Sports racket and method of manufacturing same

Abstract

A sports racket is provided that has a racket body with a racket head. The racket head has a frame that has substantially rectangular face shape with appropriately rounded corners. The frame has a string mounting positions in a predetermined arrangement on the four sides of the rectangular face shape. There are lockable grommets integrally disposed in the frame with each grommet at a different string mounting position. A string mounted to the racket head at the string mounting position forms individual strings of the main string portion and the cross string portion of the racket head. The lockable grommets can adjust tension of each individual string to control tension and thus vibration in the entire racket head.

What is claimed is: 
     
         1 . A sports racket comprising:
 a racket body having a racket head, the racket head having a frame that has substantially rectangular face shape with appropriately rounded corners, the frame having a plurality of string mounting positions in a predetermined arrangement on the four sides of the rectangular face shape;   a racket handle affixed to the racket head;   a plurality of lockable grommets integrally disposed in the frame of the racket head, each of the plurality of grommets at a different one of the plurality of string mounting positions; and   at least one string mounted to the racket head at the plurality of string mounting positions to form individual strings of the main string portion and individual strings of the cross string portion of the racket head, wherein the plurality of lockable grommets can implement tension of each individual string of the main string portion and the cross string portion.   
     
     
         2 . The sports racket of  claim 1 , wherein the racket head that has more rounded corners and a shorter outer sides than known substantially rectangular sports rackets to provide greater strength, lighter weight and a larger sweet spot size than known sports rackets. 
     
     
         3 . The sports racket of  claim 1 , wherein the curved corners creates affected strings and unaffected strings, and wherein the affected strings can be made to vibrate at the same frequencies as the unaffected strings. 
     
     
         4 . The sports racket of  claim 1 , wherein all individual strings of the main string portion have equal frequencies. 
     
     
         5 . The sports racket of  claim 1 , wherein all individual strings of the cross string portion have equal vibration frequencies. 
     
     
         6 . The sports racket of  claim 1 , wherein each individual string also has a density and diameter, and wherein the tension, density and diameter of each individual string is chosen so that the individual strings of the main string portion and the individual strings of the cross string portion have equal vibration frequencies. 
     
     
         7 . The sports racket of  claim 1 , wherein the plurality of grommets lockable grommets enable the string tensions to be set to maintain the equal string vibration frequencies on the shorter strings within the rounded corners. 
     
     
         8 . The sports racket of  claim 1 , wherein each of the plurality of lockable grommets have a sleeve portion with an axial string passage, and wherein each of the plurality of lockable grommets provides a double securing of the individual string. 
     
     
         9 . The sports racket of  claim 1 , wherein the racket is made of a metallic material that is not tubular. 
     
     
         10 . The sports racket of  claim 9 , wherein the racket maintains narrow but strong corners, and controls vibrations. 
     
     
         11 . The sports racket of  claim 1 , wherein each of the plurality of lockable grommets is strong enough to secure each individual string with a tension up to 70 lbs. 
     
     
         12 . The sports racket of  claim 1 , wherein each of the plurality of lockable grommets enable implementation of a stringing protocol that alternates main and cross string tensioning, to sequentially eliminate any significant bowing of the frame during stringing. 
     
     
         13 . The sports racket of  claim 1 , wherein the frame has a two pairs of opposed sides that are very light but stable since the individual strings contribute to the stability of the frame. 
     
     
         14 . The sports racket of  claim 1 , wherein each of the plurality of lockable grommets enable the sweet spot to be enlarged by providing lower tensions on the selected individual strings near the sides of the frame. 
     
     
         15 . The sports racket of  claim 1 , further comprising an equivalent stringing mechanism in which all of the individual strings are tensioned simultaneously. 
     
     
         16 . The sports racket of  claim 1 , wherein the plurality of lockable grommets enable the precise setting of the desired tension on each individual string. 
     
     
         17 . The sports racket of  claim 1 , wherein each of the plurality of lockable grommets allow for individual string tension adjustment and individual string replacement. 
     
     
         18 . The sports racket of  claim 1 , wherein each of the plurality of lockable grommets provides at least a double clamp on the individual string. 
     
     
         19 . The sports racket of  claim 1 , wherein the double clamp provides a spread-out balanced force on the string. 
     
     
         20 . The sports racket of  claim 1 , wherein the frame is primarily made of carbon fiber, and wherein the frame has a face perimeter that contains an embedded metallic strip. 
     
     
         21 . The sports racket of  claim 1 , wherein the embedded metallic strip has metallic cylinders into which the plurality of grommets are placed. 
     
     
         22 . A sports racket comprising:
 a racket body having a racket head, the racket head having a frame that has substantially rectangular face shape with appropriately rounded corners and the area in the frame defining the racket face, the frame having a plurality of string mounting positions in a predetermined arrangement on the four sides of the rectangular face shape, the frame being made of a metal;   a plurality of lockable grommets integrally disposed in the frame of the racket head, each of the plurality of grommets at a different one of the plurality of string mounting positions; and   at least one string mounted to the racket head at the plurality of string mounting positions to form individual strings of the main string portion and the cross string portion of the racket head, wherein the plurality of lockable grommets adjust tension of the individual strings.   
     
     
         23 . The sports racket of  claim 22 , further comprising a stringing protocol that provides a sweet spot formed by some of the individual strings, wherein the sweet spot is nearly the entire racket face. 
     
     
         24 . A stringing protocol for a sports racket that provides means of compressing the grommet onto a string, the string protocol comprising:
 inserting the string sequentially through a central hole in a grommet, an external threaded crimping cylinder, and into and around a perpendicular tensioning cylinder, the grommet having a pair of opposed ends with one of the pair being an outward facing end, the threaded cylinder having inward facing concave conical indentation;   rotating the tensioning cylinder until the desired tension is given to the string.   rotating the threaded cylinder so that the conical indentation moves onto the outward facing end of the grommet so that both ends of the grommet clamp onto the string.   
     
     
         25 . The stringing protocol of  claim 24 , wherein the string is a plurality of strings, and wherein the stringing protocol can tension all of the strings simultaneously. 
     
     
         26 . The stringing protocol of  claim 24 , wherein the sports racket comprises:
 a racket body having a racket head, the racket head having a frame that has substantially rectangular face shape with appropriately rounded corners, the frame having a plurality of string mounting positions in a predetermined arrangement on the four sides of the rectangular face shape;   a racket handle affixed to the racket head;   a grommet integrally disposed in each one of the plurality of string mounting positions in the frame of the racket head; and   at least one string mounted to the racket head at the plurality of string mounting positions to form individual strings of the main string portion and individual strings of the cross string portion of the racket head, wherein each grommet in each of the plurality of string mounting positions can implement tension of each individual string of the main string portion and the cross string portion.   
     
     
         27 . The stringing protocol of  claim 26 , wherein the racket is strung using a stringing platform that has a tensioning cylinder for each individual string and a fixed structure that contains a threaded hole for each individual string. 
     
     
         28 . The stringing protocol of  claim 27 , wherein each threaded hole accommodates a threaded cylinder with an inner facing end that is a crimping tool and an outer end, and wherein, as the threaded cylinder is screwed into the threaded hole, the outer end of the threaded cylinder moves into the grommet hole and crimps that grommet. 
     
     
         29 . The stringing protocol of  claim 26 , wherein the racket is strung using a hand-held device that includes a tensioning cylinder and a perpendicular crimping cylinder, and wherein the perpendicular crimping cylinder can rotate onto one grommet to crimp the one grommet onto the individual string tensioned by the tensioning cylinder. 
     
     
         30 . The stringing protocol of  claim 24 , further comprising a plurality of grommets and a plurality of strings, wherein each string is tensioned by a separate tensioning cylinder, and wherein the tensioning cylinders are all turned simultaneously. 
     
     
         31 . The stringing protocol of  claim 30 , wherein the tensioning cylinders are all turned simultaneously using gears. 
     
     
         32 . The stringing protocol of  claim 31 , wherein the gears are located under a platform. 
     
     
         33 . The stringing protocol of  claim 30 , wherein each tensioning cylinder has a diameter that provides the individual string with the desired tension as the individual strings are tensioned.