Shed sensing stop motion system for high speed looms

摘要

Automatic loom stopping apparatus for detecting yarn breakage or improper shedding defects and generating loom stop signals to be associated with a loom comprising two or three vertically spaced monitoring light beam units forming horizontal transverse light beams perpendicular to the warp yarns spanning the warp yarn path. One of the beams forms a center beam located to pass through the open shed and the other beam or beams located to be interrupted by or both of the shed sheets occupying the upper or lower limit shed positions. Detector signals responsive to interruption of the light beams by yarns are processed and applied to gating circuits and NOR or AND circuits to detect yarn breakage, broken heddles, and other shedding defects.