EP3327294A1

EP3327294A1 - Blower device and cleaner

Info

Publication number: EP3327294A1
Application number: EP16907284.0A
Authority: EP
Inventors: Tomoyoshi Sawada; Machiko Fukushima; Haruki Yoshimatsu
Original assignee: Nidec Corp
Current assignee: Nidec Corp
Priority date: 2016-06-30
Filing date: 2016-06-30
Publication date: 2018-05-30
Also published as: JPWO2018003051A1; CN107850086A; WO2018003051A1; EP3327294A4; US20180209442A1

Abstract

A blower device that is installed in a cleaner includes an impeller that is rotatable around a rotary shaft as a center, the rotary shaft extending in an up-down direction; a motor that rotationally drives the impeller; a motor housing that accommodates the motor therein; a cylindrical member that is disposed outwardly of the motor housing in a radial direction; and an impeller case that accommodates the impeller. A gap is formed between an outer side surface of the motor housing and an inner side surface of the cylindrical member. A plurality of stationary blades are provided on one of side surfaces, that is, one of the outer side surface of the motor housing and the inner side surface of the cylindrical member, the plurality of stationary blades protruding towards the other side surface. At an outer portion of the motor housing in the radial direction, the plurality of stationary blades are disposed side by side in a circumferential direction, and form a plurality of air-current paths. At least one of the plurality of stationary blades includes a protrusion. The protrusion protrudes from a surface of the at least one of the plurality of stationary blades facing the radial direction and contacts the other side surface.

Description

Technical Field

The present invention relates to a blower device.

Background Art

Hitherto, blower devices including a plurality of stationary blades have been known, and have been installed in, for example, cleaners. For example, an electric blower in Japanese Unexamined Patent Application Publication No. 2012-67615 includes a motor portion, a centrifugal fan, diffusers, and a fan case. The centrifugal fan is rotationally driven by the motor portion. The diffusers include a plurality of stationary blades disposed around the centrifugal fan. The fan case has an intake port, and covers the diffusers. In order to narrow a gap between the stationary blades and the fan case, the fan case has protrusions.

Citation List

Patent Literature

PTL 1: Japanese Unexamined Patent Application Publication No. 2012-67615

Summary of Invention

Technical Problem

However, in the electric blower in Japanese Unexamined Patent Application Publication No. 2012-67615 , since a gap is formed between the protrusions and end portions of the stationary blades, the blowing efficiency of air currents that flow between the stationary blades is reduced. In particular, when resin components are to be connected to each other, it is difficult to bring the protruding portions and the end portions of the stationary blades into contact with each other due to, for example, assembly errors and dimensional errors of members.
In view of the above-described circumstances, it is an object of the present invention to effectively suppress a reduction in the blowing efficiency of air currents. Solution to Problem
An exemplary blower device according to the present invention includes an impeller that is rotatable around a rotary shaft as a center, the rotary shaft extending in an up-down direction; a motor that rotationally drives the impeller; a motor housing that accommodates the motor therein; a cylindrical member that is disposed outwardly of the motor housing in a radial direction; and an impeller case that accommodates the impeller. A gap is formed between an outer side surface of the motor housing and an inner side surface of the cylindrical member. A plurality of stationary blades are provided on one of side surfaces, that is, one of the outer side surface of the motor housing and the inner side surface of the cylindrical member, the plurality of stationary blades protruding towards the other side surface. At an outer portion of the motor housing in the radial direction, the plurality of stationary blades are disposed side by side in a circumferential direction, and form a plurality of air-current paths. At least one of the plurality of stationary blades includes a protrusion. The protrusion protrudes from an outwardly facing surface of the at least one of the plurality of stationary blades in the radial direction and contacts the other side surface.
An exemplary cleaner according to the present invention has the above-described blower device installed therein. Advantageous Effects of Invention
According to the exemplary blower device according to the present invention, it is possible to effectively suppress a reduction in the blowing efficiency of air currents. In addition, it is possible to provide a cleaner including such a blower device.

Brief Description of Drawings

[Fig. 1] Fig. 1 is a schematic vertical sectional view of a structural example of a blower device.
[Fig. 2A] Fig. 2A is a top perspective view of an external housing.
[Fig. 2B] Fig. 2B is a top view of the external housing.
[Fig. 2C] Fig. 2C is a bottom perspective view of the external housing.
[Fig. 3] Fig. 3 is a local enlarged view of a structural example of a gap between a motor and the external housing.
[Fig. 4] Fig. 4 is a top perspective view of an upper housing.
[Fig. 5] Fig. 5 is a top view of the upper housing.
[Fig. 6] Fig. 6 is a side view of the upper housing.
[Fig. 7] Fig. 7 is a bottom perspective view of the upper housing.
[Fig. 8] Fig. 8 is a bottom view of the upper housing.
[Fig. 9] Fig. 9 is a local enlarged view of a structural example of a stationary blade including a protruding portion.
[Fig. 10] Fig. 10 is a sectional view as seen from an axial direction of a stationary blade before the upper housing is fitted to the external housing.
[Fig. 11] Fig. 11 is a sectional view as seen from the axial direction of the stationary blade after the upper housing has been fitted to the external housing.
[Fig. 12] Fig. 12 is a local enlarged view of another structural example of a stationary blade including a protruding portion.
[Fig. 13] Fig. 13 illustrates an example of a cleaner having the blower device installed therein.

Description of Embodiments

An exemplary embodiment of the present invention is hereunder described with reference to the drawings. In the description, with regard to a motor 2 of a blower device 100, a direction of extension of a rotary shaft of a rotor 21 (refer to a shaft 211 in Fig. 1) is simply called "axial direction". Further, in the axial direction, a direction from a circuit board 6 towards an impeller 1 is simply called "upward", and a direction from the impeller 1 towards the circuit board 6 is simply called "downward". A surface of each structural element that faces upward in the axial direction is simply called "upper surface", and a surface of each structural element that faces downward in the axial direction is simply called "lower surface".
In the description, a radial direction with the axial direction as a center is simply called "radial direction", and a circumferential direction with the axial direction as a center is simply called "circumferential direction". Further, in the radial direction, a direction towards the rotary shaft is simply called "inward", and a direction away from the rotary shaft is simply called "outward". Further, regarding surfaces of each structural element, a side surface of each structural element that faces inward in the radial direction is simply called "inner side surface", and a side surface of each structural element that faces outward in the radial direction is simply called "outer side surface".
Regarding devices or apparatuses including the motor 2, in the description, a direction in which air current F that is sent out by the blower device 100 flows is called "blowing direction". In the blowing direction, a direction from an upstream side towards a downstream side is simply called "forward", and a direction from the downstream side towards the upstream side is simply called "backward". Similarly, for example, in a "rotation direction" of, for example, the impeller 1 described below, a direction from an upstream side towards a downstream side is simply called "forward", and a direction from the downstream side towards the upstream side is simply called "backward".
The names of the directions and surfaces described above do not indicate, for example, actual positional relationships and directions when installed in apparatuses.

<1. General Structure of Blower Device>

First, the blower device 100 according to an exemplary embodiment of the present invention is described. Fig. 1 is a schematic vertical sectional view of a structural example of the blower device 100. A broken line extending in an up-down direction in Fig. 1 indicates the rotary shaft of the motor 2.
As shown in Fig. 1, the blower device 100 includes the impeller 1, the motor 2 of an inner-rotor type, a motor housing 3, an external housing 4, an impeller case 5, and the circuit board 6.
The impeller 1 includes a plurality of blade members 11. The impeller 1 is provided at an upper portion of the motor 2. The impeller 1 is rotatable around the rotary shaft as a center, the rotary shaft extending in the up-down direction. The motor 2 rotationally drives the impeller 1. A structure of the motor 2 is described in detail below.
The motor housing 3 accommodates the motor 2 therein. The motor housing 3 includes an upper housing 31 and a lower housing 32. A lower end of the upper housing 31 contacts an upper end of the lower housing 32, and is connected to the upper end of the lower housing 32 by using a member (not shown), such as a screw or a rivet. A structure of the upper housing 31 is described in detail below.
The lower housing 32 includes a cylindrical portion 321, a cover portion 322, and a bearing holding portion 323. The cylindrical portion 321 extends upward in the axial direction from a peripheral edge of the cover portion 322 in the radial direction. The cover portion 322 has a central opening 322a. The central opening 322a is provided in a central portion of the cover portion 322. The bearing holding portion 323 is fitted into the central opening 322a, and holds a bearing 24b of the motor 2. The bearing holding portion 323 has an opening 323a to which the shaft 211 of the motor 2 reaches. The cylindrical portion 321 and the cover portion 322 are each a portion of the same member, and are formed separately from the bearing holding portion 323. However, the present invention is not limited to this example according to the embodiment. The cylindrical portion 321 and the cover portion 322 may be formed as separate members. Alternatively, the bearing holding portion 323 may be a portion of a member of which at least one of the cylindrical portion 321 and the cover portion 322 is a portion.
The external housing 4 is a cylindrical member extending in the axial direction. The external housing 4 is disposed outwardly of the motor housing 3 in the radial direction. Figs. 2A, 2B, and 2C are, respectively, a top perspective view, a top view, and a bottom perspective view of a structural example of the external housing 4. In the axial direction, an upper end and a lower end of the external housing 4 are open. The external housing 4 includes six holding portions 41 on an inner side surface 4a. The shape of the inner side surface 4a in the axial direction as seen from the circumferential direction is curved inward in the radial direction. For example, as shown in Fig. 1, the thickness of the external housing 4 in the radial direction is the largest at a portion thereof opposing lower portions of stationary blades 7 described below.
The impeller case 5 accommodates the impeller 1. The impeller case 5 is provided at an upper portion of the external housing 4, and covers the opening in the upper end of the external housing 4. The impeller case 5 has an opening portion 51 that is provided upwardly of the impeller 1 in the axial direction.
The circuit board 6 is a board that uses a resin material, such as epoxy. An electronic component 61 is mounted on a lower surface of the circuit board 6. The electronic component includes, for example, a control circuit and a power supply circuit of the motor 2, and is electrically connected to the motor 2 (such as, in particular, a stator 22) via a wire 62.
In the blower device 100, a gap G is formed between the motor housing 3 and the external housing 4. More specifically, the gap G is formed between an outer side surface 3a of the motor housing 3 and the inner side surface 4a of the external housing 4. Even more specifically, the gap G is formed between an outer side surface 31a of the upper housing 31 described below, an outer side surface 32a of the lower housing 32, and the inner side surface 4a of the external housing 4. In the axial direction, an upper end and a lower end of the gap G are open. Therefore, the air current F can flow through the upper end and the lower end of the gap G.
The blower device 100 causes the air current F that flows into the impeller case 5 from outside the impeller case 5 via the opening portion 51 to be generated by rotationally driving the impeller 1 by the motor 2. The air current F is sent out towards an outer side of the impeller 1 in the radial direction by the blade members 11 that rotate, and is guided to the upper end of the gap G by an inner surface of the impeller case 5. The air current F that has flown into the gap G flows downward in the axial direction through ventilation paths P between the plurality of stationary blades 7 described below, and is discharged out from the lower end of the gap G.
Fig. 3 is a local enlarged view of a structural example of the gap G between the motor housing 3 and the external housing 4. As shown in Fig. 3, a first width W_H of the upper end of the gap G in the radial direction is larger than a second width W_M in the radial direction at which the width in the radial direction at the paths becomes smallest. More specifically, the first width W_H of each ventilation path P in the radial direction at the upper end of the gap G between the motor housing 3 and the external housing 4 is larger than the second width W_M in the radial direction at which the width in the radial direction at each ventilation path P becomes smallest. The width of each ventilation path P in the radial direction gradually becomes smaller towards a downward side in the axial direction from the upper end of the gap G, and becomes smallest at an intermediate portion of each ventilation path P. Therefore, at a portion from the upper end of the gap G to the portion of the gap G having the smallest width in the radial direction, the static pressure increases in the vicinity of an inlet of each ventilation path P into which the air current F flows, so that it is possible to suppress or prevent the generation of turbulence. Consequently, it is possible to increase the blowing efficiency of air current F in the gap G between the motor housing 3 and the external housing 4.
The width of each ventilation path P in the radial direction gradually increases towards the downward side in the axial direction from the portion thereof having the smallest width in the radial direction. However, the present invention is not limited to this example according to the exemplary embodiment. The portion having the smallest width in the radial direction may be a lower end of each ventilation path P (that is, lower ends of the stationary blades 7).
The width of the gap G in the radial direction gradually increases towards the downward side in the axial direction from the lower end of each ventilation path P. A third width W_L in the radial direction at which the width of the gap G in the radial direction becomes the largest at a location below the lower ends of the stationary blades 7 in the axial direction is larger than the second width W_M in the radial direction. More specifically, at a location below the lower end of each ventilation path P in the axial direction, the third width W_L in the radial direction at which the width of the gap G, which is situated between the motor housing 3 and the external housing 4, in the radial direction becomes the largest is larger than the second width W_M in the radial direction at which the width of each ventilation path P becomes smallest. Since air resistance is reduced due to an increase in the width in the radial direction in the vicinity of an outlet of each ventilation path P, it is possible to smoothly pass the air current F in the vicinity of the outlet of each ventilation path P. Consequently, it is possible to further increase the blowing efficiency of air current F in the gap G.
In Fig. 3, the width in the radial direction at the location below the lower end of each ventilation path P (that is, at a location below the stationary blades 7) in the axial direction is the largest at the lower end of the gap G. However, the present invention is not limited to this example according to the exemplary embodiment. The width in the radial direction at the location below the lower end of each ventilation path P in the axial direction and above the lower end of the gap G in the axial direction (that is, at a location other than the lower end of the gap G) may be the third width W_L in the radial direction at which the width in the radial direction is the largest.

<2. Structure of Motor>

Next, a structure of the motor 2 is described with reference to Fig. 1. The motor 2 includes the rotor 21, the stator 22 that is ring-shaped, a bearing 24a, and the bearing 24b.
The rotor 21 is a rotor of the motor 2. The rotation angle of the rotor 21 is detected by a position detection sensor (not shown). The rotor 21 includes the shaft 211 and a plurality of magnets 212. The shaft 211 is the rotary shaft that extends in the axial up-down direction. The impeller 1 is mounted on an upper portion of the shaft 211.
The stator 22 is an armature of the motor 2, is provided at a position opposing the rotor 21, and drives the rotor 21. More specifically, when electric power is supplied to the stator 22 from an external power supply (not shown) via the circuit board 6, the rotor 21 rotates relative to the stator 22. The stator 22 includes a stator core 221, a plurality of coil portions (not shown), and an insulator 223. The stator core 221 is a laminated steel plate including electromagnetic steel plates that are laminated in the axial direction. Each coil portion is a winding member including a wire that is wound around the insulator 223. Each coil portion is provided in the circumferential direction around the shaft 211 as a center. The insulator 223 is an insulating member in which, for example, a resin material is used; and is mounted on the stator core 221 and electrically insulates a portion between the stator core 221 and each coil portion.
The bearings 24a and 24b are for example, ball bearings or sleeve bearings. The bearing 24a rotatably supports the shaft 211 at an upper side in the axial direction. The bearing 24b rotatably supports the shaft 211 at a lower side in the axial direction.

<3. Structure of Upper Housing>

Next, a structure of the upper housing 31 is described. Fig. 4 is a top perspective view of the upper housing 31. Fig. 5 is a top view of the upper housing 31. Fig. 6 is a side view of the upper housing 31. Fig. 7 is a bottom perspective view of the upper housing 31. Fig. 8 is a bottom view of the upper housing 31.
The upper housing 31 includes a cylindrical portion 311, a cover portion 312, a bearing holding portion 313, and thirteen stationary blades 7. The cylindrical portion 311 extends downward in the axial direction from a peripheral edge of the cover portion 312 in the radial direction. The cover portion 312 has a central opening 312a to which the shaft 211 reaches. The central opening 312a is provided in a central portion of the cover portion 312. The bearing holding portion 313 has a cylindrical shape that extends downward in the axial direction from a peripheral edge of the central opening 312a, and holds the bearing 24a. The cylindrical portion 311, the cover portion 312, the bearing holding portion 313, and the thirteen stationary blades 7 are portions of the same member (that is, the upper housing 31). However, the present invention is not limited to this example according to the exemplary embodiment. At least one of the cylindrical portion 311, the cover portion 312, the bearing holding portion 313, and the thirteen stationary blades 7 may be formed separately from the remaining members.
The plurality of stationary blades 7 are provided on one of side surfaces, that is, one of the outer side surface 3a of the motor housing 3 and the inner side surface 4a of the cylindrical member, the plurality of stationary blades 7 protruding towards the other side surface. In the exemplary embodiment, the thirteen stationary blades 7 are provided on the outer side surface 31a of the cylindrical portion 311 (that is, the outer side surface 31a of the upper housing 31). The present invention is not limited to this example according to the exemplary embodiment. The number of stationary blades 7 may be other than thirteen. Desirably, the number of stationary blades 7 differs from the number of blade members 11 of the impeller 1, or is a prime number. More desirably, the number of stationary blades 7 differs from the number of blade members 11 of the impeller 1, and is a prime number. This makes it possible not to allow the natural frequency generated by the upper housing 31 to overlap the vibration frequency of the motor 2. Therefore, it is possible to prevent the motor 2 from resonating.
At an outer portion of the motor housing 3 in the radial direction, the plurality of stationary blades 7 are disposed side by side in the circumferential direction and form a plurality of air-current paths. More specifically, the thirteen stationary blades 7 are disposed side by side on the outer side surface 31a in the circumferential direction, and form the plurality of ventilation paths P in the gap G between the motor housing 3 and the external housing 4. Each ventilation path P is a path provided for the air current F and extending downward in the axial direction from the upper end of the gap G.
Of the thirteen stationary blades 7 that are disposed side by side in the circumferential direction, every other stationary blade 7 including six stationary blades 7 includes a stationary blade body 74 and a protruding portion 75. Therefore, when the upper housing 31 is fitted to the external housing 4, the position of the upper housing 31 with respect to the external housing 4 in the circumferential direction is determined by insertion of the protruding portions 75 into recessed portions 42 of the corresponding holding portions 41.
Every other stationary blade 7 including the remaining seven stationary blades 7 does not include a protruding portion 75. A pair of adjacent stationary blades 7 among the thirteen stationary blades 7 do not include a protruding portion 75. However, the present invention is not limited to this example according to the exemplary embodiment. The pair of stationary blades 7 may both include a protruding portion 75.
The number of stationary blades 7 including a protruding portion 75 is not limited to this example according to the exemplary embodiment. Of the plurality of stationary blades 7 that are disposed side by side in the circumferential direction, at least one of the stationary blades 7 may include a protruding portion 75. Here, in accordance with the number of stationary blades 7 including a protruding portion 75 and the disposition of the stationary blades 7, the number of holding portions 41 on the inner side surface 4a of the external housing 4 is increased or decreased, and the disposition of the holding portions 41 is changed.
Each protruding portion 75 protrudes downward in the axial direction from a lower end of its corresponding stationary blade body 74. The shape of each protruding portion 75 may be one that allows it to be held by the corresponding holding portion 41. When the upper housing 31 is fitted to the external housing 4, the protruding portions 75 are held by the holding portions 41 on the inner side surface 4a of the external housing 4.
More specifically, when the upper housing 31 is fitted to the external housing 4, the protruding portions 75 are inserted into the recessed portions 42 of the holding portions 41. Here, lower surfaces 74a of the stationary blade bodies 74 of the stationary blades 7 including the corresponding protruding portions 75 (see Fig. 7) contact upper surfaces 41a of the holding portions 41. The position of the upper housing 31 with respect to the external housing 4 in the axial direction is determined by contact of the lower surfaces 74a with the upper surfaces 41a. Each protruding portion 75 is bonded to its corresponding holding portion 41 with an adhesive that is previously applied to at least one of the protruding portion 75 and the recessed portion 42.

<4. Detailed Structure of Stationary Blades>

Next, a detailed structure of the stationary blades 7 is described. The structure of each stationary blade 7 including the corresponding protruding portion 75 is the same as the structure of each stationary blade 7 not including a protruding portion 75 except for the protruding portion 75. Therefore, in the description below, the structure of each stationary blade 7 including the corresponding protruding portion 75 is given as an example, and the stationary blades 7 not including a protruding portion 75 are not described.
Fig. 9 is a local enlarged view of a structural example of a stationary blade 7 including a protruding portion 75. Fig. 10 is a sectional view as seen from the axial direction of a stationary blade 7 before the upper housing 31 is fitted to the external housing 4. Fig. 11 is a sectional view as seen from the axial direction of the stationary blade 7 after the upper housing 31 has been fitted to the external housing 4. The cross section of the stationary blade 7 shown in Fig. 10 is a section taken along an alternate long and short dashed line A-A in Fig. 9 before the fitting, and the cross section of the stationary blade 7 shown in Fig. 11 is a section taken along the alternate long and short dashed line A-A in Fig. 9 after the fitting.
Each stationary blade 7 protrudes outward in the radial direction from the outer side surface 31a, and extends in the axial up-down direction on the outer side surface 31a. In the gap G, each stationary blade 7 protrudes towards the inner side surface 4a of the external housing 4 from the outer side surface 31a, and extends downward in the axial direction from the upper end of the gap G.
An upper end portion of each stationary blade 7 is curved towards the back in the rotation direction of the impeller 1. More specifically, in the axial direction, an upper portion of each stationary blade 7 (in particular, an upper end portion of each stationary blade body 74) is curved towards the back in the rotation direction of the impeller 140 (towards the left in Fig. 9). Therefore, it becomes easier for the air current F generated by the rotation of the impeller 140 to flow into the ventilation paths P between the stationary blades 7.
At least one of the plurality of stationary blades 7 includes a protrusion 71. In the radial direction, the protrusion 71 protrudes from a surface of the at least one of the plurality of stationary blades 7 that faces the other side surface and contacts the other side surface. In the exemplary embodiment, each stationary blade 7 includes the corresponding protrusion 71 that extends linearly. Each protrusion 71 is provided on an outer side surface 7a of the corresponding stationary blade 7 facing outward in the radial direction. The protrusions 71 are disposed in the gap G between the upper housing 31 and the external housing 4. The protrusions 71 extend downward from an upper side along the ventilation paths P. The protrusions 71 each have a linear shape. Each protrusion 71 also protrudes towards the inner side surface 4a of the external housing 4 from the outer side surface 7a of its corresponding stationary blade 7, and contacts the inner side surface 4a.
Each protrusion 71 includes a first rib 711 and a second rib 712. Each first rib 711 and each second rib 712 are so-called thread ribs. Each first rib 711 is positioned at an edge of the corresponding stationary blade 7 that is located at a front side in the rotation direction of the impeller 1. Each first rib 711 is a protrusion that extends linearly along the edge at the front side in the rotation direction of the impeller 1. Each first rib 711 is formed from an upper end to a lower end of the edge at the front side in the rotation direction. Therefore, the first ribs 711 can suppress or prevent the air current F flowing through the ventilation paths P that are situated forwardly of the stationary blades 7 in the rotation direction from passing between the corresponding stationary blades 7 and the inner side surface 4a of the external housing 4. That is, the first ribs 711 can suppress or prevent the air current F flowing through the ventilation paths P that are situated forwardly of the stationary blades 7 in the rotation direction from flowing into the ventilation paths P that are situated backwardly of the stationary blades 7 in the rotation direction. Further, at an edge of each outer side surface 7a at the front side in the rotation direction of the impeller 1, the gap G cannot exist between the inner side surface 4a of the external housing 4 and each stationary blade 7 including the first rib 711. Therefore, it is possible to suppress the generation of turbulence at the ventilation paths P that are situated forwardly of the stationary blades 7 including the corresponding first ribs 711 in the rotation direction. Consequently, it is possible to effectively suppress a reduction in the blowing efficiency of air current F flowing through the ventilation paths P.
The first ribs 711 are not limited to that illustrated in Fig. 9, and may each be provided at a portion other than the edge of its corresponding outer side surface 7a. That is, in the rotation direction of the impeller 1, each first rib 711 may be positioned forwardly of the center of the corresponding stationary blade 7 in the circumferential direction. Even here, it is possible to suppress or prevent the air current F flowing through the ventilation paths P that are situated forwardly of the stationary blades 7 in the rotation direction from flowing into the ventilation paths P that are situated backwardly of the stationary blades 7 in the rotation direction.
Each second rib 712 is positioned at an edge of the corresponding stationary blade 7 that is located at a back side in the rotation direction of the impeller 1. Each second rib 712 is a protrusion that is provided on the outer side surface 7a of the corresponding stationary blade 7, and extends linearly upward in the axial direction from the lower end of the corresponding stationary blade 7. Therefore, even if each second rib 712 is provided on the outer side surface 7a of the corresponding stationary blade 7, in a process of manufacturing the upper housing 31, it is possible to remove the upper housing 31 from a die without interfering with the release from the die. An upper end of each second rib 712 in the axial direction contacts the corresponding first rib 711. That is, each protrusion 71 further includes the second rib 712 that extends upward in the axial direction from the lower end of the corresponding stationary blade 7 and is connected to the corresponding first rib 711. Therefore, the second ribs 712 can contribute to suppressing or preventing the air current F flowing through the ventilation paths P that are situated forwardly of the stationary blades 7 in the rotation direction from flowing into the ventilation paths P that are situated backwardly of the stationary blades 7 in the rotation direction.
In the radial direction, a height h of each first rib 711 and a height h of each second rib 712 in the radial direction are larger than the difference between the width of the gap G, which is situated between the outer side surface 31a of the upper housing 31 and the inner side surface 4a of the external housing 4, in the radial direction and the height of the corresponding stationary blade 7. Therefore, the first ribs 711 and the second ribs 712 can contact the inner side surface 4a of the external housing 4 without a gap therebetween.
More specifically, in the radial direction, the height h of each first rib 711 in the radial direction and the height h of each second rib 712 in the radial direction before fitting the upper housing 31 to the external housing 4 (see Fig. 10) is larger than a width d of the gap (see Fig. 11), which is situated between the outer side surface 7a of the corresponding stationary blade 7 and the inner side surface 4a, in the radial direction after the upper housing 31 has been fitted to the external housing 4. Therefore, when the upper housing 31 has been fitted to the external housing 4, as shown in Fig. 11, an end of each first rib 711 and an end of each second rib 712 are deformed as a result of being pressed by the inner side surface 4a, and contact at a surface thereof the inner side surface 4a along the ventilation paths P. That is, the protrusions 71 each contact at a surface thereof the other side surface. A region of the inner side surface 4a of the external housing 4 with which end portions of the first ribs 711 and end portions of the second ribs 712 contact has a certain amount of contact area.
It is desirable that the sectional shape of each first rib 711 and the sectional shape of each second rib 712 be a sectional shape that allows the ends of the first ribs 711 and the ends of the second ribs 712 to contact the inner side surface 4a of the external housing 4 without any gap therebetween when the upper housing 31 is fitted to the external housing 4. For example, the sectional shape of each first rib 711 and the sectional shape of each second rib 712 may each be one having a horn at its end as shown in Fig. 10. It is desirable that each horn have an acute angle. This makes it easier to deform the end of each first rib 711 and the end of each second rib 712. Therefore, the deformed end of each first rib 711 and the deformed end of each second rib 712 more easily contact at a surface thereof the inner side surface 4a of the external housing 4 along the ventilation paths P. Consequently, it is possible to increase the contact area of the inner side surface 4a with each stationary blade 7 and bring the first ribs 711 and the second ribs 712 into contact with the inner side surface 4a without any gap therebetween.
In the circumferential direction, portions between the first ribs 711 and the corresponding second ribs 712 are filled with an adhesive (not shown). The adhesive is an adhesive material that flows out from a portion between the lower end of each stationary blade body 74 and the corresponding holding portion 41 when inserting each protruding portion 75 into the recessed portion 42 of its corresponding holding portion 41 and bonding each protruding portion 75 to its corresponding recessed portion 42. The adhesive that has flown out to each outer side surface 7a spreads at the portion between the first rib 711 and the second rib 712 on the outer side surface 7a of its corresponding stationary blade body 74. However, the adhesive is blocked by each first rib 711 and its corresponding second rib 712. That is, the first ribs 711 and the second ribs 712 on the corresponding outer side surfaces 7a can suppress or prevent leakage of the adhesive to the ventilation paths P. Therefore, it is possible to suppress or prevent a reduction in the blowing efficiency of air current F caused by the adhesive protruding out to the ventilation paths P.

<5. Another Structural Example of Stationary Blades>

In the above-described exemplary embodiment, in order to ensure die releasability (such as upper and lower blanking process) in the process of manufacturing the upper housing 31, the protrusion 71 of each stationary blade 7 includes the corresponding second rib 712 extending in the axial direction. On the other hand, when it is possible to ensure die releasability by a method other than, for example, forming the second ribs 712, the protrusion 71 of each stationary blade 7 may include a third rib 713 extending along another edge of the corresponding outer side surface 7a in the circumferential direction. Fig. 12 is a local enlarged view of another structural example of a stationary blade 7 including a protruding portion 75.
As shown in Fig. 12, the stationary blade 7 includes a third rib 713 in addition to a first rib 711. The third rib is a thread rib. Similarly to the first ribs 711 and the second ribs 712, it is desirable that the sectional shape of the third rib 713 be a sectional shape that allows an end of the third rib 713 to contact the inner side surface 4a of the external housing 4 without any gap therebetween when the upper housing 31 is fitted to the external housing 4 (see Figs. 10 and 11).
Each third rib 713 is positioned at an edge of the corresponding stationary blade 7 that is located at a back side in the rotation direction of the impeller 1. Each third rib 713 is a protrusion that extends linearly along the edge at the back side in the rotation direction of the impeller 1. Each third rib 713 is formed from an upper end to a lower end of the edge at the back side in the rotation direction. Therefore, the third ribs 713 can suppress or prevent the air current F flowing through the ventilation paths P that are situated backwardly of the stationary blades 7 in the rotation direction from passing between the outer side surfaces 7a of the corresponding stationary blades 7 and the inner side surface 4a of the external housing 4. That is, the third ribs 713 can suppress or prevent the air current F flowing through the ventilation paths P that are situated backwardly of the stationary blades 7 in the rotation direction from flowing into the ventilation paths P that are situated forwardly of the stationary blades 7 in the rotation direction. Further, at an edge of each outer side surface 7a at the back side in the rotation direction of the impeller 1, a gap cannot exist between the inner side surface 4a of the external housing 4 and each stationary blade 7 including the third rib 713. Therefore, it is possible to suppress the generation of turbulence at the ventilation paths P that are situated backwardly of the stationary blades 7 including the corresponding third ribs 713 in the rotation direction. Consequently, it is possible to effectively suppress a reduction in the blowing efficiency of air current F flowing through the ventilation paths P.
The third ribs 713 are not limited to that illustrated in Fig. 12, and may each be provided at a portion other than the edge of its corresponding outer side surface 7a. That is, each third rib 713 may in the rotation direction of the impeller 1 be positioned backwardly of the center of the outer side surface 7a of the corresponding stationary blade 7 in the circumferential direction. In other words, each protrusion 71 may include the third rib 713 that in the rotation direction of the impeller 1 is positioned backwardly of the center of the corresponding stationary blade 7 in the circumferential direction. Even here, it is possible to suppress or prevent the air current F flowing through the ventilation paths P that are situated backwardly of the stationary blades 7 in the rotation direction from flowing into the ventilation paths P that are situated forwardly of the stationary blades 7 in the rotation direction.
Although, in Fig. 12, the protrusion 71 includes both the first rib 711 and third rib 713, the present invention is not limited to this example according to the exemplary embodiment. The protrusion 71 may include the third rib 713 in place of the first rib 711. Even here, the third rib 713 can suppress or prevent the air current F flowing through the ventilation paths P from passing between the outer side surface 7a of the stationary blade 7 and the inner side surface 4a of the external housing 4.

<6. Example of Application to Cleaner>

Next, an example in which the above-described blower device 100 is installed in a cleaner 200 is described. Fig. 13 is a perspective view of a structure of the cleaner 200 in which the blower device 100 is installed. The cleaner 200 has the blower device 100 installed therein. The cleaner 200 includes a sucking portion 210 and a body 220. The blower device 100 is installed at the body 220. A suction brush (not shown) is mounted at an intake port 211 of the sucking portion 210. The body 220 includes a dust collecting chamber 221 that is connected to the sucking portion 210, an accommodation chamber 222 that accommodates the blower device 100, and an exhaust space 223 that is connected to a plurality of exhaust ports (not shown). The opening portion 51 of the blower device 100 is connected to the dust collecting chamber 221 via a dust collecting filter (not shown). That is, the paths for air current F that is sucked by the blower device 100 are connected to the opening portion 51 of the blower device 100 via the sucking portion 210 and the dust collecting chamber 221 in that order from the intake port 211. The accommodation chamber 222 is connected to the exhaust space 223. The air current F sent out by the blower device 100 is discharged to the outside of the body 220 from the exhaust ports via the exhaust space 223. This makes it possible to realize the cleaner 200 including the blower device 100 that can effectively suppress a reduction in the blowing efficiency.
Although, in Fig. 13, the blower device 100 is installed in the cleaner 200 of a stick type, the present invention is not limited to this example according to the exemplary embodiment. The blower device 100 may be installed in cleaners of other types. The cleaner 200 may be, for example, a canister-type cleaner or a handy-type cleaner.

<7. Others>

An exemplary embodiment of the present invention has been described above. The scope of the present invention is not limited to the above-described exemplary embodiment. The present invention may be carried out by making various changes within a scope that does not depart from the gist of the present invention. The above-described exemplary embodiment may be combined as appropriate.
For example, although, in the above-described exemplary embodiment, the plurality of stationary blades 7 protrude from the outer side surface 31a of the upper housing 31, the present invention is not limited to this example. At least one of the plurality of stationary blades 7 may protrude from the inner side surface 4a of the external housing 4. In this case, the holding portion 41 that holds the lower end of the at least one of the stationary blades 7 that protrudes from the inner side surface 4a is provided on the outer side surface 3a of the motor housing 3 (such as the outer side surface 31a of the upper housing 31). That is, a plurality of stationary blades 7 may protrude inwardly in the radial direction from the inner side surface 4a of the external housing 4. The holding portions 41 that hold the lower ends of the corresponding stationary blades 7 may be provided on the outer side surface 3a of the motor housing 3. In other words, the holding portions 41 that hold the lower ends of the corresponding stationary blades 7 may be provided on the other side surface. By this, when the upper housing 31 is fitted to the external housing 4, the position of the upper housing 31 with respect to the external housing 4 in the circumferential direction is determined by insertion of the protruding portions 75 into the recessed portions 42 of the corresponding holding portions 41. Further, at least one of the plurality of stationary blades 7 may be provided on the outer side surface 32a of the lower housing 32. Alternatively, at least one of the plurality of stationary blades 7 may be provided on both the outer side surface 31a and outer side surface 32a. That is, the at least one of the stationary blades 7 may include an upper portion that protrudes from the outer side surface 31a and a lower portion that protrudes from the outer side surface 32a. Industrial Applicability
The present invention is suited for a device that sucks and sends out gas and that is required to have high static pressure. In addition to being used in the cleaner (Fig. 13), the present invention is usable in other blower devices, such as an electric fan or a ventilating fan; and is also usable in electrical devices used for other purposes, such as a drier device.

Reference Signs List

100: blower device
200: cleaner
1: impeller
11: blade member
2: motor
21: rotor
211: shaft
212: magnet
22: stator
221: stator core
223: insulator
24a, 24b: bearing
3: motor housing
3a: outer side surface
31: upper housing
31a: outer side surface
311: cylindrical portion
312: cover portion
312a: central opening
313: bearing holding portion
32: lower housing
32a: outer side surface
321: cylindrical portion
322: cover portion
322a: central opening
323: bearing holding portion
4: external housing
4a: inner side surface
41: holding portion
41a: upper surface
42: recessed portion
5: impeller case
51: opening portion
6: circuit board
61: electronic component
62: wire
7: stationary blade
7a: outer side surface
71: protrusion
711: first rib
712: second rib
713: third rib
74: stationary blade body
74a: lower surface
75: protruding portion
G: gap
P: ventilation path
F: air current

Claims

A blower device comprising:
an impeller that is rotatable around a rotary shaft as a center, the rotary shaft extending in an up-down direction;

a motor that rotationally drives the impeller;

a motor housing that accommodates the motor therein;

a cylindrical member that is disposed outwardly of the motor housing in a radial direction; and

an impeller case that accommodates the impeller,

wherein a gap is formed between an outer side surface of the motor housing and an inner side surface of the cylindrical member,

wherein a plurality of stationary blades are provided on one of side surfaces, that is, one of the outer side surface of the motor housing and the inner side surface of the cylindrical member, the plurality of stationary blades protruding towards the other side surface,

wherein, at an outer portion of the motor housing in the radial direction, the plurality of stationary blades are disposed side by side in a circumferential direction, and form a plurality of air-current paths, and

wherein at least one of the plurality of stationary blades includes a protrusion that protrudes from a surface of the at least one of the plurality of stationary blades that in the radial direction faces the other side surface and contacts the other side surface.
The blower device according to Claim 1, wherein the protrusion extends downward from an upper side along the paths.
The blower device according to either Claim 1 or Claim 2, wherein the protrusion contacts at a surface thereof the other side surface.
The blower device according to any one of Claims 1 to 3, wherein a first width of an upper end of the gap in the radial direction is larger than a second width in the radial direction at which a width in the radial direction at the paths becomes smallest.
The blower device according to Claim 4, wherein a third width in the radial direction at which a width of the gap in the radial direction becomes largest at a location below lower ends of the stationary blades in an axial direction is larger than the second width in the radial direction.
The blower device according to any one of Claims 1 to 5, wherein an upper end portion of each stationary blade is curved towards a back in a rotation direction of the impeller.
The blower device according to any one of Claims 1 to 6, wherein the protrusion includes a first rib that in a rotation direction of the impeller is positioned forwardly of a center of the at least one of the plurality of stationary blades in the circumferential direction.
The blower device according to Claim 7, wherein the first rib is positioned at an edge of the at least one of the plurality of stationary blades that is located at a front side in the rotation direction of the impeller.
The blower device according to either Claim 7 or Claim 8, wherein the protrusion further includes a second rib that extends upward in an axial direction from a lower end of the at least one of the plurality of stationary blades and that is connected to the first rib.
The blower device according to Claim 9, wherein, in the circumferential direction, a portion between the first rib and the second rib is filled with an adhesive.
The blower device according to any one of Claims 1 to 10, wherein the protrusion includes a third rib that in a rotation direction of the impeller is positioned backwardly of a center of the at least one of the plurality of stationary blades in the circumferential direction.
The blower device according to Claim 11, wherein the third rib is positioned at an edge of the at least one of the plurality of stationary blades that is located at a back side in the rotation direction of the impeller.
The blower device according to any one of Claims 1 to 12, wherein a holding portion that holds a lower end of each stationary blade is provided on the other side surface.
A cleaner comprising:
the blower device according to any one of Claims 1 to 13.