Roller offset printing apparatus

A roller offset printing apparatus including:

• a base (3);
• a linear stage (4) movable forwards and backwards on said base;
• a stage driving means (5) for driving said linear stage;
• a master plate (6) and a work plate (7) disposed at a predetermined interval on said linear stage (4), said master plate (6) having ink pits (21) formed in a surface of said master plate (6) for reserving ink (20);
• a roller transfer drum (1) supported rotatably;
• and
• a roller transfer drum driving means (2, 52, 53) for driving said roller transfer drum (1) so that a roller offset printing including a first transfer operation, in which said roller transfer drum (1) rotates on the surface of said master plate (6) to transfer the ink (20) in said ink pits (21) of said master plate (6) onto the outer circumferential surface of said roller transfer drum (1), and a second transfer operation, in which said roller transfer drum (1) rotates on a surface of said work plate (7) to thereby transfer the ink (20) from the outer circumferential surface of said roller transfer drum (1) onto the surface of said work plate (7), is conducted,
• wherein said roller offset printing apparatus comprising:
• a rotation force transmission control means (30) for controlling on/off of transmission of rotation force from said roller transfer drum driving means (2) to said roller transfer drum (1);
• a rotation angle detection means (32) for detecting the rotation angle of said roller transfer drum (1);
• and
• a transfer control means (24) for turning off said rotation force transmission control means (30) at the time of start of said first and second transfer operations to thereby cut off transmission of the rotation force from said roller transfer drum driving means (2) to said roller transfer drum (1) and for turning on said rotation force transmission control means (30) after completing one of said first and second transfer operations to thereby return said roller transfer drum (1) to a transfer start position in accordance with an output signal of said rotation angle detection means (32).