Method and apparatus for the regulation of the warp let-off a weaving machine

Abstract

A method and an apparatus for the regulation of the warp let-off of a weaving machine is proposed, in that a desired speed of rotation (S D ) is predetermined for a warp beam ( 2 ), in that a warp tension (K) of the warp threads ( 3 ) which are given off by the warp beam ( 2 ) is determined, in that the warp tension (K) is weighted with a weighting function (G) and in this manner a weighted warp tension (K G ) is determined, in that a corrected desired speed of rotation (S DK ) is determined from the values of the desired speed of rotation (S D ) and the weighted warp tension (K), and in that the speed of rotation of the warp beam ( 2 ) is controlled in dependence on the corrected desired speed of rotation (S DK ).

1 . Method for the regulation of the warp let-off of a weaving machine, in that a desired speed of rotation (S D ) is predetermined for a warp beam ( 2 ), in that a warp tension (K) of the warp threads ( 3 ) which are given off by the warp beam ( 2 ) is determined, in that the warp tension (K) is weighted with a weighting function (G) and in this manner a weighted warp tension (K G ) is determined, in that a corrected desired speed of rotation (S DK ) is determined from the values of the desired speed of rotation (S D ) and the weighted warp tension (K), and in that the speed of rotation of the warp beam ( 2 ) is controlled in dependence on the corrected desired speed of rotation (S DK ).  
     
     
         2 . Method in accordance with  claim 1 , characterized in that the added values of the desired speed of rotation (S D ) and the weighted warp tension (K G ) yield the corrected desired speed of rotation (S DK ).  
     
     
         3 . Method in accordance with any one of the preceding claims, characterized in that the weighting function (G) has only a factor α, by which the warp tension (K) is multiplied.  
     
     
         4 . Method in accordance with any one of the preceding claims, characterized in that the tension of the warp threads ( 3 ) is varied in that the value for the desired speed of rotation (S D ) and/or the value of the weighting function (G), in particular the value of the factor α, is varied.  
     
     
         5 . Method in accordance with any one of the preceding claims, characterized in that the weaving machine comprises a first and a second warp beam ( 2 ) which can be controlled separately; and in that for each warp beam ( 2 ) a separate, corrected desired speed of rotation (S DK ) is determined; and in that the speed of rotation of each warp beam ( 2 ) is controlled in accordance with the separate, corrected desired speed of rotation (S DK ).  
     
     
         6 . Method in accordance with  claim 5 , characterized in that the separate, corrected desired speed of rotation (S DK ) of the first warp beam ( 2 ) is used as the value for the desired speed of rotation (S D ) of the second warp beam ( 2 ).  
     
     
         7 . Method in accordance with any one of the preceding claims, characterized in that when the warp tension (K) exceeds or drops below a predetermined warp tension value (K SO , K SU ) the corrected desired speed of rotation (S DK ) is produced without using a value for the desired speed of rotation (S D ); in that a difference value is formed between the warp tension (K) and a predetermined desired warp tension (S K ) and the difference value which is weighted with the weighting function (G) forms the corrected desired speed of rotation (S DK ) by means of which the speed of rotation of the warp beam ( 2 ) is controlled.  
     
     
         8 . Method in accordance with any one of the preceding claims, characterized in that the warp thread length (L 1 ) which is given off from the warp beam ( 2 ) and the cloth length (L 2 ) which is produced are measured and the actual working in of the warp (C IST ) is determined therefrom.  
     
     
         9 . Method in accordance with  claim 8 , characterized in that the weighting function (G), in particular the factor α, is varied in dependence on the actual working in of the warp (C IST ).  
     
     
         10 . Apparatus for carrying out the method in accordance with any one of the preceding claims, comprising a tension sensor ( 5 ) for measuring the tension of the warp threads ( 3 ), comprising a speed of rotation sensor ( 7 ) for measuring the speed of rotation of the warp beam ( 2 ), comprising a regulation apparatus ( 1 ) which is connected in a signal-conducting manner to the tension sensor ( 5 ) and to the speed of rotation sensor ( 7 ), as well as comprising a motor ( 4 ) which drives the warp beam ( 2 ) and which is connected in a signal-conducting manner to the regulation apparatus ( 1 ).