Abstract: A method for piecing a thread formed in an open-end rotary spinning machine to an end of a previously formed thread, wherein spinning fibers are fed to at least one rotating fiber collection surface, the collected spinning fibers are further transported to a thread forming station connected to the fiber collection surface, and the end of the previously formed thread is joined to the spinning fibers transported to the thread forming station as the thread end is rotated, the pieced thread being continuously withdrawn from the thread forming station while spinning fibers are being continuously fed to the fiber collection surface includes a method for piecing a thread formed in an open-end rotary spinning machine to an end of a previously formed thread, wherein spinning fibers are fed to at least one rotating fiber collection surface of a spinning rotor disposed in a closed spinning chamber under negative pressure, the collected spinning fibers are further transported to a thread forming station connected to the

Abstract: A open-end spinning assembly includes a silver insertion device, a fiber separating device, a fiber guide device, a fiber collector for collecting, aligning and imparting a rotational movement onto fibers and subsequently applying the fibers to an open yarn end, and a draw-off device drawing-off yarn from the yarn collector. A fed-back yarn end is applied to a piecing fiber quantity fed into fiber collector for forming a piecer. The yarn is continuously drawn-off from the fiber collector and fibers and continuously fed into the fiber collector. A method for monitoring the piecers includes automatically measuring diameter values relative to the longitudinal axis of the yarn for the piecer and for yarn lengths upstream and downstream of the piecer having at least substantially the length of the piecer. The diameter values are electronically stored in memory and compared with comparison values for producing a comparison result.

Abstract: A process of automatic yarn spinning-in in the spinning unit of an open-end rotor spinning machine of an automatic service device provided with a control unit having a programmable microprocessor control system for controlling the spinning-in cycle and the automatic adjustment of spinning-in parameters modified according to successive verifying tests which are performed by the automatic service device which is either arranged in the individual spinning units, or as a unit traveling along the machine. By successive tests, spinning-in parameters are adjusted for an interval for yarn return to the spinning rotor as well as for determining the start of fiber feeding. The spinning-in parameters can be corrected by further verifying tests in spinning units with various dynamic characteristics.

Abstract: In order to piece to an open-end friction spinning device with two friction spinning elements driven in the same direction and forming a nip subjected to suction, fibers fed into such nip are twisted into a fiber bundle. The fiber bundle is partially conveyed out of the nip in a longitudinal direction, grasped there, and then transferred to a winding device. An auxiliary conveying device is provided to convey the fiber bundle from a thread forming zone adjacent the spinning element nip up to the draw-off side end of such friction spinning elements. A grabber is provided to grasp the fiber bundle as it leaves such nip of the friction spinning elements and to transfer the forming thread to a draw-off device.

Abstract: To piece up to a spinning station consisting of two friction spinning elements (101) driven in the same direction and forming a nip, a thread 30 is conveyed to the nip so that said thread 30 reaches the thread forming zone (104) with its free thread end first. Feeding of the fibers into the nip is controlled so that the thread end (300) comes into contact with the fibers simultaneously with its reaching the thread forming zone (104). The friction spinning elements (101) are covered by a cover (130) which incorporates a fiber feeding channel (24). The cover, in addition to the fiber feeding channel (24), is equipped with a thread insertion slit (14) extending essentially in the longitudinal direction of the friction spinning elements (101). The thread insertion slit (14) extends from the outside of the cover (130) up to its inside, and from the end on the draw-off side up to the outlet end (240) on the side away from the drawoff.

Abstract: An improved method and apparatus for stringing up or re-stringing a balanced ply-twisted combination yarn of two components to insure strong piecing-up points. The end of the combination yarn and the end of a continuous filament yarn, which becomes a component of the combination yarn, are both prepared for piecing and inserted into the rotor of an open-end spinning device. Upon start up, the combination yarn engages staple fibers in the rotor consolidating groove while the continuous filament yarn engages the combination yarn within the rotor without any contact of the continuous filament yarn with the rotor consolidating groove.

Abstract: An open-end friction spinning machine is provided having a plurality of spinning units arranged next to one another. A suction device assigned to each spinning unit which acts in the area of the yarn formation zone may be selectively switched off such as in the case of a yarn breakage. So that the air throughput balance does not change in the area of the other spinning units when the suction device of a single unit is switched off, devices are provided for maintaining the air throughput relatively constant. Air throughput normally used by the suction devices in the yarn forming area of the spinning unit is diverted, for cleaning and maintenance purposes.

Abstract: For piecing to an open-end friction spinning device with two friction spinning elements normally driven in the same direction of rotation and forming a nip therebetween, of which friction spinning elements at least one is capable of being subjected to suction, fibers are continuously fed to the nip and are then immediately removed from same. While fiber feeding continues uninterruptedly, the removal of fibers from such nip is then discontinued, so that fibers remain in the nip and form a rotating accumulation of fibers. A yarn end is then introduced to such accumulation of fibers. Newly formed yarn is then drawn off from the nip while fibers being fed continuously to such nip are continuously formed into such yarn. For such removal of fibers, a controllable suction air nozzle may be directed towards the above-mentioned nip from a side of the friction spinning elements opposite such nip.

Abstract: The invention provides for the spinning units of a multi-position rotor spinning machine to be driven by a common AC drive motor powered by a static inverter enabling the power supply frequency to the AC motor to be controlled for controlling the rate of acceleration and the operating speed and the rate of deceleration of the AC drive motor. This facilitates a method of mass stopping.

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: The invention provides for the spinning units of a multi-position open-end spinning machine to be driven by a common AC drive motor powered by a static inverter enabling the power supply frequency to the AC motor to be controlled for controlling the rate of acceleration and the operating speed and the rate of deceleration of the AC drive motor. This facilitates a method of mass start-up and mass stopping of a friction spinning machine are disclosed.

Abstract: In an open-end spinning machine, a centralized main drive is provided to collectively drive spinning elements of a plurality of spinning stations installed next to each other. At each spinning station, a switch-over device is provided for switching each spinning station over to a stationary, centralized auxiliary drive. The main drive includes a main drive belt to collectively drive the plurality of spinning elements. An auxiliary drive belt driven at a second speed for selectively driving individual spinning units is powered by the stationary centralized auxiliary drive. Using its respective switch-over device, either the main drive belt or the auxiliary drive belt can be selected to drive a given spinning unit. Thread joining preferably takes place at a spinning unit (e.g. spinning rotor) speed relatively close to the production speed of the spinning unit so that strong thread joins and consistent thread results.

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: The spinning or twisting machine comprises a plurality of drafting rolls, a plurality of associated spindles and positioned between them a plurality of yarn breaking devices pivotable between an upright spinning machine operating position into a yarn breaking position. According to our invention the yarn breaking device is movable by a positioning device from its yarn breaking position into an operating position.

Abstract: A process is provided for operating open-end friction spinning machines of the type including movable friction surface parts defining a yarn forming region and a suction device for creating a suction effect on the yarn forming region. The process includes reducing the suction effect when spinning operations are interrupted, and interrupting the suction device at a point no later than the return of a yarn end into the yarn forming region. An apparatus for performing the process is also provided.

Abstract: A device for removing residual fibers from perforated friction surfaces of an OE-friction spinning machine includes a suction device including a controllable cut-off element connected to a suction source, a suction tube section connected between the cut-off element and the friction surfaces, and a controllable compressed air connection disposed in the suction tube section.

Abstract: An automatic splicer for spun yarn, including open end spun yarn. Opposite yarn ends for splicing are inserted in opposed yarn clamping devices, adjacent yarn loop pulling devices, in a splicing slot of a splicing chamber, adjacent mechanical combing devices and in yarn severing devices. Excess yarn is cut from the yarn ends by the yarn severing devices at a predetermined distance from the splicing slot and the yarn loop pulling devices are advanced to pull the ends of the yarns to the combing devices at which air is applied to the yarn ends to direct the yarn ends to the combing devices. The yarn loop pulling devices are then partially retracted to feed the yarn ends into the combing devices at a controlled rate of feed for combing the yarn ends progressively from their ends to a length corresponding approximately to the length of the subsequent splice.

Abstract: A piecing process is provided for an open-end friction spinning apparatus of the type including movable friction surface members forming a yarn-forming zone therebetween. A friction surface driving device for moving the friction surface members during operation and for interrupting the movement of the friction surface members is also included in the apparatus. The spinning apparatus further includes a yarn end orientation member for orienting a yarn end during the piecing process. The process includes placing a yarn end into the yarn-forming zone when the rollers are stopped. The friction surface members are started such that the yarn end is prevented from being pulled too deeply into the yarn-forming zone by the yarn end orientation device. An apparatus for carrying out this process is also provided.

Abstract: A method of piecing yarn in the operation of an open end rotor spinning machine that includes applying the suction that picks up the yarn end from the bobbin package for an extended predetermined length of time longer than the optimal minimum length for a normal piecing operation, with the extended suction being of a time sufficient to remove an estimated extended length of defective yarn, either determined by sensing the absence of sliver or after two or three sequential unsuccessful piecing attempts.

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: A method of forming a thread joint in an open-end spinning machine having a sliver drawing-in device for drawing in a sliver and feeding it to a fiber loosening device from which it is guided by a fiber guiding device to a fiber accumulator at which the fibers are accumulated, disentangled, imparted with a rotary motion, and thereafter engaged with an open end of a thread, and a take-up device for drawing the thread out of the fiber accumulator includes for the purpose of joining a joint, bringing a thread end which is fed back into the fiber accumulator into contact with a quantity of fibers to be joined which have been previously fed into the fiber accumulator, continuously withdrawing the thread out of the fiber accumulator and continuously feeding fibers into the accumulator, continuously measuring the quality of the joints and automatically controlling, in accordance with the quality, the quantity of fibers being joined.

Abstract: The method for starting up a friction spinning assembly is used in a friction spinning assembly including: friction surfaces movable in opposite directions forming a spinning wedge, at least one of the friction surfaces being a perforated drum having a suction device with a suction nozzle acting on the spinning wedge by suctioning air through the wall of the at least one perforated drum; at least one suction device acting on the spinning wedge; and an automatic startup device performing a thread joining operation.

Abstract: The yarn reserve forming device is constructed and operated to release a yarn loop for uncontrolled movement from a deflected yarn path into a normal yarn path for return to the withdrawal tube of the spinning machine. The yarn reserve forming device includes a yarn retainer which can be pivoted to release the yarn loop for immediate return to the withdrawal tube.

Abstract: Each of the operating stations is provided with a locating element while the service tender carries a sensor for aligning the service tender with a selected operating stations. The sensor includes a rotatable member on which a pair of rollers is mounted and from which a leaf extends to cooperate with various photodetectors. With the sensor in an operative position, the rollers sequentially contact the locating element of a selected operating station and by pivoting cause the leaf to cooperate with the photodetectors to generate a sequence of signals. This sequence of signals is used to slow the service tender and to thereafter brake the service tender to a halt in alignment with the selected operating station.Should the service tender overrun the locating element, signals are also generated to reverse the direction of movement of the service tender in order to effect alignment.

Abstract: An automatic thread joining apparatus for an open end spinning machine includes a device for producing a tension-proof thread connection forming a thread joint, a device for removing the thread joint, a controllable thread storage device for intermediate storage of a length of thread spun during operation of the device for producing a tension-proof thread connection, and a thread removal device associated with the thread storage device being activated upon the occurrence of an unsuccessful thread connecting operation.

Abstract: The starting or re-piecing of a yarn in an open end spinning machine is accomplished during full speed rotation of the spinning unit. A travelling piecer provides a fixed length of yarn to be back-fed into the spinning unit. A control which is responsive to the speed of rotation of the spinning unit causes the nip rolls to close together in order to deliver the new yarn from the spinning unit at the operating speed of the spinning unit.

Abstract: Each of the spinning stations is provided with a profile locating element or marker as well as a signal lamp for indicating a disturbance in a spinning unit. The service tender carries a locating device which includes a spring biased body which is capable of moving perpendicularly to the direction of movement of the service tender towards a spinning unit to which the service tender has been called. The body carries a pair of rollers which are mounted on a pivotable turntable so as to be pivoted when passing over a locating element of a spinning station.The locating device serves to generate signals for braking the service tender to a halt in alignment with a selected spinning station.The service tender also carries an anchoring system which uses a plate coated with a layer of friction material for engaging a rail on which the service tender moves for securing the tender in an aligned position with a spinning station.

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 order to start or recommence spinning of a yarn in a friction spinning device, the following method steps are carried out upon start-up of a new spinning operation or upon piecing after a thread break: fibers separated by an opening device are delivered by means of a fiber transporting passage to a rotating friction spinning drum and are twisted to form a twisted fiber structure; when the twisted fiber structure has substantially reached a predeterminate diameter or size, then the twisted fiber structure is transported by an airstream delivered by a pressure duct towards and into a guide tube and is forwarded therein into a convergent space of rotating withdrawal rolls; and the twisted fiber structure is caught at production speed by these withdrawal rolls and delivered on a divergent side of the withdrawal rolls to a receiving suction device which transfers the spun yarn subsequent to the twisted fiber structure to further processing elements.

Abstract: In a friction-spinning process, the fibers (30) are twisted together on a thread formation line (43) as a result of the rotation of two friction elements (1, 10) driven in the same direction and forming a V-shaped nip and are drawn off as a thread (4). For piecing, the thread (4) is returned into the piecing position outside this thread formation line (43) and only then is placed in the thread formation line (43). During the run-off of the thread (4) from the friction elements (10), the pressing force of the thread (4) against at least one of the friction elements (10) is increased. For this purpose, a thread guide element (5) is arranged directly after the friction elements (10) and is movable transversely relative to the thread draw-off direction (42).

Abstract: An apparatus for open-end friction spinning is provided with at least one suction roller connected to a suction device. The suction device is connected via a valve with an underpressure or vacuum source which permits the adjustment and the switching off of the suction effect of the suction device. Adjusting elements operating independently of each other are respectively provided for switching off of the suction effect and for controlling the amount of the suction effect. These adjusting elements are operable by a moveable servicing apparatus.

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: An open-end friction spinning machine is provided having a plurality of adjacently arranged spinning units and a movable start-spinning device capable of attachment to a spinning unit requiring service. The broken yarn end for the start-spinning process is returned into the spinning unit against the normal yarn withdrawal direction. In order to safely accomplish the return of the yarn into the area of the friction spinning region which is preferably formed by two adjacently arranged rollers forming a wedge-shaped gap therebetween, a compressed air jet is provided which returns the yarn end through the friction spinning zone.

Abstract: A device for untwisting the end of a yarn in a pneumatic yarn splicing apparatus comprising a yarn end untwisting nozzle pipe for jetting a compressed air in the direction toward the axis of the pipe so as to cause the yarn end to be untwisted, in which the point at which the yarn is inserted in the opening of the pipe can be determined by a positioning member mounted adjacent the opening.

Abstract: A method for starting the spinning of a thread in an OE-spinning device includes exposing a thread end to a gas current before starting spinning, subsequently conducting the thread end to a spinning element, collecting spinning fibers at the spinning element, and subsequently applying the spinning fibers to the thread end, and an apparatus for carrying out the method.

Abstract: A method for determining yarn number and thickness deviations for yarn connecting processes in automatic open-end spinning machines includes producing a yarn connection at a yarn connection point, subsequently automatically measuring one of the yarn number, yarn thickness and yarn mass per unit length in a yarn section of limited length upstream of the yarn connection point with the yarn running to produce a measured value, comparing the measured value with a comparison value, and inducing a signal with an indication regarding the spinning unit in the case of a deviation between the measured and comparison values with a predetermined magnitude, and an apparatus for carrying out the method.

Abstract: A friction spinning apparatus includes a yarn winder and a pair of friction spinning rollers of which one is perforated and provided with a suction slot which is opened and closed on rotation of a piecing lever, means being provided for interconnecting operation of the piecing lever with, on the one hand, restoration of the winding operation and, on the other hand, restoration of fibre feed to the nip between the two friction spinning rollers.Preferably the interconnecting means comprise a pair of cams on the drive shaft linked to the piecing lever and co-operable with respective switches to control drive to the fibre feed roller of the fibre-opening unit and also the package lift mechansim to initiate winding.

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: Each of the operating stations is provided with a signal directing means for emitting a call signal indicating a need for servicing, a positional reference marker in order to initiate a braking operation and a locating reference marker for exactly locating a service tender relative to the operating station.The service tender carries a signal receiving means for receiving a call signal emitted for an operating station during passage by the operating station. In addition, the service tender includes a sensor which is responsive to the positional reference marker of the operating station to be serviced which serves to initiate braking of the motor for the service tender. Further, the service tender carries a locating device which cooperates with the locating reference marker of the operating station in order to locate the tender relative to the operating station for servicing purposes.

Abstract: To improve the re-piecing operation, especially in terms of its success rate, at high spinning speeds, the free thread end cut to the length of a piecable end and retained after cutting the length is exposed to a turbulent air flow which causes it to execute whiplash-like oscillations. The surface of the thread end is thereby roughened. The thread end prepared in this way is subsequently transferred to the fiber-collecting surface of the open-end spinning apparatus. The roughening of the surface of the free thread end is accelerated when the end is whipped against an edge-like projection or a rough surface.

Abstract: The travelling piecer is constructed to accomodate piecing of a thread which is broken during winding onto a thread package or to accomodate starting of a fresh package on a bobbin. The piecer includes a suction nozzle to find a broken yarn end from a package, a centering mechanism for positioning the located yarn in a predetermined position and a threading device for forming the located yarn into a loop.A carrier for an auxiliary yarn package is also provided with a roller pair for feeding a yarn from a package and a second suction nozzle for manipulating the auxiliary yarn into a predetermined position extending from the first nozzle for interception by the centering mechanism.

Abstract: A process is provided for connecting the end of a new fiber band to the end of a fiber band running into an open-end spinning arrangement wherein the threading on is conducted in such a manner that the joining point between the new fiber band and the fiber band already running into the spinning arrangement does not result into a change in the yarn number. In one embodiment it is provided that the fiber bands are prepared in such a manner and connected to each other, especially by means of twisting them together, such that a joining point exhibits at least approximately the same number as the other areas of the fiber band. In a second embodiment, it is provided that following a joining of the two fiber bands the feeding device of the spinning arrangement is switched on until the joining point is running into the spinning arrangement whereby the fibers fed during this time period are transported off within the spinning arrangement.

Abstract: To piece up a yarn in a friction spinning device, fibers supplied to a yarn formation position of a friction spinning drum are twisted to form a twisted fiber structure until the latter has sufficient strength for grasping by a suction device moved towards the twisted fiber structure end opposite to yarn withdrawal. The suction device grasps this end and stops such twisted fiber structure. Further fibers wound about the now substantially stationary twisted fiber structure strengthen the so it can be withdrawn by the suction device. Due to such withdrawal and constant further supply of fibers, a yarn-like structure is formed adjoining the twisted fiber structure and such yarn-like structure is also withdrawn. To subsequently again form the actual yarn, withdrawal rollers are engaged so the yarn produced at the yarn formation position is withdrawn at production speed or with a reduced speed still sufficient for forming a yarn.

Abstract: When a thread is joined in an open-end spinning device, the thread is fed back into the open-end spinning device as a result of reverse rotation of a bobbin and a pair of auxiliary rollers. After the feedback has ended, the thread is released by the pair of auxiliary rollers and, until normal spinning draw-off is started, the thread is subjected to an auxiliary draw-off at a greater distance from the open-end spinning device than the normal spinning draw-off. This auxiliary draw-off can be carried out exclusively by means of the bobbin or also independently of it. An auxiliary draw-off device serves for generating this drawing force and is located at a greater distance from the open-end spinning device than the pair of draw-off rollers.

Abstract: Each of the spinning stations is provided with a cradle having a pair of arms which are pivotally mounted on a carrier. The service tender is provided with a pair of light beam emitter/receiver units so that when the tender is called to and aligned with a specific spinning station one emitter/receiver unit is able to detect the presence of the carrier in a raised position while the second emitter/receiver unit is able to detect the presence or absence of a yarn package or bobbin tube on the cradle.The service tender is operable in response to the combination of signals received from a calling station at the spinning station and the signals received from the emitter/receiver units.

Abstract: To stop and restart and open-end spinning machine with a plurality of spinning devices, all the spinning devices are stopped together, while the vacuum is maintained. The thread end resulting from this interruption in the spinning process is then prepared successively at each spinning unit for joining and is fed to the spinning device in a thread-joining position, whereupon the vacuum is then cut off. When the open-end spinning machine is started, after the vacuum has first been applied, the threads are fed together, on all the spinning devices to the fiber-collecting surfaces of the spinning devices. The open-end spinning machine has a service device movable along the machine for preparing the threads to be joined and for feeding them to the individual spinning cells, as well as a central control device which has a stoppig device and a starting device for the open-end spinning machine. The stopping device is connected in control terms to a switch-on device and to a switch-off device for the service device.

Abstract: A thread-reserve winding is formed on a bobbin tube of a spinning machine in which the thread is drawn off continuously from the spinning machine by means of a pair of draw-off rollers and, to form the thread-reserve winding, is grasped and wound onto the bobbin tube. According to the invention, immediately after the thread has been grasped, the spinning tension is put into effect to wind on the thread-reserve winding and, after the thread-reserve winding has been applied, the thread is wound on under the normal winding-on tension. In this way, the thread is drawn off by the bobbin tube under a thread tension sufficient to ensure a taut winding.

Abstract: A process for rejoining the thread on an open-end friction-spinning device, in which fibers are fed into a V-shaped nip subjected to suction, and the thread formed in the V-shaped nip is drawn off from this and wound onto a bobbin. For rejoining, the fiber feed into the V-shaped nip is interrupted and a thread end drawn off from the bobbin is guided towards the V-shaped nip counter to the spinning direction. This thread end is paid out in front of the V-shaped nip and is stored in a joinable length in a storage station at the end of the V-shaped nip facing away from the bobbin. The bobbin is then advanced towards its drive roller and the thread is drawn off from the storage station. After a predetermined time after the start of the thread draw-off, the fibers are fed again into the V-shaped nip, where they come up against the thread end running through the V-shaped nip and are twisted together with this.

Abstract: To the purpose of obtaining the joining of textile threads, by means of a splice accomplished with compressed gas, by a short, strong joint of nearly imperceptible appearance, a method is proposed, which includes the following steps: inserting the two threads to be joined through a longitudinal slit in a splicing chamber provided in a head having two parallel opposite side walls perpendicular to the longitudinal axis of the chamber, in correspondence of which walls there are side outlets; substantially closing the side outlets of the chamber and at the same time locking the threads entering the chamber through its related side outlets, against the respective side walls of the head, but leaving free and unlocked the cut tails of the thread coming out of the outlets; and subjecting the thread lengths enclosed within the chamber to at least one burst of compressed gas blown into the chamber, the gas escaping through a port provided in the head transversely to the longitudinal axis of the chamber.