Patent Publication Number: US-7713586-B2

Title: Method for a surface being plated locally

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is related to a method for a surface being plated locally and particularly to a method which is capable of plating a specific plated zone on a surface of a work piece without wasting plating material. 
     2. Brief Description of the Related Art 
     The conventional radiator assembly is made of two different materials, such as aluminum alloy and copper, that is, the radiator itself is made of aluminum and a base, which is attached to the radiator, is made of copper. In order to join the radiator and the base together, the joining end of the radiator is plated with a layer of nickel and then adhesive such as soldering paste is coated on the layer of nickel to adhere the base once the adhesive is cool down. 
     The method for plating the preceding radiator assembly is shown in  FIG. 1 . The work piece is processed with oil removal and water cleaning sequentially twice first. Then, the work piece is performed with zinc replacement and water cleaning sequentially twice (a step of zinc removal is performed after the first zinc replacement and water cleaning). After that, the work piece is immerged into plating solution completely to allow the surface of the work piece being plated. Once the plating job is finished, the work piece is taken out to be cleaned with water and dried with oven. 
     However, it is a problem of the conventional method for nickel plating that the entire radiator assembly has to be immerged in the nickel solution for plating the joining ends of the aluminum radiator and the copper base with nickel only. It results in longer plating time and excessively consumed nickel spending on the unnecessary plated area of the work piece such that not only production cost increases but also heat dissipation efficiency of the radiator assembly decreases due to the heat dissipation efficiency of nickel is worse than the materials of the radiator assembly. 
     SUMMARY OF THE INVENTION 
     Accordingly, an main object of the present invention is to provide a method for a surface being plated locally with which only a plated zone on a surface is capable of being immerged in the liquid of a plating tank. 
     Another object of the present invention is to provides a method for a surface being plated locally with which de-oxide solution and plating liquid consume economically. 
     In order to achieve the preceding object, a method for a surface being plated locally according to the present invention includes a fixture for holding at least a work piece and the fixture is supported with two opposite lateral walls of a plating tank. Hence, a plated zone on a surface of the work piece can be immerged into the liquid contained in the plating tank for the plated zone being coated with de-oxide layer and plating layer sequentially. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The detail structure, the applied principle, the function and the effectiveness of the present invention can be more fully understood with reference to the following description and accompanying drawings, in which: 
         FIG. 1  is a block diagram illustrating steps of conventional plating; 
         FIG. 2  is an exploded perspective view of a fixture employed in a method for a surface being plated locally according to the present invention; 
         FIG. 3  is an assembled perspective view of the fixture shown in  FIG. 2 ; 
         FIG. 4  is a perspective view illustrating the fixture shown in  FIG. 3  being ready to be attached to a plating trough; 
         FIG. 5  is a sectional view illustrating the fixture shown in  FIG. 3  being attached to the plating trough; 
         FIG. 6  is an exploded view of an another type fixture employed in a method for a surface being plated locally according to the present invention; 
         FIG. 7  is an assembled perspective view of the fixture shown in  FIG. 6 ; 
         FIG. 8  is a perspective view illustrating the fixture shown in  FIG. 7  being ready to be attached to a plating trough; and 
         FIG. 9  is a sectional view illustrating the fixture shown in  FIG. 7  being attached to the plating trough. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A method for a surface being plated locally according to the present invention including following steps: 
     A. repeat two times of operations of removing oil on a surface of at least a work piece and washing the surface with water before the work piece being placed in a de-oxide tank for processing the first de-oxide layer; 
     B. a fixture clamping the work piece is placed on a first plating tank in a way of crossing over the first plating tank and being supported with two opposite sides of the first plating tank to allow part of the surface of the work piece to be immerged into a liquid contained in a first plating tank such that the plated zone on the surface forms uniform strip shaped de-oxide layer. Then, lift the fixture away the first plating tank and wash the work piece with water; and 
     C. the fixture is placed on a second plating tank in a way of crossing over the second plating trough and being supported with two opposite sides of the second plating tank to allow the de-oxide layer on the surface of the work piece to be immerged into another liquid contained in the second plating tank such that a plated layer is formed on the de-oxide layer. Then, lift the fixture away the second plating tank before the work piece is washed with water and dried with oven. 
     The liquid in the first and second plating tanks is de-oxide solution and plating solution respectively. It can be implemented that the de-oxide solution is zinc solution and the de-oxide layer is a zinc layer coating the plated zone on the surface of the work piece part. Further, the plating liquid is nickel solution so that a nickel plating layer coats the zinc layer. 
     The work piece can be an integral radiator or a single cooling fin. 
     Referring to  FIGS. 2 and 3 , the fixture includes a first main member  11 , a second main member  12  corresponding to the first main member  11 , a channel shaped hanging arms  13  being attached to both ends of the first main member  11  and the second main member  12  respectively. The hanging arms  13  at the first main member  11  are disposed to be opposite to those at the second main member  12  in a way of the inner sides of the hanging arms  13  at the first main member  11  facing the inner sides of the hanging arms  13  at the second main member  12 . The respective hanging arm  13  provides a recess at two opposite lateral sides to catch two lateral sides of a third main member  14 . At least a screw rod  15  penetrates the respective hanging arm  13 , the first main member  11  and the second main member  12  such that both ends of the screw rod extend outward the first and second main member  11 ,  12  for a space between the two main members  11 ,  12  being capable of being adjusted and set with a nut  15  fastening to both ends of the screw rod. 
     The first main member  11  at least has a threaded hole  111  and a press element  17  corresponds the threaded hole  111 . The press element has a knob  171  and a threaded stem  172 . The threaded stem  172  engages with the threaded hole  111  and passes through the threaded hole  111 . An elastic element  173  surrounds the threaded stem  172  and a touch block  174  connects with an end of the threaded stem  172 . 
     At least a work piece  18 , which can be a radiator, is disposed between the first main member  11  and the second main member  12 . When the press element  17  is turned with the knob  171  thereof, the threaded stem  172  urges the touch block  174  toward the second main member  12  to press the plated work piece  18 . In this way, the work piece  18  is held between the first and second main members  11 ,  12  temporarily to expose the plated zone of the work piece  18 . 
     The elastic element  173  is capable of adjusting pressure of the touch block  174  against the work piece  18  to prevent the work piece  18  from being hurt with excessive pressure while the threaded stem  172  urging the touch block  174 . 
     Referring to  FIGS. 4 and 5 , the fixture is placed at a plating tank  19  with the third main member  14  supported by two opposite sides of the plating tank  19  for the plated zone of the work piece  18  being emerged in the liquid contained in the plating tank  19 . 
     Referring to  FIGS. 6 and 7 , another type fixture is illustrated. The second type fixture includes a main member  21 , an arm  211  extending from two ends of the main member  21 , a plurality of slits  213  at a lateral side  212  of the main member  21 , a plurality of through holes  214  passing through the lateral side  212  and a plurality of threaded connecting elements  22  corresponding to the through holes  214 . Each of the threaded connecting elements  22  has a threaded rod part being sleeved with an elastic element  23  and a press plate  24  sequentially. The threaded rod part penetrates through the through holes  214  of the main member  21  from the lateral side with slits  213  and a nut  25  fastens the threaded rod part at a lateral side opposite to the lateral side with slits  213 . 
     At least a work piece  26  such as cooling fin is inserted into the slits  213  individually and the press plate  24  presses the work piece  26  with an elastic urging force of the elastic element  23  once the respective threaded connecting element  22  is fastened with the nut  25 . Hence, the work piece  26  is held to the main member  21  temporarily in a way of the plated zone on the surface of the work piece exposes. 
     Referring to  FIGS. 8 and 9 , the preceding fixture is attached to a plating tank  27  and two opposite lateral walls of the plating tank  27  at the top thereof are attached with a support base  28  by means of an adjustable screw  29  passing through the support base  29  and the plating tank  27 . The support base  28  has extension part  281  disposed in the plating tank  27  to allow two ends of the main member  21  are supported by the extension part  281  such that the main member  21  is capable of retaining at the top of the plating tank  27  and the plated zone on the surface of the work piece  26  is capable of being immerged into liquid in the plating tank  27 . 
     It is appreciated that advantages of a method for a surface being plated locally according to the present invention is that the method of the present invention is capable of producing a uniform and good looking strip shaped zinc layer and nickel plated surface without wasting zinc solution and nickel solution substantively. 
     While the invention has been described with referencing to preferred embodiments thereof, it is to be understood that modifications or variations may be easily made without departing from the spirit of this invention, which is defined by the appended claims.