177 F. 401 | 7th Cir. | 1910
(after stating the facts as above). The specifications of the McMillan patent in suit (No. 319,267) state that ■the subject-matter of the invention is “improvements in steam boiler furnaces,” that it “relates to smok.e-burning- steam boiler furnaces,” and that its objects are (a) “complete combustion of the carbon given off from burning fuel while securing the full benefit of the heat generated by the burning gases,” and (b) “the protection of the boiler by the more equal distribution through it of the heat.” Numerous prior patents are in evidence, both domestic and foreign, purporting to be improvements in furnaces for steam boilers, for like object in burning the smoke without loss of heating efficiency; and each of the means or elements combined in the McMillan furnace is present in the combination of the Stevens patent No. 333,430, and in other patents to be mentioned, except as to the special arrangement, form, and capacity .of thé discharge flues. The claim of patentable novelty, therefore, is thus stated in the brief for appellant:
*405 “While McMillan did not propose a single new element in his construction, he did propose a combination which was novel and operated on a new principle; and he did secure results superior to any which had been previously attained."
These discharge flues are described in claims 1 and 2 of the patent as “'in tubular form” and “of such capacity as to secure free draft and insure complete combustion within the flues”; and the patentability of the combination rests, as we believe, on departure in this provision from the discharge flues in oilier furnace combinations of the prior art. Moreover, the Patent Office so ruled, in effect, upon the application in question, as the exhibit file wrapper and contents shows repeated rejections of the original claims upon reference to several of these prior patents (including the above cited Stevens patent) as anticipations, and that ultimate allowance was obtained after amending the claims by inserting the above-quoted statement of the functional capacity of these discharge flues in present claims 1 and 2.
The appellant’s bill alleging infringement of this patent was dismissed in the trial court, as stated in the opinion there filed, upon the ground that no infringement appeared in the appellee’s furnace. It was further contended, as the appellee contends on this appeal, that the patent was invalid for want of invention, and that issue is dis-. cussed in the opinion referred to. Determination thereof is not deemed needful, however, in aur view of the indubitable force of the evidence of prior art to limit the scope of any invention which may arise under the patent, so that the claims can neither he interpreted broadly, as sought in the appellant’s contention of novelty above quoted, nor as needful to uphold the present charge of infringement.
In the appellant’s brief, the McMillan device is aptly described as consisting of—
“throwing a roofing arch of masonry over the fire box, extending this arch hack to the bridge wall, making this bridge wall of very considerable thickness and eaxTyixxg it up to the roofing arch and perforating it with commodious flues which, as he explains in his patent, perform the functions of retorts; and by introdxieing a supplemental supply of air in such maimer as to mingle it with the burning gases as they enter those retort flues. The forward end of the boiler was located over the fire box, so that the heat, radiating through the roof of the latter would be utilized in raising the temperature of the water, the mu-ward end of the boiler extending over the usual so-called combustion chamber located back of the bridge wall.”
The fire box thus described appears in several prior patents, of like single fire-box type, having a roofing arch of masonry to protect the boiler from direct contact with the fire; and the bridge wall so appears and is without novelty, either in location, structure, or “thickness.” For means to discharge the gases and smoke — common to all furnace patents, with variations in form and location — the claims describe “discharge flues in tubular form” (mentioned in the specification as “a multiple number,” with three shown in the drawings), leading from the fire box through the bridge wall. Their function is stated to be twofold: (a) Clear passageway for the burning gases; and (b) retort action in consuming the smoke en route,- by means of the Heat retained in the bridge wall. The remaining provision is an air duct—
The furnaces made by the appellee, which are alleged to infringe the several claims of this patent, unquestionably have these elements in like combination for like object, except as follows: That the fire box is of the double fire-box t)?pe, having two arches, and for the discharge means a single flue through the bridge wall is adopted, which differs in form and greatly exceeds in size the aggregate of the flues shown in the patent; and it has two discharge openings from the double fire box — one for each fire. Were the appellant’s contention tenable that the patent combination was not only novel, but “operated on a new principle,” and was entitled to complete protection against equivalents, it might well be conceded that these variations therefrom would -furnish no escape from infringement. That contention, however, is predicated alone on the patentee’s arrangement, form, and capacity of discharge'means, and we believe the prior furnace patents referred to leave no room for the scope of invention claimed in its so-called retort action.
While the field of furnace art was crowded with devices to relieve the smoke nuisance, when the patentee undertook another improvement, it is undisputed that neither the prior attempts nor the devices in suit have completely solved the problem. Improvers in that direction are entitled, as of course, to all benefits conferred by the patent laws for any invention they' disclose; but monopoly beyond the limits of invention is neither authorized nor just. So, whatever improvement was disclosed by the patentee in the above-mentioned provision, monopoly thereof must be 'limited to the actual invention; and to that end we deem it sufficient to cite a few of the prior pátents, having'pertinent discharge means in like cotnbinations.
Stevens’ (United States) patent, No. 333,430, has the single fire box and roofing arch, thick bridge wall, and numerous small discharge flues leading from the fire box, mainly extending through the bridge wall, but a portion extending upward through the roofing arch. It provides an air supply also “to-perfect and iittensify’combustion.”
Bowé’s (United States) patent, No. 371,872, has no roofing arch for the fire box, but shows the thick bridge wall, with “two or more” tubular flues, described.as extending through it from the fire box to discharge the smoke and .gases, “concentrate the heat,’’...and serve to “complete the combustion”; and the Pratt and Palmer (United States) patent, No. 312,655, shows both single and double fire box, .with roofing arches, having a single discharge flue through the bridge wall.
Criner’s (United States) patent, No. 246,943, has the inclosed fire box and a large flue passage in the bridge wall for the discharge, with a supply of air to complete combustion; and Mcllhenny’s (United States) patent, No. 328,133, has like elements in combination.
Ileiser’s German patent, No. 5,430 (of 1879) is for a furnace — not shown with a steam boiler, but stated in the specifications as adaptable therewith — shows a single fire box and extremely thick bridge wall, with discharge means of greater capacity than those of the McMillan patent, which are specified as “retorts” and have that function alike
Without extending this opinion by further references to the prior art, we believe it clearly appears therefrom that no interpretation of the claims in suit is authorized, which excludes other improvers from using discharge flues serving as well for the so-called “retort action” mentioned in the patent as their function; and therefore that the appellee’s furnace, having a different form of structure within the prior art, docs not infringe. Its double fire box, of another type in the art, has advantages in better regulation of the firing and thus regulating the discharge of smoke and gas; and its greatly enlarged single discharge flue, with an opening from each fire, is within such prior art, adapted to the type of furnace, and not an appropriation of the patentee’s device.
The decree appealed from is therefore affirmed.