Clothing wire and method for producing staple fibre nonwovens

Abstract

A clothing wire for mounting on a clothing roll of a carding machine has a base section ( 1 ) and a blade section ( 4 ). A gradient dh/db of the height (h) as a function of the width (b) of at least a first section ( 10 ) of at least one blade-section side face ( 5, 6 ) is greater than the gradient dh/db of a second section ( 11 ) of the at least one blade-section side face ( 5, 6 ). The second section ( 11 ) is closer to the base section ( 1 ) than the first section ( 10 ). The sign of the gradients dh/db is the same. In a region which extends to a vertical distance of at most ⅛ of the overall height of the blade section beneath the at least one second portion ( 11 ), there no protrusions or indentations cause a gradient sign change on the at least one blade-section side face ( 5, 6 ).

1 . Sawtooth wire for mounting on a carding roll of a carding machine, the sawtooth wire comprising:
 a) a foot segment ( 1 ) with a base area ( 2 ) to be supported on a clothing roller, the base area ( 2 ) extending in a longitudinal direction (Z) and a lateral direction (B) of the sawtooth wire,   b) a blade segment ( 4 ) extending in a height direction (H), which is perpendicular to the base area ( 2 ), and having height values, as measured from the base area ( 2 ), increasing in a direction of a side of the blade segment ( 4 ) facing away from the foot segment ( 1 ) up to a maximum height (hmax) of the blade segment ( 4 ), and   c) the blade segment ( 4 ) being confined in the lateral direction (B) by a first ( 5 ) and a second ( 6 ) blade-segment lateral surface, wherein:   d) an absolute value of a gradient dh/db of height (h) as a function of breadth (b) at least of a first portion ( 10 ) at least of one of the first and the second blade-segment lateral surface ( 5 ,  6 ) is greater than a absolute value of a gradient dh/db of at least a second portion ( 11 ) of the at least of one of the first and the second blade-segment lateral surface ( 5 ,  6 ), wherein height values of the at least one second portion being smaller than height values of the at least one first portion ( 10 ) and the gradient dh/db of the at least one first portion ( 10 ) and of the at least one second ( 11 ) portion having a same sign,   e) gradients dh/db of portions on a same blade-segment lateral surface ( 5 ,  6 ) whose height values are in a range extending between a smallest height value (h 22 ) of the at least one second portion ( 11 ) and a further height value (h 3 ) which is located, at most, at ⅛ of an overall height (Hmax) of the blade segment ( 4 ) below the smallest height value (h 22 ) of the at least one second portion ( 11 ), have the same sign as the gradients dh/db of the at least one first portion ( 10 ) and of the at least one second ( 11 ) portion, and   f) a smallest height value (h 12 ) of the at least one first portion ( 10 ) being located in an area which is 50% to 98% of the overall height (Hmax) above a minimum height (hmin) of the blade segment ( 4 ).   
     
     
         2 . Sawtooth wire according to  claim 1 , wherein the gradients dh/db of the portions on the same blade-segment lateral surface ( 5 ,  6 ) whose height values are in the range extending between the smallest height value (h 22 ) of the at least one second portion ( 11 ) and the further height value (h 3 ) which is, at the most, ⅕ of the overall height (Hmax) of the blade segment below the smallest height value (h 22 ) of the at least one second portion ( 11 ), have the same sign as the gradients dh/db of the at least one first portion ( 10 ) and of the at least one second ( 11 ) portion. 
     
     
         3 . Sawtooth wire according to  claim 1 , wherein the gradients dh/db of the portions on the same blade-segment side ( 5 ,  6 ) whose height values are smaller than the smallest height value (h 22 ) of the at least one second portion ( 11 ) have the same sign as the gradients dh/db of the at least one first ( 10 ) and of the at least one second ( 11 ) portion. 
     
     
         4 . Sawtooth wire according to  claim 1 , wherein the smallest height value (h 12 ) of the at least one first portion ( 10 ) borders on a largest height value (h 21 ) of the at least one second portion ( 11 ). 
     
     
         5 . Sawtooth wire according to  claim 1 , comprising:
 an exterior surface ( 7 ), which limits the sawtooth wire in the height direction (H) on a side facing away from the foot segment ( 1 ) and which also extends in the height direction (H) and in so doing defines at least one tooth ( 8 ) of the sawtooth wire, and   wherein the at least one tooth ( 8 ) includes the at least one first portion ( 10 ) and the at least one second ( 11 ) portion.   
     
     
         6 . Sawtooth wire according to  claim 1 , wherein the at least one first portion ( 10 ) and the at least one second portion ( 11 ) are located at a point (z) in the sawtooth wire's longitudinal direction (Z). 
     
     
         7 . Sawtooth wire according to  claim 1 , wherein surface portions of the at least one blade-segment lateral surface ( 5 ,  6 ), which extend curvilinearly in a plane defined by the lateral direction (B) and the height direction (H). 
     
     
         8 . Sawtooth wire according to  claim 1 , comprising a first straight surface portion ( 33 ) and a second ( 34 ) straight surface portion of the at least one blade-segment lateral surface ( 5 ,  6 ), which extend straight in a plane defined by the lateral direction (B) and the height direction (H), which follow each other in succession in the height direction (H), and which define an angle (α 3 ) in the plane defined by the lateral direction (B) and the height direction (H). 
     
     
         9 . Sawtooth wire according to  claim 1 , wherein at most four straight surface portions follow each other in succession in the height direction (H). 
     
     
         10 . Sawtooth wire according to  claim 1 , wherein a highest straight surface portion ( 33 ) and a surface portion ( 34 ) adjacent thereto border on each other in a height region located between 5/10 and 9/10 of the overall height (Hmax) above the minimum height (hmin) of the blade segment ( 4 ). 
     
     
         11 . Sawtooth wire according to  claim 1 , comprising at least a first portion ( 10 ) of the at least one blade-segment lateral surface ( 5 ,  6 ), said first portion making an angle of less than 5° with a line perpendicular ( 19 ) dropped to the base area ( 2 ) of the foot. 
     
     
         12 . Sawtooth wire according to  claim 11 , wherein the at least a first portion ( 10 ) of the at least one blade-segment lateral surface ( 5 ,  6 ) runs parallel to the line perpendicular ( 19 ) to the base area of the foot. 
     
     
         13 . Sawtooth wire according to  claim 1 , comprising at least one first portion ( 10 ) of the first blade-segment lateral surface ( 5 ), said first portion running parallel to a portion, located at a same height, of the second blade-segment lateral surface ( 6 ). 
     
     
         14 . Sawtooth wire according to  claim 11 , comprising at least a second portion ( 11 ) of the at least one blade-segment lateral surface ( 5 ,  6 ), said second portion making an angle (α 2 ), which is greater than 6°, with the line perpendicular ( 19 ) to the base area of the foot. 
     
     
         15 . Method of manufacturing fibre fleeces, the method comprising:
 processing cotton and/or synthetic fibres using a sawtooth wire comprising:   a) a foot segment ( 1 ) with a base area ( 2 ) to be supported on a clothing roller, the base area ( 2 ) extending in a longitudinal direction (Z) and a lateral direction (B) of the sawtooth wire,   b) a blade segment ( 4 ) extending in a height direction (H), which is perpendicular to the base area ( 2 ), and having height values, as measured from the base area ( 2 ), increasing in a direction of a side of the blade segment ( 4 ) facing away from the foot segment ( 1 ) up to a maximum height (hmax) of the blade segment ( 4 ), and   c) the blade segment ( 4 ) being confined in the lateral direction (B) by a first ( 5 ) and a second ( 6 ) blade-segment lateral surface, wherein:   d) an absolute value of a gradient dh/db of height (h) as a function of breadth (b) at least of a first portion ( 10 ) at least of one of the first and the second blade-segment lateral surface ( 5 ,  6 ) is greater than a absolute value of a gradient dh/db of at least a second portion ( 11 ) of the at least of one of the first and the second blade-segment lateral surface ( 5 ,  6 ), wherein height values of the at least one second portion being smaller than height values of the at least one first portion ( 10 ) and the gradient dh/db of the at least one first portion ( 10 ) and of the at least one second ( 11 ) portion having a same sign,   e) gradients dh/db of portions on a same blade-segment lateral surface ( 5 ,  6 ) whose height values are in a range extending between a smallest height value (h 22 ) of the at least one second portion ( 11 ) and a further height value (h 3 ) which is located, at most, at ⅛ of an overall height (Hmax) of the blade segment ( 4 ) below the smallest height value (h 22 ) of the at least one second portion ( 11 ), have the same sign as the gradients dh/db of the at least one first portion ( 10 ) and of the at least one second ( 11 ) portion, and   f) a smallest height value (h 12 ) of the at least one first portion ( 11 ) being located in an area which is 50% to 98% of the overall height (Hmax) above a minimum height (hmin) of the blade segment ( 4 ).   
     
     
         16 . Method according to  claim 15 , wherein the processing the cotton and/or synthetic fibres using the sawtooth wire comprises processing the cotton and/or synthetic fibres using a sawtooth wire having the overall height (Hmax) of less than 4.0 mm. 
     
     
         17 . Method according to  claim 15 , wherein the processing the cotton and/or synthetic fibres using the sawtooth wire comprises processing the cotton and/or synthetic fibres using a sawtooth wire having a highest straight surface portion ( 33 ) and a second surface portion ( 34 ) bordering the highest straight surface portion ( 33 ) in a height region which, in the height direction (H), is located between 5/100 and 2/10 mm below the maximum height (hmax).