Selective plating system

Abstract

There is provided an apparatus for plating a portion of a work piece. The apparatus comprises a fixture having a cavity formed therein. The cavity is dimensioned to receive the portion of the work piece. An attaching means is provided for attaching the fixture to the work piece whereby a sealed chamber is formed between the fixture and the work piece. An inlet port in the fixture fluidly communicates with the sealed chamber. An outlet port in the fixture fluidly communicates with the sealed chamber. A circulation system fluidly connects to the inlet port and the outlet port and includes a source of a plating solution. The circulation system is operable to circulate a plating solution through the sealed chamber.

1 . An apparatus for plating a portion of a work piece, said apparatus comprised of: 
 a fixture having a cavity formed therein, said cavity dimensioned to receive said portion of said work piece;    attaching means for attaching said fixture to said work piece whereby a sealed chamber is formed between said fixture and said work piece;    an inlet port in said fixture fluidly communicating with said sealed chamber;    an outlet port in said fixture fluidly communicating with said sealed chamber; and    a circulation system fluidly connected to said inlet port and said outlet port, said circulation system including a source of a plating solution and being operable to circulate said plating solution through said sealed chamber.    
   
   
       2 . An apparatus as defined in  claim 1 , wherein said portion is an end of an elongated work piece.  
   
   
       3 . An apparatus as defined in  claim 2 , wherein said attaching means is an inflatable seal disposed between said fixture and said work.  
   
   
       4 . An apparatus as defined in  claim 1 , wherein said work piece is a cylindrical shaft.  
   
   
       5 . An apparatus as defined in  claim 4 , wherein said attaching means is an inflatable seal disposed between an inner wall of said fixture and an outer surface of said work piece.  
   
   
       6 . An apparatus as defined in  claim 1 , wherein said fixture includes: 
 an inner surface having an inner profile conforming to an outer surface profile of said portion of said work piece, said inner surface being a fixed distance from said portion of said work piece to define a gap between said fixture and said work piece.    
   
   
       7 . An apparatus as defined in  claim 6 , further comprising: 
 an electrode disposed in said gap a fixed distance from said portion of said work piece; and    electrical means for creating an electrical potential between said electrode and said work piece.    
   
   
       8 . An apparatus as defined in  claim 1 , further comprising: 
 a cavity formed in said circulation system, said container having a cavity formed therein fluidly communicating with said circulation system; and    a test strip disposed within said cavity of said container, said test strip made of a same material as said work piece, said test strip having a surface to be plated.    
   
   
       9 . An apparatus as defined in  claim 1 , wherein said circulation system is comprised of: 
 a tank containing a plating solution;    a circulation line connecting said tank to said inlet port and to said outlet port to form a closed loop;    heating means for heating said plating solution to a predetermined temperature; and    a pump disposed in said circulation system for circulating said plating solution along said closed loop and through said sealed chamber.    
   
   
       10 . An apparatus as defined in  claim 9 , wherein said heating means is a heater disposed in said tank.  
   
   
       11 . An apparatus as defined in  claim 1 , wherein said circulation system includes: 
 a first tank fluidly communicating with said sealed chamber, said first tank containing said plating solution;    a second tank fluidly communicating with said sealed chamber, said second tank containing a cleaning solution; and    a third tank fluidly communicating with said sealed chamber, said third tank containing a rinsing solution.    
   
   
       12 . An apparatus as defined in  claim 11 , further comprising 
 a first pump disposed in said circulation system for circulating said plating solution in said first tank to said sealed chamber;    a second pump disposed in said circulation system for circulating said cleaning solution in said second tank to said sealed chamber; and    a third pump disposed in said third path for circulating said rinse solution in said third tank to said sealed chamber.    
   
   
       13 . An apparatus as defined in  claim 11 , wherein said circulation system further comprises: 
 a first valve disposed in said circulation system between said fixture and said first tank, said second tank and said third tank, said first valve selectively controlling flow from said sealed chamber to said first tank, said second tank and said third tank; and    a second valve disposed in said circulation system between said fixture and said first tank, said second tank and said third tank, said first valve selectively controlling flow from said first tank, said second tank and said third tank to said sealed chamber.    
   
   
       14 . A method of plating an end portion of an elongated work piece comprising the steps of: 
 (a) attaching a fixture to said end portion of a work piece to create a sealed, fluid-tight chamber between said work piece and said fixture, said fixture having an inner surface with a profile conforming to an outer surface profile of said work piece, and further having fluid connection means for fluidly connecting said fixture to a source of a plating solution; and    (b) circulating said plating solution through said sealed chamber.    
   
   
       15 . In a method as defined in  claim 14 , further comprising: 
 a cleaning step of circulating a cleaning solution through said sealed chamber and circulating a rinsing solution through said sealed chamber prior to said step (b) of circulating.    
   
   
       16 . A method as defined in  claim 14 , further comprising: 
 an etching step of simultaneously circulating an etching solution through said sealed chamber and energizing an electrode disposed in said sealed chamber a fixed distance from said portion of said work piece prior to said step (b) of circulating.    
   
   
       17 . A method as defined in  claim 14 , further comprising: 
 a de-smuting step of simultaneously circulating a de-smut solution through said sealed chamber and energizing an electrode disposed in said sealed chamber a fixed distance from said portion of said work piece prior to said step (b) of circulating.    
   
   
       18 . A method as defined in  claim 14 , further comprising: 
 an activation step of simultaneously circulating an activation solution through said sealed chamber and energizing an electrode disposed in said sealed chamber a fixed distance from said portion of said work piece prior to said step (b) of circulating.    
   
   
       19 . A method as defined in  claim 14 , further comprising: 
 a pre-plating step of simultaneously circulating a pre-plating solution through said sealed chamber and energizing an electrode disposed in said sealed chamber a fixed distance from said portion of said work piece prior to said step (b) of circulating.