Yarn Braking Body

Abstract

A yarn braking body is a flexible frustocone coat made from plastic material and has a circumferentially continuous braking surface which is defined by a part of the inner surface of the frustocone coat. The yarn braking body has a circumferentially continuous support part at the small diameter end. The support part is spherical and one piece with the frustocone coat and is made from the plastic material of the yarn braking body such that the centre of the sphere lies in the axis of the frustocone coat which axis is prolonged beyond the large diameter end.

1 . Yarn braking body for a yarn feeding device, in particular for a knitting yarn feeding device, the yarn braking body being a flexible frustocone coat made from plastic material and having a large diameter end of substantially circular form, a small diameter end of substantially circular form and a circumferentially continuous braking surface defined by a part of the inner surface of the frustocone coat, and having a circumferentially continuous support part at the small diameter end, wherein the support part is integrally made spherical and in one piece with the frustocone coat from the plastic material of the yarn braking body such that the center of the sphere lies in the axis of the frustocone coat which axis is prolonged beyond the large diameter end.  
   
   
       2 . Yarn braking body as in  claim 1 , wherein the wall thickness of the yarn braking body is continuously the same in the frustocone coat and in the spherical support part.  
   
   
       3 . Yarn braking body as in  claim 1 , wherein the sphere radius of the spherical support part is between 30%,and 60%, preferably about 43%, of the diameter of the large diameter end of the frustocone coat.  
   
   
       4 . Yarn braking body as in  claim 2 , wherein the wall thickness is smaller than 1.0 mm, preferably is between 0.2 mm and 0.5 mm.  
   
   
       5 . Yarn braking body as in  claim 1 , wherein the cone angle of the frustocone coat amounts to between about 100° and 135°.  
   
   
       6 . Yarn braking body as in  claim 1 , wherein the plastic material is a thermal plastic material, e.g. polyester, PET or PVC.  
   
   
       7 . Yarn braking body as in  claim 1 , wherein the yarn braking body is shaped by, preferably thermal, vacuum shaping of a blank, preferably of a planar blank.  
   
   
       8 . Yarn braking body as in  claim 1 , wherein the spherical support part is a stepless continuation of the frustocone coat.  
   
   
       9 . Yarn braking body as in  claim 1 , wherein the height of the spherical support part measured in the direction of the axis of the frustocone coat measures between about 15% to 35%, preferably less than 30%, of the height of the yarn braking body.  
   
   
       10 . Yarn braking body as in  claim 1 , wherein the spherical support part forms the small diameter end of the frustocone coat.  
   
   
       11 . Yarn braking body as in  claim 1 , wherein the outer diameter of the spherical support part amounts to about 2.5 to 4.5 fold of the inner diameter of the small diameter end.  
   
   
       12 . Yarn braking body as in  claim 1 , wherein the outer diameter of the spherical support part amounts to about 25% to 45% of the diameter of the large diameter end.  
   
   
       13 . Yarn braking body as in  claim 1 , wherein the inner surface of the frustocone coat has a smoothness at least in the region of the braking surface corresponding to a polished surface.