Plating apparatus

Abstract

A plating apparatus includes a plating bath in which a plating solution is stored, a metal pipe having a cylindrical shape and including a hollow portion, the metal pipe defining and functioning as a first electrode, a mesh pipe having a cylindrical shape and including a hollow portion, the mesh pipe being made of an insulating material, and a second electrode. The metal pipe, the mesh pipe, and the second electrode are accommodated in the plating bath, the metal pipe is located inside the hollow portion of the mesh pipe, a plating forming portion is provided between an inside of the mesh pipe and an outside of the metal pipe, the second electrode is located outside the mesh pipe, and an upward flow with which the plating solution is moved upward is generated inside the hollow portion of the metal pipe.

What is claimed is: 
     
         1 . A plating apparatus comprising:
 a plating bath in which a plating solution is stored;   a metal pipe having a cylindrical shape and including a hollow portion, the metal pipe defining and functioning as a first electrode;   a mesh pipe having a cylindrical shape and including a hollow portion, the mesh pipe being made of an insulating material; and   a second electrode; wherein   the metal pipe, the mesh pipe, and the second electrode are accommodated in the plating bath;   the metal pipe is located inside the hollow portion of the mesh pipe, and a plating forming portion is provided between an inside of the mesh pipe and an outside of the metal pipe;   the second electrode is located outside the mesh pipe;   an upward flow with which the plating solution is moved upward is generated inside the hollow portion of the metal pipe;   plating targets are moved upward with the upward flow of the plating solution through the hollow portion of the metal pipe;   the plating targets are discharged to an outside of the metal pipe and stirred;   the plating targets subsequently fall downward through the plating forming portion;   while the plating targets fall downward, the plating targets each are plated by application of a current between the metal pipe defining and functioning as the first electrode and the second electrode; and   an auxiliary electrode electrically connected to the metal pipe defining and functioning as the first electrode is provided inside the plating forming portion.   
     
     
         2 . The plating apparatus according to  claim 1 , wherein
 the first electrode is a cathode electrode; and   the second electrode is an anode electrode.   
     
     
         3 . The plating apparatus according to  claim 1 , wherein the auxiliary electrode is attached to an outside of the metal pipe and electrically connected to the metal pipe. 
     
     
         4 . The plating apparatus according to  claim 1 , wherein the auxiliary electrode is hung inside the plating forming portion. 
     
     
         5 . The plating apparatus according to  claim 1 , wherein the auxiliary electrode includes a plurality of auxiliary electrodes. 
     
     
         6 . The plating apparatus according to  claim 5 , wherein a number of the plurality of auxiliary electrodes is four. 
     
     
         7 . The plating apparatus according to  claim 5 , wherein the plurality of auxiliary electrodes are arranged radially around the metal pipe when viewed in a planar direction. 
     
     
         8 . The plating apparatus according to  claim 1 , wherein the auxiliary electrode is a metal plate. 
     
     
         9 . The plating apparatus according to  claim 8 , wherein
 the metal plate is a plate having a triangular or substantially triangular shape; and   the metal plate is located inside the plating forming portion such that one side of the triangular or substantially triangular shape is located on an upper side and a vertex opposing the one side is located on a lower side.   
     
     
         10 . The plating apparatus according to  claim 8 , wherein the metal plate is a rectangular or substantially rectangular plate. 
     
     
         11 . The plating apparatus according to  claim 1 , wherein two rod-shaped electrically-conductive support portions are integrally provided with an upper portion of the metal pipe. 
     
     
         12 . The plating apparatus according to  claim 1 , wherein the second electrode has a cylindrical shape. 
     
     
         13 . The plating apparatus according to  claim 1 , wherein the metal pipe, the partition wall pipe, and second electrode are arranged concentrically with aligned central axes.