Patent ID: 7867368

Claim:
A plating apparatus for forming a plated coating on an inner circumferential wall of a hollow region of a hollow workpiece, said apparatus comprising: a cylindrical electrode having a longitudinal through-hole and disposed in such a manner as to form a cylindrical gap inside the hollow region of the workpiece; means for forming a helical flow of a plating liquid from a bottom end to a top end of the cylindrical gap when the plating liquid flows into the cylindrical gap communicating with the through-hole via the end portion of the cylindrical electrode; a supply channel for supplying a plating liquid through to a bottom end of the cylindrical gap; a porous member having a plurality of holes provided between the supply channel and the bottom end of the gap; and air supply means provided in the supply channel, wherein air is supplied to the supply channel by the air supply means, whereby bubbles are admixed in the plating liquid in the supply channel, and the plating liquid with admixed air bubbles is conducted to the cylindrical gap via the porous member.