OPPOSITE PLATE SUPPORTING DEVICE

摘要

PROBLEM TO BE SOLVED: To avert the mispositioning of opposite plates by attracting an attraction block by the magnetic force generated by an electromagnet. SOLUTION: A lower mask plate 52 integral with a lower plate attraction frame 54 is supported via a ball caster 82 to a lower mask plate supporting base 60 and is moved while the mask plate is held parallel with an upper mask plate through the pressing by a moving unit 114. The electromagnet 152 is kept in an energized state to generate the magnetic force before the movement of the lower mask plate 52 is started. This magnetic force is held before the start of the movement. The attraction block 156 disposed on the rear surface of the lower plate attraction frame 54 is kept attracted to the electromagnet 152 by receiving this magnetic force and, therefore, the lower mask plate 52 is not mispositioned while the lower mask plate is kept attracted to a lower mask plate supporting base 60. In the meantime, the electromagnet 152 is de- energized to erase the magnetic force and to release the attraction of the lower mask plate 52 during the movement of the plate. The electromagnet 152 is energized again after the completion of the movement.