US340397A

US340397A - Edwaed webton

Info

Publication number: US340397A
Authority: US
Publication date: 1886-04-20
Anticipated expiration: 1903-04-20

Description

I (NOM0de1.)-

E. WESTON.

MANUFACTURE OF CARBON CONDUCTORS FOR INCANDESCENT ELECTRIC LIGHTS.

No, 340,397. C Patented Apr. 20, 1886.

UNITED STATES PATENT 'QFFICE;

EDWARD WESTON, OF NEWVARK, NE? JERSEY, ASSIGNOR TO THE UNITED STATES ELECTRIC LIGHTING COMPANY, OF NEW YORK N. Y.

MANUFACTURE OF CARBON CONDUCTORS FOR INCANDESCENT ELECTRIC LlGHTS.

SPECIFICATION forming part of Letters Patent No, 340,397, dated April 20, 1886.

Application filed September 9, 1885. Serial No. 176,552. (No model.) I

To all whom it may concern:

Be it known that I, EDWARD WEsToN, a subject of the Queen of Great Britain. and a resident of Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in the Manufacture-of Carbon Conductors for Incandescent Electric Lamps, of which the following is a specification, reference being had to the drawings accompanying and forming a part of the same.

I will first describe the general nature of the method or process involving my improvements, and then indicate more particularly the special features of novelty which I here claim.

I prepare from a suitable carbonizable material straight strips or filaments of carbon without enlargements of any kind. I prefer to use the material now known as tamidine, though others maybe employed for this purpose.

It is desirable, and, in fact, necessary to the economical and practicable manufacture of the lamps, that the ends of the carbon to which the supporting-wires are joined should be somewhat enlarged, and I prefer for many rea sons to form these enlargements by electrically heating the conductors near their ends only in a hydrocarbon vapor or liquid; but I have found that to simply place the carbons as they are taken from the carbonizing muffle or retort in the stub-forming apparatus yields very poor results. Oarbons made in this way seem to be imperfect from the fact that the certain gases which seem to be retained by the carbon are'not driven off. To remedy this I mount the carbons, just as they are when taken from the carbonizingmuffle, in a temporary receiverand by an elec tric current I raise them to a very high incandescence. To do this without injury to the carbon the air must be very perfectly exhausted from the receiver, or, what is much easier and equally effective, a small quantity of a hydrocarbon or similar vapor should be introduced after roughly exhausting the receiver. The degree of incandescence to which the carbons are thus raised should be somewhat higher than that at which they are expected to run under normal conditions of use, and it is only necessary to maintain them so for a few seconds. In this treatment all but the extreme ends of the carbons are rendered incandescent, and the retained gases driven oft. The carbons are then removed and placed in any convenient form of apparatus by which a small portion of each end is rendered incandescent in a vapor or liquid that forms on them a deposit of carbon, and in this way the enlarged ends or stubs are formed. The eX- treme ends, which have been in the clamps in both of the devices above described, and consequently not raised to a very high temperature nor sensibly coated by the carbon de- 6 5 posit, are broken off before the carbons are mounted or subjected to any other treatment.

In the drawings I have illustrated the various steps or stages of this process.

Figure 1 represents the carbon before treatment. Fig. 2 is a side elevation of an ordinary form of apparatus for raising the carbon to incandescence. Fig. 3 is an apparatus for forming the stubs, and Fig. 4 is the carbon witht-he enlarged ends or stubs.

The apparatus in Fig. 2 is a simple receiver connected by a tube, A, with an air-pump. Under the glass B are clamps G, in which a carbon is placed, and after the air has been exhausted and a small quantity of gasoline or 80 similar vapor admitted it is raised to a high point of incandesceuce. The carbon is then placed in a receptacle, D, containing petroleum or gasoline or the like, and held by clamps E, to which the electrical connections are made, '85 as indicated by the dotted lines. When the enlargements F have been formed, the endsf are broken off and the carbon mounted in a lamp or subjected to whatever treatment may be considered desirable or necessary. By this 0 process the entire carbon undergoes an operation by which the retained gases are expelled beiore the deposited ends are formed.

The carbons are standardized-after the ends are formed by mounting them in a receiver 5 similar to that shown in Fig. 2, containing a rarefied hydrocarbon vapor, and heating them by a currentuntil by the deposition of carbon their resistance is brought to a certain point. This process, which is commonly known as too treating, is effected to small degree by the l may be contained in thecarbon, but to compreliminary process herein described for expelling the occluded gases. The two steps plete a process of carbonization which no other process of which I an: aware is capable of fully are, however, distinct, as in the real process effecting.

of treating the temperature, at leastat the start, is very much lower, and in the firstnamed step the vapor is only employed in or der to avoid the use of a high-vacuum apparatus.

I have found that carbons of rior qualities are produced in the way above f described.

It has been usual heretofore to form the ends or stubs by the deposition of carbon to lower the resistance of the carbons by heating them in a hydrocarbon vapor, and to expel the gases from the carbon by raising it to a high degree of incandescence during the process of exhausting the lamps or while the lamps are on the pumps; but this process in volves the novel features of raising for ashort time the carbons to high incandescence before either the ends are enlarged or the carbons I standardized. treatment is not only to expel such The probable effect of this, gases as I What I claim is 1. The method or process of manufacturing carbon conductors, which consists in raising the carbons to high incaudescence by an electric current and then heating the carbons at greatly supeor near the ends only in a hydrocarbon or similar vapor or oil, to form enlarged stubs thereon, as set forth.

2. The method or process of manufacturing carbonconductors, which consists in raising the carbons to high incandescence by an electric current, then heating the carbons at or near the ends only in a hydrocarbon vapor or oil, to form enlarged stubs thereon, and then heating the entire carbons in a similar vapor until their electrical resistance is brought to the desired point, as set forth.

EDWARD WESTON.

\Vituesses:

FRANK N. CRANE, FRANK H. KING.