Linde Air Products Co. v. Graver Tank & Mfg. Co.

• Decision Date: 06 June 1947
• Docket Number: No. 607.,607.
• Citation: 75 USPQ 231,86 F. Supp. 191
• Parties: LINDE AIR PRODUCTS CO. v. GRAVER TANK & MFG. CO., Inc. et al.
• Court: U.S. District Court — Northern District of Indiana

86 F. Supp. 191

75 USPQ 231

LINDE AIR PRODUCTS CO. v. GRAVER TANK & MFG. CO., Inc. et al.

No. 607.

United States District Court N. D. Indiana, Hammond Division.

June 6, 1947.

Cahill, Gordon, Zachry, & Reindel, New York City, Carlson, Pitzner, Hubbard, & Wolfe, Chicago, Ill., Crumpacker, May, Carlisle, & Beamer, South Bend, Ind., for plaintiff.

L. L. Bomberger, Hammond, Ind., McKeehan, Merrick, Arter & Stewart, Cleveland, Ohio, Wilkinson, Huxley, Byron & Knight, Chicago, Ill., Oberlin & Limbach, Cleveland, Ohio, for defendant.

SWYGERT, District Judge.

The first question to be decided in this case is: Did the patentees invent something patentable over the prior art of electric welding? If they did, two collateral questions arise: What constitutes their invention, and what are its boundaries?

The evidence on the first question is clear and convincing that Jones, Kennedy and Rotermund invented an important improvement in electric welding. Their method of welding differs vastly from electric-arc hand welding either of the bare rod or coated rod variety. Furthermore, an inventive-level difference exists between their method and the automatic welding method taught by Robinoff. The physical appearances surrounding the welding zone in the Jones et al. method of welding differ from those in any of the prior methods of electric-arc welding. In bare rod and coated rod hand welding, the electric arc creates a blinding glare, and there is a great amount of smoke and splatter. In the Robinoff clay flux method constant flashings occur, and the arc is always at least partially visible. While in contrast to the appearances of those methods, there is no glare, no open arc, no splatter, and very little, if any, smoke in the Jones et al. method.

The truly remarkable difference. however, between what Jones, Kennedy and Rotermund invented and what had gone on before is perhaps best manifested by the performance achievements of their invention. For instance, only through its use can plates as thick as two and one-half inches be welded in a single pass. Furthermore, the welding speeds made possible by it dwarf those of any other method, and the welds produced by it are of the highest quality in contrast to the great amount of porosity contained in the welds produced by the so-called clay flux process.

Moreover, the commercial success of the Jones et al. method is persuasive evidence that this method is an improvement over the prior known methods. It is true that this commercial success has been confined principally to the sale and use of Unionmelt No. 20 in contradistinction to other possible compositions taught by the patent. However, testimony by users of Unionmelt that the Jones et al. method permits faster welding, saves costs and constitutes a vast improvement over hand welding is highly convincing that the method under inquiry is an invention.

Since the patentees did invent something patentable over the prior art of electric welding, the collateral questions of what constitutes their invention, and what are its boundaries, become pertinent.

To answer these questions a basic issue in this case must be decided. That issue is whether a fundamental difference in phenomena exists between the Jones et al. method and all methods of electric are welding. If it could be said without equivocation that the electric current passing between the electrode and the base metal travels through a welding composition which is in a melted or liquid state and that no "electric arc" is present, then a different electrical phenomenon would exist and a radically new process in electric welding would have been discovered. But no such finding can be made. The evidence is persuasive that no such basic difference in phenomena is present in the Jones et al. method.

The inventors themselves did not initially conceive their invention as embodying any such radical departure from known phenomena. Historically, they saw the Robinoff clay flux process in operation at the Western Pipe and Steel Company. It was from that point in welding development that they began their experiments with welding compositions which they hoped would give a better weld than was being obtained by the Robinoff process, which undoubtedly involves an electric arc phenomenon. During the course of their experiments, they did evolve a composition or compositions which produced better welds. The operational use of their welding composition was the same as the clay flux in the Robinoff process; that is, from a purely operational standpoint, there was and is no difference between the Robinoff and the Jones et al. methods. In both methods, a deep layer of flux or welding composition is laid in the V formed by the beveled edges of the plates to be welded; a bare welding rod is fed down through this composition; and an electric current, which produces the heat to weld the plates, is conducted from the rod to the base metal. Thus, the physical operational steps in the two methods are identical.

In their first application for a patent, the patentees designated their invention as an "Improvement in Method of Electric Arc Welding and a Flux Therefor." The specification of this application is replete with references to the presence and use of an electric arc in the new method. It was only after they had assigned their rights in the invention to the plaintiff that the suggestion of a basically new kind of phenomena other than an arc began to be made.

When a deep layer of the patented welding composition is used, there is no visual evidence of an electric arc after the initial welding operation has begun. What actually occurs between the electrode and the base metal is hidden from view by the surrounding granular flux. Because one cannot see what is actually happening beneath the top layer of the flux in the normal welding operation, it is impossible to say with complete certainty that there is or is not an arc. Although some of the evidence submitted by the plaintiff indicates the presence of a phenomenon other than the electric arc, the plaintiff's expert witness, Dr. Doan, in effect admitted that the Jones et al. process involves an arc phenomenon. I am in accord with the following appraisal of his testimony stated in defendants' brief: "We submit that Dr. Doan's answers to the Court's questions, when considered together with his last-quoted testimony, amply establishes the following facts. In hand welding with a metallic electrode, the arc is initiated by making contact between the end of the electrode and the plate. The arc is immediately established and the arc consists of an ionized gaseous medium through which the current flows with bare rod and no flux, ionized particles of the air participate in the conducting gaseous medium, and are not conducive to the production of sound weld metal. With the coated electrode, however, any initial and momentary participation of air particles is immediately replaced by the coating of the electrode in ionized vapor state and thereby the air is excluded, resulting in the production of sound metal. Dr. Doan admits that this produces an arc of entirely different characteristics. Yet it is still an arc. The only difference between it and the unshielded arc is the result of the coating on the electrode providing the shielding means. Identically the same thing takes place under a deep layer of flux. When the arc is initially established before the flux is vaporized, some air particles are present in the ionized gaseous medium. Immediately, however, the flux becomes vaporized, participates in and surrounds the arc zone, and shielding takes place to produce sound weld metal. Yet Dr. Doan claims this is not the same arc that was initially established. Neither is it the case of the hand electrode, but in both cases it is still an arc and as such conducts the current from electrode to plate, and provides the requisite heat for the welding operation."

In addition to his oral testimony regarding the existence of an arc, Dr. Doan made this significant statement in his treatise entitled, "Conduction of Electric Current in an Ionized Gas or Liquid": "In the welding process of the Jones et al. patent the welding rod is negative and the plate positive (or vice versa) with the pool of fused composition between them. All of the pool is `ionized.' Current thus flows throughout the pool between rod and plate. The concentration of heat is greatest at the center or core of the pool, and the composition there is vaporized. The ions and electrons there having greater freedom of movement, a larger proportion of the current is made up of their charges. But throughout the pool, both in its vaporous core and surrounding liquid mantle, the mechanism of current conduction is basically the same, viz.: a progression of positive ions in one direction and of negative ions and electrons in the other."

Finally, I do not understand the plaintiff to dispute the view that its process involves the existence of an arc phenomenon. In its reply brief this concessionary statement appears: "Second, the process of the patent-there is contact, and a vaporous core or arc is entirely sealed in; * * *. The fact is that (this) * * * is directly within the teachings of the patent and it is the actual operation which takes place in the Unionmelt and Lincolnweld processes."

Granted then that an arc exists, the question remains whether it has different characteristics than the arcs employed in the processes taught by the prior art of electric welding. Considering the phenomenon per se, it would appear that the conduction of electric energy in an ionized element which is in a gaseous or vaporized state is common to all electric arcs. In that respect there is no difference between the arc in the Jones et al. process and any other arc. The difference is not in phenomena but in the element or elements constituting the "ionized" area of the arc operation and surrounding it. In bare rod welding, the...