Method and apparatus of controlling warp tension on a weaving loom
AssigneeAlbany International Corp.
InventorJeffrey B. Duncan
Life of this patent
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Abstract
An apparatus for maintaining the warp threads in a multi-beam loom at a constant tension includes tension sensors for each beam, and a microprocessor-based control circuit which provides individual speed control signals to the motors during each beam. The circuit samples the warp tension at regular intervals and recalculates the optimum speeds for each motor by taking into consideration the transverse effects on each beam caused by adjacent beams.
Claims3
An apparatus for controlling the warp tension of a loom, said loom having several beams driven by variable speed motors for paying off warp threads, said apparatus comprising:
- warp tension sensing means for sensing the tension of the threads from each beam and for generating instantaneous tension signals corresponding to said thread tensions;
- control means for generating motor control signals for varying the speed of said motors to maintain the tension of the warp threads constant in accordance with said tension signals and in which the control means adjust to the speed of a motor j at T second intervals to drive the corresponding warp threads at a speed of Snj as follows:
- Snj=Soj+KcjLnj/T+Lnj/Ki+ISnj
- where n is the number of periods T since the loom was started, Soj is an initial speed, Kcj is a gain constant for a motor control loop formed by the tension sensor motor means and the control means;
- ISnj is a radius correction factor for beam j at m=n-1, and Lnj is the load factor on beam j as given by:
- ##EQU5## where Tnj=Toj-tnj, Toj being an initial set tension for beam j and tnj being the instantaneous tension on beam after n intervals, as determined by the load scanning means,
- Kf being an effective fabric modulus;
- Kj being an effective warp modulus;
- and STnj being derived by:
- Stnj+Tnj+Tu2+ . . . Tnw-Tnj
- where w is the total number of beams on the loom.
Dependencies are inferred from the claim text.