Device to improve the yarn threading of the thread guides for warp linear knitting machines

1. A device ( 1 ) for improving the threading of thread-guides ( 5 ) for warp linear knitting machines ( 10 ), comprising:

at least a first support ( 6 ) that is coupled to a supporting structure ( 11 ) of a warp linear knitting machine ( 10 ),

a plurality of thread-guides ( 5 ) designed to guide threads while knitting a knitted item, and a plurality of thread-guide ( 5 ) bars ( 2 ) operatively coupled to said first support ( 6 ), said plurality of thread-guides ( 5 ) being coupled to said plurality of thread-guide ( 5 ) bars ( 2 );

said first support ( 6 ) being movable with respect to said supporting structure ( 11 ) between an operating position, in which said thread-guides ( 5 ) are active for the formation of said knitting item, and at least one threading position, angularly rotated with respect to said operating position, in which the thread-guides ( 5 ) are led outside the knitting area and the threading of said thread-guides ( 5 ) takes place.

2. The device ( 1 ) according to claim 1 , characterized in that said first support ( 6 ) is movable between said operating position and two of said threading positions, a first one of said two threading positions being rotated with respect to said operating position clockwise and a second one of said two threading positions being rotated counterclockwise.

3. The device ( 1 ) according to claim 1 , characterized in that it further comprises an oscillating shaft ( 12 ) having a main axis ( 13 ), said first support ( 6 ) being movable between said operating position and said at least one threading position by rotating around said main axis ( 13 ) of said oscillating shaft ( 12 ).

4. The device ( 1 ) according to claim 3 , characterized in that it further comprises a second support ( 7 ) operatively placed between said supporting structure ( 11 ) and said first support ( 6 ) and moving between said operating position and said at least one threading position integrally with said first support ( 6 ).

5. The device ( 1 ) according to claim 4 , characterized in that in said operating position said first support ( 6 ) is movable with respect to said second support ( 7 ) with oscillating motion around said main axis ( 13 ) of said oscillating shaft ( 12 ) so as to move said thread-guides ( 5 ) by means of said thread-guide ( 5 ) bars ( 2 ) transversally with respect to the hook of needles ( 16 ) for feeding correctly the threads onto said needles ( 16 ).

6. The device according to claim 5 , characterized in that said oscillating motion of said first support ( 6 ) with respect to said second support ( 7 ) around said main axis ( 13 ) of said oscillating shaft ( 12 ) is less broad than the movement of said first ( 6 ) and said second ( 7 ) support with respect to said supporting structure ( 11 ) around said main axis ( 13 ) of said oscillating shaft ( 12 ) for the passage between the operating position and the threading positions.

7. The device ( 1 ) according to claim 4 , characterized in that it further comprises a blocker ( 20 ) designed to block said first ( 6 ) and said second ( 7 ) support in rotation with respect to said supporting structure ( 11 ) so as to let them stay in operating position, and to release said first ( 6 ) and said second ( 7 ) support in rotation with respect to said supporting structure ( 11 ) so as to enable the movement thereof from said operating position to said at least one threading position.

8. The device according to claim 7 , characterized in that said blocker ( 20 ) comprises a bolt ( 21 ) that is movable with respect to said supporting structure ( 11 ) according to a basically vertical direction perpendicular to the main axis ( 13 ) of said oscillating shaft ( 12 ) between a lowered position and a lifted position, and an engagement element ( 22 ) operatively coupled to said bolt ( 21 ) so as to move longitudinally between an active position, when said bolt ( 21 ) is in said lowered position, in which said engagement element ( 22 ) acts operatively upon said second support ( 7 ) so as to block it in rotation with respect to the supporting structure ( 11 ), and a passive position, when said bolt ( 21 ) is in lifted position, in which said engagement element ( 22 ) is led away from said second support ( 7 ) so as to enable the rotation thereof for the passage from the operating position to the threading positions.

9. The device according to claim 8 , characterized in that said engagement element ( 22 ) comprises a rod ( 23 ) developing according to a longitudinal direction basically perpendicular to the direction of movement of the bolt ( 21 ), and a bracket ( 26 ) fitted onto a first end ( 24 ) of said rod ( 23 ), designed, when said engagement element ( 22 ) is in active position, to exert a pushing action onto said second support ( 7 ) that is basically perpendicular to said second support ( 7 ), so as to prevent the rotation thereof with respect to the supporting structure ( 11 ).

10. The device according to claim 9 , characterized in that said bolt ( 21 ) has a cam profile ( 27 ), said rod ( 23 ) being operatively coupled to said cam profile ( 27 ) on a second end ( 25 ) thereof, and in that said blocker ( 20 ) further comprises a pushing element ( 31 ) acting upon said second end ( 25 ) of said rod ( 23 ) so as to push it against said cam profile ( 27 ) so as to move said rod ( 23 ) and said bracket ( 26 ) between the passive and the active position.

11. The device according to claim 10 , characterized in that said blocker ( 20 ) comprises a first bearing ( 32 ) moving longitudinally according to the direction of movement of the rod ( 23 ) and firmly fitted onto said rod ( 23 ) on said second end ( 25 ), said pushing element ( 31 ) acting upon said rod ( 23 ) by means of said first bearing ( 32 ) and said rod ( 23 ) being operatively coupled to said cam profile ( 27 ) by means of said first bearing ( 32 ).

12. The device ( 1 ) according to claim 11 , characterized in that said cam profile ( 27 ) is tapered down at least on one side, having at least a first portion ( 28 ) and a second portion ( 29 ), which is longitudinally concave with respect to said first portion ( 28 ), and in that, when said bolt ( 21 ) is in said lowered position, said first bearing ( 32 ) is in contact with said first portion ( 28 ) of said cam profile ( 27 ) so that the rod ( 23 ) in active position is pulled back longitudinally for blocking the rotation of said second support ( 7 ) with respect to the supporting structure ( 11 ), and when said bolt ( 21 ) is in said lifted position, said first bearing ( 32 ) is in contact with said second portion ( 29 ) of said cam profile ( 27 ) so that the rod ( 23 ) in passive position is pushed forward longitudinally for releasing the second support ( 7 ) from rotation with respect to the supporting structure ( 11 ).

13. The device ( 1 ) according to claim 8 , characterized in that said blocker ( 20 ) further comprises an activation element ( 33 ) designed to move said bolt ( 21 ) between said lifted and said lowered position.

14. The device ( 1 ) according to claim 8 , characterized in that said blocker ( 20 ) further comprises at least one second bearing ( 34 ) designed to guide said bolt ( 21 ) in its movement from said lifted and said lowered position and to cooperate with said pushing element ( 31 ) and with said first bearing ( 32 ) for stiffly keeping said rod ( 23 ) and said bracket ( 26 ) in active position.

15. The device ( 1 ) according to claim 8 , characterized in that said bolt ( 21 ) in said lowered position engages with said second support ( 7 ) on an upper portion ( 7 a ) thereof.

16. The device ( 1 ) according to claim 15 , characterized in that said blocker ( 20 ) further comprises a first guide ( 37 a ) coupled to said upper portion ( 7 a ) of said second support ( 7 ), and a second guide ( 37 b ) coupled to the supporting structure ( 11 ) of the machine ( 10 ) on the bolt ( 21 ), said first ( 37 a ) and said second ( 37 b ) guides being designed to improve the sliding of the bolt ( 21 ) and to stiffly fit the bolt ( 21 ) onto the second support ( 7 ).

17. The device ( 1 ) according to claim 1 , characterized in that it further comprises a mover ( 40 ) operatively coupled to said first ( 6 ) or to said second ( 7 ) support and designed to move said first ( 6 ) and said second ( 7 ) support between said operating position and said at least one threading position.

18. The device ( 1 ) according to claim 17 , characterized in that said mover ( 40 ) comprises an actuating element ( 41 ) coupled to said second support ( 7 ) and designed to impart to said first ( 6 ) and said second ( 7 ) support a pushing and for pulling action for moving them between said operating position and said at least on threading position.

19. The device ( 1 ) according to claim 18 , characterized in that said actuating element ( 41 ) has a basically vertical development perpendicular to the main axis ( 13 ) of the oscillating shaft ( 12 ) and it is coupled by means of a lower end ( 42 ) thereof to a lateral portion ( 8 ) of said second support ( 7 ), at least said lower end ( 42 ) of said actuating element ( 41 ) being movable and articulated, when said bolt ( 21 ) is in lifted position, according to a vertical direction pointing downwards between a rest position in which the first support ( 6 ) is in operating position, and a pushing position for pushing said first ( 6 ) and said second ( 7 ) support between said operating position and a first threading position or between a second threading position and said operating position, and according to a vertical direction pointing upwards between said rest position and a pulling position for pulling said first ( 6 ) and said second ( 7 ) support between said operating position and said second threading position or between said first threading position and said operating position.

20. The device ( 1 ) according to claim 18 , characterized in that said mover ( 40 ) comprises a pneumatic piston ( 43 ), said actuating element ( 41 ) being a stem of said pneumatic piston ( 43 ).

21. The device ( 1 ) according to claim 18 , characterized in that said mover ( 40 ) comprises a screw motor, said actuating element ( 41 ) being a screw of said motor.

22. The device ( 1 ) according to claim 4 , characterized in that said supporting structure ( 11 ) comprises a guide ( 14 ) having a basically curved shape, and in that said second support ( 7 ) comprises at least one third bearing ( 15 ) designed to slide in said guide ( 14 ) for guiding the movement of said second support ( 7 ) between said operating position and said at least one threading position.

23. A warp linear knitting machine ( 10 ) characterized in that it comprises at least one of said devices ( 1 ) for threading thread-guides ( 5 ) according to claim 1 .

24. The machine ( 10 ) according to claim 23 , characterized in that it comprises at least two of said devices ( 1 ), one of said devices ( 1 ) being positioned on a first end portion ( 3 ) of said plurality of thread-guide ( 5 ) bars ( 2 ), and one being positioned on a second end portion ( 4 ), opposite said first end portion ( 3 ), so as to prevent torsions of said plurality of thread-guide ( 5 ) bars ( 2 ).

25. The machine ( 10 ) according to claim 24 , characterized in that it comprises an adjuster and controller designed to control the function thereof.

26. The machine ( 10 ) according to claim 25 , characterized in that said activation element ( 33 ) is selectively activated by said adjuster and controller.

27. The machine ( 10 ) according to claim 25 , characterized in that said mover ( 40 ) is selectively activated by said adjuster and controller.