Thomson-Houston Electric Co. v. Lorain Steel Co.

103 F. 641, 1900 U.S. App. LEXIS 4678
CourtU.S. Circuit Court for the District of Southern New York
DecidedJuly 11, 1900
StatusPublished
Cited by2 cases

This text of 103 F. 641 (Thomson-Houston Electric Co. v. Lorain Steel Co.) is published on Counsel Stack Legal Research, covering U.S. Circuit Court for the District of Southern New York primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Thomson-Houston Electric Co. v. Lorain Steel Co., 103 F. 641, 1900 U.S. App. LEXIS 4678 (circtsdny 1900).

Opinion

SHIPMAN, Circuit Judge.

This bill in ment by the defendant of claims 1, 2, 8, and 4 of letters patent No. 428,109, dated May 20, 1890, issued to Walter H. Knight for an improved electric motor regulator. The patent has been owned by the complainant since November 7, 1891. The invention was adapted to electric railway motors working on a circuit of “constant potential,” and was designed to prevent the sudden overloading of the motor. The patentee says in his specification:

“In motors on a circuit of this character, it is essential that a resistance or other device for opposing the electro-motive force should be inserted in the circuit whenever the motor is at rest, or its counter-electro-motive force sub-, stantially diminished. Since a reversal of the motor, of course, reverses its counter-electro-motive force, it is essential that it should only be reversed when the motor is at rest; and when there is substantially no current passing through it. A sudden reversal of the motor when in operation so affects the counterelectro-motive force that, unless a resistance is inserted, the sudden flow of current which ensues is so great as to bum out the machine. Moreover, when the reversing device is a switch controlling the direction of current in either the field magnet or armature, it is apt to be injured by operating it while the current is passing.”

When the motor is suddenly reversed, and the counter-electromotive force is also reversed in consequence, if the motor cannot instantly get up speed in the opposite direction, it is in danger of being burned out; and, if the car is reversed very suddenly, pedestrians or carriages in the rear are in danger of accident. In the preexisting motors, a single handle was used, which was moved each way from a central position upon the regulator. A forward movement sent the car forward, a reverse movement to the central position stopped it, and it was reversed by a continuation beyond that point. The danger was that in a sudden, not anticipated "emergency, the motorman would lose his presence of mind, and send the [642]*642car whirling backward, or that he would move his handle too far and reverse when he merely wished to stop. Separate handles were also provided, but, unless a definite stop was interposed, both the difficulty of ascertaining the precise point when the movement of the handle was to be stayed, and the danger, continued.

The patentee described in his specification his invention, as follows:.

“My invention consists in providing a reversing mechanism for the motor, with a stop or lock, so that it can be operated only when there is a sufficient amount of resistance inserted to prevent injury, and it, furthermore, consists in providing a stop or lock for the resistance-controller or regulator of the machine, by which, when the reversing mechanism is at the neutral point, the resistance cannot be cut out. These devices absolutely prevent reversal of the motor at an improper time, and also the operation of the regulator, unless the reversing mechanism is set in one direction or the other.”

The locking device or “stop” is described as follows by the complainant’s expert:

“There is shown in Fig. 1 a reversing device, with the lever or handle, A, and a controlling or regulating device, with the handle or lever, G. The reverser is indicated as an oid-fashioned brush-shifter, but the inventor contemplates also the use of a reversing switch for changing the direction of current flow in the field magnet or armature, and so states in the specification, it being an immaterial matter what form the reversing device- may take. The controller is shown as an old rheostatic controller, such as was the standard at that date; it being remembered that the application'was filed March 13, 1886, a very early date in the practical development of electric railway apparatus. To the lever, A, is jointed a connecting-rod, E, which is in turn pivoted to a triangular-shaped block, F, having two projecting-pins, G, standing, when the 'le-Ver is in its central position, in a gap in a flange formed’ on a sector on the [643]*643lower side of the regulating- lever, C. Tlijis, when the reversing device is in its central position, the motor having no tendency either forward or backward, it is impossible to move the controller or regulator by reason of the flange, D, striking the pin, G. This is the condition shown in Fig. 1 of the patent. When, however, the reverser, A, is thrown to one side or the other, the block, F, is turned into the position shown in Fig. 2, or into the position shown in Fig. 3, according to whether the reverser is moved to the left or to the right; but in either case one of the pins, G, is tamed t.o the inside of the flange, I), and the other to the outside of the flange, so that the regulator can be turned, the flange passing between the two pins without interference. Conversely, when the regulating lever. C, has been turned as just mentioned, so as to interpose the flange, t>, between the two pins, G, it is impossible to move the reversing-lever, A, since the pins, G, by their engagement with the flange, 1), will not allow the block, F, to turn by a push or pull on the connecting-rod, M, and consequently the reversing lever is locked.”

It will thus he seen that the reversing and regulating devices act independently, but each device is used to lock the other, and the reversal of the motor cannot take place until the motorman unlocks it, and he cannot unlock it until he has brought the regulator to its “off” position; neither can he turn the current on and operate the regulator until the reverser is in its proper position. This stop locks one device or the other, and thus “compels the alternate operation of reverser and regulator by the operator,” but when either is in operation it is unaffected by the other. The invention is the combination of the other elements with a novel and positive stop, which compels the motorman to an observance of its check upon the movements of the handle of both regulator and reverser, and is described in the four claims which are in controversy as follows:

“(1) The combination, with an electric motor, of a reversing device and. regulator therefor, means for operating the same, and a stop for the reversing device, controlled by the regulator, whereby the reversing device can be operated only when the regulator is in a predetermined position. (2) The combination, with an electric motor, of a reversing device therefor, a. regulator, a stop for the reversing device, controlled by Hie regulator for locking the reversing device, so as to prevent its being operated, except when the regulator is substantially at the point of maximum control. (3) The combination, with an electric motor, of a regulator therefor, a stop or lock for the regulator, and a reversing device for the motor connected to said stop, whereby the said stop is operated by the reversing device to lock the regulator against movement, except when the reversing device Is in a predetermined position. (4) The combination, with an electric motor, on a constant-potential circuit, of a regulator and reversing device therefor, operated independently of one another, and an intermediate stop or lock connection, whereby the regulator and reversing device each controls the movement of the other.”

The defendant, in attempting the defense of lack of novelty in the invention of the patent in suit, presents letters patent for electric motors to Edward Weston, No. 264,982,' dated September 26, 1882; to Ernest W. Siemens, No.

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Related

Hildreth v. Mastoras
253 F. 68 (D. Oregon, 1918)
Thomson-Houston Electric Co. v. Garrett Coal Co.
144 F. 434 (U.S. Circuit Court for the District of Western Pennsylvania, 1906)

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Bluebook (online)
103 F. 641, 1900 U.S. App. LEXIS 4678, Counsel Stack Legal Research, https://law.counselstack.com/opinion/thomson-houston-electric-co-v-lorain-steel-co-circtsdny-1900.