JP2010038027A - Electric blower and electric vacuum cleaner using the same - Google Patents

Abstract

An electric blower that prevents or reduces a circulating flow generated in the vicinity of a front shroud and has high blowing efficiency and a vacuum cleaner using the same.
A fan case spacer (35) integrally molded with a fan case (34) is sealed against a suction port (30) side of a front shroud (27) to prevent circulation flow from an exhaust port (37) of an impeller (25) back to the intake port (30). At the same time, by narrowing the gap g between the exhaust port 37 side of the front shroud 27 and the fan case spacer 35, it is possible to improve the blowing efficiency by reducing the circulation flow generated in the vicinity of the exhaust port 37.
[Selection] Figure 4

Description

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

  Conventionally, as this type of electric blower, as shown in FIGS. 10 and 11, an impeller 4 having a front shroud 1, a rear shroud 2, and a blade 3, an air guide 5 and an intake port 6 around the impeller 4 are provided. A fan case 7 including the impeller 4 and the air guide 5, and a motor unit (not shown), the front shroud 1 end of the impeller 4 on the intake port 8 side or the exhaust port 9 side, and the fan case 7 Between the exhaust port 9 of the impeller 4 through the upper side of the front shroud 1 and reducing the circulating flow A flowing to the intake port of the impeller 4 (for example, patents). Reference 1).

  Further, as shown in FIG. 12, the fan case 7 is provided with a fixing portion 10 that fills a gap between the end portion of the front shroud 1 on the exhaust port 9 side and the end portion of the air guide 5, and the exhaust port 9 of the front shroud 1 is provided. In some cases, the air flow efficiency from the exhaust port 9 of the impeller 4 to the intake port of the impeller 4 is reduced by making the side end portion and the fixing portion 10 slightly contact each other, thereby improving the blowing efficiency. (For example, refer to Patent Document 2).

Further, as shown in FIG. 13, a cap 11 is formed integrally with the fan case 7 at the air inlet 6 of the fan case 7 and the air inlet 8 side of the front shroud 1 is brought into contact with the cap 11 so that the circulation flow A Some prevent the occurrence of (see, for example, Patent Document 3).
Japanese Patent Laid-Open No. 60-216097 JP-A-6-307391 JP-A-6-323297

  However, in the conventional configuration shown in FIGS. 10 and 11, the fan case 7 is generally made of metal from the viewpoint of heat resistance and soundproofing. In addition, since the gap remains between the front shroud 1 of the impeller 4 and the fan case 7, the circulation flow arrow A cannot be completely prevented. Had no problem.

  In the conventional configuration shown in FIG. 12, the fixing portion 10 is provided in the vicinity of the exhaust port 9 of the front shroud 1, but the vicinity of the exhaust port 9 having a large diameter is shaken by the rotation of the impeller 4 (the arrow B is large). In addition, it is difficult to maintain the sealing performance, and there is a problem that the friction loss at the contact portion between the front shroud 1 and the fixing portion 10 is large.

  Further, the conventional configuration shown in FIG. 13 has a problem that the air blowing efficiency is lowered by the circulating flow C caused by the gap between the fan case 7 and the exhaust port 9 side of the front shroud 1 of the impeller 4. It was.

  The present invention solves the above-described conventional problems, and provides an electric blower that prevents circulation flow generated in the vicinity of a front shroud in a fan case and improves blowing efficiency, and an electric vacuum cleaner using the electric blower. Objective.

  In order to solve the above-described conventional problems, an electric blower of the present invention and a vacuum cleaner using the electric blower have a fan case spacer integrally formed with the fan case, and the fan case spacer is brought into contact only with the intake port of the impeller. The gap between the outer peripheral end of the front shroud and the fan case spacer is narrowed.

  As a result, the air inlet side of the front shroud, which is less likely to shake due to the rotation of the impeller and is easy to maintain a seal, is sealed, and the gap between the exhaust shroud side end of the front shroud and the fan case is separated from the inclined portion of the front shroud By making it narrower than the gap between the case spacer, the circulating flow from the impeller exhaust port to the impeller intake port through the upper side of the front shroud is prevented, and the circulating flow near the exhaust port of the front shroud is further prevented. Therefore, it is possible to improve the air blowing efficiency.

  Further, by integrally molding the fan case spacer with the fan case, the above effects can be obtained with a simple configuration. At this time, since the contact portion between the fan case and the fan case spacer can be widened, it is possible to prevent the fan case spacer from being detached from the fan case. Furthermore, by making the fan case spacer a resin part, it is possible to facilitate processing even if it has a complicated shape.

  Moreover, the vacuum cleaner using this electric blower is extremely practical with high blowing efficiency and strong suction force.

  The electric blower of the present invention and the electric vacuum cleaner using the electric blower can improve the blowing efficiency by reducing or preventing the circulation flow generated in the vicinity of the front shroud in the fan case.

  According to a first aspect of the present invention, there is provided an impeller that is rotationally driven by an electric motor, an air guide having a plurality of tongs disposed around the impeller, a fan case that has an air inlet in the center and encloses the impeller and the air guide. The impeller includes a front shroud having an air inlet and an inclined portion, a rear shroud spaced apart from the front shroud, and a blade sandwiched by the pair of shrouds, and the fan A fan case spacer that covers from the air inlet of the impeller to the top of the impeller side tip of the air guide is formed integrally with the fan case on the inner surface of the impeller, and the fan case spacer is connected to the front shroud only at the air inlet of the impeller. The gap between the outer peripheral end of the front shroud of the impeller and the fan case spacer. The front shroud is configured to be narrower than the gap between the inclined portion of the loudspeaker and the fan case spacer, so that the fan's rotation radius is small, so there is less blur due to the rotation of the fan, and the sealing performance is easy to maintain. The air inlet side of the fan has a contact-type seal structure, and the fan shroud causes a large amount of vibration due to the rotation of the fan. Is made narrower than the gap between the inclined part of the front shroud and the fan case spacer, thereby preventing the circulation flow from the exhaust port of the impeller through the upper side of the front shroud to the intake port of the impeller. Since the circulation flow in the vicinity of the exhaust port can be reduced, the air blowing efficiency can be improved.

  In a second aspect of the invention, in particular, in the first aspect of the invention, the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide is parallel from the impeller side tip position of the air guide to be substantially parallel to the rotation axis direction of the impeller. By forming the portion, the front shroud and the fan case spacer do not come into contact with each other even if the impeller is shaken in the axial direction. Therefore, it is possible to prevent friction loss caused by the front shroud coming into contact with the fan case spacer.

  According to a third aspect of the invention, in particular, in the first aspect of the invention, the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide is substantially changed from the position inside the impeller side tip position of the air guide to the rotation axis direction of the impeller. By forming the parallel portion that is parallel, the fan case spacer can reliably cover the impeller side tip portion of the air guide, so that it is possible to prevent leakage flow loss flowing through the gap between the air guide flow paths. .

  According to a fourth aspect of the present invention, in particular, in any one of the first to third aspects, the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide is an inclined portion that is inclined with respect to the rotation axis direction of the impeller. By forming so as to have the airflow from the impeller exhaust port, the airflow can be reduced in the gap between the front shroud and the fan case.

  In a fifth aspect of the invention, in particular, in any one of the first to fourth aspects of the invention, the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide is formed so as to have a fillet in which the impeller direction is convex. As a result, not only can the airflow from the impeller exhaust port be guided in the direction of the air guide, but also the gap between the front shroud and the fan case spacer can be reduced, so the airflow in the gap between the front shroud and the fan case Can be reduced.

  In a sixth aspect of the invention, in particular, in any one of the first to fourth aspects of the invention, the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide is formed so as to have a fillet in which the impeller direction is concave. Thus, even if the impeller is shaken in a direction twisting with respect to the shaft, the front shroud and the fan case spacer do not come into contact with each other, so that friction loss caused by the front shroud coming into contact with the fan case spacer can be prevented.

  The seventh aspect of the invention is an extremely practical electric vacuum cleaner that has a high blowing efficiency and a strong suction force, in particular by using the electric vacuum cleaner having the electric blower according to any one of the first to sixth aspects of the invention. Obtainable.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 to 5 show an electric blower according to Embodiment 1 of the present invention.

  As shown in FIGS. 1 to 3, an electric motor 22 is disposed in the electric blower 21 in the present embodiment. The electric motor 22 is covered by a bracket 23 and connected to an impeller 25 by a rotating shaft 24. The impeller 25 is sandwiched between a sheet metal front shroud 27 having an inclined portion 26, a sheet metal rear shroud 28 spaced apart from the front shroud 27, and a pair of front shroud 27 and rear shroud 28. A plurality of sheet metal blades 29 and a resin inducer 31 provided corresponding to the air inlet 30 provided in the center of the front shroud 27.

  Around the impeller 25, an air guide 33 whose flow path is divided by a plurality of tongs 32 is arranged, and the impeller 25 and the air guide 33 are enclosed by a metal fan case 34. A resin fan case spacer 35 is molded integrally with the fan case 34.

  Details around the impeller 25 will be described with reference to FIG.

  As shown in FIG. 4, in the vicinity of the air inlet 36 of the fan case 34, the air inlet 30 side of the front shroud 27 and the fan case spacer 35 are abutted and sealed to prevent the circulation flow D from occurring. . Further, in order to reduce the circulation flow F generated by the gap between the discharge port 37 of the impeller 25 and the fan case 34, the fan case spacer 35 is substantially parallel to the rotary shaft 24 from the tip position 38 on the impeller 25 side of the air guide 33. The parallel part 35a which becomes is provided.

  About the electric blower comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, when the electric blower 21 is activated, the electric motor 22 rotates, and the rotating shaft 24 and the impeller 25 rotate accordingly. As a result, air is sucked from the intake port 30 of the impeller 25 and discharged from the exhaust port 37. Most of the air exhausted from the exhaust port 37 of the impeller 25 flows into the flow path of the air guide 33 divided by the tongs 32, and pressure recovery is performed by the diffuser effect.

  At this time, a part of the air discharged from the discharge port 37 of the impeller 25 passes through the gap between the front shroud 27 and the fan case 34, and a circulating flow D flows again into the intake port 30 of the impeller 25. . Since the flow of the circulating flow D does not perform the work of blowing, the blowing efficiency is lowered.

  However, in this embodiment, since the air inlet 30 side of the front shroud 27 and the fan case spacer 35 are in contact with each other, the air flow efficiency is improved by preventing the circulation flow D. In particular, according to the present invention, the front shroud 27 having a small diameter is sealed on the intake port 30 side, so that the amount of blurring due to the rotation of the impeller 25 is small, it is easy to maintain the sealing performance, and the front surface having a large diameter. Since the amount of blurring due to the rotation of the impeller 25 is large on the exhaust port 37 side of the shroud 27, a combination of non-contact type seal structures in which a gap g is provided between the end of the exhaust port 37 of the front shroud 27 and the fan case spacer 35 is used. Therefore, it has the feature of improving the sealing performance.

  Further, when the gap g between the discharge port 37 side of the front shroud 27 and the fan case 34 is large, circulation in which air enters and exits the gap e between the inclined portion 26 of the front shroud 27 and the fan case 34. Stream F is generated. Since the flow of the circulating flow F also does not perform the air blowing work, the air blowing efficiency is lowered. If the gap e between the inclined portion 26 of the front shroud 27 and the fan case 33 is narrowed in order to reduce the circulating flow F, the friction loss due to the viscosity of the air may increase, and the blowing efficiency may decrease. There is.

  However, in the present embodiment, the fan case spacer 35 is provided up to the vicinity of the tip position 38 on the impeller 25 side of the air guide 33, thereby reducing the gap g between the discharge port 37 side of the front shroud 27 and the fan case 34. Therefore, it is set as the structure which improves ventilation efficiency by reducing the circulation flow arrow F, without increasing the friction loss by the viscosity of air.

Here, in the present embodiment, the fan case spacer 35 is provided with a parallel portion 35a that is substantially parallel to the rotation shaft 24 from the tip position 38 on the impeller 25 side of the air guide 33. Even when the front shaft shroud 27 strikes the fan case spacer 35 even when it shakes in the direction of twisting with respect to the rotating shaft 24, it can be prevented that friction loss occurs. This is because, particularly when it is difficult to ensure the rigidity of the front shroud 27 or when the impeller 25 has a high rotational speed, the front shroud 27 is caused to move in the radial direction by centrifugal force during rotation of the impeller 25. Even when the front shroud 27 is deformed
Is effective because it does not hit the fan case spacer 35.

  Here, if it is known that the impeller 25 is not greatly shaken in the direction of the rotating shaft 24 or twisted with respect to the rotating shaft 24, the fan case spacer 41 is moved to the tip of the impeller 25 side of the air guide 33 as shown in FIG. It is better to form the parallel part 35b which becomes substantially parallel to the rotating shaft 24 from the inside from the position 38. As a result, the fan case spacer 41 can be surely covered up to the front end of the tongue 32 of the air guide 33, so that the air enters and exits between the flow paths at the upper end of the front end of the air guide 33 indicated by the arrow H in FIG. Since the leakage loss due to the air can be reduced, the air blowing efficiency can be improved.

  In the present embodiment, since the fan case spacer 35 is made of resin and the front shroud 27 is made of sheet metal, even if the front shroud 27 hits the fan case spacer 35, the fan case spacer 35 having low strength is used. Therefore, the device can be used safely without being damaged.

  Further, by integrally molding the fan case spacer 35 with the fan case 34, a complicated attachment method is not required, and an effect of improving the blowing efficiency can be obtained with a simple configuration. Further, since the contact portion between the fan case 34 and the fan case spacer 35 can be widened, the fan case spacer 35 can be prevented from being detached from the fan case 34. Further, since the fan case spacer 35 is made of resin, it can be easily processed even if it has a complicated shape.

  As described above, in the present embodiment, the fan case spacer 35 can reduce or prevent the circulation flow generated in the vicinity of the front shroud 27, so that the air blowing efficiency can be improved.

(Embodiment 2)
FIG. 6 is a detailed configuration diagram around the impeller 25 of the electric blower according to the second embodiment of the present invention.

  The present embodiment is different from the first embodiment in that the fan case spacer 51 is provided with an inclined portion 52 at an angle I with respect to the rotation shaft 24 direction from the tip position 38 of the impeller 25 side tongue 32 of the air guide 33. This is the point. Others are the same as those of the first embodiment, and the same numbers are assigned and detailed description is omitted.

  With the rotation of the impeller 25, a part of the air exhausted from the exhaust port 37 flows in a direction spreading from the exhaust port 37, becomes a circulation flow as described above, and lowers the blowing efficiency. However, in the present embodiment, since the fan case spacer 51 is provided with the inclined portion 52, the air flow is guided to the air guide 33 by the inclined portion 52 as shown by the air flow J. It is possible to reduce the air blowing efficiency.

(Embodiment 3)
FIG. 7 is a detailed configuration diagram around the impeller 25 of the electric blower according to the third embodiment of the present invention.

  The present embodiment differs from the first embodiment in that the fan case spacer 61 is provided with a fillet portion 62 in the vicinity of the tip position 38 of the impeller 25 side tongue 32 of the air guide 33 so that the direction of the impeller 25 is convex. It is a point. Others are the same as those of the first embodiment, and the same numbers are assigned and detailed description is omitted.

  As described above, along with the rotation of the impeller 25, a part of the air exhausted from the exhaust port 37 flows in a direction spreading from the exhaust port 37 and becomes a circulating flow as described above, thereby reducing the blowing efficiency. However, in this embodiment, since the fillet portion 62 is provided in the fan case spacer 51, the air flow is guided to the air guide 33 by the fillet portion 62 as shown by the air flow k. It is possible to reduce the air blowing efficiency. Furthermore, since the distance l between the exhaust port 37 side of the front shroud 27 and the fan case spacer 61 can be reduced as compared with the case where the inclined portion 52 is provided as in the second embodiment, further circulation. Since the flow reduction effect can be obtained, the blowing efficiency can be further increased.

(Embodiment 4)
FIG. 8 is a detailed configuration diagram around the impeller 25 of the electric blower according to the fourth embodiment of the present invention.

  This embodiment is different from the first embodiment in that the fan case spacer 71 is provided with a fillet portion 72 in the vicinity of the tip position 38 of the impeller 25 side tongue 32 of the air guide 33 so that the direction of the impeller 25 is concave. It is a point. Others are the same as those of the first embodiment, and the same numbers are assigned and detailed description is omitted.

  When the impeller 25 is rotated, the front shroud 27 hits the fan case spacer 71 when it is greatly shaken in the direction of the rotating shaft 24 or the direction of twisting with respect to the rotating shaft 24, and friction loss occurs. Since the fillet portion 72 is provided in the fan case spacer 71 so that the direction of the impeller 25 is concave, the front shroud 27 can be prevented from hitting the fan case spacer 71. This is because, particularly when it is difficult to ensure the rigidity of the front shroud 27 or when the impeller 25 has a high rotational speed, the front shroud 27 is caused to move in the radial direction by centrifugal force during rotation of the impeller 25. Even in the case of deformation, the front shroud 27 does not hit the fan case spacer 71, which is effective.

(Embodiment 5)
FIG. 9 shows a vacuum cleaner according to Embodiment 5 of the present invention.

  In FIG. 9, the vacuum cleaner 81 has a hose 82, an extension pipe 83, and a suction tool 84 that moves on the floor surface to suck dust, and the vacuum cleaner main body 85 includes the first to fourth embodiments. The electric blower 21 having the fan case spacer (not shown) shown in FIG.

  About the vacuum cleaner comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, when the vacuum cleaner 21 is activated, the electric blower 21 blows air. Since the fan case spacer (not shown) shown in Embodiments 1 to 4 is provided inside the electric blower 21, the electric blower 21 operates with high blowing efficiency. Therefore, the vacuum cleaner as a whole can operate with high blowing efficiency, can obtain a strong suction force, and is extremely practical.

  As described above, the electric blower according to the present invention and the electric vacuum cleaner using the electric blower can prevent or reduce the circulation flow generated in the vicinity of the front shroud by the fan case spacer, thereby improving the blowing efficiency. Therefore, it can be applied not only to home use but also to business equipment.

Front view of electric blower in Embodiment 1 of the present invention The perspective view which shows the structure of the impeller of the electric blower Perspective view of the air guide of the electric blower Sectional drawing which shows the detailed structure of the impeller periphery of the electric blower Sectional drawing which shows the detailed structure of the impeller periphery of another form of the electric blower Sectional drawing which shows the detailed structure of the impeller periphery of the electric blower in Embodiment 2 of this invention Sectional drawing which shows the detailed structure of the impeller periphery of the electric blower in Embodiment 3 of this invention Sectional drawing which shows the detailed structure of the impeller periphery of the electric blower in Embodiment 4 of this invention Whole structure figure of the vacuum cleaner in Embodiment 5 of this invention Sectional drawing which shows the detailed structure of the impeller periphery of the conventional electric blower Sectional drawing which shows the detailed structure of the impeller periphery of another form of the electric blower Sectional drawing which shows the detailed structure of the impeller periphery of another form of the electric blower Sectional drawing which shows the detailed structure of the impeller periphery of another form of the electric blower

Explanation of symbols

DESCRIPTION OF SYMBOLS 21 Electric blower 22 Electric motor 24 Rotating shaft 25 Impeller 27 Front shroud 28 Rear shroud 29 Blade 30 Inlet 32 Tong 33 Air guide 34 Fan case 35, 41, 51, 61, 71 Fan case spacer 35a Parallel part 35b Parallel part 52 Inclined part 62, 72 Fillet part 81 Vacuum cleaner

Claims (7)

An impeller that is rotationally driven by an electric motor; an air guide having a plurality of tongs disposed around the impeller; and a fan case that includes an air inlet in the center and encloses the impeller and the air guide; Includes a front shroud having an air inlet and an inclined portion, a rear shroud disposed at a distance from the front shroud, and a blade sandwiched between the pair of shrouds, and the impeller is disposed on the inner surface of the fan case. A fan case spacer that covers from the air inlet to the top of the impeller side tip of the air guide is formed integrally with the fan case, and the fan case spacer contacts the front shroud only at the air inlet of the impeller, Inclination of the front shroud through the gap between the outer edge of the front shroud and the fan case spacer An electric blower that configured to be narrower than the gap between the fan case spacer and. 2. The electric blower according to claim 1, wherein the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide forms a parallel portion that is substantially parallel to the impeller rotation axis direction from the impeller side tip position of the air guide. The shape of the fan case spacer in the vicinity of the impeller side tip of the air guide forms a parallel portion that is substantially parallel to the rotation axis direction of the impeller from a position inside the impeller side tip position of the air guide. Electric blower. 4. The electric blower according to claim 1, wherein the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide is formed so as to have an inclined portion that is inclined with respect to the rotation axis direction of the impeller. 5. The electric blower according to any one of claims 1 to 4, wherein the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide is formed so as to have a fillet in which the impeller direction is convex. The electric blower according to any one of claims 1 to 4, wherein the shape of the fan case spacer in the vicinity of the impeller side tip of the air guide is formed to have a fillet in which the impeller direction is concave. The vacuum cleaner which has an electric blower of any one of Claims 1-6.

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