Abstract: A method is described for controlling the tension of an advancing yarn, which is crimped in a friction false twist unit of a false twist crimping machine. In accordance with the method, the tension of the advancing yarn is measured downstream of the friction false twist unit and the yarn tension is converted via a time filter and by comparison with a predetermined desired value into an adjustment signal for correcting the friction false twist unit, the control range being determined by defined limit values of the adjustment signal. The adjustment signal is a current value and is corrected adaptively via a PI controller, the control behavior of which takes into account the quotient from the change of the yarn tension and the change of the current value of the adjustment signal.

Abstract: A method and apparatus for producing a multifilament yarn by a melt spinning-draw process, and which includes applying additional heat to the melt in the region of the spinneret. The relationship between the withdrawal speed and draw ratio may be changed, and with an adaptation of other process parameters, it is possible to increase productivity. The process may be applied to continuous and discontinuous processes.

Abstract: This invention relates to marking the yarn end of a package, which is wound at the end of a winding cycle over a narrow axial range of the package surface in the form of a yarn bead. For purposes of marking the yarn end (105) of the package (103), a marking strip (126) is used, over which the yarn (105) is wound. A winding mandrel (107) engages into the space between a yarn suction device (106) and the circumferential surface of the package, and is rotated oppositely to the direction of unwinding (112) of the package (103), thereby forming a yarn loop (110) with more than one winding. Inserted axially into the space between winding mandrel (107) and the circumferential surface of the package is the marking strip (126), over which the yarn is wound several times by reversing the rotation of the winding mandrel (107). The excessive yarn (105) of the yarn loop (110) is sucked into the yarn suction device (106), and subsequently the yarn end (105) is cut.

Abstract: A yarn false twist crimping machine which comprises a processing frame which mounts the yarn processing components, a creel for mounting the yarn packages, and a take-up frame which is laterally spaced from the processing frame on the side thereof opposite the creel so as to define an operator aisle therebetween. An elongate heater is mounted to the take-up frame and an elongate cooling plate is mounted to the processing frame, and a false twist unit is mounted to the processing frame below the outlet end of the cooling plate. The yarn is guided from the creel in a generally planar arrangement across the operator aisle and to a first yarn feed system which is mounted on the take-up frame. The yarn then advances through the heater and cooling plate to the false twist unit and so as to loop back through the plane defined by the yarns being fed from the creel.

Abstract: A spin system for thermoplastic yarns is provided with a melt line, in which the main flow of the melt is transported to a distributor pump. The distributor pump comprises several individual pumps, which divide the main melt flow into several partial flows. Each partial melt flow is supplied to a spinneret. Arranged on one of the driven shafts of the pump are mixing elements. The main melt flow is supplied to the pump via a chamber, in which these mixing elements are arranged.

Abstract: An elongate heater for heating an advancing synthetic filament yarn with reduced friction. The yarn is advanced in contact with a generally flat contact surface of the elongate heater, with yarn guides being arranged along the heater in spaced apart relationship, and so as to guide the yarn in a zigzagged path with a predetermined amplitude over the contact surface. The yarn guides may be constructed as cylinders, which extend perpendicularly to the contact surface of the heater.

Abstract: A yarn heating apparatus for use in a yarn false twisting machine, which has an axial channel in which the yarn advances along a zigzagged path. To guide the yarn in the axial channel, yarn guides are provided, which are shaped as spaced apart protuberances on two metal strips. The metal strips are supported in contact with the side walls of the axial channel.

Abstract: A yarn traversing apparatus which includes a pair of oppositely rotating blades for respectively moving the yarn in opposite directions along a main guide edge in a medial portion of the yarn traverse stroke. An auxiliary yarn guide is mounted in each of the ends of the traverse stroke. The main guide edge and the auxiliary guide edges extend through the traverse plane from opposite sides thereof, and they are configured so that the main guide edge guides the yarn and controls its speed along the medial portion of the stroke and the auxiliary yarn guides guide the yarn and controls its speed in the end regions of the stroke. The yarn tension thereby can be maintained substantially constant along the full length of the stroke.

Abstract: Described is a godet (2) for guiding and advancing endless filament yarns, which comprises one or several heating zones along its casing (3), the heat that is applied by the heating elements (7-10) to the godet casing (3) being scanned by a multiple temperature sensor (12), so as to control the temperature of godet casing (3) in zones. In accordance with the invention, the temperature sensor (12) consists of a flat circuit arrangement of resistors and conduction bands, which are enclosed by a coating resistant to even high temperatures. The exposed tapping contacts (18) lead to the outside of godet (2) and are connected, via measuring lines, with an evaluation unit, whereas the temperature sensor (12) itself is attached to the inside surface of the rotatably driven godet casing (3).

Abstract: A method of controlling the quality during the production of a plurality of yarns in a corresponding number of identical processing stations (4, 5, 5') is disclosed. This method allows at least one signal (10, 10', 10") to be detected simultaneously and continuously in all processing stations (4, 5, 5') of such a production line, as well as to acquire at least one additional signal (7, 8, 9, 11) in one or more processing stations (4), the so-called reference stations. By correlating all signals acquired in these reference stations, the result of the correlation is evaluated based on the knowledge of possibly existing interdependencies, with respect to one or more typical properties of the furnished product. It is possible to determine therefrom set values for the further influencing of the process in the reference station as well as to obtain indications of the quality of the product.

Abstract: An apparatus for filtering plastic melts, which comprises a filter housing (1) having at least one cylindrical filter receiving chamber (8), and with a tubular filter cartridge (2) mounted in the chamber. An annular melt flow space (9) for the plastic melt is defined between the outer periphery of the filter and the inside wall of the chamber, such that the melt flows radially inwardly through the filter medium of the filter cartridge and into the central passage of the filter cartridge and then to an outlet opening of the housing. An additional melt flow outlet channel (12) is positioned adjacent the downstream end of the filter cartridge, and in one embodiment, the melt is able to flow via the additional melt flow outflow channel to the outside of the housing. In a second embodiment, the melt can flow via the additional melt flow outflow channel and an additional filter (11) and return to the main flow.

Abstract: A yarn heating apparatus for use in a false twist crimping machine wherein the advancing yarn is guided along a laterally zigzagged path through the apparatus by means of yarn guides which are alternately arranged on opposite sides of the yarn. The yarn guides are of cylindrical configuration so as to present broadly curved contact surfaces in engagement with the yarn.

Abstract: A method and apparatus for winding a yarn wherein at the end of the winding cycle the yarn end is secured to the package surface, so as to prevent yarn layers from automatically sliding down in subsequent handling and transportation of the packages. In accordance with the invention, the advancing yarn (1) is lifted out of the yarn traversing mechanism (2) at the end of the winding cycle, and guided and wound in a narrow axial range of the package (8). In the slowdown phase of the package (8), a pressing device (12-14) is pivoted against the package surface, which presses the yarn end by an adjustable force into the formed yarn bead.

Abstract: An apparatus for stuffer box crimping synthetic filament yarns is disclosed, which includes an air nozzle for pulling in and advancing multi-filament yarns at a high speed, and a downstream stuffer box in which the gaseous transport fluid is separated and the yarn is compressed to a compact yarn plug. To increase the production speed and production reliability, the speed at which the yarn is advanced through the air nozzle, and the yarn tension which is produced by the air nozzle is increased. This occurs in accordance with the invention in that the duct for the common advance of the yarn and the transport fluid is configured such that the flow duct narrows in the shape of a nozzle in a first segment down to a restriction at which the outflowing transport fluid reaches the speed of sound, and the duct then widens in a second segment at a small angle of opening.

Abstract: A method and apparatus for controlling the traversing frequency during the winding of a cross-wound package. In so doing, a signal is detected which is generated by the motion of the yarn while being wound onto a yarn package. Thereafter, the signal is analyzed by frequency, and/or amplitude, or other characteristics. Finally, the traversing frequency of the yarn takeup system is adjusted or varied as a function of the analysis result. In the preferred embodiment, the signal is proportional to a development of airborne sound or a development of solid-borne sound, each of which is generated in response to the motion of the advancing yarn on the package being formed. The method of the present invention allows disturbances in the winding operation to be avoided, such as the formation of so-called ribbons and similar phenomena.

Abstract: A heater (1) for an advancing thermoplastic yarn which is guided along a heated surface over ring segments (2). The flow of heat to the yarn is adjustable by changing the geometric parameters of the heat transfer.

Abstract: A method of servicing the individual winding stations of a multi-station winding machine, and wherein a plurality of identically equipped service carts is provided in a parking track, and such that upon receiving a call signal, each service cart may be moved from the parking track and along a service track and to the winding station which issued the call. The cart is then adapted to service the winding station, such as by doffing full yarn packages. The cart then may be moved to a transfer position where the full packages are received from the service cart for packing, or transport to a further processing machine.

Abstract: Doffer system for a textile machine, in particular for a multiposition textile machine, comprising a guiding device (3, 4, 5), which is arranged in front of and above a machine front, a transport unit (14) traveling along the guiding device (3, 4, 5), a hoisting device (17, 19) which allows to lower and raise the carrying frame (20), and at least one receiving mandrel (23, 24) which is arranged on the carrying frame (20) horizontally extending therefrom.

Abstract: A method and an apparatus for heating and drawing a synthetic filament yarn, and wherein the yarn receives a film of water by wetting with heated water vapor before entering into a heating chamber and so that the water vapor initially condenses on the yarn as it enters the heating chamber. To this end, a water nozzle or a hot vapor nozzle may be used, which is arranged upstream of the heating chamber.

Abstract: A yarn winding method for an apparatus with a rotatable turret accommodating two winding spindles which are alternately moved to a winding range and to a doffing range for replacing full packages with empty tubes, the doffing range having two stopping positions, and the exchange of fully wound packages and empty tubes occurring in two steps.