Patent Publication Number: US-2021190081-A1

Title: Ceiling fan blade and grommet

Description:
CROSS-REFERENCE TO RELATED MATTERS 
     This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/952,763, filed on Dec. 23, 2019, which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF INVENTION 
     This disclosure relates to the field of ceiling fans, and more specifically, to vibration dampening in ceiling fans. The disclosure is directed to a grommet utilized in a ceiling fan blade to dampen vibrations, as well as a design for the grommet that improves ease of installation. 
     BACKGROUND OF THE INVENTION 
     Ceiling fans often include a set of blades rotatably coupled to a motor assembly to rotate the set of blades. Rotation of the set of blades drives a volume of fluid, typically ambient air within a room, space, or area. Ceiling fan blades include a traditional aesthetic, commonly having a flat bottom on the blade which provides consumers with a traditional ceiling fan style and look. 
     Traditional style blades can use a grommet element when coupling the blade to the blade iron to dampen any vibration at the connection, reducing the instance of noise or blade imbalance. However, these grommets include an annular lip at either end to secure the grommet within the mounting hole on the blade. As blade shapes change in order to improve efficiency, blade thickness and geometry changes as well, requiring larger or longer grommets. These larger or longer grommets are often difficult for the user to install due to the annular lip, as compression of the grommet for installation can be challenging. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one aspect, the disclosure relates to a ceiling fan assembly comprising: a motor including a rotor rotatably driven by the motor; a blade including a top surface and a bottom surface, with a mount hole extending between the top surface and the bottom surface; a blade iron connecting the blade to the rotor; and a grommet provided in the mount hole and including a first end and a second end, with a set of flanges including multiple discrete flanges extending from at least one of the first end or the second end. 
     In another aspect, the disclosure relates to a grommet for a ceiling fan blade, the grommet comprising: a cylindrical body extending between a first end and a second end, the cylindrical body including an exterior surface and an interior surface, with the interior surface defining an interior extending between the first end and the second end; and a set of flanges including multiple discrete flanges extending radially from the first end, relative to the cylindrical body. 
     In yet another aspect, the disclosure relates to a method of installing a ceiling fan with a grommet having a first end and a second end, with multiple discrete flanges extending from the first end and the second end, the method comprising: inserting a grommet into a mount hole of a ceiling fan blade, until the multiple discrete flanges at the first end abut a first surface of the blade and the multiple discrete flanges at the second end abut a second surface of the blade. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a partial schematic view of a ceiling fan having a set of blades suspended from a structure. 
         FIG. 2  is a perspective view of one ceiling fan blade of the set of blades of  FIG. 1 , with the blade including a set of grommets. 
         FIG. 3  is a perspective view of one grommet of the set of grommets of  FIG. 2 . 
         FIG. 4  is a top-down view of the grommet of  FIG. 3 . 
         FIG. 5  is a section view of the grommet of  FIG. 4 , taken across section V-V. 
         FIG. 6  is an exploded view of a ceiling fan assembly, showing the connection between a motor assembly, a blade iron, a blade, the set of grommets of  FIG. 2 , and a set of fasteners. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     The disclosure provided herein relates to blades for a ceiling fan, and more specifically, to a grommet used with ceiling fan blades where the blades mount to a blade iron. This disclosure also relates to the use of a grommet at the mechanical connection between a ceiling fan blade and a ceiling fan blade iron that dampens vibration from the blades as well as provides for simplified user installation of the grommet, as well as the blades and blade irons, providing for an improved overall installation experience. 
     All directional references (e.g., radial, axial, proximal, distal, upper, lower, upward, downward, left, right, lateral, front, back, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, upstream, downstream, forward, aft, etc.) are only used for identification purposes to aid the reader&#39;s understanding of the present disclosure, and do not create limitations, particularly as to the position, orientation, or use of aspects of the disclosure described herein. Connection references (e.g., attached, coupled, connected, and joined) are to be construed broadly and can include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to one another. The exemplary drawings are for purposes of illustration only and the dimensions, positions, order and relative sizes reflected in the drawings attached hereto can vary. As used herein, the term “set” or a “set” of elements can be any number of elements, including only one. For example, a set of grommets or a set of blades as used herein can include one or more grommets, or one or more blades. 
     Referring to  FIG. 1 , an exemplary ceiling fan  10  is mounted to a ceiling  12  of a structure  14 , such as in a residential home. Alternatively, the ceiling fan  10  can be mounted or suspended in a myriad of environments, such as on a ceiling or wall, in a residential space or home, outdoor or indoor, in an industrial setting, such as a manufacturing plant, or in an agricultural setting, in non-limiting examples. 
     The ceiling fan  10  includes a mount  16  suspending the ceiling fan  10  from and coupling the ceiling fan  10  to the ceiling  12 . A canopy  18  covers the mount  16 . A downrod  20  is suspended from the mount  16  by a ball  22 . A motor adapter  24  secure the downrod  20  to a motor  26  via a motor shaft  28  extending from the motor  26 . The motor  26  can include a stator  30  mounted to the motor shaft  28 , as well as a rotor  32  rotatably driven about the stator  30 . The motor adapter  24  can further couple to a motor housing  34  at least partially encasing the motor  26 . A set of blade irons  36  couples a complementary set of blades  38  to the rotor  32  for rotating the blades  38  and driving a volume of fluid, such as air, about the structure  14  or a local room therein. A switch housing  48  can mount below the motor housing  34  and electrically couple to the motor  26 . A light kit  46  can electrically and mechanically couple to the switch housing  48 . 
     It should be understood that the ceiling fan  10  as depicted in  FIG. 1  is by way of example only, and it should be understood that more or less components than those shown and described can be included with the ceiling fan  10 , and such variation among ceiling fan assemblies is within the scope of this description. 
     The ceiling fan  10  can be coupled to a power supply  40 , such as a building electrical supply. The power supply  40  may be connected to one or more controllers  42  or switches  44 . The controllers  42  can be used to receive or send information related to the control and operation of the ceiling fan  10 , such as over a wired or wireless signal. The switches  44 , can be operated to control the ceiling fan  10 , such as a wall-mounted switch, for example. While the controller  42  and the switch  44  are schematically shown exterior of the ceiling  12 , it should be appreciated that the controller  42  and the switch  44  may be optional, or may be provided in other positions, such as on the wall or ceiling, or within portions of the ceiling fan  10  itself. 
     Turning to  FIG. 2 , the blade  38  can extend between a root  60  and a tip  62 , defining a spanwise direction therebetween. The blade  38  can further include a first edge  64  and a second edge  66 , defining a chordwise direction therebetween. In one example, the first edge  64  can be a leading edge and the second edge  66  can be a trailing edge, while the particular orientation may be dependent on the rotational direction of the ceiling fan. Additionally, the blade  38  can include a top surface  68  and a bottom surface  70 , defining a thickness for the blade between the top surface  68  and the bottom surface  70 . In one non-limiting example, the bottom surface  70  can be flat, while the top surface  68  can be curved or arcuate, thereby defining an airfoil cross-sectional profile for at least a portion of the blade  38 . As is appreciable, the top surface  68  includes a convex curvature, defining an increased thickness nearer to the chordwise center of the blade  38 , as compared to the thickness at the edges  64 ,  66 . It should also be appreciated that the thickness need not be at the chord-wise center, but can vary between the first and second edges  64 ,  66 , such that the thickest portion may be nearer to one of the first edge  64  or the second edge  66 , as opposed to the chordwise center. The blade  38  can further include a set of fastener openings  72 , shown with a grommet  82  provided in each opening  72 . 
     The blade  38  can couple to the blade iron  36  by a set of fasteners  80 , which can pass through the set of fastener openings  72  and the grommets  82 . The set of grommets  82  can be included with the set of fasteners  80 , such that one grommet  82  of the set of grommets  82  can be paired with one fastener  80  of the set of fasteners  80 . Thus, the number of fasteners  80  can be complementary to the number of grommets  82 . The grommets  82  can be provided between the fasteners  80  and the body of the blade  38 , while positioned within the set of fastener openings  72 . Additionally, it is contemplated that at least a portion of the grommets  82  can be provided between the blade  38  and the blade iron  36 , to reduce or minimize vibration at the junction between the blade  38  and the blade iron  36 , along with reducing or minimizing damage or stress to the blade  38  resultant from lengthy use of the ceiling fan. The grommets  82  can be made of a rubber, plastic, or polymeric material, in non-limiting examples. Preferably, the grommets  82  are made of a material that is wear resistant, while providing for dampening any vibrational forces at the junction between the blade  38  and the blade iron  36 . One example material can include polyether ether ketone (PEEK), while any suitable material may be utilized. 
     Referring to  FIG. 3 , the grommet  82  includes a body  84  extending between a first end  86  and a second end  88 . The body  84  can be substantially cylindrical, having an interior  90  extending between the first end  86  and the second end  88 , defining an interior surface  76  and an exterior surface  78 . The grommet  82  can further include a first set of flanges  92  at the first end  86  and a second set of flanges  94  at the second end  88 . As shown, each set of flanges  92 ,  94  can include four flanges, while any suitable number of flanges is contemplated, such as between two and six flanges, while more than six flanges is contemplated. Each flange  92 ,  94  of the set of flanges can be spaced from adjacent flanges by 90-degrees, relative to the cylindrical body  84 . Each flange  92 ,  94  can be similarly shaped, with each flange  92 ,  94  including a pair of concave curved sidewalls  96 , arranged on either side of a convex end wall  98 , with concave and convex being with reference to the viewing perspective. Each concave curved sidewall  96  terminates at the exterior of the cylindrical body  84 , and then continuously transitions (or with a small gap therebetween, as shown) to another curved sidewall  96  for the adjacent flange  92 ,  94 . However, it should be appreciated that it is contemplated that the flanges  92 ,  94  need not be shaped as shown, but can be any suitable shape such that the flanges  92 ,  94  extend beyond the width of the cylindrical body  84  or the exterior surface  78  thereof. The flanges  92 ,  94  can each include a flat bottom surface  100 , configured to rest against the top or bottom surfaces  68 ,  70  of the blade  38  (see  FIG. 2 ). 
     Referring briefly to  FIG. 4 , the top-down view of the first end  86  of the grommet  82  better shows the concave curvature for the sidewalls  96 , as well as the slight convex curvature of the end walls  98 . As can be appreciated, the curvature between the sidewalls  96  of adjacent flanges  92 ,  94  seamlessly connects, to provide a continuous surface between the adjacent sidewalls  96 , which seems to terminate flush with the exterior surface  78  of the body  84  at the junction between two adjacent sidewalls  96 . 
     Referring to  FIG. 5 , a sectional view taken across section V-V of  FIG. 4 , where a sectional view of the shape of the flanges  92 ,  94  is appreciable. Namely, the bottom surface  100  can be readily identified, extending radially outwardly from the exterior surface  78 , relative to the cylindrical body  84 . Additionally, the flanges  92 ,  94  can be seen as having a beveled surface or an angled surface  102  and an outer surface  104 , with the angled surface  102  extending from one of the first and second ends  86 ,  88  of the body  84  to the outer surface  104 . The outer surface  104  then terminates at the bottom surface  100 . As shown, the outer surface  104  can be arranged orthogonal to the bottom surface  100 , while variation on the specific geometry of the grommet  82  as shown is within the scope of this disclosure, and the particular geometry as shown is by way of example. 
     The grommets  82  as described herein provide for improved dampening at the fasteners which couple the blade to the blade iron. Traditional grommets have an annular lip, as opposed to the flanges  92 ,  94  as described herein. The annular lip on other grommets generates a cylinder stress, not only on the grommet body, but also on the annular lip. The cylinder stress is a stress distribution resultant of the rotational symmetry of the grommet as well as with the annular lip for grommets that have an annular lip, and is often referred to as a circumferential stress or a hoop stress, which is defined as a normal stress in the tangential direction, relative to the cylindrical annular lip and the cylindrical body. Thus, it should be appreciated that a grommet  82  using the flanges  92 ,  94  provides for a reduced hoop stress at the flanges (where other grommets can include the annular lip), which provides for improved compressibility and ease for installing the grommet to a fan blade. 
     However, a blade that does not have flat top and bottom surfaces requires an increased height for the grommet, resulting in more required material for the grommet. The greater material provides a greater cylinder stress when installing the grommet, which makes installation of the grommet difficult. The flanges  92 ,  94  provide for improved or increased compressibility of the whole grommet, as compared to a grommet having a full annular lip, which results in a decreased cylinder stress or hoop stress, facilitating and easing installation by the user. This is particularly advantageous with aerodynamically shaped or aerodynamically efficient blades, where larger or longer grommets are required. Such larger or longer grommets are difficult to compress for installation, particularly with an annular lip. Utilizing the grommet with the flanges  92 ,  94  as described herein reduces the hoop stress to improve compressibility and ease of installation. Additionally, use of the flanges as opposed to an annular lip can provide for reduced overall material as compared with that of a grommet using an annular lip, also decreasing cost of the material. Such an overall reduction in material can even be seen when the grommet  82  is lengthened, as compared to a shorter grommet with an annular lip. In one example, use of the flanges as opposed to annular lips can provide a 6.41% decrease in overall material, while as much as a 10% decrease or more is contemplated. 
     The use of flanges as described herein provides for improved compressibility of the grommet  82 , which provides for easier installation into mount holes of the ceiling fan blade  38  by compressing the grommet  82  and inserting it into the mount holes. Thus, installation becomes easier for the user or installer, as the use of flanges permits easy compression of the grommet and insertion into the holes on the blades. Thus, the grommet as described herein provides for easier installation, decreased material usage, and decreased costs, while still providing all of the benefits of a traditional grommet in such a position. 
     Referring now to  FIG. 6 , a method of installation can be appreciated. The method can include inserting one or more grommets  110  into mount holes  112  provided in a ceiling fan blade  114 . Such insertion can be done by the user or installer on site, while it is contemplated that insertion of the grommet  110  can be done by the manufacturer. Insertion of the grommet  110  can include compressing the grommet  110 , such as by the user squeezing the grommet  110  by hand or with a tool, and inserting one end with one set of flanges  116  through the mount hole  112 . The flanges  116  provided on the grommets  110  provide for improved or increased compression of the grommets  110  during insertion into the mount holes  112 , which facilitates installation. It should be appreciated that the outer diameter of the flanges  116  is greater than that of the diameter of the mount holes  112 . Thus, compression of the flanges  116  is required for insertion of the grommet  110  into the mount holes  112 . Thus, it should be understood that the flanges  116  provide for securing the grommet against the top and bottom surfaces of the blade  114 , while providing for ease of compression during installation, particularly in comparison to that of a grommet that includes a fully annular flange. Additionally, the flanges  116  can provide for a better hold along a curved surface, as opposed to an annular lip. 
     After the grommets  110  are inserted, one or more fasteners  118  can be inserted through the grommets  110  and can fasten to a blade iron  120  via a threaded connection, for example. The grommets  110  help to dampen the connection between the blade  114  and the blade iron  120 , which reduces vibrations and noise, as well as improves operational lifetime. 
     The blade iron  120  can then be fastened to a rotor  122  via additional fasteners  124 , while any suitable connection of the blade iron  120  to the rotor  122  is contemplated, and may vary depending on the particular ceiling fan or blade iron style. Additionally, rotor  122  can be any rotational portion of the motor for the ceiling fan, and need not by a traditional rotor  122  directly driven by a stator, but can be a rotating portion of the motor housing or a mount hub, for example. 
     It should be appreciated that the method as described herein is non-limiting, and the order as discussed in regards to  FIG. 6  can be rearranged in any suitable order. For example, the blade iron  120  can attach to the rotor  122 , then attach the blade  114  to the blade iron  120 . Thus, it should be appreciated that the order of the method is non-limiting as described, and that the order may be switch or rearranged as desired. However, it is noted that it would be difficult to install the grommet  110  after the fastener  118  has been used to fasten the blade  114  to the blade iron  120 . 
     Additionally, it should be contemplated that a method of installing a ceiling fan with a grommet  82  having a first end  86  and a second end  88 , with multiple flanges  92 ,  94  extending from the first end  86  and the second end  88 . The method can include inserting a grommet into a mount hole of a ceiling fan blade, until the flanges at the first end abut a first surface of the blade and the multiple flanges at the second end abut a second surface of the blade. The method can further include wherein inserting the grommet includes compressing the grommet. The method can also further include inserting a fastener through the grommet and coupling the fastener to a blade iron to couple the ceiling fan blade to the ceiling fan. The method can also further include fastening the blade iron to the ceiling fan. 
     To the extent not already described, the different features and structures of the various aspects can be used in combination, or in substitution with each other as desired. That one feature is not illustrated in all of the examples is not meant to be construed that it cannot be so illustrated, but is done for brevity of description. Thus, the various features of the different aspects can be mixed and matched as desired to form new aspects, whether or not the new aspects are expressly described. All combinations or permutations of features described herein are covered by this disclosure. Therefore, it should be understood that it is contemplated that features of one embodiment may be applied to another embodiment, and interchanged, added, or removed to form additional embodiments not explicitly shown, but still within the scope of the disclosure. 
     Although the embodiment of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.