Apparatus for electroplating an article

Abstract

An apparatus for electroplating an article, such as a printed circuit board, includes a tank filled with electrolytic solution, a clamp for retaining the article fixed in place within the solution and a movable roller assembly disposed within the solution. The roller assembly includes a pair of vertically disposed, parallel rollers that are rotatably coupled to a rigid frame, with one roller preferably being spring biased towards the other roller. In use, the application of electrical current causes metal ions present in the solution to plate out on the article. To promote greater plating within through-holes or other similar surface depressions in the article, the roller assembly is linearly displaced by a motor-driven linkage so that the pair of rollers squeegee opposing surfaces of the article.

1 . An apparatus for electroplating an article, the article including substantially flat front and rear surfaces, the apparatus comprising: 
 (a) a tank shaped to define an interior cavity;    (b) a clamp adapted to fixedly support the article within the interior cavity of the tank;    (c) a roller assembly adapted to squeegee the front and rear surfaces of the article; and    (d) a linkage for linearly displacing the roller assembly within the interior cavity of the tank.    
   
   
       2 . The apparatus as claimed in  claim 1  wherein the roller assembly comprises, 
 (a) a rigid frame, and    (b) a pair of parallel rollers coupled to the rigid frame.    
   
   
       3 . The apparatus as claimed in  claim 2  wherein each of the pair of parallel rollers is vertically disposed and is adapted to contact a corresponding surface on the article in order to squeegee material that has accumulated on the surface during the electroplating process.  
   
   
       4 . The apparatus as claimed in  claim 3  wherein each of the pair of parallel rollers can spin freely relative to the rigid frame.  
   
   
       5 . The apparatus as claimed in  claim 3  wherein the pair of parallel rollers is spaced apart a fixed distance.  
   
   
       6 . The apparatus as claimed in  claim 3  wherein the spacing between the pair of parallel rollers can be adjusted.  
   
   
       7 . The apparatus as claimed in  claim 6  wherein at least one of the pair of parallel rollers is spring biased towards the other of the pair of parallel rollers.  
   
   
       8 . The apparatus as claimed in  claim 3  wherein each roller comprises, 
 (a) a core, and    (b) a sleeve disposed over the core.    
   
   
       9 . The apparatus as claimed in  claim 8  wherein the core is constructed out of a titanium-sleeved copper.  
   
   
       10 . The apparatus as claimed in  claim 9  wherein the sleeve is constructed out of polyvinyl alcohol (PVA).  
   
   
       11 . The apparatus as claimed in  claim 1  wherein the apparatus additionally comprises, 
 (a) a direct current (DC) power supply which comprises a positive terminal and a negative terminal,    (b) a cathode bar, the clamp being conductively coupled to the negative terminal of the DC power supply through the cathode bar, and    (c) one or more metal rods disposed within the interior cavity of the tank, each of the one or more metal rods being electrically connected to the positive terminal of the DC power supply.    
   
   
       12 . The apparatus as claimed in  claim 1  wherein the linkage comprises, 
 (a) a motor,    (b) a rotatable disk fixedly mounted on the motor,    (c) a travel board slidably mounted on the rotatable disk, and    (d) a rail fixedly connected to the travel board, the rail being fixedly    connected to the roller assembly.    
   
   
       13 . The apparatus as claimed in  claim 12  wherein the tank comprises a flat bottom panel and four side panels that together define the interior cavity.  
   
   
       14 . The apparatus as claimed in  claim 13  wherein the tank additionally comprises a pair of fixedly mounted support blocks.  
   
   
       15 . The apparatus as claimed in  claim 14  wherein the pair of support blocks limit the rail to displacement along a linear path.  
   
   
       16 . The apparatus as claimed in  claim 15  wherein the rotatable disk includes a fixed pin which is sized and shaped to protrude through a longitudinal slot formed in the travel board.  
   
   
       17 . A method of manufacturing an article, the article including substantially flat front and rear surfaces; said method comprising the steps of: 
 (a) electroplating the article, the electroplating step resulting in a layer of metal being deposited on the front and rear surfaces of the article, and    (b) squeegeeing at least a portion of the layer of metal deposited on the front and rear surfaces of the article using a roller assembly.    
   
   
       18 . The method as claimed in  claim 17  wherein the roller assembly is linearly movable.  
   
   
       19 . The method as claimed in  claim 18  wherein the roller assembly comprises, 
 (a) a rigid frame, and    (b) a pair of parallel rollers coupled to the rigid frame.    
   
   
       20 . The method as claimed in  claim 19  wherein, as part of the squeegeeing step, each of the pair of parallel rollers contacts a corresponding surface on the article.