Radial braiding machine, braiding ring, flat braid and method of producing the flat braid

Abstract

A radial braiding machine includes a bobbin gear through which stationary yarns and braiding yarns are fed, a braiding ring through which the stationary yarns and braiding yarns are guided, and at least one transport device for transporting a core to be over-braided. The braiding ring has a non-round internal cross-section when projected onto a yarn outlet plane spanned by the bobbin gear. A braiding ring, a flat braid and a method of producing the flat braid are also provided.

1 . A radial braiding machine, comprising:
 a bobbin gear through which stationary yarn and braiding yarn are fed, said bobbin gear spanning a first yarn outlet plane;   a braiding ring through which the stationary and braiding yarns are guided, said braiding ring having a non-round internal cross section when projected onto said first yarn outlet plane;   a core to be over-braided; and   at least one transportation device for transporting said core.   
     
     
         2 . The braiding machine according to  claim 1 , wherein said braiding ring has an oval internal cross section when projected onto said first yarn outlet plane. 
     
     
         3 . The braiding machine according to  claim 1 , wherein:
 said at least one transportation device defines a transport direction;   a second plane is parallel to said first yarn outlet plane;   said braiding ring has a front side yarn diverter diverting the stationary and braiding yarns; and   said yarn diverter protrudes in regions from said first yarn outlet plane or from said second plane in a direction opposite to said transport direction.   
     
     
         4 . The braiding machine according to  claim 3 , wherein said braiding ring is pivotable in the braiding machine about at least one of first and second mutually orthogonal pivot axes causing said yarn diverter to protrude to different extents at points of intersection of said braiding ring with at least one of said pivot axes. 
     
     
         5 . The braiding machine according to  claim 4 , wherein said yarn diverter protrudes with respect to said first yarn outlet plane at said points of intersection with said first pivot axis by distances A 1  and A 2 , and at said points of intersection with said second pivot axis S 2  by distances A 3  and A 4 , where A 1 ≦A 2 <A 3 <A 4 . 
     
     
         6 . In a radial braiding machine including a bobbin gear through which stationary yarn and braiding yarn are fed, a core to be over-braided and at least one transportation device for transporting the core, the improvement comprising:
 a braiding ring through which the stationary and braiding yarns are guided;   said braiding ring having a non-round internal cross section when projected onto a first yarn outlet plane spanned by the bobbin gear; and   said braiding ring having a front side yarn diverter diverting the stationary and braiding yarns and spanning an imaginary surface being curved at least in regions.   
     
     
         7 . The improvement according to  claim 6 , wherein said braiding ring has a non-circular or elliptical inner contour. 
     
     
         8 . The improvement according to  claim 7 , wherein said inner contour encompasses first and second intersecting diameter axes, and said yarn diverter protrudes further at points of intersection with said second diameter axis than at points of intersection with said first diameter axis. 
     
     
         9 . A flat braid obtained by over-braiding a core using a radial braiding machine with a braiding ring through which yarns are guided by a bobbin gear, the flat braid comprising:
 stationary yarns extending in a longitudinal direction of the braid, each of said stationary yarns being disposed at a distance from a respective adjacent stationary yarn;   braiding yarns being interwoven with said stationary yarns and extending at an oblique angle to said stationary yarns, said braiding yarns following a course differing from an ideal, straight course of a nominal layer by an angle of twist;   said angle of twist being at most +/−3° and having characteristics of being obtained by:
 influencing a position and a time of deposition of said stationary and braiding yarns on the core by modifying the braiding ring from a circular shape taking into consideration a shape of the core; 
 providing the braiding ring with an internal cross section having a non-round shape when projected onto a yarn outlet plane being spanned by the bobbin gear; and 
 providing the braiding ring with an inner contour being at a different distance from an outer contour of the core to be over-braided. 
   
     
     
         10 . The flat braid according to  claim 9 , wherein said distances between said stationary yarns have an average value with a standard deviation of at most 5%. 
     
     
         11 . The flat braid according to  claim 9 , wherein the flat braid has characteristics of being obtained by forming or mounting the braiding ring having a front side yarn diverter diverting the yarns and protruding to a different extent over a plane being parallel to the yarn outlet plane. 
     
     
         12 . The flat braid according to  claim 9 , wherein the flat braid has characteristics of being obtained by using a non-round core having different cross-sectional dimensions with a maximum height and a maximum width and providing the braiding ring with an internal cross section differing from a circular shape when projected onto the yarn outlet plane and providing a distance thereof from the core at a position of a maximum cross-sectional dimension of the core being smaller than a distance at a position of a minimum cross-sectional dimension of the core. 
     
     
         13 . The flat braid according to  claim 9 , wherein the flat braid has characteristics of being obtained by using a non-round core having different cross-sectional dimensions of a maximum height and a maximum width, and a front side yarn diverter of the braiding ring protruding further at positions of a maximum cross-sectional dimension of the core than at positions of a minimum cross-sectional dimension of the core. 
     
     
         14 . The flat braid according to  claim 9 , wherein the flat braid has characteristics of being obtained by at least one of using or mounting a braiding ring having a front side yarn diverter protruding to a different extent at positions on both sides of at least one of a maximum or a minimum cross-sectional dimension of the core. 
     
     
         15 . The flat braid according to  claim 9 , wherein the flat braid has characteristics of being obtained by mounting the braiding ring in at least one of a tilted or pivoted manner relative to the yarn outlet plane. 
     
     
         16 . A method of producing a flat braid by over-braiding a core using a radial braiding machine having a braiding ring through which yarns are guided by a bobbin gear, the method comprising the following steps:
 providing stationary yarns extending in a longitudinal direction of the braid, each of the stationary yarns being disposed at a distance from a respective adjacent stationary yarn;   interweaving braiding yarns with the stationary yarns and extending the braiding yarns at an oblique angle to the stationary yarns, the braiding yarns following a course differing from an ideal, straight course of a nominal layer by an angle of twist; and   setting the angle of twist to be at most +/−3° by:
 influencing a position and a time of deposition of the stationary and braiding yarns on the core by modifying the braiding ring from a circular shape taking into consideration a shape of the core; 
 providing the braiding ring with an internal cross section having a non-round shape when projected onto a yarn outlet plane being spanned by the bobbin gear; and 
 providing the braiding ring with an inner contour being at a different distance from an outer contour of the core to be over-braided. 
   
     
     
         17 . The method according to  claim 16 , which further comprises providing the distances between the stationary yarns with an average value having a standard deviation of at most 5%. 
     
     
         18 . The method according to  claim 16 , which further comprises forming or mounting the braiding ring with a front side yarn diverter diverting the yarns and protruding to a different extent over a plane being parallel to the yarn outlet plane. 
     
     
         19 . The method according to  claim 16 , which further comprises using a non-round core having different cross-sectional dimensions with a maximum height and a maximum width and providing the braiding ring with an internal cross section differing from a circular shape when projected onto the yarn outlet plane and providing a distance thereof from the core at a position of a maximum cross-sectional dimension of the core being smaller than a distance at a position of a minimum cross-sectional dimension of the core. 
     
     
         20 . The method according to  claim 16 , which further comprises providing a non-round core having different cross-sectional dimensions of a maximum height and a maximum width, and a front side yarn diverter of the braiding ring protruding further at positions of a maximum cross-sectional dimension of the core than at positions of a minimum cross-sectional dimension of the core. 
     
     
         21 . The method according to  claim 16 , which further comprises at least one of using or mounting the braiding ring to have a front side yarn diverter protruding to a different extent at positions on both sides of at least one of a maximum or a minimum cross-sectional dimension of the core. 
     
     
         22 . The method according to  claim 16 , which further comprises mounting the braiding ring in at least one of a tilted or pivoted manner relative to the yarn outlet plane.