Plastic coating for flat or layered capacitors - applied in pulsating fluidised bed with high frequency heating, to give uniform film

摘要

Flattened roll or layer capacitors are plastics coated in a fluidised bed by heating them in a high-frequency induction coil. They are held at an angle to ensure the intended distribution of the coating material over the capacitor surfaces. The top level of the fluidised bed is periodically raised and lowered by pulsed compressed air or by mechanical movement. The capacitor is held with its connecting wire in a collet at an angle alpha relative to the field of the h.f. induction coil. A fluidised bed of plastic material is maintained in a container where pulse compressed air is applied to below a filter plate. This fluctuating level results in more uniform overall coating thickness. The temp. equalisation is also speeded up.