Mosaic printing head membrane spring - has multiple curved slots forming zigzag path between inner and outer edges

摘要

A mosaic printing head has an outer sleeve housing a block carrying the excitation coils, above which is a ring shaped pole piece enclosing a moving cylindrical core. This core carries the printing needle which passes down the middle of the assembly forming the head. A disc shaped spring (9) is clamped between the pole piece and a non magnetic disc at the top. Below the spring, the pole piece is funnel shaped so that the spring is clamped only at its inner (16) and outer (28) peripheries. The spring has a set of concentric curved slots around it. These slots form a multiple staggered or zig-zag path around the region between the inner and outer peripheries.