WO2022245828A1

WO2022245828A1 - Fans and fan blades having adjustable flaps

Info

Publication number: WO2022245828A1
Application number: PCT/US2022/029638
Authority: WO
Inventors: Victor Manuel GUTIERREZ RODRIGUEZ; Karen Citlalli DAVALOS BELLO
Original assignee: Vmg Ventilation Services Llc
Priority date: 2021-05-20
Filing date: 2022-05-17
Publication date: 2022-11-24

Abstract

A fan may include a hub; a plurality of blades attached to the hub; and a motor configured to rotate the hub; wherein each of the plurality of blades includes: a blade body; and at least one flap slidably and removably engaged with the blade body in a generally spanwise direction; wherein the at least one flap is configurable in a plurality of pitch positions about a generally spanwise axis. In some embodiments, a plurality of flaps may be installed on a blade body at different segments along the spanwise length of the blade body. In some embodiments, a plurality of flaps having one or more different characteristics may be interchangeably installed on a given blade body.

Description

FANS AND FAN BLADES HAVING ADJUSTABLE FLAPS CROSS REFERENCE TO RELATED APPLICATIONS

[001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 63/190,958 filed May 20, 2021, the full disclosure of which is incorporated herein by reference.

FIELD

[002] This application relates generally to fans, such as ceiling fans.

BACKGROUND

[003] This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.

[004] In the field of fans for movement of air, such as ceiling fans, for example, one of the challenges is a need to provide different airflow characteristics in various regions of the fan blades. For example, for a given angular velocity of a constant cross-section fan blade, the airflow generally increases as the radial distance from the fan hub increases along the span of the fan blade, such that the airflow near the tip of the blade may be substantially greater than the airflow in the vicinity of the hub. In some instances, it would be desirable to generate greater airflow in the vicinity of the hub. Additionally, it would be beneficial to provide the ability to modify the airflow characteristics of a fan blade without having to remove the fan blade from the hub.

SUMMARY [005] A fan may include a hub; a plurality of blades attached to the hub; and a motor configured to rotate the hub; wherein each of the plurality of blades includes: a blade body; and at least one flap slidably and removably engaged with the blade body in a generally spanwise direction; wherein the at least one flap is configurable in a plurality of pitch positions about a generally spanwise axis. In some embodiments, a plurality of flaps may be installed on a blade body at different segments along the spanwise length of the blade body.

In some embodiments, a plurality of flaps having one or more different characteristics may be interchangeably installed on a given blade body.

[006] In some embodiments, the at least one flap includes an inboard flap and an outboard flap. In some embodiments, the inboard flap includes one or more characteristics that are the same as the outboard flap. In some embodiments, the one or more characteristics are selected from airfoil shape, chord length, span, camber, angle of attack, planform area, aspect ratio, and a combination thereof. In some embodiments, the inboard flap includes one or more characteristics that are different from the outboard flap. In some embodiments, the one or more characteristics are selected from airfoil shape, chord length, span, camber, angle of attack, planform area, aspect ratio, and a combination thereof. In some embodiments, the inboard flap has a chord length Ci that is greater than a chord length C₀ of the outboard flap. In some embodiments, the inboard flap is configured at a greater angle of attack than the outboard flap. In some embodiments, at least one of the inboard flap and the outboard flap includes a transition portion in the vicinity of an interface between the inboard flap and the outboard flap.

[007] In some embodiments, the blade body and the at least one flap are configured with complementary connection structures whereby the at least one flap is slidably engaged with the blade body in a generally spanwise direction but otherwise substantially fixed in relation to the blade body. In some embodiments, the at least one flap includes an inboard flap and an outboard flap; and the inboard flap is placeable in a first orientation with respect to the blade body and the outboard flap is placeable in a second orientation with respect to the blade body.

[008] In some embodiments, the complementary connection structures include a tongue-in-groove connection. In some embodiments, the at least one flap includes a leading edge having a tongue; and the blade body includes a trailing edge having a plurality of protrusions extending rearwardly from a wall, wherein the plurality of protrusions define a plurality of grooves configured to slidingly and removably receive the tongue.

[009] In some embodiments, the complementary connection structures further include complementarily shaped bearing surfaces configured for spanwise sliding engagement with each other.

[0010] In some embodiments, the at least one flap is adjustable for placement at a first angle of attack and a second angle of attack.

[0011] In some embodiments, the complementary connection structures include a toothed connection wherein the blade body includes a first plurality of teeth configured for spanwise sliding engagement with a second plurality of teeth on the at least one flap.

[0012] In some embodiments, the at least one flap is placeable at a plurality of different angles of attack.

[0013] In some embodiments, the blade body includes one or more sockets and the at least one flap includes one or more shoulders respectively configured for engagement with the one or more sockets.

[0014] In some embodiments, the at least one flap includes a bulb and the blade body includes a socket configured for slidably receiving the bulb. In some embodiments, the bulb and the socket include a complementary shape that is not round to prevent rotation of the at least one flap about a spanwise pitch axis. In some embodiments, the complementary shape is selected from oval, elliptical, and polygonal. In some embodiments, the complementary shape is polygonal and includes a plurality of sides of equal dimensions to permit the at least one flap to be placed in a plurality of positions with respect to the blade body.

[0015] In some embodiments, a variety of different flaps are interchangeably insertable into the complementary connection structure of the blade body, wherein each of the flaps has at least one characteristic that is different from the other flaps. In some embodiments, the at least one characteristic is selected from airfoil shape, chord length, span, camber, angle of attack, planform area, aspect ratio, and a combination thereof. In some embodiments, each of the flaps is configured for substitution for a previously installed flap without having to remove an associated fan blade from the hub.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Fig. 1 is a perspective view of a fan having a plurality of blades.

[0017] Fig. 2 is a perspective view of a blade of the fan of Fig. 1.

[0018] Fig. 3 is a side view of a first embodiment of a blade body.

[0019] Fig. 4 is a side view of a first embodiment of an adjustable flap configured for assembly with the blade body of Fig. 3.

[0020] Fig. 5 is a side view of the blade body of Fig. 3 assembled with the adjustable flap of Fig. 4, wherein the adjustable flap is shown in a first (up) position.

[0021] Fig. 6 is a side view of the blade body of Fig. 3 assembled with the adjustable flap of Fig. 4, wherein the adjustable flap is shown in a second (down) position.

[0022] Fig. 7 is a schematic side view of the blade body of Fig. 3 assembled with the adjustable flap of Fig. 4, wherein the adjustable flap is shown in both the first (up) position and the second (down) position to illustrate the different angle of attack associated with each position.

[0023] Fig. 8 is a side view of a second embodiment of a blade body. [0024] Fig. 9 is a side view of the blade body of Fig. 8 assembled with a second embodiment of an adjustable flap, wherein the adjustable flap is shown in a first (up) position.

[0025] Fig. 10 is a side view of the blade body and adjustable flap of Fig. 9, wherein the adjustable flap is shown in a second (mid) position.

[0026] Fig. 11 is a schematic side view of the blade body and adjustable flap of Fig. 9, wherein the adjustable flap is shown in both the first (up) position and the second (mid) position.

[0027] Fig. 12 is a side view of the blade body and adjustable flap of Fig. 9, wherein the adjustable flap is shown in a third (down) position.

[0028] Fig. 13 is a schematic side view of the blade body and adjustable flap of Fig. 9, wherein the adjustable flap is shown in both the first (up) position and the third (down) position.

[0029] Fig. 14 is a side view of a third embodiment of a blade body.

[0030] Fig. 15 is a side view of a third embodiment of an adjustable flap configured for assembly with the blade body of Fig. 14.

[0031] Fig. 16 is a side view of a fourth embodiment of a blade body.

[0032] Fig. 17 is a side view of a fourth embodiment of an adjustable flap configured for assembly with the blade body of Fig. 16.

[0033] Fig. 18 is a side view of the blade body of Fig. 16 assembled with the adjustable flap of Fig. 17, wherein the adjustable flap is shown in a first (up) position.

[0034] Fig. 19 is a side view of the blade body of Fig. 16 assembled with the adjustable flap of Fig. 17, wherein the adjustable flap is shown in a second (down) position.

[0035] Fig. 20 is a side view of a fifth embodiment of a blade body, an inboard flap, and an outboard flap. [0036] Fig. 21 is a side view of the outboard flap of Fig. 20.

[0037] Fig. 22 is a side view of the inboard flap of Fig. 20.

DETAILED DESCRIPTION

[0038] As used herein, the following terms should be understood to have the indicated meanings:

[0039] When an item is introduced by “a” or “an,” it should be understood to mean one or more of that item.

[0040] “Comprises” means includes but is not limited to.

[0041] “Comprising” means including but not limited to.

[0042] “Having” means including but not limited to.

[0043] As shown in Fig. 1, a fan 10 may have a plurality of blades 12 connected to a hub 14. Fan 10 may have a motor (not shown) configured to rotate hub 14 and thereby cause the blades 12 to create an airflow. As shown in Fig. 2, each blade 12 may include a blade body 16 and at least one flap connected to the blade body 16. For example, blade 12 may have an inboard flap 20 and an outboard flap 18. In some embodiments, inboard flap 20 and outboard flap 18 may abut one another at an interface 22. In some embodiments, adjacent flaps may or may not abut one another. Inboard flap 20 may have one or more characteristics (e.g., airfoil shape, chord length, span, camber, angle of attack, planform area, aspect ratio, etc.) that are the same or different from outboard flap 18. For example, if increased airflow in the inboard region is desired, inboard flap 20 may have a chord length Ci that is greater than the chord length C₀ of outboard flap 18, and/or inboard flap 20 may be configured at a greater angle of attack than outboard flap 18, as described further below. Inboard flap 20 may have a span Si that is the same, shorter, or longer than the span S₀ of outboard flap 18.

In some embodiments, either or both of inboard flap 20 and outboard flap 18 may include a transition portion in the vicinity of the interface between the two flaps. For example, as shown in Fig. 2, inboard flap 20 may include an adjoining portion 24 and a transition portion 26 to smoothly transition from the shorter chord length C₀ of outboard flap 18 to the longer chord length Ci of inboard flap 20. Of course, any suitable shapes may be employed, depending on the desired airflow characteristics.

[0044] To help facilitate the assembly and adjustment of the one or more flaps 18, 20 with respect to the blade body 16, the blade body 16 and flaps 18, 20 may be configured with complementary connection structures whereby the flaps 18, 20 may be slidably engaged with the blade body 16 in a generally spanwise direction but otherwise substantially fixed in relation to the blade body 16. In some embodiments, the complementary connection structures may allow the flaps 18, 20 to be placed in a plurality of positions (e.g., pitch positions about a generally spanwise axis As) with respect to the blade body 16. For example, in some embodiments, inboard flap 20 and outboard flap 18 may have substantially the same connection structure for sliding engagement with the blade body 16, and the inboard flap 20 may be placed in a first orientation with respect to the blade body 16 and the outboard flap 18 may be placed in a second orientation with respect to the blade body 16.

[0045] For example, referring to Figs. 3-7, a first embodiment is shown in which the blade body 16A has a curved leading edge 28, an upper surface 34, a lower surface 36, and an open, female-type connection structure at its trailing edge that may include a plurality of protrusions 40, 42, 44 extending rearwardly from a wall 38, and a plurality of bearing surfaces 54, 56, 58, 60. In some embodiments, blade body 16A may include one or more stiffeners 30, 32 depending inwardly from the upper surface 34 and/or the lower surface 36 of the blade body 16A, which may help minimize warping due to heat, for example. The protrusions 40, 42, 44 may define a plurality of grooves 46, 48 configured to slidingly and removably receive a tongue 62 provided on the leading edge of a flap (e.g., outboard flap 18 or inboard flap 20). For the sake of simplicity, a first embodiment of an inboard flap 20A is illustrated, but it will be understood that an outboard flap may be similarly configured.

[0046] Flap 20A may have a body 76, a trailing edge 78, and a male-type connection structure at its leading edge configured for spanwise sliding engagement with the female-type connection structure of blade body 16A. The bearing surfaces 54, 56, 58, 60 of blade body 16A may be configured for spanwise sliding engagement with complementarily shaped bearing surfaces 68, 70, 72, 74, respectively, of flap 20A. In some embodiments, bearing surfaces 68, 70 may be provided on arms 80, 82, respectively, which may cooperate with bearing surfaces 54, 56 of corresponding arms 150, 152 on blade body 16A to removably capture flap 20A with respect to blade body 16A. The respective connection structures of blade body 16A and flap 20A may be sized and shaped to permit placement of flap 20A in two different positions with respect to blade body 16A: an “up” position as shown in Fig. 5, and a “down” position as shown in Fig. 6. In the “up” position, edge 66 of arm 82 may be engaged with a stop 52 of blade body 16A, and tongue 62 of flap 20A may be disposed in groove 48 of blade body 16A. In the “down” position, edge 64 of arm 80 may be engaged with a stop 50 of blade body 16A, and tongue 62 of flap 20A may be disposed in groove 46 of blade body 16A. In either position, the cooperating connection structures of blade body 16A and flap 20A serve to hold flap 20A in place on blade body 16A while permitting spanwise sliding engagement and disengagement of flap 20A and blade body 16A.

[0047] Both the “up” and “down” positions are illustrated in Fig. 7. As shown, the adjustability of flap 20A with respect to blade body 16A allows placement of flap 20A at a first angle of attack Ai in the “up” position and a second angle of attack A2 in the “down” position. Trailing edge 78 of flap 20A may be placed in an up position 78u and a down position 78d, respectively. Although two positions are illustrated in this embodiment, it will be understood that more than two positions may be enabled by providing additional grooves in blade body 16A in which tongue 62 of flap 20A may be disposed.

[0048] Referring to Figs. 8-13, a second embodiment is illustrated in which a blade body 16B and flap 20B may be configured for spanwise sliding engagement similar to blade body 16A and flap 20A described above except that instead of a tongue-and-groove connection this second embodiment provides a toothed connection between blade body 16B and flap 20B. For example, a plurality of teeth 86 may be provided on a curved wall 84 of blade body 16B for spanwise sliding engagement with a plurality of teeth 88 on flap 20B. In this embodiment, the plurality of teeth 86, 88 engaged at different angles serve to keep flap 20B in place on blade body 16B. Such a toothed connection may permit placement of flap 20B in a plurality of positions with respect to blade body 16B, such as “up,” “mid,” and “down” positions as illustrated in Figs. 9, 10, and 12, respectively (trailing edge 78 of flap 20B is shown in positions 78u, 78m, and 78d positions, respectively). The “up” and “mid” positions are shown in Fig. 11, and the “up” and “down” positions are shown in Fig. 13.

Thus, in this embodiment, flap 20B may be placed at a plurality of different angles of attack using the same connection structure. In the “up” position, flap 20B may be substantially engaged with blade body 16B at interface 90 as shown in Fig. 9, and a gap 92 may exist in that region in the “mid” and “down” positions as shown in Figs. 10 and 12, respectively.

[0049] Referring to Figs. 14-15, a third embodiment is illustrated in which a blade body 16C and flap 20C may be configured for spanwise sliding engagement similar to blade body 16A and flap 20A described above except that instead of a single tongue-and-groove and arm-capture connection this third embodiment provides a double tongue-and-groove and wedge connection between blade body 16C and flap 20C. For example, blade body 16C may include a plurality of grooves 116, 118, 120 defined by the upper and lower walls 158, 160 of a wedge-shaped cavity 154 and protrusions 98, 100 extending from a wall 96. The grooves 116, 118, 120 may be configured for receiving tongues 112, 114 of flap 20C, and groove 102 of flap 20C may be configured for receiving protrusions 98, 100 of blade body 16C. Flap 20C may include a wedge-shaped arm 156 from which tongues 112 and 114 depend and bearing surfaces 108, 110 configured for engagement with complementary bearing surfaces 104, 106 of blade body 16C. Flap 20C may be placed in an “up” position in which tongues 112, 114 are engaged with grooves 118, 120, respectively, protrusion 100 is engaged with groove 102, and surface 164 of arm 156 is engaged with surface 160 of blade body 16C. Flap 20C may be placed in a “down” position in which tongues 112, 114 are engaged with grooves 116, 118, respectively, protrusion 98 is engaged with groove 102, and surface 162 of arm 156 is engaged with surface 158 of blade body 16C.

[0050] Referring to Figs. 16-19, a fourth embodiment is illustrated in which a blade body 16D and flap 20D may be configured for spanwise sliding engagement similar to blade body 16C and flap 20C described above except that this fourth embodiment includes additional tongue-and-groove features. For example, blade body 16D may include tongues 142, 144 configured for engagement in grooves 130, 132, respectively, of flap 20D. Tongues 142, 144 and grooves 130, 132 may be sized and shaped to permit placement of flap 20D in an “up” position as shown in Fig. 18 and a “down” position as shown in Fig. 19. In the “up” position, tongues 112, 114 are engaged with grooves 118, 120, respectively, protrusion 100 is engaged with groove 102, and surface 128 of arm 156 is engaged with surface 124 of blade body 16D. In the “down” position, tongues 112, 114 are engaged with grooves 116, 118, respectively, protrusion 98 is engaged with groove 102, and surface 126 of arm 156 is engaged with surface 122 of blade body 16D. Flap 20D may include shoulders 134, 136 configured for engagement with sockets 138, 140, respectively, of blade body 16D.

[0051] Referring to Figs. 20-22, a fifth embodiment is illustrated in which an outboard flap 18E and an inboard flap 20E may be configured for spanwise sliding engagement with a blade body 16E. Blade body 16E may include a socket 146 configured for slidably receiving a bulb 148 provided on flap 18E and flap 20E. Socket 146 and bulb 148 may be complementary in shape. In some embodiments, socket 146 and bulb 148 may have a shape that is not round (e.g., oval, elliptical, polygonal, or other suitable shape) to prevent rotation of flap 18E or flap 20E about a spanwise pitch axis. In some embodiments, socket 146 and bulb 148 may have a shape that permits flap 18E and/or flap 20E to be placed in a plurality of positions with respect to blade body 16E. For example, socket 146 and bulb 148 may have a generally polygonal shape with a plurality of sides of equal dimensions (e.g., hexagonal, octagonal, decagonal, dodecagonal, or the like). Of course, any suitable shape may be employed.

[0052] Fan blades and flaps as described herein may also create further versatility.

For example, in some embodiments, a given blade body having a certain connection structure may be compatible with a variety of different flaps that have a complementary connection structure but different characteristics in other aspects. For example, a variety of different flaps may be interchangeably insertable into the complementary connection structure of a given blade body, wherein each flap has at least one characteristic that is different from the other flaps in the group of flaps, such as airfoil shape, chord length, span, camber, angle of attack, planform area, aspect ratio, or a combination thereof. So, for example, one or more flaps may be selected for installation on a blade body to achieve certain desired airflow characteristics, and if the airflow needs change, one or more other flaps may be substituted for the originally installed flaps without having to remove the fan blade from the hub. Similarly, a variety of flaps having different aesthetic appearances may be compatible with a given blade body, so the appearance of the fan blades and thus the overall fan on which they are installed may be readily changed. [0053] Although two flaps (inboard and outboard) have been illustrated herein, persons of ordinary skill in the art will appreciate that only one flap or more than two flaps may be used, depending on the desired airflow characteristics. Likewise, although it is envisioned that blade bodies and flaps as described herein may be made using extrusion manufacturing processes, persons of ordinary skill in the art will understand that any suitable manufacturing processes may be used. Also, although some embodiments described herein are envisioned primarily for ceiling fans, it will be appreciated that fan blades and flaps as described herein may be used for other types of fans, such as ventilation and exhaust fans, for example.

[0054] Although the foregoing specific details describe certain embodiments of this invention, persons of ordinary skill in the art will recognize that various changes may be made in the details of this invention without departing from the spirit and scope of the invention as defined in the appended claims and other claims that may be drawn to this invention and considering the doctrine of equivalents. Among other things, any feature described for one embodiment may be used in any other embodiment, and any feature described herein may be used independently or in combination with other features. Also, unless the context indicates otherwise, it should be understood that when a component is described herein as being mounted or connected to another component, such mounting or connection may be direct with no intermediate components or indirect with one or more intermediate components. Therefore, it should be understood that this invention is not to be limited to the specific details shown and described herein.

Claims

CLAIMS WHAT IS CLAIMED IS:

1. A fan comprising: a hub; a plurality of blades attached to the hub; and a motor configured to rotate the hub; wherein each of the plurality of blades comprises: a blade body; and at least one flap slidably and removably engaged with the blade body in a generally spanwise direction; wherein the at least one flap is configurable in a plurality of pitch positions about a generally spanwise axis.

2. The fan of claim 1 wherein the at least one flap comprises an inboard flap and an outboard flap.

3. The fan of claim 2 wherein the inboard flap comprises one or more characteristics that are the same as the outboard flap.

4. The fan of claim 3 wherein the one or more characteristics are selected from airfoil shape, chord length, span, camber, angle of attack, planform area, aspect ratio, and a combination thereof.

5. The fan of claim 2 wherein the inboard flap comprises one or more characteristics that are different from the outboard flap.

6. The fan of claim 5 wherein the one or more characteristics are selected from airfoil shape, chord length, span, camber, angle of attack, planform area, aspect ratio, and a combination thereof.

7. The fan of claim 5 wherein the inboard flap has a chord length Ci that is greater than a chord length C₀ of the outboard flap.

8. The fan of claim 5 wherein the inboard flap is configured at a greater angle of attack than the outboard flap.

9. The fan of claim 2 wherein at least one of the inboard flap and the outboard flap includes a transition portion in the vicinity of an interface between the inboard flap and the outboard flap.

10. The fan of claim 1 wherein the blade body and the at least one flap are configured with complementary connection structures whereby the at least one flap is slidably engaged with the blade body in a generally spanwise direction but otherwise substantially fixed in relation to the blade body.

11. The fan of claim 10 wherein: the at least one flap comprises an inboard flap and an outboard flap; and the inboard flap is placeable in a first orientation with respect to the blade body and the outboard flap is placeable in a second orientation with respect to the blade body.

12. The fan of claim 10 wherein the complementary connection structures comprise a tongue-in-groove connection.

13. The fan of claim 12 wherein: the at least one flap includes a leading edge having a tongue; and the blade body includes a trailing edge having a plurality of protrusions extending rearwardly from a wall, wherein the plurality of protrusions define a plurality of grooves configured to slidingly and removably receive the tongue.

14. The fan of claim 12 wherein the complementary connection structures further comprise complementarily shaped bearing surfaces configured for spanwise sliding engagement with each other.

15. The fan of claim 10 wherein the at least one flap is adjustable for placement at a first angle of attack and a second angle of attack.

16. The fan of claim 10 wherein the complementary connection structures comprise a toothed connection wherein the blade body includes a first plurality of teeth configured for spanwise sliding engagement with a second plurality of teeth on the at least one flap.

17. The fan of claim 16 wherein the at least one flap is placeable at a plurality of different angles of attack.

18. The fan of claim 10 wherein the blade body includes one or more sockets and the at least one flap includes one or more shoulders respectively configured for engagement with the one or more sockets.

19. The fan of claim 10 wherein the at least one flap includes a bulb and the blade body includes a socket configured for slidably receiving the bulb.

20. The fan of claim 19 wherein the bulb and the socket comprise a complementary shape that is not round to prevent rotation of the at least one flap about a spanwise pitch axis.

21. The fan of claim 20 wherein the complementary shape is selected from oval, elliptical, and polygonal.

22. The fan of claim 21 wherein the complementary shape is polygonal and includes a plurality of sides of equal dimensions to permit the at least one flap to be placed in a plurality of positions with respect to the blade body.

23. The fan of claim 10 wherein a variety of different flaps are interchangeably insertable into the complementary connection structure of the blade body, wherein each of the flaps has at least one characteristic that is different from the other flaps.

24. The fan of claim 23 wherein the at least one characteristic is selected from airfoil shape, chord length, span, camber, angle of attack, planform area, aspect ratio, and a combination thereof.

25. The fan of claim 23 wherein each of the flaps is configured for substitution for a previously installed flap without having to remove an associated fan blade from the hub.

26. A fan blade as recited in any of the foregoing claims.

27. A fan blade body as recited in any of the foregoing claims.

28. A fan blade flap as recited in any of the foregoing claims.