Brush Electric Co. v. Fort Wayne Electric Light Co.

• Decision Date: 24 December 1889
• Citation: 40 F. 826
• Parties: BRUSH ELECTRIC CO. v. FORT WAYNE ELECTRIC LIGHT CO. et al.
• Court: United States Circuit Court, District of Indiana

40 F. 826

BRUSH ELECTRIC CO. v. FORT WAYNE ELECTRIC LIGHT CO. et al.

United States Circuit Court, D. Indiana.

December 24, 1889

M. D. &amp L. L. Leggett and H. A. Seymour, for complainant.

R. S Taylor, for defendants.

GRESHAM J.

This suit is brought for alleged infringement of letters patent No. 219,208, granted to Charles F. Brush, September 2, 1879 for improvement in double carbon electric lamps of the arc type. Brush assigned the patent to complainant before suit was brought.

When two ordinary, pointed, carbon sticks are in contact in an electric circuit, the circuit is closed, and the current freely passes through the carbons, without the production of any appreciable amount of heat or light at the point of contact. If, however, while the electric current is passing through them, the carbons are slightly separated, the current will continue to flow, and in crossing or leaping the small space intense heat and light will be produced. This is known as the electric arc lamp, and the one generally used for illuminating large buildings and halls, and for lighting streets. The incandescent electric light is produced by causing a current of electricity to pass through a filament in a glass bulb, from which the air has been exhausted. In its passage the current encounters great resistance, and, as a consequence, the filament is heated to a degree producing a bright, white light throughout its entire length. This light is well adapted to use in-doors. As early as 1810, Sir Humphrey Davy, with a battery of 2,000 cells, succeeded in producing an arc light between two horizontal charcoal pencils, insulated, except a small portion at their ends; but, owing to the rapid combustion of the soft points, the great cost of the battery, and the short duration of the light, it was of no practical or commercial value. But little progress was made in the improvement of this light or lamp until 1844, when Foucalt substituted pencils made of hard gas carbon for the charcoal pencils of Davy, and thereby, for the first time, produced a persistent, but short-lived, electric arc light. By a clock-work mechanism, Foucalt fed the pencils toward each other, but imperfectly regulated their burning. The voltaic battery did not generate electricity on a sufficiently large scale. The light was expensive, and it did not go into general use. Later, the dynamo electric machine was developed, in which a powerful current of electricity was produced by revolving coils of wire in a field of magnetic force furnished by powerful, permanent magnets, after which the arc electric light was successfully used in lighting houses in England, and later (1867) in France. But up to this time no means had been devised for producing an adequate current of electricity for illumination at practicable cost; and it was not until the invention of the Gramme dynamo electric machine, in 1872, that electricity was produced in a manner, and of sufficient strength, to render electric lighting practical and useful. This machine was afterwards improved in details of construction. In this state of the art, Brush entered the field of invention, and on May 7, 1878, obtained patent No. 203,412 for his arc lamp, which was superior to any lamp that had preceded it. This lamp, however, was not capable of burning continuously more than 8 or 10 hours, and, when used for all-night lighting, it was necessary to extinguish the light and renew the carbons; and, in order to obviate this defect, Brush invented the lamp in suit. His invention, and the means by which it is carried out, are thus described in the specification:

'My invention relates to electric lamps or light regulators; and it consists--First, in a lamp having two or more sets of carbons, adapted by any suitable means, to burn successively,-- that is, one set after another; second, in a lamp having two or more sets of carbons, each set adapted to move independently in burning and feeding; third, in a lamp having two or more sets of carbons, adapted each to have independent movements, and each operated and influenced by the same electric current; fourth, in a lamp having two or more sets of carbons, said carbons, by any suitable means being adapted to be separated dissimultaneously, whereby the voltaic arc between but a single set of carbons is produced; fifth, in the combination, with one of the carbons or carbon holders of a lamp employing two or more sets of carbons, as above mentioned, of a suitable collar, tube, or extended support, within or upon which the carbon or carbon holder to which it is applied shall rest, and be supported. * * * I desire to state, at the outstart, that my invention is not limited in its application to any specific form of lamp. It may be used in any form of voltaic arc light regulator, and would need but a mere modification in mechanical form to be adaptable to a indefinite variety of the present forms of electric lamps. My invention comprehends, broadly, any lamp or light regulator, where more than one set of carbons is employed, wherein--say in a lamp having two sets of carbons-- one set of carbons will separate before the other. For the purpose, merely, of showing and explaining the principle of operation and use of my invention, I shall describe it, in the form shown in the drawings, as applied to an electric lamp of the general type shown in United States letters patent No. 203,411, granted to me May 7, 1878, reissued May 20, 1879, and numbered 8,718. The leading feature of this type of regulator is that the carbon holder has a rod or tube which slides through or past a friction clutch, which clutch is operated upon to grasp and move said carbon rod or holder, and thus to separate the carbons and produce the voltaic arc light; and I shall refer to such a lamp in my following description: A represents one set of carbons; A1, another set, each carbon having an independent holder, B, B1. The carbon holders, B, B1, may either be in the form of a rod or tube, and each of them is made to pass through a clamping and lifting device, C, C1, respectively. These clamps and lifters, C, C1, are shown in the present instance in the shape of rings surrounding their respective carbon holders, B, B1. This form, while I have found it for general purposes the best, is not necessarily the only form of clamp that may be used in carrying out my present invention. Each ring clamp, C, C1, is adapted to be lifted from a single point, thus tilting it, and causing it to grasp and lift its inclosed carbon holder. This tilting and lifting movement is imparted to the clamps, C, C1, by any suitable lifter, D; and this lifter may have its movement imparted either by magnetic attraction, due to the current operating the lamp, or by the expansive action of heat upon any suitable apparatus connected with the lamp; said heat generated by the electric current operating the lamp. I do not in any degree limit myself to any specific method or mechanism for lifting, moving, or separating the carbon points, or their holders, so long as the peculiar functions and results hereinafter to be specified shall be accomplished. The lifter, D, in the present instance, is so formed that when it is raised it shall not operate upon the clamps, C, C1, simultaneously, but shall lift first one and then the other; preferably, the clamp, C, first, and C1, second, for reasons which will hereinafter appear. This function of dissimultaneous action upon the carbons or their holders, whereby one set of carbons shall be separated in advance of the other, constitutes the principal and most important feature of my present invention. In the lamp shown in the drawings the lifter, D, is actuated and controlled through the agency of magnetic attraction due to the influence of the current operating the lamp, and this is accomplished as follows: One, two, or more spools or hollow helices, E, of insulated wire, are placed in the circuit, within whose cavities freely move cores, E1. The electric current, passing through the helices, E, operate to strongly draw up within their cavities their respective cores, E1, in the same manner as specified in my former patent, above referred to. The cores, E1, are rigidly attached to a common bar, E2, and the upward and downward movement of this bar, due to the varying attraction of the helices, E, is imparted by a suitable link and lever connection, E3, E4, to the lifter, D. By this connection the lifter will have an up and down movement, in exact concert with the cores, E1; and it is apparent that this connection between magnet and lifter may be indefinitely varied without any departure from my invention, and therefore, while preferring for many purposes the construction just specified, I do not propose to limit myself to its use. The lifter, D, may be so constructed and applied as to separate the carbons, A and A1, successively or dissimultaneously, by being so balanced that any difference, however slight, between the weights of the carbons, A, A1, or their holders, B, B1, shall result in one being lifted and separated from the other. In order properly to balance the attractive force of the magnets, a coil spring, F, or its equivalent, may be employed, substantially as shown; and, to insure a stead motion to the magnets and to the carbon points, A, A1, a dash-pot, G, or its equivalent, should be employed, as this prevents any too sudden, abrupt, or excessive movement of parts. H, H1, are metallic cables, through which the current is conducted from above the clamps, C, C1, to the carbons, A, A1. By this provision is not only insured a good connection between the upper carbon points and the mechanism above it, but another important advantage is obtained, and that is the prevention of sparks due to any interruption of the current between...