Abstract:
At least one roller connected to a clip via an axle. The clip capable of being removably attached to a wicket, the wicket being well known in the art. The roller provides anti-friction engagement of wicket workpieces that are handled by wickets in industrial processing such as the processing of tinplate sheets.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     BACKGROUND 
     There exist many ways to process metals for commercial use. One example of a processed metal is Tinplate, or terneplate. Terneplate is used for many products such as soup cans, coffee containers, cookie tins, or soda cans to name a few examples. The tinplate is formed into sheets and these sheets are processed by sheet handling machines. The machines for handling terneplate are large and used for, among other things, coating the terneplate with decorative graphics often seen on soup cans or coffee tins. Throughout this processing the sheets are manipulated, or manhandled, and subjected to varying degrees of force, thrusts, twists, turns, torques and the like. Wickets are used in these machines to facilitate handling the sheets. 
     A wicket is grated and looks like a gate. They are used in the tin sheet coating industry and are often located within wicket ovens. Wickets are used to support sheets of material, usually tin sheets, as they are being processed to make product, the process of drying a painted tin sheet for instance. Aside from being used for supporting metal sheets, wickets are also used to manipulate metals, for example by supporting the tin sheet in a substantially vertical position along a moving conveyor. One other way the sheets are manipulated is by being slid onto and off of the wickets during processing, and for placing dried coated sheets onto a cutting machine, for instance. Wickets are well known and used in many industries, one such industry is a sheet printing operation as depicted in  FIG. 5 . Because wickets are generally made from a heavy metal, a wicket often scratches the tin during processing. 
     As is evident from the foregoing, several problems can occur when metals, such as tin sheets, are manhandled with processing machines, particularly those machines using wickets or the like. Tin, or the like, is a soft metal and prone to being scratched. Decorative graphics or other coatings applied to the metal can be ruined by rubbing, smudging or scratching for example. This problem renders the metal unusable for commercial purposes and the metal must then be reprocessed or thrown away. 
     In the United States alone millions of metal sheets are scratched from contact with wickets. Entire skids of tinplate are scrapped or must be hand sorted to remove the damaged sheets. A skid of tinplate has 1500-1800 sheets when delivered. Some end users will scrap the entire pallet of tin plate and send them back to the coating supplier if they even find a single scratched sheet, this can cost millions of dollars. To date, there is no easily installable solution to help this situation. 
     Information relevant to attempts to address these problems can be found in U.S. Pat. No. 2,406,000 (Dawn). However, this reference suffers from one or more of the following disadvantages: 1) difficult to install, 2) expensive to implement, 3) ineffective in protecting the metal from scratching during processing. Nothing mentioned in this Background section is admitted to be prior art with respect to the present invention. 
     For the foregoing reasons, there is a need in the industry for an apparatus that is easy and inexpensive to install and minimizes the friction between wickets and metal thereby preventing damage to the metal from the handling done by wickets. 
     SUMMARY 
     The present invention is directed to an apparatus, the utility of which is to prevent damage, scratching to name one example, of metals during processing, such as the processing of tin sheets by wickets. The inventive device is small and inexpensively made. When attached, either singularly or in a plurality, to a wicket, the device provides an anti-friction surface for metal sheets to lie upon as they are manipulated during machine processing, such as by sliding onto and off of a wicket, to name one example of manipulation. Such a device is valuable to industry users because it can eliminate the waste from wicket damaged tin sheets, is easy to install on existing wickets, and is inexpensive to implement. 
     One embodiment of the invention, which the inventor has reduced to a working example, comprises at least one roller that has a passage or hole. An axle is located within the passage and when engaged with the roller easily allows the roller to spin about the axis of the passage. The axle is prevented from slipping through the passage via a retainer part on either side of the roller, for instance. There is a clip having at least two ends, a clip end and a support end. At least one axle end is attached to the support end of the clip, the support end being removably attached to a wicket. As described briefly above, the wicket is part of a metal processing line such as those found in a wicket oven used in a metal sheet coating operation for example. It is further useful that the invention can be configured to provide for easily maintaining or replacing the roller via the axle being removably attached to the support end. 
     Another embodiment of the invention comprises at least one low friction surface engaging with at least one holder and a clip having a clip end and a support end. The embodiment further includes the least one holder being attached to the support end and the clip end being removably attached to a wicket. Additionally, the at least one holder could be removably attached to the support end allowing for easy replacement or maintenance of the roller and holder. 
     A method embodiment of the invention for protecting sheet stock from damage during processing, comprises connecting one or more low-friction devices to a wicket assembly, each low friction device including at least one roller with a central passage therethrough, an axle extending through the central passage, the axle being retained within the central passage by retainers connected to the axle with the roller captured between the retainers. There is a clip connected to an axle end and attaching the one or more low-friction devices to the wicket assembly with the clips of the one or more low-friction devices clipped to the wicket assembly and the rollers of the one or more low-friction devices extending in the same direction from the wicket assembly; and supporting, during processing, a sheet of material via the rollers of the one or more low-friction devices contacting the sheet and spacing apart the sheet and the wicket assembly. 
     The nature of the roller or low friction surface is such that it provides an anti-friction surface between the tin sheets and the wickets that work on the sheets. The nature of the roller is most easily understood to be wheel-like or substantially shaped like a ball whereas the low friction surface could be a smooth surface such as glass or steel. The inventor further envisions that a roller or low friction surace of various configurations, shapes, sizes, coatings, or material compositions is possible, however, each such roller or low friction surface would serve the purpose of providing an anti-friction surface in a manner similar to that described above. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       These and other features, aspects and advantages of the present invention, which has actually been reduced to practice by the inventor in one embodiment, will become better understood with regard to the following description, appended claims, and accompanying drawings where: 
         FIG. 1  shows a perspective view of an apparatus embodying features of an of the invention. 
         FIG. 2  shows a perspective view of the apparatus in  FIG. 1  embodying features of an example of the invention and showing the apparatus being attached to a wicket rod. 
         FIG. 3  shows a perspective view of another version of an apparatus embodying features of an example of the invention attached to a wicket assembly and supporting a sheet of tinplate. 
         FIG. 4  shows a perspective view of another version of an apparatus embodying features of an example of the invention. 
         FIG. 5  depicts a sheet printing operation which is well known in the art. 
         FIG. 5A  is a section view taken from FIG. 5  showing an embodiment of the invention acting on a workpiece. 
     
    
    
     DESCRIPTION 
     Overview. 
     As shown in  FIG. 1 , an apparatus embodying features of an example of the invention comprises a roller  1 , having a passage  2  running through its center. Within the passage  2  is located an axle  3  being prevented from passing through the passage  2  via a retainer clip  6  on either side of the roller  1 . The apparatus further includes a clip  7  having a support end  4  and opposing clip ends, such as the clip end  5 . The axle  3  is connected to the support end  4 . 
     As shown in  FIG. 2 , a perspective view of the apparatus in  FIG. 1 , embodying features of an example of the invention and showing the apparatus being attached to a wicket rod, comprises a roller  1  having a passage  2  running through its center. Within the passage  2  is located an axle  3  with at least one axle end  9  being prevented from passing through the passage  2  via a retainer clip  6  on either side of the roller  1 . The apparatus further includes a clip  7  having a support end  4  and opposing clip ends  5 , with the axle  3  being connected to the support end  4  and the clip  7  being attached via its clip ends  5  to a rod of a wicket  8  of a type which is well known in the industry. 
     As shown in  FIG. 3 , a perspective view of an apparatus embodying features of another example of the invention attached to a wicket assembly and supporting a sheet of tinplate comprises the apparatus  10  attached to a wicket assembly  11  and supporting a sheet of tinplate  12  which contacts a roller  13 . 
     As shown in  FIG. 4 , a perspective view of another version of an apparatus embodying features of an example of the invention comprises a low friction surface  10  being attached to holder  15  and a clip  14  having a clip end  19  and a support end  16 . The apparatus further includes a holder  15  attached to the support end  16 . When the clip end  19  is attached to a wicket assembly  17  the low friction surface  10  contacts a sheet of tinplate workpiece  18 . 
     As shown in FIG. 5 A, a section view taken from  FIG. 5  showing an embodiment of the invention acting on a workpiece comprises a sheet of tinplate workpiece  12  in an alternative position having moved off a first at least one roller  13  attached to a first wicket  11 . The workpiece having passed through alternative positions  12   a  and  12   b  and coming to rest on a second at least one roller  13   a  attached to a second wicket  11   a.    
     The previously described versions of the present invention have many advantages, including that, by having the sheet in contact with a roller of the apparatus, the sheet is prevented from contacting the wicket assembly and scratching from the wicket assembly is effectively eliminated. Additionally, because the apparatus is small and merely clips onto the wicket assembly, it is inexpensive to manufacture and implement. The particular shapes and configurations of the apparatus as set forth above are preferred because of the abovementioned advantages, but are not required in all versions of the invention. 
     Although the present invention has been described in considerable detail with the reference to certain preferred versions thereof, other versions are possible. For example, the roller of the apparatus might be a surface that is low friction by its nature, such as glass, and provide the friction reduction properties of the apparatus without the use of a rotating roller such as the embodiment depicted in  FIG. 4 . Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein. 
     Insofar as the description above and the accompanying drawings disclose any additional subject matter that is not within the scope of the claims below, the inventions are not dedicated to the public and the right to file one or more applications to claim such additional inventions is reserved. 
     The reader&#39;s attention is directed to all papers and documents which are filed concurrently with this specification and which are open to public inspection with this specification. The contents of all such papers and documents are incorporated herein by reference. 
     All the features disclosed in this specification (including any accompanying claims, abstract, and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalents or similar features.