Appeal from the District Court of the United States for the Northern District of Ohio, Eastern Division; Samuel H. West, Judge.
Before HICKS and ALLEN, Circuit Judges, and LEDERLE, District Judge.
Suit by the Commercial Shearing & Stamping Company, appellant, against the Youngston Steel Car Corporation, appellee, for infringement of claim 1 of letters patent No. 1,757,813, May 6, 1930, to Robert V. Proctor and Harry M. Schaab for a "tunnel liner"; and of claim 3 of letters patent No. 1,778,606, October 14, 1930, to Robert V. Proctor for a "metallic structure." Both patents were assigned to appellant.
The defenses were: Noninfringement, noninvention, anticipation, and estoppel. The court ruled that there was no infringement of either claim. Each patent related to tunnel lining.
For years it had been the practice in driving a tunnel, particularly through soft ground, to support the roof with timbers until a permanent lining of brick or concrete could be constructed. This practice was dangerous and called for working under the most cramped circumstances. Moreover, the timber was so heavy and thick, that much additional excavation was necessary to make room for it outside of the dimensions required for the permanent tunnel, necessitating the additional expense of filling in this large useless space around the tunnel barrel.
It is obvious that the wastes, dangers, and inconvenience of this type of tunneling could be reduced if an inexpensive metal support, possessing the strength of the timber and without its balk, could be developed. A metal support was in use prior to Proctor and Schaab. As early as 1913 Chamberlain, a tunnel engineer, used a tunnel lining consisting of successive rings or courses of steel plates with flanges and arched to the curve of the tunnel. Except for the curve, due to the arching, these plates had the appearance of shallow metal boxes, the flanges being their sides. The side flanges of the plate were parallel, but those at the ends were not, being perpendicular to the arch of the plate proper. There was a slit at each corner between the ends of the flanges where the metal had been cut out to permit bending. These plates were bolted together, side to side, through holes in the side flanges, to the previously constructed arch ring and end to end to each other through holes in the end flanges, to form an arch around the upper part of the tunnel heading. Thus, as the excavation proceeded, the lining was extended plate by plate and arch ring by arch ring. If necessary, the liner plates were supported temporarily by trench jacks, mounted on a "needle beam," i.e., two sills bolted together and extending from the heading back into the completed tunnel, or, if the load was not too heavy, the jacks were supported by a single sill.
The plates used by Chamberlain were known as the "cut corner" or open corner plates. They were cold pressed out of steel plate. The Chamberlain lining was a decided improvement over the timbering process. It was less expensive both in the manufacture and application of its plates. It eliminated the added excavation necessary for placing the timbers and materially reduced the use of trench jacks. It afforded a greater degree of protection from "ravelling" or seepage from the top than did the timbering. The Chamberlain lining was well known to Proctor and Schaab. In their application filed February 26, 1927, they say: "It has heretofore been proposed to use steel plates bent to the radius of the outside of the tunnel wall. While these plates have had certain advantages over the old method of lining with wood, they have been disadvantageous in that they lacked stiffness across the corners. Moreover, trouble was frequently encountered at the corners of adjacent plates due to the presence of a small opening which allowed water and mud to seep through." Their problem was to remedy these disadvantages in Chamberlain by producing a cheaper liner plate, cold pressed, out of wrought metal which would more effectively resist the strains and stresses to which tunnel liner plates are subject and reduce the amount of jacking required in tunnel construction.
They produced a cold pressed wrought metal plate with integral flanges. It had no cut out corners. The flanges at the corners were unitary. The "three way corners" where the flange joined the plate were rounded and the flange corners at or near their edges were sharpened. When their plates were positioned in the tunnel by being bolted together, end to end and side to side, to the previously completed arch rings, through holes in their flanges, the lining thus completed would, we think, be an improvement over Chamberlain or the prior tunnel lining art. The contiguous flanges at the sharpened corners of the plates were mutually supporting and formed substantially tight joints. Thus, the lining as a whole would be strengthened to meet opposing incidental strains and stresses, and seepage would be reduced. But we need ...