Appeal from the District Court of the United States for the Western district of Pennsylvania; Nelson McVicar, Judge.
Before WOOLLEY and DAVIS, Circuit Judges, and JOHNSON, District Judge.
Reissue Patent No. 16,826 was granted to Stein in 1927 on an original application filed in 1919 and by mesne assignments was acquired by the plaintiff, in whom, we find on the threshold, rested the title at the time of the alleged infringement and the bringing of this suit. The patent is for a "Recuperative Furnace" and relates to soaking pits, having for its object "a vertical continuously recuperative furnace intended more particularly for the reheating of ingots to the temperature necessary for forging or rolling."
When molten steel is drawn from a furnace it is placed in molds and allowed to solidify in the form of ingots. They are then of uneven temperature, being relatively cold and hard on the surface and molten in the center. In order to be rolled they must be of uniform temperature throughout. To accomplish this, they were, years ago, placed in a pit -- positioned underground and located between the furnace and mill -- and allowed to attain, by gradual heat absorption, their own uniformity of temperature. This was called "soaking," hence the name "soaking pit." Later, to speed up production and insure a more uniform ingot temperature, the pits were heated.
The fuel used was gas, aided in its combustion by air preheated in a regenerator consisting of at least two chambers of refractory bricks placed in piles and arranged in checker fashion. Over the bricks in one chamber hot burnt gases from the pit furnace passed on their way out and imparted heat to the bricks. The hot exhaust gases were after a few minutes reversed to the other chamber (always with a corresponding reversal of flame in the furnace), and cold air drawn from outside passed over the hot bricks, became heated and then flowed on to meet the fuel gas on entering the furnace, as illustrated in Swindell, No. 327, 618 and Talbot, No. 571,250. This alternating process went on until the ingots reached a proper temperature, when they were withdrawn by a crane and sent to the rolls. Other ingots just taken from the molds were put in their place, heated and in turn withdrawn, thus effecting a continuous operation. In this manner waste gases were salvaged, the ingots were heated more uniformly and were capable of being held in the pit at the proper rolling temperature until wanted.Great as was the increase in production and facility of operation effected by this advance in the art, there was, nevertheless, a relatively low ingot capacity measured in respect to available floor space, heating that was not always uniform, poor fuel economy, and excessive slagging and scaling. Thus until 1926 or 1927, with the possible exception of the Schmid and DesGraz patent providing a one-way flame passing in at one side of the pit and out at the opposite side, the standard commercial soaking pit in the United States, operating on the regenerative principle of gas and heated air being alternately projected into the heating chamber from opposite sides, remained fixed. Except in details of construction, all soaking pits "were in form and principle * * * alike." Indeed for forty or fifty years, this great art remained static until Stein entered it with the new idea of the patent in suit. This had to do not with an aggregation but with a combination of parts, including a recuperator from which to obtain preheated air, an essential element of the operation, coacting with the fuel gas supplied to a furnace of a particular construction, causing a continuous flame to travel in a peculiar pathway. As indicated repeatedly in the specification and expressly stated in the two claims, 5 and 8, in suit, it is a "vertical" furnace and is thus distinguished from sloping and horizontal furnaces and comprises seven elements:
(1) A hearth or heating chamber vertical in character and arranged to receive and contain ingots standing erect so they may be dropped in for heating and drawn out by a crane preliminarily to rolling or forging; (2) means for admitting and burning in the hearth a combustible mixture of gas and air; (3) means for exhausting the products of combustion; (4) both being located in the same sidewall of the furnace, the admitting means being located above the exhausting means; (5) a recuperator through which the incoming air passes and through which the outgoing products of combustion pass for heating the air; (6) a smoke collector for the final exhaustion of the products of combustion, (7) provided with means (damper) for regulating the exhaust.
The novel conception of this invention, as we see it, is in providing in a soaking pit an all-enveloping flame moving always in one direction down the entire length of the ingot to replace the flame without form, intermittently interrupted and reversed in the prior art. The means to produce such a flame are a heating chamber somewhat in the form of a horseshoe with the live gas inlet and the burnt gas outlet on the same side of the chamber, the latter below the former, and provision for a steady flow of gas and preheated air, without reversal or pulsation, from an instrumentality which will do that thing, such as a recuperator, in which (distinguished from a regenerator) the hot exhaust on its way out is sent through pipes over which cold incoming air passes and picks up the heat. The result in the chamber of this shape with ports so positioned is a continuously descending helical flame, uniform in its intensity and reaching equally every part of the ingots without directly impinging on them.
In 1919 the plaintiff's predecessor, engaged in the manufacture of gas producers, resolved to extend its business to furnaces and accordingly sent an official abroad to look for an improved type. Eventually the Stein patent was bought and exploited. Realizing that in a steel plant the soaking pit operation is "the neck of the bottle," since no more ingots can be cast or rolled than can be passed through the soaking pits, the plaintiff thought that a furnace which would turn out more and better heated ingots and thereby save floor space and operating costs would find a ready market. The art, however, was satisfied with what it had. Being such a radical departure from the practice that had persisted for nearly half a century, the art accorded the Stein furnace a cold reception. Nearly all the large steel companies in the United States were approached, and for a time all turned it down. Eventually, the donner Steel Company, in 1926, was induced to install a single experimental "hole" of the Stein type and then only on condition that the plaintiff would stand one-half of the expense, the ordinary cost being about $20,000 a hole. From this it is clear the invention, if such it was, did not enter a crowded art. Instead of being crowded, it, in truth, contained a singular dearth of invention. Entering an art which had at least come to a standstill, the Stein furnace had to prove itself. After the Donner hole had been completed and operated, however, the art began to take notice of it. Slowly more installations were made, and finally the art openly accepted it on a showing that the Stein furnace increases ingot capacity from 50% to 100%; effects a fuel saving of from 20% to 25%; insures a more uniform ingot heat; enables better temperature regulation and makes a substantial reduction in maintenance costs. On these demonstrations the plaintiff's business in Stein soaking pit installations jumped from nothing to $600,000 in the two years preceding the trial with about a $1,000,000 of business in prospect.
Thereupon the Rust Engineering Company, a manufacturer since 1917 of standard regenerative soaking pits, entered the plaintiff's field. Realizing, as it must, that the only recuperative soaking pits with a one-way flame installed in this country at that date were those installed by the plaintiff under the Stein patent, it, nevertheless -- against timely warnings by the plaintiff -- advertised "The Rust-Amco Recuperative Pit Furnace," "The Rust One-Way Fired Soaking Pit," speaking of "the advantages of the Recuperative Pit Furnace versus the Regenerative Pit Furnace" and by words and diagrams showed substantially the furnace of the Stein patent. It hired six or seven important men who had previously been employed by the plaintiff and who had made the Donner installation and advertised its qualification to make the new installation by saying: "If you will remember that the men of our organization designed and sold all the refractory tile recuperative pits ever built in the United States," naming a price "considerably lower than you can erect * * * the refractory tile recuperative pit"; that we "have presented you a pit using the same principle in firing," etc.
At last the Rust Engineering Company succeeded in obtaining a contract with the Crucible Steel Company for an installation of a pit of the kind it had advertised.That is the infringing act here complained of. Moreover, at the time of trial it had outstanding bids for like furnaces in the sum of $487,735.
Then the plaintiff brought this action for infringement and had a decree holding the claims in suit valid and infringed. The defendant took this appeal, raising here on review the defenses it had interposed below, of which we shall discuss but two, namely, invalidity because of anticipation, prior publication and, perhaps, for want of invention; and non-infringement.
On the issues of anticipation and prior publication the defendant deals with two patents and one publication, ...