Patent Publication Number: US-6210117-B1

Title: Device for connecting a fan blade to a rotor of a ceiling fan motor

Description:
This invention relates to ceiling fans, and in particular to devices for easily connecting blade mounting arms to the rotors on ceiling fan motors using captive fasteners and alignment posts. 
     BACKGROUND AND PRIOR ART 
     FIG. 1 shows a partial side view of a conventional ceiling fan unit  1  that encompasses a general prior art ceiling fan system. In FIG. 1, ceiling fan motor  10  has a rotor component  20  that rotates about a central axis beneath motor  10 , which is in turn connected to a housing  5  that is attached beneath a ceiling  2 . A plurality of fan blades  30  are connected to the rotor  20  by mounting arms  40 . Each mounting arm  40  has one end  42  connected to an end  32  of each fan blade  30 , and a second end  44  having at least two through-holes  45  therethrough, so that conventional fasteners such as screws  50  pass through the through-holes  45  to mateably thread into threaded holes  25  in the bottom of rotor  20 . 
     Usually most conventional directions have the installer first connect and hang the motor  10 , rotor  20  and housing  5  to a ceiling. More often than not the installer is usually perched on a stool or ladder. Next, many directions have the installer attach the fan blades  30  to their respective mounting arms  40 . Finally, one of the last steps is to connect the blade  30  and respective mounting arm  40  to the rotor  20  on the motor. 
     To finish this final assembly step takes great dexterity, patience, balance and time. In order for a single person  60  to be able to complete this final step, the installer  60  needs to hold in one hand  62  the fan blade  30  and already attached mounting arm  40 , and to position a screw driver  70  to the heads of screws  50  with the other hand  64 . The installer must be able to balance the mounting screws  50  on the tip of the screw driver  70 , insert the screws upwardly though the holes  44  in the mounting arm, making sure not to accidentally drop the screws  50  and then screw the screws  50  into the mating holes  25  on the rotor  20  all while still holding the blade  30  and arm  40 . 
     This assembly requires the installer to have to constantly hold both hands  62  and  64  raised high above their head, while again standing on a stool or ladder. 
     Many problems occur from this traditional method of having one person installing a ceiling fan. Screws  50  can and do accidentally fall and become lost causing more time and more expense to finish the installation. The installer  60  often has to constantly re position the blade  30  and arm  40  in order to be able to properly line up the through-holes  42  in the mounting arms  40  with their respective mating holes  25  in the bottom of rotor  20 . The blade  30  and mounting arm  40  have been known to fall on and cause injury to the user  60  during assembly. Additionally, the user can lose their balance and injure themselves as well falling off the ladder and stool. Additional problems also occur after installation. For example, uneven tightening of each of the plural fasteners that connect the mounting arm to the motor has resulted in wobble effects when the ceiling fan system is running. Thus, the current operation of assembly has become known as a frustrating, undesirable, difficult, tedious, time consuming and sometimes dangerous task. 
     To merely add a second worker to help in the assembly installation may solve some of the problems above, but would add additional cost and labor expense to the installation project. 
     SUMMARY OF THE INVENTION 
     The first objective of the present invention is to provide a device to allow a single user to safely and easily attach a fan blade mounting arm to a ceiling mounted fan motor. 
     The second object of this invention is to provide a device for attaching a fan blade mounting arm to a ceiling fan motor that eliminates losing fasteners such as screws. 
     The third object of this invention is to provide a device for attaching a fan blade mounting arm to a ceiling fan motor by holding fasteners captive in the blade mounting arm. 
     The fourth object of this invention is to provide a device for guiding a fan blade mounting arm onto a ceiling mounted motor. 
     The fifth object of this invention is to provide a device for aligning a fan blade mounting arm to a ceiling fan mounted motor. 
     The sixth object of this invention is to evenly attach all the fasteners that connect a ceiling fan blade to a ceiling mounted motor to eliminate wobble effects when running the ceiling fan. 
     A first preferred embodiment of the novel invention device for attaching ceiling fan mounting arms to ceiling fan motors using fasteners held captive on the mounting arms, includes a ceiling fan motor having a rotating member such as a rotor endshield where the motor and rotating member have already been hung from a ceiling. A fan blade is connected to one end of a mounting arm with a second end having a captive fastener therein with a threaded end, and means such as a screw driver and the like for screwing the threaded end of the captive fastener into a mateable opening on the rotating member. The captive fastener can be the combination of a rubber type washer pre-installed within an opening in the second end of the mounting arm, and a portion of the fastener held within the opening by the washer. The fastener can have a head and a shaft, the shaft having a threaded end and an enlarged base portion between the threaded end and the head of the fastener, where the neck portion is held captive within the washer. The enlarged base portion allows plural fasteners to be evenly tightened when attaching the mounting arm to the motor. Even tightening of all the fasteners eliminates known wobbling problems when the ceiling fan is running. The washer can be a deformable member such as but not limited to a grommet shape with a first portion sandwiched between a bottom of the mounting arm and a second portion sandwiched between the rotating member and a top of the mounting arm in order to reduce any vibration noise and movement between the rotating member of the fan motor, the mounting arm and the blade. Alternately, fasteners can be held captive within the mounting arm without using separate deformable member inserts. The interior surface walls of the through-holes in the mounting arm can be narrow enough to just be able to hold captive a fastener therein. For example, the interior surface can be tapered, roughened, include protruding portions, and the like, all of which can be part of the same material that makes up the blade mounting arm. Mounting blade arms with this type of captive fastener can be made of materials such as but not limited to plastic, wood, and the like. 
     A second embodiment of the captive fastener has a fastener held captive in a floating position in the mounting arm through-hole. A head of the fastener can be to one side of a ledge in a through-hole within the mounting arm. The threaded end of the fastener can have a larger diameter than a narrow neck portion of the fastener so that the neck portion is located between the fastener head and the threaded end, and the threaded end being positioned to a second side of the ledge opposite the first side. The narrow neck of the fastener can move upward and downward a selected distance about the ledge. A tip portion of the fastener can protrude through an upper side of the mounting arm for guiding the mounting arm to the mateable opening on the rotating member. The heads of the captive fasteners in both the first and second embodiment can be like a regular headed screw, a Philips head screw and a bolt. An optional spring locking washer can help lock the tightened fastener in place. 
     When assembling both the first and second embodiments, the ceiling fan motor housing and rotating member(endshield) can usually first be hung from a ceiling. Next the installer can simply hold the pre-connected mounting arm and fan blade with one hand and guide the mounting arm until the tip portion of the captive fastener enters into the mateable threaded opening on the rotating member. With the other hand, the installer can tread the fastener into the threaded opening on the rotating member. 
     The third embodiment of the invention includes an alignment post and a mateable opening for receiving the alignment post, for allowing the mounting arm to be correctly aligned in position onto the rotating member. The post can extend upward from the mounting arm with a mateable receiving opening on the bottom of the rotating member. Alternatively, the alignment post can extend downward from the rotating member with the receiving opening on the mounting arm. The post can have tapered length with rounded sides so that pushing the post into the receiving opening snugly connects the mounting arm to the rotating member on the ceiling fan motor. Another version of the post has flat side portions such as those found in a square, rectangle, hexagon and the like, with the receiving opening having like configurations, thus creating a fixed position for connecting the mounting arm to the rotating member. Another version includes a second alignment post and a second mateable opening for receiving the second alignment post. With two alignment posts, only one captive fastener needs to be used Still another version allows the alignment posts to be used with existing non captive fasteners, such as but not limited to regular and Philips head screws, bolts, and the like. The novel alignment posts also eliminate known wobbling effects since the posts allow the mounting arms to be evenly attached to the motor. 
     Further objects and advantages of this invention will be apparent from the following detailed description of a presently preferred embodiment which is illustrated schematically in the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     FIG. 1 shows a prior art view of a blade with mounting arm attached to ceiling fan motor and rotor. 
     FIG. 2A is a perspective exploded view of a first embodiment of the fasteners, novel grommet washer, with mounting arm and rotor and ceiling fan motor components for the subject invention. 
     FIG. 2B is a side cross-sectional view of an assembled captive fastener and associated components of FIG. 2A along arrow E being finally assembled. 
     FIG. 2C is perspective view of a novel alternative fastener that can be used with the first embodiment of FIGS. 2A-2B. 
     FIG. 2D is a view of FIG. 2B showing the novel alternative fastener connecting the mounting arm to the rotating members and ceiling fan motor using the novel grommet washer. 
     FIG. 2E is another view of FIG. 2B showing another version of a fastener being held captive by being snugly held in place by the inner walls of the through-holes in the mounting arms. 
     FIG. 3A is a perspective exploded view of a second embodiment of a captive fastener and spring washer within a ceiling fan mounting arm. 
     FIG. 3B is a side cross-sectional view of two captive fasteners and spring washers of FIG. 3A being aligned with mateable holes in the motor endshield rotor of FIG. 2A 
     FIG. 3C is an enlarged side view of the unattached captive fastener of FIG.  3 B. 
     FIG. 3D is an enlarged side view of the attached captive fastener of FIG.  3 B. 
     FIG. 4A is a perspective view of a third embodiment of using either or both the captive fastener of the preceding Figures, or conventional fastener with an alignment post for attaching the mounting arm to the a ceiling fan motor. 
     FIG. 4B shows another version of an alignment post having flat side portions for use with FIG.  4 A. 
     FIG. 4C is a perspective view of the third embodiment of FIG. 4A using two alignment posts which allows for only one captive or one conventional fastener to hold the mounting arm to the motor. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Before explaining the disclosed embodiment of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation. 
     FIRST EMBODIMENT 
     FIG. 2A is a perspective exploded view of a first embodiment  100  of the fasteners  50 , novel grommet washer  101 , with mounting arm  40  rotor  20  and bottom  22  and ceiling fan motor  10  components for the subject invention. Referring to FIG. 2A, a mounting arm  40  has one end  42  connected to fan blades (not shown here, but shown more clearly in FIG. 1) and a second end  44  having through-holes  45  therethrough. A novel flexible and pliable grommet shaped washer  101  having a longitudinal planar upper portion  105  having a width and length approximately the same as the upper surface width and length of mounting arm end  44 . Two hollow cylindrical portions  110  and  120  are located in identical positions as through-holes  45  in mounting arm end  44 . Cylindrical portions  110 ,  120  have respective bottom expanding flange portions  112  and  122 . Pliable and flexible grommet shaped washer  101  can be formed from rubber, elastomers, plastics, combinations, thereof, and the like. 
     During assembly of the ceiling fan motor  10 , rotating rotor member  20  with bottom endshield  22 , has threaded hole openings  25  therein, and housing  5  can usually first be pre-hung from a ceiling  2  in a manner similar to that done in the prior art FIG. 2B is a side cross-sectional view of an assembled captive fastener  50  and associated components of FIG. 2A along arrow E being finally assembled. FIG. 2B shows a single pre-installed (captive) fastener  50  within the cylindrical portion  10  of the novel grommet washer  101  of FIG.  2 A. Referring to FIGS. 2A and 2B, the pliable and flexible cylindrical portions  110 ,  120  of the grommet washer  101  are pushed into the through-holes  45  of the mounting arm  40  in the direction of arrow A, so that the flange portions  112 ,  122  are on the opposite side of a ledge portion  46  of the mounting arm end  44  thus holding the grommet washer  101  to the mounting arm end  44 . Next, the threaded end  55  of fasteners  50  are pushed into the narrow hollow openings in pliable cylindrical portions  110 ,  120  in the direction of arrow B. The inner diameters of hollow openings  110 ,  120  can be sized slightly smaller than the exterior diameter of threaded ends  55  thus causing the threaded ends  55  to be held in place with a tip end  59  (only one is shown for clarity) exposed on the upper side of the grommet washer planar portion  105 . The regular fasteners  50  that can be used can have heads  52  such as regular head and Philips head screws, bolt heads and the like. Additionally, an extra washer  54  such as those made from steel, rubber, elastomer and the like, can be used with fasteners  50 . The grommet washer  101  allows the fasteners  50  to be held captive in the mounting arm  40  prior to attaching the mounting arm  40  to the rotating members  20 ,  22  of the ceiling mounted motor  10 . 
     Referring to FIGS. 2A,  2 B, the final step of installation can have the installer  60  (shown in FIG.  1 ), in one hand hold the blade  30  connected to mounting arm  40 , and guide the tip ends  59  of the fasteners  50  in the direction of arrow C into the mateable threaded openings  25  in bottom endshield  22  of rotating rotor  20  of motor  10 . Next the installer can screw the fasteners  50  into the endshield with a driver  70  such as a screw driver. If bolts are used as the fasteners  50 , the installer  60  can use a ratchet wrench, and the like. The dotted lines in FIG. 2B represent the final position of the rotating endshield  22  connected to threaded ends  55  of the fastener, so that pliable and flexible planar portion  105  of the grommet washer is compressed and sandwiched between the rotating endshield  22  and the mounting arm  40 . Similarly pliable and flexible bottom flange portion  112  of grommet washer  101  is compressed and sandwiched between the fastener head  52  and the mounting arm  40 . Thus, the compressed and sandwiched portions  105  and  112  of the grommet washer  101  eliminate vibration noise and movement between the fan motor  10  with rotator  20  bottom endshield  22 , and the mounting arm  40  and the fastener(s)  50 . Many fan systems use all metal rotors, endshields, fasteners and mounting arms. Using the pliable flexible novel grommet washer  101  eliminates both the inherent vibration noise between the contacting metal components and resulting looseness that can develop when metal vibrating components are directly contacting one another. 
     FIG. 2C is perspective view of a novel alternative fastener that can be used with the first embodiment  100  of FIGS. 2A-2B. FIG. 2D is a view of FIG. 2B showing the novel alternative fastener connecting the mounting arm to the rotating members and ceiling fan motor using the novel grommet washer. Referring to FIGS. 2C and 2D, alternative fastener  150  has an enlarged lower base portion  156  between the threaded shaft end  155  and the fastener head  152 . The enlarged lower base portion  156  can allow for a tighter captive fit within cylindrical portion  110  of grommet washer  101 . Using enlarged base fasteners allows for all the fasteners  150  being used to attach a mounting arm  40  to the endshield  22  to be tightened such that all upper edges  157  of these fasteners  150  abut against the lower surface of endshield  22 . The installer is able to evenly position each of the fasteners  150  between the mounting arm  40  and the endshield  22  and eliminate wobble effects if the mounting arm was unevenly mounted. Additionally, mounting arms  40  can have a second interior ledge portion  48  below the first ledge  46  thus allowing the fastener head  152  to be counter sunk below the bottom exterior surface of the blade arm end  44 . The enlarged base portion  156  of the novel fastener  150  causes a partial compression of the inner cylindrical walls of cylindrical portion  110  but still allows the installer to rotate the fastener  150  when doing the final assembly as described above. The resultant configuration shown in FIG. 2D has the upper portion  105 , cylindrical portion  110 , and bottom flange  112  of the grommet washer  101  all partially compressed allowing a tight and vibration free fit. 
     FIG. 2E is another view of FIG. 2B showing another version of a fastener  50  being held captive by being snugly held in place by the inner walls  45 ′ of the through-holes in the mounting arms  40 . The interior surface walls  45 ′ of the through-holes in the mounting arm can be narrow enough to just be able to hold captive a threaded end  55  of a fastener  50 . For example, the interior surface  45 ′ can be tapered, roughened, include protruding portions, and the like, all of which can be part of the same material that makes up the blade mounting arm. Although the preferred mounting blade arms useful with the subject invention embodiments are metal, the mounting blade arms  40  that can be used with this type of captive fastener  50  held in place only by the interior surface of the walls can be made of materials such as but not limited to plastic, wood, and the like. Similar to that described previously, the mounting arm  40  can be guided to a motor endshield threaded receiving opening  25  by the tip  59 . The installer can rotate fastener head  52  threading threaded end  55  into receiving opening  25  until head  52  abuts against inner ledge surface  46 . 
     SECOND EMBODIMENT 
     FIG. 3A is a perspective view of a novel captive fastener  250  with an optional spring locking washer  260  used for the second embodiment  200 . FIG. 3B is a side cross-sectional view of a second embodiment  200  of using two of the novel captive fasteners  250  and spring washers  260  of FIG. 3A with a mounting arm  240 , rotor  20 , and bottom endshield  22  that is connected to a ceiling fan motor  10 . FIG. 3C is an enlarged side view of the unattached fastener F 1  of FIG.  3 B. FIG. 3D is an enlarged side view of the attached fastener F 2  of FIG.  3 B. 
     Referring to FIGS. 3A-3D, the fasteners  250  are already held captive in one end of the mounting arm  240  and the opposite end of the mounting arm is already connected to a fan blade (not shown). Fasteners  250  can have a threaded end portion  255  with a diameter larger than a base neck portion  256  and a large head portion  252 . The narrow base neck portion  256  between the threaded end  255  and the head  252  allows the fastener  250  to freely float therebetween about ledge  246 ,  248 . The fasteners  250  that can be used can have heads  252  such as regular head and Philips head screws, bolt heads and the like. The blade mounting arm  240  can be similar to the mounting arm  40  of the first embodiment, but with some differences. The through holes  245  in the mounting arm  240  have an upper opening portion  247  with a first diameter sized slightly larger than the diameter of the threaded ends  255  of the novel fasteners  250 . Through-holes  245  have an interior facing ledge portion  246  with an internal facing lip portion  248 , the latter having a diameter slightly larger than the base neck portion  256  of the fasteners  250 . Finally, through-holes  245  have a lower opening portion  243  with a diameter slightly larger than the exterior diameter of the heads  252  of the fasteners  250 . An optional spring washer  260  is positioned about the base neck portion  256  and between the ledge/lip  246 ,  248  and the head  252  of the fastener in order to lock fastener  250  in place. In an unattached position shown in FIG. 3C, the fastener head  252  freely floats to a downward position based on gravity away from the mounting arm  240 , and has an end tip  259  slightly protruding upward from an upper surface of the mounting arm  240 . 
     Similar to the first embodiment, the fan motor, rotor  20  and bottom endshield  22  are first hung from a ceiling. Also similar to the first embodiment, the final step of installation for the second embodiment  200  can have the installer  60  (shown in FIG.  1 ), in one hand hold the blade  30  and pre-connected mounting arm  240 , and guide the tip ends  259  of the pre-captive fasteners  250  into the mateable threaded openings  25  in the bottom endshield  22  of rotating rotor  20  of motor  10 , and rotate the pre-captive fasteners  250  into the endshield with a driver  70  such as a screw driver. If bolts are used as the fasteners  250 , the installer  60  can use a ratchet wrench, and the like. Rotating the fasteners  250  into the endshield threaded holes  25  can compress the optional washer  260  sandwiching the washer  260  between the fastener head  252  and the internal ledge/lip  246 ,  248 , thus locking the fasteners  250  in place. 
     THIRD EMBODIMENT 
     FIG. 4A is a perspective exploded view of a third embodiment  300  of using either or both the captive fasteners  150 ,  250  of the preceding Figures, or a conventional fastener  50  with an alignment post  310  for attaching the mounting arm  40  to the a ceiling fan motor  10 . Referring to FIG. 4A, an alignment post  310  having tapered rounded sides with a narrow tip portion and an expanding bottom portion is located approximately half way between through-holes  45  in end  44  of blade mounting arm  40 . Opposite end  42 ′ of blade arm  40  has attachment points similar to those previously described. An opening  28  having a diameter the same as or slightly smaller than the diameter of the base portion of post  310  is located in the bottom of motor endshield  22 . 
     Similar to that previously described, bottom endshield  22  is attached to a rotating rotor  20  which is attached to a ceiling mounted motor  10 . Next as previously described, captive fasteners  250 ,  150  with or without rubber grommet washer  101  have their threaded ends moved in the direction of arrow G into through-holes  45  and are held captive therein. Next, the mounting arm  40  can be raised so that alignment post  310  is moved upward in the direction of arrow H into opening  28 , where the tapered sides of post  310  cause a snug fit when pushed upward as far as possible into opening  28 . Next fasteners  250 ,  150  are rotated and tightened into receiving threaded openings  25  in endshield  22 . Alternatively, a conventional fastener  50  such as but not limited to a regular head screw, Philips head screw and bolt can be used with or without grommet washer  101 . 
     FIG. 4B shows an alternative version of an alignment post  330  having flat side portions such as but not limited to a square, rectangle, hexagon, triangle and the like, along with a similarly configured opening  338  for the endshield  22  all for use with FIG.  4 A. Utilizing a non round alignment post  330  further forces the mounting arm  40  to be properly aligned in position beneath endshield  22 . Additionally non round alignment post can be tapered as well. 
     FIG. 4C is a perspective view of the third embodiment  300  of FIG. 4A using two alignment posts  340  which allows for only one captive  150 ,  250  or one conventional fastener  50  to hold the mounting arm  40  to the motor  10 . Referring to FIG. 4C, dual alignment posts  340  having similar shapes to those previously described above can be located opposite one another on end  44  of blade mounting arm  40 . Approximately halfway between can be a single through-hole  45 ′. Opposite end  42 ′ of blade arm  40  has attachment points similar to those previously described. Dual openings  29  having a diameter the same as or slightly smaller than the diameter of the base portion of posts  340  are located in the bottom of motor endshield  22  on both sides of threaded receiving holes  25 ′. 
     Similar to that previously described, bottom endshield  22  of rotating rotor  20  are attached to a ceiling mounted motor  10 . Next as previously described, a single captive fastener ( 250 ,  150  with or without rubber grommet washer  101 ) has its&#39; threaded end moved in the direction of arrow I into through-hole  45 ′ and is held captive therein. Next, the mounting arm  40  can be raised so that dual alignment posts  340  are moved upward in the direction of arrow J into openings  29 , where the tapered sides of posts  340  cause a snug fit when pushed upward as far as possible into openings  29 . Next the captive fastener  250 ,  150  is rotated and tightened into receiving threaded opening  25 ′ in endshield  22 . Alternatively, a single conventional fastener  50  such as but not limited to a regular head screw, Philips head screw and bolt can be used with or without grommet washer  101 . 
     The alignment posts can also allow the mounting arm to be evenly attached to the motor endshield and effectively eliminate wobbling effects when the ceiling fan is running. 
     While FIGS. 4A-4C show only one and two alignment posts, the invention can be practiced with three or more alignment posts as well. 
     Although the preferred embodiment describes the alignment post extending upward from the mounting arm with a mateable opening on the rotating member portion of the fan motor, the invention can be practiced with the alignment post(s) extending downward from the rotating member of the motor with the mateable opening on the mounting arm. 
     While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended.