Abstract: Method and apparatus for detecting bulged and sunken sidewalls and incorrect widths on paneled containers.Containers to be inspected are moved along a conveyor. Two groups of three LVDT's (generally opposite from one another) are utilized to measure the distance between each of three points on the container sidewall and a reference line. The measurements are fed to a circuit which determines the deviation of one of the three points from a line passing through the remaining two points. The amount of deviation is utilized to determine whether or not the sidewall is bulged or sunken. Measurements from each pair of opposing LVDT's are fed to a circuit which determines the width of the container at three different heights. The width values are compared to predetermined limits in order to determine if the container width is acceptable.The timing of measurements is controlled by the use of photocell sensors, which detect the passage of a container past particular reference points.

Abstract: An improved "bird-swing" detector which has a downstream rejection system. An optical type bird-swing detector inspects glass containers as they move therethrough on a conveyor. A container exhibiting a bird-swing defect causes generation of a rejection signal. An oscillator may be set at a frequency in synchronism with the travel of the containers. A wave-shaping circuit forms the output of the oscillator into square waves at the frequency of the oscillator. A flip-flop has one input connected to the rejection signal and another input terminal connected to the wave-shaping circuit. The flip-flop output is connected to a multi-stage shift register. The signal from the wave-shaping circuit clocks the shift register. The switching of the flip-flop is delayed to allow entry of any information therefrom into the shift register before the flip-flop is reset. A reject or defective container signal is clocked through the shift register in synchronism with the travel of a defective container on the conveyor.