Method and apparatus for inspecting woven cloth using a plurality of photoelectric sensors

摘要

A woven cloth inspecting apparatus eliminates the influences of disturbances such as illuminating light and fly. At least two photoreceptor elements are arranged in the direction of the weft yarn of woven cloth. The photoreceptor elements detect different area of the woven cloth and they apply current signals to two respective current-to-voltage converters which convert the current signals into voltage signals which are fed to a difference calculating circuit. The difference calculating circuit calculates the difference between the values of the voltage signals received from the two current-to-voltage converters and supplies the obtained difference signal to a comparator which compares the received difference signal with a reference value preset by two reference value setting circuits. Exceeding the reference value is indicative of a defect in the warp. Alternatively the photoreceptor elements are arranged in the warp direction and detect defects in the weft. Also, photoreceptor elements can be located in both the weft and warp directions.