Abstract: A piecing device with an evaluation arrangement for determining parameters of an automatic piecing process at a spinning station (1) of an open-end spinning frame, wherein a control device is provided which, initially in a test phase, controls the creation of at least one test piecing without a supplementary delivery of additional fiber and the subsequent removal of the created test piecing. The evaluation device is designed for determining the length of a thinner extent of the test piecing downstream of the test piecing as viewed in the direction of yarn travel, and for the determination from the detected length of the thinner extent an amount of supplementary delivery of additional fiber required for compensating the thinner extent. A reduction of the draft which is effective during the test phase assures an interference-free checking of the test piecing. The optimization phase for piecings is shortened and leads to a more accurate result when determining the supplementary delivery of additional fiber.

Abstract: The supporting disks for supporting disk bearings of open-end spinning rotors comprise a tire or ring with damping properties, as well as an essentially cylindrical running surface. In order to avoid heat build-up, the running surface is interrupted by two grooves, thus dividing the running surface into one inner and two outer sectional surfaces. The outer sectional surfaces are each wider than the inner sectional surface by 20 to 40%.

Abstract: The invention relates to a method and a device for preventing mass fluctuations in fiber material (1) which is processed in a spinning process using a rotor (10) to form a yarn (3). To this end, the mass fluctuations in the fiber material are detected in the immediate vicinity of the rotor and elements (6, 7, 12) which are drive-connected therewith, and are reduced by a control intervention.

Abstract: In the case of a method for closed-loop controlling the revolutions of an open-end spinning rotor during automatic piecing, the spinning rotor is run up to its operating speed from a standstill by being coupled to a tangential drive belt, which runs at operating speed. The spinning rotor thereby passes through a suitable speed range for piecing, and is kept at this speed range for a predetermined time span by changes in the driving effect of the tangential drive belt. This occurs in that the revolutions of the spinning rotor are measured, and dependent on these readings, the revolutions are closed-loop controlled by device of reducing and increasing the driving effect, for example by device of intermittent activating of the rotor brake.

Abstract: A process for introducing a fiber sliver into a fiber processing machine which has an openable sliver feeding device and a sliver introduction funnel and a sliver injector, comprising the following steps: opening the openable sliver feeding device, grasping the leading end of the sliver pneumatically into and through the sliver introduction funnel and into the opened feeding device and closing the sliver feeding device on the sliver. The invention also includes a device for carrying out the process.

Abstract: A textile machine for processing sliver includes a plurality of work stations disposed side by side. Each of the work stations has a respective fixedly assigned parking place. Sliver cans are each disposed on a respective one of the parking places behind one another in at least two rows for supplying the work stations with sliver. An automatic can changer replaces any of the sliver cans that have become empty with filled sliver cans. A device monitors contents of the sliver cans and recognizes a sliver interruption when the sliver cans are still partly full. The work stations have sliver delivery devices and the work stations include given work stations. The sliver delivery devices of the given work stations each have a device for permitting sliver supply to a respective one of the given work stations only from a sliver can located on the fixedly assigned parking place of the respective one given work station.

Abstract: A spinning or twisting device in which a yarn is to be back-fed into the bore of a pipe-shaped element subjected to negative pressure in order to repair a yarn break. This pipe-shaped element is made in form of a yarn draw-off pipe of an open-end spinning device or as part of a pneumatic twisting device.A presenting device is moved over and beyond the pipe-shaped element into a yarn inserting position. The end of the pipe-shaped element towards the moving path of the presenting device is provided with a nozzle which is provided, in relation to the bore, on its side towards the yarn inserting position of the presenting device with a yarn support, and on its side away from the yarn inserting position with a yarn insertion groove, oriented in the direction of movement of the presenting device. The bottom of the yarn insertion groove is at a greater distance from the moving path of the presenting device than the yarn support.

Abstract: In a device for the piecing of a yarn on an open-end spinning device, a yarn mover by means of which a yarn end is fed to a yarn draw-off pipe is provided. A first stop to determine the cutting position and a second stop to determine the yarn insertion position are assigned to the yarn mover. The first stop can be put out of action. In addition, a yarn length adjusting device is provided to determine the length of yarn to be fed back into the open-end spinning element. The cutting position and the yarn insertion position of the yarn mover are set for the smallest size fiber collection surface of the open-end spinning element that can be used. When larger fiber collection surfaces are used, the additional required length of yarn is readied by rotating the winding device backward.

Abstract: A method and apparatus for stopping and subsequently restarting an open end spinning machine wherein, upon an electrical power interruption exceeding a predetermined duration, the spinning rotor, sliver feed roller, yarn take-up roller, and yarn winding drum are deactuated, the yarn take-up roller and winding drum are braked to a standstill, and the length of withdrawn yarn during braking is measured and stored, and, upon restarting of the machine, the sliver feed roller is briefly operated to initially deliver a start-up sliver length to the rotor and yarn take-up roller and yarn winding drum are operated in reverse to feed back to the rotor a length of withdrawn yarn corresponding to the measured and stored yarn length in advance of reactuation of the spinning operation.

Abstract: An open-end rotor spinning apparatus is provided which includes at least one spinning unit having yarn deflecting elements downstream from a yarn withdrawal duct. The yarn deflecting elements deflect yarn from the yarn withdrawal duct in a yarn spinning path. The yarn deflecting elements include at least one false-twisting edge. Yarn returning elements are provided for returning a yarn end to the yarn withdrawal duct past the yarn deflecting elements in a piecing path having a deflection less than the yarn spinning path deflection.

Abstract: An open-end spinning machine includes a low inertia sensing wheel frictionally engaging the package so that the rate of rotation of the frictional sensing wheel is sensed by a tachometer generator to provide a "winding rate" signal fed to a controller for controlling the speed of a stepper motor driving the fibre feed roller of the fibre opening unit during piecing, in response to the take-up of yarn at the package. Optionally, the sensing wheel is supported on a link such that the angular position of the link indicative of the diameter of the package is sensed by an angular position transducer and the signal of the transducer is also fed to the controller.Yarn delivery rolls are separated, during piecing, to allow the rate of withdrawal of the yarn from the doffing tube of the open-end spinning unit in response solely to the accelerating package.The draft is non-linear during piecing, in accordance with a predetermined programme.

Abstract: An open-end rotor spinning machine includes a plurality of spinning stations each including a first thread monitor monitoring a thread course and a rotor spinning device receiving a fiber supply and having a spinning element; an automatic thread joining device for joining a thread to be conducted to the rotor element, and a second thread monitor disposed on the automatic thread joining device for monitoring the thread course without placing a load on the thread when the first thread monitor is inoperative and the automatic thread joining device is operative, the automatic device delivering the second thread monitor and a thread to a location directly adjacent the spinning element, and the second thread monitor including a device for immediately interrupting the fiber supply to the rotor spinning device if the second thread monitor detects the absence of the thread.

Abstract: In the case of a supporting roller bearing for a horizontally arranged spinning rotor, it is provided that braking means are arranged below a tangential belt moving between two pairs of supporting roller. The braking means contain two brake shoes that can be applied essentially horizontally to the shaft from the direction of two sides, said brake shoes being arranged on tong arms. The applying of the brake shoes takes place in such a way that the brake shoe that during the application moves in moving direction of the tangential belt comes to rest against the shaft before the other brake shoe. In addition, it is provided that a tension roller loading the tangential belt in normal operation, during the braking, will not be moved off the tangential belt before both brake shoes are applied to the shaft.

Abstract: Drive to the sliver feed roll of a fibre-opening unit of an open-end spinner is interrupted by de-activation of a clutch and simultaneously further rotation of the input shaft of a worm and pinion mechanism is blocked against further rotation by release of a spring finger into the path of peripheral teeth on a disc.Upon a yarn break sensed by a detector, the clutch is de-energized and the spring finger released to arrest and lock the disc.

Abstract: A continuous process of making a blended yarn of staple fiber and long-fiber or filamentary material in which the long-fiber or filamentary material is passed through a rupture zone to produce lengths thereof which are fed directly into an air stream with the staple fibers to produce an intimate blend which is conveyed by the air stream directly to an open end spinning device which produces the yarn.

Abstract: The travelling piecer carries a lever to separate the nip rollers, a yarn reserve forming device to receive the yarn and a threading device for threading a broken yarn from a package between the nip rolls and through the yarn reserve forming device. The piecer also has a control which effects a piecing operation in which a clutch is actuated to feed fiber into the spinning unit while yarn is back-fed into the unit from the yarn reserve. At the completion of a predetermined time period (T) the nip rolls are re-engaged to withdraw the re-pieced yarn.

Abstract: In preparation for the start of spinning with an open-end spinning apparatus, suction is provided outside a fiber transport path on the periphery of an opening roller. Such suction is greater than spinning suction which exists at the mouth of a feed channel leading to the fiber-collecting surface. The fiber stream is thereby guided beyond such mouth to be sucked off. At commencement of actual spinning, this added suction is inactivated, to permit the fiber stream to be initially supplied to the fiber-collecting surface. The fiber stream may be controlled with a suction source connected to a sucking-off orifice via a switching device and a suction line. Less conspicuous and more even thread joins are thereby obtained. Control of suction changes may be effected automatically from a servicing trolley, or in other manners.

Abstract: The travelling piecer is provided with a threading pin which moves through an endless path in order to thread a seed yarn through the nip rolls of a spinning station and a yarn reserve forming device.The yarn centering mechanism employing a pair of pivotally mounted guide arms is used to position an accessible length of seed yarn in a position to be taken up by the threading pin.

Abstract: In the case of an open-end friction spinning machine having a plurality of spinning units that are arranged next to one another and having a movable servicing apparatus carrying out a piecing process, it is provided that approximately in the extension of the yarn formation zone facing away from the withdrawal device, a twist blocking device is provided for receiving a yarn end that is returned beyond the feeding point. The device for the yarn withdrawal is switched on when the yarn end is in the yarn formation zone of the friction elements so that the yarn end is opened up into a fiberbeard that is suitable for piecing while being held by the twist blocking device.

Abstract: This invention relates to an apparatus for emergency fiber supply to a spinning unit in an open-end spinning machine. According to the invention, a sensing unit controls an electromagnetic coupling and fiber supply device, such that a break in the yarn is rapidly detected and the fiber supply is immediately disengaged, even if the conventional thread breakage detector fails.A sensing unit is disposed in that portion of the wall of a cover that extends into the spinning rotor interior. It is adapted to respond to the excess accumulation of unspun fibers and/or an undue increase in temperature by disconnecting the electromagnetic fiber supply coupling via the thread breakage detector circuit to which it is connected. The sensing unit can be a pressure sensitive microswitch, a bimetallic relay, a thermistor, or a combination of these elements.

Abstract: A process and apparatus for piecing a yarn at a spinning unit of an open-end friction spinning machine is disclosed. Before the return of the yarn end, the wedge-shaped yarn forming gap is exposed by moving away a lid-type component containing at least one part of the fiber feeding channel, after which the yarn end is introduced into the mouth of the fiber feeding channel of this lid-type component, and subsequently, the lid-type component is returned to its position covering the wedge-shaped gap. Subsequently, the actual yarn piecing process is carried out by switching on the yarn withdrawal device and the yarn feeding device as well as by the transfer of the end of the yarn end to the wedge-shaped gap.

Abstract: A process and apparatus is disclosed for improving the start-spinning of yarn on an open end friction spinning machine. To facilitate an exact alignment of the return yarn end to be pieced up with newly supplied incoming fibers, the respective spinning units are provided with a moveable cover part which in the open position exposes the yarn forming wedge slot between the friction rollers. Devices are provided for returning the yarn end and holding the same at a slight spacing from the friction rollers at the wedge slot and for sequentially timing the yarn draw off during start spinning with the activation of the fiber feed and the suction air flow related thereto.

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: In an open-end spinning apparatus with an opening roller 2 and a supply device 1, a sliver clamp 5 associated with the supply device 1 is provided to interrupt the sliver feed and can be actuated when the supply roller 10 continues to run by a yarn monitor 31 or a lap monitor 12. In the fiber transport direction, a further, second sliver clamp 6, actuable simultaneously with the first sliver clamp 5 is arranged in front of the supply device 1 at a distance which is as large as the average staple fiber length. Preferably the moving part 62 of the further sliver clamp 6 is rigidly connected to the clamping lever 53 of the first sliver clamp 5.

Abstract: The invention relates to an apparatus for the spinning-in of yarns in an open-end rotor spinning unit. The apparatus includes a spinning-in device for returning yarn end through a take-off duct into the spinning rotor, a severing device for shortening the yarn end to a predetermined length, and a withdrawing duct which communicates with the take-off duct and which is designed, on the one hand, for holding the yarn end by the action of a vacuum which, in the contact region of the two ducts, exceeds the working vacuum in the take-off duct, and, on the other hand, for withdrawing the severed yarn end. In accordance with an essential feature of the invention, at least one air nozzle opens into the withdrawing duct which during both spinning and spinning-in processes is connected to a subatmospheric pressure source, which nozzle is designed for introducing a fresh yarn end into the take-off duct by a controlled air outflow in a particular phase of the spinning-in process.

Abstract: An open end spinning machine includes a plurality of spinning units. Each spinning unit includes a first yarn breakage sensing device assuming a yarn sensing, operative position, in which it contacts the yarn, when the spinning unit is in a normal spinning operation and an inoperative position, in which it is not in contact with the yarn, when the spinning unit is in a transient condition either from or to the normal spinning operation, and a second yarn breakage sensing device assuming a yarn sensing position at least when the spinning unit is in the transient condition. Upon occurrence of yarn breakage when the spinning unit is in the transient condition, such breakage is detected by the second yarn breakage sensing device and the supply of fibers to the associated spinning unit is interrupted by the second yarn breakage sensing device.