Abstract:
A removable grommet for attaching a string to an object, the grommet includes a barrel defining a central channel extending through a first section and a second section of the barrel, the first section being sized to allow the string, but not a knotted portion of the string, to pass through, and the second section being sized to allow the knotted portion of the string to pass through.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority of U.S. Provisional Patent Application No. 61/009,819, filed Jan. 2, 2008, the disclosure of which is hereby incorporated by reference. 
     
    
     PRELUDE 
       [0002]    This disclosure is generally related to devices and methods of attaching string to objects and, more specifically, to devices and methods for stringing athletic racquets to ensure the tension of the racquet is not substantially compromised other than through material failures of the string itself. 
         [0003]    It is a first aspect of the present invention to provide a removable grommet for attaching a string to an object, the grommet includes a barrel defining a central channel extending through a first section and a second section of the barrel, the first section being sized to allow the string, but not a knotted portion of the string, to pass through, the second section being sized to allow the knotted portion of the string to pass through. In a more detailed embodiment of the first aspect, the central channel is at least partially defined by an internal shoulder extending from an interior surface of the barrel, and the internal shoulder is operative to distinguish the first section from the second section. In yet another more detailed embodiment, the grommet includes a flange extending radially from the barrel. In a further detailed embodiment, the flange is circumferential and extends generally perpendicularly from the barrel. In still a further detailed embodiment, the central channel of the first section is substantially cylindrical and includes a first diameter, and the central channel of the second section is substantially cylindrical and includes a second diameter, where the first diameter is greater than twice the second diameter. In a more detailed embodiment, a first interior wall of the barrel within the first section is substantially cylindrical and defines a first cavity, and a second interior wall of the barrel within the second section is substantially cylindrical and defines a second cavity, where the first interior wall is joined to the second interior wall by a horizontal wall. In a more detailed embodiment, the barrel is a frustrum. In another more detailed embodiment, an exterior longitudinal surface of the barrel is cylindrical. 
         [0004]    It is a second aspect of the present invention to provide a grommet for attaching a string to an object, the grommet including a central bore extending through a barrel, the central bore including a first chamber at least partially defined by a first vertical interior wall of the barrel, a second chamber at least partially defined by a second vertical interior wall of the barrel, where the barrel includes a horizontal interior wall bridging the first vertical interior wall and the second vertical interior wall. 
         [0005]    In a more detailed embodiment of the second aspect, the first chamber is substantially cylindrical, the second chamber is substantially cylindrical, and the first chamber is more than twice the diameter of the second chamber. In yet another more detailed embodiment, the grommet includes a flange extending radially from a distal end of the barrel. In a further detailed embodiment, the flange is circumferential and extends generally perpendicularly from the barrel. In still a further detailed embodiment, the barrel is a frustrum. In a more detailed embodiment, an exterior longitudinal surface of the barrel is cylindrical. 
         [0006]    It is a third aspect of the present invention to provide a method of securing a string to an object comprising the acts of: (a) providing a grommet including a barrel with a longitudinal bore having a diameter that varies along at least a portion of the longitudinal bore, where an interior of the barrel includes at least one radially extending internal wall; (b) mounting the grommet to the object; (c) passing at least a portion of the string through the longitudinal bore of the grommet; (d) tying a length of the string in a knot; and, (e) applying tension to the string to draw the knot into the longitudinal bore to abut the at least one radially extending internal wall, where the radially extending internal wall inhibits passage of the knot through the entire longitudinal bore. 
         [0007]    In a more detailed embodiment of the third aspect, at least one radially extending internal wall cooperates with a first vertical internal wall of the barrel to at least partially define a substantially cylindrical cavity which the knot is recessed within. In yet another more detailed embodiment, the grommet includes a circumferential flange extending from a distal end of the barrel. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a cross-sectional view of a first exemplary grommet in accordance with the present disclosure; 
           [0009]      FIG. 2  is a cross-sectional view of a second exemplary grommet in accordance with the present disclosure; 
           [0010]      FIG. 3  is a cross-sectional view of the first exemplary grommet of  FIG. 1  installed in a tennis racquet section; 
           [0011]      FIG. 4  is a cross-sectional view of the first exemplary grommet of  FIG. 1  installed in a tennis racquet section along with string; 
           [0012]      FIG. 5  is a cross-sectional view of the second exemplary grommet of  FIG. 2  installed in a tennis racquet section; and 
           [0013]      FIG. 6  is a cross-sectional view of the second exemplary grommet of  FIG. 2  installed in a tennis racquet section along with string. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    The exemplary embodiments relate to devices and methods of attaching string to objects and, more specifically, to devices and methods for stringing athletic racquets to ensure the tension of the racquet is not substantially compromised other than through material failures of the string itself. Of course, it will be apparent to those of ordinary skill in the art that the preferred embodiments discussed below are exemplary in nature and may be reconfigured without departing from the scope and spirit of the present invention. However, for clarity and precision, the exemplary embodiments as discussed below may include optional steps, methods, and features that one of ordinary skill should recognize as not being a requisite to fall within the scope of the present invention. 
         [0015]    Referring to  FIGS. 1 ,  3 , and  4 , a first exemplary grommet  10  includes a knot end  12  and a string end  14 . The knot end  12  is adapted to receive a knot  16  (See  FIG. 4 ) tied in a string  18  which extends through the grommet  10 . The first exemplary grommet  10  includes a barrel  20  having a circular central channel or bore  22  extending from the string end  14  to the knot end  12 . A pair of vertical walls  24 ,  26  cooperate with a horizontal wall  28  to define distinct cylindrical cavities  30 ,  32  within the barrel  20 . In exemplary form, the horizontal wall  28  can be considered to form an internal shoulder. 
         [0016]    The exterior of the barrel  20  has a substantially conical shape that tapers from the knot end  12  to the string end  14 . Proximate the knot end  12 , a circumferential flange  34  extends from the barrel  20  to increase the cross-section of the grommet. As will be discussed hereafter, this increased cross-section inhibits a string knot  16  from passing through the entire length of the channel  22 . 
         [0017]    The channel  22  may have a generally circular cross section and may vary in diameter over its length. In particular, the channel  22  at the knot end  12  of the grommet  10  has a diameter more than three times that of the channel diameter at the string end  14 . As discussed hereafter, the difference in diameters along the length of the channel  22  is operative to allow the string to pass through the channel while preventing the knot  16  in the string  18  from passing through. 
         [0018]    It is within the scope of the disclosure to utilize various transitions along the length of the channel  22  between the string end  14  to the knot end  12 . For example, the transition may comprise a step change or may comprise a projection extending radially into the channel. It is also within the scope of the disclosure to utilize a grommet  10  having a central channel  22  with a cross section other than circular. For example and without limitation, the central channel or portions of the central channel may have oval, rectangular, square, triangular, or other cross sections. 
         [0019]    Referring specifically to  FIGS. 3 and 4 , installation and utilization of the first exemplary grommet  10  includes inserting the string end  14  into an opening  36  within the perimeter of a sporting racquet  38 . The flange  34  of the grommet  10  is oriented to abut the outermost surface of the racquet  38  so that tension upon the string  18  is operative to push/pull the flange  34  snuggly against the outermost surface of the racquet  38 . In this way, the grommet  10  is ultimately mounted to the racquet  38  using the tension of the string  18 . Thereafter, the string  18  is threaded through the channel  22  so that at least a continuous portion of the string extends completely through the channel. 
         [0020]    In use, it is anticipated that the string will be in tension and maintained in tension by a racquet stringing machine (not shown) or other similar device. While the string  18  is in tension, a knot  16  is formed in the string proximate the knot end  12  of the grommet  10 . Thereafter, the string  18  is released from the racquet stringing machine, but still maintained in tension, so that the knot  16  becomes seated within the larger cavity  30  of the grommet  10 . Because the diameter of the smaller cavity  32  is too small to allow throughput of the knot  16 , the knot remains seated against the horizontal wall  28 , but recessed within the grommet  10 . It is to be understood that the openings  36  formed though the racquet  38  are commonly the same size. But in certain instances the openings may have varied diameters between inside and outside and thus the first exemplary grommet is particularly useful where openings are not of substantially the same size/diameter. 
         [0021]    Referring to  FIGS. 2 ,  5 , and  6 , a second exemplary grommet  110  includes a knot end  112  and a string end  114 . The knot end  112  is adapted to receive a knot  116  (See  FIG. 6 ) tied in a string  118  which extends through the grommet  110 . The second exemplary grommet  110  includes a barrel  120  having a circular central channel or bore  122  extending from the string end  114  to the knot end  112 . A pair of vertical walls  124 ,  126  cooperate with a horizontal wall  128  to define distinct cylindrical cavities  130 ,  132  within the barrel  120 . In exemplary form, the horizontal wall  128  can be considered to form an internal shoulder. 
         [0022]    The exterior of the barrel  120  has a substantially cylindrical shape with a substantially constant external diameter from the knot end  112  to the string end  114 . Proximate the knot end  112 , a circumferential flange  134  extends from the barrel  120  to increase the cross-section of the grommet. As will be discussed hereafter, this increased cross-section inhibits a string knot  116  from passing through the entire length of the channel  122 . 
         [0023]    The channel  122  may have a generally circular cross section and may vary in diameter over its length. In particular, the channel  122  at the knot end  112  of the grommet  110  has a diameter more than three times that of the channel diameter at the string end  114 . As discussed hereafter, the difference in diameters along the length of the channel  122  is operative to allow the string to pass through the channel while preventing the knot  116  in the string  118  from passing through. 
         [0024]    It is within the scope of the disclosure to utilize various transitions along the length of the channel  122  between the string end  114  to the knot end  112 . For example, the transition may comprise a step change or may comprise a projection extending radially into the channel. It is also within the scope of the disclosure to utilize a grommet  110  having a central channel  122  with a cross section other than circular. For example and without limitation, the central channel  122  or portions of the central channel may have oval, rectangular, square, triangular, or other cross sections. 
         [0025]    Referring specifically to  FIGS. 5 and 6 , installation and utilization of the second exemplary grommet  110  includes inserting the string end  114  into an opening  136  within the perimeter of a sporting racquet  138 . The flange  134  of the grommet  110  is oriented to abut the outermost surface of the racquet  138  so that tension upon the string  118  is operative to push the flange  134  snuggly against the outermost surface of the racquet  138 . In this way, the grommet  110  is ultimately mounted to the racquet  138  using the tension of the string  118 . Thereafter, string  118  is threaded through the channel  122  so that at least a continuous portion of the string extends completely through the channel. 
         [0026]    In use, it is anticipated that the string will be in tension and maintained in tension by a racquet stringing machine (not shown) or other similar device. While the string  118  is in tension, a knot  116  is formed in the string proximate the knot end  112  of the grommet  110 . Thereafter, the string  118  is released from the racquet stringing machine, but still maintained in tension, so that the knot  116  becomes seated within the larger cavity  130  of the grommet  110 . Because the diameter of the smaller cavity  132  is too small to allow throughput of the knot  116 , the knot remains seated against the horizontal wall  128 , but recessed within the grommet  110 . It is to be understood that the openings  136  formed though the racquet  138  are commonly the same size. But in certain instances the openings may have varied diameters between inside and outside and thus the first exemplary grommet is particularly useful where openings are not of substantially the same size/diameter. 
         [0027]    Exemplary embodiments of the present disclosure may be constructed from materials such as plastics, aluminum (or other metals), composites (such as fiberglass, graphite, carbon fiber, etc.) or any combination thereof. In an exemplary embodiment, the grommet  10 ,  110  is constructed of Delrin thermoplastic. 
         [0028]    Although the exemplary grommets  10 ,  110  have been described herein with reference to stringing a tennis or other racket, the invention may be utilized in any context in which the invention may prove advantageous. In such other uses, the string described above may be any flexible line or cord, such as, but not limited to, rope, monofilament, cord, cable, etc. 
         [0029]    While exemplary embodiments of the invention have been set forth above for the purpose of disclosure, modifications of the disclosed embodiments of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, it is to be understood that the invention not limited to the above precise embodiments and that changes may be made without departing from the scope of the invention. Likewise, it is to be understood that it is not necessary to meet any or all of the stated advantages or objects of the invention disclosed herein to fall within the scope of the invention, since inherent and/or unforeseen advantages of the present invention may exist even though they may not have been explicitly discussed herein. All references mentioned herein are incorporated by reference.