Dominion Magnesium Limited v. The United States

320 F.2d 388
CourtUnited States Court of Claims
DecidedOctober 11, 1963
Docket667-53
StatusPublished
Cited by1 cases

This text of 320 F.2d 388 (Dominion Magnesium Limited v. The United States) is published on Counsel Stack Legal Research, covering United States Court of Claims primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Dominion Magnesium Limited v. The United States, 320 F.2d 388 (cc 1963).

Opinions

DAVIS, Judge.1

This is a patent suit under 28 U.S.C. § 1498, in which recovery is sought for reasonable and entire compensation for the unlicensed use by or for the Government of patented inventions. Plaintiff, a corporation of Ontario, Canada, is the record owner of United States Letters Patent Nos. 2,330,142 and 2,330,143 (referred to as the ’142 and ’143 patents), naming Lloyd Montgomery Pidgeon as inventor, and issued to plaintiff on September 21, 1943. These patents relate to methods and apparatus for obtaining magnesium, and, in the case of ’142, other volatizable metals.2 Plaintiff contends that one claim of the ’142 patent and three claims of the ’143 patent have been infringed by defendant’s use of magnesium-producing plants located at Canaan, Connecticut; Wingdale, New York; and Manteca, California.3 Defendant’s position is that the patents are invalid and have not been infringed. We have concluded that the patents, properly construed, were not infringed by the defendant’s operation of the accused magnesium-producing plants. Since that result disposes of the question of liability, we need not consider the numerous arguments advanced by the parties pertaining to the validity of the patents.

[390]*390Late in 1941, efforts were made to increase the production of magnesium metal previously obtained in commercial quantities by electrolytic processes. In November 1941, representatives of defendant’s Bureau of Mines and Office of Production Management visited Dr. Lloyd M. Pidgeon in Ottawa and inspected his pilot plant operations utilizing retorts for producing magnesium by thermal processes. Subsequently, plaintiff’s consulting engineers were released by plaintiff to defendant to aid in the Government’s construction and operation of magnesium-producing plants at Canaan, Wingdale, and other locations in the United States. Upon the grant of its ’142 and ’143 patents in 1943, plaintiff asserted a claim against defendant. A settlement of this 1943 claim was reached in 1949 under which plaintiff received $125,000 from the defendant for all designs, plans, drawings, constructions, operating and maintenance instructions, engineering data, details, services, trade secrets, inventions or technical information, etc., furnished by plaintiff to the United States and relating to the production of magnesium by the ferrosilicon retort process. The settlement agreement specifically provided that it was not to be construed as a license for continuing operation under any patent owned by plaintiff. The present suit is directed against defendant’s operation of its magnesium plants since the 1949 agreement and more particularly for operations during the period of the Korean hostilities. Patents ’142 and ’143 expired in 1960.

The patents relate to apparatus and methods for volatilizing and condensing magnesium under low pressure and high heat in metal retorts. Each patent refers to a thermal reduction operation for producing metal vapors which are then condensed in a cooled portion of the apparatus. A fuller description of the apparatus and methods disclosed and claimed in the ’142 and ’143 patents is given in the findings. Briefly stated, the method in general includes placing a charge of magnesium-containing material in the heated zone of a tubular metal retort within a furnace, closing and evacuating the retort, condensing magnesium m a removable condenser sleeve positioned in a cooled zone of the retort outside of the furnace, opening the retort for removing the sleeve containing condensed magnesium, and repeating the cycle. Both patents describe the use of a fractionating means or condenser within the removable condensing sleeve, consisting of a series of spaced metal discs or plates which provide a circuitous or relatively long path of travel for vapors. This fractionating condenser is designed to condense metals of relatively high vapor pressure, such as sodium, separately from the magnesium, and to provide a means of removing those metals independently of the magnesium. By achieving a substantial separation of the magnesium condensate from the condensates of more volatile metals, the fractionating condenser not only makes possible the production of high-purity magnesium, but also reduces the likelihood of ignition of the magnesium, caused by burning of more readily combustible sodium and pyrophoric magnesium during discharge of the condenser.

With reference to the fractionating condenser, the specification of the ’143 patent states that the innermost disk — ■ the disk closest to the hot, or reduction, end of the retort — is “out of thermal contact with the condenser wall and remains at a higher temperature than the other disks.” This innermost disk of the condenser, sometimes referred to by counsel as the “vital plate,” serves to deflect to the wall of the removable condenser sleeve the magnesium vapors impinging thereon. The specification also states that this disk, “being out of direct thermal contact with the condenser wall and remaining hot, insures deposition of the magnesium only on the wall of the removable condenser, where it builds up into a unitary structure with an inwardly projecting ledge.” The ’142 specification, in describing the series of spaced plates used in the apparatus, states that the innermost of the plates is of a lesser diameter than the retort, and “is substantially independent of the cooler and [391]*391in operation does not accumulate condensate.”

In the normal operation of the apparatus illustrated in the ’142 and ’143 patents, magnesium does not condense on this vital plate. The magnesium vapor deflects off the hot vital plate and condenses on the wall of the condenser sleeve between the vital plate and the furnace end of the sleeve. The sodium vapor, which has a higher vapor pressure than magnesium and requires a colder surface for condensing, passes around the edge of the vital plate and condenses beyond the magnesium condensing zone. When the evolution of vapors from the material with which the furnace is charged is completed and the vapors have been condensed, the vacuum is broken and the retort and condenser sleeve are opened. The fractionating condenser is then removed, carrying with it any pyrophoric metal fraction which most readily ignites when hot upon exposure to air, and which, if not removed, would be likely to ignite the hot magnesium in the condenser sleeve. The removable sleeve, containing the pure magnesium fraction, is then removed without the necessity of further cooling to avoid ignition. After removing the residue of the charge from the retort, the retort is ready for a new charge, new condenser sleeve, and replacement of the fractionating condenser and closure members. The method of operation taught by the patents makes it possible to repeat the cycle without successively heating and cooling down the retort, thus prolonging its useful life and avoiding heat loss.

One prime question is the state of the prior art in this field. Numerous patents and publications relating to apparatus and methods for the production of magnesium by thermal action were available prior'to November 3, 1941, and February 11, 1942, the respective filing dates of the ’142 and ’143 patent'applications.

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Related

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3 Cl. Ct. 161 (Court of Claims, 1983)

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Bluebook (online)
320 F.2d 388, Counsel Stack Legal Research, https://law.counselstack.com/opinion/dominion-magnesium-limited-v-the-united-states-cc-1963.