TWI401366B - Electric blower and electric vacuum cleaner with the electric blower - Google Patents

Description

Electric blower and electric vacuum cleaner having the same

The present invention relates to an electric blower and an electric vacuum cleaner provided therewith.

In an electric blower for a conventional vacuum cleaner, a bracket for accommodating a bearing is attached to an opening side of an outer casing that is open at one end, and is disposed between a centrifugal fan and a bracket attached to a rotating shaft that protrudes from the bracket. The diffuser mounts the fan casing to the outer peripheral portion of the bracket by covering the diffuser and the fan.

A motor stator in which a commutator motor is fixed in the outer casing, and an exhaust port on the side of the outer casing on the opposite fan side. Further, a plurality of openings are provided in the bracket to which the fan casing is attached, and a part of the airflow from the centrifugal fan is discharged through the opening, and a cut-and-raised portion is formed along the outer surface of the outer casing. Thereby, the commutator motor is cooled by the air current flowing in the outer casing and the air current flowing outside (for example, refer to Patent Document 1).

Further, in a conventional electric blower, a bracket for accommodating a bearing is attached to an opening side of an outer casing that is open at one end, and a plurality of openings are provided in the bracket, and a total area of the opening is set as an exhaust on the opposite fan side. 70 to 80% of the total area of the opening, the edge portion on the outer peripheral side of the opening and the outer peripheral end portion of the return guide are almost identical, and the airflow from the centrifugal fan is discharged from both the opening and the exhaust port (for example, refer to Patent Document 2) ).

Further, in a conventional electric blower, a bracket for accommodating a bearing is attached to an opening side of an outer casing that is open at one end, and an opening is provided in the bracket, and an air flow discharged from the opening contacts the brush holder of the commutator motor ( For example, Patent Document 3 refers to).

[Patent Document 1] Japanese Patent Laid-Open No. Hei 3-105098

[Patent Document 2] Japanese Patent Laid-Open No. Hei 10-26099

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2005-201157

According to the prior art of the patent document, a part of the airflow discharged from the diffuser can be discharged without passing through the inside of the casing in which the commutator motor is housed, so that the loss can be reduced and the efficiency of the blower can be improved.

The airflow that flows in the outer casing in which the commutator motor is housed and flows out from the exhaust port on the counter centrifugal fan side is strong, but the brush that cools the commutator motor, which is particularly high in temperature, is strong, but Brush cooling is not considered in Patent Documents 1 and 2. This is because a plurality of openings are provided in the bracket, so that the amount of air used for cooling inside the motor is lowered, and since the opening is provided in the brush flow path, the cooling of the brush is insufficient, and the life of the motor may be shortened.

Further, in the technique of Patent Document 3, the airflow from the opening is brought into contact with the brush holder to indirectly cool the brush, but since the brush holder and the brush have an air layer, the cooling of the brush itself is insufficient. .

Further, since the noise generated from the centrifugal fan is directly discharged from the casing to the outside by providing the opening, there is a problem that the noise of the electric blower and the electric vacuum cleaner equipped therewith increases.

An object of the present invention is to solve the above problems as described above, to achieve a long life of the motor, and to improve the efficiency of the blower.

Further, an object of the present invention is to improve the life of the motor and the efficiency of the blower while reducing the noise generated from the centrifugal fan.

Further, it is an object of the present invention to provide an electric vacuum cleaner which improves the suction operation rate by using the electric blower.

In order to achieve the above object, an electric blower according to the present invention includes: a motor provided with a rotating member and a fixing member; and at least a pair of brush portions that slide with the rotating member, and an open end and the electric motor and the electric motor therein a housing that is housed in the brush portion, a rotating shaft that is provided on the rotating member, a centrifugal fan that is attached to the rotating shaft, and a diffuser that guides air discharged from the centrifugal fan to an air passage in the housing. a fan casing that is attached to the casing and has a suction port at a central portion thereof, and a protruding portion that protrudes toward the outer peripheral side is formed on the opening side of the casing, and the protrusion is formed on the opening side of the casing. The opening forms an opening through which the wind is discharged, and the opening is not provided in the air passage of the brush position in the air passage formed by the outer circumference of the fixing member and the inner diameter of the outer casing.

Further, in order to achieve the above object, an electric blower according to the present invention includes: a motor provided with a rotating member and a fixing member; and at least a pair of brush portions that slide with the rotating member, and an electric motor that is open at one end and internally a casing housed in the brush portion, a rotating shaft provided on the rotating member, a centrifugal fan attached to the rotating shaft, and a diffusion of an air passage that guides the air discharged from the centrifugal fan into the casing And a fan casing that is attached to the casing and has a suction port at a central portion thereof, and the diffuser is an annular body provided on the fan casing side, and a diffuser vane body having a plurality of vanes on the end bracket side and a return guide having the partition plate and the plurality of return vanes on the other side of the partition plate on which the plurality of vanes are disposed, in the diffuser A through hole is formed in the trailing edge side of the blade, and a protruding portion that protrudes toward the outer peripheral side is formed in the opening side of the outer casing, and an opening portion that discharges the wind is formed in the protruding portion. An opening portion, the opening portion is not provided in the position of the brush and the outer circumference of the duct inner diameter of the housing is formed by the fixing member in the air passage.

In order to achieve the above object, an electric vacuum cleaner according to the present invention includes a cleaner body that houses a dust collecting chamber and an electric blower, a pipe that has one end connected to the cleaner body, and a hand operation that is connected to one end of the pipe at one end. And an extension pipe having one end connected to the other end of the hand operation portion and a mouthpiece connected to the other end of the extension pipe, wherein the electric blower has an electric motor provided with a rotating member and a fixing member, And a brush portion that is slidable with the rotating member, a housing that is open at one end, and houses the motor and the all-electric brush portion inside, and a rotating shaft that is provided on the rotating member and is mounted on the rotating shaft a centrifugal fan and a diffuser that guides the air blown from the centrifugal fan to the air passage in the outer casing, and the centrifugal fan and the diffuser are attached to the outer casing and provided with suction at the center. The fan casing of the port, the diffuser is an annular body provided on the fan casing side and a diffuser blade body having a plurality of blades on the end bracket side And a return guide having the partition plate and the plurality of return guide vanes on the other side of the partition plate on which the plurality of blades are disposed, and a protruding portion that protrudes toward the outer peripheral side is formed in the opening side of the outer casing An opening that discharges the wind is formed in the protruding portion, and the opening is not provided in a predetermined range from the front side of the flow of the wind at the portion of the brush position.

According to the present invention, it is possible to efficiently cool the brush, thereby achieving a long life of the motor and improving reliability.

Moreover, according to the present invention, it is possible to improve the life of the motor and the efficiency of the blower while reducing the noise generated from the centrifugal fan.

Embodiments of the present invention will be described below with reference to the drawings.

[Example 1]

An electric vacuum cleaner according to an embodiment of the present invention will be described with reference to Figs. 1 and 2 .

Fig. 1 is a perspective view showing the appearance of an electric vacuum cleaner according to an embodiment of the present invention. Reference numeral 201 denotes a cleaner body that houses dust in a dust collecting chamber and an electric blower 308 (second drawing) for suction airflow required for dust collection, and 202 is a pipe whose one end is connected to the cleaner body 201, and 203 is A hand operating portion 204 having one end connected to the other end of the tube 202 is an extension tube having one end connected to the other end of the hand operating portion 203, and 205 is a mouthpiece body connected to the other end of the extension tube 204. 206 is a switch operation unit for performing cutting of the electric blower 308 provided in the hand operating unit 203.

In the above configuration, when the switch operation unit 206 of the hand operation unit 203 is operated, the electric blower 308 housed in the cleaner body 201 is operated to generate a suction airflow. Further, dust is sucked from the mouthpiece body 205, and dust is collected by the extension pipe 204, the hand operation portion 203, and the pipe 202 toward the dust collecting chamber of the cleaner body 201.

Next, the cleaner body 201 will be described using a longitudinal sectional side view of the cleaner body 201 in the electric vacuum cleaner shown in FIG.

The cleaner body 201 is formed by the lower case 301, the upper case 302, and the dust collecting cover 303. A suction port 304 is formed in the dust collecting cover 303, and a dust collecting chamber 306 is formed inside the dust collecting cover 303, and a dust collecting bag 305 that is joined to the suction port 304 is housed. An electric blower chamber 307 is formed behind the dust collecting chamber 306, and the electric blower 308 is housed. The intake side of the electric blower 308 is in communication with the dust collecting chamber 306 via the auxiliary filter 309. The exhaust side of the electric blower 308 is opened from the exhaust port 310 to the outside via the exhaust chamber and the exhaust filter. Further, the dust collecting chamber 306 may be used as a cyclone dust collecting.

Next, the electric blower 308 will be described with reference to FIGS. 3 to 7. Fig. 3 is a half longitudinal sectional view showing an embodiment of the electric blower of the present invention, Fig. 4 is a plan view showing the motor for cutting a part of the bracket 4, and Fig. 5 is a cross-sectional view showing the AA of Fig. 3, Fig. 6 It is a plan view of the diffuser 14, and Fig. 7 is a view showing the stationary flow path portion of the blower 1 such as the diffuser 14 and the return guide 15. This electric blower 308 is roughly classified into a blower 1 and an electric motor 2.

The motor 2 is composed of a motor casing, a motor rotor 6 (rotating member) housed in the motor casing having a rotating shaft 5, and a motor stator 8 (fixing member) wound with a stator coil 7. The motor The case is composed of a cylindrical outer casing 3 that is open at one end and a bracket 4 that is disposed on the opening side of the outer casing 3. The supply of electric power to the motor rotor 6 is transmitted by the brush unit 10 and the commutator 11 that is in contact therewith.

The motor stator 8 of the motor 2 has a substantially octagonal shape as viewed from the front, and four long sides 8a and four short sides 8b are alternately arranged, and four short sides 8b are fixed to the outer casing 3. In the inner side of the motor stator 8, a pair of stator coils 7 facing each other are wound. Four gate-shaped flow paths 20a and 20b are formed by the outer circumference of the four long sides 8a of the motor stator 8 and the inner diameter of the outer casing 3. The brush portion 10 is disposed on the downstream side of the flow path 20b on the side without the stator coil 7. The brush portion 10 is fixed to the outer casing 3 by bolts by the brush holder 10a. In the upstream side where the brush flow path 20b is disposed, the bracket 4 is fixed by a bolt, and the bearing 9 is held in the bracket 4 to support the rotating shaft 5.

The blower 1 includes a centrifugal fan 12, a fan casing 13 that houses the centrifugal fan 12, and a stationary flow path portion that has a return guide 15 on the diffuser 14 and the back surface of the diffuser 14.

The blower 1 includes a centrifugal fan 12 having a plurality of fins fixed by a nut 16 at an end portion of the rotating shaft 5, and a diffuser having a plurality of diffuser vanes 14a disposed on an outer peripheral side of the centrifugal fan 12. And an annular body 17 provided on the diffuser blade 14a (on the fan casing 13) side and a partition plate 18 provided on the lower side (the bracket 4) side of the diffuser 14 and formed thereon The return guide 15 of the plurality of return guide vanes 15a on the lower side (carrier 4) side of the partition plate 18, and the centrifugal fan 12, the diffuser 14, and the return guide 15 are encased and have air intake in the center. The port 13a is constituted by a fan casing 13 connected to the outer casing 3. In the fan casing 13, a sealing member 19 is disposed, which is slightly in contact with the centrifugal fan 12, and has a leakage preventing structure. In the present embodiment, the diffuser 14 having the plurality of diffuser blades 14a, the partitioning plate 18, and the return guide 15 having the plurality of return guide vanes 15a form a fixed guide vane from the centrifugal The fan 12 will be guided by the exhaust air to the air passage in the outer casing 3. Further, the annular body 17 may be provided as needed to form a fixed guide vane.

As shown in Fig. 6, the trailing edge of the diffuser vane 14a of the diffuser 14 is formed with a triangular window 14b (notch portion) which is located in the vicinity of the fan casing, from the outer peripheral end of the diffuser vane 14a along the diffuser thereof. A flow path of a slightly triangular recessed portion in which the surface on the outer peripheral side of the blade 14a faces inward.

The fan case 13 of the outer casing 3 and the fitting one end opening edge portion are projecting portions 3a which are curved toward the outer periphery, and the outer peripheral side end portion of the projecting portion 3a is bent toward the opening side of the outer casing 3 to form a substantially cylindrical shape. Mounting portion 3b. The fan case 13 is press-fitted into the mounting portion 3b of the outer casing 3, and is fixed to the outer casing 3.

An opening portion 21 that does not pass through the inside of the motor 2 to discharge the wind is formed in the protruding portion 3a of the outer casing 3. The opening portion 21 is opened in the axial direction of the rotating shaft 5 as shown in FIGS. 4 and 5, and the opening portion 21 is not provided in the protruding portion 3a on the upstream side of the flow path 20b at the position of the brush portion 10.

When the electric motor 2 is driven by the electric blower 308 having the above configuration, the air flowing in from the suction port 13a of the fan casing 13 is boosted and increased by the centrifugal fan 12. The air flow is discharged from the centrifugal fan 12 by the deceleration between the wings of the diffuser vane 14a, and the kinetic energy is converted into pressure energy to increase the pressure. The air flow is discharged from the diffuser 14, and the arrows in Fig. 6 and Fig. 7 show a slight 90° turn in the triangular window 14b. Thereafter, two air flows are branched, and a part thereof is discharged from the opening 21 of the outer casing 3 toward the outside of the outer casing 3. And the other side of the split is a further 90° turn, flowing into the return guide 15. The flow of the return guide 15 flows into the outer casing 3, and the motor rotor 6, the stator coil 7, the motor stator 8, the brush portion 10, and the commutator 11 in the outer casing 3 are cooled from the exhaust port 3c of the outer casing 3 toward the outside. It is discharged.

As shown in FIG. 4 and FIG. 5, since the opening portion 21 is not provided in the protruding portion 3a of the outer casing 3 on the upstream side of the flow path 20b at the position of the brush portion 10, the air flow from the diffuser 14 is large. The brush portion 10 flows in the flow path 20b among the four flow paths 20a and 20b having a gate shape. Further, since the flow path 20a of the brushless portion 10 has the opening portion 21, the amount of air exhausted toward the outside of the casing 3 is large, and it rarely flows in the flow path 20a.

The life of the motor 2 is related to the temperature of the brush portion 10 that is in contact with the commutator 11, and the life of the motor 2 can be extended by cooling the brush portion 10. According to the present embodiment, since the brush unit 10 can be efficiently cooled, the life of the brush unit 10 can be extended, that is, the life of the motor 2 can be extended. Further, since the cooling air volume is small in the flow path 20a having a small cooling relationship with the brush portion 10, the flow velocity in the flow path 20a is slow, and the loss can be reduced, and the blower efficiency can be improved.

In other words, the efficiency of the electric blower 308 can be improved, and the life of the electric motor 2 can be extended, and the electric blower 308 having high reliability can be obtained.

Therefore, by mounting the electric blower 308 on the cleaner body 201, the reliability of the vacuum cleaner is improved, and the suction operation rate can be improved.

As described above, in the present embodiment, the outer casing 3 on the upstream side of the flow path in which the brush unit 10 is disposed is formed among the four door-shaped flow paths 20a and 20b formed by the motor stator 8 and the outer casing 3 of the motor 2. Since the opening that does not discharge the wind by the motor is not formed, the airflow discharged from the diffuser 14 is in the flow path of the brush portion 10 among the four flow paths 20a and 20b that flow in a gate shape, and rarely It flows in the flow path of the brushless portion 10. Thereby, the brush unit 10 can be efficiently cooled, and the life of the motor 2 can be extended, and the reliability can be improved. Further, since the flow rate in the flow path having a small cooling relationship with the brush portion 10 is small, the flow velocity in the flow path is slow, and the loss can be reduced, and the blower efficiency can be improved.

[Embodiment 2]

Next, the embodiment of the present invention will be described using Fig. 8. Figure 8 is a cross-sectional view taken along line A-A of Figure 3. The same components as those of the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

In the above-described embodiment, the opening portion 21 that does not pass through the inside of the motor 2 in the protruding portion 3a of the outer casing 3 is not provided on the protruding portion 3a on the upstream side of the flow path 20b at the position of the brush portion 10. As shown in Fig. 8, the front side of the flow of the brush portion 10 is plugged in the protruding portion 3a on the upstream side of the flow path 20b at the position of the brush portion 10, and the position of the brush portion 10 is blocked. The rear side forms an opening portion 21.

Since the flow of the air flow discharged from the diffuser 14 is rotated, even if the front side of the flow of the wind at the portion of the brush portion 10 is blocked, the opening portion 21 is disposed from the position of the brush portion 10 toward the rear side. By maintaining the cooling effect of the brush unit 10, the cooling air of the flow path having a small cooling relationship can be exhausted to the outside of the casing 3, and the efficiency of the blower can be further improved. Therefore, the life of the electric motor 2 of the electric blower 308 can be extended, and the efficiency can be further improved.

The return guide 15 is composed of a plurality of return guide vanes 15a, and an air path is formed between the adjacent return guide vanes 15a. The wind that flows through this air passage flows from the outer peripheral side of the outer casing 5 toward the inner peripheral side. In addition, the wind is directed toward the four door-shaped flow paths 20a and 20b, but a part of the wind that faces the flow path 20a is discharged from the opening 21 formed in the middle of the flow path 20a toward the outside of the casing 3. The wind toward the flow path 20b is almost directed to the flow paths 20a, 20b. In the present embodiment, among the plurality of air passages formed between the adjacent return guide vanes 15a, the projections 3a that are directed toward the air passage position of the flow passage 20b that cools the brush portion 10 are not formed. Opening portion 21. With this configuration, the efficiency of the blower is improved, and the brush can be cooled.

In the first and second embodiments, the opening portion 21 is formed to be slightly more than 1/4 of the circumferential direction of the outer casing 3. The means for increasing the strength of the outer casing 3 is explained using Fig. 9. Figure 9 is a cross-sectional view taken along line A-A of Figure 3. The same components as those of the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted. Since the return guide vane 15a located below the diffuser 14 is provided across the opening portion 21, a part of the opening portion 21 is plugged by the return guide vane 15a.

In the present embodiment, a portion (the reinforcing portion 22) whose width is not equal to the opening which is equal to the width of the rotation center return guide vane 15a is provided at one position of the opening portion 21 at the position where the guide vane 15a is returned. Since the return guide vane 15a is closed by the opening portion 21 of the opening portion 21, since the portion having no opening is provided, the cooling performance can be not impaired, the strength of the outer casing 3 can be enhanced, and the electric blower 308 having high reliability can be further obtained.

[Example 3]

Next, the embodiment of the present invention will be described using FIG. Fig. 10 is a half longitudinal sectional view of the electric blower of the embodiment, and Fig. 11 is a perspective view of the diffuser 14 (the annular body 17 is not shown). The same components as those of the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The diffuser 14 is provided with a through hole 23 on the trailing edge side of all of the diffuser vanes 14a. By providing the through hole 23 in the diffuser vane 14a, the field of the convex side 24 of the diffuser vane 14a in which the boundary layer is developed and the area of the concave side 25 of the diffuser vane 14a which is close to the main flow of the boundary layer are connected to each other. . Since the pressure on the convex surface side 24 is higher than the concave surface side 25, the flow leaking from the convex surface side 24 toward the concave surface side 25 occurs, and the boundary layer of the convex surface side 24 is sucked out, and is discharged toward the main flow side of the concave surface side 25. As a result, the main flow that is biased toward the concave side 25 until now becomes the central portion of the flow path. Further, since the convex side 24 of the diffuser vane 14a is a wide opening of the triangular window 14b, the flow discharged from the diffuser 14 easily flows toward the triangular window 14b, and smooth flow can be smoothly performed, making it easy to open from the opening of the outer casing 3. 21 was exhausted. Therefore, the blower efficiency can be improved as compared with the case where the diffuser vane 14a has no through hole 23.

In addition, since the opening 21 is provided in the casing 3, the noise generated from the centrifugal fan 12 is directly emitted from the fan casing 13 to the outside, and the noise of the electric blower 308 and the electric vacuum cleaner on which it is mounted increases. However, since the sound waves passing through the diffuser vanes 14a pass through the through holes 23 by the through holes 23 provided in the diffuser vanes 14a, the noise of the electric blower itself can be reduced by the interference of both sides of the diffuser vanes 14a. . Therefore, even if the outer casing 3 has the opening portion 21, noise reduction can be achieved, and noise reduction and efficiency improvement can be achieved.

Therefore, by mounting the electric blower 308, the noise of the electric vacuum cleaner can be reduced.

[Industry use possibility]

As described above, the electric blower of the present invention and the electric vacuum cleaner provided therewith can improve the reliability of the electric blower and improve the efficiency. Therefore, the reliability of the electric vacuum cleaner and the improvement of the suction operation rate can be achieved. Further, it can be widely applied to applications such as household electric equipment and industrial equipment using an electric blower.

1. . . Blower

2. . . electric motor

3. . . shell

3a. . . Protruding

3b. . . Installation department

3c. . . exhaust vent

4. . . bracket

5. . . Rotary axis

6. . . Motor rotor

7. . . Stator coil

8. . . Motor stator

8a. . . Long side of the outer circumference of the motor stator

8b. . . Short side of the outer circumference of the motor stator

9. . . Bearing

10. . . Brush department

10a. . . Brush holder

11. . . Commutator

12. . . Centrifugal fan

13. . . Fan housing

13a, 304. . . suction point

14. . . Diffuser

14a. . . Diffuser blade

15. . . Return guide

15a. . . Return guide vane

16. . . Nut

17. . . Ring

18. . . Partition plate

19. . . Sealing member

20a, 20b. . . Flow path

twenty one. . . Opening

twenty two. . . Reinforcement department

twenty three. . . Through hole

201. . . Vacuum cleaner body

202. . . tube

203. . . Hand operation department

204. . . Extension tube

205. . . Suction body

206. . . Switch operation unit

301. . . Lower case

302. . . Upper shell

303. . . Dust cover

305. . . Dust bag

306. . . Dust chamber

307. . . Electric blower room

308. . . Electric blower

309. . . Subsidy filter

310. . . exhaust vent

[Fig. 1] An external perspective view of an electric vacuum cleaner according to an embodiment of the present invention.

Fig. 2 is a longitudinal sectional view showing a cleaner body according to an embodiment of the present invention.

[Fig. 3] A half longitudinal sectional view of an electric blower according to an embodiment of the present invention.

[Fig. 4] A plan view of a motor in which a part of the bracket of Fig. 3 is cut.

[Fig. 5] A-A section of Fig. 3.

[Fig. 6] A plan view of the diffuser.

[Fig. 7] A view showing the stationary flow path portion of the blower.

Fig. 8 is a plan view showing an electric motor of an electric blower according to an embodiment of the present invention.

Fig. 9 is a plan view showing a motor of an electric blower according to an embodiment of the present invention.

Fig. 10 is a half longitudinal sectional view showing an electric blower according to an embodiment of the present invention.

[Fig. 11] A perspective view of the diffuser.

3a. . . Protruding

3b. . . Installation department

4. . . bracket

5. . . Rotary axis

7. . . Stator coil

8. . . Motor stator

8a. . . Long side of the outer circumference of the motor stator

8b. . . Short side of the outer circumference of the motor stator

10. . . Brush department

10a. . . Brush holder

20a, 20b. . . Flow path

twenty one. . . Opening

Claims (3)

An electric blower comprising: a motor provided with a rotating member and a fixing member; and at least one pair of brush portions that slide with the rotating member, and one end opening and accommodating the motor and the brush portion inside a casing, a rotating shaft provided on the rotating member, a centrifugal fan attached to the rotating shaft, and a diffuser that guides the air discharged from the centrifugal fan to a flow path in the casing, and the diffuser a fan casing that is attached to the outer casing and has a suction port at a central portion thereof, and a protruding portion that protrudes toward the outer peripheral side is formed in the opening side of the outer casing, and the protruding portion is formed in the protruding portion The opening portion through which the air is discharged forms four flow paths from the outer periphery of the fixing member and the inner diameter of the outer casing, and the pair of brush portions are respectively located in two of the four flow paths, below the diffuser Providing a return guide formed by a plurality of curved return guide vanes, wherein an air path is formed between the adjacent return guide vanes, and among the protruding portions, The opening portion is not provided in the air passage position portion of the flow path in which the brush portion is provided, and the opening portion is provided in the air passage position portion of the flow path in which the brush portion is not provided. Returning to at least one position of the aforementioned opening portion of the guide vane position, a portion that is not opened is provided. An electric blower comprising: a motor provided with a rotating member and a fixing member; and at least one pair of brush portions that slide with the rotating member, and one end opening and accommodating the motor and the brush portion inside a casing, a rotating shaft provided on the rotating member, a centrifugal fan attached to the rotating shaft, and a diffuser that guides the air discharged from the centrifugal fan to a flow path in the casing, and the diffuser a fan casing that is attached to the outer casing and has a suction port at a central portion thereof, and a protruding portion that protrudes toward the outer peripheral side is formed in the opening side of the outer casing, and the protruding portion is formed in the protruding portion In the opening portion through which the air is discharged, four flow paths are formed by the outer periphery of the fixing member and the inner diameter of the outer casing, and the pair of brush portions are respectively located in two of the four flow paths, and the diffuser has a plurality of The diffuser vane is provided with an annular body on the upper side of the diffuser vane, a partition plate on the lower side of the diffuser, and a plurality of curved shapes on the lower side of the partition plate. Returning to the return guide of the guide vane, a through hole is formed on the trailing edge side of the diffuser vane, and an air passage is formed between the adjacent return guide vanes, and the protruding portion is provided in the front direction The opening portion is not provided in the air passage position portion of the flow path of the brush portion, and the opening portion is provided in the air passage position portion of the flow path in which the brush portion is not provided, and the return guide is provided. At least one position of the aforementioned opening portion of the blade position is provided with a portion that is not opened. An electric vacuum cleaner comprising: an electric blower chamber for accommodating the electric blower according to the first or second aspect of the patent application; and a cleaner body that houses the dust collecting chamber; and a tube whose one end is connected to the cleaner body And a hand operating portion connected to the other end of the tube, an extension tube having one end connected to the other end of the hand operation portion, and a mouthpiece connected to the other end of the extension tube.