Composite racquet with double tube head frame

Abstract

A sports racquet frame is built of a composite of laminations of fibrous material as impregnated by a thermosetting resin. The head section of the frame has an upper tube preferably disposed above the string bed plane and a lower tube preferably disposed below the string bed plane. A solid bridge of material integrally joins the upper tube to the lower tube. In a preferred embodiment the bridge is disposed radially exteriorly of the center line of the tubes, to maximize the length of string segments, which are strung to the bridge.

1 . A sports racquet, comprising: 
 a frame formed of a composite of plural laminations of fibrous material impregnated with a polymer;    the frame having an elongate head portion formed around and defining a string bed, the head section including a first tube which is elongate in the direction of elongation of the head portion, a second tube which is elongate in the direction of elongation of the head portion and disposed generally in parallel to the first tube, and a single bridge, elongate in the direction of elongation of the head portion, joining and spacing the first tube with and from the second tube, the bridge having no cavity which is elongate in said direction of elongation of the head portion.    
   
   
       2 . The racquet of  claim 1 , wherein the string bed substantially resides in a string bed plane, the first tube disposed above the plane, the second tube disposed below the plane, the plane intersecting the bridge.  
   
   
       3 . The racquet of  claim 1 , wherein the bridge is substantially perpendicular to the string bed plane.  
   
   
       4 . The racquet of  claim 1 , wherein the head section further includes an elongate single-tube subsection and an elongate double-tube subsection which includes said first and second tubes, the single tube subsection joined to the double-tube subsection end to end, the single-tube subsection being integrally formed with the double-tube subsection.  
   
   
       5 . The racquet of  claim 1 , wherein the head section further includes a plurality of fins formed at an angle to the string bed, to extend inwardly from the bridge and to span the first and second tubes.  
   
   
       6 . The racquet of  claim 5 , wherein string holes are formed at intervals in the bridge to receive string segments, the fins disposed at locations in between the string holes.  
   
   
       7 . The racquet of  claim 1 , wherein the fins are formed to be substantially perpendicular to the string bed.  
   
   
       8 . The racquet of  claim 1 , wherein the racquet is selected from the group consisting of tennis rackets, racquetball racquets, squash racquets and badminton racquets.  
   
   
       9 . A sports racquet, comprising: 
 a frame head portion defining and supporting a string bed, the string bed having a center and substantially disposed in a string bed plane;    the frame head portion being comprised of an endless wall of composite material, the composite material formed of a plurality of laminations of fibrous material as impregnated with a polymer, the endless wall having an outer portion relatively remote from the center of the string bed and an inner portion relatively near to the center of the string bed; and    the endless wall forming an upper tube, a lower tube and a single bridge joining the upper tube to the lower tube, the bridge spacing the upper tube from the lower tube in a depth direction orthogonal to the string bed plane, the outer portion of the endless wall being joined to the inner portion of the endless wall along the depth direction of the bridge.    
   
   
       10 . The sports racquet of  claim 9 , wherein at least one of said plurality of laminations of fibrous material has a fiber orientation that is neither parallel to a direction of elongation of the frame head portion nor perpendicular thereto, said at least one lamination being present in said outer portion of the endless wall and the inner portion of the endless portion, such that fibers in said at least one lamination in the outer portion will be disposed at an angle to fibers in said at least one lamination in the inner portion.  
   
   
       11 . The sports racquet of  claim 10 , wherein the angle is selected from the group consisting of ten degrees, 22 degrees, 45 degrees and 60 degrees.  
   
   
       12 . The sports racquet of  claim 9 , wherein the fibers comprise carbon.  
   
   
       13 . The sports racquet of  claim 9 , wherein the sports racquet is selected from the group consisting of racquetball racquets, tennis rackets, squash racquets and badminton racquets.  
   
   
       14 . A sports racquet, comprising: 
 a frame having a head portion defining and surrounding a strung area, the frame formed of a composite including plural laminations of fibrous material as impregnated with a polymer, a periphery of the head portion defining a theoretical maximum area across which unconstrained strings can be strung, an actual area across which unconstrained strings are strung being more than 91% of said theoretical maximum area.