Apparatus for inspecting the exterior finish of containers and associated method

Apparatus for inspecting exterior finish of containers moving in a predetermined path, said apparatus comprising:

• at least one inspection gauge disposed above the path, each said inspection gauge having a pair of elongated, opposed gauge plates mounted for pivotal movement relative to one another at first pivot points on upper ends thereof, said gauge plates having gauging means thereon for engaging containers passing therebetween at at least one pair of generally diametrically opposed locations on said container, with each said pair of locations being disposed at a level on said containers separate from other said pairs of locations, sensor means operative responsive to relative pivotal movement of said gauge plates for detecting defective containers, said sensor means detecting a defective container when relative separation distance between said gauge plates where said gauge plates contact said container caused by said container passing therebetween falls outside predetermined limits, return spring means for urging said gauge plates into a closed position, stop means for maintaining a predetermined relative separation distance between said gauge plates when in said closed position, and dampening means for reducing rebound movement of said gauge plates upon closure thereof, said dampening means includes a magnetic damper on said stop means;
• said gauge plates having a total length along the path such that each container passing therebetween is inspected about its entire circumference at each level where said container is engaged by said gauge plates;
• said sensor means having at least one adjustable microswitch on said stop means which is activated when separation distance of said gauge plates falls outside said predetermined limits;
• transport means for moving said containers sequentially through each said gauge and axially rotating each said container about its vertical axis, said transport means including a pair of endless drive belts disposed generally longitudinally adjacent to said inspection gauges and positioned to engage opposite sides of said containers travelling through said inspection gauges, one said drive belt travelling faster than another said drive belt, whereby each container engaged by said drive belts will be propelled longitudinally along said drive belts and simultaneously be rotated about its vertical axis, said transport means further includes a container stabilizer wheel having a soft tire thereon rotatably mounted so as to engage said containers upon disengagement from said drive belts, whereby rotational movement of said containers is stopped;
• and
• each said inspection gauge being suspended above the path by a suspension system which permits each said gauge plate to pivot in a transverse direction about at least one second pivot point at or above said first pivot point to receive non-concentric containers therethrough, said suspension system includes at least one suspension bar having one end thereof pivotally connected to an inspection gauge and having another end thereof pivotally connected to a frame for supporting said gauges, whereby transverse pivotal movement of said gauges may be achieved.