JP4729599B2 - Electric blower and vacuum cleaner equipped with the same - Google Patents

Description

  The present invention relates to an electric blower and a vacuum cleaner provided with the same.

  A conventional electric blower is disclosed in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 54-105307). In Patent Document 1, a partition plate is provided on the back side of an impeller (centrifugal fan), and a diffuser vane (diffuser vane) is provided on the front surface of the partition plate and on the outer peripheral side of the impeller. Discloses an electric blower in which a cut is provided from the front side (the side opposite to the partition plate).

  Further, as another conventional technique, for example, there is Patent Document 2 (Japanese Patent Laid-Open No. Hei 8-242553). Patent Document 2 discloses an electric blower in which an air guide (diffuser) is provided on the outer peripheral side of an impeller (centrifugal fan) and one or a plurality of through holes are provided in a blade portion of the air guide.

JP 54-105307 A JP-A-8-242553

  In Patent Document 1, a noise is reduced by providing a cut in the diffuser vane from the front surface side (the non-partition plate side). The diffuser is provided to decelerate the flow from the centrifugal fan and restore the dynamic pressure to static pressure. However, in Patent Document 1, the flow from the notch hinders the deceleration of the main flow flowing between the diffuser and the vane, and the pressure is reduced. There was a problem that the recovery could not be performed sufficiently and the efficiency of the blower decreased.

  In Patent Document 2, one or a plurality of through holes of a centrifugal fan are provided. However, as in Patent Document 1, the flow from the through holes hinders the deceleration of the main flow flowing between the diffuser and the vane, thereby restoring the pressure. However, there is a problem that the efficiency of the blower decreases.

  In Patent Documents 1 and 2, no consideration has been given to the position of the through hole in consideration of the fan efficiency.

  The object of the present invention is to solve the above-mentioned problems, to reduce the noise of the blower, and to provide an electric blower that improves the efficiency of the blower and a vacuum cleaner equipped with the electric blower.

In order to achieve the above object, the present invention is characterized in that an electric motor including a rotor and a stator, a housing that is open at one end and accommodates the electric motor, and a rotary shaft provided in the rotor A centrifugal fan fixed to the rotating shaft, a partition plate disposed on the back side of the centrifugal fan, a diffuser disposed on the front surface side of the partition plate and on the outer peripheral side of the centrifugal fan, In the electric blower comprising: a return guide disposed on the rear surface side of the partition plate; and a fan casing provided on the opening side of the housing and covering the centrifugal fan, the diffuser, and the return guide, the diffuser includes a plurality of diffusers weight with wings, at least a portion of the diffuser vanes of the plurality of diffuser vanes, formed by being sandwiched between the diffuser vanes both adjacent Ri portions to the other of the diffuser vanes between the outlet end face of the one of the diffuser vanes of the air flow passage position to plus an open end correction value [delta], through holes rising from said partition plate is formed of the through hole The height is that the height of the diffuser blade is set to ½ or less .
Alternatively, a feature of the present invention is that an electric motor including a rotor and a stator, a housing that is open at one end and accommodates the electric motor inside, a rotating shaft provided in the rotor, and the rotating shaft A centrifugal fan fixed to the centrifugal fan, a partition plate disposed on the back side of the centrifugal fan, a diffuser disposed on the front surface side of the partition plate and on the outer peripheral side of the centrifugal fan, and an anti-partition plate of the diffuser An annular plate disposed on the side, a return guide disposed on the rear side of the partition plate, and a fan casing provided on the opening side of the housing and covering the centrifugal fan, the diffuser, the return guide, and the annular plate The diffuser includes a plurality of diffuser blades, is integrally formed with the annular plate, and includes at least one of the plurality of diffuser blades. The other diffuser blade is located between the outlet end surface of one diffuser blade of the overlapping portion air flow passage formed between both of the adjacent diffuser blades and the position to which the opening end correction value δ is added. The diffuser blade is provided with a notch cut out from the anti-annular plate side, and the diffuser is joined to the partition plate, whereby the notch is formed as a through hole, and the height of the through hole is determined by the diffuser blade. The height is set to 1/2 or less.

  ADVANTAGE OF THE INVENTION According to this invention, while reducing the noise of an air blower, the electric blower which aimed at the efficiency improvement of the air blower, and the vacuum cleaner provided with this electric air blower can be provided.

  FIG. 12 shows an external perspective view of a vacuum cleaner according to one embodiment of the present invention. Reference numeral 101 denotes a dust collecting chamber for collecting dust and a vacuum cleaner main body that houses an electric blower that generates a suction air flow necessary for collecting dust, and 102 has one end connected to the cleaner main body 101 via a hose joint 102a. A hose, 103 is a hand operating part whose one end is connected to the other end of the hose 102, 104 is an extension pipe connected to the other end of the hand operating part 103, and 105 is a suction port connected to the other end of the extension pipe 104 Is the body. 103a is a switch unit for turning on and off the electric blower provided in the hand operation unit 103.

  Next, the structure of the cleaner main body 101 is shown using FIG. FIG. 11 is a cross-sectional view of a cleaner body according to an embodiment of the present invention. In FIG. 11, 110 is a dust collection chamber formed on the front side of the cleaner body 101, 111 is provided in the dust collection chamber 110 and collects dust, and 112 is formed on the rear side of the cleaner body 101. The electric blower chamber 113 and 113 are provided in the electric blower chamber 112 and generate an attractive force. Reference numeral 114 denotes an anti-vibration rubber that supports the electric blower 113, and 115 denotes a filter unit disposed between the dust collection chamber and the electric blower 113.

  In the above configuration, when the switch unit 103a of the hand operation unit 103 is operated, the electric blower 113 housed in the cleaner body 101 is operated to generate a suction airflow. Then, dust is sucked from the suction body 105 and collected in the dust collection bag 111 disposed in the dust collection chamber 110 of the cleaner body 101 through the extension pipe 104, the hand operation unit 103, and the hose 102. In the present embodiment, the vacuum cleaner in which the dust collection bag 111 is disposed in the dust collection chamber 110 is illustrated, but a cyclone dust collection unit using centrifugal separation may be attached to the dust collection chamber 110.

  Next, the configuration of the electric blower 113 will be described with reference to FIG. FIG. 10 is a longitudinal sectional view of the electric blower 113 according to one embodiment of the present invention. The electric blower 113 includes a blower unit 11 and an electric motor unit 12.

  The motor unit 12 constitutes an outer shell of the motor by a housing 13 having one end opened and an end bracket 14 disposed on the opening side of the housing 13. The rotating shaft 15 of the rotor 16 is rotatably supported by the opposite opening side of the housing 13 and the end bracket 14, and the rotor 16 is attached to the rotating shaft 15. A stator 17 is arranged on the outer peripheral side of the rotor 16. The supply of electricity to the rotor 16 is transmitted by a brush 18 and a commutator 19 that contacts the brush 18. A rotor 16, a stator 17, and a brush 18 are accommodated in the housing 13.

  The blower unit 11 is fixed to the rotary shaft 15 and has a centrifugal fan 20 having a suction port 20a, a diffuser 21 disposed on the outer peripheral side of the centrifugal fan 20, and a partition plate 23 sandwiched between the diffuser 21 and the blower unit 11. A return guide 25 arranged in a facing manner is housed in a fan casing 26. The fan casing 26 is disposed on the opening side of the housing 13 and covers the centrifugal fan 20, the diffuser 21, and the return guide 25. The partition plate 23 is located on the back side (anti-suction port side) of the centrifugal fan 20. A diffuser 21 is disposed on the front surface side of the partition plate 23, and a return guide 25 is disposed on the rear surface side of the partition plate 23. An annular plate 27 is disposed on the side of the diffuser 21 opposite to the partition plate.

  In this configuration, the air flowing in from the blower inlet 10 is first boosted and accelerated by the centrifugal fan 20. Thereafter, the flow that has passed through the diffuser 21 turns approximately 180 ° through the curved flow path 24 and flows into the return guide 25. In this process, the flow is decelerated, and the pressure increases accordingly. The flow that has passed through the return guide 25 flows into the housing 13 of the electric motor, and is discharged after cooling the rotor 16, the stator 17, the brush 18, the commutator 19, and the like.

  FIG. 9 illustrates the configuration of the diffuser 21. FIG. 9 is a view of the diffuser 21 as viewed from the blower inlet 10 side which is the axial direction of the rotary shaft 15. As shown in FIG. 9, the diffuser 21 has a plurality of (the number of) diffuser blades 22 arranged on the front side of the partition plate 23 so that the air discharged from the centrifugal fan 20 passes between the adjacent diffuser blades 22. It has become. Here, the diffuser blades 22 have an arc shape, and are formed so as to increase the distance between adjacent diffuser blades 22 from the inlet side to the outlet side of the flow, and the flow is decelerated as the wind passes therethrough. The pressure recovers.

  The rear edge of the diffuser blade 22 is located in the vicinity of the fan casing 26. A substantially triangular triangular window 51 is formed between the rear edge of the diffuser blade 22 and the fan casing 26 and is cut out toward the inside of the diffuser 21. The wind that exits between the diffuser blades 22 turns in the vertical direction through the triangular window 51 and flows toward the return guide 25. Here, the convex side 52 and the concave side 53 of the diffuser blade 22 are defined as shown in the figure, and the region surrounded by the adjacent blades in the inter-blade channel is the overlapping portion 54 and the outlet side region facing only the one blade. Is defined as the outlet-side half-opening portion 55.

  Next, the flow between the diffuser blades 22 in the diffuser 21 will be described with reference to FIGS. 7 and 8. 7 is a partially enlarged view of the blower unit 11, and FIG. 8 is a cross-sectional view of the diffuser 21 in FIG. 8A is a cross-sectional view taken along line AA in FIG. 7, FIG. 8B is a cross-sectional view taken along line BB in FIG. 7, and FIG. 8C is a cross-sectional view taken along line CC in FIG. .

  7 and 8, the partition plate 23 side is defined as the hub side, and the suction port 20a side of the centrifugal fan 20 is defined as the shroud side. Accordingly, FIG. 8A shows the flow of wind between the diffuser blades 22 on the hub side, FIG. 8C shows the flow of wind between the diffuser blades 22 on the shroud side, and FIG. The flow of the wind between the diffuser blades 22 at the center in the height direction of the diffuser blades 22 in the middle of the shroud side is shown.

  As is apparent from FIG. 8, when the hub-side main flow 81, the central cross-section main flow 82, and the shroud-side main flow 83 are viewed, the main flow of wind flowing between the diffuser blades 22 is biased toward the concave surface side of the diffuser blades 22. The fast flow was concentrated. On the other hand, it can be seen that a boundary layer develops on the convex side, and the flow is slow. From this, it can be seen that effective channel expansion is not realized between the diffuser blades 22 and pressure recovery is not sufficiently performed. This tendency is particularly prominent on the hub side shown in FIG. 8A, and becomes smaller from the central portion toward the shroud side. The present inventors have found that there is a difference in flow turbulence in the height direction of the diffuser blade 22. As described above, effective expansion of the flow path is not realized between the diffuser blades 22 and pressure recovery is not sufficiently performed. Therefore, noise is generated in the blower and the efficiency of the blower is reduced. In order to improve this, it is particularly necessary to improve the flow on the hub side. Hereinafter, means for solving this will be described with reference to FIGS.

  FIG. 1 is an overall perspective view of a diffuser 21 according to an embodiment of the present invention, and FIG. 2 is a partially enlarged view of the diffuser 21 according to an embodiment of the present invention viewed from the direction of the rotating shaft 15 of the motor. 3 is a mathematical formula for obtaining the position of the through hole 40 of the diffuser 21 according to one embodiment of the present invention.

  In FIG. 1, the partition plate 23 is provided with a plurality of (sheets) diffuser blades 22 rising from the partition plate 23. The diffuser blade 22 has a through hole 40 that rises from the partition plate 23 to a predetermined height. The through hole 40 is formed so as to penetrate between the adjacent flow paths 56. That is, the through hole 40 is formed on the hub side. Further, the through hole 40 is positioned in the vicinity of the triangular window 51 (notch) where the flow is changed toward the return guide 25.

  Next, the flow between the diffuser blades 22 in the diffuser 21 when the through hole 40 is provided will be described with reference to FIG. 4 is a cross-sectional view of the diffuser 21 in FIG. 4A is a cross-sectional view taken along the line AA in FIG. 7, FIG. 4B is a cross-sectional view taken along the line BB in FIG. 7, and FIG. 4C is a cross-sectional view taken along the line CC in FIG. .

  In FIG. 4A, when the through hole 40 is provided, a leakage flow is generated from the convex surface side of the blade toward the concave surface side through the through hole 40. For this reason, on the hub surface side where the through-hole 40 exists, the boundary layer seen in FIG. 8A is sucked to the opposite side (concave surface) of the blade, and the main flow is caused by the sucked flow. It can be seen that it is turned in the left direction of the drawing. An effective flow path expansion is realized between the diffuser blades 22 and pressure recovery is performed. 4B and the flow on the shroud side in FIG. 4C are not as much as the flow on the hub side in FIG. 4A, but are affected by the flow turning on the hub side. An effective flow path expansion is realized between the diffuser blades 22. As described above, in the present embodiment, by providing the through hole 40 on the hub side, effective flow path expansion between the diffuser blades 22 is realized on the hub side, the central portion, and the shroud side, and pressure recovery is performed. . As a result, the efficiency of the blower can be improved while reducing noise.

  Further, when the diffuser 21 and the return guide 25 are separated as in the present embodiment, and the triangular window 51 (notch portion) exists between them, the triangular window is wider on the convex side of the wing. Since it is open, turning the hub side flow in this wide area has the effect of realizing a smooth bending flow.

  The through hole 40 is opened immediately before the inflow into the triangular window 51 that becomes a bent portion, but due to the flow through the through hole 40, the inflow inlet side (convex surface side) becomes a negative pressure from the surroundings due to suction force. Therefore, the inter-blade flow has an effect of being bent by being drawn toward the through hole 40, and thus has an effect of supporting the bending flow connected to the return guide 25.

  Thus, the fan efficiency can be improved by enlarging the effective enlarged flow path area by three-dimensional deflection of the main flow flowing in the diffuser and realizing the smooth bending flow from the diffuser to the return guide.

  For this example, it has been experimentally confirmed that by taking the above mechanism into consideration, it is possible to expect further effects especially by providing the following conditions. In other words, the height (h) of the through hole 40 shown in FIG. 1 is desirably ½ or less of the diffuser height (H), that is, h ≦ H / 2. These heights are measured at the radial positions where the through holes 40 are opened. Moreover, although the shape of the through-hole 40 is shown as a rectangle in FIG. 1, it is not limited to this, and other shapes, such as a trapezoid and a circle, may be sufficient. In FIG. 2, a perpendicular line (b) perpendicular to the tangent line (a) in the through hole 40 of the diffuser blade 22 is used, and the angle difference between the perpendicular line (b) and the center line of the through hole 40 is the through hole angle difference ( θ). In this embodiment, the through-hole angle difference (θ) is set to 0 ° ≦ θ ≦ 45 °. This is because by setting this angle, the merging of the leakage flow through the through hole 40 and the main flow becomes smooth.

  Next, the position of the through hole 40 of the diffuser 21 is obtained using FIG. In obtaining the position of the through hole 40, for example, the technique disclosed in Japanese Patent No. 3510107 may be used.

The through hole 40 formed in the diffuser blade 22 has a diffuser between the outlet end surface 61 of the overlapping portion 54 (FIG. 9) of the diffuser blade 22 and the position 62 at a distance δ on the outlet side half-opened portion 55 (FIG. 9). It is formed on the surface of the wing 22. The correction value δ is calculated from the following equation. The correction value δ is set such that a and b are side dimensions in the rectangular section of the outlet of the overlapping portion air flow channel,
a> b
When the following equation (Equation 1)

The distance obtained by.

  The air flow in the diffuser 21 passes through the overlapping portion 54 and passes through the outlet half-opening portion 55. In the overlapping portion 54 of the diffuser, the generated sound wave becomes a plane wave and propagates in the flow direction. However, since the channel cross-sectional area increases discontinuously at the overlapping portion outlet end face 30, the acoustic impedance changes at this position. At the position where the acoustic impedance changes, the sound wave that has been propagated along the flow so far is reflected, and this time becomes a reflected wave, and on the contrary, propagates upstream through the flow. Even at the position of the upstream overlap portion entrance, the acoustic impedance changes because the cross-sectional area changes. Therefore, the reflected wave propagating toward the upstream side is reflected again at the overlapping portion entrance.

  In this way, the sound wave generated at the tip of the diffuser blade propagates downstream, reflects back and repeats the process of reflection again, but the period of this round-trip reflection is the original incident light. When it coincides with the generation period of the sound wave, resonance occurs in the overlapping portion, and the emitted sound becomes large.

  Thus, on the outlet end face 30 of the overlapping portion 34, the pressure fluctuation of the sound wave is 0, that is, a standing wave node. To be precise, the node of the standing wave is generated at a position 31 obtained by adding a distance δ which is an opening end correction value from the exit end face 30 of the overlapping portion 34. The above-described mathematical expression is an expression for obtaining the value of the opening end correction value δ.

  FIG. 5 shows an example of a result obtained by experimentally verifying changes in the efficiency and noise of the electric blower depending on the presence / absence of the through hole 40 and the formation position of the through hole. Here, the electric blower efficiency is defined by the following formula.

Electric blower efficiency η = output / input
Output = ρgQH
(Ρ: density, g: acceleration of gravity, Q: air volume, H: pressure)
In FIG. 5, (1) is a case where no through hole 40 is provided, (2) is a case where the through hole 40 is raised from the hub side and is formed up to half the height of the diffuser blade, and (3) is a through hole 40. Is shown when the shroud is cut away from the shroud side toward the hub side.

  First, looking at the efficiency of the electric blower, as is clear from FIG. 5A, the through hole 40 is raised from the hub side as in this embodiment, compared to the case (1) in which the through hole 40 is not provided. It can be seen that the efficiency of the electric blower is improved when it is formed to a height of 1/2 of the diffuser blade (2). Moreover, when the through-hole 40 is notched toward the hub side from the shroud side (3), it turns out that the efficiency of an electric blower has fallen compared with the case (1) which does not provide the through-hole 40. Thus, it can be seen that the efficiency of the electric blower varies greatly depending on the position where the through hole 40 is formed.

  Next, when looking at the noise, as is clear from FIG. 5B, compared to the case (1) in which the through hole 40 is not provided, the through hole 40 is raised from the hub side as in this embodiment, and the diffuser blade It can be seen that the blade sound (peak sound) is reduced when the height is 1/2 (2). In addition, when the through hole 40 is notched from the shroud side to the hub side (3), it can be seen that the blade sound (peak sound) is lower than when the through hole 40 is not provided (1). . Further, as in the present embodiment, when the through hole 40 is raised from the hub side and formed to a height of 1/2 of the diffuser blade (2), and when the through hole 40 is cut from the shroud side toward the hub side In (3), it can be seen that the blade sound (peak sound) is at substantially the same level. It can be seen that the through hole 40 greatly affects noise reduction, that is, reduction of blade noise (peak noise). Thus, it can be seen that the efficiency of the electric blower varies greatly depending on the position where the through hole 40 is formed.

  As described above, in this embodiment, the diffuser blade 22 rises from the partition plate 23 to a predetermined height to form the through hole 40, so that the efficiency of the electric blower is improved while reducing the noise of the blower. Is something that can be done.

  Next, a manufacturing method of the diffuser 21, the partition plate 23, and the return guide 25 provided with the through holes 40 will be described with reference to FIG. FIG. 6 is a diagram illustrating a production method of the diffuser 21, the partition plate 23, and the return guide 25 according to an embodiment of the present invention.

  In FIG. 6, reference numeral 27 denotes an annular plate that is arranged on the side opposite to the partition plate of the diffuser 21 and is formed in a ring shape. A plurality of diffuser blades 22 are provided on the side of the annular plate 27 facing the partition plate 23. Further, the diffuser blade 22 is formed with a notch 22a that becomes a through hole 40 that is notched from the anti-annular plate side.

  In the present embodiment, the annular plate 27, the diffuser blade 22, and the notch 22a are integrally formed of resin or the like. In forming the annular plate 27, the diffuser blade 22, and the notch 22a, it is only necessary to prepare a mold that can be removed in the vertical direction, the mold structure is simple, and productivity is improved.

  The disc-shaped partition plate 23 is provided with a return guide 25 on the anti-diffuser blade 22 side (the rear surface side of the partition plate 23). The return guide 25 includes a plurality of (return) return guide blades 25a.

  In this embodiment, the partition plate 23 and the return guide blade 25a are integrally formed of resin or the like. In forming the partition plate 23 and the return guide blade 25a, it is only necessary to prepare a mold that can be removed in the vertical direction, the mold structure is simple, and productivity is improved.

  Next, the anti-annular plate 27 side of the diffuser blade 22 and the diffuser blade 22 side of the partition plate 23 (the front side of the partition plate 23) are aligned and joined. As a bonding method, ultrasonic welding, an adhesive, or the like that uses high frequency to weld the resin is used. What is necessary is just to select the joining method suitably. A through hole 40 is formed in the diffuser blade 22 by joining the anti-annular plate 27 side of the diffuser blade 22 to the diffuser blade 22 side of the partition plate 23. The through hole 40 is formed in a state of rising from the partition plate 23.

  Normally, when the through hole 40 is formed in a state where it rises from the partition plate 23, it is necessary to use a slide mold for forming the through hole 40 or to perform an additional process using a drill or the like. On the other hand, in the present embodiment, the annular plate 27, the diffuser blade 22 and the notch 22a are integrally formed, and the partition plate 23 and the return guide blade 25a are integrally formed, and these are joined. The through hole 40 can be formed in the diffuser blade 22 without using a complicated mold.

  As described above, according to the present embodiment, it is possible to provide an electric blower that reduces the noise of the blower and improves the efficiency of the blower, and a vacuum cleaner including the electric blower.

In the present embodiment, the electric blower for a vacuum cleaner has been described, but the present invention is not limited to this. What is necessary is just to apply to various products as needed.

1 is an overall perspective view of a diffuser 21 according to an embodiment of the present invention. It is the elements on larger scale which looked at the diffuser 21 which concerns on one Example of this invention from the rotating shaft 15 direction of the electric motor. It is a numerical formula for calculating | requiring the position of the through-hole 40 of the diffuser 21 which concerns on one Example of this invention. It is sectional drawing of the diffuser 21 in FIG. It is an experimental result which shows the change of the efficiency and noise of an electric blower. It is a figure explaining the production method of the diffuser 21, the partition plate 23, and the return guide 25 which concern on one Example of this invention. It is the elements on larger scale of the air blower part. It is sectional drawing of the diffuser 21 in FIG. It is the figure which looked at the diffuser 21 from the air blower inlet 10 side which is the axial direction of the rotating shaft 15. FIG. It is a longitudinal cross-sectional view of the electric blower 113 which concerns on one Example of this invention. It is a cross-sectional view of a cleaner body according to an embodiment of the present invention. 1 is an external perspective view of a vacuum cleaner according to an embodiment of the present invention.

Explanation of symbols

21 Diffuser 22 Diffuser blade 23 Partition plate 25 Return guide 25a Return guide blade 40 Through hole

Claims (6)

An electric motor including a rotor and a stator, a housing having one end opened and housing the electric motor therein, a rotating shaft provided in the rotor, a centrifugal fan fixed to the rotating shaft, and the centrifugal fan A partition plate disposed on the rear side of the partition plate, a diffuser disposed on the front surface side of the partition plate and disposed on the outer peripheral side of the centrifugal fan, a return guide disposed on the rear surface side of the partition plate, In the electric blower provided on the opening side and provided with the centrifugal fan, the diffuser, and a fan casing that covers the return guide,
The diffuser comprises a plurality of diffuser blades,
An opening end correction value δ is added to at least some of the diffuser blades of the plurality of diffuser blades from the exit end face of one of the diffuser blades of the overlapping portion air flow passage formed between both of the adjacent diffuser blades. In the other diffuser blade until the position, a through hole rising from the partition plate is formed ,
The electric blower characterized in that the height of the through hole is ½ or less of the height of the diffuser blade . In claim 1,
The opening end correction value δ is set to a and b as the dimensions of the sides in the rectangular cross section of the outlet of the overlapping portion air flow channel,
a> b
When the following equation (Equation 1)

The electric blower characterized by being a distance obtained by An electric motor including a rotor and a stator, a housing having one end opened and housing the electric motor therein, a rotating shaft provided in the rotor, a centrifugal fan fixed to the rotating shaft, and the centrifugal fan A partition plate disposed on the back side of the diffuser, a diffuser disposed on the front surface side of the partition plate and disposed on the outer peripheral side of the centrifugal fan, an annular plate disposed on the counter partition plate side of the diffuser, and the partition In the electric blower comprising a return guide disposed on the rear side of the plate, and a fan casing provided on the opening side of the housing and covering the centrifugal fan, the diffuser, the return guide, and the annular plate,
The diffuser includes a plurality of diffuser blades and is integrally formed with the annular plate,
An opening end correction value δ is added to at least some of the diffuser blades of the plurality of diffuser blades from the exit end face of one of the diffuser blades of the overlapping portion air flow passage formed between both of the adjacent diffuser blades. The other diffuser blade between the two positions is provided with a notch cut out from the anti-annular plate side,
By joining the diffuser to the partition plate, the notch is a through hole ,
The electric blower characterized in that the height of the through hole is ½ or less of the height of the diffuser blade . A vacuum cleaner main body that houses the dust collection chamber and the electric blower, a hose with one end connected to the vacuum cleaner main body, a hand operating part with one end connected to the other end of the hose, and one end with the hand operating part In a vacuum cleaner comprising an extension pipe connected to the other end and a suction body connected to the other end of the extension pipe,
The electric blower is
An electric motor including a rotor and a stator, a housing having one end opened and housing the electric motor therein, a rotating shaft provided in the rotor, a centrifugal fan fixed to the rotating shaft, and the centrifugal fan A partition plate disposed on the rear side of the partition plate, a diffuser disposed on the front surface side of the partition plate and disposed on the outer peripheral side of the centrifugal fan, a return guide disposed on the rear surface side of the partition plate, A fan casing provided on the opening side and covering the centrifugal fan, the diffuser, and the return guide ;
The diffuser comprises a plurality of diffuser blades,
An opening end correction value δ is added to at least some of the diffuser blades of the plurality of diffuser blades from the exit end face of one of the diffuser blades of the overlapping portion air flow passage formed between both of the adjacent diffuser blades. In the other diffuser blade until the position, a through hole rising from the partition plate is formed ,
The vacuum cleaner characterized in that the height of the through hole is not more than ½ of the height of the diffuser blade . A vacuum cleaner main body that houses the dust collection chamber and the electric blower, a hose with one end connected to the vacuum cleaner main body, a hand operating part with one end connected to the other end of the hose, and one end with the hand operating part In a vacuum cleaner comprising an extension pipe connected to the other end and a suction body connected to the other end of the extension pipe,
The electric blower is
An electric motor including a rotor and a stator, a housing having one end opened and housing the electric motor therein, a rotating shaft provided in the rotor, a centrifugal fan fixed to the rotating shaft, and the centrifugal fan A partition plate disposed on the back side of the diffuser, a diffuser disposed on the front surface side of the partition plate and disposed on the outer peripheral side of the centrifugal fan, an annular plate disposed on the counter partition plate side of the diffuser, and the partition A return guide disposed on the rear surface side of the plate, and a fan casing provided on the opening side of the housing and covering the centrifugal fan, the diffuser, the return guide, and the annular plate ,
The diffuser includes a plurality of diffuser blades and is integrally formed with the annular plate,
An opening end correction value δ is added to at least a part of the diffuser blades of the plurality of diffuser blades from the exit end face of one of the diffuser blades of the overlapping portion air flow passage formed between both of the adjacent diffuser blades. The other diffuser blade between the two positions is provided with a notch cut out from the anti-annular plate side,
By joining the diffuser to the partition plate, the notch is a through hole ,
The vacuum cleaner characterized in that the height of the through hole is not more than ½ of the height of the diffuser blade . In claim 4,
The opening end correction value δ is set to a and b as the dimensions of the sides in the rectangular cross section of the outlet of the overlapping portion air flow channel,
a> b
When the following equation (Equation 1)

A vacuum cleaner characterized by being a distance required by

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