Ball game racquet, especially tennis racquet

Abstract

The ball sport or ball game racquet, in particular tennis racquet, having a racquet frame for holding stringing and a racquet shaft extending from the racquet frame and having one racquet grip, wherein the racquet frame and the racquet shaft both are formed from a hollow frame profile with a plurality of walls. In at least one of the walls of the racquet frame and/or of the racquet shaft, at least one spacing layer is provided at least in some sections for increasing the stability of the ball sport racquet.

1 . A ball sport or ball game racquet, comprising a racquet frame for holding the stringing and with a shaft extending from the racquet frame and a racquet grip, 
 wherein the racquet frame and the racquet shaft both feature a hollow frame profile consisting of a plurality of walls or wall sections, and    wherein at least one of the walls or wall sections of the racquet frame and/or of the racquet shaft features at least in some sections at least one spacing layer for increasing the stability of the ball sport racquet.    
   
   
       2 . The racquet according to  claim 1 , wherein the hollow frame profile of the racquet frame, the racquet shaft, or both the racquet frame and the racquet shaft, feature one upper and lower wall or wall sections and that at least one spacing layer is provided in the upper and/or lower wall or wall section.  
   
   
       3 . The racquet according to  claim 1 , wherein the hollow frame profile of the racquet frame, the racquet shaft, or both the racquet frame and the racquet shaft, feature one upper and lower wall or wall sections and that at least one spacing layer is only provided in the upper and/or lower wall or wall section.  
   
   
       4 . The racquet according to  claim 1 , wherein the walls of the racquet frame, the racquet shaft, or both the racquet frame and the racquet shaft, comprise prepreg layers or windings of prepreg material.  
   
   
       5 . The racquet according to  claim 4 , wherein the spacing layer is provided between at least two prepreg layers of the walls or wall sections.  
   
   
       6 . The racquet according to  claim 4 , wherein the spacing layer is provided between windings of prepreg material of the walls or wall sections.  
   
   
       7 . The racquet according to  claim 1 , wherein the walls or wall sections located away from a level of the stringing or being distanced from the stringing comprise the spacing layer.  
   
   
       8 . The racquet according to  claim 1 , wherein the spacing layer extends over at least two connecting sections between the racquet frame and the racquet shaft.  
   
   
       9 . The racquet according to  claim 1 , wherein the at least one spacing layer is provided at least in some sections in the hollow frame profile of a throat of the ball sport racquet.  
   
   
       10 . The racquet according to  claim 1 , wherein the spacing layer is made of a material with a honeycomb structure.  
   
   
       11 . The racquet according to  claim 1 , wherein the spacing layer is made of a foam material.  
   
   
       12 . The racquet according to  claim 1 , wherein the spacing layer is made of a material with a density of less than 1.9 g/cm 3  or with a compressive strength greater than 8.0×10 5  N/m 2 .  
   
   
       13 . The racquet according to  claim 1 , wherein the spacing layer is made of a material with a low volume weight.  
   
   
       14 . The racquet according to  claim 7 , wherein the walls or wall sections located away from the level of the stringing or being distanced from the stringing are fattened.  
   
   
       15 . The racquet according to  claim 1 , wherein the first and second prepreg layers are each formed by at least one winding of the prepreg material.  
   
   
       16 . A blow molding method for manufacturing a hollow frame profile for a ball sport or ball game racquet, comprising the following steps: 
 covering a production tube with at least one first prepreg layer;    application of at least one spacing layer on at least one upper and/or lower section of the first prepreg layer;    covering the at least first prepreg layer and the at least one spacing layer with at least one second prepreg layer;    pressing the at least first and second prepreg layer together with the integrated at least one spacing layer under application of heat to manufacture a hollow frame profile consisting of the at least one upper and lower wall or wall section.    
   
   
       17 . The method according to  claim 16 , wherein the at least one spacing layer is applied to at least one first prepreg layer forming one upper and/or lower wall.  
   
   
       18 . The method according to  claim 16 , wherein the at least one first spacing layer is applied to at least one first prepreg layer at a position forming an upper wall or wall section of the hollow frame profile and at least one second spacing layer is applied to said at least one first prepreg layer at a position forming an lower wall or wall section of the hollow frame profile, said at least one first and second spacing layers being distanced from another such that the hollow frame profile comprises inner and outer walls or wall sections without a spacing layer in between the upper and lower walls or wall sections.  
   
   
       19 . The method according to  claim 16 , wherein the first and second prepreg layers are each formed by at least one winding of the prepreg material.  
   
   
       20 . The method according to  claim 16 , wherein the at least one spacing layer is applied in the area of a throat of the ball sport racquet.