Union Switch & Signal Co. v. Hall Switch & Signal Co.

228 F. 709, 1915 U.S. Dist. LEXIS 1014
CourtDistrict Court, D. Maine
DecidedDecember 14, 1915
DocketNo. 726
StatusPublished
Cited by2 cases

This text of 228 F. 709 (Union Switch & Signal Co. v. Hall Switch & Signal Co.) is published on Counsel Stack Legal Research, covering District Court, D. Maine primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Union Switch & Signal Co. v. Hall Switch & Signal Co., 228 F. 709, 1915 U.S. Dist. LEXIS 1014 (D. Me. 1915).

Opinion

HALE, District Judge.

This is a suit to enjoin the infringement of United States letters patent 819,322, issued May 1, 1906, to Jacob B. Struble, for improvements in electric signaling. At the opening of the specification, the character of the invention is stated as follows:

The invention described herein relates to certain improvements In automatic electric signals for electric railways, and has for its object the overcoming the danger of a signal being operated by reason of leakage of the current employed in operating the cars or other foreign current and the improper energizing of the slgnal-control'llng mechanism by such wild currents.
In general terms the invention consists in tho employment of an alternating current in the track circuits for energizing the translating device or relay controlling the signal circuit, which is controlled by neutral and polarized armatures of the track relay or relays.

The. complainant alleges infringement of claims 4, 11, 12, 13, and 15, namely:

4. In a signaling system, the combination of a closed track circuit, an alternating current supply therefor, a signal, and means to control the operation of said signal, said means responding to the absence or presence of the alternating current in the track circuit and not responding to continuous or direct currents traversing said track circuit in its control of the signal.
11. In a signaling system for use on railways employing an electric current as a motive power and the track as a return for the electric current, the combination of a circuit which includes portions of both rails, an alternating current supply for such circuit, and a translating device responsive to the presence or absence in it of the alternating current in said track circuit to control a signal and not responsive to the motive power current or continuous or direct currents in said circuit in its control of a signal.
12. In a signaling system for use on railways employing a direct current as a motive power and the track as a return for the direct current, the combination of a circuit which includes portions of both rails, an alternating current supply for such circuit, and a translating device responding to the presence or absence in it of alternating current in said circuit in its control of, a [710]*710signal and not responding to continuous or direct currents in said circuit in its control of a signal.
13. In a signaling system the combination of a track circuit, a constant source of alternating current supply therefor, a signal, and means to control the operation of said signal, said means responding to the absence or presence of the alternating current in the track circuit and not responding to continuous or direct currents traversing said track circuit in its control of the signal.
15. In a signaling system the combination of a closed track circuit, a constant source of alternating current supply therefor, a signal and means to control the operation of said signal, said means responding to the absence or presence of the alternating current in the track circuit, and not responding to continuous or direct currents traversing said track circuit when the signal is at “danger.”

The complainant contends that, in these claims, S'truble presents a generic invention; that he was the first to provide a system of electric block signaling suitable for use on electric railroads, a system in which interference between the signaling circuit and the power circuit was prevented, and that he did this by using a signal current different from the propulsion current; that he used a direct current for operating the car motors, and an alternating current for providing energy to the signal relays; that nothing in the prior.art discloses such invention; and that hence the claims at issue show Struble to be the pioneer in this field. The defendant denies infringement, and says that these claims are invalid in view of the prior patented art, and because they are not pertinent to anything disclosed in the drawings and specification of the patent in suit; that they are invalid, also, because the system disclosed by them is inherently useless and inoperative.

1.Anticipation. The claims at issue present a combination of five elements, to wit:

1. A railway track divided into blocks.
2. A closed track circuit.
3. An alternating current supply therefor.
4. A signal.
5. Means responding to the absence or presence of the alternating current on the track circuit and not responding to continuous or direct currents traversing said track circuit in its control of the signal.

The defendant says that this combination is found broadly in prior patents, and was well known in the art. It therefore becomes necessary to consider first what is disclosed in the prior patented art. In March, 1875, Henry W. Spang, of Reading, Pa., applied for his patent, No. 168,059. At the outset of his specification, he says:

My invention relates to that class of electrical railway signaling apparatus, audible or visual, or both combined, which is operated in connection with the rails of an insulated section or sections of railway track, and in which the electric circuit or circuits which control the signaling apparatus can only be properly brought into action, and a safety signal given, when the opposite rails of the said insulated section or sections of track are not occupied or metallically connected, as by the wheels and axles of a locomotive or car.
It consists, first, in certain novel combinations and arrangements of the rails of an insulated section or sections of railway, one or more galvanic batteries or other, sources of electricity, conductors, devices for changing, closing, and breaking circuit, and one or more signaling apparatus, audible or visual, or both combined, in which the safety signal is indicated by a series of movements of signal, or series -of bell taps, or other series of signs or sounds, or [711]

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Bluebook (online)
228 F. 709, 1915 U.S. Dist. LEXIS 1014, Counsel Stack Legal Research, https://law.counselstack.com/opinion/union-switch-signal-co-v-hall-switch-signal-co-med-1915.