Abstract: The yarn formation area of a friction spinning apparatus, in which the rotating friction rollers and the feed duct lie closely adjacent, is quickly and simply cleaned of remaining fibres at a yarn break and protection is provided against damage caused by excess fibres entering the area. One of the rollers, which is imperforate, is mounted for pivotal movement away from the area and at a break suction through the other roller is temporarily closed off from one end of the area toward the opposite end to eject the remaining fibres. Return movement of the roller is guided to ensure proper return to the operating position.

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: Spinning is started on a friction spinning apparatus by drawing the end of yarn back to a position adjacent the surface but in such a condition that it is free from the influence of the suction through the surface. This is done by closing off the suction while the end is in the position so that the yarn is drawn by an additional suction source into an adjacent position. The yarn end is drawn from one end of the surface to lie along the surface by gradually closing off the suction from that end toward the opposite end. Subsequently the suction is reopened to bring the yarn end under its influence to draw the end onto the surface so the fibre feed and take-up can be restarted.

Abstract: The invention relates to winding a yarn on a package. A package tray is provided which in an operative position retains the package out of contact with a package driving roller against the effect of a restoring force tending to move the package into driving contact with the driving roller. Retraction of the tray to an inoperative position so as to enable the package to be brought into contact with the driving roller is effected by reducing the restoring force.Preferably, the invention includes open-end spinning means for producing the yarn and retraction of the tray to the inoperative position takes place during a yarn piecing-up procedure.

Abstract: The method and apparatus for removing irregularities in a thread being produced on a machine as the thread is traveling to a takeup device. A thread reserve having a suction applied thereto causing a loop to be formed therein which contains said irregularity. An additional pair of loops are formed in said thread, one above and one below the thread reserve. The loop formed in the end of the thread reserve is severed from the thread and the two remaining loops are inserted into a thread joining device. A thread suction extractor associated with the thread joining device pulls the end portions of the pair of loops taut permitting the joining operation to take place and, after joining of the thread, removing the separated ends.The thread reserve is provided with mechanism for maintaining the loop of thread extending therein separated and for severing and removing the portion of the loop containing the irregularity from the thread.

Abstract: A pair of draw-off rollers (10, 11) of a thread drawing-off device comprising an over-mounted pressure roller (11) which cooperates resiliently with a driven roller (10) which projects across the front of the pressure roller (11). The pressure roller (11) has at least one recess (113, 114) on its front face (110) which is dimensioned in such a way that it temporarily completely releases a thread (4) sliding along the surface of the driven roller (10) and lying adjacent to the front (110) of the pressure roller (11). By means of a device of this type, the thread (4) is drawn off, for the purposes of joining, to such an extent from the spool (31) that the thread (4) reaches the side (310) of the spool (31) which is facing away from the front (110) of the pressure roller (11) provided with recesses (113, 114). The thread is then introduced into the spinning chamber (2) and is joined.

Abstract: The machine has a framework (1) with a rotation drive, spinning stations, a yarn withdrawal unit (2) and yarn winding devices (3) disposed thereon. Each spinning station comprises a fibres feed unit (4) and a spinning chamber (5), having a housing (14) installed on the framework (1) so that it can be withdrawn from the fibres feed unit (4). The yarn withdrawal unit (2) comprises a driving shaft (22) mounted on the framework (1), and pressing rollers (23), which in operating position are resiliently pressed to the driving shaft (22) and can be withdrawn from said driving shaft. Each yarn winding device (3) is mounted at a respective spinning station and comprises a bobbin carrier (27) and a yarn spreader (28). According to the invention each pressing roller (23) is mounted on the housing (14) of the respective spinning chamber (5), and each yarn winding device (3) has operative connection (31) with the housing (14) of a respective spinning chamber (5) to disengage and engage the rotation drive.

Abstract: When an open end spinning machine is stopped, a fiber supply to a spinning rotor is first stopped and thereafter, substantially simultaneously with stoppage of both a yarn take-up roller and a yarn winding roller, a yarn end is held by a yarn holding device at a time when it still remains in a region which undergoes the suction effect of a subatmospheric pressure produced in the spinning rotor. The spinning rotor is subsequently stopped. On starting, the holding of the yarn end by the yarn holding device continues even after restarting of the spinning machine until the subatmospheric pressure produced in the spinning rotor reaches substantially the same value as that produced during a normal spinning operation. Therefore, there is prevented any snarling phenomenon, resulting in a greatly increased success rate in the operation of connecting yarn ends on re-starting of the spinning machine.

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.

Abstract: Method of and apparatus for operating an open end spinning machine having a plurality of spinning units each including a sliver feeding device, a fiber separating device, a twist forming element, a yarn taking-off device, yarn winding device and a reversing mechanism for returning the yarn end back into the twist forming element. The twist forming element and the fiber separating device are set in operation; thereafter the fiber feeding is started simultaneously with the yarn end reverse travel to return same into the twist forming element in which a fibrous ribbon is formed of the fibers supplied. After spinning-in said yarn end with said fibrous ribbon the yarn is again set into a forward operative travel.

Abstract: Method and apparatus for joining a thread returned by a traveling joining device from a take-up coil to a spinner rotor of an open-end rotor spinning machine station, including a thread joining device being disposed on the joining device and being shiftable into reverse motion for returning the thread to the spinner rotor, a thread pulling device disposed on the joining device, a thread support disposed on the spinning station, a device for transferring thread after joining from the thread pulling device to the thread support, and a thread accumulator insertable into the path of the thread between the thread pulling device and the take-up coil.

Abstract: A device comprising a casing which bears two distinct hinged (articulated) systems, of which one is activated by jacks and includes four arms of which two are hinged together at one of their ends while another is hinged on the casing and on the free end of the arm, and the arm is hinged on the casing and at the middle of the arm that bears a roller to disengage the cop from the drive shaft.The other system comprises two parallel arms hinged on an intermediate plate, two parallel arms hinged on the plate and on a support of the re-attachment head connected to a system of suction by means of a conduit and including two motors to drive in rotation a roller controlling the cop and to make its front part rotate by 180.degree. in respect of its rear part.In the re-attachment position the roller is employed to rotate a roller by friction located at the outlet of the turbine.

Abstract: According to this invention, a spinning rotor is increased in speed until it reaches a predetermined higher speed beyond a lower speed region and then decreased in speed until it falls within the lower speed region, in which a yarn ending is effected. Thereafter, the speed of the spinning rotor is increased to a normal spinning speed beyond the predetermined higher speed. During rotation of the spinning rotor at the predetermined higher speed, sufficient subatmospheric pressure is produced in the spinning rotor to stretch out the yarn end thereby to prevent the yarn end from being snarled. Also, during this higher speed rotation of the spinning rotor, sufficient fibers in the spinning rotor can be collected in a maximum diameter portion in the spinning rotor to be connected with the snarl-free yarn end in a favorable condition.

Abstract: A joining device for joining a thread returned from a take-up coil to a spinning rotor of a rotor spinning machine by a thread regulator, the thread regulator having a thread clamp includes a roller pair, at least one of the rollers of the roller pair being drivable in direction in which the thread is returned.

Abstract: To start-spin a thread with open-end spinning, the end of the thread is inserted into a spinning rotor against the normal direction of draw, placed on a ring there formed of fed fibres and drawn off again. The end of the thread is placed on the ring at a start-spinning speed which is lower than the operating speed of the spinning rotor. In order to avoid undesired changes in the thickness and strength, etc. of the thread at the start-spinning point, the feed of the sliver, which determines the thickness of the ring of fibres located in the spinning rotor, is reduced in a ratio to the normal operating condition which at least approximates the ratio between the start-spinning speed of the spinning rotor and its operating speed.

Abstract: The servicing apparatus is mounted for running movement along, and for pivotal movement laterally of, a path of travel having a first section extending adjacent spinning units of the spinning machine and a second section extending adjacent an end cabinet of the spinning machine. During movement of the apparatus from the first and to the second section of its path of travel, it is pivoted laterally of such path to provide clearance between interfering components of the apparatus and the cabinet of the machine that would otherwise preclude movement of the apparatus along the second section of its path of travel. Pivotal movement of the apparatus is realized by a cam means so located as to not impede traffic adjacent the machine or access to the interior of its end cabinet, and as to minimize the magnitude of the force required to produce the aforesaid pivotal movement.

Abstract: A method and apparatus for servicing a number of mutually adjacent spinning positions of an open-end spinning machine by means of a servicing apparatus which can move along the spinning positions. A travel drive is provided for the servicing apparatus for driving the servicing apparatus along the spinning machine when activated. Switches are connected to the travel drive for activating the travel drive responsive to being activated by an operator at a spinning station requiring service. A switch is also provided for de-activating the travel drive for halting the movement of the service apparatus in the neighborhood of the operator at the spinning station requiring service.

Abstract: A method and apparatus for individually piecing up yarn on an open-end spinning machine which has a spinning rotor and a rotor brake. A rotor cleaning apparatus is carried on a pivotal cover and is used for cleaning the rotor responsive to being activated. A pivotal lever which when moved relative to the cover simultaneously activates the rotor cleaning apparatus and the rotor brake causing the rotor to be cleaned as the rotor is being stopped. The yarn is pieced up when the rotor is being brought back up to running speed.

Abstract: A centralized control system for open end spinning machines comprises a group control unit essentially consisting of a first spinning control means composed of a plurality of sequentially operated logical elements connected in series, the first spinning control means producing from the respective logical elements parallel outputs each of which is fed to a plurality of spinning units so as to control the spinning operation thereof, and an individual control unit essentially consisting of a second spinning control means each of which constituent is the same as the first spinning control means. A spinning mechanism includes a yarn breakage sensor provided in the stream of spun yarn, a driving means for driving the spinning mechanism including a plurality of driving motors, controlled by the output from the group or individual control unit.

Abstract: During servicing of a spinning machine station by the piecing apparatus, the yarn positioning means establishes a generally U-shaped yarn line and brings the lowermost bight section of such line into desired association with the yarn delivery rolls at the spinning machine station. Rotatable members form the bight section of the yarn line and then transport the same, while the members occupy rotative positions effective to prevent lateral movement of the bight section, to a location closely adjacent the delivery rolls. The members then are rotated to other positions wherein they permit and guide lateral movement of the bight section toward a free end of one of the delivery rolls. When a piecing-aid device is present at the spinning machine station, the piecing apparatus includes a mechanism for imparting movement to a movable component of the device, and the positioning means of the apparatus includes means for associating parts of the U-shaped yarn line with the foregoing and other components of the device.

Abstract: A method of and an apparatus for piecing yarn in open end rotor spinning units. The returning of the yarn end into the spinning rotor for piecing is performed in two stages, in the first of which the yarn is stopped immediately upon breakage within the sucking range of the spinning rotor, and is brought immediately thereafter into a withdrawal chamber in which the yarn end is retained. In the second stage the yarn end is separated and deposited in said withdrawal chamber, and the new yarn end is introduced by further reverse motion into the spinning rotor. The apparatus has a withdrawal chamber interposed between the inlet of the withdrawing channel and a cutting mechanism. In one embodiment said chamber is connected to the withdrawing channel, opposite which there is mounted a nozzle connected to a controlled pressure air source. In another embodiment there is provided a nozzle communicating with the withdrawal chamber, said nozzle being connected to a controlled source of underpressure.

Abstract: A knotting mechanism for use on open-end spinning machines for performing a knotting process on yarn produced on machines. The knotting mechanism is mounted so that it can be moved longitudinally along the spinning machine and transversely to the spinning machine to a knotting position. A switch-on mechanism is activated responsive to the knotting mechanism being moved transversely to the spinning machine to a knotting position. A driving mechanism is provided for initiating the knotting process on the yarn upon being activated. A release mechanism is operably connected to the driving mechanism for activating the driving mechanism responsive to the switch-on mechanism being activated. A timing device de-activates the driving mechanism after a predetermined period of time sufficient to carry out the knotting process and prevents the driving mechanism from initiating another knotting process without the switch-on mechanism being further de-activated and re-activated.

Abstract: In a controlled stopping procedure for an open-end spinning machine the fibre feed roller and the yarn delivery rollers decelerate in synchronism. A detector senses a predetermined speed of the yarn delivery rollers after a period of time from starting the deceleration and initiates the stopping of the fibre feed roller. After a further period of time, determined by time delay means, the decelerating yarn delivery rollers are braked. Preferably the yarn delivery rollers have come almost to rest when they are braked.

Abstract: A method and apparatus for the elimination of an irregularity in a yarn being produced on an open end spinning machine and drawn off therefrom by a pair of draw-off rollers and wound on a bobbin. The yarn is deflected into an N-shaped run so that a knotting mechanism can knot the parallel portion of the yarn together so as to remove the irregularity in the yarn. Yarn guides are provided on the knotting mechanism for displacing an oblique portion of the yarn out of the knotting mechanism when in use.

Abstract: An elongated suction air nozzle provided for forming a thread reserve in the form of a loop in thread running past the mouth thereof. A constriction is provided in the nozzle and extends for the whole length of the expected loop size. The constriction divides the cross-sectional area of the nozzle into two partial areas resulting in air flow in the central region of the nozzle being of a greater velocity than in the two partial remote areas.

Abstract: Device for temporarily stopping the operation of spinning stations of a spinning machine equipped with means for automatic inspection and/or cleaning of the machine after an interruption in the spinning operation at a spinning station and for thereafter restarting the operation of the respective spinning station includes a monitoring device associated with each spinning station having means for producing an intentional interruption of the spinning operation at the respective spinning station when a given value of a characteristic of the uninterrupted spinning process is reached or exceeded and only when no other spinning station serviced by the means for automatic inspection and/or cleaning of the machine is out of operation due to an interruption of the spinning operation performed thereat that requires correction.

Abstract: An open-end spinning machine is provided which includes a plurality of commonly driven spinning units arranged in side-by-side relationship. Each of the spinning units includes a spinning rotor, an opening device for opening fibers, a fiber feed device for feeding fibers from the opening device to the spinning rotor, and vacuum producing means for generating an air current to act on the fibers to aid in the feeding through the fiber feed device. To accommodate start-up operations and restarting in the event of a shut-down spinning unit, piecing apparatus is provided which includes a thread end return device for returning a thread end into the rotor for piecing onto a fiber ring deposited inside of the rotor and for taking off the pieced thread. In preferred embodiments, the piecing apparatus is equipped with additional devices for controlling the rotor speed and the quantity of fibers fed during the piecing step.

Abstract: The invention relates to apparatus for piecing-up yarn on an open-end spinning machine.A yarn reserve forming member is movable between an extended position, in which it constrains the yarn to follow a prescribed reserve yarn path, and a retracted position, in which the yarn follows another prescribed and shortened path and the end of yarn and its length, which is the difference between the lengths of said prescribed paths, is permitted to return to the spinning means to contact fibres fed thereto.To achieve efficient piecing-up, the yarn moves between such prescribed pathways from one to the other under control of the reserve forming member while the reserve yarn path is in a sense depleted and the yarn is caused by yarn insertion means to be inserted in the delivery roller nip at a predetermined position in the course of movement by the reserve forming member when the latter moves to the retracted position.

Abstract: Servicing apparatus, such as rotor cleaning and yarn piecing apparatus, for servicing individual spinning assemblies of an open end spinning machine is provided. Operational disturbance responsive control equipment is provided for controlling the movement of the servicing apparatus to servicing positions at respective spinning assemblies where operational disturbances are detected. Step-by-step control equipment is also provided to control the servicing apparatus for sequential preventive maintenance servicing operations at the various spinning assemblies. In order to optimize preventive maintenance and disturbance response maintenance, a switch-over switch is provided for switching between the disturbance responsive control equipment and the step-by-step control equipment.

Abstract: Spinning machine apparatus is provided which includes a plurality of open-end spinning units, each of said spinning units being provided with a bobbin holder for holding bobbins to wind up the thread produced at the spinning unit. A supply station is fixedly disposed at each spinning unit for storing a supply of empty spool tubes provided with starter threads. A traveling servicing device is guided on tracks adjacent the spinning units and includes lever mechanisms for effecting removal of a full bobbin and replacement thereof with one of the supply of empty spool tubes at the respective supply station. According to preferred embodiments, the method of utilizing the apparatus includes manually filling the supply stations at the spinning units, with the traveling servicing device being automatically operated to effect the tube transfer operation.

Abstract: A method and apparatus for yarn piecing on an open-end spinning machine is provided which includes a plurality of predetermined working programs for carrying out the piecing steps. To accommodate automated provision of quality pieced places in the yarn being spun, a yarn monitoring device is provided for detecting the quality of the piece place in the yarn, which device generates a signal controlling the selecting of one of the predetermined working programs for the next piecing operation at the spinning assembly. In particularly preferred embodiments, a storage device is provided for storing information as to the particular working program utilized during the last successful piecing operation at the respective spinning assemblies, with retrievability of this stored data to select the same successful piecing program for the subsequent piecing operation at such spinning assembly.

Abstract: A mobile piecing device is providing for an open-end spinning machine of the type which has a plurality of separate spinning assemblies each having a rotatable storage spool for storing yarn as it is spun. Preferred embodiments of the invention include an auxiliary spool driving wheel for driving the storage spool during piecing operations, as well as a pair of feeding rollers for feeding the yarn to the spinning rotor and back to the spool. In order to prevent/reduce the formation of a loop and kinking of the yarn during the acceleration phase after the initial piecing, due to the different inertia movements of the spool and the thread and feed rollers, preferred embodiments of the invention include supplemental control mechanisms for controlling the course of the yarn between the feed rollers and the spool. In certain preferred embodiments, the driving mechanism for the spool is adjusted to assure corresponding rapid acceleration of the greater inertia spool as for the feed rollers and returning thread.

Abstract: Open-end spinning machine apparatus is provided which includes a plurality of open-end spinning assemblies disposed adjacent one another and a mobile servicing device for selectively performing servicing operations at respective ones of the spinning assemblies. To accommodate precise alignment of servicing instruments of the mobile servicing device with the part or parts being operated on at the individual spinning assemblies, aligning elements are provided at and carried by the servicing instrument, which aligning elements are precisely positioned with respect to the respective servicing instruments, and are engageable with guide elements at the respective spinning assemblies to precisely locate the servicing instrument with respect to the parts being operated on.

Abstract: A process and apparatus for piecing a yarn on spinning assemblies of an open end spinning machine is provided. A prepared yarn end is pieced to a sliver ring produced in a spinning rotor during running up of the spinning rotor from a predetermined slower speed toward its operational normal spinning speed. In order to accommodate application of the yarn end to the sliver ring, the formation of the sliver ring, and the drawing off of new yarn pieced together at the sliver ring, the invention provides for a control of the acceleration behavior of the spinning rotor so as to lengthen the time segment in which the piecing steps can be performed. In preferred embodiments, non-contact electromagnet or electrical eddy current braking means are provided for countering the driving torque of a common drive means for the rotors of several spinning assemblies, whereby the acceleration curve is flattened with a lengthening of the time period for existent desirable piecing speeds.

Abstract: A winding apparatus including a winding roll driving a bobbin and a yarn reservoir arranged between a yarn supply point and the winding roll. The state of filling of the reservoir is monitored by a monitoring device which generates a signal for controlling the speed of the winding roll. Interposed between a driven drive shaft and the winding roll are a pair of intermediate wheels which are selectively brought into engagement with the drive shaft and the winding roll responsive to predetermined states of filling of yarn on the reservoir that is sensed by the monitoring device so as to either drive the winding roll at speed higher or lower than the delivery speed at the yarn delivery point. A brake lever is operably connected to a mechanism which supports the intermediate wheels and is brought into contact with the winding roll when both the intermediate wheels are out of engagement with the shaft and winding roll for stopping the winding roll.

Abstract: An apparatus for controlling the driving of an open-end spinning machine whereby driving members such as feed roller, winding roller and draw-off roller are operated at timings optimum for spinning conditions at the time of starting or stopping the machine. Optimum conditions are determined by the amount of yarn wound on a yarn take-up roll of the apparatus.

Abstract: The present invention relates to a method and an apparatus for changing the ratio of the yarn taking-up speed to the number of revolutions of the rotor at the time of yarn piecing and normal spinning. According to the present invention, the ratio of the yarn taking-out speed to the number of revolutions of the rotor at the time of yarn piecing has a different value from that employed at the normal spinning, while the ratio of the yarn taking-out speed to the sliver supply speed is made constant at the time of yarn piecing as at the normal spinning, in a manner such that the spun yarn has fewer number of twists at the normal spinning than that at the time of yarn piecing. The rotor speed may also be simultaneously reduced as the speeds of the take-out and sliver supply are reduced.

Abstract: In a spinning frame the fiber feed device for each spinning unit is controlled by a separate clutch interposed between a common drive and each unit. The clutches are disengaged during initial start-up and the yarn ends from a previous operation are returned into the spinning chamber. The clutches are then engaged to feed fibers and the yarns are drawn out and taken up on a spool. A breakage detector is provided for each yarn which controls the clutch for each respective fiber feed.

Abstract: The yarn-piecing and cleaning system comprises an auxiliary carriage which is separate and distinct from the robot carriage but travels on the same track as this latter, is connected thereto by means of at least one compressed-air duct and contains a compressed-air generating set. Thus the design function of the auxiliary carriage is to supply air directly at the necessary pressure and also serves as a spinning waste reservoir while the robot carriage performs yarn-piecing and cleaning operations as a transfer and control unit.

Abstract: Device for monitoring the feeding of a fiber sliver in a spinning machine having a device for feeding the fiber sliver thereto and a device for loosening the fibers of the sliver prior to spinning the fibers into a thread includes a device for detecting the presence and absence of the fiber sliver at a location forward of the fiber-loosening device along a path of travel of the fiber sliver from the device for feeding the fiber sliver to the device for loosening the fibers of the sliver, the fiber-loosening device having an inlet for the fiber sliver being fed thereto, and the sliver detecting device being located a distance at least equal to a staple length of the fibers of the sliver from the inlet of the fiber-loosening device.

Abstract: A thread-tying device for a spinning frame has a yarn locating head which locates the broken end of the yarn on the spool and is connected by a transmission which transmits the movement of the drive shaft to the disengaged spool. The broken end of the yarn is recovered and retained while the transfer mechanism conveys the yarn into the proximity of the turbine outlet. The mechanism has guide means determining the trajectory of the head between a position in which the transmission member is simultaneously adjacent the spool and the drive shaft, and the position in which the yarn retained on the head is carried substantially to the level of the turbine outlet.

Abstract: Method of controlling thread joining in a rotor-spinning machine, which includes applying a pulse proportional to the rotary speed of the spinning machine rotor to control a measure of the material being processed in the spinning operation, and device for performing the foregoing method.

Abstract: A device for retransporting a thread end of a take-up coil to a withdrawal tube of a spinning machine, includes a two-armed suction tube with a suction nozzle, the suction tube being pivotally mounted and being formed with a bend in a plane wherein it is pivotable, the suction tube having a longitudinally extending slot formed on the inside of the bend for passage of a thread therethrough and into the suction tube under suction, the suction tube having a suction-air flow path extending from the suction nozzle at an end of one of the suction-tube arms through the one suction-tube arm and through the other of the suction-tube arms to the end of the other suction-tube arm and therefrom through an air guidance part to a union for a negative-pressure suction source.

Abstract: A yarn ending unit, applied to an open-end spinning machine, which performs ending by means of the ending unit running in front of said spinning machine. The ending unit includes a friction roller for driving a package unit and a friction roller for driving a feed roller, both fitted to said ending unit. The two friction on rollers are driven by a variable speed electric motor, the number of revolutions of which can be controlled in response to the number of revolutions of a rotor fitted to said spinning machine. A hook is provided for each spinning machine, to hold one end of a yarn, and said hook is designed to be operable by a solenoid, energized by output from the control means.

Abstract: Bobbin exchange apparatus is provided for open-end spinning machines of the type having a plurality of spinning assemblies provided with respect to bobbin holders for holding bobbins to store thread. A depot device in the form of axially movable spring clamping jaws carried by a carrier rod extending along the length of the spinning machine is provided at each spinning assembly. To effect the ejection of a full bobbin from the bobbin holders and the insertion of an empty tube from the associated depot device, a mobile servicing device is provided which includes an empty tube engaging means for clampingly engaging an empty tube in the depot device and transferring the same to the bobbin holder with movement in a single plane.

Abstract: Servicing apparatus is provided for servicing a multiplicity of spinning assemblies arranged side by side in open end spinning frame. The apparatus includes a plurality of part instruments for performing separate servicing operations at respective ones of the spinning assemblies, such as part instruments for cleaning, piecing up operations, and spindle bobbin exchanges. Since these part instruments are geometrically wider in the travel direction thereof than are the individual spinning assemblies, the invention involves a geometric arrangement of the various parts within the part instrument so as to accommodate simultaneous servicing of adjacent spinning assemblies by two different part instruments, without the part instruments blocking one another.

Abstract: Open-end spinning machine apparatus is provided which includes a yarn measuring device at each of the individual spinning units for determining the transverse dimension of the running yarn produced at the spinning units. In addition, intermediate storage means are provided for electronically storing yarn measurement data at each of the individual spinning units. In order to process the yarn measurement data, a process computer is provided at a mobile servicing instrument which is selectively movable to respective servicing positions at the spinning units. The process computer and mobile servicing instrument also includes means for carrying out servicing operations at the respective spinning units in the event of detected yarn flaws or the like.

Abstract: An open-end spinning device wherein yarn is produced in a spinning compartment and withdrawn therefrom by yarn-withdrawal rollers and a winding device. The yarn storage device is interposed between the yarn-withdrawal rollers and the winding device. A knock-off motion is positioned between the spinning compartment and the yarn withdrawal rollers for producing a signal responsive to changes in tension in the yarn. THe yarn storage device includes a roller storage which is driven in a forward direction for accumulating a supply of yarn that is to be fed to the winding device. The roller storage can also be rotated in a reverse direction for withdrawing yarn therefrom during a piecing operation. A yarn gripper is provided for gripping the yarn upon a change in tension in the yarn.

Abstract: An apparatus for start-spinning a thread is arranged movably relative to each individual spinning unit along an open-end spinning machine in order to be able to perform start-spinning operations there if required. In order to avoid having to start spinning at the generally very high operating speeds of the spinning rotors, because the start-spinning operation would be made more difficult by these high speeds, in accordance with the invention the spinning rotor runs up to speed from a standstill during the start-spinning operation after a brake has been released, so that spinning is started during a period in which the spinning rotor has not yet achieved its operating speed. The start-spinning speed is therefore clearly lower than the operating speed of the spinning rotor.

Abstract: In order to be able to start-spin on the individual spinning units of an open-end spinning machine under conditions which deviate from the operating conditions and which are, in particular, significantly more favorable for start-spinning, the end of the thread is placed on a ring of fibres located in the spinning rotor at a spinning rotor speed which is reduced relative to the operating speed. At the same time, the sliver feed is reduced in such a manner that the amount of sliver feed corresponds to the reduced speed of the spinning rotor. This reduced sliver speed is produced by a mobile start-spinning unit which is equipped with means which intervene in the drive and/or control of the drive or control means causing feed of the sliver.