US3033776A - Anodizing rack - Google Patents

Description

y 1962 E. B. ROSNER 3,033,776

ANODIZING RACK Filed Sept. 21, 1959 INVENTOR: ERNEST B, ROSNER Y B 0 MVQ ATT'YS United States Patent 3,033,776 ANODIZING RACK Ernest B. Rosner, 355 Russet, Highland Park, Ill. Filed Sept. 21, 1959, Ser. No. 841,123 6 Claims. (Cl. 204-297) This invention relates generally to plating and the like processes and more particularly, concerns a novel adjustable rack structure for use in the process of anodization of articles of varying types and dimensions.

The process of anodization is somewhat different from the general art of electroplating as it is commonly practiced. In ordinary plating of metals, a metal is deposited from a chemical bath, generally of its own salt; the article to be plated usually comprising one of the electrodes, generally the cathode, and a bar or the like of the plating metal acting as the anode. The anode is arranged to be immersed in the chemical bath and is subject to the chemical action thereof. Metal is removed from the anode and is plated upon the surface of the cathode by means of well-known electrolytic action. Thus, the anode is gradually reduced in weight by the loss of the metal therefrom. The thickness of the coat and rapidity of the process is determined by the amount of current being passed and the particular nature of the chemical bath.

In anodization, the process primarily consists of oxidizing the surface of an article by passing a current through the acid bath in which said article is immersed. The oxide layers formed on the surface are generally porous and capable of being penetrated by other chemicals such as various colored dyes and the like from solutions with which the article is subsequently treated. After a certain thickness of oxide coating is formed upon the article, it is removed from the bath, dipped into the dye solution and then, the coating is sealed as, for example, by treating with hot water or other chemical sealers. The dye is not merely absorbed upon the surface of the article, but is ingrained in the actual oxide coating, said coating actually intermolecularly uniting with the article. The oxide coating may be sealed without prior treatment with the dye or other coloring agents to form a protective, weather impervious, rustproof and exceptionally strong and thin coating.

The process of anodization has been used successfully to provide protective and decorative coatings for metals generally limited to aluminum, titanium, Zirconium, tantalum and metals of that family. The articles to be thus treated comprise the anode of the cell, the oxidation taking place because of released nascent oxygen at the said anode. The articles themselves may be directly used as the anode, however, since the entire surface of the articles is generally desired to be treated, and only that surface which is immersed in the bath will be anodized, there must be holders for suspending the articles in the bath. These holders or'racks must be strong enough to hold the articles, must have secure holding means thereon to insure good electrical contact between it and the articles, and also must conduct suflicient current therethrough so that the entire assemblage, rack and articles may function properly as the anode of the cell.

The use of dissimilar metals in the bath is to be avoided, and hence any structure used to support the articles suspended in the bath must not only be capable of supporting said articles and carrying the current required but must, in addition, he made of a metal compatible with the solution and current used.

It has in the past been difficult to provide anodizing racks of aluminum which provide the desired electrical contact and securely hold the articles due to the basic softness of this metal. In contrast, titanium metal racks are strong and provide sufiicient capacity to assure adequate current density to anodize substantial numbers of individual parts held thereby. Because of its high corrosion resistance and the highly corrosive environment of its operation, the use of titanium is highly desirable, if not imperative in certain circumstances. Titanium racks are little affected by the chemical baths into which they must be immersed and since they are so resistant to deterioration, consistent tensions and electrical contact may be maintained throughout the anodization runs. Moreover, aluminum metal is coated with a layer of the anodic oxide with the result that its current carrying capacity is markedly reduced and therefore racks made of aluminum must be stripped of their oxide coating by stripping solutions and treatment, said treatment occurrring often during the life of the rack and being extremely detrimental to said rack necessitating its frequent replacement. Titanium has no such current resisting properly and thus does not need repetitive stripping treatments. However, although titanium is most preferred, prior racks utilized entirely too much metal to make the use of titanium economically feasible.

The primary object of this invention is to provide a structure for anodizing racks whereby the racks will hold the articles very securely, provide the necessary electrical contact, conduct the current involved and said structure will economically permit the manufacture thereof from such advantageous but expensive metals as titanium.

Another object of the invention is to provide an anodizing rack which is adjustable so as to accommodate substantially different parts or articles while maintaining proper securement and spatial distribution of said articles during the anodization process. A substantial limitation of prior racks rests in their difliculty of revision, said racks being commonly designed for a particular size and shape part. Because relatively short runs of parts may be consistently called for, and each part has a rack constructed particularly for its size and shape, requiring therefore, frequent changes of said racks to be made. Many of said racks are discarded due to a change in the size or shape of the particular part, thereby resulting in a high rate of production time-loss due to the required replacement of said racks and substantial time wastage in having idle racks. In contrast adjustable racks may be quickly shifted from job to job, while fixed position racks were forced to wait for a particular job before utilization. Large overhead costs due to the substantial storage space required for a complete inventory of racks as well as increased purchase costs normally associated with style or model changes of parts are substantially lessened by the construction of the invention.

Still another object of the invention is to provide in an adjustable anodization rack novel means for instantaneously clamping the holding discs thereof at any desired location along the elongate member constituting the spline bar of said rack, said means being characterized by its relatively simple welded construction and its adaptation to rapid adjustment.

Another object of the invention is the provision in a single anodizing rack of disc members of a construction permitting the secure grasping of articles requiring substantially different types of holding means.

Since the racks are eventually consumed, the invention teaches how to produce a rack which is extremely economical to manufacture, being simple and Without complexity in structure. Economy in the amount of a metal used is extremely important in permitting the use oftitanium and like expensive metals. herein not only permits such matcrials use but provides a structure wherein the minimum amount of material will support a Wide variety and weight of articles. The object of the invention contemplates the provision of justsuch a compact and efficient structure.

An additional object of the invention lies in the pr0vi- Patented May 8, 1962.

The economical structure a, a) sion of a structure of the character described wherein said rack will be free from fluid traps characteristic of many racks heretofore used. Because of the substantial amount of current required, the weight and members of parts re-- quired to be carried, and general usage of aluminum rack members heretofore utilized said rackscomprised elongate rod or bar members having the holding means attached in innumerable ways but were of necessity of solid construction. The points at which the holding means were connected to said rod or bar were a constant source of fluid traps capable of staining parts, contaminating solutions, and causing erosion of said bars and connections necessitating costly repair and replacement of the racks. Moreover, such rod or bar members constitute an impedance to proper circulation of the chemical solution during the anodizing process. A further object of the invention is to provide a rack structure which does not interfere with the circulation of said chemical solution and thereby also increases the available surface for anodizetion and improves upon the control of said process. Thus a more uniform coating thickness is provided which is essential to specification compliance and/ or color match.

With the foregoing and other objects in view as will appear as the description proceeds, the invention consists of certain features of construction, arrangement and a combination of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in the form, proportion, size and minor details of the structure maybe made without departing from the spirit or sacrificing any of the advantages of the invention. 7

Referring now to the drawings: FIG. 1 is a perspective view of a rack combination constructed in accordance with the invention. and having three pair of discs thereon suitable for use in supporting difierent kinds of articles.

FIG. 2 is a fragmentary enlarged view of a portion of the elongate spline member of said novel structure.

FIG. 3 is an enlarged fragmentary view of a portion.

the articlm secured thereto acting as the anode for said cell. The hook member 12 which is shown in broken outline is just one of many diflerent means available to suspend said rack into the chemical bath. The entire rack is preferably formed'of titanium metal, but such other 4 relatively thin top and bottom plates 16, 17 and a pair of parallel side walls 18, 19 of substantially greater thickness than the said plates.

The rack 10 of FIG. 1 is made up of three pairs of disc members all mounted on the spine bar 14 of said rack. The discs of FIG. 1 are designated as pairs, 22A and 2213, 24A and 24B, and 26A and 268, the upper disc of each pair being characterized by letter A and the lower member by the character B. All of the discs have substantially the same configuration with the exception of the tips of the fingers and possibly the manner in which the grain of the metal is arranged.

Each disc is preferably stamped from a circular blank of titanium or any other metal h'om which the spline member 14 is made. Saiddisc is provided with a central circular portion 31 which is imperforate except for the aperture 32 at the center, said aperture 32 being of a configuration to easily permit'the discs to slide along the bar metals as aluminum, tantalum, zirconium and others of this family and their alloys may be also advantageously used. Thehook member 12 may be made of other than the material comprising the rack member 10, however, if so, said material must be conductive and must not be immersed in the chemical anodizing bath.

The rack 10 comprises a vertically disposed, hollow member 14 of substantially polygonal cross-section, the particular configuration of the illustration being rectangular. A particular feature of the invention lies in the novel construction for the spine bar itself which is best illustrated in FIG. 2. The spine bar 14 comprises a pair of elongate,

scribed as an elongate, hollow, rectangular tube having 14. Thus, the apertures 32 in the discs as illustrated are rectangular as shown in FIG. 3. Each disc has a plurality of radially extending fingers 33 which are formed by removing elongate, narrow triangular portions of the metal in any suitable process. to be horizontal and disposed normal to the long dimension of the bar '14. The fingers 33 of each disc are bent angularly to the circular portion along the circle at 34 defining a firusto-conical surface thereby.

The circular portions 31 are thus defined by the connected ends of the fingers 33. The bending of the fingers at this point assists in rendering the fingers 33 resilient, thereby enabling the articles to 'be grasped more effectively.

Secured to the surface 31 of each disc member bridging the passageway :32 adjustable clamping means 40 is provided which comprises a pair of L-shaped lug members 41,42 having one surface thereof fixedly secured to the surface 31 of said disc adjacent the long edge of passageway 32. In a perpendicular plane to that of the disc member, lugs 41, 42 have upstanding integral flange members 44, 45 forming said L-shape. The upstanding portions 44, 45 are parallel and juxtaposed one to the othcr, but are spaced apart by bridging members 46, 47. Welded to the surface of each upstanding flange member away from the edge of the passageway 32 are rectangular, relatively thick bar members 5-1, 52, the ends of which are provided with threaded passageways 53 so as to accommodate bridging bolts 46, 47. The leg members 44, 45 of the upstanding lugs41, 42 are somewhat resilient so that when said bolts are tightened, said inner surfaces of portions 44, 45 of each lug member engage the plate surfaces 16, 17 of the spine member 14. This serves as means whereby the said discs are secured in position along the length of said spine member.

The essence of the invention lies in the economy of usage of material thereby permitting the use of expensive materials such as titanium, tantalum and zirconium. Not only does the spine structure shown herein economize on material but the additional advantage is gained because the entire spine immersed in the chemical bath is hollow, whereby freer circulation is possible within the chemical bath, thus avoiding the presence of possible corrosion causing fluid traps common when solid spine members are used. t 7

Referring now in greater detail to the discs, it will be seen that various types of tips may be provided on the ends of the fingers 33. These are for different purposes and uses. For example, in the discs 22A and 228, the tips are notched as at 55 and are rectilinear along their respective ends with a slight bend 56 adjacent their free ends.

In discs 24A and 24B arcuate notches 57 are provided and the bends 58 are not as great. The discs 26A and 26B are not notched, but instead provided with shallow depressions 59 which are preferably perforated, the depressions being formed on the dished side of the discs.

It will be seen that each of the discs is of generally The circular portion 31 is adapted dish-like configuration, the depth and total diameter being a matter of choice with the user. The discs are used in pairs, and since the fingers of each pair will be aligned, the fingers of each pair will cooperate to hold articles, either in compression or in tension. Like pairs may be used if the articles to be carried by the rack are similar, yet different pairs of discs may be also set in place along the spine member. Different kinds of tips assist in supporting different types of articles as illustrated in FIG. 1.

Thus a great many parts may be mounted in a simple manner by means of the pairs of discs described. Also because of the ease of adjustability of the clamp means 40, the discs may be spaced at varying points along the length of the spine member so as to accommodate varying lengths of articles on the same rack, yet remaining securely clamped in position to hold the articles tightly through the anodizing process. While prior devices are dependent on stop members or additional support members thus limiting the range of size and space allotment on the spine, the continuous plate surface of the spine cooperating with the clamping means welded to the discs allow substantially any desired spacing of said discs along the length of said spine.

The assembly of the discs upon the spine bar is a relatively simple procedure. The disc members are simply slidably engaged upon the spine member 14 by slip ing the bottom end thereof through the passageway 32. "l hey are then arranged in a desired matched relationship and the bolts 46, 47 of the clamping means 40 are tightened, securing the said disc upon the spine 14. The book member 12 shown in broken lines, is adapted to slip between the two plates 16, '17 at the top of the spine and is secured therebetween by any known means such as keying, riveting, and the like. The said hook 12 may also be removably secured therebetween. Plate 61 may be welded on each plate surface so as to give additional support to any means used to secure the hook member 1 2. to the member 14; Note that no wedges are necessary, no special spacers, no washers, etc. Since all parts of the assemblage are preferred not to be manufactured from dissimilar metals, the elimination of additional parts results in a sub stantial cost saving to the user of an expensive material such as titanium, the like above mentioned metals and/ or their alloys.

Also because of the ease of dismantling, storage space formerly required with prior devices can be released for more profitable purposes.

While the invention is principally directed to a structure useful in the anodizing process, the same is not limited thereto, but is equally applicable to various electroplating and electropolishing processes wherein a large number of articles are required to be suspended in electrochemical baths and have electric current passing through the same. Other processes which require the support or suspension of members in baths and solutions irrespective of whether or not current passes through the members may advantageously use the invention with superior results and with great economy.

It is believed that this invention, its mode of construction and assembly, and many of its advantageous advantages should be readily understood from the foregoing without further description, and it should be also manifest that, while a preferred embodiment of the invention has been shown and described for illustrative purposes, the specific details are nevertheless capable of wide variation within the purview of this invention as defined in the appended claims.

What it is desired to secure by Letters Patent of the United States is:

1. A rack for supporting articles in a bath comprising, at least one pair of dish-like metal members each having a plurality of radially extending fingers thereabout, an elongate metal spine bar, each dish-like member having a passageway in the central portion thereof having substantially similar configuration at the cross-section of said spine bar thereby allowing passage of said spine bar therethrough, each of said dish-like members being removably secured to said spine bar with the fingers of one metal member aligned with the fingers of the other and with the tips of the fingers of one member spaced from the tips of the fingers of the other, adjustable clamping means fixedly secured to each of said dish-like members whereby said dish-like members are adapted to be adjustably secured along the length of the spine member, said spine member comprising, an all-welded hollow rectangular assembly having a pair of electrically conductive relatively thin sheet metal plate members juxtaposed and spaced one from the other and a pair of relatively thick elongate bar members interposed between said plate members at opposite elongate edges of the plate members and secured thereto by welding, said pair of plate members extending lengthwise a short distance from said bar members at one end thereof to provide a passageway adapted to receive a connector member disposed between the plate members at said end of said spine bar, and reinforcing means for said plate extensions comprising, overlapping plate members secured to each plate member at a point slightly below the end of said bar members and extending partially over the length of said extensions.

2. A rack for supporting articles in a bath comprising, at least one pair of dish-like metal members each having a plurality of radially extending fingers thereabout, an elongate metal spine bar, each of said dish-like members having a passageway in the central portion thereof, having substantially similar configuration as the cross-section of said spine bar thereby allowing passage of said spine bar therethrough, said dish-like members being removably secured to said spine bar with the fingers of one metal member aligned with the fingers of the other and with the tips of the fingers of one member spaced from the tips of the fingers of the other, adjustable clamping means fixedly secured to said members whereby said dish-like members are adapted to be adjustably secured along the length of the spine member, said clamping means comprising, a pair of L-shaped lug members each having a flat base and an upstanding slightly resilient vertical member integral therewith, said lug members disposed on each side of and adjacent the elongate edges of said passageway in each of said dish-like members with said bases secured to the dish-like members and said upstanding members juxtaposed and in parallel planes one to the other, a pair of fiat parallel bar members disposed in juxtaposed relation one on each inner surface of said upstanding members, the surface planes thereof being parallel to the vertical planes of said upstanding members and perpendicular to the plane of said dish-like members, and constricting means on each end of said bar members to bridge the distance therebetween and draw same together in clamping relation to said spine bar.

3. In a rack for supporting articles in a bath, a spine bar, at least a pair of article holders removably engaged along the length of said spine bar, clamping means to selectively fix the location of said article holders at any one of a plurality of points along said spine bar, a hook member on said spine bar for connecting said spine bar to an overhead line said spine bar comprising, a Welded assembly which includes a pair of elongate thin metal rectangular plates having facing flat surfaces juxtaposed and spaced one from the other with said surfaces parallel, a pair of elongate bar members of like material disposed between said plate members, each of said bar members being disposed along opposite elongate edges of said plate members, to form side walls for said spine bar whereby said resulting spine bar assembly is of elongate hollow rectangular configuration, said side walls of said spine bar assembly being shorter than said plate members so as to form flat resilient extensions at one end of said spine bar. said hook member being fitted between said extensions, and fastening means removably securing saidhjook member between said extensions,

41 In'a rack for supporting'articles in a bath, a spine bar, at least a pair oi article holders removably engaged along the length of said spine bar, clamping means to selectively for the location of saidarticle holders at any one of a plurality of points along said spine bar, a hook member on said spine bar for connecting said spine bar' to an overhead line, said spine bar comprising a welded assembly which includes a pair of elongate thin metal rectangular plates having facing flat surfaces juxtaposed and spaced one from the other with said surfaces par-' allel, a pair of elongate metal bar members disposed be tween said plate members, each of 'said bar members being disposed along opposite edges of said plate membars to, form, side walls for said spine bar whereby said resulting spine bar. assembly is of elongate hollow rectangular configuration, 'said article holders comprising dish-like members each having a central passageway therethrough, said passageway being-complementary in configuration with the cross-section of said spine bar so as to permit said spine bar assembly to pass therethrough, said clamping'means being fixedly secured to a surface of said dish-like member at the periphery of said passageway and comprising, a pair of L-shaped lug members disposed one on each side of said passageway, said lug members each having 'a flat base portion and an upstanding slightlyresilient back portion perpendicular to and integral with said base portion, said base portion beihg welded to the surface of'said article holder and said back' portions of said lug members adjacent the edges ofsaid passageway with their surfaces parallel to each other, a pair of elongate fiat fbar members secured to'the surface of the upstanding portion, of, each lug spaced fromthe edge of said passageway by said upstanding portion of said lug, and adjustable bridge means cooperative with the ends of said pair of bar members whereby force may be applied to shorten'the distance between said bar members, so as to bring said upstanding portion in surface contact with the flat surface of the plate members of said spine bar thereby clamping said article holders at any desiredlocation along the length thereof. V a H "5. In a plating rack structure which includes anelongate spine bar for mounting anarticle holder member thereon for supporting an article in a bath, the herein invention which comprises, an article holder comprising,

means secured to a surface of said body portion, said clamp means including upstanding lug members having spaced apart flanged 'means aligned one opposite the other adjacent opposite edges of said passageway with said space insubstantial registry with said passageway, and releasable tightening means connected between said flange means for selectively drawing said flange means one toward the other into frictional engagement with said spine bar with the latter extending through said passageway so as to adjustably mount said article holder thereon.

6. An article holder for supporting articles in a bath and adapted to be mounted along the length of a spine bar with, said spine extending therethrough, said article holder comprising at least a pair of individual holder's removably engaged in cooperative relationship along said length of spine bar, clamping means to selectively fix the location of said individual holders in any one of a plurality of points along said spine bar, each of said individual holders comprising, adish-like member having a central passageway therethrough, said passageway being complementary in configuration with the cross section of said spine bar so as to permit same to pass therethrough, said clamping means fixedly secured to a surface of said dish-like member at the periphery of said passageway, said clamping means comprising a pair of L-shaped lug members disposed one on each side of said passageway, said lug members each having a fiat base portion and an upstanding slightlyresilient back portion perpendicular to andintegral with said base portion, said base portion being fixedly secured to the surface of said individual holder and said back portions of lug members being adjacent the edges of said passageway with their surfaces parallel to each other, a pair of elongate fiat bar members secured to the surface of the upstanding portion of each lug spaced from the edge of said passageway by'said upstanding portion of'said lug, and adjustable bridge means cooperative with the ends of said pair of bar members whereby force may be applied to shorten the distance between said bar members so as to bring said upstanding portion in surface contact with the fiat surface 'on said spine bar, thereby frictionally clamping said individual holders at any desired location along the'length of said spine bar.

References Cited in the file of this patent OTHER REFERENCES Metal Finishing, June 1956 (vol. 54), page 23.

Claims (1)

1. A RACK FOR SUPPORTING ARTICLES IN A BATH COMPRISING AT LEAST ONE PAIR OF DISH-LIKE METAL MEMBERS EACH HAVING A PLURALITY OF RADIALLY EXTEENDING FINGERS THEREABOUT, AN ELONGATE METAL SPINE BAR, EACH DISH-LIKE MEMBER HAVING A PASAGEWAY IN THE CENTRAL PORTION THEREOF HAVING SUBSTANTIALLY SIMILAR CONFIGURATION AT THE CROSS-SECTION OF SAID SPINE BAR THEEREBY ALLOWING PASSAGE OF SAID SPINE BAR THERETHROUGH, EACH OF SAID DISH-LIKE MEMBERS BEING REMOVABLY SECURED TO SAID SPINE BAR WITH THE FINGERS OF ONE METAL MEMBER ALIGNED WITH THE FINGEERS OF THE OTHER AND WITH THE TIPS OF FINGEERS OF ONE MEMBER SPACED FROM THE TIPS OF THEE FINGERS TO THE OTHEER, ADJUSTABLE CLAMPING MEANS FIXEDLY SECURED TO EACH OF SAID DISH-LIKE MEMBERS WHEREBY SAID DISH-LIKE MEMBERS ARE ADAPTEED TO BE ADJUSTABLY SECURED ALONG THE LENGTH OF THE SPINE MEMBER, SAID SPINE MEMBER COMPRISING, AN ALL-WELDED HOLLOW RECTANGULAR ASSEMBLY HAVING A PAIR OF ELECTRICALLY CONDUCTIVE RELATIVELY THIN SHEET METAL PLATE MEMBERS JUXTAPOSED AND SPACED ONE FROM THE OTHER AND A PAIR OF RELATIVELY THICK ELONGATE BAR MEMBERS INTERPOSED BETWEEN SAID PLATE MEMBERS AT OPPOSITE ELONGATE ELONGATEE EDGES OF THE PLATE MEMBERS AND SECURED THERETO BY WELDING, SAID PAIR OF PLATE MEMBERS EXTENDING LENGTHWISE A SHORT DISTANCE FROM SAID BAR MEMBERS AT ONE END THEREOF TO PROVIDE A PASSAGEWAY ADAPTED TO RECEIVE A CONNECTOR MEMBER DISPOSED BETWEEN THE PLATE MEMBERS AT SAID END OF SAID SPINE BAR, AND REINFORCING MEANS FOR SAID PLATE EXTENSIONS COMPRISING, OVERLAPPING PLATE MEMBERS SECURED TO EACH PLATE MEMBERS AT A POINT SLIGHTLY BELOW THE END OF SAID BAR MEMBERS AND EXTENDING PARTIALLY OVER THE LENGTH OF SAID EXTENSIONS.

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