WO2018173803A1

WO2018173803A1 - Blower device

Info

Publication number: WO2018173803A1
Application number: PCT/JP2018/009210
Authority: WO
Inventors: 翔太吉川; 正宏重森
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2017-03-24
Filing date: 2018-03-09
Publication date: 2018-09-27
Also published as: JP2018159371A

Abstract

This blower device is provided with: an axial flow impeller comprising a hub which has a rotation axis, and also comprising a plurality of blades (8) arranged around the hub; a motor rotating about the rotation axis; and a bell mouth (4) surrounding the axial flow impeller. The blades (8) each have, as the outer peripheral portion thereof: a blade front edge (13) located on the upstream side in an air flow direction; a blade rear edge (14) located on the downstream side in the air flow direction; and a blade end (15) extending from the radially outer side of the blade front edge (13) to the radially outer side of the blade rear edge (14). When viewed in the direction of the rotation axis, the maximum diameter (Df) of the axial flow impeller is larger than the minimum diameter (Db) of the bell mouth (4), and in the region in which the blades (8) and the bell mouth (4) overlap when viewed in the direction of the rotation axis, the distance between the bell mouth (4) and the blade ends (15) which face the bell mouth (4) is larger on the radially outer peripheral side than on the radially inner peripheral side.

Description

Blower

The present invention relates to a blower device having a fan motor having a fan mounted therein and having a bell mouth on the indoor side in a shape disposed in a ventilation port provided in a room wall.

Conventionally, a configuration in which a blower is fixed to a frame body and the frame body is installed on a wall surface hollowed into a frame shape is known (see, for example, Patent Document 1).

Hereinafter, the blower will be described with reference to FIGS.

FIG. 4 is a schematic view of a conventional blower. FIG. 5 is a schematic view of the vicinity of a fan of a conventional blower.

As shown in FIG. 4, the blower main body 101 has a bell tube 103 formed around the fan 102 by assembling a motor (not shown), a fan 102 and the like to a rectangular tube frame. In such a blower, it is known that the air boosted by the pressure surface of the blade flows out from the blade tip that is the outer periphery of the blade and the blade tip vortex is generated, thereby reducing the blowing performance. As shown in FIG. 5, it is known that the gap 104 (clearance) between the bell mouth 103 and the fan 102 greatly affects the suppression of the influence of the blade tip vortex.

For example, a similar prior document is described in Patent Document 1 below.

JP 2007-040198 A

However, in the conventional blower, since the distance between the bell mouth and the fan blade is always constant, the suction port from the radial direction of the blade becomes narrow and sufficient suction cannot be performed, thereby improving the efficiency. There was a problem that it was not possible.

Therefore, the present invention solves the above-described problems, and an object thereof is to provide a blower device that improves the efficiency of work performed by the blades.

The blower according to one aspect of the present invention includes a hub having a rotation shaft, an axial impeller composed of a plurality of blades arranged around the hub, a motor rotating around the rotation shaft, an axial flow A bell mouth is provided around the impeller. The blade has, as an outer peripheral portion, a blade leading edge that is upstream with respect to the air flow, a blade trailing edge that is downstream with respect to the air flow, and a blade trailing edge from the radial outside of the blade leading edge. It has a blade blade tip to the outside in the radial direction. When viewed from the direction of the rotation axis, the maximum diameter of the axial impeller is larger than the minimum diameter of the bell mouth, and when viewed from the direction of the rotation axis, it faces the bell mouth in the region where the blade and the bell mouth overlap. The distance between the blade blade tip and the bell mouth is larger on the outer peripheral side than on the inner peripheral side in the radial direction.

According to the present invention, the efficiency of work performed by the blades can be improved.

FIG. 1 is a perspective view of a ventilation fan according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the ventilation fan according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of the vicinity of the blade and the bell mouth according to the embodiment of the present invention. FIG. 4 is a schematic view of a conventional blower. FIG. 5 is a schematic view of the vicinity of a fan of a conventional blower.

A blower according to an aspect of the present invention includes a hub having a rotating shaft, an axial flow impeller composed of a plurality of blades arranged around the hub, a motor rotating around the rotating shaft, and an axial flow impeller. With a bell mouth surrounding. The blade has, as an outer peripheral portion, a blade leading edge that is upstream with respect to the air flow, a blade trailing edge that is downstream with respect to the air flow, and a blade trailing edge from the radial outside of the blade leading edge. The blade blade tip extends to the outside in the radial direction. When viewed from the direction of the rotation axis, the maximum diameter of the axial impeller is larger than the minimum diameter of the bell mouth, and when viewed from the direction of the rotation axis, it faces the bell mouth in the region where the blade and the bell mouth overlap. The distance between the blade blade tip and the bell mouth is larger on the outer peripheral side than on the inner peripheral side in the radial direction.

According to this configuration, the distance between the blade and the bell mouth on the upstream side is larger than the distance between the blade and the bell mouth on the downstream side. Therefore, the area of the portion sucked into the blade from the radial direction becomes larger than when the distance between the blade and the bell mouth on the upstream side and the distance between the blade and the bell mouth on the downstream side are made constant. Therefore, since it becomes easy to inhale the air from the radial direction of a blade | wing, it can blow efficiently.

Further, in the air blower according to the embodiment of the present invention, the distance from the arbitrary point of the blade wing tip facing the bell mouth to the bell mouth is the minimum distance between the axial flow impeller and the bell mouth. A certain region where a certain clearance distance is constant may be provided.

This reduces the loss because the distance between the blade and the bell mouth is constant in a certain downstream area, so that the generation of the blade tip vortex is suppressed. Therefore, it can blow efficiently.

The air blower according to the embodiment of the present invention may be provided with a tapered region between the axial-flow impeller and the bell mouth that increases on the upstream side as the clearance distance increases toward the upstream side.

This makes it easier to inhale air from the radial direction of the blade than when the distance between the blade and the bell mouth is constant. Furthermore, since the distance between the blade blade tip and the bell mouth decreases toward the downstream side, the air pressurized by the blade can be efficiently blown.

In the air blower according to the embodiment of the present invention, a part of the bell mouth on the downstream side of the fixed region may be parallel to the rotation axis in the plane including the rotation axis.

This makes it possible to rectify the downstream airflow and reduce the loss on the downstream side, so that air can be blown efficiently.

In the air blower according to the embodiment of the present invention, the shape of the blade blade tip in the tapered region may be a linear shape on the plane including the rotation axis.

This allows the air to be boosted little by little, so that air can be blown efficiently.

Further, in the air blower according to the embodiment of the present invention, the tapered portion corresponding to the tapered region of the blade blade tip and the fixed portion corresponding to the fixed region of the blade blade tip may be tangent on the plane including the rotation axis.

Hereinafter, an embodiment of the present invention will be described using a ventilating fan as an example of a blower to provide an understanding of the present invention. The following embodiments are examples embodying the present invention, and do not limit the technical scope of the present invention. Moreover, the same number is attached | subjected about the same site | part through all the drawings. Furthermore, in each drawing, the description of the details of each part not directly related to the present invention is omitted.

(Embodiment)
FIG. 1 is a perspective view of a ventilation fan according to an embodiment of the present invention.

As shown in FIG. 1, a ventilation fan 1 according to the present embodiment includes a square tube frame 2 and a motor 11 (see FIG. 2), an axial flow impeller 3, and a bell mouth 4. The ventilation fan 1 is provided on a wall surface that partitions the inside and outside of the room, and is used under the condition that the suction side of the indoor space 6 is an open space without an obstacle.

The axial flow impeller 3 includes a hub 9 having a rotating shaft 12 and a plurality of blades 8 arranged around the hub 9. In the present embodiment, five blades 8 are arranged around the hub 9. Note that at least two blades 8 are sufficient. Moreover, in this Embodiment, although all the blade | wings 8 are the same shapes, it is not limited to this.

The blade 8 has a blade leading edge 13, a blade trailing edge 14, and a blade blade tip 15 as outer peripheral portions. The blade leading edge 13 is a portion on the upstream side with respect to the air flow. The blade trailing edge 14 is a portion on the downstream side with respect to the air flow. The blade tip 15 is a portion from the outside in the radial direction of the blade leading edge 13 to the outside in the radial direction of the blade trailing edge 14.

The motor 11 rotates the axial impeller 3 by rotating around the rotating shaft 12.

The bell mouth 4 is provided on the front panel 5 so as to surround the axial flow impeller 3.

The front panel 5 is provided as an outline of the ventilation fan 1. Here, the front panel 5 is provided with an opening 24. The front panel 5 includes a bell mouth 4 that surrounds the opening 24 and a planar portion 7 around the bell mouth 4. It can also be said that the bell mouth 4 is provided on the periphery of the opening 24. The flat surface portion 7 has a substantially flat shape so as not to disturb the flow along the front panel 5. The bell mouth 4 is formed of a curved surface that smoothly narrows from the flat surface portion 7 toward the opening portion 24. Further, the diameter of the surface of the bell mouth 4 perpendicular to the rotating shaft 12 decreases from the suction side, which is the upstream side, toward the outlet side, which is the downstream side, that is, toward the blowing direction 10.

According to such a configuration, the axial-flow impeller 3 rotated by the motor 11 sends air in the direction of the blowing direction 10. And since the bellmouth 4 sends out air smoothly from the suction side to the blowing side, it contributes to the improvement of the ventilation efficiency of the ventilation fan 1. FIG.

FIG. 2 is a sectional view of the ventilation fan according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of the vicinity of the blade and the bell mouth according to the embodiment of the present invention.

2 and 3 are sectional views of the bell mouth 4 in a plane including the rotation shaft 12 of the ventilation fan 1 of the embodiment, and this plane is the outer peripheral portion of the blade 8 (the blade leading edge 13, the blade trailing edge 14, the blade The trajectory through which the blade tip 15) passes is illustrated. FIG. 2 shows a radial cross section of the front panel 5 provided with the bell mouth 4 of the embodiment, and an outline of the positions of the axial-flow impeller 3 and the motor 11. FIG. 3 is a cross-sectional view of the vicinity of the blade 8 and the bell mouth 4. 2 and 3, the upper side, that is, the upstream side of the air flow is defined as the suction side, and the lower side, that is, the downstream side of the air flow is defined as the outlet side.

The axial flow impeller 3 rotates around the rotation shaft 12 and blows air from the blade leading edge 13 of the blade 8 on the upstream side of the air flow toward the blade trailing edge 14 of the blade 8 on the downstream side.

As described above, the bell mouth 4 has a shape in which the diameter in the plane perpendicular to the rotating shaft 12 decreases as it goes from the suction side to the blowout side. In other words, the bell mouth 4 has a shape having a minimum diameter Db at the most downstream position 18. On the downstream side of the bell mouth 4, a straight portion 16 that is parallel to the rotating shaft 12 is provided in order to rectify the airflow that is blown out.

The blade 8 is attached such that the trailing edge blade tip 17 that is the intersection of the blade trailing edge 14 and the blade blade tip 15 coincides with the most downstream position 18 of the bell mouth 4 in the direction of the rotating shaft 12. In other words, the trailing edge blade tip 17 and the most downstream position 18 are on the same plane in a plane perpendicular to the rotation axis 12.

The axial flow impeller 3 has a maximum diameter Df at a leading edge blade tip 19 which is an intersection of the blade leading edge 13 and the blade blade tip 15 on a plane perpendicular to the rotating shaft 12. Here, the maximum diameter Df is larger than the minimum diameter Db. In other words, as shown in FIG. 3, the ventilation fan 1 has a configuration in which the blade 8 and the bell mouth 4 overlap each other in the range from the minimum diameter Db to the maximum diameter Df when viewed from the direction of the rotation axis 12. . The clearance distance 21 between the blade wing tip 15 and the bell mouth 4 is configured to be largest at the position of the maximum diameter Df in the common region 20. Here, the clearance distance 21 is a minimum distance from an arbitrary point of the blade wing tip 15 facing the bell mouth 4 to the bell mouth 4.

As shown in FIG. 3, a taper region 22 is provided between the axial flow impeller 3 and the bell mouth 4 on the suction side that is the upstream side, and is constant on the outlet side that is the downstream side of the taper region 22. A region 23 is provided.

In the taper region 22, the clearance distance 21 decreases from the upstream side to the downstream side. Further, the shape of the blade blade tip 15 in the tapered region 22 is a linear shape.

In the constant region 23, the clearance distance 21 is constant. In other words, in the fixed region 23, a cylinder formed in contact with the most downstream position 18 of the bell mouth 4 and a virtual cylinder formed by rotating the blade blade tip 15 in the fixed region 23 are concentric. These two cylinders have the rotation axis 12 as a central axis. In addition, the shape of the blade blade tip 15 in the fixed region 23 is a shape that follows the shape of the bell mouth 4. And the taper part 22a which corresponds to the taper area | region 22 of the blade blade | wing tip 15 and the fixed part 23a which corresponds to the fixed area | region 23 are smoothly connected so that it may tangent. In this way, the air can be gradually increased on the positive pressure surface of the blade 8.

In this way, by increasing the clearance distance 21 on the upstream side, the suction of air from the radial direction of the blade 8 is sufficiently performed as compared with the case where the clearance distance 21 is constant in the entire region. Therefore, the ventilation fan 1 can inhale air efficiently. Further, by maintaining the clearance distance 21 constant on the downstream side, generation of blade tip vortices can be suppressed. Therefore, the ventilation fan 1 can blow air more efficiently than when the clearance distance 21 is constant in the entire region.

The blower and the ventilating fan according to the present invention are useful as a technology expected to be used as a fan having an axial fan and a bell mouth structure for home use or office use.

DESCRIPTION OF SYMBOLS 1 Ventilation fan 2 Frame body 3 Axial flow impeller 4 Bell mouth 5 Front panel 6 Indoor space 7 Plane portion 8 Blade 9 Hub 10 Air blowing direction 11 Motor 12 Rotating shaft 13 Blade leading edge 14 Blade trailing edge 15 Blade blade end 16 Linear portion 17 trailing edge blade tip 18 most downstream position 19 leading edge blade tip 20 common region 21 clearance distance 22 taper region 22a taper portion 23 constant region 23a constant portion 24 opening

Claims

An axial flow impeller comprising a hub having a rotating shaft and a plurality of blades arranged around the hub;
A motor that rotates about the rotating shaft, and a bell mouth that surrounds the axial impeller,
The blade includes, as an outer peripheral portion, a blade leading edge that is upstream with respect to the air flow, a blade trailing edge that is downstream with respect to the air flow, and the radially outer side of the blade leading edge. It has the blade tip to the outside in the radial direction of the blade trailing edge,
When viewed from the rotational axis direction, the maximum diameter of the axial flow impeller is larger than the minimum diameter of the bell mouth,
When viewed from the rotational axis direction, in the region where the blade and the bell mouth overlap, the distance between the blade blade end facing the bell mouth and the bell mouth is closer to the outer peripheral side than the inner peripheral side in the radial direction. A blower characterized by being large.
Between the axial flow impeller and the bell mouth,
2. The blower according to claim 1, wherein a constant region in which a clearance distance that is a minimum distance from an arbitrary point of the blade wing tip facing the bell mouth to the bell mouth is constant is provided on the downstream side. .
Between the axial flow impeller and the bell mouth,
The air blower according to claim 2, wherein a taper region in which the clearance distance increases toward the upstream side is provided on the upstream side.
The blower according to claim 2, wherein a part of the bell mouth on the downstream side of the fixed region is parallel to the rotation axis in a plane including the rotation axis.
The air blower according to claim 3, wherein a shape of the blade blade tip in the tapered region is a linear shape in a plane including the rotation axis.
The air blower according to claim 3, wherein, in a plane including the rotation axis, a tapered portion corresponding to the tapered region of the blade blade tip and a fixed portion corresponding to the fixed region of the blade blade tip are tangent.