Patent ID: 6025909
Filing Date: 2000-02-15
Classification: G01N

Abstract:
Apparatus for inspecting the finish of a container having a central axis and an open mouth surrounded by an axially facing sealing surface area for sealing engagement with a container cap, said apparatus comprising:a structured light source positioned to direct a collimated line-shaped light beam onto the sealing surface area of a container in such a way that the line-shaped beam at the sealing surface has a long dimension orthogonal to the container axis and a narrow dimension tangential to the container axis,light sensor means disposed to receive portions of said line-shaped light beam reflected from the sealing surface area of the container,said light source and said light sensor means being disposed above the sealing surface area of the container in a plane tangential to the container axis such that the light from the light source is incident on the sealing surface area where the sealing surface area is traveling in said plane tangentially to the container axis and light reflected from the sealing surface area of the container onto said light sensor means is incident at a position on said sensor means that varies with height of the sealing surface with respect to said light source and said sensor means, the long dimension of said line-shaped light beam accommodating wobble or misalignment of the container sealing surface area with said light source and said light sensor means, andmeans for detecting variations in height at the sealing surface area of the container as a function of position of incidence of the reflected light on said light sensor means.