as to face the outer circumference of the fan and divide the wind from the fan. A volute wall formed on the outer circumferential surface of the diffuser to guide the wind from the fan to the back of the diffuser, and an exhaust passage formed on the back side of the diffuser. Characterized in that formed.

Moreover, it is preferable to make the inclined surface of a guide blade into the substantially triangular shape by which the area gradually expands toward the downstream from the upstream of the air flow from a fan.

In addition, the inclined surface of the guiding blade is formed into an approximately triangular shape gradually expanding the area from the upstream side to the downstream side of the air flow from the fan, and from the inner diameter portion of the volute wall to the outer diameter portion of the diffuser on the fan side of the diffuser. It is preferable to incline downward gradually.

EXAMPLE

EMBODIMENT OF THE INVENTION Next, embodiment of this invention is described in detail based on drawing.

1 is an electric blower and is comprised by the electric motor 2 and the blower 3. As shown in FIG.

First, referring to the electric motor 2, the stator 5 and the rotor 6 are housed in a conventional bracket having a bottom with one end open, and one end opening of the bracket 4 It is covered with a terminal plate 7.

8 is a brush holding part fixed to the bracket 4 described above, and the carbon brush 9 held therein is elastically contacted with the outer circumferential surface of the commutator 10 of the rotor 6.

11 is a ball bearing press-fixed and fixed to the bottom of the bracket 4 and the center of the terminal plate 7, respectively, and the rotation of the both ends of the rotating shaft 12 of the rotor 6 is freely axially supported.

13 is a sleeve which is disposed between the ball bearing 11 of the rotating shaft 12 and the fan 22 to be described later and serves as a gap maintaining means for maintaining a gap between the fan 22 and the ball bearing 11. .

Next, a blower is demonstrated.

14 is a diffuser fixed to the terminal plate 7 with a screw 15 from the fan 22 side (surface side of the diffuser 14) to be described later on the outer circumference of the diffuser 14 to the electric motor 2 side. (Guide wings 17 having an inclined surface 16 inclined toward the back side of the diffuser 14 are formed (8 in the present embodiment) over the entire circumference and the inclined surface 16 of the guide wings 17). Is formed in a substantially triangular shape in which the area gradually expands from the upstream side to the downstream side from the upstream side (fan 22 side described later) of the air flow.

18 is an exhaust passage formed on the back surface of the diffuser 14, and the guide blade 17 and the same number are formed continuously to the guide blade 17. As shown in FIG.

19 is a volute wall arranged in a ring shape with a flat portion 20 between the guide vanes 17 on the surface of the diffuser 14, and the fan 22 described later in the space surrounded by the volute wall 19. The air from the fan 22 is divided and rectified by the plurality of volute chambers 21 formed by the volute wall 19 at the same time.

In the present embodiment, 17 volute walls 19 are formed. The inner diameter of the volute wall 19 arranged in a ring is 97 mm, and the outer diameter of the volute wall is 111 mm.

The surface of the diffuser 14 is inclined downwardly (0.9 mm in this embodiment) from the inner diameter of the volute wall 19 toward the outer circumferential portion, and the upper surface A of the inlet portion of the guide vane 17. Since the upper surface B of the inner diameter portion of the outlet portion is higher than the position B (about 0.4 mm in the present embodiment), the air flow discharged from the fan 22 described later easily flows in the inclination of the guide blade 17. Backflow of air from the vicinity of the exit of the guide vane 17 to the surface side of the diffuser 14 can be prevented.

22 is a fan fixed to the rotating shaft 12 of the rotor 6 extending through the diffuser 14, the front of the shroud 24 having an inlet 23 in the center of the fan 22, the rear Shroud (

25 and a plurality of wings 26 (8 sheets in the present embodiment) that are fixed between the front and rear protective plates 24 and 25 described above.

27 is a fan cover which covers the diffuser 14 and the fan 22, and is press-fitted and fixed to the terminal plate 7, and the inlet port 28 is formed in the substantially center part of the fan cover 27. As shown in FIG.

In this way, the air flow discharged from the fan 22 is divided by the number of the volute wall 19, rectified in the volute chamber 21 and forcibly introduced into the guide vane 17, but the volute wall 19 and the guide vane are Since the flat portion is formed between the 17, the air flow divided by the volute wall 19 smoothly joins while turning to the outer circumferential side of the diffuser 14 and is introduced into the inclined surface 16 of the guide vane 17. It can reduce noise and improve the blowing efficiency.

In addition, since the number of the volute wall 19 and the guide vanes 17 are different, the wind noise and the guide vane 17 generated when the wind discharged from the fan 22 to be described later abuts the volute wall 19. Since the frequency of wind noise generated at the entrance is different, noise can be reduced.

In the present embodiment, the number of volute walls 19 is set to 17 and the number of wings of the fan 22 is eight. In this case, if the volute wall 19 is formed 16 times as large as the wing, the wind noise is generated at the same time between the fan 22 and the volute wall 19 at the same time as the fan 22 rotates. There is a problem that increases, and it is preferable that the number of the volute walls 19 be before and after the drainage of the number of wings of the fan 22.

In addition, when the number of the volute wall 19 is set to a small number close to the multiple of the number of wings, wind noise occurs at two or more places between the fan 22 and the volute wall 19 during the rotation of the fan 22. It is most preferable that the number of volute walls 19 should be a few, close to the multiple of the number of blades.

In addition, the number of the volute walls 19 is 17 as the number of the volute walls 19, the number of wings of the fan 22 is eight, and the number of the guide vanes 17 is eight. By roughly draining the number of blades, the flow rate of the wind discharged by the fan 22 is the fastest and is efficiently rectified at the outlet of the fan 22 where surging is likely to occur. As a result of the experiment, the guide blade 17 is approximately equal to the number of blades of the fan 22 (six to eleven), so the conversion efficiency from the dynamic pressure to the static pressure is the best, and the blowing efficiency is prevented from being lowered. Can be reduced.

In addition, since the upper surface of the guide blade 17 has a substantially triangular shape, the air passage area gradually expands from the guide blade 17 toward the exhaust passage 18, thereby improving the conversion efficiency from dynamic pressure to constant pressure, thereby improving surging. It can prevent the occurrence and improve the blowing efficiency.

In addition, since the surface of the diffuser 14 is gradually inclined downward from the inner diameter of the volute wall 19 toward the outer circumference, the upper surface of the outlet portion becomes higher than the upper surface of the inlet portion of the guide vane 17, so that the fan 22 The discharged air flow easily flows to the inclined surface 16 of the guide blade 17 and at the same time, it is possible to prevent backflow of air from the outlet of the guide blade 17 to the surface side of the diffuser 14.

In the above embodiment, the volume of the circle enclosed by the volute wall 19 is 97 mm, the outer diameter of the volute is 111 mm, and the maximum outer diameter of the diffuser is formed at 138.3 mm. When the diameter of the circle enclosed by (19) is A, the maximum outer diameter of the diffuser is A x 1.35 to A x 1.45, and the maximum outer diameter of the volute wall 19 is A x 1.13 to A x 1.24.

If the volute chamber 21 is too long, it is easy to become a resistance when the air volume changes, so that the performance decreases and the outer diameter of the fan cover 27 increases. However, as a result of the experiment, turbulence is generated by setting the above values. It is possible to prevent performance deterioration caused by the motor and to increase the size of the motor.

According to claim 1 of the present invention, since a gap is formed between the volute wall and the guide vane, the air flow divided by the volute wall joins smoothly while turning to the diffuser outer circumference to introduce the guide vane and reduce noise. In addition, the efficiency can be improved.

According to claim 2 of the present invention, since the number of guided vanes differs from the volume of the volute wall, wind noise generated when the wind discharged from the fan contacts the volute wall and the frequency of the wind noise generated at the inlet of the guide vane are different. The noise can be reduced by suppressing the amplification.

According to claim 3 of the present invention, the blowing efficiency can be improved by making the number of volumes of the volute wall approximately the multiple of the number of blades of the fan.

According to claim 4 of the present invention, when the number of volute walls is a small number of pieces close to the number of wings, wind noise does not occur at two or more places between the fan and the volute wall during the fan rotation, so that the noise is surely eliminated. Can be reduced.

According to claim 5 of the present invention, because the volute wall and the guide vane are discontinuously formed, the air flow divided by the volute wall is smoothly joined while turning to the outer circumferential side of the diffuser, and thus the noise is reduced. At the same time, efficiency can be improved, and since the frequency of the wind noise generated when the wind discharged from the fan contacts the volute wall and the wind noise generated at the guide wing opening are different, the noise amplification is suppressed to reduce the noise. Can be reduced.

According to claim 6 of the present invention, the air passage area gradually expands from the guide vanes to the exhaust passage to improve the conversion efficiency from the dynamic pressure to the static pressure, thereby preventing the occurrence of surging to improve the blowing efficiency.

According to the seventh aspect of the present invention, the air passage area gradually expands from the guide vanes to the exhaust passage to improve the conversion efficiency from the dynamic pressure to the static pressure, thereby preventing the occurrence of surging to improve the blowing efficiency.

In addition, the upper surface of the outlet portion is higher than the upper surface of the inlet portion of the guide blade, and the air flow discharged from the fan easily flows in the inclination of the guide blade, and at the same time, the reverse flow of air from the outlet of the guide blade to the surface side of the diffuser can be prevented.

Claims (7)

An electric motor 2 incorporating the stator 5 and the rotor 6 and a blower 3 incorporating the fan 22 and the diffuser 14, and the fan 22 of the diffuser 14. Formed on the outer circumferential surface of the diffuser 14 and the plurality of volute walls 19 which are formed opposite the outer circumference of the fan 22 and divide the wind from the fan 22 to diffuse the wind from the fan 22. (14) and a guide blade (17) for guiding to the back of the diffuser 14, and the exhaust passage (18) formed on the back of the diffuser (14), the spacing between the volute wall 19 and the guide blade (17) Electric blower, characterized in that formed. An electric motor 2 incorporating the stator 5 and the rotor 6 and a blower 3 incorporating the fan 22 and the diffuser 14, and the fan 22 of the diffuser 14. A plurality of volute walls 19 formed on the side facing the outer circumference of the fan 22 and dividing the wind from the fan 22 and on the outer circumferential surface of the diffuser 14 so as to form a fan 22. A guide blade 17 for guiding wind from the diffuser 14 to the rear surface of the diffuser 14 and an exhaust passage 18 formed on the rear surface of the diffuser 14 to guide the number of volumes of the volute wall 19. Electric blower, characterized in that different from the number of wings (17). 3. The electric blower according to claim 2, wherein the number of volute walls (19) is approximately a multiple of the number of blades of the fan (22). 3. The electric blower according to claim 2, wherein the number of volumes of the volute walls (19) is a minority number which is approximately a multiple of the number of blades of the fan (22). An electric motor 2 incorporating the stator 5 and the rotor 6 and a blower 3 incorporating the fan 22 and the diffuser 14, and the fan 22 of the diffuser 14. A plurality of volute walls 19 formed on the side facing the outer circumference of the fan 22 and dividing the wind from the fan 22 and on the outer circumferential surface of the diffuser 14 so as to form a fan 22. A guide wing 17 for guiding wind from the diffuser 14 to the rear surface of the diffuser 14 and an exhaust passage 18 formed on the rear surface of the diffuser 14; 17) and an electric blower characterized by being discontinuously formed. 6. An approximately triangular angle according to any one of claims 1 and 2, wherein the inclined surface 16 of the guide blade 17 gradually enlarges the area from the upstream side to the downstream side of the air flow from the fan 22. An electric blower characterized by the shape. 6. An approximately triangular angle according to any one of claims 1 and 2, wherein the inclined surface 16 of the guide blade 17 is gradually enlarged from the upstream side to the downstream side of the air flow from the fan 22. An electric blower characterized by being inclined and gradually inclined downward from the inner diameter of the volute wall (19) toward the outer diameter of the diffuser (14).

Images