Patent Publication Number: US-6708428-B2

Title: Quick-release connector system for footwear with reliable engagement

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a quick-release connector system for footwear with reliable engagement. In particular, the present invention relates to a shoe cleat that can be quickly attached to or detached from a cleat holder fixed in an underside of footwear while providing a reliable engagement between the shoe cleat and the cleat holder. 
     2. Description of the Related Art 
     Shoe cleats attached to an underside of footwear are useful in providing a reliable engagement with grass or soft soil, thereby preventing slip. For example, the shoe cleats allow a golfer to swing the golf club without the risk of slip in the feet. Metal spikes are hardly used now, as they damaged the grass and provided insufficient grounding effect. Further, the metal spikes caused an uncomfortable feeling while walking, as the reactive force from the ground was transmitted through a point back to the foot of the wearer. FIG. 2 of the drawings illustrates a conventional shoe cleat  12  made of rubber and FIG. 1 illustrates a shoe having a plurality of shoe cleats  12  attached to an underside of a sole  2  thereof. The shoe cleat  12  includes a plurality of spaced ground-engaging spikes  10 , providing the required grounding effect and friction. The reactive force from the ground is distributed in a uniform manner, providing a comfort wearing for the wearer. Referring to FIG. 2, the shoe cleat  12  includes a threaded spigot  13  for threading engagement with a holder  11  embedded in the underside of the sole  2 . 
     Different spikes provide different grounding effect and friction. Thus, the shoe cleats are sometimes changed in response to the terrain and weather. However, detachment/attachment of the shoe cleats is troublesome. Quick-release connector systems have been proposed in e.g., U.S. Pat. Nos. 5,768,809, 6,108,944, and 6,332,281, all to Savoie, U.S. Pat. Nos. 5,974,700 and 6,272,774, both to Kelly, and U.S. Pat. No. 5,123,184 to Ferreira. The shoe cleats can be easily, threadedly engaged with the cleat holders by turning the respective cleat through a small angle. However, it was found that the cleats were apt to be disengaged from the cleat holders, as the engaging force between the shoe cleats and the cleat holders are poor. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a shoe cleat that can be quickly attached to or detached from a cleat holder fixed in an underside of footwear while providing a reliable engagement between the shoe cleat and the cleat holder. 
     A quick-release connector system for footwear in accordance with the present invention comprises a cleat holder fixed in an underside of footwear and a shoe cleat. The cleat holder comprises a base and a hub projecting from a side of the base. The hub includes a plurality of lobes on an outer periphery thereof and a screw-threaded bore. Each two of the lobes adjacent to each other have an indentation therebetween. A plurality of grooves are defined in the side of the base, each groove having a portion extending to the indentation between two of the lobes that are adjacent to each other. 
     The shoe cleat comprises a cleat body, a screw-threaded spigot projecting from a side of the cleat body, and a spike unit formed on another side of the cleat body. The screw-threaded spigot is releasably engageable with the screw-threaded bore of the cleat holder through rotary insertion between a released position and an engaged position. A plurality of spaced protrusions are formed on the side of the cleat body and located around the screw-threaded spigot. Each protrusion of the shoe cleat is retained in place by an associated one of the grooves and an associated one of the indentations of the cleat holder when the screw-threaded spigot is in the engaged position. 
     Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a shoe having conventional shoe cleats attached thereto. 
     FIG. 2 is an enlarged side view, partly in section, of a shoe cleat and a cleat holder fixed in a sole of the shoe in FIG.  1 . 
     FIG. 3 is an enlarged sectional view of a shoe cleat and a cleat holder in accordance with the present invention. 
     FIG. 4 is a perspective view of the cleat holder in accordance with the present invention. 
     FIG. 5 is a perspective view of the shoe cleat in accordance with the present invention. 
     FIG. 6 is a sectional view similar to FIG. 3, wherein the shoe cleat is in a position ready for engaging with the cleat holder. 
     FIG. 7 is a sectional view similar to FIG. 6, wherein the shoe cleat is turned through an angle. 
     FIG. 8 is a plan view of the shoe cleat and cleat holder in FIG.  3 . 
     FIG. 9 is a perspective view of another embodiment of the cleat holder in accordance with the present invention. 
     FIG. 10 is a perspective view of another embodiment of the cleat holder in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 3, a quick-release connector system for footwear with reliable engagement in accordance with the present invention generally comprises a shoe cleat  4  and a cleat holder  3  that is fixed to an underside of footwear, e.g., a sole  2  of a sport shoe. 
     Referring to FIG. 4, the cleat holder  3  comprises a base  32  and a hub  31  projecting from a side of the base  32 . The hub  31  includes a plurality of lobes  33  on an outer periphery thereof and a screw-threaded bore  312 . In this embodiment, three spaced helical threads  311  are formed on an inner periphery defining the screw-threaded bore  312 . Further, a plurality of grooves  34  is defined in the side of the base  32 , each groove  34  having a portion extending to an indentation  36  between two lobes  33  that are adjacent to each other. 
     Referring to FIG. 5, the shoe cleat  4  includes a cleat body  42 , a screw-threaded spigot  41  projecting from a side of the cleat body  42 , and a spike unit  45  formed on the other side of the cleat body  42 . In this embodiment, three spaced helical threads  411  corresponding to the helical threads  311  of the cleat holder  31  are formed on an outer periphery of the screw-threaded spigot  41 . Thus, the screw-threaded spigot  41  of the cleat  4  is releasably engageable with the screw-threaded bore  312  of the cleat holder  3  through rotary insertion. Further, a plurality of spaced protrusions  43  are formed on the side of the cleat body  42  and located around the screw-threaded spigot  41 . The spike unit  45  includes a plurality of ground-engaging spikes  46  on an underside thereof. The spike unit  45  and the cleat  42  may be integrally formed with each other by injection molding. 
     In assembly, referring to FIG. 6, the screw-threaded spigot  41  of the shoe cleat  4  is aligned with and inserted into the screw-threaded bore  312  of the cleat holder  3 . Next, the shoe cleat  4  is turned through an angle such that the helical threads  411  of the screw-threaded spigot  41  are engaged with the helical threads  312  of the screw-threaded bore  312 , as shown in FIG.  7 . It is noted that each protrusion  43  of the shoe cleat  4  is engaged in an indentation  36  between two lobes  33  that are adjacent to each other. Further rotation of the shoe cleat  4  allows the protrusion  43  to move across the next lobe  33  into the next indentation  36 , and each protrusion  43  is engaged into an associated groove  34  of the cleat holder  3 , best shown in FIG.  8 . 
     Thus, each protrusion  43  on the shoe cleat  4  is retained in its engaged position by the associated indentation  36  between two lobes  33  and the associated groove  34  of the cleat holder  3 , as shown in FIG.  8 . The engagement between the shoe cleat  4  and the cleat holder  3  is reliable. Attachment of the shoe cleat  4  to the cleat holder  3  is easily achieved by manually turning the shoe cleat  4  through a relatively small angle. Detachment of the shoe cleat  4  from the cleat holder  3  can be achieved by means of extending two engaging legs (not shown) of a tool (not shown) into two engaging holes  47  (see FIGS. 3 and 8) and then turning the tool in a reverse direction to a released position, thereby disengaging the protrusions  43  from the grooves  34  and the indentations  36  of the cleat holder  3  for subsequent removal of the shoe cleat  4  from the cleat holder  3 . 
     The grooves  34  of the cleat holder  3  and the protrusions  43  of the shoe cleat  4  are triangular in the first embodiment shown in FIGS. 4 and 5. Nevertheless, the grooves  34  and the protrusions  43  may be of any other shapes. For example, the grooves  34  may be circular and the protrusions  43  may be cylindrical, as illustrated in FIGS. 9 and 10. The shoe cleat  4  in FIG. 10 also includes a cleat body  42 , a screw-threaded spigot  41  projecting from a side of the cleat body  42 , and a spike unit  5  formed on the other side of the cleat body  42 . The spike unit  5  includes a plurality of ground-engaging spikes  50  on an underside thereof Similar to the first embodiment, each protrusion  43  on the shoe cleat  4  is retained in place by the associated indentation  36  between two lobes  33  and the associated groove  34  of the cleat holder  3 . 
     Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the invention as hereinafter claimed.