Abstract: An open end friction spinning machine is described with a plurality of spinning units which respectively each include two similarly driven, adjacently arranged, friction rollers forming a wedge slot for forming yarn, an inlet and opening device for guiding in individual fibers to the wedge slot, a fiber feed channel connecting the inlet and opening device with the wedge slot, a withdrawal device for withdrawing the formed yarn in the direction of the wedge slot and a suction device to hold the formed and forming yarn in the wedge slot. To facilitate improved start spinning yarn connections, each spinning unit is provided in the region of the ends of the rollers opposite the withdrawal device with a guide element which securely holds the return guided yarn end portion in the region of the fiber feed opening of the fiber feed channel prior to the actual start spinning process.

Abstract: A yarn piecing arrangement is disclosed for an open end friction spinning machine of the type having two friction rollers rotatably drivable in the same direction and disposed adjacent one another to form a yarn forming wedge-shaped gap therebetween, fiber supplying means for supplying individual fibers to the wedge-shaped gap, yarn withdrawal means for withdrawing spun yarn in the direction of the wedge-shaped gap, and suction device means for applying suction forces to hold the spinning yarn in the wedge-shaped gap. In order to facilitate fine control of the yarn piecing process, the friction rollers are stopped before the spun yarn end section is returned to the wedge-shaped gap. Once the yarn end section is positioned at the wedge-shaped gap, the rollers are restarted and yarn piecing is carried out.

Abstract: A spinning aggregate is disclosed for spinning wrapped yarn. A drivable hollow spindle carrys a corotating sleeve with a binding yarn wound on said sleeve, a corotating positive false-twisting device into which the binding yarn and a sliver enter, said sliver being fed by means of a delivery mechanism having a pair of delivery rollers forming a nip, and a pair of withdrawal rollers following the hollow spindle. It is provided that the distance of the false-twisting device from the nip formed by the pair of delivery rollers of the delivery device is shorter than the median staple length of the sliver to be wound.

Abstract: An open end yarn spinning apparatus is disclosed which comprises a plurality of side by side spinning positions, with each spinning position including a circular spinning rotor, and aerodynamic bearings rotatably mounting the rotor. A maintenance carriage is adapted to move along one side of the apparatus, and the carriage mounts a cleaning device which may be introduced into the open side of the rotor upon disengagement of its drive means. To prevent the aerodynamic thrust bearing from being damaged during the cleaning operation by reason of the low speed rotation of the rotor, biasing means is provided for applying an axial force to the rotor to axially separate the thrust bearing and thereby avoid undue wear.

Abstract: An arrangement for open-end friction spinning is disclosed having two adjacently arranged friction rollers driven in the same rotational direction forming a yarn forming wedge shaped gap or slot. A fiber opening device is provided for opening fibers to be spun and a fiber feed channel guides the fibers from the opening device to the yarn forming gap. A yarn withdrawal device is provided for drawing off the produced yarn in the direction of the longitudinal extension of the yarn forming gap. The opening device is configured to simultaneously treat a plurality of fiber bands and the fiber feed channel is divided into several sections in its cross section. The mouths of the feed channel sections are disposed to open to the yarn forming gap at least partially one behind the other along the longitudinal extension of the yarn forming gap.

Abstract: Open end friction spinning apparatus is provided in which there are one or more spinning units with respectively two adjacently arranged rollers, rotating in the same direction, and disposed to form a wedge shaped gap therebetween for accepting fibers and spinning them into a thread of yarn. A housing is provided for each spinning unit, which housing includes a stationary housing part carrying bearing devices for the rollers and a hingedly mounted cover type housing part connected at a pivot axle. The cover type housing part carries at least a part of a feeding channel for feeding fibers to the rollers to be spun.

Abstract: A device for interrupting feed of a roving on a drawing frame, having a feed roller pair, e.g., a powered bottom roller and a top roller tensioned against the bottom roller by springs, includes a clamp for lifting the top roller away from the bottom roller and clamping the roving against the circumference of the top roller. The clamp is disposed on a lever pivotable about an axis parallel to the axes of the feed roller pair and is shiftable with respect to a clamping edge, in the feed direction of the roving, toward the circumference of the top roller. The clamp includes a tongue which initially engages in the nip between the rollers and a portion having a toothed profile which cooperates with the clamping edge by engaging the roving.

Abstract: Apparatus is disclosed for adjustably supporting the friction rollers for an open-end friction spinning unit having two friction rollers that are arranged next to one another and form a wedge-shaped yarn forming gap. The rollers are mounted by means of bearings on non-rotating axles. In the area of the end faces of the friction rollers the non-rotating axles are held by means of holding devices, the spacing of which can be adjusted. Four holding devices arranged in pairs are provided for the axles, where at least between the holding devices of one pair, an adjusting screw is mounted extending transversely to the wedge-shaped gap, by means of which the spacing of said holding devices and thus the size of the wedge-shaped gap, can be adjusted.

Abstract: An open end friction spinning device with two friction rollers driven in the same rotational direction and arranged adjacent one another to form a yarn producing wedge slot is disclosed. Single opened fibers are guided via a fiber feed channel subjected to a transport air stream. To facilitate and improve alignment of fibers in the wedge slot, a suction device for creating an auxiliary air flow in the draw-off direction of the yarn is provided in the area of the mouth of the fiber feed channel.

Abstract: A wrapped-yarn spinning machine having several spinning places which include each a hollow spindle connected with a drive and carrying a binding thread rotating therewith; the hollow spindle is provided with a false twist device and is arranged between a delivery device for a sliver to be wrapped by spinning and a take-off device for the wrapped yarn; a yarn detector is coordinated to the wrapped yarn which detects the yarn tension and is operable to individually shut down the respective spinning place by interrupting the sliver feed and the drive of the hollow spindle in case of a breakage of the binding thread or of the sliver; the false twist device is provided at the inlet end of the hollow spindle while the yarn detector is arranged between the hollow spindle and the take-off device.

Abstract: An open end yarn spinning apparatus is disclosed which comprises a plurality of side by side spinning positions, and which is characterized by the ready accessibility of the internal components of each spinning position without interference with an adjacent position. The apparatus includes a central frame extending longitudinally along the length of the apparatus, and each spinning position includes a frame subassembly composed of two longitudinally spaced apart and transversely directed plate-like side members, and a plurality of longitudinally extending braces which interconnect the two side members. The bearing assembly for the rotor, and the feed and opening rolls are mounted to the frame subassembly, and the rotor housing is releaseably mounted to the frame subassembly so that removal thereof exposes the internal components.

Abstract: Two adjacently arranged friction rollers are disposed to form a yarn forming wedge slot. Cover shells for the rollers are respectively directly carried by roller bearings at an axle. The axles are formed as hollow axles through which a suction flow in the region of the wedge slot is created. The drive for the rollers results by means of a direct tangential belt drive on the surface of the shells in the region of one of the roller bearings.

Abstract: An open end friction spinning machine is disclosed which includes plurality of adjacently arranged spinning units which each have a pair of friction rollers forming a yarn twisting wedge slot. To accommodate cleaning of the friction rollers a mobile servicing cart is provided which is movable longitudinally along the machine to respective servicing positions adjacent spinning units to be cleaned. The servicing cart includes cleaning elements engageable with the rollers to clean them and air suction and blowing devices to assist in the cleaning and removal of contaminants.

Abstract: Open-end friction spinning apparatus is disclosed which includes a plurality of commonly driven spinning units arranged adjacent one another and each including a friction roller pair defining a yarn forming wedge slot therebetween. To facilitate cleaning of the friction rollers, pneumatically operated cleaning nozzles are provided for each friction roller to be cleaned. Some arrangements have the cleaning nozzles fixedly disposed at each spinning unit, with actuating valves being controllable by a mobile servicing unit. In other arrangements the pneumatic cleaning nozzles are carried by a mobile servicing unit and are selectively moved to cleaning positions adjacent the friction rollers of respective spinning units to be cleaned.

Abstract: An open end friction spinning machine is disclosed which is made up of a plurality of adjacently arranged spinning units with respectively two spinning rollers forming a spinning wedge throat or slot and a fiber inlet and opening device. The two spinning rollers are advantageously disposed parallel to another and are arranged in a common bearing housing that forms a first construction unit. A second construction unit is formed by the respective inlet and opening device. These construction units are attached at a machine frame to be independently moveable with respect to one another. Between the two construction units thee is a pivotable intermediate piece, which in its driving position holds both of the construction units in their respective driving position and which automatically brings the construction units out of their driving position upon movement away of the intermediate piece through an adjusting arrangement.

Abstract: A wrapped yarn forming apparatus is disclosed, which is adapted to form a wrapped yarn composed of a core strand, such as a yarn sliver, and a binder strand which is spirally wrapped about the core strand. The apparatus includes a hollow spindle adapted to coaxially mount a supply package of the binder strand, yarn feed means for advancing the core strand through the spindle, and yarn take-up means for winding the resulting wrapped yarn into a package. In the event of yarn breakage, means are provided for interrupting the drives of the various components, and also for terminating the continued withdrawal of the binder strand from its supply package and the continued wind-up of such strand on the take-up package, which would normally occur where only the core strand is broken. Thus piece-up of the apparatus is facilitated by avoiding the necessity of removing the wound binder strand from the take-up package.

Abstract: The disclosure relates to open end friction spinning devices of the type having fibers supplied in an air stream to a yarn forming slot between two friction rollers driven in the same rotational direction. Auxiliary air supply arrangements are described for supplying an air flow to counteract the tendency of fibers to adhere to the friction roller rotating outwardly from the yarn forming slot. These auxiliary air supply arrangements also aid in returning and properly aligning fibers in the yarn forming region of the yarn forming slot.

Abstract: A wrapped yarn spinning machine with several spinning units arranged in a row in side-by-side relationship on at least one side of the machine has a zone of the hollow spindle of each spinning unit, protected by being enclosed within a single closed housing that extends in the longitudinal direction of the machine. The closed housing is provided with a lid at each spinning unit at a front side of the machine. The lid has a height corresponding to at least the height of a side wall of the closed housing and through which binder thread spools, carried by the hollow spindle, can be removed.

Abstract: A wrapped yarn spinning unit equipped with a delivery device for a sliver, a hollow spindle that carries a binding thread to be wrapped about the sliver and rotating together with the hollow spindle, a take-off device for the wrapped yarn, a feed tube between the delivery device and the hollow spindle and an air line connected to the feed tube at a distance downstream of the inlet opening of the feed tube and adapted to be connected to a vacuum source; a twist-producing device is further provided within the area of the inlet opening of the hollow spindle.

Abstract: A yarn package and a method and apparatus for producing the same are disclosed, and wherein the package is composed of a yarn wound in layers of decreasing axial length so as to define a central cylindrical portion and opposite end portions. In order to protectively shield the exposed ends of the yarn layers within at least one of the tapered end portions, the outermost layer is extended so as to overlie and entirely cover such one tapered end portion. In addition, selected intermediate yarn layers may be extended axially a distance sufficient to overlie and cover essentially all of the underlying layers on such one end portion to protect and stabilize the underlying yarn layers.