Fyr-fyter Company, Appellant, v. International Chemical Extinguisher Corp., Appellee, 270 F.2d 23 (5th Cir. 1959)

The district court held valid five of the twenty-two claims of a patent granted to Keefe, entitled "Dry Powder Fire Extinguisher Apparatus,"¹  and held that the appellant had infringed three of those claims.² 

Dry powder fire extinguishers are used to extinguish fire by spreading over it finely divided particles of dry chemical, usually sodium bicarbonate. They have been known since at least as early as 1904³  and employ old and well-recognized principles.

The extinguisher disclosed by the Keefe patent includes a cylindrical container for holding dry powder, the concave bottom of which is spherical, with a discharge or eduction tube extending from outside the container to a point inside and near the bottom, and means for introducing gas into the upper portion of the container. The novel features of the patent mainly relied on are:

1. A concave bottom with a spherical surface; together with

2. The entrance of the eduction tube slightly above or at substantially the principal focus of the spherical surface.⁴ 

The concave spherical bottom had been disclosed in many earlier patents of devices for containing and expelling liquids and powders.⁵  In all, or practically all, of those patents the discharge or eduction tube had extended to a point near the bottom of the container. If patentable invention exists, it must be found in the positioning of the intake end of the discharge or eduction tube.⁶ 

The specification describes the theory on which the invention is based as follows:

"The theory on which the invention is based in expelling powder from the powder container by means of pressure gas passing downwardly in an axial direction to the bottom of the container may be explained by reference to Fig. 4 of the drawings by analogy to the action of a concave spherical mirror. * * *

"The present invention has been developed on the theory that in the passage of a gas with dry powder entrained therein, to a concave semispherical surface, the gas and powder might come to a focus corresponding to the principal focus of a concave spherical mirror of the same curvature, provided that the passage of the gas and powder is in a direction parallel to the axis of the spherical surface or concave mirror and provided also that the powder and gas might be removed at substantially the principal focus so as not to interfere with the gas and powder traveling in the opposite direction, or, in other words, so as to prevent turbulence in the oncoming stream of gas and powder. * * *"

Appellee's expert, and indeed only witness, Dr. Roland G. Sturm, rejected that theory, and the district court also expressed its view "that the applicants were mistaken in the theory upon which they relied." We agree, however, with the district court that the theory is immaterial if the patent actually works as a new and useful device or method or improvement.⁷ 

Dr. Sturm insisted, for entirely different scientific reasons which he explained at length⁸  and which involved "pressure pulsations" and "collapsing vortices," that the patent described much the best location for the intake end of the discharge or eduction tube. Dr. Sturm's hypothesis was sharply disputed by appellant's vice-president, Charles H. Somers, and by its expert witness, Arthur B. Guise, who had tested similar devices having transparent walls. Again, it is the actuality and not the scientific theory which counts. Had the patentee in fact discovered as the best and most effective location for the end of the tube a critical point which would not be readily determined, perhaps through trial and error, by a person having ordinary skill in the art?

The principal focus as taught by the patent is located at the distance r/2 from the bottom of the container, where r is the radius of the spherical surface of the bottom. Dr. Sturm conducted tests at that point and higher up, but made no tests to determine if expulsion was more effective or less complete with the eduction tube placed nearer the bottom of the container than r/2.⁹  The appellant, on the other hand, had carefully tested its extinguisher, starting with the eduction tube in contact with the bottom and raising it with minute gradations through the whole range — below, at, and well above the point r/2. The appellee had known the results of the appellant's tests for more than a year before the trial, but made no effort to refute them except by the testimony of Dr. Sturm.¹⁰ 

Appellant's tests disclosed some results which might have been anticipated. When the end of the tube was in contact with the bottom of the container, there was room for a mere minimum of powder to enter the tube. The best results were not obtained until the tube was raised to a point where the area between the container bottom and the end of the tube at least equaled the cross-sectional inside area of the tube, so as not to block the flow of powder.¹¹  From that point upward, the results showed a gradual, evenly progressive drop of the percentage of discharge, with no point of criticality at r/2 or anywhere else. Extinguishers with flat bottoms, of course, have no point of focus. However, appellant's tests with flat-bottomed extinguishers produced results paralleling those obtained with round-bottom extinguishers.

It is significant that appellee's fire extinguishers were, to a large extent, manufactured in a "coffee-pot," flat-bottomed shape, rather than under the patent in suit. That conduct is hard to explain if the patent accomplished what is claimed for it. Indeed, it is inconceivable if the extravagant advance represented in the patent¹²  was even approximately true.

We are convinced that there was no new and useful device or method or improvement and no patentable invention. The judgment is therefore reversed with directions to enter judgment for the defendant, appellant here.

Reversed with directions.