Abstract: A device for feeding weft yarns to a weaving machine which includes a rotatingly driven retainer that is constructed such that it has little mass. The retainer is coupled to a rotary drive unit such that the retainer cannot move radially with respect to a storage drum axis so that, when viewed in the direction of circulation of the withdrawal point, the retainer continuously extends through a circulatory path ahead of the weft yarn. The rotary drive unit is additionally connected to a control device which controls the acceleration and deceleration of the retainer in accord with a speed profile and determines the process of weft insertion in the weaving machine.

Abstract: According to a method and apparatus for controlling the insertion process of a weft yarn, the weft yarn is temporarily exposed to a braking friction and the yarn tension is mechanically picked-up. In order to prevent the friction from having a disturbing or damaging effect on the yarn, the yarn tension is only temporarily picked-up during certain phases of the insertion process, in order to derive information from the tension curve that is useful for the control of the insertion process. In a power loom, in particular a jet, rapier or gripper shuttle loom, a tension sensor for sensing the tension of the weft yarn can be switched during insertion between its sensing position and a passive position in which it does not touch the weft yarn. Preferably, the tension sensor is integrated in the insertion brake or even forms the braking element itself.

Abstract: A jet loom with a weft yarn insertion brake contains a braking element that is movable from a position of rest, on one side of the weft yarn, across the path of the weft yarn to a braking position. An electric motor, which drives the braking element, can be actuated during each insertion process of the loom. The electric motor preferably constitutes a fast response step or d.c. motor, whose direction of displacement can be switched and whose stroke can be individually adjusted for each set position of the braking element during the insertion process. Operation of the electric motor is controlled by an electronic control device. Programming within the control device can be modified between varying insertion processes so as to adapt the timing, stroke and driving direction of the electric motor. The driving force of the electric motor is transferred to the braking element by a constrained, inelastic link connecting the two.

Abstract: In a thread feed device for a textile machine, in particular for an air-jet weaving machine, which comprises a thread storage and feed device between a thread supply device and the picking device of the textile machine and which further comprises an assistant device arranged in the thread path extending from the thread supply device to the thread storage and feed device, the assistant device is provided with a friction drive for the thread. A method of driving a thread comprises the features that, in a friction drive constituting the assistant device, the circumferential speed of the friction drive is controlled such that it is higher or lower than the thread speed in the thread storage and feed device, and that, on the circumference of the friction drive, the thread is fed with a certain amount of slip maintained during the feed process or decelerated.

Abstract: In the case of a method of holding in position a rotatably supported thread storage surface in a thread storage and feed device, in which a group of components defining the storage surface is rotatably supported on a shaft adapted to be rotated in a housing and in which a winding-on member circulates together with the shaft, whereas magnets prevent the group of components from rotating together with the shaft, a rotational vibration damping connection is temporarily established between the housing and the group of components while the shaft is rotating In a thread storage and feed device (F), which is provided with an advance member (6) adapted to be driven such that it carries out a wobbling movement, there are arranged an externally supported rotational vibration damping member (X) and an abutment (Y) which is provided on the advance member (6).

Abstract: An apparatus for storing, feeding and measuring a weft yarn of a jet weaving machine is provided with an annular housing containing at least one weft yarn-stopping device. In said stopping device a stop member is arranged for a displacement between a passive position and a stop position. Said stop member is actuated by a current-energizable solenoid coil. Said stopping device is provided with a bistable and self-holding mounting arrangement for the stop member. Said stop member is connected with a polarized permanent magnet. For an actuation of the stop member in order to displace it away from its initial end position said current-energizable solenoid coil is electrically connected with a current-direction-reversing-circuit.

Abstract: In a method for controlling a yarn storage and feeding device, particularly for a mechanical loom, comprising a storage surface adapted to have windings of a yarn wound thereonto and withdrawn therefrom by a consumer, and a control unit for a winding drive mechanism operable to adjust the winding speed in accordance with the consumption rate and in response at least to the actual value of the number of yarn windings on the storage surface, for adjusting the actual value towards a predetermined desired value, the desired value is altered in response to at least one alteration of the winding speed to thereby obtain an optimum smallness of the yarn supply on the storage surface. In a yarn storage and feeding device for performing this method, the control unit cooperates with a reference value memory (18) for the supply of desired values (nV) varying in a predetermined manner.

Abstract: An apparatus for detecting a yarn movement comprises a yarn guide unit for the sliding guidance of a moving yarn, and a converter cooperating with the yarn guide unit for generating an electric signal. With the aim of improving the signal-noise ratio of an apparatus of this type, there is provided a member mounted for movement relative to the yarn guide unit and disposed such that the yarn is guided between the member and the yarn guide unit in simultaneous contact with the member and the yarn guide unit, the member being subjected to a biasing action relative to the yarn guide unit.

Abstract: A yarn storing and delivering device for a weaving machine includes a stationary base body and a hollow shaft which is rotatably mounted in the base body and which carries a laterally projecting yarn feeder element. Yarn is guided into the hollow shaft and wound by the yarn feeder element onto a storing surface of a storing drum which is maintained stationary relative to the base body. The yarn is axially withdrawn from the storing drum over a free edge of the storing surface and through a substantially central guide opening. A threading device equipped with air jet nozzles is provided for automatically threading the yarn up to a location within the guide opening. The threading device includes a compressed air conveying system disposed between the guide opening and a location adjacent the outlet of the yarn feeder element. The compressed air conveying system includes a plurality of stationary directional jet nozzles which, when activated, provide an air flow which delivers the yarn to the guide opening.

Abstract: A yarn storage device is provided having a storage drum and a ring surrounding the storage drum. It also has a plurality of yarn stop devices each having a blocking element, which is adapted to be introduced into an annular gap between the storage drum and the ring upon actuation of the yarn stop device. A withdrawing device for the blocking element, which removes the blocking element from the gap after termination of the activation of the yarn stop device, comprises a belt of resilient material.

Abstract: A weft yarn insertion nozzle device for a jet weaving machine, comprises a supply, an outlet nozzle, a conduit connecting the supply and the outlet nozzle and a valve unit. The valve unit comprises a displaceable, soft-magnetic valve body and a coil for generating a magnetic field extending through the valve body, wherein the valve body is arranged within the conduit such that the flowing of pressurized medium therethrough exerts a force on the valve body which is opposite to the force as generated by the magnetic field.

Abstract: A yarn storing device (1) comprises a storage drum (2) and a sensor (5) arranged at the withdrawal end (3) of the storage drum (2). The sensor (5) has the form of an eyelet (6) for guiding the yarn (4) and generates a signal during the withdrawal of yarn (4) having a frequency corresponding to the number of turns of yarn withdrawn per time unit. For enhancing the reliability of detecting the withdrawal of yarn on the basis of the sensor signal, the eyelet (6) of the sensor (5) is movably mounted on a housing (7) of the sensor (5) and comprises a light-reflecting surface (11) wherein a light-emitting element (8) and a light-receiving element (9) are fixed to the housing (7) such that the light generated by the light-emitting element (8) falls on the light reflecting surface (11) and is directed towards the light-receiving element (9) when the eyelet (6) has a predetermined relative position with respect to the housing (7).

Abstract: A yarn storing and feeding device having a stationary storage drum onto which an intermediate yarn store is wound by a winding-on device, and from which the yarn is withdrawn through a gap around the withdrawal end of the storage drum. At least one yarn stopping device is associated with the gap for controlling the withdrawal of yarn. The stopping device includes a stopping element arranged radially inwardly with respect to the gap, and movable radially outwardly to extend across the gap in response to a magnetic actuator located radially outwardly with respect to the gap.

Abstract: The present invention relates to a method for controlling a yarn storing, feeding and measuring device, having a stationary storage drum, a yarn sensor and at least one yarn stopping device, wherein the method includes the determining of the number of pulses which are to be generated by the sensor before actuating the stopping device.The reliability and speed of the device is enhanced by actuating the stopping device with a pre-determined delay-time after receipt of the pulse, the number of which corresponds to said pre-determined number.

Abstract: A yarn accumulating and feeding apparatus (1) has a stationary accumulating drum adapted to have a yarn (27) formed into a yarn supply (26) thereon, the magnitude of which is monitored between a minimum and a maximum by means of at least one mechanical probe element (28,28',28",28'",28"") adapted to be displaced by the yarn supply between two positions (I,II) and operatively associated with a switching device located outside of the accumulating drum. The probe element is mounted in the accumulating drum for displacement between one position projecting past the surface of the accumulating drum, and another position extending flush with the accumulating drum surface (15) against the bias of a return force, while a switching device contains a sensor element (20,20',21,21',20",20'") for generating a reaction signal in response to displacement of the probe element but without contacting the probe element.

Abstract: A yarn storing, feeding and measuring device, particularly for jet looms, has a stationary drum onto which an intermediate yarn store is wound by a winding-on device and from which the yarn is withdrawn, yarn sensing means detecting the withdrawal of the yarn from the drum by generating pulse signals indicating that the yarn passes a detection area of the yarn sensing means, a plurality of yarn stopping devices arranged at angular intervals around the storage drum and a control device adjustable to desired yarn lengths to be withdrawn, said control device being responsive to said pulse signals such that an actuating signal is transmitted to a selected yarn stopping device whose angular position corresponds to the position of the yarn when said desired yarn length has been withdrawn.

Abstract: This device has a storage drum (2) onto which an intermediate weft yarn store can be wound by a winding-on member (3) and from which the weft yarn (WY) is withdrawn spiralling around the withdrawal end of the storage drum, at least one yarn stopping device (10/14) being arranged at said withdrawal end and consisting of a stopping element (14) and of actuator means (11) moving said stopping element into and out of the path of the yarn being withdrawn, and an actuator control unit (B) transmitting an actuating signal to said stopping device when a weft yarn length corresponding to the length of the shed (WMS) of woven fabric in the machine has been withdrawn from the storage drum. The actuator control unit (B) is electrically connected to a yarn sensing detector (WD), preferably of optical type and known per se, positioned at the arrival end (AE) of the shed (WMS) for the weft yarn (WY) at a predetermined distance (d) from said arrival end.

Abstract: Method of controlling a plurality of relay nozzles (RNx) is a jet weaving machine. These nozzles are consecutively actuated for supporting the insertion of the weft yarn (WY) into the shed of the weaving machine and up to the arrival end (AE) of said shed by means of consecutively opening solenoid valve associated with nozzles. The valves are controlled on the basis of calculated information representing the momentary real position of the weft yarn (WY) during it path in the shed. The invention also relates to an apparatus for carrying out said method.

Abstract: A thread storage and delivery device, with a drum-like storage body, of which the peripheral surface provides a storage surface for a thread stock and presents inside at least one cavity of which the access is ensured from the outside by at least one opening. In known devices of this type, dust and plush penetrate through the opening into the cavity and are a danger for the operation of the device, for example for the roller bearings. The shaping of the storage body as a crucible with a closed periphery and a closing lid laid from the outside is known. This configuration is technically expensive both from the construction and assembly points of view. This principle is further unapplicable when the storage body is formed of a plurality of parts which are movable with respect to each other and meshed into each other.

Abstract: The invention relates to a yarn supply device group for attaching to a textile machine, in particular a ring knitting machine with electrically controllable switching and actuating devices in every supply device which are connected in a signal-transmitting circuit by a bunch of lines common to all supply devices to a central control mechanism. Previously, every supply device in the group had to be "marked" manually prior to the start of operation. In addition, a bunch of lines with large dimensions was necessary, since each supply device needed at least one separate line.