SMIMADZU v. Electric Storage Battery Co.

• Decision Date: 06 October 1936
• Docket Number: No. 7727.,7727.
• Citation: 17 F. Supp. 42
• Parties: SMIMADZU et al. v. ELECTRIC STORAGE BATTERY CO.
• Court: U.S. District Court — Western District of Pennsylvania

17 F. Supp. 42

SMIMADZU et al. v. ELECTRIC STORAGE BATTERY CO.

No. 7727.

District Court, E. D. Pennsylvania.

October 6, 1936.

Edmund B. Whitcomb, of Toledo, Ohio, Joseph W. Henderson, of Philadelphia, Pa., George Whitefield Betts, Jr., and George Yamaoka, both of New York City, George H. Souther, of Niagara Falls, N. Y., and Carl F. Schaffer, of Toledo, Ohio, for plaintiffs.

Hugh M. Morris, of Wilmington, Del., A. B. Stoughton and E. S. W. Farnum, Jr., both of Philadelphia, Pa., and A. F. Kwis, of Cleveland, Ohio, for defendant.

KIRKPATRICK, District Judge.

This is a suit in equity for the infringement of six patents, Nos. 1,584,149; 1,584,150; 1,584,151; 1,584,152; 1,584,479; and 1,896,020, all of which have to do with the production of fine powder of lead by the abrasion of larger pieces of metallic lead in a dry state. Various claims of the six patents cover process, product, and apparatus. The claims in suit are 1 and 2 of 1,584,149; 1-4, 6, 8-17 of 1,584,150; 1-5 of 1,584,151; all claims of 1,584,152; 1-4 of 1,584,479; and 10 and 11 of 1,896,020.

The product is used in the manufacture of plates for storage batteries. These plates consist of thin grids upon which lead paste is spread. The base of the paste is the powder, to which are added certain ingredients with which we are not concerned. It has been the experience of the industry that unless the powder is exceedingly fine and uniform in texture the paste will crack, peel, or flake off from the grids when the battery is in use and thus shorten its life and impair its efficiency. The powder consists chemically of lead of which the greater part has undergone some degree of oxidation. The precise proportion in which pure lead and lead oxides appear in the mixture as well as the degree of oxidation are not important except as they affect its physical properties.

Until fifteen or twenty years ago, makers of storage batteries bought their powder. It was manufactured by various molten lead processes and consisted of finely divided litharge, red lead, or other of the higher oxides. It was far from satisfactory, lacking the requisite uniformity and fineness. The necessity of purchasing it from others added to manufacturing costs. These drawbacks combined to make the matter of obtaining the powder a major problem in the industry. It can readily be seen that the development of a process by which makers of storage batteries could, without prohibitive expense of installation, produce in their own plants and in commercial quantities a thoroughly satisfactory powder would be of immense advantage to the industry, and it is not surprising that manufacturers in various parts of the world were spending a good deal of time and effort toward this end.

History of the Invention.

A brief account of the development of the process involved in this suit will be useful, not only in fixing the date of invention, but also as a means of getting an understanding of its nature and the importance of its various elements.

Beginning about the middle of September, 1918, the plaintiff Genzo Shimadzu, the largest manufacturer of storage batteries in Japan, and the head of many other industries, started experimenting with the idea that pieces of lead or lead balls could be abraded into powder by tumbling them together in a revolving vessel. He tried out, successively, porcelain vessels borrowed from the pottery industry, wooden drums, with and without metallic linings, vertical grinders of the mortar type, and a large specially constructed iron drum. He made a great number of trials during September, October, and November of 1918. Most of the product obtained was too coarse and irregular to be of any use, though some small amount of "hopeful fine powder" was observed. He also tried separating the fine from the coarse after the product had left the mill, by means of an air blast — which worked well enough but left the residue of coarse powder as pure waste.

Finally in December, 1918, he hit upon the idea of directing an air blast directly into the vessel in which the lead was being abraded, and a large metal drum was constructed with an inlet for the air current and an outlet by which the fine powder could be blown out. After some experimentation the inlet was fitted with a tube extending into the drum, having nozzles so that the air could be blown directly upon the abrading masses. This apparatus was completed and first operated in March, 1919.

It was at once observed that the amount of the product increased tremendously. This was a development of the greatest importance. The mere knowledge of some process by which the right kind of powder could be produced in trifling amounts was of very little value to any one. The industry was looking for a way to make large quantities cheaply, and an invention which fell short of accomplishing that result would have been of academic interest only.

The increase in production was due to the fact that the air was an oxidizing agent, forming a brittle layer of oxidized lead upon the plastic surfaces of the balls, which easily abraded off leaving a fresh surface, upon which the process was continued until the balls were entirely pulverized.

It is possible that at that stage the plaintiff had no real appreciation of the importance of the oxidizing effect of the air current. He appears to have thought that the removal of the dust was the principal cause of the increase in production. There was some ground for this belief, since it was not unreasonable to think that as long as the dust remained in the drum it would act more or less as a lubricant for the surfaces of the balls. But certainly, with the scientific resources and expert assistance at his command, he must have known that oxidation would be accelerated by the introduction of the air current. How much more than that he knew is hard to say.

Full commercial realization of the process did not follow immediately upon the installation of the mill in Shimadzu's plant (which was in June, 1919). That came only after more experimenting. Although some mechanical improvements upon the apparatus were made, most of this work had to do with the speed of revolution of the mill and the force and volume of the air current. What was actually being worked out, whether consciously or otherwise, was a second and highly important element of the process, namely, temperature control. Production in satisfactory quantities depended upon abrading the balls to powder as rapidly as possible and that in turn depended upon determining and maintaining a temperature in the mill which would be high enough to produce rapid oxidation, but not so high as to melt the metal or to overoxidize the product. The mill was large enough to be used commercially, and the plaintiff's witnesses referred to this period as "industrial scale experimental research." It was carried on from June, 1919, through the spring of 1920. Long before its termination, successful operation was so assured that it was decided to build a plant solely for the production of powder by the new process. The construction of the new plant was started in April, 1920, was completed in June of the same year, and went into regular operation about that time.

I fix the date of invention and successful reduction to practice as not later than August, 1919, that being the date of the "powdering machine" having the construction shown in Figure 28 of Ishimura's notebook. Whether or not the plaintiff, even then, fully realized the chemical reaction which made his process a success is beside the point. He certainly knew by that time that, subject to working out of details, he would be able to obtain large quantities of a satisfactory product. That was his major interest as well as that of the industry. A research scientist would, undoubtedly, have centered his attention upon the chemical reaction involved, but Shimadzu was a practical commercial operator, and I think it clear that he had enough appreciation of what was necessary to obtain the desired result for me to fix the date of invention at or before the time referred to, which is all that is necessary for the purposes of this case.

The process was unquestionably invented when the idea of blowing an air blast into a rotating mill in which lead pieces were being abraded and keeping the whole at a controlled high temperature by means of regulating speed of revolution and air pressure had been evolved and successfully practiced, and this point had been reached well with the time fixed.

The Process Claims of the Patents, Particularly '150.

At this point it will be convenient to summarize the process claims of the American patents postponing discussion of the product claims until later.

The important patent is 1,584,150. Some of the process claims of this patent define the thing which the process produces as "a fine powder of lead suboxide intermingled with powdered metallic lead" (claims 1, 2, 3, 4, 6, and 8). The remainder define it as a finely divided powder containing a large proportion of oxidized lead without any mention of lead suboxide (claims 9, 10, 11, 12, and 13). Claim 7 is not in suit. Passing over the first group ("suboxide" process claims) for the present, claim 9 is typical of the second group. It calls for the following steps:

(1) Impinging a current of air on lead masses in a dry state; (2) abrading the lead masses; (3) controlling the temperature to obtain a finely divided powder containing a large proportion of oxidized lead.

Claims 10 and 13 fix the necessary temperature at above 60 degrees centigrade.

Claim 2 of '149 is another process claim of this type, referring to "a finely divided chemically reactive lead powder of such fineness and activity as to be readily changed chemically on exposure to air." The air current is introduced into the vessel for the purpose of removing the powder formed by attrition of the lead masses. This patent contains no suggestion of the oxidizing effect of the...