Patent Application
20060243588
The present invention relates to a loading apparatus for electroplating processes and, more particularly, to an ergonomic loading apparatus for use in electroplating processes.
Generally, electroplating processes involve lowering a workpiece or part into a plating bath containing a plating solution. The workpiece or part may be mounted within a loading apparatus, which is configured to be lowered or inserted into the plating bath(s). The part is typically dipped several times in the same bath or several different plating baths. Each time the part is removed from one bath; the part is dipped in a rinsing bath, or a “tack tank” as commonly referred to by one of ordinary skill in the art, to remove excess plating material, prevent oxidation of the part and prepare the part for the next plating bath.
One example of a loading apparatus of the prior art for electroplating processes, and utilized by Pratt & Whitney in East Hartford, Conn., a division of the United Technologies Corporation, is depicted in
Loading apparatus 10 has a substantially rectangular container 12 having an inwardly sloping front wall 14, an inwardly sloping back wall 16, a pair of sidewalls 18, 19, a base 20. A bus bar attachment composed of a pair of plastisol stainless steel bus bars 22, 24 is mounted to base 20 underneath each respective receptacle area 30, 31 and between base 20 and another plastisol coated stainless steel bus bar 26. Bus bars 22, 24 are both threadingly secured to bus bar 26 and base 20 by four bolts 28. A round dowel 29, threadingly secured to bus bar 26 by a bolt 27, is designed to connect to a shaft (not shown) of a conveyor apparatus for use in a line for the intended electroplating process. Container 12 includes a pair of receptacles 30, 31, each designed to receive a turbine airfoil blade (not shown). Once the airfoil blades are pneumatically inserted within receptacles 30, 31, a cover 32 is threadingly secured to container 12 by fourteen threaded bolts 34 and two pairs of threaded bolts 42. Each threaded bolt 34 is fitted between a first o-ring 35 and cover 32 within a plurality of first threaded apertures 40 of cover 32, and proximate to both front wall 14 and backwall 16, and sealed with a second o-ring 37. Each threaded-bolt 42 is fitted between a plate 43 and cover 32 within a plurality of second threaded apertures 45 of cover 32, proximate to both first sidewall 18 and second sidewall 19. Each receptacle 30, 31 includes four sidewalls 44, 46, 48 and 50 and a base 52 having an aperture 54. Sidewalls 44, 46 are formed in part by a center portion 33 of cover 32 and a center portion 39 of base 20.
As known to one of ordinary skill in the art, each airfoil blade contains a hollow cavity. In order to prevent plating solutions of one bath from entering the interior cavity of a blade and then contaminating another subsequent bath, the hollow cavities are typically filled with wax. As a result, an operator of the electroplating process must manually fill each airfoil blade's interior cavity. Each turbine airfoil blade is then inserted platform end first into each receptacle 30, 31 using a pneumatic ram or other similar device capable of generating 110 pounds per square inch (psi) to force each airfoil blade into each receptacle 30, 31. Each receptacle 30, 31 requires an airfoil blade in order to prevent transporting electroplating solutions from one bath to another and thus contaminate the baths.
Each airfoil blade must touch the interior base portion within each receptacle 30, 31 in order to receive electrical current from bus bars 22, 24 and 26. When the airfoil blade did not connect in part or completely with the receptacle's interior base portion, the plating would not evenly and/or completely adhere to the blade tip. The resulting unevenly plated airfoil blade would require a quality inspection to determine whether the blade would be scrapped or could be salvaged. In order to salvage an unevenly coated blade tip, the entire cover of the blade must be stripped, the surface cleaned and the airfoil blade reinstalled into loading apparatus 10. This process involves numerous steps which could prevent that particular airfoil blade from being re-plated for over a day or longer. Moreover, if another airfoil blade was not readily available for insertion into the empty receptacle, loading apparatus 10 would be taken off-line in order to prevent the potential contamination of the electroplating baths.
Once the operator has loaded the airfoil blades into receptacles 30, 31, the operator manually aligns cover 32 with the airfoil blades and secures it to container 12. Cover 32 weighs over approximately thirty pounds (30 lbs.) so the operator must be physically capable of lifting, placing and securing cover 32 onto container 12. Once cover 32 is in place, the operator manually inserts and tightens each bolt 34, 42 using a rachet, torque wrench, or other similar tool. Since an air tight seal must be achieved, it was not uncommon for the operator to apply the tool too strongly and accidentally strip a bolt.
At this time, the operator would attach loading apparatus 10 to a mechanized conveyor apparatus (not shown). Upon completion of the process, loading container 12 is detached from the conveyor apparatus and cover 32 is removed. As described earlier, one or more bolts 34, 42 were typically stripped while installing cover 32. In order to remove stripped bolts 34, 42, a maintenance person equipped with a cutting wheel, saw or similar device would cut away each stripped bolt thus requiring additional time and manpower and increasing the cost of plating the airfoil blades. Once bolts 34, 42 were removed, cover 32 was again manually removed by the operator and each blade tip was visually inspected to determine whether or not an acceptable plating was achieved.
The process for coating airfoil blade tips proved to be time consuming, inefficient and cost prohibitive. The tooling costs and additional manpower contributed both time and costs to each run of the production line. The contamination of plating baths also contributed additional time and even temporarily shut down the process to replace a bath and/or tack tank solution. If the operator discovered loading apparatus 10 was carrying excess bath or tack tank solution, then the operator was required to dismantle loading apparatus 10 in order to clean and remove the contaminants. Likewise, if the operator discovered an airfoil became contaminated, then the airfoil blade had to be removed and replaced, if possible, in order to prevent future contamination. Again, the production line would be halted to remove the airfoil blade, and either replace the blade or halt the line if a replacement blade was not available.
In addition to line problems, operators required a pneumatic ram or other device to insert each airfoil blade into receptacles 30, 31. Operators also had to be physically capable of manually lifting, aligning and placing a 30+ lbs. cover 32 onto container 12, and then securing cover 32 to container 12 using a torque wrench, rachet and the like, to tighten eighteen bolts. Inevitably, one or more bolts would be stripped and require a technician or maintenance personnel to cut or saw off the stripped bolt from loading apparatus 10 in order to remove cover 32. Moreover, and even if the production line operated smoothly, there was always a question as to whether all of the airfoil blade tips would be coated properly.
Consequently, there exists a need for an improved loading apparatus designed to receive airfoil blades without the use of a pneumatic tool and capable of maintaining the integrity of its seal to prevent contamination of the airfoils as well as baths and tack tanks.
In accordance with the present invention, a loading apparatus for use in electroplating processes broadly comprises a container comprising a front wall, a back wall, a first sidewall, a second sidewall and a base having an interior area comprising a first receptacle and a second receptacle separated by a dividing wall; an h-beam comprising a first lip and a second lip is disposed contiguous to and transverses the first sidewall and the second sidewall, and disposed upon the dividing wall; a first cover defined by a first perimeter and comprising a plurality of second apertures designed to sealingly receive an airfoil blade fitted with a gasket, and a plurality of first clamping mechanisms along the first perimeter disposed upon and aligned with the first receptacle; a second cover defined by a second perimeter and comprising a plurality of second apertures designed to sealingly receive an airfoil blade fitted with a gasket, and a plurality of second clamping mechanisms along the second perimeter disposed upon and aligned with the second receptacle; a plurality of first electrical contact assemblies disposed within a first base of the first receptacle; a plurality of second electrical contact assemblies disposed within and a second base of the second receptacle; a bus bar mounted underneath the base of the container and in contact with the plurality of electrical contact assemblies; and a round dowel comprising an attachment to an apparatus for an electroplating process secured to the bus bar opposite the base of the container.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
Like reference numbers and designations in the various drawings indicate like elements.
The loading apparatus of the present invention is designed to overcome the disadvantages of the prior art and accomplish the following objectives: (1) eliminate the need to fill the hollow cavity each airfoil blade with wax or other sealing material; (2) eliminate a press for loading airfoil blades into the apparatus; (3) eliminate the cover previously utilized in the loading apparatus of the prior art; (4) eliminating the need to cut stripped bolts; (5) eliminate the need for an additional operator/technician/maintenance personnel; (6) enable complete connection of each airfoil blade with its electrical contact; (7) enable each airfoil blade to remain dry throughout the production line; (8) enable the loading of airfoil blades for each run in half the time previously required; (9) reduce by approximately eighty percent (80%) the need to rework airfoil blades; and (10) reduce the amount of drag or transfer of contaminants from one tank to another during the production line.
Referring now to
Loading container 112 also includes a first cover 134 having a substantially rectangular shape defined by a first perimeter 144 and comprising a plurality of first apertures 136 and a second cover 138 also having a substantially rectangular shape defined by a second perimeter 147 and comprising a plurality of second apertures 140. Each cover 134, 138 is designed to sealingly receive an airfoil blade 139 fitted with a gasket 141 (See
Each cover 134, 138 further includes a latching means or a first and plurality of second clamping mechanisms, respectively, mounted to each cover 134, 138 along a perimeter 144 of loading container 112 and proximate to the sloping front wall 114 and sloping back wall 116. The clamping mechanism may comprise a toggle clamp 142 mounted to each cover 134, 138 using a plurality of bolts, screws, similar fasteners and the like. For purposes of illustration and not to be taken in a limiting sense, each toggle clamp 42 is fastened to its respective cover 134, 138 using four screws 145. Each clamp 142 of first cover 134 includes a latch 143 and a corresponding first latch hook 148 mounted to a first hinge piece 146 threadingly attached to a first support ledge 176 integral to loading container 112 and a first reinforcement piece 180. First hinge piece 146, first support ledge 176 and first reinforcement piece 180 all share a threaded aperture 150 which receives a threaded bolt 152 that threadingly secures all three pieces together. Likewise, each clamp 142 of second cover 138 includes a latch 143 and a corresponding second latch hook 162 mounted to a second hinge piece 160 threadingly attached to a second support ledge 178 integral to loading container 112 and a second reinforcement piece 188. Second hinge piece 160, second support ledge 178 and second reinforcement piece 188 all share a threaded aperture 150 which receives a threaded bolt 152 that threadingly secures all three pieces together.
Each receptacle 122, 124 is defined by four sidewalls and a base; however, only two pairs of sidewalls and the respective base of each receptacle 122, 124 is depicted in
Each electrical contact assembly comprises an assembly body 216 having a spring-like electrical contact 212 secured by a bolt 217 disposed within an aperture 219. Assembly body 216 may be disposed within an aperture extending through base 112 and a plate 225 disposed between base 112 and a bus bar 230, and sealingly disposed within a well 224, 226 of bus bar 230. Bus bar 230 may be mounted underneath base 120 of loading container 112. An o-ring 221, 223 may be concentrically disposed about assembly body 216 and between plate 225 and a sleeve 220, 222 also concentrically disposed about assembly body 216. For purposes of illustration and not to be taken in a limiting sense, only a first electrical contact assembly disposed within said first receptacle and a second electrical contact assembly disposed within said second receptacle are shown. A round dowel 232 is threadingly secured to bus bar 230 by a bolt 228, which is designed to connect to a shaft (not shown) of a conveyor apparatus for use in a line for the intended electroplating process.
Electrical contacts 212 comprise a spring-like design such that its surface is elevated high enough to first make a connection with an airfoil blade inserted approximately seventy-five percent (75%) before being inserted completely within either receptacle 122, 124. As long as an operator can manually insert the airfoil blade and its gasket within apertures 136, 140, the airfoil blade is ensured to adequately connect with electrical contact 212.
Loading apparatus 100 of the present invention possesses numerous advantages over loading apparatus 10 of the prior art illustrated in
Many disadvantages of the prior design involved loading airfoil blades into loading apparatus 10. For instance, in order to prevent plating solutions from one bath entering the interior cavity of a blade and then contaminating another subsequent bath, the operator filled the hollow cavities of each airfoil blade with wax. Unfortunately, if a seal did not form between cover 32 and loading container 12, plating solution and tack tank solution would still enter receptacles 30, 31 and the interior cavities of the blades too. Now, a gasket is fitted about each airfoil blade proximate to the root section prior to insertion into receptacles 122, 124. The gasket creates a seal within each aperture 136, 140 of covers 134, 138 thus ensuring both plating and tack solutions do not enter receptacles 122, 124 or the interior cavities of the airfoil blades. Moreover, the ease with which an airfoil blade may be inserted ensures the operator will not require assistance from anyone else. It is estimated that fifty percent (50%) less time is required to load a complete set of airfoil blades into loading apparatus 100 as compared to the amount of time required to load a complete set of airfoil blades into loading apparatus 10.
Another disadvantage involved the operator's reliance upon utilized a pneumatic ram or other device capable of generating enough pressure to force each airfoil blade into place. However, this technique still did not ensure the airfoil blade made an adequate connection with the interior surface of the base of its receptacle. The present design now permits the operator to simply fit a gasket about an airfoil blade and manually insert the blade into the receptacle. The operator can now visually determine whether the airfoil blade connects with electrical contact 212, 214 as the spring design ensures the airfoil blade makes contact after being inserted approximately 75% of the intended distance. As described beforehand, if the airfoil blade did not connect in part or completely with the receptacle's interior base portion, the plating solution would not evenly or completely adhere to the blade tip. The resulting unevenly plated airfoil blade would then require a quality inspection to determine whether the blade would be scrapped or salvaged. Now, the spring design of the electrical contact along with the manual insertion of each airfoil blade ensures the connection is made and maintained. As a result, the need to rework parts, that is, salvage, strip and plate the airfoil blade tip again, has been reduced approximately 80% compared to employing loading apparatus 10 of the prior art.
It is to be understood that the invention is not limited to the illustrations described and shown herein, which are deemed to be merely illustrative of the best modes of carrying out the invention, and which are susceptible to modification of form, size, arrangement of parts, and details of operation. The invention rather is intended to encompass all such modifications which are within its spirit and scope as defined by the claims.
