A method for producing a rotor cup for an open-end spinning rotor includes forming separating structures on a front-side rim of the rotor cup for breaking up and preparing a yarn end for piecing. The separating structures are formed by a non-mechanical manufacturing method without contact between the front-side rim and a mechanical forming tool. A rotor cup formed in accordance with the method is also provided.

A cleaning device (1) for cleaning a rotor plate (2) of a spinning rotor (3) comprises a receptacle (6), a cleaning head (4) mounted on the receptacle (6), which can be advanced toward the spinning rotor (3) for cleaning and which includes at least one cleaning element (5, 5a, 5b), and comprising a brake device (11) for decelerating and/or holding the spinning rotor (3) once the cleaning head (4) has been advanced. The cleaning head (4) comprises an at least partially cylindrical receiving area (7) for the spinning rotor (3), which defines an axial direction (AR) and a radial direction (RR) of the cleaning head (4). The brake device (11) contains multiple, in particular two, brake elements (12), which are mounted on the cleaning head (4) in such a way that they are movable from a neutral position into a braking position, and each of the multiple brake elements (12) is movable with the aid of its own drive (13).

A rotor spinning machine and associated method are provided for preparing a yarn end for spinning-in at a rotor spinning device, wherein the rotor spinning machine has a rotor housing that is closable with a cover and subjected to negative pressure through a negative pressure channel. A spinning rotor is rotatably mounted in the rotor housing and rotates with an operating rotational speed during a spinning operation. With the method, the yarn end is introduced into the negative pressure channel. The yarn end is then interrupted with a severing structure defined on an open edge of the rotating spinning rotor. During the interruption of the yarn end, the spinning rotor is driven with a defined rotational speed for the preparation of the yarn end that is equal to or less than an operating rotational speed of the spinning rotor.

A rotor spinning machine and associated method are provided for preparing a yarn end for spinning-in at a rotor spinning device, wherein the rotor spinning machine has a rotor housing that is closable with a cover and subjected to negative pressure through a negative pressure channel. A spinning rotor is rotatably mounted in the rotor housing and rotates with an operating rotational speed during a spinning operation. With the method, the yarn end is introduced into the negative pressure channel. The yarn end is then interrupted with a severing structure defined on an open edge of the rotating spinning rotor. During the interruption of the yarn end, the spinning rotor is driven with a defined rotational speed for the preparation of the yarn end that is equal to or less than an operating rotational speed of the spinning rotor.

A method for operating a textile machine with several identical workstations which each have a basic requirement for negative pressure for regular production operation and an additional requirement for negative pressure following an interruption to production at the workstation, and with a vacuum system with limited suction force to exert the negative pressure on the workstations. A minimum negative pressure (p.sub.min) is set and the number workstations simultaneously supplied with additional negative pressure is limited so that the minimum negative pressure (p.sub.min) is always met. In accordance with the invention, a sub-negative pressure (p.sub.sub) is specified which is below the minimum negative pressure (p.sub.min) and, if a specified event occurs, the number of workstations simultaneously supplied with additional negative pressure is temporarily limited so that the sub-negative pressure (p.sub.sub) is always met.

A method for operating a textile machine with several identical workstations which each have a basic requirement for negative pressure for regular production operation and an additional requirement for negative pressure following an interruption to production at the workstation, and with a vacuum system with limited suction force to exert the negative pressure on the workstations. A minimum negative pressure (p.sub.min) is set and the number workstations simultaneously supplied with additional negative pressure is limited so that the minimum negative pressure (p.sub.min) is always met. In accordance with the invention, a sub-negative pressure (p.sub.sub) is specified which is below the minimum negative pressure (p.sub.min) and, if a specified event occurs, the number of workstations simultaneously supplied with additional negative pressure is temporarily limited so that the sub-negative pressure (p.sub.sub) is always met.

A method for automatically piecing a thread at a workstation of a textile machine, includes seeking an end of the thread on a surface of a bobbin with a suction nozzle and unwinding the thread from the bobbin counter to a regular draw-off direction of the thread and sucking the thread into the suction nozzle. The bobbin is driven in a direction of reverse rotation with a drive. A thread loop is draw-opened in the thread and moved towards a piecing unit via movement of a feeder unit. The bobbin is driven in the direction of reverse rotation during the drawing-open of the thread loop such that the thread is unwound from the bobbin. A speed of reverse rotation of the bobbin is coordinated with movement of the feeder unit.

A method for automatically piecing a thread at a workstation of a textile machine, includes seeking an end of the thread on a surface of a bobbin with a suction nozzle and unwinding the thread from the bobbin counter to a regular draw-off direction of the thread and sucking the thread into the suction nozzle. The bobbin is driven in a direction of reverse rotation with a drive. A thread loop is draw-opened in the thread and moved towards a piecing unit via movement of a feeder unit. The bobbin is driven in the direction of reverse rotation during the drawing-open of the thread loop such that the thread is unwound from the bobbin. A speed of reverse rotation of the bobbin is coordinated with movement of the feeder unit.

Method for operating a service unit for processing work orders regarding a cross-wound package/empty tube doffing process employed at spinning machines producing take-up packages that process at least two different lots, whereby the service unit is fed an empty tube via the spinning machine's tube feed track, and the fed empty tube is taken up by the service unit. If the current work order for the cross-wound package/empty tube doffing of the workstations expires before it is processed and the empty tube is exchanged and another work order has come in which is for a workstation requiring a cross-wound package/empty tube doffing for another lot, the already taken up empty tube is released by the service unit, and the service unit takes up an empty tube of another lot in order to be able to carry out a cross-wound package/empty tube doffing process at the other workstation.

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.