ELECTROCHEMICAL TREATMENT SYSTEM

Abstract

An electrochemical treatment system includes a treatment fluid supply manifold, a fluid return manifold, and an electrode section connected to the treatment fluid supply manifold. A plurality of treatment fluid supply ports feed fluid through or across the electrode and a plurality of fluid return ports proximate the treatment fluid supply ports are connected to the fluid return manifold. A porous pad is coupled to the electrode section for contacting a substrate to be treated and receives the treatment fluid via the plurality of treatment fluid supply ports. The plurality of fluid return ports remove spent and excess treatment fluid and gases from the substrate, the surrounding air, and the porous pad.

Claims

1. An electrochemical treatment system comprising: a housing including: a treatment fluid supply manifold, a fluid return manifold, an electrode section connected to the treatment fluid supply manifold, a plurality of treatment fluid supply ports that feed fluid through or across the electrode, and a plurality of fluid return ports proximate the treatment fluid supply ports and connected to the fluid return manifold; and a porous pad coupled to the electrode section for contacting a substrate to be treated and receiving the treatment fluid via the plurality of treatment fluid supply ports while the plurality of fluid return ports remove spent and excess treatment fluid and gases from the substrate, the surrounding air, and the porous pad.

2. The system of claim 1 in which the treatment fluid is an electrolyte.

3. The system of claim 1 further including a treatment fluid reservoir coupled to the treatment fluid supply manifold via a first pump.

4. The system of claim 3 further including a return flow reservoir coupled to the fluid return manifold via a second pump.

5. The system of claim 4 further including a controller automatically operating the first pump and the second pump at rates which fully disperse the treatment fluid throughout the pad while limiting leakage of treatment fluid from the pad.

6. The system of claim 1 further including a power supply electrically interconnected between the electrode and the substrate.

7. The system of claim 1 in which the treatment fluid supply manifold includes linear channels each over an array of fluid supply ports and the return manifold includes linear channels each over an array of fluid return ports.

8. The system of claim 7 in which the fluid supply manifold linear channels alternate with the return fluid manifold linear channels.

9. The system of claim 7 in which the array of fluid supply ports is a 1 by n array where n is greater than 1.

10. The system of claim 7 in which the return fluid ports are in a 1 by n array where n is greater than 1.

11. The system of claim 7 in which the fluid supply manifold further includes a duct interconnecting the linear channels over the array of fluid supply ports.

12. The system of claim 7 in which the return fluid manifold further includes a duct interconnecting the linear channels over the array of return fluid ports.

13. The system of claim 1 in which the electrode section further includes a peripheral fluid return and the pad lies internal to the peripheral fluid return.

14. The system of claim 13 in which the electrode further includes a peripheral fluid return manifold coupled to the peripheral fluid ports.

15. The system of claim 1 in which the housing includes an internal wall separating the housing into a treatment fluid supply chamber and a return fluid chamber.

16. The system of claim 15 in which the fluid supply chamber is between the wall and the electrode bottom section, the fluid supply ports in communication with the fluid supply chamber.

17. The system of claim 16 in which the fluid supply manifold includes the fluid supply chamber and a conduit extending from the fluid supply chamber through the wall.

18. The system of claim 16 in which the fluid return manifold includes the fluid return chamber and conduits extending through the internal wall to the fluid return ports in the bottom electrode section.

19. The system of claim of claim 1 in which the fluid supply manifold includes a first plenum and the fluid return manifold includes a second plenum nestled with the first plenum.

20. The system of claim 1 in which the pad includes non-woven fibers in a three-dimensional web.

21. The system of claim 1 in which there are first and second treatment fluid manifolds each connected to a sub plurality of treatment fluid supply ports and each connected via a pump to a different treatment fluid reservoir.

22. The system of claim 1 in which there are one or more treatment cells, constructed so that each cell may be operated independently, or together with any other cell, each cell comprising an fluid supply manifold, a fluid return manifold, an electrode, and a plurality of fluid supply ports and fluid return ports.

23. The system of claim 22 in which the electrode is flexible, allowing the system to maintain contact with a curved surface.

24. The system of claim 23 in which the electrode is made of wires, grids, meshes, fibers, conductive polymers, or other flexible materials.

25. A method of electrochemically treating a substrate, the method comprising: contacting the substrate with an electrode fitted with a porous pad; driving a treatment fluid through supply ports in the electrode and to multiple locations of the porous pad; and automatically driving spent and excess treatment fluid and gases from multiple locations of the porous pad through return ports in the electrode at a rate which limits treatment fluid leakage from the pad while urging the treatment fluid to fully disperse throughout the extent of the pad.

26. The method of claim 22 in which the treatment fluid is an electrolyte solution.

27. The method of claim 22 further including pumping the treatment fluid from a reservoir to the electrode.

28. The method of claim 24 further including pumping the spent and excess treatment fluid from the pad.

29. The method of claim 22 further including connecting a power supply between the electrode and the substrate.

30. The method of claim 22 in which the pad includes non-woven fibers in a three-dimensional web.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0041] Other objects, features and advantages will occur to those skilled in the art from the following description of a preferred embodiment and the accompanying drawings, in which:

[0042] FIG. 1 is a schematic view of one particular version of the whole selective plating/anodizing system;

[0043] FIG. 2 is a schematic view of one version of the electrode with an integrated single supply channel system and an integrated single return flow channel system;

[0044] FIG. 3 is a view showing rectangular return flow ports and circular supply flow ports shown in electrode face;

[0045] FIG. 4 is a schematic view of an alternative version of the electrode;

[0046] FIG. 5 is a schematic view of an integrated electrode design with one supply flow channel system, one return flow (exhausting) channel system and one peripheral channel system;

[0047] FIG. 6 is a schematic view of FIG. 5, seen from the opposite side;

[0048] FIG. 7 is a schematic view of an integrated electrode design with one supply flow channel system, one return flow (exhausting) channel system and one peripheral channel system;

[0049] FIG. 8 is a schematic view of an integrated electrode design with one supply flow channel system, one return flow (exhausting) channel system and one peripheral channel system;

[0050] FIG. 9 is a schematic view of an electrode design showing integrated concentric supply flow and return flow channel systems;

[0051] FIG. 10 is another schematic view of an embodiment using concentric supply flow and return flow channel systems;

[0052] FIG. 11 is a block diagram depicting the primary components associated with an example of a treatment system and method; and

[0053] FIG. 12 is a schematic showing the structure and cross section of an embodiment for processing long objects, incorporating a series of cells, each comprising a series of holes or slots as electrolyte supply ports and return flow ports. Such a structure could be manufactured from rigid or flexible materials to accommodate flat or curved surfaces.

DETAILED DESCRIPTION OF THE INVENTION

[0054] Aside from the preferred embodiment or embodiments disclosed below, this invention is capable of other embodiments and of being practiced or being carried out in various ways. Thus, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. If only one embodiment is described herein, the claims hereof are not to be limited to that embodiment. Moreover, the claims hereof are not to be read restrictively unless there is clear and convincing evidence manifesting a certain exclusion, restriction, or disclaimer.

[0055] The present invention is directed to scalable device for electrochemical treatment of a surface in any orientation

[0056] In one version, the device of FIG. 1 includes one or more supply fluid reservoir(s) 1, one or more return fluid reservoir(s) 2, solid electrode 3a with an integrated plurality of supply fluid channel systems 3b and return flow channel systems 3c, porous media pad 4, a power supply 5, pumps 6a and 6b, controlled by controller 6c, tubing 7c and 7a. Controller 6c may be a microprocessor, microcontroller, computer subsystem, or the like. The supply fluid reservoir 1 is connected to a pump 6a via tubing 7a. The pump 6a motivates the supply fluid from the supply fluid reservoir 1 through tubing 7a to the supply fluid channel systems integrated into the solid electrode 3a. The electrode supply fluid channels exit through numerous electrolyte ports 3b on the face(s) of the solid electrode 3a adjacent to the porous pad 4 enabling fluid flow into and through the porous pad 4 towards a substrate 8 being treated. Also, adjacent to the porous media pad 4 and on the electrode surface, there are preferably numerous electrolyte suction ports 3c connecting to the return fluid channel systems integrated within the same solid electrode 3a. These return fluid channel systems are manifolded into collection point 9 on surface(s) of the solid electrode 3a and are then connected through tubes 7b that connect to the return fluid reservoir(s) 2 via pump 6b which provide the suction to motivate the return fluids which comprise a mixture of excess supply fluids and ambient gases 10 to the return fluid reservoir 2.

[0057] When in a plating or anodizing mode or employing processes requiring the supply of current, electrode 3a is electrically connected to one terminal of the activated power supply 5. Substrate 8 is electrically connected to the other terminal of the activated power supply 5.

[0058] The tool is then placed in a position, touching the surface to be treated 8 and moved relative to the surface, by hand or with help of automation, over the substrate 8, thereby completing an electrical circuit from the power supply 5 through the electrode 3a and fluid in the porous pad 4 to the substrate 8 and back to the power supply 5. Pad 4 may be structure of fibers (e.g., non-woven) in a three-dimensional web, see, for example, U.S. Pat. No. 2,958,593 incorporated herein by this reference. Sponges, scouring pads, and the like, may also serve as the pad.

[0059] Fluid is supplied from a reservoir 1 such as a bottle, via pump 6a to the plumbed fluid supply system of channels within the integrated electrode 3a. Within the electrode, a system or systems of channels distribute the supply fluid to a matrix of fluid supply ports 3b on the electrode face or faces which are adjacent and connected to a porous media pad 4. The supply fluid distributes through the porous media pad 4 and wets the substrate 8 enough for the electrochemical treatment. Excess fluid is simultaneously collected and sucked through the porous pad 4 into a separate system of fluid return channels which are in turn plumbed to return tubing connecting to a return fluid reservoir 2 or bottle via a pump 6b. The balance of fluid supply and fluid return may be controlled by the controller 6c. The integrated electrode structure 3a is connected via a power supply 5 to the substrate to be treated 8, in this way the electrical circuit can be completed and the supply fluid or electrolyte can then react and electroplate onto the substrate being treated 8 or indeed anodize the substrate to be treated 8 if the polarity of the power supply 5 is changed. This whole system can indeed be operated without the power supply 5 if for example, the system is used for a rinsing step.

[0060] FIGS. 2-3 show examples of the fluid supply connection 11 and fluid return connection 12 in housing 50 to an integrated electrode 13 with a fluid supply channel system 14 and a fluid return channel system 15. Electrode 13 includes fluid supply ports 16 and the fluid return or collection ports 17 on the bottom face of the integrated electrode structure. The fluid supply manifold includes linear channels 14 connect to duct 52 and the fluid return manifold includes linear channels 15 connected to duct 54. Channels 14 and 15 alternate with each other.

[0061] FIG. 4 shows an alternative electrode design with two separate fluid supply channel systems 18a and 18b as well as a separate fluid return channel system 19.

[0062] FIG. 5 shows a particular embodiment with three separate fluid supply channel systems integrated into the electrode. The fluid supply 20 is connected to one channel system, the fluid return 21 is drawn from another channel system and there is an additional return 22 drawn or sucked from a peripheral slot 25, FIG. 6. Three separate fluid flow channel systems can be integrated into the electrode. A pumping system motivates supply fluid to the supply fluid channel system 23. In this particular design, there are two fluid return systems, one system connected to a pump in order to collect the flow from a matrix of ports 24 on the face of the electrode and another, peripheral system 25 connected to another pump allowing collection of fluid from the periphery. Alternatively, the peripheral system could be operated in reverse, to supply another inlet fluid or an inerting gas.

[0063] FIG. 7 shows a section view illustrating the detail of the integrated electrode design introduced and presented in FIG. 5. Using a construction of a system of plenums 26a, 26b and hollow pillars or conduits 27 it is possible to manufacturer (3D additive techniques for example) a structure that can keep the fluid channel systems separate. This view shows in particular how the supply fluid delivered though conduit 28 flows into the lower plenum 26a and out of the fluid supply ports 29 to the porous media (not shown).

[0064] Housing 50 includes internal wall 60 separating the housing into treatment fluid supply chamber 62 and fluid return chamber 64. The fluid supply manifold thus includes chamber 62 and conduit 28 through wall 60 and extending out of housing 50. Fluid in chamber 62 flows through fluid supply ports 29. The return flow manifold includes chamber 64 and conduits 27 extending through wall 60 to the electrode return ports 35, FIG. 8.

[0065] Furthermore, it is possible to see another return flow system where the fluid can be collected from a periphery slot 31 on the electrode active face 32 and directed through a separate channel system to a further collection point 33, in this case, on the top (or back) face of the electrode 34.

[0066] FIG. 8, another view of FIG. 5, shows in particular how the return fluid is collected from the porous media (not shown) via a system of ports 35 into a separate, upper plenum 36, via hollow pillars 37. This view shows in particular how the fluid collected from the porous media (not shown) is directed to an upper plenum and then collected through the fluid return collection 38 and directed to the pump.

[0067] FIG. 9 shows an alternative structure for the manifolds. In this example the supply fluid 39 flows through a plenum to an inner circular arrangement of ports towards the porous media (not shown) and the return fluid 40 is collected from an outer, circular plenum 72 collection of ports arranged concentric to the supply fluid ports. Similarly, serpentine and spiral arrangements can be constructed. Plenums 70 and 72 are nested as shown.

[0068] FIG. 10 shows another view of FIG. 9, where the supply fluid 41 is directed to the porous media (not shown) through an inner circular arrangement of ports and the return fluid 42 is collected through a circular arrangement of ports arranged concentric to the supply fluid ports.

[0069] In one embodiment, FIG. 11, an electrochemical treatment system housing 50, includes a treatment fluid supply manifold 80 and a fluid return manifold 82 and a bottom electrode section 13. There are a plurality of treatment fluid supply ports 16 in the bottom electrode section connected to the treatment fluid supply manifold 80 and a plurality of fluid return ports 17 in the bottom electrode section proximate the treatment fluid supply ports and connected to the fluid return manifold 82. A porous pad 10 is coupled to the bottom electrode section 13 for contacting a substrate to be treated and receiving the treatment fluid via the plurality of treatment fluid supply ports while the plurality of fluid return ports remove spent and excess treatment fluid and gases from the substrate and the porous pad.

[0070] A treatment fluid reservoir 84 coupled to the treatment fluid supply manifold 80 via a first pump P.sub.1. A return fluid reservoir 86 is coupled to the fluid return manifold 82 via a second pump P.sub.2. Controller 88 may be programmed to automatically operate the first pump Pt and the second pump P.sub.2 at rates which limit leakage of treatment fluid from the pad 10 while urging the treatment fluid to fully disperse throughout the pad 10.

[0071] A method of electrochemically treating a substrate features contacting the substrate with an electrode 13 fitted with a porous pad 10. A treatment fluid is driven through supply ports 16 in the electrode and to multiple locations of the porous pad. Spent and excess treatment fluid and gases are driven from multiple locations of the porous pad through return ports 17 in electrode 13 at a rate which limits electrolyte leakage from the pad 10 while urging the treatment fluid to fully disperse throughout the extent of the pad.

[0072] There may be a ratio of one supply port for several surrounding return ports, or supply and return tubes of different diameters, or pumps that feed electrolyte and exhaust electrolyte and air at different rates. The controller can be programmed to operate the pumps based on several factors such as the number and size and spacing of the supply ports and return ports, the size, material, and the porosity of the pad, and the viscosity of the treatment fluid (e.g., an electrolyte, rinsing water, ionic salts, and the like).

[0073] FIG. 12 shows another design intended for coating large areas. This design comprises one or more cells or sections that may be separated by intercell boundaries 95 and may be operated independently or simultaneously. The fluid is pumped into the electrode 90 via the supply tube 92. It is dispersed into the electrolyte pad 97 via an array of supply ports 94, and air plus electrolyte is pumped out via return slots or holes 96 connected to the return manifold 91 and from there to fluid return tubes 93. For coating flat areas, the cells may be flat and rigid, while for curved surfaces the cells may be constructed of flexible material, for example, the electrode made from wire, fiber, mesh, conductive polymer, or other flexible, electrical conductors.

[0074] A typical anodizing treatment using an electrolyte may employ a pad 4″ by 4″ which can be moved over a part to be treated manually, robotically (e.g., using a robot arm), or using a CNC machine or, the pad and electrolyte can be held stationary and the part rotated or moved relative to the pad and electrolyte.

[0075] The balance of the fluid supply flows and fluid return flows can be important to the operation of the non-drip system. The balance of the fluid flows may depend on many parameters, such as the supply flow rates, the return flow rates, viscosity of the fluids, temperature, porosity of the porous media, capillarity forces, pressure drop through the flow channels, the proximate arrangement of the supply flow and return flow ports on the electrode face, and the precise geometry and routes of the fluid flow channel systems within the electrode. Testing the effect of each of the parameters mentioned above with physical prototypes would be time consuming, and there is no guarantee that an appropriate design can be achieve with such a “hit and miss”, i.e. Edisonian approach. A more effective engineering procedure is to create a virtual prototype using Computational Fluid Dynamics (CFD) where one can quantitatively assess the impact of each of these parameters on the final design. Therefore, one can size and optimize the precise channel system dimensions and routing in order to calculate the pump rates required for the operational balance of supply flows and return flows to eliminate drippage. Unfortunately, most of the CFD models needed for these complex phenomena do not take into consideration the full set of forces, for example the capillary force. There may be different combinations of parameters according to the process. For example, the optimum geometry and fluid flow settings for an anodizing process may differ from the optimum geometry and settings for a plating process. However, these optimum parameters can be calculated, upfront with CFD techniques. The electrode can then be manufactured and a pump controller programmed with the necessary logic for that particular process.

[0076] Although specific features of the invention are shown in some drawings and not in others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention. The words “including”, “comprising”, “having”, and “with” as used herein are to be interpreted broadly and comprehensively and are not limited to any physical interconnection. Moreover, any embodiments disclosed in the subject application are not to be taken as the only possible embodiments. Other embodiments will occur to those skilled in the art and are within the following claims.

[0077] In addition, any amendment presented during the prosecution of the patent application for this patent is not a disclaimer of any claim element presented in the application as filed: those skilled in the art cannot reasonably be expected to draft a claim that would literally encompass all possible equivalents, many equivalents will be unforeseeable at the time of the amendment and are beyond a fair interpretation of what is to be surrendered (if anything), the rationale underlying the amendment may bear no more than a tangential relation to many equivalents, and/or there are many other reasons the applicant cannot be expected to describe certain insubstantial substitutes for any claim element amended.