Abstract: A method for operating a spinning station of a rotor spinning machine includes monitoring the yarn being and upon detection of a yarn defect, stopping the spinning station and removing the yarn defect. The method specifies a certain produced yarn length or a certain time interval of yarn production and a maximum number of yarn defects within the produced yarn length or time interval. Upon detecting and exceeding a maximum number of yarn defects within the produced yarn length or the time interval, a mechanical cleaning of the spinning rotor is carried out. Alternately, a certain minimum produced yarn length or a certain minimum time interval between two yarn defects is specified and the produced yarn length or time between detection of the yarn defects is recorded. Upon undershooting the minimum produced yarn length or minimum time interval between yarn defects, the mechanical cleaning of the spinning rotor is performed.

Abstract: A cleaning device for cleaning a rotor disk of a spinning rotor has a cleaning head with at least one cleaning element, and a receptacle on which the cleaning head is mounted and which can be fed to the spinning rotor for cleaning the rotor disk. The cleaning head includes at least one bearing area by means of which the cleaning head is mounted on the receptacle. A longitudinal direction of the bearing area defines an axial direction of the cleaning head. The cleaning head is mounted in the axial direction in a floating manner on the receptacle, and/or the cleaning element is mounted in the axial direction in a floating manner on the cleaning head.

Abstract: 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.

Abstract: An open-end spinning machine and control method are provided for cleaning a spinning rotor of a spinning device in which at least one cleaning measure is carried out on the spinning rotor with the aid of a pneumatic or a mechanical cleaning device. With a control unit associated with the open-end spinning machine, settings are specified for the cleaning device to carry out the cleaning measure, wherein the settings are empirically determined based on one or more operational parameters of the spinning rotor. Operational parameters are stored in a memory bank associated with the control unit. The specific settings for carrying out the cleaning measure for a particular spinning rotor are automatically determined by reference to the operational parameters stored in the memory bank that are applicable to the particular spinning rotor.

Abstract: A thread guide unit is used for drawing off a thread out of a rotor of a spinning unit of an open-end spinning machine. The thread guide unit includes a draw-off tube, and a compressed air nozzle configured with the draw-off tube. A thread outlet element extends into the draw-off tube. The compressed air nozzle includes a mouth formed as a gap between an inner diameter surface of the draw-off tube and the thread outlet element. A method for operating a spinning unit of an open-end spinning machine having the thread guide unit is also provided.

Abstract: 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.

Abstract: 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.

Abstract: In a method for cleaning a spinning rotor (4) of a spinning device (1) of an open-end spinning machine, at least one cleaning measure (RM) is carried out on the spinning rotor (4) with the aid of a pneumatic and/or a mechanical cleaning device (7), wherein settings (E), with the aid of which the at least one cleaning measure (RM) is carried out, are predefined by a control unit (24) of the open-end spinning machine. Various parameter (P) are stored in a memory bank (25). Moreover, previously empirically determined settings (E) for carrying out the cleaning measure (RM), which are suitable for the particular parameters (P), and/or rules (R) for determining settings (E) which are suitable for the particular parameters (P) are stored. The settings (E) for carrying out the at least one cleaning measure (RM) are automatically determined by the control unit (24) with the aid of the memory bank (25) depending on presently given parameters (P).

Abstract: A cleaning head of a cleaning device for cleaning a spinning rotor, by means of a feed device, be fed into a predetermined cleaning position in the interior of the spinning rotor. The cleaning head has a cleaning element formed as a scraper element arranged in such a manner that, in the predetermined cleaning position of the cleaning head, it is fed to the open edge of the spinning rotor. A cleaning device for cleaning a spinning rotor features a corresponding cleaning head. With a method for cleaning a spinning rotor by means of the cleaning device, after feed of the cleaning head into the cleaning position, the open edge of the spinning rotor is cleaned by means of the scraper element.

Abstract: A method and associated spinning machine for maintaining spinning units of the spinning machine includes a plurality of the spinning units arranged next to one another and at least one maintenance device that is movable along the spinning units to perform maintenance procedures on the spinning units. Prior to maintenance of a spinning unit by the maintenance device, a housing of the spinning unit is opened. Subsequently, the maintenance is performed and then the housing is closed. One or both of the opening and the closing of the housing is carried out autonomously with a sealing device operably configured at the spinning unit.

Abstract: A cleaning device (1) for cleaning a rotor disk (2) of a spinning rotor (3) features a cleaning head (4), which features at least one cleaning element (5a, 5b) for cleaning the spinning rotor (3), and one receptacle (6), in which the cleaning head (4) is mounted and which can be fed to the spinning rotor (3) for cleaning. The cleaning head (4) features at least one bearing area (7), the longitudinal direction of which defines an axial direction (AR) of the cleaning head (4). The cleaning head (4) is stored in an axial direction (AR) in a floating manner on the receptacle (6) and/or the at least one cleaning element (5a, 5b) is stored in an axial direction in a floating manner on the cleaning head (4).

Abstract: This invention relates to a thread guide unit (6) for drawing off a thread (4) from a rotor (2) of a spinning unit (1) of an open-end spinning machine with a draw-off tube (18) and a compressed air nozzle (21). In accordance with the invention, it is proposed that thread outlet element (19) is provided, a thread outlet element (19) is provided and a mouth (23) of the compressed air nozzle (21) is formed as a gap between the draw-off tube (18) and the thread outlet element (19). The invention also relates to an open-end spinning machine with a multiple number of spinning units (1), whereas each spinning unit (1) features a spinning assembly (3), a thread guide unit (6) in accordance with the preceding description, draw-off rollers (5), a spooling unit (9, 11) and a thread setting unit (15, 14, 16).

Abstract: With a method for preparing a yarn end (9) for spinning in at a rotor spinning device (2) of a rotor spinning machine (1) with a rotor housing (3) that can be closed with a cover (4) and can be subjected to negative pressure through a negative pressure channel (8), with a spinning rotor (5) that is rotatably mounted in the rotor housing (3) and rotates with an operating rotational speed during the spinning operation along with a draw-off nozzle (7), the yarn end (9) to be prepared is introduced into the negative pressure channel (8), and is interrupted by a severing structure (10) of the open edge of the rotating spinning rotor (5), and is thereby prepared for spinning in.

Abstract: A cleaning head (1) of a cleaning device (2) for cleaning a spinning rotor (3) featuring a fiber slide wall (4), a fiber collection groove (5) and an open edge (6) can, by means of a feed device of the cleaning device (2), be fed into a predetermined cleaning position (I) in the interior of the spinning rotor (3). The cleaning head (1) features at least one cleaning element formed as a scraper element (7), which is arranged on the cleaning head (1) in such a manner that, in the predetermined cleaning position (I) of the cleaning head (1), it is fed to the open edge (6) of the spinning rotor (3). A cleaning device (2) features a corresponding cleaning head (1) for cleaning a spinning rotor (3). With a method for cleaning a spinning rotor (3) by means of a cleaning device (2), which features such a cleaning head (1), after the feed of the cleaning head (1) into the cleaning position, the open edge (6) of the spinning rotor (3) is cleaned by means of a scraper element (7).

Abstract: For the piecing of a yarn in an spinning device, various computation formulas are stored in a control device into which calculated values as well as special data converted into numerical values relating in particular to the fiber material, the yarn and the spinning element are first entered to compute and select settings for operations relevant to the piecing process. A feeding device feeding a fiber sliver to the spinning device is first brought to a high pre-feeding speed by means of such pre-programmed values and converted data. From this pre-feeding speed, the feeding speed is greatly decelerated in steps to its piecing feeding speed in coordination with the release of the yarn to be fed back into the spinning element.

Abstract: A procedure and apparatus for start-up spinning of a thread in an open-end spinning apparatus is provided. A first and second auxiliary roll-pair are presentable within a thread course during start up spinning. A source of a suction air stream within the spinning apparatus is positioned below the first and second roll-pairs. The source of suction air stream creates a suction flow of air to induce the thread end into the spinning apparatus for start up spinning. A control center is in communication with the first and second roll-pairs, so that the control center controls them. A thread storage unit is positioned between the first and second roll-pairs proximal to the course of the thread. The thread storage unit is in communication with the control center so that the thread storage unit is activated to store and release the thread during start up spinning.

Abstract: For the piecing of a yarn in an spinning device, various computation formulas are stored in a control device into which calculated values as well as special data converted into numerical values relating in particular to the fiber material, the yarn and the spinning element are first entered to compute and select settings for operations relevant to the piecing process. A feeding device feeding a fiber sliver to the spinning device is first brought to a high pre-feeding speed by means of such pre-programmed values and converted data. From this pre-feeding speed, the feeding speed is greatly decelerated in steps to its piecing feeding speed in coordination with the release of the yarn to be fed back into the spinning element.

Abstract: Upon the start of spinning a thread (F), two auxiliary roll-pairs (20, 21) bring an end (E) of the concerned thread into a preparatory position (P) within an entrainment zone of a suction induced air stream, which stream enters an open-end spinning apparatus (10). At this point, in order to uphold the continuity of the thread, the said auxiliary roll-pairs (20, 21) are stilled in their revolution. With renewed drive, the second roll-pair (21), located more distant from the open-end spinning apparatus (10), causes a reversely directed thread movement, whereby, between the two said roll-pairs (20, 21), a thread surplus is created. This thread accumulation between the roll-pairs 20, 21 is retained in a pneumatic thread storage unit (23). The second auxiliary roll-pair (21) is then stopped from further rotation. The first auxiliary roll-pair (20), proximal to the open-end spinning apparatus (10), now opens itself, thus freeing its clamp on the thread.

Abstract: The rotor cover (2) of an open-end spinning machine possesses a projecting cover cap (3) with a side recess (4), which, on its end remote from the rotor cover is bordered by a collar (40). This possesses both in the partial zone of its circumferential area containing the collar (40), and in the remaining circumferential zone, essentially the same outer contour. The recess (4) begins, relative to the direction of rotation (f) of the spin rotor 1, between 30° and 130° after the discharge opening (50) of the fiber feed conduit (5) and ends at a section of the of the wall (51) protruding from the radial surface (20) of the rotor cover (2). The recess (4) extends to a radial surface (20) of the rotor cover (2) which radial surface (20) covers the open side of the spin rotor.

Abstract: A roller for a belt stretching mechanism of a spinning machine has edge regions, a central zone which is depressed relative to the edge regions, and a radially movable sleeve located in a region of the central zone.