Patent Publication Number: US-6902374-B2

Title: Ceiling fan

Description:
TECHNICAL FIELD 
     This invention relates to ceiling fans and more specifically to mechanisms by which their fan blades are mounted and dismounted. 
     BACKGROUND OF THE INVENTION 
     Electrically powered ceiling fans typically have a motor mounted within a stationary housing that is suspended from a ceiling. In operation, the motor rotates a blade iron that has an annulus from which individual extensions in the form of blade irons radiate. The several blades of the fan are mounted to these blade irons. 
     Ceiling fans are usually sold at retail with their blades packed separately from the fan housing for compactness. The housing is normally mounted in suspension from the ceiling through a downrod and then the blades are mounted to the blade irons. To do this, the blades have been mounted to the irons with screws or bolts. This has been cumbersome and tedious as the installer has had to be elevated on a ladder or platform and work above his head. This work has entailed aligning the mounting holes of the blade and blade iron and torquing the fasteners all while having to hold the blade above his head and often under poor lighting conditions . For blade replacement, the same task has been involved. 
     Accordingly, it is seen that a need has long existed for a ceiling fan capable of having its blades mounted and dismounted in a more efficient and easier manner. It is to the provision of such that the present invention is primarily directed. 
     SUMMARY OF THE INVENTION 
     In its preferred form, a ceiling fan comprises an annular array of blade irons adapted to be rotatably driven by a motor, said blade irons having opposite sides formed with at least one notch. The fan has fan blades with each blade bearing a bracket having opposite side walls, each formed with at least one indentation sized and positioned to be passed through a blade iron side notch. So constructed, the blades may be mounted to the blade irons by passing the blade bracket indentations through the blade iron notches and then sliding the brackets to a position with the bracket indentations unaligned with the blade iron notches thereby interlocking the blade brackets with the blade irons. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the top of a ceiling fan that embodies principles of the invention in its preferred form. 
         FIG. 2  is a perspective view of the bottom of the ceiling fan shown with several of its blades removed. 
         FIG. 3  is an exploded view of parts employed in mounting one of the fan blades. 
         FIG. 4  is a top view of a portion of the fan. 
         FIG. 5  is a side view of the portion of the fan shown in FIG.  4 . 
         FIG. 6A  is a top view of a clip component of the fan while  FIG. 6B  is a side view thereof. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now in more detail to the drawing, there is shown a ceiling fan  10  having a motor housing  11  suspended from an unshown ceiling by a downrod or rod  12 . An unshown electric motor is mounted with the housing  11  and connected to a source of electric power by wires that extend through the rod  12 . The motor rotatably drives an annular blade iron that has six radiating extensions or fins  14  that are slightly tilted so that blades mounted thereon have an angle of attack as they are rotated to create a downward or upward flow of air depending upon the other direction of rotation. Each of these extensions is also referred to herein as a blade iron. They are essentially mounting tabs but are referred to in the trade as irons. Each blade iron (extension) is seen to be of a generally trapezoidal shape so that their side edges  15  taper outwardly as they extend from the motor housing. Each is formed with two threaded mounting holes  16  and a slot  17 . Each side edge  15  is formed with two notches  18 . A resilient leaf spring clip  20  in drawing  FIG. 1  is mounted atop each blade iron by unshown screws passed through clip holes  21 . As best seen in  FIGS. 6A and 6B , the clip has a flat portion in which the holes  21  are formed and a raised, arcuate portion  22 . A racetrack shape slot  23  spans the portions  22  and  23 . 
     With continued reference to the drawing, the ceiling fan  10  is further seen in  FIG. 1  to have six fan blades  25  while  FIG. 2  shows the concept with  5  blade irons. Each blade is formed with a trapezoidal opening  26  near its inboard end as best shown in FIG.  3 . By inboard is meant that portion closer to the fan&#39;s axis of rotation. A bracket  28  is press-fitted into the blade opening  26 . The bracket has a flat floor  29  in which two mounting holes  30  and one pass-through hole  31  are formed. Divergent, opposed sides  32  of the bracket are formed with two arcuate indentations  33  adjacent to the upper edge of the bracket sides. A decorative medallion  35  is mounted flushly against the bottom of the fan blade  25  by two screws  36  passed through the two bracket mounting holes  30  and threaded into two medallion bosses  37 . A pin  40  extends from the medallion through the bracket pass-through hole  31 . The top of the pin  40  is beveled. 
     So constructed the fan blades  25  may be easily and quickly dismounted from the blade irons  14  in two steps. First, the blade is raised upwardly against the bottom of the blade iron to bring its bracket  28  into a position cradling the blade iron  14 . As this is done, pin  40  passes through blade iron slot  17  so as to project above the blade iron, and the four bracket indentations  33  pass through the four blade iron notches  18 . The blade with its bracket  28  is then moved outwardly away from the fan&#39;s axis. This action moves the bracket indentation  33  into a position aside the blade iron notches  18  with the bracket indentations pressed against the top surface of the blade iron thereby capturing and becoming locked to the blade iron. This also causes the divergent sides of the bracket to be wedged snugly against the divergent sides  15  of the blade iron. Simultaneously, the beveled top of the pin  40  is driven against the raised portion of the resilient clip causing it to flex upwardly until the pin enters the clip slot  23 . As this occurs, the raised portion of the clip springs back thereby capturing the pin within the slot  23 . In this manner, the bracket and blade become interlocked vertically, horizontally and laterally. Rotation of the blades can only allow minimal slope as the pin  40  engages an end of the racetrack shaped slot  17 . Rotations of the blades during fan use between the bracket and blade iron also enhances the security of the mounting as it increases the wedging force. 
     To dismount a blade, the raised end of the clip is simply raised and the blade moved radially inboard. This movement causes the pin  40  to become free of the clip  20  and the bracket positioned to fall free from the blade iron. 
     It thus is seen that a ceiling fan is now provided of a construction that enables their blades to be mounted and dismounted easily, quickly and in a reliable and secure manner. Although the invention has been illustrated and described in its preferred form, it should be understood that many modifications, deletions and additions may be made thereto without departure from its spirit and scope as set forth in the following claims.