US2392687A - Apparatus for electroplating wire - Google Patents

Description

Jan. 8, 1946. J. s. NACHTMAN V APPARATUS FOR ELECTROPLATING WIRE Filed Feb. 15, 1943 2 Sheets-Sheet l m M m Na M S n by m J M mm Q Q \fik v Q Q i o \E r 1 O wN MM M MN NM MM w\\m QM R v x M Q .w\

Jan. 8, 1946. A s: NACHTMAN 2,392,687

APPARATUS FOR ELECTROPLATING WIRE Filed Feb. 15, 1945 2 Sheets-Sheet 2 E 30a V v 27 x; 33 3a- E? W W W g 5.9 {29 301) 55 57 I A I m 50 ll 60 I l 2 Se my 5 1m SAZac/zimam Patented Jan. 8, 1946 UNITED STATES PATENT OFFICE arraaarosroa ELac'raorm'rmG wnm John's. Nachtman, Youngstown, Ohio A plication Fermi-r15, 1943, Serial No. 415,908

f1 Claims. (Cl. 204-206) The invention relates generally'to the electro-.

plating of wire, and more particularly to the-continuous electroplating of wire and the like to produce a uniform and adherent coating.

In the conventional practiceof electroplatin wire the plating anodes donot' completely sure round orencircle the wire, and are. located at a substantial distance fromsome parts of the wire in the plating solution. This arrangement requires a high electroplating voltage and tends to produce polarization at the electrodes, which not only sets up increased resistance to the flow of plating current, but causes evolved gas to ac-. cumulate on the surface of the wire, and such accumulated gas produces rough deposits in the.

coating which crack and peel oil-when thewire is sharply bent after coating.

- Moreover, in conventional practice ing eflect or the current on the solution and the wire, and consequently the rate of electroplating is correspondingly limited.

Furthermore, in conventionalelectroplating of wire, the wire is often reeved up and down a number of times during the plating operation, and

this requires added equipment which in the case: of heavy gauge wire is heavy and expensive both conditions, while circulating plating solution through thetubular anode at a rate calculated to maintain ideal plating conditions.

a It is therefore a general object of the present invention to providernovel apparatus and methods for e ectroplating wire, seas-to overcome all the disad antages present in 'prior practice.

A' more-speciflc object-isto provide for continuously electroplating wirewith-a minimum of electroplating voltage. i I

"Another object is' to provide for increasing the currentdensity which can be used in electroplating 1 wire and-thus produce a higher rate of electroplating. 3 l

' Another object is to'provide for substantially eliminating-polarization at the electrodes during the electroplating of wire. g -'A further'object is to provide an improved method and apparatus for electroplating wire in which the wire travels in a straight horizontal DathI I A still further object is to provide a high speed the current density which can be used is limited by the heateconomical method of producing electroplated wire having a uniform, fine-grained and adherent coating which will stand severe bending without peelingor cracking.

These and other objects which will be apparent from the following description are accomplished the accompanying drawings and herein described and claimed.

Referring to the drawings I Figure 1 is a diagrammatic side view on a small scale of a complete wire electroplating line embodying the present invention;

Fig. 2 is an enlarged somewhat'diagrammatic longitudinal view, partly in section and partly in elevation, of a preferred embodiment of one oi. the units for carrying out the electroplating step of the invention;

4-4,Fig.2; and

" described as applied to the electroplating of steel wire with zinc, but it is obvious that within the- Fig. 3 is a transverse sectional view ason line 3-3, Fig. 2;

Fig. 4 is a transverse sectional Fig. '5 is a transverse sectional view-as on line 55, Fig. 2.

Similar numerals refer to similar parts throughout the drawings.

For convenience, the invention is shown and scope of the appended claims the invention is applicable with slight modifications to'the electroplating of wire with a variety of other'metals.

For example, in plating wire with a heavy deposit or copper, it is advantageous to use a. copper cyanide strike in a section of my novel plating apparatus, followed by a water rinse; and then to use an acid copper electrolyte in one or more ad-.

ditional sections of my novel plating apparatus.

Also, for obtaining very heavy plating deposits with relatively fine-grained structure, it is desirable' to plate alternately from alkaline and acid.

electroplating solutions inseparate sections or 'units of my novel plating apparatus with thorough water rinsing between sections.

Referring first-to Figure 1, wires continuously to the electroplating line in a well known manner, as by motor driven feed rolls 1,

' which pull the wires from a plurality of pay-off The wires are pulled continuously at substan view as on line W are fed or chambers by suitable partition walls.

convenience, I have shown in Figure 1 all of the tially constant speed from the feed rolls l6 through the rest of the apparatus by the pulling rolls I 1, and other rolls in the line may be synchronously driven if desired. When. a coil from reels 8 or 9 is completely paid out, the feed rolls I are temporarily stopped while the end of a new washing and drying, and these steps may be performed in separate compartmentsor units, or

asaaea'r 3| mounted in angular supporting arms 32 which are pivoted at the elevation of the wires in in-, sulated bearings 33 secured to the sides of the tank 21. The upper ends of the arms 32 are adjustably secured preferably by bolts 34 passing through slots in the arms, to brackets 35 mounted on the tank 21 and insulated from the arms 32 as indicated at 36. If desired, the brackets 35 may be made of insulating material.

Thus, the pressure of the contact rolls on the wiresw pan be adjusted by loosening the bolts 3.4'fan'd rotating the arms 32 about the pivots 33 to move" theiolls 23a and 23b toward or away 3 from the wires. As indicated diagrammatically some or all of the steps may be performed in one 1 continuous compartment separated into sections For treatment steps except drying as being performed in'Fig.,2, the negative terminal of a D. C. generator 'Gconnected to the arms 32 by a current conductor 38, which may be conveniently connected to the nuts 39 on bolts 34. Thus current passes from the generator G through the arms 29 32 and contact rolls 23a and 23b to the wires W.

in a series of sections, or chambers embodied in' one unit.

The wires W pass from the feed rolls l6 preferably successively through a cleaning section i 8, rinsing section l9, pickling section andrinsing section 2|. high pressure water sprays and the cleaning and pickling sections may be electro-chemical units in which the cleaning and pickling solution is jetted against the wires by nozzles electrically connected to one, side of a generator while the 7 wires are electrically connected to the other side,

The rinsing sections may include 40 is rotatably mounted in longitudinally spaced bearings indicated generally at 4| and supported on the floor of the tank 21. The bearings 4i may each include a bearing cap 42 of current conduct- 27, 1945. However. any conventional cleaning,

rinsing and ickling treatment may be used which will deliver the wires to the electroplating sections or units free of oil, dirt, oxides or other foreign matter.

The electroplating section preferably includes a plurality of identical plating units. two such units being shown generally at 22 in Figure 1. by wav of example. Preferabl at both ends of each unit 22.' the wires W pass through pairs of contact rolls 23, later to be described in detail. Following the electroplating treatment. the wires are suitably rinsed in section 24. which may have high pressure waters rays if desired. and then pass through a dryer and through the pulling rolls l1 to winding reels 28.

are desired. they can be substantially the same as the rinsing sectionsor units' I 9, 2i and24.

ing metal such as nickel which will withstand the corrosion eiiect of the plating solution and each cap 42 may have arcuate portions 43 for fitting around the anodes 40, with laterally projecting end flanges 44. 1

The bearings 4 l also include bearing inserts 45 of insulating material such as micarta for fitting under the anodes. 40 and supporting the weight thereof. The bearing inserts 45 are in turn suitably supported from the door of the tank-by means such as flanged plates 46 and 41 which are provided with apertures 48 and 49 respectively to allow free circulation of plating solution con- Referring now to Figs. 2 to 5 inclusive, one of v the electroplating units 22 is shown mounted in a tank 21 having a lining 28 of rubber or other ing means such as a motor (not shown).

ing arcuate grooves 29 for contacting the upper and lower surfaces of the wires W as they pass between the rolls. The roll shafts 39c and 301) may be journaled in current conducting bearingsincludes a nozzle 60 of insulating material such tained in the tank' 21.

Means for yieldingly clampingthe bearing caps 42 downwardly against the anodes 40 preferably includes studs 50 secured in plates 46 and projecting upwardly through flanges 44 of the bearing caps. Nuts 5| on the upper ends of the studs 50 compress springs 52 against the flanges 44 to urge the bearing caps downward against the anodes 40. As shown in Fig. 2. the positive side of the generator G is electrically connected by a conductor 53 to the anodes 40 through the bearing caps. .Studs 50 are insulated from plates 46 by suitable insulation indicated at 50a,

Means for rotating the anodes 40 for subjecting every part of the wire surface within the anodes to the same lectrodic conditions, preferably includes gears 55 one secured on each tubular anode 40, as by a key 56. The gears 55 mesh with each other as shown in Fig. 4, and one gear is driven by a pinion 51 mounted on a drive shaft 58 which is operatively connected to suitable driv- Gears 55' and pinion 51 are preferably of insulating material such as micarta, to prevent passage of th plating current therethrougli.

-Means for directing plating solution into the front ends of the anodes 40 and for guiding the wires in paths axially of said anodes, preferably along the wire which would otherwise produce as porcelain mounted at the front end of .each

anode. .Each nozzle 60 preferably has a curved passageway 6| receiving a vertical supply pipe 62 at its upper end and discharging into th anode through an annular boss portion 63 which loosely tits in the front end of the anode. A guiding aperture 64 for the wire W intersects the passage 6| and is coaxial with the anode 40'. Preferably a post or the like 65 supports each nozzle 60 from the floor of the tank.

At the rear or exit end of each anode 40 is mounted a discharge nozzle 85 of insulating material such as porcelain having a curved passageway 61, preferably of smalle cross section than inlet passageway 6| leading from an annular boss portion 68 loosely fitting in the discharge end of the anode, and the passageway 61 discharges vertically downward into the tank. A guiding aperrough deposits of the plating.

Accordingly, the present invention provide a high speed and economical way of producing electroplated wire having a uniform plating of high quality which will not peel or crack when ture 69 for the wire W intersects the passageway 81 and is coaxial with the anode. A perforate support 10 may be provided for supporting the nozzle 68 from the floor while permitting plating solution to flow out of the nozzle into the tank.

Preferably, a solution slinger disk H is mounted on each end of each of the anodes 40, to prevent an excessive amount of plating solution from reaching the gears 55 and bearings II.

In the operation of the electroplating units, as

I the wires W pass continuously therethrough, plating solution is maintained in the tank 21 at a suitable level such as indicated by the dot-dash line L, and is pumped from the tank through the conduit 12 by pump 13 through the heat exchanger indicated diagrammatically at 14, where the solution temperature is adjusted to the desired degree. From the heat exchanger 14 the solution is circulated through conduit 15 by suitable connections (not shown) to the inlet pipes v 62 whence it flows through the rotating anodes 40 and back into the tank.

Any good commercial coating solution for electroplating the desired metal may be used. For example when plating zinc on steel, the following solution is very satisfactory:

While the plating solution is circulating through the rotating anodes, electric current flows from the generator G through the contact rolls 23 to the wires W, and from the wires through the plating solution to the rotating anodes and back to the generator.

If the anodes 40 are made of a metal which is insoluble in the plating solution. the metal con tent of the plating solution must be replaced as it is plated out of solution; whereas if the anodes are made of a metal which is soluble in the plating solution, then the anodes must be replaced as they are dissolved. v

Due to the fact that the tubular anodes are closelyand uniformly spaced from all sides of the wires at all times and the anodes are constantly rotating to provide uniform anode-conditions all around the wire, a relatively low electroplating voltage may be used with a. high current density to give an extremely high plating efliciency; and

a uniform, adherent and fine-grained coating is produced on the wire. The circulation of the platingsolution through the rotating tubular anodes provides for a minimum of polarization and hence substantially eliminates the accumulation of gas the wire is bent sharply.

The fact that the wire travels at a high speed in a horizontal pathmakes it possible to plate heavy gauge wire in relatively light equipment,

path as the advantages thereof are also present regardless of the position of the anodes. When the anodes are not in a horizontal path it is necessary to provide rolls for guiding the wires in the desired path to maintain the wires concentric with the anodes.

I claim:

1. Apparatus for continuously electroplating wire and the like including a rotatable tubular electrode, means for rotating said electrode, means for passing wire continuously longitudinally in one direction through said electrode axially thereof, means for circulating electroplating solution through said tube from one end to the other, and means for passing electroplating current from the wire through said solution to said tubular electrode.

2. Apparatus for continuously electroplating wire and the like including a hollow cylindrical anode, means rotatably mounting said anode, means for rotating said anode, a nozzle mounted at one end of said anode for delivering platin solution into said anode, a nozzle mounted at the other end of said anode for discharging plating solution therefrom, means for continuously moving wire in one direction th ough said anode axially thereof while said anode is rotating, means for supplying plating solution to the delivering nozzle and means for passing an electroplating current through said solution between the wire and said anode.

3. Apparatus for continuously electroplating said nozzles having means for guiding said moving wire axially of said anode, means for supplying plating solution to the delivering nozzle. and means for passing an electroplating current through said solution between the wire and said anode.

4. Apparatus for continuously electroplating wire and the like including a nozzle for delivering plating solution, an axially aligned nozzle longitudinally spaced from said delivering nozzle for discharging plating solution, a hollow cylindrical anode journaled at its ends on said nozzles, means for rotating said anode, means for continuously moving wire longitudinally through said anode in one direction while said anode is rotating, means for circulating plating solution from the discharging nozzle to the delivering nozzle, and means ior passing electroplating current from the wire through said solution to said anode.

5. Apparatus for continuously electroplating wire and the like including a hollow cylindrical anode, adjustable means rotatably mounting said anode, means for rotating said anode, means for continuously passing wire longitudinally in one direction through said anode axially thereof while said anode is rotating, means for circulating electroplating solution through said anode from one end to the other thereof, contact rolls engaging said wire, and an electric current generator connected in circuit with said contact rolls and said anode for passing electroplating current through said solution.

6. Apparatus for continuously electroplating wire and the like, including a hollow cylindrical anode, means rotatably mounting said anode, means for rotating said anode, a nozzle mounted at one end of said anode for delivering plating solution into said anode axially thereof and having a wire guiding opening axially alignedwith said anode, a discharge nozzle mounted at the other end of said anode for discharging plating solution therefrom and having a wire guiding-- opening axially aligned with said anode, means for continuously moving wire in one direction longitudinally through said nozzle guiding openings and said anode while said anode is rotating, and means for passing an electroplating current through said solution between the wire and said anode. 1

7. Apparatus for continuously electroplating wire and the like, including a. hollow cylindrical anode, means rotatably mounting saidYanode, means for rotating said anode, means for continuously passing wire longitudinally in one direction through said anode axially thereof while said anode is rotating, means for circulating electroplatingsolution through said anode from one end to the other thereof, upper and lower contact rolls engaging said wire, means adjustably mounting said contact rolls for movement toward and away from said wire, and a'generator connected in circuit with-said contact rolls and said anode for passing electroplating current through said solution between the wire and said anode.

JOHN S, NACHT'MAN.

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