Drafting device, spinning station and method

Abstract

A drafting device for a textile machine, in particular an air-jet spinning machine, wherein the drafting device can have a plurality of roller pairs which can be driven differently from one another. The roller pairs can be designed and arranged to guide a sliver between a top roller and a bottom roller of the roller pairs during their rotational operation in order to stretch the sliver. The drafting device can be designed and configured to carry out a piecing process after the sliver has been severed in the drafting device. In order to optimize a spinning process, it is provided that the drafting device is designed and configured to engage at least two roller pairs via their drive in a defined manner during the piecing process.

1 . A drafting device for a textile machine comprising:
 a plurality of roller pairs which can be driven differently from one another, wherein the plurality of roller pairs are designed and arranged to guide a sliver between a top roller and a bottom roller of the plurality of roller pairs during a rotational operation thereof in order to stretch the sliver;   wherein the drafting device is designed and configured to carry out a piecing method after severing of the sliver in the drafting device; and   wherein the drafting device is designed and configured to engage at least two roller pairs of the plurality of roller pairs in a defined manner via a drive thereof in the piecing method.   
     
     
         2 . The drafting device according to  claim 1 , wherein the at least two roller pairs for a defined engagement are selected from the following:
 an input roller pair;   a center roller pair; and/or   an apron roller pair.   
     
     
         3 . The drafting device according to  claim 1 , further including a spinneret designed and configured to assume at least one cleaning position. 
     
     
         4 . The drafting device according to  claim 1 , wherein the drafting device is designed and configured to sever the sliver by a coordinated engagement of at least one roller pair of the plurality of roller pairs. 
     
     
         5 . The drafting device according to  claim 1 , wherein the drafting device is designed and configured to coordinate severing of the sliver with a transfer of a spinneret to a cleaning position via a coordinated engagement of at least one roller pair of the plurality of roller pairs. 
     
     
         6 . The drafting device according to  claim 1 , wherein the drafting device is designed and configured to specifically adjust at least one process parameter for driving at least one of the roller pairs of the plurality of roller pairs over a defined period of time. 
     
     
         7 . The drafting device according to  claim 1 , wherein the drafting device is designed and configured during a piecing ramp to form at least two support points in a ramp-up profile for a defined driving of at least one of the roller pairs of the plurality of roller pairs. 
     
     
         8 . The drafting device according to  claim 1 , wherein the drafting device is designed and configured to maintain a defined temperature of a drive of one of the roller pairs of the plurality of roller pairs and/or of a rubber lining of rollers of one of the roller pairs of the plurality of roller pairs. 
     
     
         9 . A spinning station comprising:
 at least one spinneret;   at least one thread end preparer; and   at least one thread take-off;   wherein the at least one spinneret and the at least one thread end preparer are arranged and designed to initiate piecing;   wherein the at least one thread take-off is arranged and designed to remove a thread from the at least one spinneret after a spinning process; and   wherein at least one drivable roller pair of the plurality of roller pairs of the drafting device according to  claim 1  is engaged in a coordinated manner via the drive of at least one roller pair of the plurality of roller pairs.   
     
     
         10 . The spinning station according to  claim 9 , wherein the at least one thread take-off is designed and configured to be engaged along with the at least one roller pair in a coordinated manner, wherein a ramp-up profile of the at least one roller pair has a piecing ramp with at least two support points. 
     
     
         11 . The spinning station according to  claim 9 , wherein:
 the at least one spinneret is designed and configured to assume at least an operating position and a cleaning position different therefrom; and   the at least one thread end preparer is designed and configured to at least unravel a thread end by a compressed air supply.   
     
     
         12 . A method comprising at least one of the steps of:
 severing a sliver by coordinated engagement of at least one roller pair of the drafting device according to  claim 1 ;   piecing by coordinated engagement of the at least two roller pairs of the drafting device;   piecing by coordinated engagement of at least one thread take-off of a spinning station, the spinning station comprising at least one spinneret, at least one thread end preparer and the at least one thread take-off, wherein the at least one spinneret and the at least one thread end preparer are arranged and designed to initiate piecing, wherein the at least one thread take-off is arranged and designed to remove a thread from the spinneret after a spinning process, and wherein at least one drivable roller pair of the drafting device is engaged in a coordinated manner via the drive of the at least two roller pairs; and   spinning the thread comprising a coordinated engagement of a thread take-off and the at least one roller pair of the drafting device.   
     
     
         13 . A control apparatus designed and configured to carry out the method according to  claim 12 . 
     
     
         14 . A textile machine comprising at least one of the following:
 a drafting device for a textile machine having a plurality of roller pairs which can be driven differently from one another, wherein the roller pairs are designed and arranged to guide a sliver between a top roller and a bottom roller of the roller pairs during their rotational operation in order to stretch the sliver, wherein the drafting device is designed and configured to carry out a piecing method after severing of the sliver in the drafting device, and wherein the drafting device is designed and configured to engage at least two roller pairs in a defined manner via their drive in the piecing method;   a spinning station comprising: at least one spinneret, at least one thread end preparer, and at least one thread take-off, wherein the at least one spinneret and the at least one thread end preparer are arranged and designed to initiate piecing,   wherein the at least one thread take-off is arranged and designed to remove a thread from the at least one spinneret after a spinning process, and wherein at least one drivable roller pair of a drafting device is engaged in a coordinated manner via the drive of the roller pairs; and   a control apparatus designed and configured to carry out a method comprising at least one of the steps of:
 severing a sliver by coordinated engagement of at least one roller pair, wherein the drafting device has a plurality of roller pairs which can be driven differently from one another, wherein the roller pairs are designed and arranged to guide the sliver between a top roller and a bottom roller of the respective roller pairs during their rotational operation in order to stretch the sliver, and wherein the drafting device is designed and configured to carry out a piecing method after severing of the sliver in the drafting device, and wherein the drafting device is designed and configured to engage at least two roller pairs in a defined manner via their drive in the piecing method; 
 piecing by coordinated engagement of at least two roller pairs of the drafting device; 
 piecing by coordinated engagement of at least one thread take-off of a spinning station in order to return a thread end; and 
 spinning a thread comprising a coordinated engagement of a thread take-off and the at least one roller pair of the drafting device according to  claim 1 . 
   
     
     
         15 . A computer program product designed to perform a method comprising at least one of the steps of:
 severing a sliver by coordinated engagement of at least one roller pair of a drafting device, wherein the drafting device has a plurality of roller pairs which can be driven differently from one another, wherein the roller pairs are designed and arranged to guide a sliver between a top roller and a bottom roller of the roller pairs during their rotational operation in order to stretch the sliver, wherein the drafting device is designed and configured to carry out a piecing method after severing of the sliver in the drafting device, and wherein the drafting device is designed and configured to engage at least two roller pairs in a defined manner via their drive in the piecing method;   piecing by coordinated engagement of at least two roller pairs of the drafting device; and   piecing by coordinated engagement of the at least one thread take-off of the spinning station according to  claim 9 .