Abstract: For supplying yarns, a yarn supply apparatus is contemplated that is designed particularly for knitting machines whose yarn demand fluctuates greatly over time. The yarn supply apparatus has a rotor-driven yarn wheel, which in the ideal case furnishes yarn directly to the knitting machine or its yarn guides without the interposition of yarn storage devices. The yarn tension is monitored by means of a yarn tension sensor, which provides measured value detection for a closed-loop controller that controls the supply by the yarn wheel. The controller is also embodied such that it can process signals that contain information about the future yarn demand. Thus in the event of imminent drastic changes in demand, of the kind that in flatbed knitting machines periodically occur at the edges of the knitted goods (turning points of the yarn guide), the controller can react by presupplying yarn or by ceasing to supply yarn. Yarn tension spikes and overly steep yarn tension drops can thus be compensated for.
April 2, 1998
Date of Patent:
January 4, 2000
Eberhard Leins, Hermann Schmodde, Friedrich Weber, Josef Fecker, Ludwig Ketterer
Abstract: A process or apparatus can control thread provision in a warp knitting machine by means of a computer (6). The computer operation involves pattern data (MD) supplied as a sequence of numbers. These numbers are provided to a recognition routine (ER), which for every warp course (line W) determines the lapping type (LA) that should be formed and the shogging distance (SW) prescribed. Tables are stored for providing a thread provision value (FZ) for each combination of lapping type (LA), thread take-off value (WA), and a shogging distance (SW). Based upon (a) the determined lapping type, (b) the inputted fabric take-off value, (c) the inputtable external operating parameters or influences, and (d) the determined shogging distance, the thread provision value for this warp course is read out and utilized for controlling thread provision.
Abstract: A monitoring needle (19) is rotatably mounted under spring tension in a housing (18). A light emitter/light receptor device is fixed to the housing (18) in the plane of the thread (5) and in the pivotal region of the monitoring needle (19), this device producing a control signal both in the case of irregularity in the thread and when crossed by the monitoring needle.
Abstract: A method and apparatus for measuring the tension on textile fabrics in a textile machine especially a loom. At least a part of a fabric is subjected to simultaneous transverse deflections, the speed of propagation of the simultaneous transverse deflections along the fabric is determined, and the tension on the fabric is determined in accordance with the determined speed of propagation. An exciter and a receiver is utilized for initiating the transverse deflections and determining the speed of propagation thereof.
Abstract: A regulating device for actuating the regulating element of the speed-changing unit of a warp-beam let-off motion as a function of the position of a lever of the balance for measuring the tension of warp threads. A jamming member is engaged over a bar which is driven in reciprocating motion by an eccentric. The jamming member is capable of selective sliding along the bar or jamming against said bar according to the orientation given to the jamming member by a rod attached to the balance lever. The energy required for regulating the speed-changing unit is supplied by a shaft which is driven by the main motor of the loom and drives the bar in reciprocating motion.
December 9, 1982
Date of Patent:
October 23, 1984
Societe Alsacienne de Construction de Materiel Textile
Abstract: An apparatus for regulating tension in warps of a weaving machine comprising: a tension lever swingably supported on a weaving machine and having a roller supported thereon for regulating the tension in warps delivered from a warp beam; a weight lever swingably supported on the weaving machine and having a load at one end thereof; and a link operatively connecting the tension lever and the weight lever. The tension lever has an elongated hole formed thereon, and the lever ratio of the tension lever is changed by moving the link along the elongated hole.The apparatus further includes a support member having two pairs of guide rollers and being connected to the link, so that the relative movement between the link and the tension lever can smoothly be carried out.
Abstract: A lever, pivoted intermediate its ends, rotatably mounts a roller at one end engaging the material being wound off a core. In one embodiment, the lever is spring biased in a direction to bias the roller against the material, and changes in the position of the opposite end of the lever are effective to adjust a potentiometer forming the control element of an asynchronous single phase variator. In another embodiment of the invention, the spring is omitted, and a pressure-resistance detector is mounted between the opposite end of the lever and a frame. In a third embodiment of the invention, the opposite end of the lever carriers a shutter cooperable with a photoelectric control, the lever being spring biased in this embodiment. The pressure-resistance detector can be substituted in the variator for the potentiometer.
Abstract: The pulse transmitter is synchronized with the weaving cycle of the machine drive and carries at least one sensing surface of variable shape. A detector is secured to the tension beam and is responsive to changes in warp tension. The detector carries a sensing element in the form of a proximity switch which is disposed over the sensing surface of the pulse transmitter. Depending upon the position of the proximity switch relative to the sensing surface, a pulse is emitted to the warp beam drive for stepping of the warp beam as the pulse transmitter rotates past the sensing element. This pulse is variable in the time-of-occurrence as well as in duration.
Abstract: A warp tension controller for a loom comprises a warp tension sensor for generating a first signal which is a measure of the warp tension, a source of a reference signal, and means for comparing said signals and producing an output signal representing deviation of said first signal from said reference signal. An operational amplifier has an inverting input connected to receive said output signal, and has an output connected to means for adjusting the warp tension. A feedback circuit connected between said input and said output of said amplifier comprises a resistor in parallel to an integrating capacitor.