A can inspection device includes a rotation device rotating cans, an imaging device taking images of rotating cans, and an image processor processing taken images. The imaging device includes a first camera taking an image of an entire can and a second camera taking an image of an opening-side end portion of the can. The image processor includes an image inspection means for inspecting whether printing is performed properly as compared with a master image by using the image taken by the first camera, a density measurement means for measuring densities in designated positions for respective colors by using the image taken by the first camera, and a printing misalignment value measurement means for measuring 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 by using the image taken by the second camera.
G01N 21/952 - Inspecting the exterior surface of cylindrical bodies or wires
B41F 17/22 - Printing apparatus or machines of special types or for particular purposes, not otherwise provided for for printing on filamentary or elongated articles or material, or on articles with cylindrical surfaces on articles of finite length on articles of uniform cross-section, e.g. pencils, rulers, resistors by rolling contact
B41J 3/407 - Typewriters or selective printing or marking mechanisms characterised by the purpose for which they are constructed for marking on special material
B41F 31/12 - Applications of feed or duct rollers adjustable for regulating supply
B41F 31/14 - Applications of messenger or other moving transfer rollers
B41F 33/00 - Indicating, counting, warning, control or safety devices
B41F 13/14 - Registering devices with means for displacing the cylinders
G01N 21/956 - Inspecting patterns on the surface of objects
G01N 21/90 - Investigating the presence of flaws, defects or contamination in a container or its contents
An image processor 53 processing taken images includes an image inspection means 54 for inspecting whether printing is performed properly as compared with a master image by using the image of the entire can taken by a first camera, a density measurement means 55 for measuring densities in designated positions for respective colors also by using the image of the entire can taken by the first camera, and a printing misalignment value measurement means 56 for measuring misalignment values with respect to set positions of printing misalignment inspection marks printed on an opening-side end portion of a can for respective colors by using the image of the opening-side end portion of the can taken by the second camera.
B41F 17/22 - Printing apparatus or machines of special types or for particular purposes, not otherwise provided for for printing on filamentary or elongated articles or material, or on articles with cylindrical surfaces on articles of finite length on articles of uniform cross-section, e.g. pencils, rulers, resistors by rolling contact
G01N 21/88 - Investigating the presence of flaws, defects or contamination
B41J 3/407 - Typewriters or selective printing or marking mechanisms characterised by the purpose for which they are constructed for marking on special material
B41F 33/00 - Indicating, counting, warning, control or safety devices
B41F 31/12 - Applications of feed or duct rollers adjustable for regulating supply
B41F 31/14 - Applications of messenger or other moving transfer rollers
B41F 13/14 - Registering devices with means for displacing the cylinders
G01N 21/90 - Investigating the presence of flaws, defects or contamination in a container or its contents
Provided is a can-printing apparatus equipped with a can inspection device capable of density and printing deviation measurements necessary for improving the printing precision of the printer. An image-processing unit (53) for processing an image that has been photographed is provided with: an image inspection means (54) for comparing a can with a master image using an image of the whole can taken with a first camera to check whether the can is printed correctly; a density measurement means (55) for measuring the density of each color at designated positions similarly using the image of the whole can taken with the first camera; and a printing deviation measurement means (56) for measuring, using an image of the open end of the can taken with a second camera, deviations with respect to positions set for printing deviation inspection marks printed for each color on the open end of the can.
B41F 17/22 - Printing apparatus or machines of special types or for particular purposes, not otherwise provided for for printing on filamentary or elongated articles or material, or on articles with cylindrical surfaces on articles of finite length on articles of uniform cross-section, e.g. pencils, rulers, resistors by rolling contact
B41F 31/14 - Applications of messenger or other moving transfer rollers
B41F 33/14 - Automatic control of tripping devices by feelers, photoelectric devices, pneumatic devices, or other detectors
G01N 21/88 - Investigating the presence of flaws, defects or contamination
G01N 21/89 - Investigating the presence of flaws, defects or contamination in moving material, e.g. paper, textiles
G01N 21/90 - Investigating the presence of flaws, defects or contamination in a container or its contents
G01N 21/956 - Inspecting patterns on the surface of objects
The present invention eliminates backlash between a drive helical gear and a driven helical gear and facilitates rotation of a driven gear member to increase rotational accuracy of a plate cylinder. A plate cylinder drive unit includes a plate cylinder drive shaft, a driven gear member having a driven helical gear that meshes with a drive helical gear and attached around the plate cylinder drive shaft, a position adjustment member moving the driven gear member to fix it at a predetermined position, a whirl-stop member attached to the plate cylinder drive shaft, a sandwiching member removably fixing the whirl-stop member to the driven gear member, a backlash eliminating helical gear disposed on one side of the driven helical gear, first springs bringing the backlash eliminating helical gear in pressure-contact with the driven helical gear, and second springs biasing the backlash eliminating helical gear to rotate it in a predetermined direction.
A backlash of a driving side helical gear and a driven side helical gear is eliminated, and a rotation of a driven side gear member is smoothed, to increase rotation accuracy of a plate cylinder. A plate cylinder driving device (3) is provided with a plate cylinder driving shaft (5), the driven side gear member (7) which has the driven side helical gear (6) engaged with the driving side helical gear (1) and is attached around the plate cylinder driving shaft (5), a position adjustment member (11) which causes the driven side gear member (7) to move to be fixed to a predetermined position, a baffle member (9) attached to the plate cylinder driving shaft (5), a nipping member (10) which fixes the baffle member (9) to the driven side gear member (7) so as to be attachable and detachable, a backlash removal helical gear (8) disposed on one side of the driven side helical gear (6), a first spring (44) which causes the backlash removal helical gear (8) to be press-contacted to the driven side helical gear (6), and a second spring (46) which biases the backlash removal helical gear (8) so as to rotate in a predetermined direction.
B41F 13/14 - Registering devices with means for displacing the cylinders
F16H 1/08 - Toothed gearings for conveying rotary motion without gears having orbital motion involving only two intermeshing members with parallel axes the members having helical, herring-bone, or like teeth
F16H 55/18 - Special devices for taking-up backlash
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