Method and apparatus for the simultaneous centralized control of the yarn brakes of twist spindles of a two-for-one twisting machine

Abstract

A method and apparatus for the simultaneous centralized controlled adjustment of the braking force of yarn brakes of a plurality of twist spindles of a two-for-one twisting machine are provided, whereby each twist spindle is of the type having, in its hollow shaft, a yarn brake supported between two brake rings with one of the brake rings being rotatable in response to a downward axial pressure thereon in a manner such that the brake ring undergoes a discrete axial displacement to a new axial position. A support frame to which yarn balloon guides are mounted exerts a downward axial force such that the yarn balloon guides simultaneously exert downward axial pressure on the yarn intake conduits of the twist spindles which, in turn, effects axial displacement of the rotatable and axially adjustable brake ring on the yarn intake conduit of each twist spindle into new axial positions.

What I claim is:  
     
         1 . A method for the simultaneous centralized controlled adjustment of the braking force of capsule-like yarn brakes of a plurality of twist spindles of a two-for-one twisting machine, whereby each twist spindle includes a bullet-like brake arrangement disposed in the hollow shaft thereof having a capsule-like yarn brake supported between two brake rings disposed at an axial spacing from one another, one of the brake rings being rotatable in response to a downward axial pressure thereon in a manner such that the brake ring undergoes a discrete axial displacement to a new axial position at which the brake ring remains upon cessation of the downward axial pressure thereon, whereby each twist spindle includes a yarn intake conduit and has associated therewith a respective yarn balloon guide disposed above the yarn intake conduit, the method comprising: 
 on a support frame to which the yarn balloon guides are mounted and which is displaceable upwardly and downwardly parallel to the hollow axes of the twist spindles, exerting a downward axial force such that the yarn balloon guides mounted to the support frame simultaneously exert downward axial pressure on the yarn intake conduits of the twist spindles which, in turn, effects axial displacement of the rotatable and axially adjustable brake ring on the yarn intake conduit of each twist spindle into new axial positions, whereby a simultaneous adjustment of the braking force applied by the twist spindles to the yarn traveling therethough can be accomplished.    
     
     
         2 . An apparatus for simultaneously commonly adjusting the braking force of a plurality of capsule-like yarn brakes each disposed in a respective twist spindle of a two-for-one twisting machine, each twist spindle having a yarn brake supported by two axially spaced brake rings in the hollow shaft of the twist spindle, the one brake ring being rotatable in response to axial pressure thereon whereby the rotation of the brake ring effects a discrete axial movement of the brake ring into a new axial position at which the brake ring remains once the axial pressure thereon ceases, each twist spindle having a yarn intake conduit forming a portion of its hollow shaft, and the two-for-one twisting machine having a plurality of yarn balloon guides each associated with a respective twist spindle for guiding the formation of a yarn balloon relative thereto, the apparatus comprising: 
 means for mounting to the yarn intake conduit of each respective twist spindle the respective brake ring of the twist spindle, the brake ring being that brake ring whose rotation is translated into axial displacement of the brake ring; and    a support frame movably mounted on the two-for-one twisting machine for movement upwardly and downwardly generally parallel to the axes of the twist spindles, the plurality of yarn balloon guides being mounted to the support frame such that each of the yarn balloon guides exerts, simultaneously with the other yarn balloon guides, a downward pressure on the yarn intake conduit of the respective associated twist spindle, whereupon simultaneous downward axial pressure is thereby applied to the brake rings mounted to the yarn intake conduits of the twist spindles in a manner which causes the one brake rings thereof to rotate and undergo the associated axial displacement.    
     
     
         3 . An apparatus according to  claim 2  and further comprising a plurality of adjustment units each associated with a respective twist spindle and a plurality of radially projecting detents each mounted in the hollow shaft of a respective twist spindle and projecting radially inwardly toward the respective associated adjustment unit, each adjustment unit having an annular upper toothed rim and an annular lower toothed rim, the upper toothed rim having a plurality of downwardly oriented teeth distributed around its circumference such that downwardly opening slots are formed between adjacent teeth and the lower toothed rim having a plurality of upwardly oriented teeth distributed around its circumference such that upwardly opening slots are formed between adjacent teeth, the teeth of the upper toothed rim and the teeth of the lower toothed rim, in response to the downward axial pressure on the yarn intake conduit, cooperating with one another to engage the respective radially inwardly projecting detent such that the adjustment unit is guided by the stationary detent to rotate in a given rotational direction relative to the stationary detent, the apexes of the teeth of the upper toothed rim being angularly offset from the apexes of the teeth of the lower toothed rim, and respective flank surfaces of the teeth of the upper toothed rim and respective flank surfaces of the teeth of the lower toothed rim being angled at a selected one of an upward angle and a downward angle relative to the given rotation direction such that the teeth of the upper toothed rim and the teeth of the lower toothed rim guide the rotational movement of the adjustment unit relatively along the stationary detent in a manner such that the stationary detent is unseated from a respective notch between the teeth of the lower toothed rim and is subsequently seated in another notch between the teeth of the lower toothed rim upon the cessation of the downward axial pressure on the yarn intake conduit.  
     
     
         4 . An apparatus according to  claim 3 , wherein those flanks of the teeth of the upper and lower toothed rims which are angled upwardly relative to the rotational direction extend substantially in the axial direction.  
     
     
         5 . An apparatus according to  claim 3 , wherein the angled flank surfaces of the upper and lower rims form an angle of approximately 45° with the rotational direction.  
     
     
         6 . An apparatus according to  claim 2 , wherein a spring is provided which operates against the lower toothed rim of the adjustment unit so as to bias the adjustment unit axially upwardly, whereby the upward axial bias of the adjustment unit effects seating of the detent in the next notch of the lower toothed rim upon the cessation of the downward axial pressure on the yarn intake conduit.  
     
     
         7 . An apparatus according to  claim 2 , wherein each of the toothed rims is configured as a lower component freely rotatable relative to the other portion of the adjustment unit, the toothed rims being non-adjustable in the axial direction.  
     
     
         8 . An apparatus according to  claim 2 , wherein the yarn balloon guides are configured as ball-shaped yarn balloon guides which are each centered on the yarn intake conduit of the respective associated twist spindle.