PURPOSE: To enlarge the area of a conducting layer and to prevent the diffusion of charges on each spacer projection in a dust collecting electrode plate where one surface of an insulating substrate is laminated with a conducting layer and also which is dotted with a lot of spacer projections by almost enclosing each spacer projection by the individual conducting layer.
CONSTITUTION: In a dust collecting electrode plate 10, one surface of an insulating substrate 11 is laminated with a conducting layer 12. And on both ends of the insulating substrate 11 are formed inserting holes for an electrode bar 13. Further, in one inserting hole 13 is installed a reed-like piece extending, and even the upper surface of the reed-like piece is laminated with the insulating layer 12. And the insulating substrate 11 is dotted with a lot of boss-shaped spacer projections 15. That is, each spacer projection 15 leaves a space for passing liquefied air, between the dust collecting electrode plate 10 and an anode plate. In this case, the insulating substrate 11 is laminated with the conducting layer 12 in a state where each spacer projection is surrounded by the layer 12. In other words, each spacer projection 15 and the vicinity around it are set in a state where they are exposed, not laminated with the conducting layer 12.
KUROKAWA HACHIRO
ENOKIDA TATSUUMI
KAKIMOTO AKIHISA
