Synthetic strings for racket and method for making same

Abstract

Synthetic string, particularly for tennis rackets. According to the invention, surface dimples are formed on the string after the string is produced. A device for forming the dimples on the string is also disclosed. The invention thereby facilitates stringing, provides a better grip of the ball on the racket face, and provides a novel appearance.

1 - 6 . (canceled)  
   
   
       7 . A synthetic string comprising: 
 a plurality of multifilament threads twisted to form a synthetic string; and    a plurality of surface dimples on an external surface of the synthetic string, the surface dimples arranged on opposed sides of the synthetic string.    
   
   
       8 . The synthetic string according to  claim 7 , wherein the synthetic string has a diameter of about 1.40 millimeters and each surface dimple has a depth of about 0.05 millimeters.  
   
   
       9 . The synthetic string according to  claim 7 , wherein adjacent surface dimples on each side of the synthetic string are spaced apart by about 4 millimeters.  
   
   
       10 . The synthetic string according to  claim 9 , wherein the surface dimples are staggered to form diametrically opposed surface dimples on the opposed sides.  
   
   
       11 . The synthetic string according to  claim 7 , wherein the multifilament threads comprise multifilament polyamide threads integrated in a polyurethane matrix.  
   
   
       12 . The synthetic string according to  claim 7 , wherein each of the plurality of multifilament threads comprise eleven multifilament threads, each thread comprising 140 filaments wherein each filament has a diameter of about 28 microns.  
   
   
       13 . The synthetic string according to  claim 7 , wherein the synthetic string presents a resistance to breaking that is greater than about 80 daNs and a breaking elongation of about 25 percent.  
   
   
       14 . The string according to  claim 7 , wherein the multifilament threads are twisted at approximately 80 turns/meter.  
   
   
       15 . A device for providing a plurality of dimples on a synthetic multifilament string suited for a tennis racket, the device comprising: 
 four wheels arranged in two pairs, each pair of wheels comprising a toothed wheel and a guide wheel operable to pass the synthetic multifilament string between the wheels of each pair and provide a plurality of dimples on the string.    
   
   
       16 . The device according to  claim 15 , wherein the guiding wheel of at least one pair of wheels is equipped with a guiding recess.  
   
   
       17 . The device according to  claim 15 , wherein the toothed wheel of each pair of wheel is staggered so as form diametrically opposed dimples on the string.