Positioning method and positioning device for positioning printing plate relative to surface plate

A method for positioning a printing plate, which has been placed on a surface plate, relative to said surface plate, comprising:

• a step of rotating said printing plate by pushing an edge thereof for thereby substantially eliminating an angular error;
• and
• a step of providing a holding structure at said surface plate for holding said printing plate at a point on either a front or back face surface of said printing plate,
• wherein the step of providing a holding structure includes providing a blunt member for the holding structure above said printing plate and pressing the blunt member against the printing plate at said point.

A method for positioning a printing plate, which has been disposed on a surface plate, relative to said surface plate wherein the printing plate is movable along a first direction relative to said surface plate, the method comprising steps of:

• (a) rotating the printing plate, while holding the printing plate at a point, about said point by pushing an edge of said printing plate for thereby substantially eliminating an angular error with respect to said surface plate;
• (b) continuing said pushing, thereby positioning said printing plate in said first direction;
• (c) subsequently moving said surface plate in a second direction substantially orthogonal to said first direction, thereby positioning said printing plate in said second direction using a plurality of printing plate detection sensors;
• and
• (d) setting a resultant position of said surface plate as an initial position.

A printing plate positioning device for positioning a printing plate relative to a surface plate, wherein the printing plate has been moved onto the surface plate from a predetermined transport path along a transport direction, the device comprising:

• (a) a movable body disposed proximate a side of said surface plate, said movable body being movable towards and away from said surface plate to thereby move said printing plate;
• (b) a plurality of sensors, disposed proximate said surface plate, operable for detecting said printing plate presence at predetermined positions;
• and
• (c) a first holding portion and a second holding portion provided at said surface plate, for holding a non-edge surface of said printing plate, wherein said first holding portion is capable of holding said surface of said printing plate while said printing plate is being moved by said movable body.

A printing plate positioning device for positioning a printing plate, which has been disposed on a surface plate, relative to said surface plate wherein the surface plate is movable along a first direction, the device comprising:

• a holding device provided at a surface of said surface plate, said holding device for holding said printing plate on said surface plate such that said printing plate is rotatable with respect to said surface plate about one point of said printing plate;
• a first pushing device disposed proximate a side of said surface plate, said first pushing device for pushing an edge of said printing plate while said printing plate is held by said holding device and thereby rotating said printing plate about said one point of said printing plate for thereby substantially eliminating in a direction of rotation an angular error with respect to said surface plate;
• a second pushing device disposed proximate a side of said surface plate, said second pushing device for pushing an edge of said printing plate, after said first pushing device has substantially eliminated said angular error, for thereby positioning said printing plate along a second direction substantially orthogonal to said first direction of the surface plate;
• and
• a detection portion operable for detecting a position along said first direction of said printing plate at a time at which said printing plate is moved along said first direction by movement of said surface plate after said printing plate has been positioned along said second direction,
• wherein said printing plate is positioned in accordance with said detection portion, and a resultant position of said surface plate is set as an initial position.