Method and Apparatus for Producing Staple Fibers

Abstract

A method and an apparatus for producing staple fibers, wherein in a first step a tow is formed from melt spun filaments and deposited into a can, and wherein in a second process step the tows of a plurality of cans in a can creel are withdrawn, treated, and cut to staple fibers. To obtain as much as possible short times of interruption between the first and second process steps, the invention provides for depositing the tow in the first process step directly into the can accommodated in the can creel, with the cans of the can creel being filled one after the other.

1 . A method of producing staple fibers, comprising the steps of 
 forming a tow of melt spun filaments,    successively depositing the tow into each of a plurality of cans accommodated in a can creel, and    withdrawing the tow from the cans of the can creel and treating and cutting the withdrawn tow.    
   
   
       2 . The method of  claim 1 , wherein the withdrawing step is conducted after the tow has been deposited into all of the cans of the can creel and while the tow is successively deposited into each of the cans accommodated in a second can creel.  
   
   
       3 . A method of producing staple fibers, comprising the steps of 
 forming a tow of melt spun filament strands,    alternately (1) successively depositing the tow into each of a plurality of cans accommodated in a first can creel, and (2) successively depositing the tow into each of a plurality of cans accommodated in a second can creel, and    withdrawing the tow from the cans of the second can creel while the tow is deposited in the cans of the first can creel, and withdrawing the tow from the cans of the first can creel while the tow is deposited in the cans of the second can creel.    
   
   
       4 . The method of  claim 3 , wherein the tow is deposited by a movable depositing device into each can that is to be filled, with the depositing device being supported above the associated can creel.  
   
   
       5 . The method of  claim 4 , wherein during the depositing step, an oscillating movement is imparted to the tow by the depositing device.  
   
   
       6 . The method of  claim 5 , wherein the oscillating movement of the tow is generated by a movably mounted conveying means.  
   
   
       7 . The method of  claim 3 , wherein during each of the depositing steps, the can receiving the tow performs an oscillating movement in the can creel.  
   
   
       8 . An apparatus for producing staple fibers, comprising 
 a melt spinning unit for melt spinning a plurality of filaments and gathering the filaments to form a tow,    a depositing device for successively depositing the tow into each of a plurality of cans which are accommodated in a can creel, and    a treatment unit for withdrawing the tow from the cans of the can creel and treating and cutting the withdrawn tow.    
   
   
       9 . The apparatus of  claim 8 , further comprising a second can creel arranged adjacent the first mentioned can creel, and wherein both can creels are arranged relative to the melt spinning unit such that the cans of the two can creels can be alternately filled with the tow.  
   
   
       10 . The apparatus of  claim 9 , wherein the two can creels are arranged relative to the treatment unit such that the tows of the cans of the two can creels can be alternately withdrawn.  
   
   
       11 . The apparatus of  claim 10 , wherein the melt spinning unit comprises a movable depositing device which is supported and moved by a guide system which is supported above the can creels.  
   
   
       12 . The apparatus of  claim 11 , further comprising a moving means which causes the depositing device to perform an oscillating movement while depositing the tow.  
   
   
       13 . The apparatus of  claim 12 , wherein the moving means is associated with a conveying means which is adapted for advancing the tow into the respectively associated can.  
   
   
       14 . The apparatus of  claim 10 , further comprising a can traversing mechanism for imparting oscillating movement to the cans of each of the can creels while the tow is deposited thereinto.  
   
   
       15 . The apparatus of  claim 8 , wherein the melt spinning unit comprises a plurality of spinnerets for extruding a plurality of filaments and a withdrawal system for withdrawing and gathering the filaments from the spinnerets to form a tow which is advanced to the depositing device.  
   
   
       16 . The apparatus of  claim 15 , further comprising a feed system for advancing the tow from the withdrawal system to the depositing device.  
   
   
       17 . The apparatus of  claim 16 , wherein the spinnerets and the withdrawal system of the melt spinning unit are arranged upstream of the can creels, with the spinnerets being mounted in centered relationship with the can creels or in offset relationship with the can creels.  
   
   
       18 . The apparatus of  claim 10 , further comprising a withdrawal guide element associated with each can of the can creels and with each withdrawal guide element being adapted for movement between an idle position and an operating position where it serves to facilitate the withdrawal of the tow from the cans.