US1590608A - Insulated electrical conductor and the like - Google Patents

Description

E. TAYLOR INSULATED ELECTRICAL CONDUCTOR AND THE LIKE June 29 1926.

Original Filed March 11 V Qwbantoz 6M M W35, W1 MM! Patented June 29, 1926.

UNITED STATES 1,590,608 PATENT OFFICE.

EDWIN TAYLOR, OF BROOKLYN, NEW YORK, ASSIGNOR TO TAYLOR LABORATORIES, IN 0., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

INSULATED ELECTRICAL CONDUCTOR AND THE LIKE.

Original application filed March 11, 1920, Serial No. 864,980. Divided and application filed June 17,

1924, Serial no. 720,520. Divided and this application filed March 18, 1926. Serial No. 95,802;

My invention relates'to improvements in insulatedelectrical conductors and the like. The main object of the invention is to provide an electrical conductor with an improved insulation'of organic material. The invention, however, may also be used for coating other objects than electricalvconductors, for example ribbons, sheets, etc. 01' various materials. This application is a division of my prior application Ser. No. 7 20,520 filed June 17, 1924 which in turn is a division of my prior application Ser. No. 364,980 filed March 11, 1920.

Further and more specific objects, features and advantages will more clearly appear from the detail description given below taken in connection with the accompanying drawing which forms a part of the specification.

The drawing, partly in vertical section, illustrates more or less diagrammatically an apparatus adapted to put the main features of the improvements in one form.

According to my invention in its preferred form, I insulate or coat the conductor or other body with a layer of cellulose. I preferably do this by making a suitable solution of cellulose, applying a layer of this to the wire conductor or other body and removing the solvent constituents from cellulose, leaving a homogeneous integrally continuous layer of cellulose on the body. I preferably remove the solvent constituents by electrolytic action. For this purpose I preferably dissolve the .organic material such as cellulosic material in a solution of zinc chloride ora solution of hydrated cupric oxide in concentrated ammonia. By such solution of the cellulose in zinc chloride or the cuproammonia the cellulose is converted from the cellular or fibrous condition to a, colloidal state. I preferably use a solution which is relatively concentrated and thick, and apply a suitable layer thereof to the body to be coated and then subject the cellulose solution on the body to electrolysis whereby the cellulose is' deposited more solidly upon'the body to be coated which may serve as the anode, and the copper or zinc as the case maybe, is deposited on a cathode, the'chlorine or ammonia being given ofi in gaseous form. Both the gas so given off, as well as the metal deposited on the cathode,'may be recovered for .re-use.

Referring to the drawing which illustrates an apparatus adapted for use in coating or covering rods or filaments of cellulose as well opposite wall of the tank 10 is a hollow fitting or nozzle 43, provided with a bore substantially the size of the objectto be coated and placed central with the bore of nozzle 12.

The nozzle 12 projects through the wall of a second tank 20, of any desired length, and

' fitted at its further wall with a'stuifing box having a central perforation 47, approximately of the diameter of the coated rod or wire. A vent pipe 33 is placed at the top of tank 20, for the removal by suction of gases released or generated during operation.

Below the level of the liquid in tank 20, and central with nozzle12 and stufiing box 47, is suspended a tubular electrode 37 split lengthwise to facilitate removal,. and provided with electric connections 38, the tube be ng a cathode while in useuBeyond tank 20 and communicating with it-bythe stuffing box 47, is a third tank 50 containing a roller 48 at its further end. V

The object to be coated, for instance a wlre 46 on a reel 45, is led through nozzles 43 and 12, through gu de piece 44, orifice 4, electrode 37, stuffing box 47, under roller 48, and to a reel 51, situated outside of tank 50 and so driven that it may place the wire under enough tension to draw it from the reel and through the apparatus. Tank 10 is now filled with a viscous, concentrated monia, or inthe case of silk in nickel-ammonia alone or in a mixture of both cupro.

' solution of organic material such as cotton or silk dissolved-for example in cupro-aman electric current is passed through the wire 46 by means of a contact shoe 28, and

a conductor 29, connected to the positive pole of a source of electricity. The wire 46 while passing through the tubular electrode 37, becomes an anode and 37 a cathode. cellulose issuing between the wall of the orifice 4 and the centrally located-wire 46 is caused to flow at a slower speed than the wire and is drawn or stretched thereon in a uniform coating of any desired thickness the flotation effect of the bath materially preventing flow of the viscous solution after eaving nozzle 12 and before the cellulose has been finally deposited on wire 46 by the travel of the coated wire through the oath means of the current passingduring passes through the -stufling box 47 filling the bore thereof and so preventing the water in tank from mixing with the acid liquid in 20 or vice versa. The coated wire 49 is now well washed during passage through tank 50 passes under under ide-roll 48, and to reel 51, it now being rea y for drying or for further desired operations. It is obvious that in place of one wire or rod passing through orifice 4, any number of wires maybe passed in parallel each bin separated from its neighbor by coating 0 cellulose, etc., and the whole enclosed in a like coating of any desired thickness, Furthermore the nozzles and apparatus may be so constructed and placed that a twisted or v cable effect may. be imparted to the wires during coating.

The above process after drying, etc., results in a tough, elastic, transparent coating which is substantially impermeable to oil and of any thicknessor color, etc., desired,

firmly adherent to the wire and of a-high' di-electric-strength. The coating resulting ing the "covered wire as it, leaves t 50 through successive apparatus of the. e kind, the coated wire still wet passi in at. a nozzle similar to 43 but of larger re to from the above described. process is substantially pure cellulose and the cellulose is practically. uncombined, that is, 'it is not combined with esters or other radicals to form compounds such as xanthates, nitrates, and the hke. Successive coats of the same or different material may be given by assaccommodate the increased diameter.

' In the application of thislproc'ess and its modifications as applied to isilk advantage may be taken of the fact that silk will dissolve in nickel ammonia solution, while cotton will notyalthough cupro-aminonia dis- The,

solves both. Mixed silk and cotton waste goods, etc., may be separated and'rendered of increased commercial value by first'treating the mixed material with nickel-ammonia whereb the silk is dissolved and removed from t e cotton by filtration.

The cotton may now be dissolved in cupro-ammonla and 7 As to the process in general the utmost care' sliould be exercised to avoid all dustand dirt. The solutions must be carefully filtered and dirt kept out afterward. 'All the apparatus should be closed in wherever possible. The water employed for making up the solutions should be distilled or at any rate contain a minimum of mineral salts and should be free from carbonic acid gas if a fine filament or a perfectly transparent product is desired.

The stren h of the acid water must also be kept wit in reasonable limits although this is eas on account of the large volume in the tanli compared to the amount circu-- slowly. This acid water should also e kept free-from grosser impurities and from CO I prefer to use nitric acid as its ultimate product under electrolysis is always amcount of the many variations of the generalprocess, A direct current is preferable; .a pulsating current in one direction gives good results but takes atlonger time. The problem is an electro-chem cal one andthe rate of deposition of both cellulose and metal s a function of the amperage rather than of voltage. .For instance, in the electrolysis of cellulose dissolved in cupro-ammoma, I have used currents of 110 volts and a current densityv of amp. per sq. inch of anode surface, while almost the same result may be obtained with 1.8 .volts and of an amp. per sq. inch, although the time required is longer. .In geneiah'only enough 'lated, changes in concentration takin place amperage should be carriedto secure a reasonably adherent deposit on the cathode,.

of I the metallic .solu t1 on c-onsttu1uent pinilo ed.- If thecurrent' zafef isnn y ra se it spongy deposit .of fif'tal ifp'rms which s apt to fall into the bath, adhere to the material being treated and otherwise cause trouble, while at the same timethe bath overheatsand more current passes than is required. Contrary to this a heavy amper age favors the deposition of cellulose. For cathodes a metal similar to the one used in the solvent, copper, nickel, zinc, etc, should be employed. With a little attention to the amperage passed all these metals me be deposited in a somewhat spongy'condi-- tion and while adhering well to the cathode, may be easily scraped therefrom in a condi-. tion to be readily re-dissolved for the preparation of new solutions.

, For dissolving the organic'material, cellulose, silk, etc., if the solution is to be an ammoniacal one, I prefer to saturate 'ammonia water, free from. carbonate of ammonia, etc.,- withhydrated cupric or nickel oxides The solutions are filtered through fibrous, intro-cellulose, cooled to about 40 F. and saturated with the material to .be dis-' solved in suitable mixin machines. The

amount of material d1ssolved' depends largely upon the fibre etc. used varying some-whatlwith each diflerent qualit or grade of the same kind of material. ome' raw cottons for. instance willcompletely dissolve in, the proportion of l lb. cotton to 20 lbs. of cupra, while with other varieties,

' l lb. cotton to 35 lbs. solution is the best that can be done. When using zinc chloride,

I employ a saturated solution of'the C. P. salt indistilled water, these solutions. being-- even more sensitive to im urities than the ammoniaones and" more ifiicult to handle and recover;

.. After solution is complete the viscous mass is allowed ,to stand for-aboutj24 hours,

during which" time-it becomes m'uch more fluid and may be forced through a filter by means of pressure. A-fine 'sandbed on top ofa layer of nitro-cotton, which in turn 1s supported by a fine wire screen is quite satisfactory.- When desired the solutions are now concentrated by centrifugal action.

' At this stage. other ingred entsmay be added to the" more or less-fluid solution. .For ;instance,'if a saturated solution of cotton, or

other cellulose in cupro-ammonia is employed itis evident that if more cellulose,

say in a fibrous but rather finely divided state be. added, this latter addition will be' practically unaffected by the solution but it will increase the viscosity of the mass, necessitate a h1gher pressure to force it through the nozzles or-dies. and will materially reduce the shrinkage or'drying, the result be-.

sire to be limited to such details and forms,

since many changes .and modifications may be made and the" improvements embodied in widely difierent forms without departing from the spirit and see c thereof in their broader as ects; hence desire to. cover all forms coming within the language or scope of any one or'more oftheiap ended claims.

. What I claim as new and, 'esir'e to secure by Letters Patent, is: p

1. An insulated electrical conductor ,com-

prising. aconductin" wire with an insulating coating of su stantiall'y non-fibrous, structureless and uncombined cellulose thereon, said coating being substantially transparent, homogeneous and substantially con- .tinuous throughout and substantially impermeable to oil.

2; A body having thereon-acoatingof substantially pure cellulose, the cellulose being substantially noncellular and structuretially continuous coatingsubstantially impermeable to oil.

In testimony whereof I have signed my name to this specification.

EDWIN TAYLOR.

less and uncombined and forming a substan' Y

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