摘要 |
An apparatus for controlling a let-off motion in a loom having a let-off motion motor includes a tension detector for detecting a warp tension to produce a tension correction signal, a control unit responsive to the tension correction signal for producing a speed signal, a driving amplifier for controlling the let-off motion motor in response to the speed signal, a warp coil diameter detector for issuing a warp coil diameter correction signal inversely proportional to the diameter of a warp coil on a beam to the driving amplifier, and a normal-reverse rotation control unit responsive to the warp coil diameter correction signal for selectively applying prescribed normal- and reverse-rotation signals dependent on a rotation command to the driving amplifier. With this arrangement, the motor is rotated at a desired constant speed for feeding out or rewinding the warp yarn for a desired length irrespectively of the warp coil diameter. In an inching mode of operation, the motor is rotated in a normal or reverse direction for an interval equivalent to one pick each time a main shaft of the loom turns past a certain rotational angle, so that the warp yarn is kept under a desired tension.
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