JP2005220853A - Electric blower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric blower having improved blowing efficiency by improving a diffuser opposed to a fan. <P>SOLUTION: A downstream side end 42a of each stator blade 42 of the diffuser 15 consists of a first edge E1 and a second edge E2 ranging therefrom. The first edge E1 is put in close contact with the inner face of a fitting cylinder portion 52 of a fan cover 16 fitted to the diffuser 15, while the second edge E2 is put in close contact with the inner face of a corner portion 16b formed between a stator blade pressure portion 53 of the fan cover 16 and the fitting cylinder portion 52. Thus, outlet portions P2 of diffuser air paths P neighboring each other at the downstream side ends 42a of the stator blades 42 are partitioned from each other to suppress the disturbance of air streams due to their mutual interference at the outlet portions P2 of the diffuser air paths P. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electric blower that is mounted on, for example, an electric vacuum cleaner and performs a blowing action by rotating a fan by a rotational force obtained by an electric motor unit.

  2. Description of the Related Art Conventionally, various types of electric blowers have been provided in which a diffuser is disposed between an electric motor section and a fan covered with a fan cover to guide the wind discharged from the fan while reducing the static pressure. Among them, by providing a diffuser having a large number of stationary blades arranged around the fan so as to face the discharge port of the fan, the air discharged from the fan is formed between the stationary blades. There is known an electric blower that makes a static pressure in the diffuser air passage (see, for example, Patent Document 1).

The fan cover of the electric blower disclosed in Patent Document 1 includes a fitting cylinder part, a fan facing part facing the front shroud of the fan, and a stationary blade presser provided with the fan facing part and the fitting cylinder part continuously provided. Part. And the stationary blade pressing part is in close contact with the edge extending along the flow direction of the wind passing through the diffuser air passage of each stationary blade facing the fan. However, the edge of the downstream end of each stationary blade is away from the inner surface of the corner portion of the fan cover and the inner surface of the fitting cylinder portion formed over the fitting cylinder portion and the stationary blade presser portion, It was not given. In other words, in the electric blower described in Patent Document 1, a gap is formed between the downstream end of each stationary blade facing the fan and the inner surface of the fitting tube portion and the inner surface of the corner portion. Thus, the outlet portions of adjacent diffuser air passages are communicated with each other.
JP 2003-328999 A (paragraphs 0024-0025, FIG. 1)

  In a configuration with a diffuser, the pressure at the outlet increases due to the direction change of the wind that occurs when the wind passing through the diffuser wind path facing the fan flows from the outlet of the wind path to the back side of the diffuser. It tends to be easy. In addition to this, in the configuration in which the exit portions of the diffuser air passages facing and adjacent to the fan are communicated with each other as in Patent Document 1, a part of the wind that flows into the back side of the diffuser is generated. The air flows into the outlet of the adjacent diffuser air passage through the gap, and the air flow is disturbed at the outlet of each diffuser air passage facing the fan. Loss). Moreover, as the passage of airflow at the outlet portion is suppressed due to the turbulence of the airflow at the outlet portion, the pressure at the outlet portion further increases and the pressure loss increases. For this reason, in the electric blower of patent document 1, it is disadvantageous to improve ventilation efficiency, and in connection with this, the vacuum cleaner carrying the electric blower of patent document 1 is in terms of improving suction work rate. It is disadvantageous.

  An object of the present invention is to provide an electric blower that can improve the blowing efficiency by improving the diffuser.

  In order to solve the above-mentioned problem, the present invention provides a first edge having a first edge and a second edge continuous to the downstream end of each stationary blade of the diffuser facing the fan. In close contact with the inner surface of the fitting cylinder portion of the fan cover fitted on the fan, and the second edge is brought into close contact with the inner surface of the corner portion formed between the stationary blade presser portion and the fitting cylinder portion of the fan cover, Outlet portions of each diffuser air channel facing and adjacent to the fan are partitioned by a downstream end portion of the stationary blade.

  In this invention, it can suppress that a part of wind which flows into the back side of a diffuser through the diffuser wind path facing the fan flows into the exit part of an adjacent diffuser wind path.

  According to the present invention, since the diffuser has the stationary blade that can suppress the turbulence of the airflow at the outlet portion of the diffuser air passage, the electric blower that can improve the blowing efficiency can be provided.

  An embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a perspective view showing the entire canister-type vacuum cleaner. The vacuum cleaner 1 includes a cleaner body 2 having wheels that can freely move on a floor surface, an electric blower 3, and dust collection as a filter. A bag 4, a dust suction hose 5, an extension pipe 6, a suction port body 7, and the like are provided.

  The vacuum cleaner main body 2 has a dust collection chamber lid 2a that can be opened and closed, for example, forming the upper surface of the front portion. Inside the vacuum cleaner body 2 is provided a dust collection chamber (not shown) that is directly opposite to the dust collection chamber lid 2a, and is located behind this dust collection chamber, in other words, based on the intake air flow. A blower chamber (not shown) is provided on the downstream side of the dust chamber. The cleaner body 2 has an exhaust port (not shown) that communicates the inside and outside of the blower chamber.

  A dust collection bag 4 is accommodated in the dust collection chamber so that it can be taken in and out, and an electric blower 3 is accommodated in the blower chamber. For example, a dust suction port 2b is provided substantially horizontally at the front end portion of the cleaner body 2, and one end portion of the dust suction hose 5 on the cleaner body side is detachably connected to the dust suction port 2b. The dust suction hose 5 and the extension pipe 6 form a suction pipe that communicates the dust collection chamber and the suction port body 7, and the dust suction hose 5 has a handle 5a with a hand operation switch at the other end. One end of a hard extension pipe 6 is detachably connected to the handle 5a, and a suction port body 7 is detachably connected to the other end of the extension pipe 6.

  The electric vacuum cleaner 1 configured as described above drives the electric blower 3 to suck in dust on the surface to be cleaned from the suction port body 7 with the blowing force of the electric blower 3, and passes through the extension pipe 6 and the dust suction hose 5. Then, the dust can be trapped by the dust collection bag 4 in the chamber. Then, the air (intake flow) that has passed through the dust bag 4 is sucked into the electric blower 3 and passes through the electric blower 3, and then discharged to the outside of the cleaner body 2 through an exhaust port (not shown) of the cleaner body 2. Is done. Thus, the surface to be cleaned can be cleaned.

  Next, the electric blower 3 will be described with reference to FIGS. As shown in FIG. 2, the electric blower 3 includes an electric motor case 10, a stator 11, a rotor 12, a pair of brush devices 13, a fan 14, a diffuser 15, a fan cover 16, and the like. The motor case 10, the stator 11, the rotor 12, and the pair of brush devices 13 form an electric motor part M composed of, for example, a commutator motor.

  As shown in FIG. 2, the sheet metal motor case 10 is formed by connecting a case body 21 and a case end face plate 22. The opening edge of the bottomed cylindrical case body 21 forms an annular projecting edge portion 21a projecting outward. A cylindrical bearing support portion 23 is formed at the center of the closed end plate portion 21 b of the case body 21, and a bearing 24 is accommodated in the bearing support portion 23. A plurality of exhaust ports 25 (only one is shown) are opened in the cylindrical peripheral wall of the case body 21.

  The case end face plate 22 crosses the opening of the case main body 21 in the radial direction, and both end portions thereof are fixed to the overhanging edge portion 21a with screws 26. A cylindrical bearing support portion 27 that protrudes outside the electric motor case 10 corresponding to the bearing support portion 23 is formed at the center portion in the longitudinal direction of the case end face plate 22, and a bearing 28 is accommodated therein. ing.

  The stator 11 includes a stator iron core having a substantially rectangular outer shape and a stator winding wound around the iron core. The stator 11 is accommodated in the electric motor case 10 with the four corners of the stator core pressed against the inner surface of the cylindrical peripheral wall of the case body 21. An in-case air passage 30 (only one is shown) is formed between the outer surface of the stator core of the accommodated stator 11 and the inner surface of the cylindrical peripheral wall facing the stator core.

  The rotor 12 has a commutator 31. The rotor 12 is rotatably mounted on the motor case 10 so as to be positioned inside the stator 11 by supporting the rotation shaft 12a on the bearings 24 and 28, respectively. The pair of brush devices 13 are attached so as to penetrate the case main body 21 in the radial direction, and the tips of the carbon brushes 13 a included in these devices 13 are pressed against the commutator 31.

  A fan portion F is formed by the fan 14, the diffuser 15, and the fan cover 16.

  Specifically, the rotary shaft 12 a passes through the bearing 28 and the bearing support portion 27 that accommodates the bearing 28, and the fan 14 is connected to the through end portion by a nut 32. The fan 14 is a centrifugal type, and is formed by connecting a disk-shaped base 35 and a front shroud 36 facing the base 35 by a plurality of centrifugal blades (only one is shown) 37. A discharge port 14 a is formed in the outer peripheral portion of the fan 14, and a suction port 38 is provided in the central portion of the front shroud 36.

  The diffuser 15 is disposed between the fan 14 and the motor case 10 so as to cover and conceal the portion of the case end face plate 22 excluding the bearing support portion 27 and the overhang edge portion 21a. The center portion of the diffuser 15 is fixed to the case end face plate 22 with a plurality of screws 39 (only one is shown), and the back surface of the peripheral portion is supported against the overhanging edge portion 21a. Reference numeral 15 a in FIG. 3 indicates a through hole of the screw 39.

  The diffuser 15 is an integrally molded product made of a synthetic resin, and introduces the airflow discharged from the fan 14 into the opening of the electric motor case 10 while reducing the static pressure. Specifically, as shown in FIG. 3 and the like, a substantially circular base 41, a large number of front-side stationary blades 42 integrally provided on the surface of the peripheral portion of the base 41, A plurality of stationary blades 45 on the back side provided integrally with the back surface.

  The stationary vanes 42 on the front side are provided at equal intervals along the circumferential direction of the base 41, and all have a substantially arc shape. A front-side diffuser air path P is formed between the adjacent stationary blades 42 as shown in FIG. The cross-sectional areas of these diffuser air paths P are formed to gradually increase from the inlet part P1 facing the discharge port 14a of the fan 14 to the outlet part P2 opened on the outer periphery of the diffuser 15.

  As representatively shown in FIG. 6, the edge of each stationary blade 42 is formed by first to third edges E <b> 1 to E <b> 3 and a fourth edge E <b> 4 that are continuous with each other. The first edge E <b> 1 extends from the outer peripheral surface of the base 41 so as to be substantially perpendicular to the surface of the base 41. The third edge E <b> 3 extends along the diffuser air path P, mainly includes an edge part parallel to the base 41, and has an oblique edge part gradually approaching the base 41 from this edge part. . The second edge E2 is formed by connecting an edge portion parallel to the base 41 of the third edge E3 and the first edge E1, and this edge is formed in accordance with the shape of a corner portion of the fan cover 16 which will be described later. Has been. Note that reference numerals G1 and G2 in FIG. 6 are boundary lines drawn for easy understanding, and one boundary line G1 indicates a boundary between the first edge E1 and the second edge E2, and the other boundary. A line G2 indicates a boundary between the second edge E2 and the third edge E3. The fourth edge E4 extends so as to be substantially perpendicular to the surface of the base 41 on the inlet portion P1 side, and is continuous with the oblique edge portion of the third edge E3.

  The downstream end 42a of each stationary blade 42 faces the outlet portion P2, and has a first edge E1 and a second edge E2. In order to facilitate understanding, in FIG. 3 and FIG. 6, the boundary between the downstream end portion 42 a and the upstream portion 42 b is indicated by a boundary line H. The plate thickness of the upstream portion 42b of each stationary blade 42 is the same for each portion. The plate | board thickness of the downstream edge part 42a of each stationary blade 42 is thinner than the plate | board thickness of the upstream part 42b, and it is thinner toward the 1st edge E1 side. The downstream end 42a is made elastically deformable by this change in thickness. In addition, the code | symbol 42c in FIG. 6 has shown the plane part formed in the front-end | tip outer surface of the downstream end part 42a.

  The respective stationary vanes 45 on the back side provided at equal intervals along the circumferential direction of the base 41 have a substantially arc shape and extend from the outer periphery of the base 41 to the center of the base 41. A diffuser air passage PB on the back side is formed between the adjacent stationary blades 45. The air passage cross-sectional areas of these diffuser air passages PB are larger than the air passage cross-sectional area of the front-side diffuser air passage P, and are gradually increased from the outer periphery of the base 41 toward the center of the base 41. As shown in FIGS. 4 to 6, the diffuser air paths P and PB on the front side and the back side are communicated with each other through a notch-shaped communication recess 41 a provided at equal intervals on the outer periphery of the base 41.

  As shown in FIGS. 2 to 4, the fan cover 16 includes a fan facing portion 51, a fitting cylinder portion 52, and a stationary blade pressing portion 53, and is formed of, for example, a sheet metal. The fan facing portion 51 is a portion facing the front shroud 36 in the vicinity thereof, and an air inlet 16a facing the air inlet 38 is opened at the center thereof.

  The fitting cylinder part 52 is a part fitted to the overhanging edge part 21 a and the diffuser 15. The inner diameter of the fitting cylinder portion 52 is substantially equal to the outer diameter of the diffuser 15, and in the case of this embodiment, the downstream end 42 a of each stationary blade 42 can be elastically deformed with the fitting to the diffuser 15. The outer diameter of the diffuser 15 is made larger than the inner diameter of the fitting cylinder part 52 so that it can do. The same number of exhaust holes 54 as the diffuser air passages P are formed in the fitting cylinder portion 52 at regular intervals along the circumferential direction.

  The stationary blade pressing portion 53 is a portion that presses each stationary blade 42 by continuously connecting the fan facing portion 51 and the fitting cylinder portion 52 together. A corner portion 16 b of the fan cover 16 is formed by the stationary blade pressing portion 53 and the fitting cylinder portion 52. The corner portion 16 b is continuous in the circumferential direction of the fan cover 16. The corner portion 16b is curved and rounded in, for example, a cross section. Instead, the corner portion 16b is formed in an oblique shape, and the angle formed by the fan facing portion 51 and the fitting cylinder portion 52 is an obtuse angle. It can also be formed.

  After the diffuser 15 is screwed to the motor part M and the fan 14 disposed thereon is attached to the rotary shaft 12a, the fan cover 16 is fitted to the motor part M and the fan part F is assembled. . At this time, the fan cover 16 is fitted on the overhanging edge portion 21a and the diffuser 15 while rotating in the arrow direction in FIG.

  With the operation of fitting the fan cover 16, the downstream end 42 a of each stationary blade 42 is elastically deformed, and the first edge E 1 and the flat portion 42 c are elastic on the inner peripheral surface of the fitting cylinder portion 52. Closely. Similarly, due to the elastic deformation of each downstream end 42a, the second edge E2 of each downstream end 42a is elastically brought into close contact with the inner surface of the corner 16b of the fan cover 16 at the final stage of the fitting operation. However, the edge portion parallel to the base 41 at the third edge E3 of each stationary blade 42 is in close contact with the inner surface of the stationary blade pressing portion 53 of the fan cover 16. Then, maintaining this close contact, the peripheral portion of the diffuser 15 is strongly sandwiched between the overhanging edge portion 21 a and the stationary blade pressing portion 53. The fitted state of the fan cover 16 resisting the elastic repulsive force of each downstream end 42 a is maintained by the friction of the fitting portion of each fan cover 16 with the fitting edge portion 21 a and the diffuser 15. Is done. In addition, a part of the fitting tube portion 52 may be deformed by a punch from the outside, and the deformed portion may bite into the peripheral surface of the base 41 of the diffuser 15.

  In the fan portion F assembled as described above, the third edge E3 of each stationary blade 42 is not only in close contact with the inner surface of the stationary blade pressing portion 53 of the fan cover 16, but the first, The second edges E1 and E2 are continuously in close contact with the inner surface of the fitting tube portion 52 of the fan cover 16 and the inner surface of the corner portion 16b extending from the fitting tube portion 52 to the stationary blade presser portion 53. Thereby, the clearance gap which connects the exit part P2 of the adjacent diffuser wind path P between the downstream edge part 42a of each stationary blade 42, the inner surface of the fitting cylinder part 52, and the inner surface of the corner part 16b is carried out. The formation is suppressed, and the adjacent diffuser air paths P are separated and independent from each other without using a sealing material.

  Moreover, in order to bring the first and second edges E1 and E2 of the downstream end 42a of each stationary blade 42 into close contact with the inner surface of the fitting tube portion 52 and the inner surface of the corner portion 16b, the downstream end portion 42a is formed. It is realized by elastic deformation. Thereby, not only a sealing material that requires high costs for close contact is required, but also excellent close compatibility with the shape of the corner portion 16b is excellent.

  With the above configuration, as the fan 14 rotates, it passes through the front diffuser air passage P facing the fan 14 and then changes direction at the communication recess 41a to flow into the rear diffuser air passage PB. It is possible to suppress a part of the wind flowing into the outlet portion P2 of the adjacent diffuser air passage P. Accordingly, since the turbulence of the air flow at the outlet portion P2 of each diffuser air passage P is suppressed, the air passage loss (wind loss) caused by the vortex flow at the outlet portion P2 can be suppressed, and the front side diffuser can be suppressed. Since the wind passing through the air passage P is smoothly introduced into the diffuser air passage PB on the back side through the communication recess 41a, the air blowing efficiency of the electric blower 3 can be improved.

  4 and 5 show the positional relationship between the diffuser 15 and the exhaust hole 54 when the fan part F is assembled. That is, the same number of exhaust holes 54 as the number of the diffuser air paths P on the front side are provided so that a part thereof faces the outlet P2 of the diffuser air path P. In the present embodiment, the exhaust hole 54 does not face the diffuser air path PB on the back side. Each exhaust hole 54 may be provided so as to face the outlet P2 of the diffuser air passage P as a whole.

  Due to the exhaust holes 54 arranged in this way, a part of the wind guided by each diffuser air path P can be smoothly passed through the exhaust holes 54 to the outside of the fan cover 16 without significant change in direction at the outlet P2. Can be discharged. Since this exhaust can suppress an increase in pressure at the outlet portion P2 of each diffuser air path P, it is possible to suppress a decrease in blowing efficiency due to pressure loss.

  Therefore, in the electric blower 3 having the above-described configuration, it is possible to suppress a decrease in the blowing efficiency due to the windage loss and the pressure loss at the outlet portion P2 of each diffuser air passage P. Therefore, the blowing efficiency of the electric blower 3 is improved and the air volume is increased. As a result, the suction power of the vacuum cleaner 1 can be improved.

  The present invention is not limited to the one embodiment. For example, the present invention can be applied to an electric blower in which the electric motor portion is not provided with an overhanging edge and the fan cover is fitted and attached only to the diffuser, and the electric motor portion is not limited to a commutator electric motor but is a brushless motor. May be. Further, in the present invention, when the downstream end portion 42a of the stationary blade 42 is not made elastic, an elastic sealing material is attached to the inner surfaces of the fitting cylinder portion 52 and the corner portion 16b, so that they are attached thereto. It is also possible to keep the air tightness by bringing the first and second edges E1 and E2 of the downstream end portion 42a into close contact with each other. The airtightness between the third edge E3 of the stationary blade 42 and the stationary blade pressing portion 53 can also be performed with a sealing material interposed.

The perspective view which shows the vacuum cleaner carrying the electric blower which concerns on one Embodiment of this invention. 1 is a side view showing a part of an electric blower according to an embodiment of the present invention. The perspective view which shows the fan cover and diffuser with which the electric blower of FIG. 2 is provided. The expanded sectional view of the Z section in FIG. Sectional drawing which follows the YY line in FIG. The perspective view which expands and shows a part of diffuser with which the electric blower of FIG. 2 is provided.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 3 ... Electric blower, M ... Electric motor part, F ... Fan part, 12a ... Rotating shaft, 14 ... Fan, 14a ... Discharge port, 15 ... Diffuser, 16 ... Fan cover, 16b ... Corner part, 36 ... Front shroud 41 ... Base, 41a ... Communication recess, 42 ... Stator blade, 42a ... Downstream edge of the stator blade, P ... Diffuser air passage, P1 ... Inlet portion, P2 ... Outlet portion, E1 ... First edge, E2 ... second edge, E3 ... third edge, 51 ... fan facing part, 52 ... fitting cylinder part, 53 ... static blade pressing part, 54 ... exhaust hole

Claims (3)

A fan connected to the rotating shaft of the electric motor unit and a fan cover covering the fan; and a plurality of stationary blades disposed around the fan so as to face the discharge port of the fan. In the electric blower in which the diffuser for guiding the wind discharged from the fan in the diffuser air passage between the stationary blades is disposed between the electric motor unit and the fan,
The fan cover is provided with a fan facing portion facing the front shroud of the fan, a fitting cylinder portion fitted on the outer periphery of the diffuser, and the fan facing portion and the fitting cylinder portion continuously provided. And having a stationary blade presser portion for pressing the stationary blade,
The downstream end of the stationary blade is formed over a first edge that is in close contact with the inner surface of the fitting tube portion, and the fitting tube portion and the stationary blade presser portion that are continuous with the first edge. An electric blower having a second edge that is in close contact with the inner surface of the corner portion of the fan cover and partitioning the outlet portions of the adjacent diffuser air passages at the downstream end of the stationary blade.   2. The electric blower according to claim 1, wherein a diameter of the diffuser passing through the first edge is larger than an inner diameter of the fitting tube portion, and a downstream end portion of the stationary blade is formed to be elastically deformable. Yes.   3. The electric blower according to claim 1, wherein an exhaust hole at least partially facing an outlet portion of the diffuser air passage is provided in the fitting cylinder portion for each of the diffuser air passages.

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