Travelling service device for open-end spinning units of open-end spinning machines
Service trolley for open-end spinning machines having on-board members dedicated to the intervention cycles comprising a device for determining the position of the thread with respect to such members of the trolley that comprises a worm screw, with a horizontal axis parallel to the spinning machine, which engages the thread with its threading, said device being able to be lifted and actuated in commanded clockwise/anti-clockwise rotation to determine both the level of the thread and its axial coordinate.
1. Automatic service trolley for spinning units of open-end spinning machines for carrying out intervention cycles for starting, for reattachment of thread and lifting of completed cones of thread on individual spinning units, said trolley carrying on-board members or groups of members dedicated to single or multiple operations of the various cycles, as well as a device for controlling and positioning that determines the position, with respect to such members of the trolley, both of an auxiliary thread (A), which is adopted at a new quill ( 28 ) by the service trolley, and of the thread produced (F) that reaches a cone ( 25 ), characterized in that said device ( 31 ) for controlling the thread (A, F) consists of a worm screw ( 32 ), with a horizontal axis parallel to the front of the spinning machine, equipped with a cantilevered support arm ( 33 ) that allows it to be lowered or raised by rotation about a horizontal axis ( 34 ) parallel to the front of the spinning machine, the worm screw ( 32 ) being actuated into commanded clockwise/anticlockwise rotation by a motor ( 35 ), and the arm ( 33 ) also being actuated into rotation take up controlled angular positions that determine the level of the axis of the screw ( 32 ), and with it they determine the level at which the thread is carried, whereas the thread itself is engaged in the recess of the threading of the worm screw ( 32 ) and is transported in it by its rotation, which determines its axial coordinate, said automatic service trolley further characterized in that a deviator plate ( 36 ) in the form of a concave hut is fixed onto the support arm ( 33 ), with an apex ( 37 ) and a fold ( 38 ) that raises its external profile ( 39 ), said deviator plate being integral with the worm screw ( 32 ).
2. Automatic service trolley for spinning units of open-end spinning machines according to claim 1 , characterized in that the worm screw ( 32 ) has a diameter of between 15 and 30 mm and is equipped with rectangular threading with beveled edges with a pitch of 4–8 mm.
3. Automatic service trolley for spinning units of open-end spinning machines according to claim 1 , characterized in that the device ( 31 ) can go into three positions: rest (R), work (W) and tautness (T) according to the needs of the intervention cycles.
4. Automatic service trolley for spinning units of open-end spinning machines according to claim 3 , characterized in that the device ( 31 ) can go into a work position (W) situated at a level that keeps the thread protected from the excursions of the thread guide ( 21 ).
5. Automatic service trolley for spinning units of open-end spinning machines according to claim 1 , characterized in that the device ( 31 ) is equipped with actuation in rotation of the screw ( 32 ) with a brushless motor ( 35 ) driven in frequency by the trolley control unit to obtain angular positions and speeds that are controlled in the two directions of rotation.
6. Automatic service trolley for spinning units of open-end spinning machines according to claim 1 , characterized in that the device ( 31 ) is equipped with actuation in rotation of the screw ( 32 ) with a stepper motor ( 35 ) driven in steps by the trolley control unit, again to obtain angular positions and speeds that are controlled in the two directions of rotation.
7. Automatic service trolley for spinning units of open-end spinning machines according to claim 1 , characterized in that the device ( 31 ) is connected with a trolley control unit for the coordination of its operation with that of the other members on-board the trolley.
8. Automatic service trolley for spinning units of open-end spinning machines according to claim 1 , characterized in that the worm screw ( 32 ) of the device ( 31 ) has its end stop at the side of the arm ( 33 ) corresponding to the axial coordinate of the space between the base of a quill ( 28 ) and an open tailstock of said quill ( 27 ).