Patent Publication Number: US-2010112894-A1

Title: Expanding and contracting yo-yo

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to toys, and more particularly to an expanding and contracting yo-yo having leaves or air foils on both sides that expand to unfold the leaves and contract to form a dome as the yo-yo string winds and unwinds. 
     2. Description of the Related Art 
     The yo-yo is a spool-like toy comprising two substantially rigid disks connected by a dowel pin in the center to which a string is attached. One end of the string is looped around the player&#39;s finger so that the toy can be spun out and reeled in by wrist motion. Part of the appeal of the yo-yo is simply the skill of the player in performing certain tricks with the yo-yo. Another part of the appeal is the decorative or ornamental appearance of the yo-yo resulting from the colors or designs of the flat side faces of the yo-yo as the string winds and unwinds, and as the spool spins at the end of the string when fully extended. 
     In order to maintain the popularity of the yo-yo and commercial demand for the yo-yo, however, there is a continuing need for developing new visual effects to attract attention to the yo-yo. Thus, an expanding and contracting yo-yo solving the aforementioned problems is desired. 
     SUMMARY OF THE INVENTION 
     The expanding and contracting yo-yo is a spool formed by a pair of disks connected by a narrow diameter pin having a string wound around the pin. At least one, and preferably both, of the disks has a plurality of overlapping wings (also referred to as air foils or leaves) pivotally attached to the periphery of the outer face of the disk. The wings are capable of expanding outward to unfold like the petals of a flower and contracting to form a dome on the outer face, similar to a closed flower bud. The yo-yo has a flexible, resilient loop attached to the inner face of the wings to bias the wings to the closed dome configuration. When the yo-yo is dropped and pulled back in, centrifugal force, centripetal force, alternate lift and drag of air flow, and resilient bias cause the wings to alternately pivot and unfold outward, followed by pivoting inward to reform the dome shape. 
     These and other features of the present invention will become readily apparent upon further review of the following specification and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an environmental, perspective view of an expanding and contracting yo-yo according to the present invention. 
         FIG. 2  is a top view of the expanding and contracting yo-yo according to the present invention. 
         FIG. 3  is a perspective view of a single disk of an expanding and contracting yo-yo according to the present invention, showing the wings contracted. 
         FIG. 4  is a perspective view of an expanding and contracting yo-yo according to the present invention, showing the wings expanded. 
         FIG. 5  is an alternative embodiment comprising a spinning top according to the present invention. 
     
    
    
     Similar reference characters denote corresponding features consistently throughout the attached drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As shown in  FIGS. 1-4 , the expanding and contracting yo-yo  10  has a plurality of overlapping wings  15  pivotally to the periphery of at least one disk  30 , and preferably both disks  30 , on each side of the yo-yo  10 . The wings  15 , also referred to as air foils or leaves, pivot outwardly to an open, expanded position as the string R unwinds, and pivot inwardly to a contracted, domed position as the string R rewinds or when the yo-yo assumes a stationary position. Moreover, adjacent wings  15  may be designed to have contrasting color schemes, textures, or the like. Preferably, the wings  15  define a dome having an open axial center region when the wing members  15  are in a closed configuration, although the wings  15  may pivot to a flat position substantially coplanar with the rim of the disk  30  or parallel to the rigid outer face or hub of the disk  30 . 
     In a most general form, yo-yo  10  is a spool having two disks or disk-like members  30  made from wood, plastic, metal, composite materials, or the like, which are connected by a dowel pin D at their axial center, and a string R attached to and wound around the dowel pin D. One end of the string has a loop L that the player&#39;s finger or other extremity can engage so that the toy can be spun out and reeled in by wrist, or other appropriate motion. Often yo-yos are manufactured so that the disks  30  extend laterally into domes to provide greater stability of motion, better aerodynamics, and enhanced aesthetic appeal to the design. 
     In addition to the general yo-yo design, yo-yo  10  includes a plurality of multiple overlapping wings  15  pivotally attached to the periphery of disks  30  on each side of yo-yo  10 . The wings  15  are resiliently biased to the contracted, dome position by a flexible, resilient member  52 , which is preferably formed into a loop and attached to each of the wings  15 . The flexible resilient member may be an elastic band, a rubber band, an elastic cord made from a material similar to pony tail loops or bungee cords, etc. Each resilient member may be looped through a plurality of tubular band retainers  50 , each band retainer  50  being disposed on a respective wing member  15  radially outward from a pivot point formed by the attachment of pivot pin  40  of winged member  15  to hinge tube  35  peripherally disposed on disk  30 . Wings  15  may be pivotally attached to the periphery of disk  30  in any desired manner, including by a living hinge, mechanical hinge, etc. The configuration of band retainers  50  on winged members  15  causes the winged members to be normally closed absent rotational movement of yo-yo  10 . When a user rotates the yo-yo  10 , the resilient bias provided by flexible, resilient member  52  is overcome by centrifugal force and lift from airflow to thereby open the hinged wings  15 . When the yo-yo  10  is rewound, centripetal force, air drag, and the resilience of resilient member  52  return the wings  15  to their resting position against disks  30 . 
     The embodiment, as described in  FIGS. 1-4 , exemplifies the invention in the form of a yo-yo  10 . However, other embodiments are contemplated and can be incorporated into other types and styles of devices. Exemplary of these other types of devices is the spinning top  10 ′, as shown in  FIG. 5 , having overlapping wings  15 , same as in the embodiment shown in  FIG. 2 . The dowel pin D has been replaced by a tapered body D′. The spinning top  10 ′ incorporates a pull string coming out of tapered body D′ in a conventional manner. When the top  10 ′ is thrown and the pull string is pulled and disengaged from the top  10 ′, the spinning motion of the top allows the overlapping wings  15  to expand as described in the aforementioned embodiment 10. Thus, it can be seen that many types of spinning devices can be fashioned while incorporating a plurality of spring biased overlapping wings which are centrifugally reactive to cause the wings to expand open when the device is spinning. These devices include, for example without limitation, flying or spinning discs, domes, tops, gyroscopic tops, and other types of rotating, spinning or whirling devices. 
     It is to be understood that the present invention is not limited to the embodiment described above, but encompasses any and all embodiments within the scope of the following claims.