Abstract: Traversing yarn guiding rods in textile machines producing X-packages are often made of carbon fibers for the purpose of reducing the inertia force. These kinds of traversing yarn guiding rods are prone to wear at their bearing points. For this reason, the bearings, having a distance to one another which corresponds to at least twice, preferably three times the traversing stroke, are collectively replaced from time to time, in such a way that the yarn guide rod is supported at different places than before. The replacement bearings are applied staggered to the old bearing points in such a way that the new bearing points now have a distance to the exposed previous bearing points, which distance corresponds to at least one traverse stroke. This results in the replacement bearings acting with a non-worn part of the fiber guiding rod. The life of the yarn guiding rod is thus significantly increased.

Abstract: The present invention relates to a fine-toothed combing structure of an opening roller for an open-end spining machine. The teeth of the fine-toothed combing structure have a spacing which measures at least three times the height of the teeth. The front angle should not measure more than 10°. This fine-toothed combing structure is preferably used for synthetic fibers.

Abstract: A condensing zone for condensing a drafted, still twist-free fiber strand is arranged downstream of a front roller pair of a drafting unit of a spinning machine. An air-permeable transport belt transports the fiber strand through the condensing zone. The transport belt slides hereby over a stationary sliding surface, in which a suction slit of a suction channel is located. At the end of the condensing zone, the fiber strand is pressed with the transport belt by a nipping roller to the sliding surface. The nipping roller as well as the front pressure roller of the drafting unit are supported in a top weighting arm. A separate pressure spring is arranged each for the top pressure roller and for the nipping roller. It can be provided that the nipping roller is arranged at a holding device, which can be swivelled around a swivel axle, which lies coaxially to the axle of the front pressure roller.

Abstract: In a process for condensing a drafted fiber strand in a condensing zone arranged downstream of a front roller pair of a drafting apparatus, the fiber strand is transported through the condensing zone by means of a perforated, suctioned transport belt. It is hereby provided that the fiber strand has the same direction of motion as the transport belt. Furthermore, it is ensured that a sufficient amount of the fibers located in the fiber strand are still nipped by the front roller pair during condensing. This results in the advantage that the front ends of the fibers of the fiber strand to be condensed do not insert themselves into the perforation of the transport belt, thus leading to clogging.

Abstract: A yarn withdrawal nozzle for an open-end rotor spinning apparatus comprises a short, funnel-shaped yarn deflecting surface, which begins at a plane front surface and graduates into a yarn withdrawal channel. The radius of curvature of the yarn deflecting surface measures a maximum of 3 mm. The front surface is formed as a tangential surface to the yarn deflecting surface, The small radius of curvature facilitates in particular the spinning of polyester yarns at a high rotor speed.

Abstract: A condensing zone for condensing a drafted fiber strand is disposed downstream of a front roller pair of a drafting unit of a ring spinning machine. The condensing zone comprises a stationary sliding surface having a suction slit, over which the fiber strand is transported by an air-permeable transport belt. The condensing zone is bordered on its exit side by a nipping roller disposed on the transport belt. The nipping roller drives the transport belt and is in turn driven by the front pressure roller of the drafting unit. The front pressure roller is, for this purpose, connected with the nipping roller via a drive belt, preferably a toothed belt. The nipping roller and the front pressure roller are arranged on supporting arms which can be spread apart and which tension the drive belt.

Abstract: A condensing zone for condensing a drafted, still twist-free fiber strand is arranged downstream of a front roller pair of a drafting unit of a spinning machine. An air-permeable transport belt transports the fiber strand through the condensing zone. The transport belt slides hereby over a stationary sliding surface, in which a suction slit of a suction channel is located. At the end of the condensing zone, the fiber strand is pressed with the transport belt by a nipping roller to the sliding surface. The nipping roller as well as the front pressure roller of the drafting unit are supported in a top weighting arm. A separate pressure spring is arranged each for the top pressure roller and for the nipping roller. It can be provided that the nipping roller is arranged at a holding device, which can be swivelled around a swivel axle, which lies coaxially to the axle of the front pressure roller.

Abstract: An air-permeable transport belt, drivable by a drive roller, is provided for transporting a fiber strand to be condensed over a sliding surface of a spinning machine condensing zone which includes a suction slit. The transport belt has at least one area arranged to contact the drive roller, which area differs in relation to its surface structure from an area arranged to contact the sliding surface and from an area arranged to contact the fiber strand.

Abstract: In order to transport a fiber strand to be pneumatically condensed over a suction slit of a condensing zone of a spinning machine, a transport belt is provided which comprises, at least in the effective area of the suction slit, a porous area. The porous area can, for example, be created by dissolving granulate components from a fine-grained granulate blend.

Abstract: An arrangement and method for spinning a yarn from a plurality of yarn components includes a drafting arrangement, a condensing zone arranged downstream thereof and also a ring spindle which twists all yarn components jointly. The condensing zone has a stationary sliding surface for a perforated transport belt which transports the yarn components through said condensing zone. At least one suction slit is located on the sliding surface, which suction slit extends essentially in a transport direction of the yarn components. The condensing zone is defined on its exit side by a nipping roller, which presses the yarn components and the transport belt onto the sliding surface. The at least one suction slit extends to the nipping point. The yarn components may be a sliver or roving and a core yarn, or two slivers or rovings, which, with or without any core yarn, together form the subsequent yarn.

Abstract: A condensing zone for pneumatic condensing of the drafted, still twist-free fiber strand is arranged downstream of the drafting apparatus of a ring spinning machine. The condensing zone is limited by a delivery roller pair, whose driven bottom roller is a suction roller, which is arranged directly downstream of the front roller pair of the drafting apparatus. The fiber strand loops the suction roller at an angle of at least 45°.

Abstract: A condensing zone for condensing a drafted twist-free fiber strand is arranged downstream of a drafting arrangement of a ring spinning machine. The condensing zone includes a stationary sliding surface having a suction slit extending essentially in a fiber strand transport direction. A perforated transport belt transports the fiber strand over the suction slit of the sliding surface. The transport belt wraps around a bottom roller of a front roller pair of the drafting arrangement and is driven by the bottom roller. The transport belt drives in turn a nipping roller, which limits the condensing zone on its exit side with a nipping point serving as a twist block. The nipping roller presses the fiber strand and the transport belt against the sliding surface of the condensing zone.

Abstract: An arrangement for condensing a drafted fiber strand is arranged at each spinning station of a spinning machine. The condensing arrangements each comprise a transport surface which transports the fiber strand over a suction slit of a suction device. A joint suction device having its own fan is provided for a certain number of spinning stations so that differences in underpressure between the individual spinning stations are avoided to a great extent.

Abstract: A process for open-end spinning provides for at least one sliver being opened into single fibers. A wide fiber veil is formed from parallel single fibers extending in the direction of motion, which fiber veil is fed to a transporting surface by means of a moving collecting surface. The single fibers are transferred from the collecting surface to the transporting surface at a transfer point, whereby the direction of motion of the fiber veil is abruptly changed, however the current relative position of the single fibers remaining essentially constant. This motion direction change occurs at the transfer point, with the respective front part of the fiber veil being transferred to the transporting surface as a fiber group in a predetermined sequence, and the transporting surface moves transversely to the direction of motion of the collecting surface.

Abstract: A procedure is described in which an open-end rotor spinning machine already in operation can be modernized by means of re-equipping it with new parts. This machine comprises device means for interrupting the spinning process at a spinning station for the purpose of a doffing operation. The machine comprises a doffing arrangement which is movable relative to the spinning stations, which doffing arrangement comprises devices for exchanging a full bobbin for an empty yarn-winding tube. The machine comprises further at least one piecing arrangement movable in relation to the spinning stations, which is designed to restart spinning at the spinning station with a starting winding already connected to the yarn-winding tube. It is an object of the modernization that the piecing arrangement is replaced with a new piecing arrangement, which is designed to restart spinning with a starting yarn which is not connected to the yarn-winding tube, and subsequently to attach a newly spun yarn to the yarn-winding tube.

Abstract: An open-end spinning machine comprises a plurality of adjacently arranged spinning aggregates. Each spinning aggregate consists essentially of a rotor unit comprising a spinning rotor, and an opening unit for opening a fed sliver into single fibers. The opening unit and the rotor unit each comprise a plurality of components. In order to modernize the open-end spinning machine, at least one of the above mentioned components is replaced by at least one modernized component in such a way that the efficiency of the spinning aggregate is improved.

Abstract: A draft free condensing zone for condensing a drafted fiber strand is provided between a front roller pair of a drafting unit of a ring spinning machine and a delivery roller pair arranged downstream thereof. The apparatus for condensing comprises an air-permeable und suctioned sliding surface which is in contact with the fiber strand, under which sliding surface is located a suction slit which is stationarily arranged and extends essentially in transport direction of the fiber strand. The sliding surface is the front surface of a rotating disc, whose rotational axle extends essentially perpendicular to the transport direction of the fiber strand.

Abstract: The fiber sliding surface and the fiber collecting groove of an open-end spinning rotor are provided with hard particles embedded therein. After a certain length of operation time of the spinning rotor, the particles in the fiber collecting groove have a larger particle size than the particles in the fiber sliding surface. Thus it is ensured that the fiber collecting groove has a better "grip effect" relative to the fibers to be spun than the smoother fiber sliding surface.

Abstract: In the case of a rotor cup for an open-end spinning aggregate comprising a rough-surfaced fiber collecting groove and a smooth fiber sliding surface it is provided that hard particles are rolled into the fiber collecting groove. The fiber collecting groove is preferably provided with a soft nickel plating before the particles are rolled in, after which the nickel plating is then hardened.

Abstract: In the case of an arrangement for open-end spinning, a driven suction roller is provided which in a take-up zone takes up fiber material opened to single fibers and transports it to a suctioned yarn formation line. The yarn formation line is defined by a suction insert arranged in the inside of the suction roller, and extends transversely to the transport direction of the suction roller on the surface thereof. In extension of the yarn formation line a twist device is provided. On the side facing away from the twist device, the suction roller is supported on the suction insert while freely overhanging same, so that the twist device reaches directly up to the suctioned yarn formation line. The yarn formation line is preferably inclined at an angle towards the take-up zone on the side facing away from the twist device.