Abstract:
An interchangeable fan blade system for a ceiling fan, made up of a set of fan support arms, and a complimentary set of interchangeable fan blades. The interchangeable fan blade system is a set of support arms attached to the rotating portion of the fan and having one of a variety of connectors for removably attaching one end of the fan blades to the support arm.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 09/727,706, filed Dec. 4, 2000, which is a divisional of U.S. patent application Ser. No. 09/363,832, filed Oct. 22, 1997, and now U.S. Pat. No. 5,944,486, issued Aug. 31, 1999, which claims the benefit of U.S. Provisional Patent Application Serial No. 60/042,381, filed Apr. 24, 1997. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates to ceiling fans, and more particularly to interchangeable decorative ceiling fan blades and an adapter for easy attachment and replacement of the blades on a ceiling fan.  
           [0004]    2. Description of Related Art  
           [0005]    Given the high energy cost of air conditioning, individuals have increasingly sought to reduce such costs by installing ceiling fans to provide air circulation at a much more modest cost than air conditioning. However, ceiling fans are often unsightly eyesores, and are difficult and dangerous to clean. Furthermore, in strong winds such as a hurricane, ceiling fan blades act as sails which can damage the fan and possibly injure people and destroy property.  
           [0006]    Typically, fan blades are bland in character in an attempt by the manufacturer to match every possible decor. Nevertheless, individuals have attempted to install decorative ceiling fans and blades to liven their surroundings. Replacement fan blades are available, but selection is extremely limited. Should an individual desire to replace fan blades, the holes of the replacement blades must match the hole arrangement of the support arms of the fan. Therefore, many types of blades are needed just to provide replacements for the different fans. While custom manufacture of blades is an option, it is prohibitively expensive for most users.  
           [0007]    Decorative ceiling fans and decorative component parts are well known in the prior art. One such ceiling fan is shown in U.S. Pat. No. Des. 256,614 which issued to Hoyt on Aug. 26, 1980, and discloses a combined ceiling fan cover plate and blade connectors which have a leaf-like appearance.  
           [0008]    Another similar invention is disclosed in U.S. Pat. No. Des 361,124 which issued to Pearce on Aug. 8, 1995. The invention disclosed is a ceiling fan with blades in the shape of an airplane propeller, with a decorative decal of a fighter plane which attaches to a ceiling, giving the appearance of an airplane dive-bombing in the room. Additionally, U.S. Pat. No. Des. 336,513 which issued to Junkin et al. on Jun. 15, 1993 discloses a ceiling fan blade that comprises fabric suspended by a tubular frame.  
           [0009]    U.S. Pat. No. 5,458,464 which issued to Lee on Oct. 17, 1995, discloses a blade mounting device for a ceiling fan. The device comprises a plurality of brackets, with a plurality of decorative inserts which have various configurations, profiles and colors. Only the inserts themselves are interchangeable, and the fan blades still require a significant amount of labor to remove.  
           [0010]    U.S. Pat. No. 5,470,205 which issued to Conklin, Jr. on Nov. 28, 1995, discloses a decorative ceiling fan blade removably mounted on a ceiling fan. A decorative sheet may be applied to an adhesive layer on the underside of the blade. Additionally, the blade has a plurality of openings positioned in three groupings, in order to accommodate a variety of threaded openings on a fan support arm.  
           [0011]    U.S. Pat. No. 5,486,094 which issued to Davis, Jr. et al. on Jan. 23, 1996, discloses a ceiling fan blade mounting bracket and support arms providing two fan blade support points, for reinforcing mounting of fan blades to the motor. These brackets do not provide for the easy removal of fan blades.  
           [0012]    U.S. Pat. No. 6,309,183 which issued to Bucher et al. on Oct. 30, 2001, describes a replaceable blade system for overhead ceiling fans which provides a mounting arm having flat topped fasteners and a replaceable blade having similarly disposed keyhole slots.  
           [0013]    None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus, an interchangeable fan blade system is desired to overcome the aforementioned shortcomings of the prior art.  
         SUMMARY OF THE INVENTION  
         [0014]    The present invention provides an interchangeable fan blade system for a ceiling fan. A set of adapters have a plurality of elongated attachment apertures that allow the adapter to be fitted onto virtually any type of fan support arm with the use of a set of shoulder screws. The adapter may be formed into any of a variety of configurations. The system further includes a complimentary set of interchangeable fan blades having a set of keyhole bores, with each blade being configured to accept the shoulder screws of the adapter. Each blade may be removably secured to a respective adapter by a variety of fasteners, including but not limited to hooks, locator pin and hold downs, snap buckles, hook arms, spring clips, quick release pins, snap-ins, and hook-and-loop fasteners.  
           [0015]    A second embodiment of the interchangeable fan blade system includes a set of interchangeable fan blades having a plurality of elongated attachment apertures which allow the blades to be secured to virtually any type of fan arm, by threading a plurality of shoulder cap screws and a plurality of male-female connectors though the plurality of elongated attachment apertures. The fan blade may be secured to the fan arm by either a knurled-knob screw with an elongated threaded portion, or a spring-clamp screw.  
           [0016]    A third embodiment of the interchangeable fan blade system includes a set of support arms that have shoulder screws adapted to removably attach to a set of keyhole bores of a complimentary set of interchangeable fan blades. Each blade may be removably secured to a respective support arm by a variety of fasteners, including but not limited to hooks, locator pin and hold downs, snap buckles, hook arms, spring clips, quick release pins, snap-ins, and hook-and-loop fasteners.  
           [0017]    Accordingly, it is a principal object of the invention to provide an interchangeable fan blade system that allows for easy replacement of fan blades with other fan blades of differing styles.  
           [0018]    It is another object of the invention to provide an interchangeable fan blade system whereby fan blades may be easily removed for cleaning and maintenance.  
           [0019]    It is a further object of the invention to provide an interchangeable fan blade system whereby fan blades may be easily removed in the event of inclement weather.  
           [0020]    It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.  
           [0021]    These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    [0022]FIG. 1 is a plan view of a first embodiment of the interchangeable fan blade system of the present invention shown in use on a conventional ceiling fan.  
         [0023]    [0023]FIG. 2 is a plan view of the adapter of the first embodiment shown attached to a fan support arm.  
         [0024]    [0024]FIG. 3 is a sectional view along lines  3 - 3  of FIG. 2.  
         [0025]    [0025]FIG. 4 is a plan view of an alternative adapter.  
         [0026]    [0026]FIG. 5A is a perspective view of an adapter having a first attachment, fan blade to the adapter.  
         [0027]    [0027]FIG. 5B is a perspective view of an adapter having second alternative attachment, fan blade to the adapter.  
         [0028]    [0028]FIG. 5C is a perspective view of an adapter having third alternative attachment, fan blade to the adapter.  
         [0029]    [0029]FIG. 5D is a perspective view of an adapter having fourth alternative attachment, fan blade to the adapter.  
         [0030]    [0030]FIG. 5E is a perspective view of an adapter having fifth alternative attachment, fan blade to the adapter.  
         [0031]    [0031]FIG. 5F is a perspective view of an adapter having sixth alternative attachment, fan blade to the adapter.  
         [0032]    [0032]FIG. 5G is a perspective view of an adapter having seventh alternative attachment, fan blade to the adapter.  
         [0033]    [0033]FIG. 6 is a perspective view of a second embodiment of the interchangeable fan blade system.  
         [0034]    [0034]FIG. 7A is a partial plan view of a fan blade having a first arrangement of attachment apertures.  
         [0035]    [0035]FIG. 7B is a partial plan view of a fan blade having a second arrangement of attachment apertures.  
         [0036]    [0036]FIG. 7C is a partial plan view of a fan blade having a third arrangement of attachment apertures.  
         [0037]    [0037]FIG. 8A is an enlarged scale, partial cross-sectional view of fan blade and fan support arm showing a fastener, fan blade to the fan support arm.  
         [0038]    [0038]FIG. 8B is an enlarged scale, partial cross-sectional view of fan blade and fan support arm showing another fastener for attaching the fan blade to the fan support arm.  
         [0039]    [0039]FIG. 9A is a perspective view of a third embodiment of the interchangeable fan blade system.  
         [0040]    [0040]FIG. 9B is a detail perspective view of another embodiment of the interchangeable fan blade system of FIG. 9A.  
         [0041]    [0041]FIG. 9C is a detail perspective view of another embodiment of the interchangeable fan blade system of FIG. 9A.  
         [0042]    [0042]FIG. 9D is a detail perspective view of the embodiment of FIG. 9C with the release member removed.  
         [0043]    [0043]FIG. 9E is a detail perspective view of the embodiment of the interchangeable fan blade system of FIG. 9A with the blade shown inverted.  
         [0044]    [0044]FIG. 9F is a detail perspective view of another embodiment of the interchangeable fan blade system of FIG. 9A.  
         [0045]    [0045]FIG. 9G is a detail perspective view as mounted of another embodiment of the interchangeable fan blade system of FIG. 9A.  
         [0046]    [0046]FIG. 9H is a detail perspective view of another embodiment of the interchangeable fan blade system of FIG. 9G.  
         [0047]    Similar reference characters denote corresponding features consistently throughout the attached drawings. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0048]    Referring now to the drawings wherein like numerals represent like elements, FIG. 1 is a plan view of the interchangeable fan blade system  10  in use on a conventional ceiling fan  12 , in accordance with a first embodiment of the invention. The system  10  includes a fan blade  14  and an adapter  16 . The adapter  16  enables variety of different fan blades  14  to fit virtually any type of ceiling fan  12 . Fan blades typically attach to the ceiling fan  12  by mounting the blades upon support arms  18  which are rotated by the fan motor (not shown). A conventional support arm  18  has a forked end that receives a fan blade by way of plurality of internally threaded cavities  24 , each of which is adapted to receive one of a plurality of threaded screws  20 . In ceiling fans  12  of the prior art, threaded screws  20  would pass through fan blade holes that align in registry with the threaded cavities  24  of the support arm  18 . The screws  20  would then be fitted into the threaded cavities of the support arm  18 , thereby securing the fan blade to the support arm.  
         [0049]    Referring now to FIGS. 2 and 3, the adapter  16  of the present invention has an arrangement of elongated attachment apertures  22  that align with the threaded cavities  24  of the support arm  18 . The screws  20  are threadably fitted to the threaded cavities of the support arm  18 , thereby allowing the adapter to be secured to a fan support arm  18  of virtually any size. FIG. 4 shows an alternative configuration for the adapter  16  of the present invention.  
         [0050]    With the adapter  16  installed upon the support arm, various fan blades  14  may be removably secured to the adapter  16 . This allows a user to easily remove and replace fan blades  14  when changing or cleaning the fan blades. FIGS. 2 and 3 illustrate one method of securing the blade  14  to the adapter  16 . A plurality of keyhole bores  26  are present on the proximal end of the blade  14 , and a complimentary plurality of shoulder screws  28  are affixed to the upper surface of the adapter. To removably secure the fan blade  14  to the adapter  16 , the keyhole bores  26  are first aligned in registry with and inserted over the shoulder screws  28 . The fan blade  14  is then pulled outwardly away from the adapter  16 , thereby securing the blade in place. Centrifugal force of the rotating fan  12  maintains the blade  14  in this secured position. The adapter  16  of FIG. 4 also employs shoulder screws  28  as fasteners.  
         [0051]    [0051]FIG. 5A shows alternative structure for attaching the fan blade  14  to the adapter  16 . A plurality of securing apertures  32  are present on the proximal end of the blade  14 , and a complimentary plurality of right-angled hooks  30  are affixed to the upper surface of the adapter. To removably secure the fan blade  14  to the adapter  16 , the securing apertures  32  are first aligned in registry with and inserted over the right-angle hooks  30 . The fan blade  14  is then pulled outwardly away from the adapter  16 , thereby securing the blade in place. Centrifugal force of the rotating fan  12  maintains the blade  14  in this secured position.  
         [0052]    [0052]FIG. 5B represents a second structure for attaching the fan blade  14  to the adapter  16 . A locator aperture  34  is present on the proximal end of the blade  14 , and a complimentary locator pin  36  and a hold-down  38  are integral with or otherwise connected to the upper surface of the adapter. Additionally, the proximal end of the blade  14  is planar, which allows the proximal end to fit under and against the hold-down  38 . To removably secure the fan blade  14  to the adapter  16 , the proximal end of the blade is inserted under and against the hold down  38 , and the locator aperture  34  is aligned in registry with and inserted over the locator pin  38 , thereby securing the blade in place.  
         [0053]    [0053]FIG. 5C represents a third structure for attaching the fan blade  14  to the adapter  16 . A locking tab  40  is present on the proximal end of the blade  14 , and a buckle  42 , similar to a safety-belt buckle, is affixed to the upper surface of the adapter  16 . To removably secure the fan blade  14  to the adapter  16 , the tab  40  is inserted into the buckle. To remove the blade  14  from the buckle  42 , a release member  44  is lifted, releasing the tab  40  from the buckle.  
         [0054]    [0054]FIG. 5D represents a fourth structure for attaching the fan blade  14  to the adapter  16 . A hook arm  50  is present on the proximal end of the blade  14 , and a retaining bar  52  suspended by a mounting bracket  38  is affixed to the upper surface of the adapter  16 . To removably secure the fan blade  14  to the adapter  16 , the hook arm  50  is inserted around the retaining bar  52 , thereby securing the blade in place. The mounting bracket  54  prevents lateral displacement of the blade  14 , and centrifugal force of the rotating fan  12  prevents axial displacement of the blade  14 .  
         [0055]    [0055]FIG. 5E represents a fifth structure for attaching the fan blade  14  to the adapter  16 . A pair of spring clips  56  are present on the proximal end of the blade, and a pair of shoulder screws  28  are affixed to the upper surface of the adapter  16 . To removably secure the fan blade  14  to the adapter  16 , the spring clips  56  are pressed together and inserted intermediate the pair of shoulder screws  28 . Upon insertion, the spring clips  56  are released to expand outward against the shoulder screws  28 , thereby securing the blade  14  in place.  
         [0056]    [0056]FIG. 5F represents a sixth structure for attaching the fan blade  14  to the adapter  16 . A pin-receiving cylinder  58  is present on the proximal end of the blade, and a pair of securing tabs  60 , each having a pin-receiving aperture  62  is affixed to the upper surface of the adapter  16 . To removably secure the fan blade  14  to the adapter  16 , the cylinder  58  is aligned in registry with the securing tabs  60  and a spring-loaded locking pin  64  is inserted through the pin-receiving apertures  62  and the cylinder, thereby securing the blade  14  in place.  
         [0057]    [0057]FIG. 5G represents a seventh structure for attaching the fan blade  14  to the adapter  16 . A pair of locking extensions  66  is present on the proximal end of the blade and complimentary pairs of locking tabs  68 , each having a mating recess  70 , are affixed to the upper surface of the adapter  16 . The recesses  70  are configured to receive the locking extensions  66  with a snap-fit, which allows the locking extensions to be repeatedly removed from and inserted into the recesses. To removably secure the fan blade  14  to the adapter  16 , the locking extensions  66  are inserted into the mating recesses  70  of a pair of locking tabs  68 , thereby securing the blade  14  in place.  
         [0058]    [0058]FIG. 6 represents a second embodiment of the interchangeable fan blade system  110 . The system  110  comprises a fan blade  114  having a series of elongated attachment apertures  122  that align with the threaded cavities  24  of the support arm  18 . The elongated attachment apertures  122  enable the blade  114  to fit virtually any fan support arm  18 . To removably install the second embodiment of the interchangeable fan blade system  110 , a knurled-knob screw  72  is inserted through the attachment aperture  122 , and a male-female connector  74  is then threaded onto the knurled-knob screw. The male-female connector  74  with the knurled-knob screw  28  threaded therein is then threadably fitted into the threaded cavities of the support arm  18 . FIGS. 7A, 7B and  7 C illustrate alternative configurations of fan blade attachment apertures  122 .  
         [0059]    [0059]FIG. 8A shows an alternative structure for removably attaching the fan blade  114  to the support arm  18 . A knurled-knob screw  72  with an elongated threaded portion  76  is threadably fitted to the threaded cavities of the support arm  18 , thereby eliminating the need for a male-female connector  74 . The knurled-knob screw  72  secures the fan blade  114  in place.  
         [0060]    [0060]FIG. 8B discloses a second structure for removably attaching the fan blade  114  to the support arm  18 . An overcenter, spring-clamp screw  78  is threadably fitted to the threaded cavities of the support arm  18 . The fan blade  114  is then secured in place by folding the spring clamp down over the blade  114 .  
         [0061]    [0061]FIG. 9 represents a third embodiment of the interchangeable fan blade system  210 . The system  210  includes a fan blade  14  and a support arm  211  adapted to receive the fan blade. A plurality of keyhole bores  26  are present on the proximal end of the blade  14 . The support arm  211  has a proximal end portion  214  having a plurality of threaded bores  15  for threaded attachment to the rotary portion  13  of a fan  12 . The support arm  216  has a distal end portion  212  having a plurality of shoulder screws  218  affixed to the upper surface thereof and complementary to keyhole bores  26  of blade  14 .  
         [0062]    To removably secure the fan blade  14  to the support arm  216 , the keyhole bores  26  are first aligned in registry with and inserted over the shoulder screws  218 . The fan blade  14  is then pulled distally away from the support arm  216 , thereby securing the blade in place. Centrifugal force of the rotating fan  12  maintains the blade  14  in this secured position. The structure for securing the fan blade  14  to the support arm shown in FIG. 9 is similar to that for securing the fan blade  14  to the adapter  16  shown in FIGS.  2 - 3 . The fasteners for securing the fan blade  14  to the support arm  216  may be chosen from a variety including hooks, locator pin and hold downs, snap buckles, hook arms, spring clips, quick release pins and snap-ins.  
         [0063]    Referring to FIG. 9B, there is shown alternative structure for attaching the fan blade  14  to the distal end  212  of arm  216 . A plurality of securing apertures  232  are present on the proximal end of the blade  14 , and a complimentary plurality of right-angled hooks  230  are affixed to the upper surface of the distal end  212  of arm  216 . To removably secure the fan blade  14  to the arm  216 , the securing apertures  232  are first aligned in registry with and inserted over the right-angle hooks  230 . The fan blade  14  is then pulled outwardly away from the arm  216 , thereby securing the blade in place. Centrifugal force of the rotating fan  12  maintains the blade  14  in this secured position.  
         [0064]    Referring to FIG. 9C and 9D there is shown another structure for attaching the fan blade  14  to the distal end  212  of arm  216 . A locking tab  240  having a rectangular groove cutout  242  is present on the proximal end of the blade  14 , and a buckle  246 , having a spring groove receiver  248  on its inner side and having a release member  244  similar to a safety-belt buckle mounted on the distal end  212  of arm  216 . To removably secure the fan blade  14  to the distal end  212 , the tab  240  is inserted into the buckle  246  depressing and locking over spring groove receiver  248 . To remove the blade  14  from the buckle  246 , the release member  244  is lifted, releasing the tab  240  from the buckle.  
         [0065]    Referring to FIG. 9E, there is shown another structure for attaching the fan blade  14  to the distal end  212  of arm  216 . A pair of locking extensions  254  is present on the proximal end of the blade and complimentary pairs of locking tabs  68 , each having a mating recess  250 , are affixed to the upper surface of the distal end  212  of arm  216 . The recesses  250  are configured to receive the locking extensions  254  with a snap-fit, which allows the locking extensions to be repeatedly removed from and inserted into the recesses. To removably secure the fan blade  14  to the distal end  212 , the locking extensions  254  are inserted into the mating recesses  250  of a pair of locking tabs  68 , thereby securing the blade  14  in place.  
         [0066]    Referring to FIG. 9F, there is shown another structure for attaching the fan blade  14  to the distal end  212  of arm  216 . A opposing grooves or notches  262  are located on opposing edges near the proximal end of blade  14  and forming notch ends  264  therein. A pair of complimentary hooded slot receivers  256  having hoods  258  are affixed to the upper surface of the distal end  212  of arm  216 . The slot receivers are the length of the corresponding notches  62  and have inward right angle retaining walls  260 . To removably secure the fan blade  14  to the arm  216 , the securing notches  262  are first aligned in registry with and inserted over the hooded slot receivers  256 . The fan blade  14  is then pulled outwardly away from the arm  216 , thereby pulling notch ends  264  under hoods  258  and against retaining walls  260  securing the blade in place. Centrifugal force of the rotating fan  12  maintains the blade  14  in this secured position.  
         [0067]    Referring to FIG. 9G, there is shown alternative structure for attaching the fan blade  14  to the distal end  212  of arm  216 . A plurality of peripherally located grooves or notches  266  are present on the proximal end of the blade  14 , and a complimentary plurality of inward-biased, upright spring snaps  264  are affixed to the upper surface of the distal end  212  of arm  216 . Spring snaps  264  have upper inward extending ends which extend of the fan blade  14  such that said fan blade is positively retained by said spring snaps when engaged therewith. To removably secure the fan blade  14  to the arm  216 , the grooves or notches  266  are first aligned in registry with the inward-biased, upright spring snaps  264 . The fan blade proximal end is then pushed downward, forcing the spring snaps  264  outward until the fan blade is seated and the upright spring snaps  264  snap shut over the upper surface of the fan blade, thereby securing the blade in place. The f an blade  14  may be removed by pushing outward on the snaps and pulling the blade from its seated position free of the snaps.  
         [0068]    Referring to FIG. 9H, there is shown another structure for attaching the fan blade  14  to the distal end  212  of arm  216 . A plurality of securing through bores  272  are present on the proximal end of the blade  14 , and a complimentary plurality of outward biased vertical two-piece snaps  270  are affixed to the upper surface of the distal end  212  of arm  216 . To removably secure the fan blade  14  to the arm  216 , the through-bores  272  are first aligned in registry with the snaps  270 . The fan blade is then forced downward forcing the snaps  270  inward until the fan blade  14  is seated and the snaps snap outward, thereby securing the blade in place. The fan blade  14  may be removed by pinching the upper part of the snaps together and lifting the blade from its seated position free of the snaps.  
         [0069]    Additionally, the fasteners for removably attaching a fan blade to a respective adapter or support arm may include hook-and-loop fasteners, snap buttons, cotter pins, drive pins, magnets, dovetails, screws, clevis pins, keyways, cogs, bolts, retaining rings, straps, buckles, tape, chains, zippers, wires, twist locks, twist ties, chucks, clamps, pinchers, cranks, vacuum seals, S-hooks, slip hooks, studs and shanks.  
         [0070]    It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.