Autoleveller draw frame, method for operating an autoleveller draw frame, and method for converting an autoleveller draw frame

Abstract

An autoleveller draw frame includes a drafting system having a plurality of roller combinations. A drive unit configured with the plurality of roller combinations has a main motor that drives a first roller combination at a constant main rotational speed. A regulating motor regulates a rotational speed of a second roller combination wherein, due to the regulation, the rotational speed of the second roller combination is changeable from a basic rotational speed into an autolevelling speed. The basic rotational speed depends on the main rotational speed and the autolevelling speed is independent of the main rotational speed, wherein the drafting of the fibrous web is adjustable. The regulating motor is drive-independent of the main motor to drive the second roller combination at the autolevelling speed according to an electrical signal that is based on the main rotational speed.

1 - 13 : (canceled) 
     
     
         14 . An autoleveller draw frame, comprising:
 a drafting system having a plurality of roller combinations situated one behind the other for drafting a fibrous web from one or more slivers;   a drive unit configured with the plurality of roller combinations, the drive unit comprising:
 a main motor that drives a first of the roller combinations at a constant main rotational speed; 
 a regulating motor that regulates a rotational speed of a second of the roller combinations, wherein, due to the regulation, the rotational speed of the second roller combination is changeable from a basic rotational speed into an autolevelling speed, the basic rotational speed depending on the main rotational speed and the autolevelling speed being independent of the main rotational speed, wherein the drafting of the fibrous web is adjustable; and 
 the regulating motor being drive-independent of the main motor to drive the second roller combination independently of the main motor at the autolevelling speed according to an electrical signal that is based on the main rotational speed. 
   
     
     
         15 . The autoleveller draw frame according to  claim 14 , wherein the drive unit comprises a speed sensor that detects the main rotational speed of the first roller combination or rotation of the main motor. 
     
     
         16 . The autoleveller draw frame according to  claim 15 , wherein the drive unit comprises a transmission unit that transforms a signal from the speed sensor into a signal for the basic rotational speed of the second roller combination. 
     
     
         17 . The autoleveller draw frame according to  claim 14 , further comprising a pair of scanning rollers that detect a thickness of the slivers entering the drafting system. 
     
     
         18 . The autoleveller draw frame according to  claim 17 , further comprising a specification unit electrically connected to the pair of scanning rollers, the specification unit setting a superimposition speed for the basic rotational speed based on the thickness of the slivers. 
     
     
         19 . The autoleveller draw frame according to  claim 18 , wherein the drive unit further comprises a control unit configured with the regulating motor, the control unit calculating the autolevelling speed from the superimposition speed and the basic rotational speed. 
     
     
         20 . The autoleveller draw frame according to  claim 19 , wherein the autolevelling speed is transmitted to the regulating motor as an electrical signal. 
     
     
         21 . The autoleveller draw frame according to  claim 14 , wherein the main motor comprises an induction motor and the regulating motor comprises a reluctance motor. 
     
     
         22 . A method for operating an autoleveller draw frame, wherein the autoleveller draw frame includes:
 a drafting system having a plurality of roller combinations situated one behind the other for drafting a fibrous web from one or more slivers;   a drive unit configured with the plurality of roller combinations, the drive unit comprising:
 a main motor that drives a first of the roller combinations at a constant main rotational speed; 
 a regulating motor that regulates a rotational speed of a second of the roller combinations, wherein, due to the regulation, the rotational speed of the second roller combination is changeable from a basic rotational speed into an autolevelling speed, the basic rotational speed depending on the main rotational speed and the autolevelling speed being independent of the main rotational speed, wherein the drafting of the fibrous web is adjustable; and 
   the method comprising driving the regulating motor independent of the main motor to drive the second roller combination independently of the main motor at the autolevelling speed on the basis of an electrical signal that is based on the main rotational speed.   
     
     
         23 . A method for converting an autoleveller draw frame from an initial configuration to a final configuration, the initial configuration including:
 a drafting system having a plurality of roller combinations situated one behind the other for drafting a fibrous web from one or more slivers;   a drive unit configured with the plurality of roller combinations, the drive unit including:
 a main motor for driving a first of the plurality of roller combinations at a constant main rotational speed; 
 a differential gear that transmits a rotational speed of the main motor to a second of the plurality of roller combinations such a basic rotational speed of the second roller combination depends on the main rotational speed of the first roller combination; and 
 a superimposition motor that superimposes a superimposition speed on the basic rotational speed by means of the differential gear such that, due to the superimposition, a rotational speed of the second roller combination is changeable from the basic rotational speed into an autolevelling speed; 
   the method comprising:   removing the differential gear from the drive unit;   replacing the superimposition motor with a regulating motor that is drive-independent of the main motor; and   wherein the regulating motor drives the second roller combination independently of the main motor at the autolevelling speed on the basis of an electrical signal that depends on the main rotational speed.   
     
     
         24 . The method for converting an autoleveller draw frame according to  claim 23 , wherein at least one drive element or output element of the differential gear is reused as a transmission element of the regulating motor. 
     
     
         25 . The method for converting an autoleveller draw frame according to  claim 23 , further comprising removing a mechanical or electromagnetic brake of the drive unit.