Spinning unit and air jet spinning machine having such a spinning unit

Abstract

An air jet spinning machine, air jet spinning machine for producing a thread from a fed sliver, and method for detecting a thread strength, which falls below a target value, of a thread produced at a spinning unit of an airjet spinning machine are provided. A thread manipulation unit is arranged in the region between the airjet spinning machine and the spooling device, which thread manipulation unit acts mechanically on the thread and exerts an adjustable thread tension influencing force, in particular an adjustable braking force, compression force and/or clamping force, onto the thread in order to variably increase thread tension. In the method, an adjustable thread tension influencing force is exerted onto the thread, and a thread breakage and/or thread breakage rate are/is detected and compared with a specified target rate, and thread breakage and/or deviations of thread breakage rate beyond a predetermined limit value are displayed and/or evaluated.

1 . A spinning unit for an air jet spinning machine for manufacturing a thread from a supplied fibre band, comprising
 an air-jet spinning device for forming a thread from at least one fibre band fed via a drafting system, and   a winding device for taking up the thread on a take-up package,   characterised in that,   in the area between the air-jet spinning device and the winding device, a thread manipulation unit is arranged, which acts mechanically on the thread and exerts an adjustable thread-tension-influencing force on the thread to variably increase the thread tension.   
     
     
         2 . The spinning unit according to  claim 1 , characterised in that the thread manipulation unit has an adjustable clamp toward the thread. 
     
     
         3 . The spinning unit according to  claim 2 , characterised in that the clamp is formed by a disc tensioner and/or gate tensioner for adjustable drawing of the thread. 
     
     
         4 . The spinning unit according to  claim 1 , characterised in that the thread manipulation unit has an adjustable deflector. 
     
     
         5 . The spinning unit according to  claim 1 , characterised in that the adjustable thread-tension-influencing force is electrically adjustable. 
     
     
         6 . The spinning unit according to  claim 1 , characterised by a sensor for measuring the thread tension of the thread section that can be or is influenced by the thread manipulation unit. 
     
     
         7 . The spinning unit according to  claim 1 , characterised in that the thread manipulation unit is arranged in the area between the air-jet spinning device and a thread take-up unit. 
     
     
         8 . Air jet spinning machine for manufacturing a thread from a supplied fibre band, characterised by at least one spinning unit according to  claim 1 . 
     
     
         9 . Air jet spinning machine according to  claim 8 , characterised by an associated evaluating unit for detecting a thread break and/or thread break rate at the spinning units and comparing the thread break rate with target rates that can be specified. 
     
     
         10 . Air jet spinning machine according to  claim 8 , characterised by an associated controlling unit for detecting the thread tensile force by thread tensile-force sensors arranged at the spinning units and for adjusting the thread-tension-influencing force of the thread manipulation unit. 
     
     
         11 . A method for detecting a thread strength of a thread manufactured at a spinning unit of an air jet spinning machine which falls below a target value, wherein
 an adjustable thread-tension-influencing force is applied to the thread by a thread manipulation unit, which is arranged in the area between an air-jet spinning device and a winding device and acts mechanically on the thread, and   a thread break and/or thread break rate is detected and compared with a specified target rate, and the thread break and/or deviations of the thread break rate beyond a predefined limit value are indicated and/or evaluated.   
     
     
         12 . The spinning unit according to  claim 1 , characterized in that the adjustable thread-tension-influencing force is an adjustable braking, compressive and/or clamping force. 
     
     
         13 . The spinning unit according to  claim 4 , characterized in that the adjustable deflector is an adjustable eyelet for variably altering the thread path.