General Electric Co. v. Sundh Electric Co.

221 F. 657, 1915 U.S. Dist. LEXIS 1610
CourtDistrict Court, S.D. New York
DecidedMarch 16, 1915
StatusPublished

This text of 221 F. 657 (General Electric Co. v. Sundh Electric Co.) is published on Counsel Stack Legal Research, covering District Court, S.D. New York primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
General Electric Co. v. Sundh Electric Co., 221 F. 657, 1915 U.S. Dist. LEXIS 1610 (S.D.N.Y. 1915).

Opinion

MAYER, District Judge.

Claims 27 and 28 have been withdrawn, and therefore the claims in issue are Nos. 1, 2, 3, and 4, and these are as follows:

“1. In combination, a plurality of separately actuated contacts operatively related to a circuit to be controlled, means for operating said contacts, and means for securing a certain time interval between the operation of the successive contacts without interfering with the free operation of the individual contacts.
‘•2. A motor-controller of the separately actuated contact type, comprising speed-controlling contacts, means for operating said contacts, and time-limiting devices constructed and arranged to control the successive operation of said contacts without interfering with the free operation of the individual contacts.
“3. A motor-controller of the separately actuated contact type, comprising speed-eon trolling contacts, means for closing said contacts in succession, and Lime-limiting devices constructed and arranged to regulate the successive closing of said contacts without interfering with the free operation of the individual contacts. ,
•‘4. A motor-controller, comprising a series of separately actuated contacts, an actuating system therefor, means whereby the operation of each of certain [658]*658contacts is controlled by a preceding contact in the series, and means for securing definite time intervals between the operation of the contacts without interfering with the free operation of the individual contacts.”

The invention of the patent in suit relates to “controllers” in the electrical art, which cut out artificial resistance external to the motor, so as to control the motor, particularly at starting. The earliest controllers were manually operated, but these were improved upon by what are known as the separately actuated contact type, to which the invention in suit is addressed. In this latter type there is a series of separate switches, each controlling one section of resistance and having its contacts operated by its own individual magnet. If the resistances are in series, each magnet cuts out a section of resistance, so as to diminish the total amount, or, if the resistances are in multiple, as in the Linn patent, then it connects its section of resistance in circuit, so as to increase the number of paths which the current may follow, thereby diminishing the resistance.

In order to provide for the consecutive action of these resistance switches, each magnet not only closes its own resistance switch, but also closes the actuating circuit of the next succeeding magnet, so that, after the operator has moved the master switch so as to close the circuit of the first magnet, the other magnets follow automatically. It was important, and indeed necessary, to determine in some manner or by some method the speed with which this series of magnets would be operated; for, if the resistances were thrown out too rapidly, too great a starting current would flow in the motor, with the possibility of grave damage. On the other hand, if the resistances were cut out too slowly, the motor would be accelerated too slowly, and such a result might be serious, especially in elevators and electric railways.

Various methods have been devised to control the rate of operation of the switches. A well-known and apparently much-used type is the so-called “throttle” magnet. There the throttle magnet was placed in the motor circuit, which responded to the amount of current in the circuit, and whenever that current exceeded a safe limit the throttle magnet suspended the progressive action of the successively acting resistance magnets. (See Fraser patent, No. 655,335.)

In another type of controller, illustrated by the Cutler patent, No. 653,470, the resistance magnets were so connected with the terminals of the motor armature as to be responsive to the increasing counter electromotive force of the motor, each magnet operating at a certain point in the building up of the counter electromotive force; hence the magnets Would successively act to diminish resistance, as the counter electromotive force increased and the current consequently became less.

The rate of progress in both these types of controller varied with the electrical conditions. In many cases, however, it is possible to determine beforehand the rate of progress at which it is desired that the switches should act, since the motor conditions will not vary materially. In ' such a type of controller the resistances should be removed in succession, with a definite period of time between the operation of the succeeding resistance switches.

[659]*659The advantage of this type of controller is that it makes a simple form, free from complications, and has the qualities,_ as stated by the expert Bentley, of “a clean, positive, and strong action of the resistance switch at a perfectly definite time, which can be readily and certainly set to suit the particular requirements of the individual installation.” It is such a “time limit controller” which is the subject of the claims of the Linn patent in controversy, and which it is asserted has been made and sold by defendant in infringement of Linn’s patent.

The issues in the case are clean-cut and are unusually free from side complications or questions. The important and fundamental point to be determined is whether the Linn patent has been anticipated, or is invalid for want of invention in view of the prior art.

While the electrical art has many difficulties for the layman, and has developed a language of its own, yet the controversy here does not suggest difficulty, once the question is grasped and the terms of art are understood. I shall not set forth definitions, nor the various accepted laws relating to the flow and action of the electrical current, for I am assuming that this opinion is for the information of litigants and counsel versed in the subject-matter.

What Linn accomplished was to obtain a desired result by mechanical means, and in this respect he originated an entirely new conception. The mechanism itself was not novel, but Linn’s thought was that tlie time interval between the closing of the contacts of one magnet to govern its section of resistance and the closing of the similar speed-controlling contacts of the next magnet should be governed by freely and quickly operating each magnet to close its speed-controlling contacts as soon as its actuating circuit is* dosed, and then providing by mechanical means a definite lime interval between the closure of these contacts and the closure of tlie actuating circuit of the next magnet.

When the actuating circuit of a resistance magnet is closed, the magnet acts immediately to close its own main contacts, which cut out the resistance, but does not cause the closing of the actuating circuit of the next magnet until after a definite time limit; this delay being secured specifically by retarding through a dashpot arrangement of common type, the supplemental contacts which control the actuating circuit of the succeeding magnet. Linn’s purpose, and the broad problem with which he was dealing, are aptly set forth by him as follows:

“Tlie present Invention relates to a system of control employing a controller of the separately actuated contact type in which the several controller contacts are operated by means of circuit connections so arranged that the system will be automatic, or at least partially automatic, in its operation.

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Bluebook (online)
221 F. 657, 1915 U.S. Dist. LEXIS 1610, Counsel Stack Legal Research, https://law.counselstack.com/opinion/general-electric-co-v-sundh-electric-co-nysd-1915.