JPS5571938A - Method of inspecting defect on bottom of bottle - Google Patents

Abstract

PURPOSE:To exactly inspect defects on the bottom of a bottle by irradiating a light toward the bottom surface of the bottom and detecting the reflected light from the defects such as kinks or air bubbles existing in the bottom interior by a detector disposed oppositely to the bottom of the bottle. CONSTITUTION:The light from a light source 2 is transmitted through the side wall of the bottom of a bottle into the bottom interior and reflected on the boundary portion of defects 6 such as kinks or air bubbles or the like in the bottom, and partly reflected to any of photocells 3 disposed in numerous number on a bearer 5 for the bottle to thereby produce an abnormal signal therefrom. If there is no defect in the bottom of the bottle, no reflected light is transmitted to the photocells 3 to thus produce no abnormal signal. Since the light is reflected different in its direction and angle according the position and angle of the kink, it is necessary to scan the light to the bottle to be inspected by altering the position of the bottle to be inspected. This configuration can exactly inspect readily the defects such as kings, air bubbles in the bottom so as to prevent in advance trouble to be occurred after filling the bottle.