Yarn twist retention member on an open-end spinning machine

Abstract

The invention relates to a yarn ( 2 ) twist retention ( 1 ) on an open-end spinning machine comprising a part of a wall of a bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ), this section of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) on the yarn ( 2 ) twist retention member being provided with at least one yarn ( 2 ) twist retaining means. The yarn ( 2 ) twist retention means is made as a longitudinal groove ( 8 ) in a part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ), the walls ( 80 ) of the longitudinal groove ( 8 ) being situated symmetrically to each other along the longitudinal symmetry plane of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ).

1 . A yarn twist retention member on an open-end spinning machine comprising a part of a wall of a bent yarn delivery channel forming the inner side of the bent section of the bent yarn delivery channel ( 5 ), this section of the wall of the bent yarn delivery channel on the yarn twist retention member being provided with at least one yarn twist retaining means, characterized by that the yarn ( 2 ) twist retention means is made as a longitudinal groove ( 8 ) in a part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ), the walls ( 80 ) of the longitudinal groove ( 8 ) being situated symmetrically to each other along the longitudinal symmetry plane of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ).  
     
     
         2 . A yarn twist retention member as claimed in  claim 1 , characterized by that the longitudinal groove ( 8 ) made in the part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ) has the profile of the letter “V”.  
     
     
         3 . A yarn twist retention member as claimed in  claim 1 , characterized by that each of the walls ( 80 ) of the longitudinal groove ( 8 ) made in the part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ) has the profile consisting of a pair of mutually inclined sections ( 81 ).  
     
     
         4 . A yarn twist retention member as claimed in  claim 1 , characterized by that the profile of the walls ( 80 ) of the longitudinal groove ( 8 ) made in the part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ) is a convex one.  
     
     
         5 . A yarn twist retention member as claimed in  claim 1 , characterized by that the profile of the walls ( 80 ) of the longitudinal groove ( 8 ) made in the part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ) is a concave one.  
     
     
         6 . A yarn twist retention member as claimed in any of  claims 1  to  5 , characterized by that the walls ( 80 ) of the longitudinal groove ( 8 ) made in the part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ) have a surface roughness between R a  16 and R a  0,1.  
     
     
         7 . A yarn twist retention member as claimed in  claim 6 , characterized by that the walls ( 80 ) of the longitudinal groove ( 8 ) made in the part of the wall of the bent yarn ( 2 ) delivery channel ( 5 )) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ) have at least two different values of surface roughness R a .  
     
     
         8 . A yarn twist retention member as claimed in  claim 6 , characterized by that the walls ( 80 ) of the longitudinal groove ( 8 ) made in the part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ) have at their width portions adjacent to the bottom ( 82 ) of the longitudinal groove ( 8 ) a surface roughness R a  superior to the surface roughness R a  of the portions more distant from the bottom ( 82 ) of the longitudinal groove ( 8 ).  
     
     
         9 . A yarn twist retention member as claimed in  claim 6 , characterized by that the surface roughness R a  of the walls ( 80 ) of the longitudinal groove ( 8 ) in the part of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section ( 50 ) of the bent yarn ( 2 ) delivery channel ( 5 ) is superior to that of the wall of the bent yarn ( 2 ) delivery channel ( 5 ) forming the inner side ( 501 ) of the bent section of the bent yarn ( 2 ) delivery channel ( 5 ).