Brush v. Condit

• Decision Date: 04 November 1889
• Citation: 132 U.S. 39,10 S.Ct. 1,33 L.Ed. 251
• Parties: BRUSH et al. v. CONDIT et al. 1
• Court: U.S. Supreme Court

132 U.S. 39

10 S.Ct. 1

33 L.Ed. 251

BRUSH et al. v. CONDIT et al.¹

November 4, 1889.

W. C. Witter and Wm. H. Kenyon, for appellants.

Edmund Wetmore and Samuel A. Duncan, for appellees.

BLATCHFORD, J.

This is an appeal by the plaintiffs, Charles F. Brush and the Brush Electric Company, in a suit in equity brought by them in the circuit court of the United States for the southern district of New York, against C. Harrison Condit, Joseph Hanson, and Abraham Van Winkle, from a decree dismissing, with costs, their bill of complaint, so far as it relates to reissued letters patent No. 8,718, granted May 20, 1879, to Charles F. Brush, one of the plaintiffs, for 'improvements in electric lamps,' on an application for a reissue filed April 14, 1879, the original letters patent, No. 203,411, having been granted to said Brush, May 7, 1878, on an application filed September 28, 1877. The rights of the plaintiffs were finally rested upon an alleged infringement of claims 1, 3, 5, and 6 of the reissue. Another patent was sued on in the case, but at the final hearing the bill in regard to it was dismissed with costs, on motion of the plaintiffs. The opinion of the circuit court, held by Judge SHIPMAN on the merits, as to reissue No. 8,718, is reported in 22 Blatchf. 246, 20 Fed. Rep. 826.

The specification of the reissue states the general nature of the invention in these words: 'My invention relates to electric light mechanism, and it consists in the following specified device, or its equivalent, whereby the carbon sticks usually employed are automatically adjusted and kept in such position and relation to each other that a continous and effective light shall be had without the necessity of any manual interference.' In this automatic arrangement the electric arc is established, and then, as the electrodes are consumed the are is regulated by causing the strength of the current and the length of the are mutually to control each other. There is no clock-work or other extraneous power, but the action of the electric current alone effects the necessary movements. The electrodes tend to move towards each other at all times, and this tendency is opposed by the electro-magnetic action, which tends to separate them. These opposing forces are designed to be in equilibrium when the electrodes are at such a distance from each other as will produce the maximum development of light with a given electric current. It was to an electric arc lamp of this character that the invention of Brush was to be applied. The construction of his arrangement, as described in the specification of the reissue, is as follows: A helix of insulated wire, such helix being in the form of a tube or hollow cylinder, rests upon an insulated plate upheld by a metallic post or standard. Within the cavity of the helix are contained an iron core and a rod which passes longitudinally and loosely through and within the core. This rod holds a carbon. The core is also made to move very freely within the cavity of the helix, and is partially supported by means of springs which push upward against ears attached to the core. A ring of metal just below the core surrounds the carbon holder, and rests upon a floor or support. One edge of the ring is over a lifting tongue, which is attached to the core, while the opposite edge is a short distance below the crown of an adjustable set-screw. The design is that one point of the ring may be lifted in such way as to clamp the carbon holder, while a limit is placed to the upward movement of the core. The poles of the battery being so attached that the circuit of an electric current is completed, the core, by the force of the axial magnetism, is drawn up within the cavity of the helix, and by means of the lifting tongue one edge of the ring is lifted until, by its angular impingement against the rod or carbon holder, it clamps such rod, and also lifts it up to a distance limited by an adjustable stop. While the ring preserves this angular relation with and impingement against the rod, the rod will be firmly retained, and prevented from moving through the ring. The adjustable stop is fixed so that it shall arrest the lifting of the rod when the two carbons are sufficiently separated from each other. While the electric current is not passing, the rod can slide readily through the loose ring and the core; and, in this condition, gravity will cause the upper carbon to rest upon the lower carbon, thus bringing the various parts of the device into the position of a closed circuit. If, then, a current of electricity is passed through the apparatus, it will instantly operate to lift the rod, and thus separate the two carbons, and produce the electric light. As the carbons burn away, thus increasing the length of the voltaic arc, the electric current diminishes in strength, owing to the increased resistance. This weakens the magnetism of the helix, and accordingly the core, rod, and upper carbon move downward, by the force of gravity, until the consequent shortening of the voltaic are increases the strength of the current, and stops such downward movement. After a time, however, the ring will reach its floor or support, and its downward movement will be arrested. Any further downward movement of the core, however slight, will at once release the rod, allowing it to slide through the ring until arrested by the upward movement of the core, due to the increased magnetism. In continued operation, the normal position of the ring is in contact with its lower support, the office of the core being to regulate the sliding of the rod through it. If, however, the rod accidentally slides too far, it will instantly and automatically be raised again as at first, and the carbon points thus be continued in proper relation to each other. Claims 1, 3, 5, and 6 of the reissue, on which alone recovery is sought, read as follows, there being eight claims in all in the reissue as granted: '(1) In an electric lamp, the combination, with the carbon holder and core, of a clamp surrounding the carbon holder, said clamp being independent of the core, but adapted to be raised by a lifter secured thereto, substantially as set forth.' '(3) In an electric lamp, the combination of the core or armature, C, the clamp, D, and adjustable stop, D¹, or their equivaents, whereby the points of the carbons are separated from each other when an electrical current is established,—prevented from separating so as to break the current,—and gradually fed together as the carbons are consumed, substantially as described.' '(5) In an electric lamp, the combination, with a carbon holder, of an annular clamp surrounding the carbon holder, said clamp adapted to be moved, and thereby to separate the carbon points by electrical or magnetic action, substantially as herein set forth. (6) In an electric lamp, an annular clamp adapted to grasp and move a carbon holder, substantially as shown.' What is called in these claims 'the clamp, D,' is the ring of meta which surrounds the rod or carbon holder. The specification of the reissue, as granted, contained the following paragraph: 'I do not limit myself narrowly to the ring, D, as other devices may be employed which would accomplish the same result. Any device may be used which, while a current of electricity is not passing through the helix, A, will permit the rod, B, to move freely up and down, but which, when a current of electricity is passing through the helix, will, by the raising of the core, C, operate both to clamp and to raise the rod, B, and thereby separate the carbon points, F, F', and retain them in proper relation to each other.'

On the 14th of October, 1881, the plaintiffs filed in the patent-office a disclaimer, in which they stated that the patentee had claimed more than that of which he was the first inventor or discoverer, by or in consequence of the use, in the specification, of the language contained in the paragraph last above quoted; and that there were material and substantial parts of the thing patented, also embraced within the terms of the above quoted paragraph, which were truly and justly the invention of Brush. The paper went on to enter a disclaimer to that part of the subject-matter of the specification, and of claims 1, 2, 3, 5, and 6 of the reissue, which, being embraced within the general language of the above quoted paragraph, included as within the invention of Brush 'clamping devices substantially different in construction and mode of operation from the clamp, D.' On the 6th of April, 1883, the...