Safety Car Heating & Lighting Co. v. United States Light & Heating Co.

• Decision Date: 11 December 1914
• Docket Number: A-2.
• Citation: 222 F. 310
• Parties: SAFETY CAR HEATING & LIGHTING CO. v. UNITED STATES LIGHT & HEATING CO.
• Court: U.S. District Court — Western District of New York

222 F. 310

SAFETY CAR HEATING & LIGHTING CO. v. UNITED STATES LIGHT & HEATING CO.

No. A-2.

United States District Court, W.D. New York.

December 11, 1914

Duell Warfield & Duell, of New York City (C. H. Duell, F. P Warfield, H. S. Duell, R. S. Blair, and D. G. Haynes, all of New York City, of counsel), for complainant.

Jones Addington, Ames & Seibold, of Chicago, Ill., and Kenefick Cooke, Mitchell & Bass, of Buffalo, N.Y. (W. Clyde Jones, Arthur B. Seibold, and Edwin B. H. Tower, Jr., all of Chicago, Ill., of counsel), for defendant.

HAZEL District Judge.

The bill in this case alleges infringement of letters patent No. 747,686, granted to John L. Creveling, December 22, 1903, for a system of electrical regulation adapted for use in supplying current to the lamps of railroad cars. There are 11 claims in the patent, but 8 only are alleged to be infringed by the lighting system of the defendant company. This court recently had before it for determination in another case between the complainant and defendant herein, argued and submitted just before this case was submitted for decision, the asserted infringement of the Thomson patent which it was claimed was an improvement on the Creveling patent in suit, and the opinion in that case is filed simultaneously with this. 222 F. 318.

We are herein principally concerned, first, with the combination of means whereby the current output of the generator, which is belted to the car axle and which runs at rates varying with the speed of the train, is maintained at substantially constant voltage, thus producing steady and continuous car lighting; and, second, with the combination for protecting the storage battery from overflow or exhaustion-- the means affording such protection being an automatic device which opposes the generator voltage and modifies or alters the flow of the generator current by increasing or decreasing it at variable stages or periods.

The specification of the patent under discussion, supported by the explanations of the expert witnesses, clearly indicates that in the described system of electrical regulation the total current output of the generator is steady and continuous while the train runs at a rate of 15 miles or more an hour; that the lamps are in parallel and the current controlled by a main field coil 8 in the main circuit, forming part of the field winding of pilot motor 7, while the other part of the field winding of the motor is coil 9, thinner than the main field coil, which opposes the latter and causes the fields to operate so as to neutralize one another. The pilot motor is not in the magnetic field and therefore does not operate, and any slight armature current there may be is without operative effect; but the function of coil 9 is to receive the excess current flowing through coil 8, the field of which then preponderates, causing the armature to rotate in such direction that the worm 36 and wheel 37 swing the rheostat arm 20 to provide the additional resistance in the field circuit of the dynamo. By this arrangement of the parts there is produced a weakening of the field circuits of the dynamo which then operate to restore the current to a normal flow. When there is a decreased current in the generator field there is a stronger flow in coil 9 which causes the actuating means of the rheostat arm-- that is, the worm and wheel-- to rotate in an opposite direction, decreasing the resistance of the field circuit of the dynamo and securing a normal current. The changes of the voltage are frequent, and, owing to the worm and wheel connection, the movements of the rheostat arm are also frequent, corresponding thereto to maintain a practically constant generator output until the battery is sufficiently charged, and this, regardless of the varying speed of the generator or variations in resistance of the main circuit. It will be understood, I take it, from what has been said, that variance in the current flow due to variation in the speed of the train or to the turning on or off of the lights is equalized by the adaptation of the means hereinbefore described, and that when the lamps are lighted the total current from the dynamo is divided between the lamps and the storage battery; the former taking only the amount required by them for lighting, and the latter the balance for subsequent utilization.

The mechanism by which the storage battery or accumulator is protected comprises a solenoid device (31) connected across the principal wires of the generator and on the side of the line switch (6). When the battery is charged to nearly its full capacity the voltage increases, so as to enable the solenoid to influence the contact arm (34) and bring into operation a resistance (15) and hence a lowering of the electromotive force in the field coil (9) below the force of the current which flows through the main coil and causes the pilot motor to rotate in a direction to effect another resistance in the main circuit which reduces the generator output, again neutralizing the current of the field coils. The function of the automatic switch is manifestly to break the main circuit whenever the generator voltage is low, although there may be a discontinuance of the current to the battery while the switch is closed, this occurring whenever the flow is greatly diminished, as, for instance, by the stopping of the train or by its slowing down below 15 miles an hour. In further explanation of the function of the protection device when the train starts up after coming to a full stop, the complainant's brief accurately says: 'As coil 31 is on the side of the automatic switch away from the battery, it can get current from the battery only when this switch is closed. As the train again speeds up or starts up, the automatic switch 6 is closed, and the original cycle of operations completed, except only in the case in which the battery is still fully charged; that is, at about its full-charged voltage. If such is the case, the coil 31 immediately performs its functions to cut down or cut off the charging current. If, however, the battery is not at or near this full-charged voltage, the practically constant generator output, at its normal value, is maintained as usual.'

The principal advantages claimed to attach to the patent in suit are that the normal relation of battery and generator is at all times maintained and that any depletion of current in the battery by reason of lamp load or from stoppage of the train is instantly made good, thus securing continuous and steady lighting for the cars.

A diagrammatic sketch (Fig. II) attached to the specification is herewith reproduced.

(Image Omitted)

Claim 5, which is typical of the other claims, reads as follows:

'5. In a system of electrical distribution, the combination of a generator, and accumulator charged thereby, means for maintaining the current output of the generator practically constant throughout changes in speed, and automatic means, controlled by voltage of the accumulator, for altering the current upon changes in voltage of said accumulator.'

The claims do not in terms refer to a railroad car lighting system; but the specification describing the generator and its purposes, and the adaptation for charging the battery to maintain the current output constant, leaves no doubt in the mind that the claims are in fact limited to an electric car lighting system. The prior art, thus limited, is subject to scrutiny.

The defendant insists that, long before the invention in suit was conceived, generator regulators were used commercially, first separately, and later in connection with a protection device to prevent...