U.S. patent application number 12/784697 was filed with the patent office on 2011-11-24 for method and apparatus for anodizing objects.
This patent application is currently assigned to Pioneer Metal Finishing. Invention is credited to Karsten V. Nielsen, Scott S. Turner.
Application Number | 20110284385 12/784697 |
Document ID | / |
Family ID | 44482480 |
Filed Date | 2011-11-24 |
United States Patent
Application |
20110284385 |
Kind Code |
A1 |
Turner; Scott S. ; et
al. |
November 24, 2011 |
Method and Apparatus For Anodizing Objects
Abstract
A method and apparatus for electrolytically treating a surface
of a component includes a reaction chamber, a transport chamber and
a fluid return path. The reaction chamber is adapted for placing at
least a portion of the component therein, and holds a reaction
fluid. Fluid enters the reaction chamber through a plurality of
inlets. Each inlet directs the fluid toward the component at one or
more non-zero vertical angles, and at one or more non-zero
horizontal angles. The reaction chamber is a fixture having a cover
with an underside shaped to direct the fluid to the surface of the
component, such as by having a plurality of slopes. The inlets are
through a material that is electrically non-conductive, such as
ceramic, plastic, PVC, and fiber reinforced plastic, and/or the
fixture further includes a titanium cathode ring that can be
vertically adjacent the non-conductive material.
Inventors: |
Turner; Scott S.; (Green
Bay, WI) ; Nielsen; Karsten V.; (DePere, WI) |
Assignee: |
Pioneer Metal Finishing
Green Bay
WI
|
Family ID: |
44482480 |
Appl. No.: |
12/784697 |
Filed: |
May 21, 2010 |
Current U.S.
Class: |
205/80 ;
204/275.1 |
Current CPC
Class: |
C25D 11/02 20130101;
C25D 11/005 20130101; C25D 17/02 20130101; C25D 5/08 20130101 |
Class at
Publication: |
205/80 ;
204/275.1 |
International
Class: |
C25D 5/00 20060101
C25D005/00; C25D 17/00 20060101 C25D017/00 |
Claims
1. An apparatus for electrolytically treating a surface of a
component comprising: a reaction chamber, adapted for placing at
least a portion of the component therein, and for holding a
reaction fluid; a transport chamber in fluid communication with the
reaction chamber, wherein the fluid enters the reaction chamber
from the transport chamber through a plurality of inlets directed
toward the component, wherein each of the plurality of inlets is
disposed to direct the fluid toward the component at least one
non-zero vertical angle; and a fluid return path, wherein the fluid
returns from the reaction chamber to the transport chamber.
2. The apparatus of claim 1, wherein the at least one non-zero
vertical angles is at least two non-zero vertical angles.
3. The apparatus of claim 2, wherein at least a first of the at
least two non-zero vertical angles is greater than zero and at
least a second of the at least two non-zero vertical angles is less
than zero.
4. The apparatus of claim 1, wherein each of the plurality of
inlets is further disposed to direct the fluid toward the component
at least one non-zero horizontal angle.
5. The apparatus of claim 4, wherein the at least one non-zero
horizontal angle is at least two non-zero horizontal angles.
6. The apparatus of claim 1, wherein each of the plurality of
inlets is further disposed to direct the fluid toward the component
at least one non-zero horizontal angle.
7. The apparatus of claim 1, wherein the reaction chamber is a
fixture having a cover over the reaction chamber, and the cover has
an underside shaped to direct the fluid entering the reaction
chamber through the plurality of inlets to the surface of the
component.
8. The apparatus of claim 7, wherein the cover underside has a
plurality of slopes.
9. The apparatus of claim 7, wherein the plurality of inlets and
the cover underside cooperate to refresh the fluid at the
surface.
10. The apparatus of claim 7, wherein the plurality of inlets and
the cover underside cooperate to cause the fluid to remove heat
from the surface of the component.
11. The apparatus of claim 7, wherein the plurality of inlets are
through a first material that is electrically non-conductive.
12. The apparatus of claim 11, wherein the first material is
comprised of at least one of ceramic, plastic, PVC, and fiber
reinforced plastic
13. The apparatus of claim 11, wherein the plurality of inlets are
in the fixture, and the fixture further includes a titanium cathode
ring.
14. The apparatus of claim 13, wherein the titanium cathode ring is
vertically adjacent the first material.
15. The apparatus of claim 1, wherein the plurality of inlets are
through a first material that is electrically non-conductive and
wherein the reaction chamber is a fixture and the plurality of
inlets are through the fixture, and the fixture further includes a
titanium cathode ring.
16. The apparatus of claim 15, wherein the titanium cathode ring is
vertically adjacent the first material.
17. A fixture for anodizing a component, comprising, a reaction
chamber with a plurality of inlets, wherein each of the plurality
of inlets is disposed to direct an electrolyte toward the component
at least one non-zero vertical angle.
18. The fixture claim 17, wherein the at least one non-zero
vertical angles is at least two non-zero vertical angles.
19. The fixture of claim 18, wherein at least a first of the at
least two non-zero vertical angles is greater than zero and at
least a second of the at least two non-zero vertical angles is less
than zero.
20. The fixture of claim 19, wherein each of the plurality of
inlets is further disposed to direct the fluid toward the component
at least one non-zero horizontal angle.
21. The fixture of claim 20, wherein the at least one non-zero
horizontal angle is at least two non-zero horizontal angles.
22. The fixture of claim 20, wherein the fixture includes a cover
over the reaction chamber, and the cover has an underside disposed
to direct the electrolyte to a reaction surface of the
component.
23. The fixture of claim 22, wherein the plurality of inlets and
the cover underside cooperate to refresh the electrolyte at the
reaction surface.
24. The fixture of claim 23, wherein the plurality of inlets and
the cover underside cooperate to cause the electrolyte to remove
heat from the reaction surface.
25. The fixture of claim 24, wherein the cover underside has a
plurality of slopes.
26. The fixture of claim 22, wherein the plurality of inlets are
through a first material that is electrically non-conductive.
27. The fixture of claim 26, wherein the first material is
comprised of at least one of ceramic, plastic, PVC, and fiber
reinforced plastic, and wherein the fixture further includes a
titanium cathode ring.
28. The fixture of claim 25, wherein the titanium cathode ring is
vertically adjacent the first material.
29. A method for electrolytically treating a component comprising,
directing a reaction fluid toward the component along a plurality
of paths, wherein each of the plurality of paths is at one of at
least one non-zero vertical angle.
30. The method of claim 30, wherein directing a reaction fluid
toward the component along a plurality of paths at one of at least
one non-zero vertical angle, includes directing a reaction fluid
toward the component along a plurality of paths, wherein each of
the plurality of paths is at one of at least two non-zero vertical
angles.
31. The method of claim 30, wherein at least a first of the at
least two non-zero vertical angles is greater than zero and at
least a second of the at least two non-zero vertical angles is less
than zero.
32. The method of claim 30, wherein each of the plurality of paths
is at at least one non-zero horizontal angle.
33. The method of claim 32, wherein the at least one non-zero
horizontal angle is at least two non-zero horizontal angles.
34. The method of claim 33 further comprising refreshing the fluid
at the surface.
35. The method of claim 34 further comprising, remove heat from the
surface of the component.
36. The method of claim 32, wherein directing the reaction fluid
toward the component along a plurality of paths includes directing
the reaction fluid through a first material that is electrically
non-conductive.
37. The method of claim 32, wherein directing the reaction fluid
toward the component along a plurality of paths includes directing
the reaction fluid through a first material that is electrically
non-conductive and vertically adjacent a cathode ring.
38. The method of claim 32, wherein directing the reaction fluid
toward the component along a plurality of paths includes directing
the reaction fluid through a first material that is electrically
non-conductive and vertically adjacent a titanium cathode ring.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to the art of
electrolytic formation of coatings on metallic parts. More
specifically, it relates to electrolytic formation of a coating on
a metallic substrate by cathodic deposition of dissolved metallic
ions in the reaction medium (electrolyte) onto the metallic
substrate (cathode), or anodic conversion of the metallic substrate
(anode) into an adherent ceramic coating (oxide film).
BACKGROUND OF THE INVENTION
[0002] It is well known that many metallic components or parts need
a final surface treatment. Such a surface treatment increases
functionality and the lifetime of the part by improving one or more
properties of the part, such as heat resistance, corrosion
protection, wear resistance, hardness, electrical conductivity,
lubricity or by simply increasing the cosmetic value.
[0003] One example of a part that is typically surface treated is
the head of aluminum pistons used in combustion engines. (As used
herein an aluminum component is a component at least partially
comprising aluminum, including aluminum alloys.) Such piston heads
are in contact with the combustion zone, and thus exposed to
relatively hot gases. The aluminum is subjected to high internal
stresses, which may result in deformation or changes in the
metallurgical structure, and may negatively influence the
functionality and lifetime of the parts. It is well known that
formation of an anodic oxide coating (anodizing) reduces the risk
of aluminum pistons performing unsatisfactorily. Thus, many
aluminum piston heads are anodized.
[0004] There is a drawback to anodizing piston heads. Conventional
anodizing with direct current or voltage, increases the surface
roughness of the initial aluminum surface by applying an anodic
coating. The amount of VOC (Volatile Organic Compounds) in the
exhaust of a combustion engine is correlated with the surface
finish of the anodized aluminum piston: higher surface roughness
reduces the efficiency of the combustion, because a greater
proportion of organic compounds can be trapped in micro cavities
more easily. Therefore, a smooth surface is required, which may not
always be provided by anodization.
[0005] Conventional anodizing includes subjecting the aluminum to
an acid electrolyte, typically composed of sulfuric acid or
electrolyte mixed with sulfuric and oxalic acid. Higher
concentrations and temperature usually decrease the formation rate
significantly. Also, the formation voltage decreases with higher
temperature, which adversely affects the compactness and the
technical properties of the oxide film.
[0006] Performing anodizing processes at a (relatively) low
temperature and fairly high current density increases the
compactness and technical quality of the coating performance (high
hardness and wear resistance). The anodization produces a
significant amount of heat. Heat is the result of the exothermic
nature of the anodizing of aluminum, and the resistance of the
aluminum toward anodizing.
[0007] The electrolyte is acidic, and thus chemically dissolves the
aluminum oxide. Thus, the net formation of the coating (aluminum
oxide) depends on the balance between electrolytic conversion of
aluminum into aluminum oxide and chemical dissolution of the formed
aluminum oxide. The rate of chemical dissolution increases with
heat. Thus, the total production of heat influences this balance
and the final quality of the anodic coating. Heat should be
dispersed from areas of production toward the bulk solution at a
rate that prevents excess heating of the electrolytic near the
aluminum part. If the balance between formation and dissolution is
not properly struck, and dissolution is favored, the oxide layer
may develop holes, exposing the alloy to the electrolyte.
[0008] Heat produced at the aluminum surface is dispersed by air
agitation or mechanically stirring of the electrolyte in which the
oxidation of aluminum is taking place, in the prior art, to help
reach the desired balance. Another way of dispersing the heat is by
spraying the electrolyte toward the aluminum surface (U.S. Pat. No.
5,534,126 and U.S. Pat. No. 5,032,244). The electrolyte is sprayed
toward the aluminum surface at an angle of 90 degrees, moving heat
toward the areas of production, and then symmetrically dispersed
away from the aluminum surface. Another way to disperse heat is to
pump the electrolyte over the aluminum substrate (U.S. Pat. No.
5,173,161). The electrolyte is moved parallel to the aluminum
surface, moving heat from the lower part of the aluminum substrate
over the entire surface before it is finally dispersed away from
the aluminum surface.
[0009] U.S. Pat. No. 6,126,808, hereby incorporated by reference,
is a significant advance over the prior art and teaches to spray
the reaction medium toward the metallic substrate (component)
through holes in the counter electrode (cathode) at a horizontal
angle of between 15 and 90 degrees, and preferably between 60 and
70 degrees. Horizontal angle, as used herein, includes the angle,
in a horizontal plane, relative to the shortest horizontal distance
to a component, and a zero horizontal angle is along the horizontal
line that is the shortest distance to the component.
[0010] The system provides for flow of the reaction medium from a
bulk solution below the container through the reaction chamber and
back into the reservoir. Because the reaction medium moves toward
the working electrode at a horizontal angle, heat and reaction
products may be dissipated away from the working electrode. The
electrolyte is stored and chilled to an appropriate process
temperature ranging from -10 degrees C. to +40 degrees C. This
system was a substantial improvement over the prior art. However,
dissolved metals from the process can plate the holes in the
counter electrode (cathode), which can lead to clogging unless
cleaning is performed.
[0011] An anodizing method and apparatus that further reduce
processing time with high formation potentials and minimal handling
to obtain coatings of desirable quality and consistency is
desirable. The process and apparatus will preferably lessen
production costs and have a closed loop process design that reduces
the impact of the electrolyte on internal and external
environments. The process will preferably further remove heat from
near the component being anodized, and avoid clogging of nozzles
through which the reaction fluid flows.
SUMMARY OF THE PRESENT INVENTION
[0012] According to a first aspect of the invention an apparatus
for electrolytically treating a surface of a component includes a
reaction chamber, a transport chamber and a fluid return path. The
reaction chamber is adapted for placing at least a portion of the
component therein, and holds a reaction fluid. The transport
chamber is in fluid communication with the reaction chamber. Fluid
enters the reaction chamber from the transport chamber through a
plurality of inlets directed toward the component. Each of the
inlets is disposed to direct the fluid toward the component at
least one non-zero vertical angle. The fluid returns from the
reaction chamber to the transport chamber via the fluid return
path.
[0013] According to a second aspect of the invention a fixture for
anodizing a component includes a reaction chamber with a plurality
of inlets. Each of the inlets directs the electrolyte toward the
component at least one non-zero vertical angle.
[0014] According to a third aspect of the invention a method for
electrolytically treating a component includes directing a reaction
fluid toward the component along a plurality of paths. Each path is
at one of at least one non-zero vertical angle.
[0015] The at least one non-zero vertical angle is at least two
non-zero vertical angles, greater than and/or less than zero in
various alternatives.
[0016] The plurality of inlets direct the fluid toward the
component at least one non-zero horizontal angle, or at least two
non-zero horizontal angles, greater than and/or less than zero in
other alternatives.
[0017] The reaction chamber is a fixture having a cover with an
underside shaped to direct the fluid to the surface of the
component, such as by having a plurality of slopes in other
embodiments.
[0018] The plurality of inlets and the cover underside cooperate to
refresh the fluid at the surface, and/or cause the fluid to remove
heat from the surface of the component in other alternatives.
[0019] The inlets are through a material that is electrically
non-conductive, such as ceramic, plastic, PVC, and fiber reinforced
plastic, and/or the fixture further includes a titanium cathode
ring that can be vertically adjacent the non-conductive material in
various alternatives.
[0020] Other principal features and advantages of the invention
will become apparent to those skilled in the art upon review of the
following drawings, the detailed description and the appended
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a block diagram of a general method implementing
the present invention;
[0022] FIG. 2 is a schematic sectional view of process container
implementing the present invention;
[0023] FIG. 3 is an angle sectional view of a counter electrode in
accordance with the preferred embodiment;
[0024] FIG. 4 is a perspective view of a counter electrode in
accordance with the preferred embodiment;
[0025] FIG. 5 is vertical cross section of a working electrode
mounted in a mounting fixture, in accordance with the preferred
embodiment;
[0026] Before explaining at least one embodiment of the invention
in detail it is to be understood that the invention is not limited
in its application to the details of construction and the
arrangement of the components set forth in the following
description or illustrated in the drawings. The invention is
capable of other embodiments or of being practiced or carried out
in various ways. Also, it is to be understood that the phraseology
and terminology employed herein is for the purpose of description
and should not be regarded as limiting. Like reference numerals are
used to indicate like components.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] While the present invention will be illustrated with
reference to a particular system and method for anodizing an
aluminum part with a particular fixture, it should be understood at
the outset that the invention can also be implemented with other
systems and methods and used to anodize other parts comprising
other materials held in other fixtures.
[0028] The process and apparatus described herein is generally
consistent with that of prior art U.S. Pat. No. 6,126,808, but with
changes that are described below. The general process and system
are shown by the block diagram of FIG. 1. Anodizing occurs in a
process container 100 (described in more detail later). A working
electrode 102 (i.e., the part to be anodized) is placed in a
reaction container 104, which is part of container 100. After
anodizing component or part 102 is moved to a rinsing tank 110,
where the working electrode is rinsed with water pumped from a
rinse reservoir 112 by a pump 114 into a rinse chamber 116, through
a set of spray nozzles 118. The rinse water leaves the rinse
chamber 116 through a rinse outlet 119 and returns to the rinse
reservoir 112. Working electrode or part 102 is mechanically held
in position during the rinse. After rinsing, working electrode 102
is transferred to a drying container 120, where it is dried with
hot air from a heater 122, which is pumped into the drying
container 120 through several drying inlets 124. Component, as used
herein, includes the device or object which is being treated or
anodized.
[0029] Alternatives include performing multiple steps (such as
anodizing and rinsing) in a single container or providing a station
(following drying container 120, e.g.) that scan the component as a
quality control measure. The scanning may be automatically
performed using known techniques such as neural network
analysis.
[0030] Referring now to FIG. 2, a schematic of a section of process
container 100 and related components is shown, including an outer
circular transport chamber 201 and inner reaction container 104.
The reaction medium (electrolytic solution) is transported from a
medium reservoir 202, located below process container 100 and in
fluid communication therewith, by a pressure pump 203 into
transportation chamber 201 through several inlet channels 205.
Alternatives include other shaped chambers, as well as the inlets
and outlets being in different locations. Fluid communication, as
used herein, includes a path or connection through which fluid can
flow from one location or container to another. Reaction chamber,
as used herein, includes the container in which the component is
placed to be treated or anodized. Transport chamber, as used
herein, includes the container and pipes, etc. that store and move
an electrolyte or fluid to a reaction chamber.
[0031] Transportation channel 201 and reaction container 104 are
separated by an inner wall consisting of a lower portion 206, made
of an inert material, and an upper portion 207, part of which is
the counter electrode, and part of which is (unlike the prior art)
a non-conductive injection ring and includes a set of reaction
inlets or nozzles 210. Alternatively, the entire wall may be the
electrode. The reaction medium enters reaction container 104
through reaction inlets or nozzles 210 through portion 207. The
reaction medium enters reaction container 104 at a non-zero
horizontal angle and (unlike the prior art) at a non-zero vertical
angle relative to the surface of the component, part, aluminum
substrate, or working electrode 102. The horizontal angle to the
part is within the range of 15 to 90 (or -15 to -90) degrees,
preferably 60 to 70 (or -60 to -70) degrees. The vertical angle to
the component within the range of 15 to 85 degrees, preferably 20
to 40 degrees. Vertical angle, as used herein, includes the angle
relative to horizontal, and a vertical angle upward is greater than
zero, and a vertical angle downward is less than zero.
[0032] The reaction medium leaves reaction container 104 through a
reaction outlet 212 and returns to medium reservoir 202. The inner
wall (comprised of portions 206 and 207), and an outer wall 213 are
fixed to a bottom wall 214. Walls 206, 213 and 214 are comprised of
an inert material, such as polypropylene. Reaction container 104 is
closed by a moveable top lid made of an inert material such as
polypropylene, which includes a cover lid 219 and a mounting
fixture 220, and in which working electrode 102 is placed. Mounting
fixture 220 is exchangeable and specially designed for the
particular parts or working electrode 102 which is being anodized.
Fixture, as used herein, includes the reaction chamber and the
walls, inlets, cover, cathode, connections, etc. Cover (of a
reaction chamber or fixture), as used herein, includes the surface
over the reaction chamber of the chamber and can be partially open,
and/or have the component extending therethrough.
[0033] The upper portion of working electrode 102 is exposed to
air, enhancing the dispersion of heat accumulated in working
electrode 102 during processing. Selective formation of coatings on
working electrode 102 can be obtained in manner consistent with the
prior art, particularly U.S. Pat. No. 6,126,808, FIGS. 3 and 4,
such as using a top mask etc. The mounting and masking device
allows selective formation of coatings on the metallic substrate at
high speed as set forth in U.S. Pat. No. 6,126,808.
[0034] The reaction medium is sprayed toward the metallic substrate
through holes in the counter electrode in a manner that reaction
products (heat) are carried away from the metallic substrate
(working electrode). FIG. 3 shows a sectional view, at an angle
relative to horizontal, of an injection ring 301. A plurality of
inlets 1001 are shown, and are horizontally angled between 60 and
70 degrees. They are also at a non-zero vertical angle, as
discussed in more detail below.
[0035] As set forth in U.S. Pat. No. 6,126,808 the reaction medium
may be a solution of sulfuric acid and/or suitable organic acids.
The electrolyte is preferably stored and chilled to an appropriate
process temperature and pumped up into the reaction chamber at an
appropriate flow rate. The flow of direction of electrolyte is
toward the aluminum surface so heat is transported away from the
areas of heat production. The electrolyte is transported to the
reaction site in an outer circular inlet chamber and through the
counter electrode toward the component, such as an aluminum piston.
The counter electrode contains from one to 50, but preferably from
10 to 30 transport inlets to the reaction chamber. The counter
electrode is connected to the rectifier and acts as cathode
(negative). A pulse current pattern such as that set forth in U.S.
Pat. No. 6,126,808 is preferably used.
[0036] Referring again to FIG. 3, a sectional view of an injection
ring of portion 207 of the inner wall is shown. Injection ring 301
includes inlets 1001, and the section is at an angle equal to the
vertical angle of inlets 1001. If the sectional view was at a
horizontal angle, the inlets would appear to be ovals. Inlets 1001
are horizontally angled between 60 and 70 degrees, and thus direct
the fluid to the component at a non-zero horizontal angle. Directed
toward the component, as used herein, includes toward the component
either directly or obliquely, such that the shortest distance to
the component decreases.
[0037] Inlets 1001 are through an electrically non-conductive
material in the preferred embodiment. Examples of such electrically
non-conductive materials include ceramic, plastic, PVC, fiber
reinforced plastic, etc. The preferred embodiment provides that the
entire injection ring 301 is electrically non-conductive. Other
embodiments provide that portions between inlets 1001 are
electrically conductive. Electrically non-conductive, as used
herein, includes a material that can electrically insulate at the
voltages being used in the treatment.
[0038] A perspective view of portion 207 is shown in FIG. 4, and
includes injections ring 301 and a cathode (or counter electrode)
401. Cathode 401 is preferably comprised of titanium and is
vertically adjacent and directly below injection ring 301 (unlike
the prior art). Other embodiments provide for cathode 401 to be
directly above (still vertically adjacent) injection ring 301, or
adjacent and disposed between inlets 1001. Vertically adjacent, as
used herein, includes being contiguous with, in contact with, or
near, in the vertical direction.
[0039] Because the inlets are not through the cathode there is less
likelihood of the inlets being clogged by plating of dissolved
metals that enter the anodizing solution during processing of
alloyed materials. Rather, using this invention will limit unwanted
plating primarily in non-critical areas, such as on ring 401, or on
the surface of ring 301.
[0040] The inlets are at a non-zero vertical angle, and thus direct
the fluid toward the component at a non-zero vertical angle. FIG. 5
shows a vertical cross section of a component 102 in a fixture 220
in accordance with the preferred embodiment. An inlet 1001 is
shown, and is at a vertical angle of preferably between 20-40
degrees. Inlet 1001 appears to be an oval because the section is at
a zero horizontal angle, and inlet 1001 is at a non-zero horizontal
angle. Alternative embodiments provide for negative vertical
angles, and/or two or more non-zero vertical angles, and/or two or
more non-zero horizontal angles for inlets 1001. For example, every
alternating inlet could be at +30 and -30 degree vertical
angles.
[0041] Component 102 is a piston, and supported in position by a
spacer 501 on fixture 220. The reaction fluid enters through inlet
1001, as indicated by an arrow 503. Inlet 1001 is through
non-conductive ring 301. Non-conductive ring 301 is disposed
vertically adjacent cathode 401. Cover 219 is placed over fixture
220, and fluid passes between cover 504 and fixture 220. Unlike the
prior art, the underside of cover 505 is shaped to direct the fluid
to piston 102 by having an upward slope. More specifically, the
underside of cover 505 includes a first sloped region 507 and a
second sloped region 508. They combine to produce an non-zero
average slope. Alternatives provide for a single slope, a plurality
of slopes with abrupt changes joining the slopes or a continuously
changing slope. Shaped to direct the fluid, as used herein,
includes a profile that has a non-zero average slope, and can be a
single slope, a plurality of slopes, or a changing slope. Underside
of the cover, as used herein, is the surface of the cover closest
to the reaction fluid.
[0042] Fluid is directed by the underside of cover 505 and by
inlets 503 to piston 102, as shown by arrow 510. Fluid returns to a
storage chamber along a path shown by arrows 511 and 512. The shape
of the underside of cover 505 and the direction of inlets 503 help
create a laminar flow where arrows 510 and 511 are shown.
[0043] Thus, the invention provides for inlets or nozzles in the
fixture at non-zero vertical and horizontal angles, as well as
through material that is electrically non-conductive. The non-zero
angles, in cooperation with the sloped underside of the cover,
allows the electrolyte to roll into the ring groove on the piston
and refresh the electrolyte solution at the interface of the
anodizing area. This circulation of the electrolyte flow, shown by
arrows 510 and 511, allows the electrolyte to remove heat
effectively and refresh the fluid (electrolyte) at the surface of
the aluminum to create a dense oxide structure. Moreover, this
cooperation helps even out the electrolyte replenishing at the
anodizing interface reducing any potential hot spots in between the
electrolyte injection nozzles. Refresh the fluid at a surface, as
used herein, includes directing new fluid to the reaction surface.
Various alternatives include having non-zero vertical angles with
zero horizontal angles, with or without the sloped underside of the
cover and with or without the non-conductive inlet ring. Other
alternatives include having a non-conductive inlet ring with or
without non-zero vertical angles, non-zero horizontal angle and the
sloped (i.e., non-zero average slope) under side of the cover.
Additional alternatives include having an underside of the cover
that directs fluid to the component (such as a sloped underside),
with or without a non-conductive inlet ring, non-zero vertical
angles, and nonzero horizontal angles.
[0044] Numerous modifications may be made to the present invention
which still fall within the intended scope hereof. Thus, it should
be apparent that there has been provided in accordance with the
present invention a method and apparatus for a system and method
for electroplating that fully satisfies the objectives and
advantages set forth above. Although the invention has been
described in conjunction with specific embodiments thereof, it is
evident that many alternatives, modifications and variations will
be apparent to those skilled in the art. Accordingly, it is
intended to embrace all such alternatives, modifications and
variations that fall within the spirit and broad scope of the
appended claims.
* * * * *