Can inspection device

A can inspection device comprising:

• a rotation device rotating cans;
• an imaging device taking images of rotating cans;
• and
• an image processor processing taken images,
• which is provided in a can printing apparatus, performing inspections of print states of the cans and feeding back inspection results to the can printing apparatus,
• wherein the imaging device includes a first camera taking an image of the entire can and a second camera taking an image of an opening-side end portion of the can, wherein
• whether printing is performed properly as compared with a master image is inspected, densities in designated positions for respective colors are measured by using the image taken by the first camera,
• and misalignment values with respect to set positions of printing misalignment inspection marks printed on the opening-side end portion of the can for respective colors are measured by using the image taken by the second camera,
• wherein the rotation device includes a vertical drive side rotating shaft driven by a motor, a vertical driven side rotating shaft rotating integrally with the drive side rotating shaft, a cylindrical holding member attached concentrically to the driven side rotating shaft so as to hold a can and an encoder detecting a rotation of the drive side rotating shaft.

A can inspection device comprising:

• an imaging device taking images of rotating cans;
• an image processor processing taken images;
• and
• a conveyance device conveying cans,
• which is provided in a can printing apparatus, performing inspections of print states of the cans and feeding back inspection results to the can printing apparatus,
• wherein the imaging device includes a first camera facing to an entire can from a direction orthogonal to an axial direction of the can and taking an image of the entire can and a second camera facing to an opening-side end portion of the can from a direction orthogonal to the axial direction of the can and taking an image of the opening-side end portion of the can,
• wherein whether printing is performed properly as compared with a master image is inspected, densities in designated positions for respective colors are measured by using the image taken by the first camera, and misalignment values with respect to set positions of printing misalignment inspection marks printed on the opening-side end portion of the can for respective colors are measured by using the image taken by the second camera, and
• wherein the conveyance device comprises:
• a sampling line transferring part of a number of cans printed by the can printing apparatus to the imaging device;
• and
• a return line returning the cans determined as good products in the can inspection device to a conveyance line of the can printing apparatus.