High-frequency thread-guide device for the production of bobbins with modulated traversing

Abstract

Thread-guide device with modulated traversing with an individual thread-guide having a back-and-forth movement fixed to a flexible element, moved between two pulleys in an alternating clockwise/anticlockwise movement, each driven by its own electric motor, both motors being piloted and coordinated to a control unit.

1 . A thread-guide device ( 18 ) for the collection of yarns on a bobbin ( 10 ), wherein the yarn (F) is distributed on the surface of the bobbin by a thread-guide ( 15 ) which moves with a back-and-forth movement parallel to the axis of the supporting roll ( 12 ) of the bobbin ( 10 ), and the thread-guide device ( 18 ) is driven with a back-and-forth movement by means of a flexible element ( 19 ), to which the thread-guide ( 15 ) is fixed, the flexible element ( 19 ) being moved between two pulleys ( 20   a ,  20   b ) which move with an alternating clockwise/anticlockwise movement by the activation of an electric motor piloted by a control unit, characterized in that the pulleys ( 20   a ,  20   b ) are activated by at least two electric motors ( 21   a ,  21   b ), the motors ( 21   a ,  21   b ) being controlled by at least one position detector and piloted by said control unit, which coordinates the piloting of said motors ( 21   a ,  21   b ) to produce the desired traversing movement. 
   
   
       2 . The thread-guide device for the collection of yarns on a bobbin according to  claim 1 , characterized in that said pulleys ( 20   a ,  20   b ) are driving pulleys each activated by at least one of its own electric motors ( 21   a ,  21   b ). 
   
   
       3 . The thread-guide device for the collection of yarns on a bobbin according to  claim 1 , characterized in that the motors ( 21   a ,  21   b ) are synchronous motors of the brushless or step-by-step type. 
   
   
       4 . The thread-guide device for the collection of yarns on a bobbin according to  claim 1 , characterized in that elastic elements for the accumulation of elastic energy, to be returned in the movement inversion points, are inserted between the fixed structure of each motor ( 21   a ,  21   b ) and the corresponding moving parts of the motor itself. 
   
   
       5 . The thread-guide device for the collection of yarns on a bobbin according to  claim 4 , characterized in that said elastic elements are torsion springs ( 25   a ,  25   b ), each of which is constrained with one of its ends ( 26   a ,  26   b ) to the driving shaft ( 28   a ,  28   b ) and with the other end ( 27   a ,  27   b ) to the fixed structure of the motor itself ( 21   a ,  21   b ). 
   
   
       6 . The thread-guide device for the collection of yarns on a bobbin according to  claim 1 , characterized in that the pulleys ( 20   a ,  20   b ) are toothed pulleys and the flexible element ( 19 ) consists of a closed toothed belt. 
   
   
       7 . The thread-guide device for the collection of yarns on a bobbin according to  claim 1 , characterized in that the flexible element ( 19 ) consists of a cord, which is wound onto two pulleys ( 20   a ,  20   b ), to which it is physically fixed with constraints ( 22 ). 
   
   
       8 . The thread-guide device for the collection of yarns on a bobbin according to  claim 7 , characterized in that the flexible element ( 19 ) consists of a cord which forms a closed circuit. 
   
   
       9 . The thread-guide device for the collection of yarns on a bobbin according to  claim 7 , characterized in that the flexible element ( 19 ) consists of a cord which forms an open circuit. 
   
   
       10 . The thread-guide device for the collection of yarns on a bobbin according to  claim 1 , characterized in that fixed repulsing elements ( 31   a ,  31   b ;  41   a ,  41   b ;  42   a ,  42   b ;  45   a ,  45   b ) are inserted in the device in correspondence with the ends of the traversing run of the thread-guide ( 15 ) to favour the movement inversion. 
   
   
       11 . The thread-guide device for the collection of yarns on a bobbin according to  claim 10 , characterized in that fixed repulsing elements are inserted in the device, consisting of permanent moveable magnets ( 30 ;  30   a ,  30   b ), which integrally follow the alternating movement of the thread-guide ( 15 ), and fixed magnetic bodies ( 31   a ,  31   b ,  41   a ,  41   b ;  42   a ,  42   b ), and said fixed and moveable magnetic bodies face each other in correspondence with the inversion points of the movements, having polarities of the same sign among each other. 
   
   
       12 . The thread-guide device for the collection of yarns on a bobbin according to  claim 11 , characterized in that the fixed magnetic bodies ( 31   a ,  31   b ,  41   a ,  41   b ) are permanent magnets. 
   
   
       13 . The thread-guide device for the collection of yarns on a bobbin according to  claim 11 , characterized in that the fixed magnetic bodies ( 42   a ,  42   b ) are bobbins. 
   
   
       14 . The thread-guide device for the collection of yarns on a bobbin according to  claim 11 , characterized in that the variation in the traversing run is effected by modifying the positions of the fixed magnetic bodies ( 31   a ,  31   b ;  41   a ,  41   b ;  42   a ,  42   b ). 
   
   
       15 . The thread-guide device for the collection of yarns on a bobbin according to  claim 14 , characterized in that the variation in the traversing run is effected by modifying the angular positions of the fixed magnetic bodies ( 31   a ,  31   b ;  41   a ,  41   b ), the permanent moveable magnets being constrained to the pulleys ( 20   a ,  20   b ). 
   
   
       16 . The thread-guide device for the collection of yarns on a bobbin according to  claim 15 , characterized in that the variation in the traversing run is effected by modifying the axial positions of the fixed magnetic bodies ( 31   a ,  31   b ;  42   a ,  42   b ), the permanent moveable magnet ( 30 ) being assembled on the body of the thread-guide ( 15 ) integrally following its alternating movement. 
   
   
       17 . The thread-guide device for the collection of yarns on a bobbin according to  claim 10 , characterized in that mechanical shock-absorber elements ( 45   a ,  45   b ) are inserted in the device in a position corresponding to the two ends of the traversing run of the thread-guide ( 15 ).