US2109975A - Anode - Google Patents

Description

Patented Mar. 1,1938

UNITED STATI-:s

PATENT ,oi-*FICE Wellman Bronze and Al nminum Company,

Cleveland, Ohio, a corporation of Ohio Application June 18, 1936, Scrlal'No. 875,932

I Z Claims.

My invention relates to anodes for use in electroplating, and I particularly utilize the same in chromium electroplating. The objects of the invention are to provide an anode which will not readily'be broken or injured, the parts of which will not be adversely affected by the constituents of the electrolytic bath, which hasan even and uniform wear in service, which may be economically manufactured and used and conveniently in use through the provision of a great number of throws or discharge lines for the current. i 'I'he annexed drawing and the4 following description set forth in detail certain means embodying my invention, such means constituting, however, but one form in which the principle of the invention may be embodied.

In said annexed drawing: u Figure 1 is a vertical section of ihore or less conventional assembly of a treating tank, elec# trolytic bath, and suitable electrical connections, for electroplating, in which my invention serves as the anode;

Figure 2 is an venlarged side view of the improved anode of Figure 1 with a section of the bus-bar from which the anode depends;

Figure `3.is a face view of the elements shown in Figure 2;

Figure 4 is a perspective view of the anode shown in Figures 2 and 3 detached from the supporting bus-bar; 1

Figure 5 is a fragmentary enlarged longitudinal section, showing the upper part of the anode,

l this view particularly illustrating means for connecting the anode body to a hook by means of which the `anode is dependingly supported from `the supporting bus-bar; and

Figure 6 is a transverse section, taken in the plane indicated-by the line 6 6, Figure 5.

Referring particularly to the annexed drawing in which the same parts are indicated by the same respective numbers in the several views, my improved anode I, preferably a castv4 member, is of the' herring-bone type and, as used in practice, is shown in Figure 1, wherein two of the anodes I are shown, suspended in a suitable -electrolytic bath-3 serving as the plating solution, preferably a mixture of chromic and sulphuric acids for chromium plating, the bath 3 being contained in a suitable treatment tank 2 having an inside lining of sheet lead. The article t to y be plated, is suspended in the bath 3 by a hook 6 upon a bus-bar 5 mounted upon thf conductor 'I and thereby the article 4 is connected in cirl f cuit with the negative pole of a source of electric applied for use, and which will be very effective (ci. 20s- 4) f current. The anodes I are dependingly support-` ed by the bus-bars 8 suitably mounted upon thev tank 2 and in turn supporting the ,conductor 9 whereby the anodes I are connected with the positive pole of the current source. 5

My improved anode I comprises a herringbone body or stem II having a plurality of (ippo-4 sitely-disposed spaced laterally-extended ns I2. The body II and ns I2 are'ilatplane members with their adjacent sides substantially relatively 10 right angular so that there are provided six sharp edges I3 on each arm I2, and two sharp edges I4 on the body member II between adjacent arms I2, thus to provide the anode I with a compara-,- tively great number of electric throws or dis- 15 charge lines, whereby the anode has great capacity. Also, such construction' permits the use of a comparatively light anode compared to its capacity, and also provides even and uniform wear as the anode is consumed. 5 20 'I'he supported end of the anode I is of bifur- 4 cated formation, providingtwo legs I5 whose terminal portions I6 are enlarged and formed 4with deep sockets I6. However, the depth of the sockets I6' is not as great as the length of 25 the enlargements I6 so that a strengthened section 23 is formed between the main portion of the leg I5 and the bottom'of the socket I6'. This strengthened section 23 is for the purpose of providing against a break occurring in this section 30 by reason of the weight of the anode. and prefabiy, this section 23 is of llet formation 23'.

The anode I is supported upon the bar Il by means of hook-like members Il having stems 20 which are secured within'the sockets I6 of the 35 enlarged portions I 6 of the legs I5. These hooks I'I have a contacting eld which is substantially square in cross-section, and within this field the actual contacting areas, consist of three lines of contact, this arrangement being afforded by the 40 fact that the hook II consists of a' three-sided member whose adjacent sides I8 are substantially relatively right angular and are each provided with an inside plane face I8 by which is provided a line of contact I9 with the round sup- 45 porting rod 8.

In order that liquid seepage may be avoided at the joint where the stem 2Il enters the socket I 6', the upper ends of the,enlargedmember I6 are drawn in, in beveled formation 2|, and 50 the extreme upper edges of these beveled parts .2l are secured to the adjacent portions ofthe stem 20 by fused joints 22. Inv order to reinforce the hooks Il, which preferably are formed of copper, and thus require protection against 55 2 i acids ,and acid radicals. particularly at the level of the depositing solution, I preferably face these l hooks I1 with a coating of tin and lead. preferably 80% tin and 40% lead. The anode proper. consisting of the stem II, arms I2, and legs I5-I, consists of an alloy, of which the preponderant portion is lead, preferably about 94% lead,` mixed with a minor portion of metal of the order of antimony or tin to the amount of substantially 6%.

Thesections I8 of the snode I are preferably c ast around the hook stems 20, and a secure connection between the sections Il and stems 2l eifected by first roughing up the outer surface of the stems 20, as by providing notches 24. Figures 5 and 6. The tin-lead coating of the stems 20 assists in providing, or may entirely provide, the desired leak-proof joints 22, inasmuch as the casting of the anode will bring the coating to a brazing temperature.

What I claim is:

1. An anode for electroplating comprising a flat body member having longitudinally-spaced laterally-extended arms, adjacent sides of said body member and arms being in substantially right angular relation, said body member being formed with an enlarged and socketed end portion, and a supportingimember secured at one end in the socket of said, body end portion and formed at the other end with an open-ended hook having a support-engaging face substantially square in cross-section whereby to provide thrnee lines of contact with a round main -sup- PO 2. An anode for electroplating comprising a supporting member having an end portion formed on its exterior surface with a plurality of spaced notches, and a herring-bone body member formed with an enlarged end portion cast around said notched end portion of the supporting member and secured to the latter by a drawn-in beveled terminal fused to the supporting member.

CHARLESF. OTT.

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