Crimper and method for producing tow band

Abstract

A crimper (1) includes: a pair of nip rolls (2) including respective peripheral surfaces between which conveyed filaments (11) pass; a first member (6) and a second member (7) including contact surfaces (6a, 7a) that come into contact with the filaments and being disposed on a downstream side of the pair of nip rolls in a conveyance direction of the filaments, the respective contact surfaces being disposed facing each other across a gap; and a pressing member (5) disposed in the gap and configured to press the filaments toward the contact surface of any of the first member and the second member. A surface roughness Ra of the contact surfaces is set to a value in a range of from 0.1 to 1.0.

1 - 16 . (canceled) 
     
     
         17 . A crimper comprising:
 a pair of nip rolls including respective peripheral surfaces between which conveyed filaments pass;   a first member and a second member including respective contact surfaces that come into contact with the filaments and being disposed on a downstream side of the pair of nip rolls in a conveyance direction of the filaments, the contact surfaces being disposed facing each other across a gap; and   a pressing member disposed in the gap and configured to press the filaments toward the contact surface of any of the first member and the second member, wherein   a surface roughness Ra of the contact surfaces is set to a value in a range of from 0.1 to 1.0.   
     
     
         18 . The crimper according to  claim 17 , wherein a Rockwell hardness HRC of the first member and the second member is set to a value in a range of from 50 to 60. 
     
     
         19 . The crimper according to  claim 17 , wherein a Vickers hardness HV of the first member and the second member is set to a value of 350. 
     
     
         20 . The crimper according to  claim 17 , wherein at least one of the first member or the second member includes a substrate having a flat plate shape and a coating film that covers a surface of the substrate and is harder than the substrate, the coating film including the contact surface that is positioned on an opposite side of the coating film from the substrate. 
     
     
         21 . The crimper according to  claim 20 , wherein the coating film is a chromium nitride film. 
     
     
         22 . The crimper according to  claim 17 , wherein a coefficient of kinetic friction between the contact surfaces and the filaments is set to a value in a range of from 0.1 to 0.5. 
     
     
         23 . The crimper according to  claim 17 , wherein a velocity CV, represented by Equation 1, of the filaments conveyed in the gap is set to a value between 0% and 100%:
   velocity  CV (%)=(σ/ Vm )×100,  [Equation 1]
   where Vm is an average velocity value that is an average of measured values of a velocity of the filaments immediately before the velocity of the filaments is shifted from acceleration to deceleration within a unit time and of a velocity of the filaments immediately before the velocity is shifted from deceleration to acceleration within the unit time, and σ is a standard deviation of the measured values.   
     
     
         24 . The crimper according to  claim 17 , wherein a content of titanium oxide in the filaments is set to a value in a range of from 0 wt. % to 0.1 wt. %. 
     
     
         25 . A method for producing a tow band, the method comprising a step, the step including:
 causing conveyed filaments to pass between respective peripheral surfaces of a pair of nip rolls;   introducing the filaments having passed between the pair of nip rolls into a gap between a first member and a second member disposed on a downstream side of the pair of nip rolls in a conveyance direction of the filaments and having respective contact surfaces disposed facing each other across the gap; and   pressing the filaments toward the contact surface of any of the first member and the second member using a pressing member disposed in the gap, wherein   in the step, the first member and the second member having a surface roughness Ra of the contact surfaces set to a value in a range of from 0.1 to 1.0 are used.   
     
     
         26 . The method for producing a tow band according to  claim 25 , wherein, in the step, the first member and the second member having a Rockwell hardness HRC set to a value in a range of from 50 to 60 are used. 
     
     
         27 . The method for producing a tow band according to  claim 25 , wherein, in the step, the first member and the second member having a Vickers hardness HV set to a value of 350 or greater are used. 
     
     
         28 . The method for producing a tow band according to  claim 25 , wherein, in the step, at least one of the first member or the second member including a substrate having a flat plate shape and a coating film that covers a surface of the substrate and is harder than the substrate is used, and the coating film including the contact surface that is positioned on-an opposite side of the coating film from the substrate. 
     
     
         29 . The method for producing a tow band according to  claim 28 , wherein, in the step, the first member and the second member in which the coating films are chromium nitride films are used. 
     
     
         30 . The method for producing a tow band according to  claim 25 , wherein, in the step, the first member and the second member having a coefficient of kinetic friction between the contact surfaces and the filaments set to a value in a range of from 0.1 to 0.5 are used. 
     
     
         31 . The method for producing a tow band according to  claim 25 , wherein, in the step, a velocity CV, represented by Equation 1, of the filaments conveyed in the gap is set to a value between 0% and 100%:
   velocity  CV (%)=(σ/ Vm )×100,  [Equation 1]
   where Vm is an average velocity value that is an average of measured values of a velocity of the filaments immediately before the velocity of the filaments is shifted from acceleration to deceleration within a unit time and of a velocity of the filaments immediately before the velocity is shifted from deceleration to acceleration within the unit time, and σ is a standard deviation of the measured values.   
     
     
         32 . The method for producing a tow band according to  claim 25 , wherein, in the step, the filaments having a content of titanium oxide set to a value from 0 wt. % to 0.1 wt. % are used.