Thomson-Houston Electric Co. v. McLean

153 F. 883, 82 C.C.A. 629, 1907 U.S. App. LEXIS 4475
CourtCourt of Appeals for the First Circuit
DecidedApril 11, 1907
DocketNo. 668
StatusPublished

This text of 153 F. 883 (Thomson-Houston Electric Co. v. McLean) is published on Counsel Stack Legal Research, covering Court of Appeals for the First Circuit 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. McLean, 153 F. 883, 82 C.C.A. 629, 1907 U.S. App. LEXIS 4475 (1st Cir. 1907).

Opinion

PUTNAM, Circuit Judge.

This is a bill in equity alleging infringement of letters patent No. 448,894, issued on March 24, .1891, to Elihu Thomson on an application filed on September 26, 1890. The patent contains 18 claims, but the bill alleges specifically infringements of only claims 12, 13, 14, and 17. Claims 15 and 16 have relation to the interpretation and effect to be given to those on which the bill is specifically rested, and therefore we will recite herein claims 12 to 17, each inclusive. The only issue before us arises on a plea alleging that the invention sued on had been previously patented in Great Britain by letters issued on December 23, 1890, as of July 8, 1890, so that, under the laws of Great Britain, the patent expired on July 8, 1904, and so that, consequently, the patent in suit, by force of section 4887 ■of the Revised Statutes [U. S. Comp. St. 1901, p. 3382], expired also on the day last named, and thus before the bill was filed. The plea was joined by a replication, thus bringing before the court issues of both fact and law. The Circuit Court rendered a judgment for the respondent, and the complainant appealed to us.

The introduction to the patent in suit describes it as consisting “in certain details of construction and combinations” concerning electric meters for use on either continuous or alternating current circuits, “more particularly applicable to meters wherein an electric motor is •employed, and the consumption is indicated or registered by the speed of such motor.” The specification also states that the meter as to which the patentee has shown the improvements covered by the patent .in suit is like that described-in an application filed on August 26, 1889, which resulted, as we understand, in the patent for the well-known Thomson meter of the motor type. Having especial reference to this, the counsel for the complainant says:

“The issues, then, have' to do with meters that record electrical energy; that is, they take account of the amount of current (the unit being called an ampere), and the pressure at which it is flowing (the unit of this being a volt). And the electrical circuits are so arranged that the rotating part, which is termed the ‘armature,’ revolves at a rate proportional to the product of the amount of current by the pressure. This product is electrical energy, whose unit is called the watt. As either the amount of the pressure or the current varies, the speed of rotation varies; and, as the counting train which actuates the dials is driven by the armature shaft or spindle, the dials record and [885]*885add or sum up, or integrate, the energy, or watts, flowing through the circuit, taking account of all variations. Such a device is called an ‘integrating,1, or “recording,’ watt meter.
“It will be made to appear that Prof. Thomson devised two general types of meter of this sort; one having a rotating, and the other an oscillating armature. The patent in suit contemplates certain improvements upon the rotating form.”

The complainant, also, explains that the patent in suit covers other improvements in the construction of meters, with which the claims involved here have nothing to do. These are quite fully explained in the specification, in part as follows:

“W is an artificial resistance in the circuit of the armature, but external thereto, and made high in amount, so as to limit the current and avoid the ne-1. cessity for winding the armature of extremely fine wire to stand considerable potential. By making this resistance very high in proportion to the armature-resistance, a praetically-coustant current in such armature under conditions of change of speed is attained, owing to the fact that the variations of resistance and counter electro-motive force in the armature itself will be so small in proportion to the total resistance as to be practically negligible. The high resistance, W, will therefore also have an important function practically abolishing any variations in the action of the motor arising from any change of resistance at the commutator-contacts, and will for this and the reason above noted add greatly to the regularity of action of the motor.”

The important claims are as follows:

“(12) In an electric meter, the combination, with an electric motor and a register for counting the movements thereof, of an artificial resistance external to the motor and placed in the circuit of such motor wherein a constant current is to be maintained; such resistance being the larger part of the total resistance of such motor-circuit.
“(13) The combination, with an electric meter operated by alternating currents, of a noninductive artificial resistance placed in that portion of the me-er-circuits wherein a constant current is maintained and made to form the larger part of the resistance of said circuit.
“(14) The combination, with an electric motor operated by alternating currents, of a register for counting the movements - of said motor, and a noninductive artificial resistance external to the motor and placed in the meter-circuit including the armature and commutator; such artificial resistance being made large in proportion to the resistance of the normal resistance of the armature and commutator.
“(15) The combination, in an electric meter, of an electric motor having its field traversed by current varying with the consumption and an armature for such motor placed in a constant-current circuit, in combination with an artificial resistance placed in the armature-circuit external thereto.
“(10) The combination, substantially as described, of an electric-motor field-coil, an electric-motor armature-coil provided with a commutator and placed in an alternating current circuit, including a noninductive resistance external to the armature and commutator, as and for the purpose described.
"(17) In an electric meter for measuring alternating electric currents, the combination, with that part of the motor which is included in a constant alternating-current circuit, of a noninductive resistance external to such part of the motor and made large in amount in proportion thereto.”

As the complainant makes much of the fact that the external resistance covered by the claims on which the bill is rested is, as said in claim IS, “the larger part of the total resistance of such motor-circuit,” we deem it important to call attention to the fact that claims 15 and 16 demand only an external resistance, without any condition as to its proportionate relation to the total resistance of the circuit to which the external resistance is incident. The complainant explains [886]*886this on the ground that they were evidently drawn “to anticipate an attempted evasion of the patent by making the external resistance somewhat less than that of the armature.”

The complainant urges on us' that whether the patent in suit expired as an entirety with the British patent cannot be determined, except bjr making a comparison claim by claim; so that, as it maintains, the mere fact that only one or more of the claims in the British patent were coequal with only one or more of the claims in the domestic patent would not affect the claims in the domestic patent not thus coequal, but would leave them still to run out the expressed term of the patent as granted. The complainant does not bring to our attention any controlling authority on this proposition. The nearest approximate is Siemens v.

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Siemens's Administrator v. Sellers
123 U.S. 276 (Supreme Court, 1887)
Thomson-Houston Electric Co. v. Ohio Brass Co.
80 F. 712 (Sixth Circuit, 1897)

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Bluebook (online)
153 F. 883, 82 C.C.A. 629, 1907 U.S. App. LEXIS 4475, Counsel Stack Legal Research, https://law.counselstack.com/opinion/thomson-houston-electric-co-v-mclean-ca1-1907.