An open-end spinning machine having a plurality of workstations, each workstation has a spinning apparatus for producing a thread, a thread draw-off device for drawing off the thread from the spinning apparatus, a storage nozzle, a winding apparatus for producing a cross-wound bobbin, and a suction nozzle, to which negative pressure can be applied. The open-end spinning machine is equipped with at least one service unit, serving a plurality of the workstations and has an auxiliary-thread delivery device for delivering an auxiliary thread and an auxiliary-thread draw-off, which are used in a piecing process at a workstation to be served. The auxiliary-thread draw-off can be operated in such a way that the auxiliary-thread draw-off speed of the auxiliary-thread draw-off for drawing off the pieced auxiliary thread has a speed offset, which takes into account the thread draw-off speed of the thread draw-off device and at least one additional correction factor.

An open-end spinning machine having a plurality of workstations, each workstation has a spinning apparatus for producing a thread, a thread draw-off device for drawing off the thread from the spinning apparatus, a storage nozzle, a winding apparatus for producing a cross-wound bobbin, and a suction nozzle, to which negative pressure can be applied. The open-end spinning machine is equipped with at least one service unit, serving a plurality of the workstations and has an auxiliary-thread delivery device for delivering an auxiliary thread and an auxiliary-thread draw-off, which are used in a piecing process at a workstation to be served. The auxiliary-thread draw-off can be operated in such a way that the auxiliary-thread draw-off speed of the auxiliary-thread draw-off for drawing off the pieced auxiliary thread has a speed offset, which takes into account the thread draw-off speed of the thread draw-off device and at least one additional correction factor.

A method is provided for identifying a spinning rotor on a rotor spinning machine, wherein the spinning rotor is mounted in a suspended manner in a radially acting magnetic bearing during a spinning operation. At least one system variable that varies between different spinning rotors is identified. The system variable is detected and compared to at least one reference value. The system variable is one or a combination of: an energy consumption of the magnetic bearing; a radial position of the spinning rotor; or a resonant frequency of the spinning rotor. A rotor spinning machine that carries out the method is also provided.

A rotor spinning machine has a multiple number of work stations arranged side by side in the longitudinal direction of the rotor spinning machine between two front-side ends of the rotor spinning machine, each of which work stations has a multiple number of work elements for the production and winding of a yarn. The work elements comprise at least one feed device, one severing device, one spinning rotor along with one winding device. Furthermore, the rotor spinning machine has a suction device for producing a negative spinning pressure at the work stations. The suction device includes at least two separate negative pressure sources, whereas one negative pressure source is arranged on each of the two front-side ends of the rotor spinning machine, and whereas each of the negative pressure sources is connected to a separate negative pressure channel that extends in the longitudinal direction of the rotor spinning machine only over a part of the work stations, It is provided that the suction device includes at least two separate negative pressure sources, whereas at least one negative pressure source is arranged on each of the two front-side ends of the rotor spinning machine, and whereas each of the two negative pressure sources is connected to a separate negative pressure channel that extends in the longitudinal direction of the rotor spinning machine only over a part of the work stations. Thereby, each work station has an individual drive, in particular a single electric drive, for the spinning rotor.

The present invention relates to a method for handling a yarn end (10) of a cross-wound bobbin (2) at a winding station (1) of a textile machine producing a cross-wound bobbin, whereas the cross-wound bobbin can be held and driven in a bobbin holder (3), a thread (6) is laid in a cross-wise manner on the cross-wound bobbin by means of a traverse device (5) and a suction nozzle (7; 12) is subjected to negative pressure and the thread end is sucked into the suction nozzle through a suction mouth (8; 13). In accordance with the invention, it is proposed that the suction mouth is moved relative to the suction nozzle, such that the distance between the suction mouth and the cross-wound bobbin is changed, in order to be able to find the thread end and/or to be stretched between the suction mouth and the cross-wound bobbin and that the stretched thread is moved to a unit (9) of the textile machine for further processing. Furthermore, the invention relates to a winding station of a textile machine producing cross-wound bobbins (2) with a bobbin holder (3), a traversing device (5) and a suction nozzle (7; 12) that can be subjected to negative pressure with a suction mouth (8; 13) arranged in a movable manner on the suction nozzle, in order to be able to find the thread end (10) and/or to stretch it between the suction mouth and the cross-wound bobbin, and with a thread handling element (8; 13; 16; 18), in order to be able to move the stretched thread (6) to a unit (9) of the textile machine for further processing.

The present invention relates to a method for handling a yarn end (10) of a cross-wound bobbin (2) at a winding station (1) of a textile machine producing a cross-wound bobbin, whereas the cross-wound bobbin can be held and driven in a bobbin holder (3), a thread (6) is laid in a cross-wise manner on the cross-wound bobbin by means of a traverse device (5) and a suction nozzle (7; 12) is subjected to negative pressure and the thread end is sucked into the suction nozzle through a suction mouth (8; 13). In accordance with the invention, it is proposed that the suction mouth is moved relative to the suction nozzle, such that the distance between the suction mouth and the cross-wound bobbin is changed, in order to be able to find the thread end and/or to be stretched between the suction mouth and the cross-wound bobbin and that the stretched thread is moved to a unit (9) of the textile machine for further processing. Furthermore, the invention relates to a winding station of a textile machine producing cross-wound bobbins (2) with a bobbin holder (3), a traversing device (5) and a suction nozzle (7; 12) that can be subjected to negative pressure with a suction mouth (8; 13) arranged in a movable manner on the suction nozzle, in order to be able to find the thread end (10) and/or to stretch it between the suction mouth and the cross-wound bobbin, and with a thread handling element (8; 13; 16; 18), in order to be able to move the stretched thread (6) to a unit (9) of the textile machine for further processing.

An open-end spinning device for an open-end spinning machine includes a rotor housing and a spinning rotor having a rotor cup accommodated in the rotor housing. A drive for the spinning rotor is arranged in a drive housing. At least one receptacle for a cover element that closes the rotor housing during spinning operations is provided. The rotor housing includes an adjustable stop for the cover element, the stop positioning the cover element in an axial direction of the spinning rotor.

A textile machine for producing cross-wound packages, comprising a plurality of workstations, each of which has at least one pneumatic consumer, and comprising a suction system which has at least one vacuum source to which the pneumatic consumers of the workstations are connected via a machine-length vacuum duct arranged in the region of the central axis between two rows of workstations. In order to modify such a textile machine producing cross-wound packages in such a way that it is ensured that the required minimum spinning vacuum is always available at all workstations of the textile machine during spinning operation, according to the invention the textile machine producing cross-wound packages has, in addition to the vacuum duct, a machine-length bypass duct which is also installed in the region of the central axis and is arranged above chain ducts for service units.

An open-end spinning device having a rotor housing (1) which can be acted upon by negative pressure and a spinning rotor (2), the rotor housing (1) is open towards the front and can be closed by a cover element, to the rear the rotor housing (1) has a rear wall (3) with a passage opening (4) for a rotor shaft (5) of the spinning rotor (2). In order to prevent the occurrence of thread coils inside the rotor housing (1) behind the spinning rotor, a narrow gap (6) of less than 2 mm is provided between the spinning rotor (2) and the rear wall (3) of the rotor housing (1) at the largest outer diameter of the spinning rotor (2) and the rear wall (3) of the rotor housing (1) is designed such that the area (7) behind the spinning rotor (2) is covered inside the rotor housing (1).

An open-end spinning device having a rotor housing (1) which can be acted upon by negative pressure and a spinning rotor (2), the rotor housing (1) is open towards the front and can be closed by a cover element, to the rear the rotor housing (1) has a rear wall (3) with a passage opening (4) for a rotor shaft (5) of the spinning rotor (2). In order to prevent the occurrence of thread coils inside the rotor housing (1) behind the spinning rotor, a narrow gap (6) of less than 2 mm is provided between the spinning rotor (2) and the rear wall (3) of the rotor housing (1) at the largest outer diameter of the spinning rotor (2) and the rear wall (3) of the rotor housing (1) is designed such that the area (7) behind the spinning rotor (2) is covered inside the rotor housing (1).