CN114144587A

CN114144587A - Variable radial inlet guide vane assembly

Info

Publication number: CN114144587A
Application number: CN202080051551.4A
Authority: CN
Inventors: P.哈利; R.凯尔; M.科利森
Original assignee: Dyson Technology Ltd
Current assignee: Dyson Technology Ltd
Priority date: 2019-07-15
Filing date: 2020-06-29
Publication date: 2022-03-04
Also published as: GB2585707A; GB201910095D0; GB2585707B; WO2021009478A1

Abstract

An air moving device is provided, comprising: a radial air inlet, an air outlet, and a cavity between the radial air inlet and the air outlet, wherein the cavity has a central axis passing through the air outlet; an air flow generator; and a plurality of guide vanes spaced about the central axis, wherein at least a portion of each vane is located in the cavity; wherein each vane has an end portion closest to the air outlet, and a second portion arranged such that the end portion is located between the second portion and the air outlet, and wherein each vane is movable relative to the radial air inlet to at least one position in which the end portion of the respective vane overlaps the air outlet less than the second portion of the respective vane overlaps the air outlet.

Description

Variable radial inlet guide vane assembly

Technical Field

The invention relates to a variable radial inlet guide vane assembly. In particular, but not exclusively, the invention relates to a variable radial inlet guide vane assembly for an air moving device, such as may be incorporated in a fan assembly.

Background

Radial inlet guide vanes are typically used to influence the direction of flow into the system or device through the radial inlet. In particular, but not exclusively, the vanes impart swirl to the flow. The direction of inflow can be influenced by changing the angle of attack of the vanes with respect to the initial flow direction.

Fan assemblies are known which use an air moving device such as an impeller located within the fan assembly to draw air in through a radial inlet before outputting accelerated air through an air outlet.

Disclosure of Invention

According to a first aspect of the present invention there is provided an air moving device comprising: a radial air inlet, an air outlet, and a cavity between the radial air inlet and the air outlet, wherein the cavity has a central axis passing through the air outlet; an air flow generator configured to receive, in use, air from the air outlet; and a plurality of guide vanes spaced about the central axis, wherein at least a portion of each vane is located in the cavity; wherein each vane has an end portion closest to the air outlet, and a second portion arranged such that the end portion is located between the second portion and the air outlet in a direction parallel to the central axis, and wherein each vane is movable relative to the radial air inlet to at least one position in which the end portion of the respective vane overlaps the air outlet less than the second portion of the respective vane overlaps the air outlet when viewed along the central axis.

In an exemplary embodiment, in at least one position, the end portion does not overlap the air outlet when viewed along the central axis.

In an exemplary embodiment, in at least one position, the second portion overlaps the air outlet when viewed along the central axis, and the end portion does not overlap the air outlet.

In the exemplary embodiment, in at least one position, the second portion overlaps the air outlet over a majority of a span of the blade parallel to the central axis when viewed along the central axis.

In an exemplary embodiment, the end portion does not overlap the air outlet when viewed along the central axis throughout the range of motion of the blade.

In the exemplary embodiment, the vanes are tapered at least partially toward their respective end portions.

In an exemplary embodiment, the vanes are pivotable about respective pivot axes parallel to the central axis so as to vary respective angles of attack of the vanes with respect to the direction of airflow from the radial air inlets.

In an exemplary embodiment, each vane is pivotable between 50 and 70 degrees from a position that is radial with respect to the central axis. In an exemplary embodiment, each vane is pivotable between 55 and 65 degrees from a position that is radial with respect to the central axis.

In the exemplary embodiment, in each blade, a span of the blade parallel to the central axis is greater than an average width of the blade perpendicular to the span.

In an exemplary embodiment, wherein the cavity includes a first boundary and a second boundary spaced from the first boundary in the direction of the central axis and having an aperture therethrough defining the air outlet, and wherein the span of each vane parallel to the central axis is at least 50% of the distance between the first boundary and the second boundary.

In an exemplary embodiment, the air moving device has one or more openings on the exterior of the device, and the device is configured such that, in use, air is drawn radially through the one or more openings to the radial air inlet.

In an exemplary embodiment, the airflow generator includes a motor-driven impeller.

In an exemplary embodiment, the air moving device comprises at least one air filter upstream of the radial air inlet.

According to a second aspect of the present invention there is provided a fan assembly comprising an air moving device according to the first aspect of the present invention and an air outlet for emitting an air flow generated by an air flow generator of the air moving device.

In an exemplary embodiment, the air outlet may be a nozzle.

According to a third aspect of the present invention there is provided a variable radial inlet guide vane assembly for conditioning air upstream of an air flow generator of an air moving device, the assembly comprising: a radial air inlet, an air outlet through which, in use, air flows from the assembly to the air flow generator, and a cavity between the radial air inlet and the air outlet, wherein the cavity has a central axis passing through the air outlet; and a plurality of guide vanes spaced about the central axis, wherein at least a portion of each vane is located in the cavity; wherein each vane has an end portion closest to the air outlet, and a second portion arranged such that the end portion is located between the second portion and the air outlet in a direction parallel to the central axis, and wherein each vane is movable relative to the radial air inlet to at least one position in which the end portion of the respective vane overlaps the air outlet less than the second portion of the respective vane overlaps the air outlet when viewed along the central axis.

Further features and advantages of the invention will become apparent from the following description of preferred embodiments of the invention, given by way of example only, which is made with reference to the accompanying drawings.

Drawings

FIG. 1 shows a cross-sectional schematic view of an example air moving device.

FIG. 2 illustrates an isometric view of an example variable radial inlet guide vane assembly.

FIG. 3 illustrates a top view of the example variable radial inlet guide vane assembly of FIG. 2.

FIG. 4 illustrates a top schematic view of the example variable radial inlet guide vane assembly of FIGS. 2 and 3.

Fig. 5 and 6 illustrate an example fan assembly.

FIG. 7 illustrates a cross-sectional view of the example fan assembly of FIGS. 5 and 6, showing the example air moving device according to FIG. 1.

Detailed Description

An air moving device comprising a variable radial inlet guide vane assembly and an air flow generator will now be described. Such an air moving device is suitable for use as part of a fan assembly. The term "fan assembly" as used herein refers to a fan assembly configured to generate and deliver a flow of air for the purposes of thermal comfort and/or environmental or climate control. Such fan assemblies are capable of producing one or more of a dehumidified air stream, a humidified air stream, a purified air stream, a filtered air stream, a cooled air stream, and a heated air stream. However, the fan assembly is equally suitable for generating air flow for other purposes, such as in a hair dryer or other hair care appliance.

FIG. 1 illustrates a cross-sectional schematic view of an exemplary air moving device 300 including a variable radial inlet guide vane assembly 100 and an air flow generator 200. Fig. 2, 3 and 4 show isometric, top view and top view schematic diagrams, respectively, of the variable radial inlet guide vane assembly 100. The variable radial inlet guide vane assembly 100 includes a main body 101, the main body 101 including a generally radial air inlet 104, an air outlet 106, and a cavity 103 between the radial air inlet 104 and the air outlet 106. The body 101 may be unitary or assembled from multiple components. The cavity 103 has a central axis 105 through an air outlet 106 of the assembly 100. The assembly 100 is disposed within a body (not shown) of the air moving device 300, the body of the air moving device 300 including an air outlet through which air is expelled from the body of the air moving device 300 (e.g., into the ambient environment, into a nozzle mounted on the body, etc.). The air flow generator 200 is mounted between the air outlet 106 of the assembly 100 and the air outlet of the main body of the air moving device 300. The air flow generator 200 has an inlet 206 to receive air from the air outlet 106 of the assembly 100. That is, in use, air will flow through the air outlet 106 of the assembly 100 to the air flow generator 200. In this example, the airflow generator inlet 206 and the air outlet 106 are circular. In other examples, the airflow generator inlet 206 and/or the air outlet 106 may be non-circular, such as elliptical or polygonal.

The assembly 100 includes a plurality of guide vanes 110 spaced about a central axis 105 of the cavity 103. At least a portion of each blade 110 is located in the cavity 103. In this example, all of each blade 110 is located in the cavity 103. In other examples, some or all of the blades 110 may protrude from the cavity 103 such that, in practice, only a portion of each protruding blade 110 is in the cavity 103. In this example, the cavity 103 has a circular cross-section, and thus the blades 110 are circumferentially spaced about the central axis 105. In other examples, the cross-section of the cavity 103 may not be circular, such as elliptical, circular, or polygonal. In this example, the cavity 103 is non-annular and does not have any obstructions between the blades 110 on opposite sides of the central axis 105.

In this example, the air moving device 300 has an opening 304 on the exterior of the device 300, and the device 300 is configured such that, in use, air is drawn radially into the radial air inlet 104 through the opening 304. In other examples, there may be only one such opening 304. In this example, the air moving device 300 includes a filter 301 located upstream of the radial air inlet 104, such that incoming air passes through the filter 301 before passing through the radial air inlet 104 and into the cavity 103. In other examples, there may be more than one filter upstream of the air inlet 104, or there may be no such filter.

Each vane 110 is movable relative to the radial air inlet 104 to vary how the vane 110 acts on air passing from the radial air inlet 104 and into the cavity 103 in use. In this example, but not all examples, the blades 110 may pivot about respective pivot axes 115 that are parallel to the central axis 105. In some examples, the pivot axis 115 of a given blade 110 may pass through any portion of the blade 110, such as substantially along an edge of the blade 110 or through a central portion of the blade 110. In other examples, pivot axis 115 may be remote from blade 110. The movement of each blade 110 is configured to affect the direction of radial inflow 107 from outside the assembly 100 through the radial air inlet 104 (and in this example, through the opening 304 and the filter 301) to impinge on the blade 110. For example, varying the angle of attack α of each vane 110 relative to the radial inflow 107 from the radial air inlet 104 may induce a tangential velocity or "swirl" in the radial inflow 107. If a given blade 110 is aligned with the radial inflow 107, the angle of attack α is zero and the blade 110 does not induce such a vortex. In some examples, it may be desirable to induce swirl to increase the operating range of the air moving device 300. Such pre-swirl flow in the air moving device 300 may provide, for example, a higher efficiency or a lower acoustics of the air moving device 300 before the air reaches the air flow generator 200 mounted downstream of the assembly 100. It should be appreciated that the generally radial air inlet 104 may allow for a radial inflow 107 at an angle other than strictly normal to the central axis 105, but still in a generally radial direction. Such radial air inlets 104 may themselves be so inclined with respect to the central axis 105.

Each guide vane 110 of fig. 1 to 4 has a span 113 parallel to the central axis 105. Each blade 110 also has a trailing edge 114 facing into the cavity 103 and an opposite leading edge 117. In this example, the leading edge 117 faces the radial air inlet 104. Each guide vane 110 has an end portion 118 closest to the air outlet 106, and a second portion 119 arranged such that the end portion 118 is located between the second portion 119 and the air outlet 106 in a direction parallel to the central axis 105. The end portion 118 has a first width 111 and the second portion 119 has a second width 112. The first and

second widths

111, 112 are each perpendicular to the span 113. Each blade 110 of the present example has an Aspect Ratio (AR) greater than 1. AR is defined as the ratio between the span 113 and the average width of the blade 110. In some examples, the AR may be between 1 and 4, such as about 3. In some examples, AR may be greater than 4.

The inventors have realised that a large blade width may be ideal for achieving high swirl angles, but turbulent wakes from blades having a large width may undesirably interact with downstream air flow generators, particularly if the available space within the air moving device is limited. This interaction may generate additional vibration or noise. Alternatively or additionally, the efficiency of the air moving device may be reduced. The present invention seeks to mitigate the interaction of turbulent wakes with the air flow generator 200 while still imparting high swirl angles.

This effect is achieved by ensuring that each vane 110 is movable relative to the radial air inlet 104 to at least a position in which the end portion 118 closest to the air outlet 106 and hence the air moving device 200 overlaps the air outlet 106 less than the second portion 119 when viewed along the central axis 105. In this example, this is because the first width 111 is smaller than the second width 112. Indeed, in this example, when the blade 110 is in the at least one position, the end portion 118 does not overlap the air outlet 106 at all, when viewed along the central axis 105. Further, in this example, in at least one position, the second portion 119 overlaps the air outlet 106, and the end portion 118 does not overlap the air outlet 106.

In this example, the second width 112 of each blade 110 is greater than the first width 111 along a majority of the span 113 of the blade 110 such that, in at least one position, the second portion 119 overlaps the air outlet 106 over a majority of the span 113 of the blade when viewed along the central axis. In this example, the second width 112 is also constant along a majority of the span 113 of the blade 110. In other examples, the second width 112 may vary along a majority of the span 113 of the blade 110, such as less than 10%. In this example, the first width 111 is non-zero. In other examples, the first width 111 is zero such that the end of the vane 110 closest to the air outlet 106 is pointed (e.g., tapered to a point).

In the present example, the blades 110 are tapered to their respective end portions 118, as indicated by reference numeral 116. That is, a portion of the trailing edge 114 of the blade 110 is tapered. In each blade 110, the taper 116 reduces the strength of the wake exiting the trailing edge 114 of the blade 110 and entering the air moving device 200, while still allowing the blade 110 to impart a high swirl angle due to the relatively long width along another portion (in this case, a majority) of the span 113 of the blade 110. In other examples, the width of each blade 110 may decrease toward the end portion 118 by any one or combination of: a convex fillet; concave round corners; chamfering; and at least one step. In the present example, the leading edge 117 and trailing edge 114 of each blade 110 are substantially parallel to the central axis 105, except for the taper 116.

As mentioned above, in this example the guide vanes 110 are pivotally mounted with respect to the cavity 103, the radial air inlet 104 and the central axis 105. In other examples, the blade 110 may move relative to the cavity 103, the radial air inlet 104, and the central axis 105 as a translation or a combination of translation and rotation. The assembly 100 may include any suitable actuator (not shown) for moving the blade 110 relative to the cavity 103, the radial air inlet 104, and the central axis 105.

In this example, the air flow generator 200 has an axis of rotation that is aligned with the central axis 105 of the cavity 103. That is, the central axis 105 of the cavity 103 and the axis of rotation of the air flow generator 200 coincide. In other examples, the central axis 105 of the cavity 103 and the axis of rotation of the air flow generator 200 may be offset, such as parallel to each other.

As described above, the vortex is induced by varying the angle of attack α of the blades 110 with respect to the incoming air. If the blades 110 are aligned with the incoming air 107, the angle of attack α will be zero. If the angle of attack α is zero, the incoming air 107 may enter the device 300 or assembly 100 substantially radially (e.g., perpendicular to the central axis 105), change direction within the cavity 103, and pass through the air outlet 106 substantially axially (e.g., parallel to the central axis 105). In this case, the blades 110 may not impart a tangential component of velocity into the flow, but they may still create a wake. If the blades 110 are instead disposed at an angle of attack a greater than zero degrees, the incoming air 107 will enter the device substantially radially, impinge on the surface of the blades 110, and continue to pass tangentially and axially through the cavity 103. The air flow generator 200 will thus receive pre-swirl air, potentially improving the performance characteristics of the air moving device as described above.

As previously discussed, the present inventors have recognized that increasing the width of each blade 110 may create more turbulence, thereby improving the characteristics of the air moving device 300. However, the inventors have also recognized that the wake emitted from a blade 110 having a long width may negatively impact the operation of the air moving device 300 at a small angle of attack α. This may be particularly relevant in devices with a limited spatial envelope, such as the examples shown in fig. 1 to 4, where a blade 110 having a long width may overlap with the air outlet 106 when viewed along the central axis 105 at a small angle of attack α. Given that the end portion 118 of each vane 110 has less overlap with the air outlet 106 than the second portion when viewed along the central axis 105 as previously described, the advantage of a reduced wake intensity exiting the vane 110 and entering the air flow generating device 200 is provided, while still providing a high swirl angle elsewhere along the vane 110. In the present example, the end portion 118 of each vane 110 does not overlap the air outlet 106 when viewed along the central axis 105 throughout the range of motion of each vane 110. This results in an advantage being obtained regardless of the angle of attack a at which the blade 110 is located. In some other examples, in each vane 110, the end portion 118 of the vane 110 may slightly overlap the air outlet 106 (but less than the overlap of the second portion 119 of the vane with the air outlet 106), still providing similar advantages.

In some examples, the vane 110 may pivot between a zero degree angle a (the angle at which the vane 110 is radially aligned with the central axis 105) and about a 60 degree angle a relative to the radial direction of the central axis 105 relative to the cavity 103, the radial air inlet 104, and the central axis 105. In some examples, the upper limit of this range of motion of the blade 110 may be another angle between 50 and 70 degrees, optionally between 55 and 65 degrees. For example, the upper limit may be greater than 40 degrees, greater than 50 degrees, or greater than 55 degrees. For example, the upper limit may be less than 80 degrees, less than 70 degrees, or less than 65 degrees.

FIG. 4 shows one of the blades 110 in two states: the angle of attack α is zero degrees and the angle of attack α is 60 degrees. In the present example, when the blade 110 is at an angle of attack α of 60 degrees, the second portion 119 of the blade 110 does not overlap the air outlet 106 when viewed along the central axis 105. Preferably, when the blade 110 is positioned at an angle of attack α of 60 degrees, the trailing edge 114 of the blade 110 is incident at the boundary with the air outlet 106 or the air flow generator inlet 206. In other examples, the trailing edge 114 of the blade 110 may be incident with the boundary of the air outlet 106 or the airflow generator inlet 206 at other angles of attack α, such as 30 degrees, 40 degrees, 50 degrees, or greater than 60 degrees, when viewed along the central axis 105. In other examples, the trailing edge 114 of the blade 110 may overlap the air outlet 106 or the airflow generator inlet 206 at all angles of attack α, or may not overlap at angles of attack greater than a predetermined size (e.g., 60 degrees). However, since the second portion 119 of the vane 110 is spaced from the air outlet 106 in a direction parallel to the central axis 105, such overlap may have negligible or no effect on the performance of the assembly 100 or device 300.

Fig. 5 and 6 illustrate an example fan assembly 500 including the air moving device 300 shown in fig. 1 and a nozzle 400 for emitting an air flow generated by the air moving device 300. In some examples, the nozzle 400 may define an opening through which air from outside the fan assembly is drawn in use by the air stream emitted from the nozzle 400. In other examples, air may be emitted through air outlets of the fan assembly 500 other than the nozzles. FIG. 7 illustrates a cross-sectional view on section A-A of the example fan assembly 500 of FIG. 6, highlighting the air moving device 300 of FIG. 1 and its variable radial inlet guide vane assembly 100 of FIGS. 1-4.

It will be understood that each of the items described above can be used alone or in combination with other items shown in the figures or described in the specification, and that items mentioned in the same paragraphs as each other or in the same drawings as each other need not be used in combination with each other. Furthermore, the expression "means" may be replaced by an actuator or a system or device as required. Furthermore, any reference to "comprising" or "consisting of …" is not intended to be limiting in any way, and the reader should interpret the description and claims accordingly.

Furthermore, while the present invention has been described in terms of preferred embodiments as described above, it should be understood that these embodiments are merely illustrative. In view of this disclosure, those skilled in the art will be able to make modifications and substitutions that fall within the scope of the appended claims. For example, those skilled in the art will appreciate that the above-described invention may be equally applicable to other types of environmentally controlled fan assemblies, not just stand alone fan assemblies. Such a fan assembly may be, for example, any of a stand-alone fan assembly, a ceiling or wall mounted fan assembly, and a vehicle mounted fan assembly. Furthermore, the above invention may be equally applicable to other types of air flow generating devices or blowers, such as hair dryers or other hair care appliances.

Further, in the example shown in fig. 7, the airflow generator includes a motor-driven impeller. However, the air flow generator may be of a different form. Further, in the example shown in fig. 7, the impeller is in the form of a mixed flow impeller comprising a generally conical hub, a plurality of impeller blades connected to the hub, and a generally frustoconical shroud connected to the blades so as to surround the hub and blades. However, the impeller may also be of a different form, such as an axial or radial impeller.

Claims

1. An air moving device comprising:

a radial air inlet, an air outlet, and a cavity between the radial air inlet and the air outlet, wherein the cavity has a central axis passing through the air outlet;

an air flow generator configured to receive, in use, air from the air outlet; and

a plurality of guide vanes spaced about the central axis, wherein at least a portion of each vane is located in the cavity;

wherein each vane has an end portion closest to the air outlet and a second portion arranged such that the end portion is located between the second portion and the air outlet in a direction parallel to the central axis, and wherein each vane is movable relative to the radial air inlet to at least one position in which the end portion of the respective vane overlaps the air outlet less than the second portion of the respective vane overlaps the air outlet when viewed along the central axis.

2. The device of claim 1, wherein, in the at least one position, the end portion does not overlap the air outlet when viewed along the central axis.

3. The device of claim 1 or 2, wherein, in the at least one position, the second portion overlaps the air outlet over a substantial part of the span of the blade parallel to the central axis, when viewed along the central axis.

4. A device according to any one of claims 1 to 3, wherein the end portion does not overlap the air outlet over the full range of motion of the blade when viewed along the central axis.

5. A device according to any one of claims 1 to 4, wherein the vanes are tapered at least partially towards their respective end portions.

6. A device according to any one of claims 1 to 5, wherein the vanes are pivotable about respective pivot axes parallel to the central axis so as to vary the respective angles of attack of the vanes relative to the direction of airflow from the radial air inlet.

7. The device of any one of claims 1 to 6, wherein each vane is pivotable between 50 and 70 degrees from a position radial to the central axis.

8. A device according to any one of claims 1 to 7, wherein in each blade the span of the blade parallel to the central axis is greater than the average width of the blade perpendicular to that span.

9. The device of any one of claims 1 to 8, wherein the cavity comprises a first boundary and a second boundary, wherein the second boundary is spaced from the first boundary in the direction of the central axis and has a hole therethrough defining the air outlet, and wherein the span of each vane parallel to the central axis is at least 50% of the distance between the first and second boundaries.

10. A device according to any one of claims 1 to 9, wherein the device has one or more openings on the exterior of the device and the device is configured such that, in use, air is drawn radially through the one or more openings to the radial air inlet.

11. The device of any one of claims 1 to 10, wherein the air flow generator comprises a motor-driven impeller.

12. The device of any preceding claim, wherein the device comprises at least one filter upstream of the radial air inlet.

13. A fan assembly comprising an air moving device according to any one of claims 1 to 12 and an air outlet for emitting an air flow generated by an air flow generator of the air moving device.

14. A variable radial inlet guide vane assembly for conditioning air upstream of an air flow generator of an air moving device, the assembly comprising:

a radial air inlet, an air outlet through which, in use, air flows from the assembly to the air flow generator, and a cavity between the radial air inlet and the air outlet, wherein the cavity has a central axis passing through the air outlet; and

15. The assembly of claim 14, wherein, in the at least one position, the end portion does not overlap the air outlet when viewed along the central axis.

16. The assembly according to any one of claims 14 and 15, wherein in said at least one position, said second portion overlaps said air outlet over a substantial part of the span of the blade parallel to the central axis, when viewed along said central axis.

17. The assembly of any one of claims 14 to 16, wherein the end portion does not overlap the air outlet over the full range of motion of the blade when viewed along the central axis.

18. An assembly according to any one of claims 14 to 17, wherein the vanes are tapered at least partially towards their respective end portions.

19. An assembly according to any one of claims 14 to 18, wherein the vanes are pivotable about respective pivot axes parallel to the central axis so as to vary the respective angles of attack of the vanes relative to the direction of airflow from the radial air inlet.

20. An assembly according to any one of claims 14 to 19, wherein in each blade, the span of the blade parallel to the central axis is greater than the average width of the blade perpendicular to that span.