Nash Engineering Co. v. Trane Co.
| Decision Date | 07 June 1927 |
| Docket Number | No. 2508.,2508. |
| Citation | 20 F.2d 439 |
| Parties | NASH ENGINEERING CO. v. TRANE CO. |
| Court | U.S. District Court — District of Massachusetts |
Louis W. Southgate and Chas. T. Hawley, both of Worcester, Mass., for plaintiff.
Arthur T. Holmes, of La Crosse, Wis., Samuel D. Elmore, of Boston, Mass., and Fred L. Chappell, of Kalamazoo, Mich., for defendant.
This is a suit for the infringement of three patents, viz. to Nash for displacement structure, No. 953,222, dated March 29, 1910; to Nash for pump and air compressor, No. 1,091,529, dated March 31, 1914; and the reissue patent to Jennings, No. 15,637, dated June 26, 1923.
It was heard at length in open court. At the conclusion of the arguments I gave an oral judgment, holding the first two patents valid and infringed. Decision on the Jennings patent was reserved. Subsequently, but before any decision had been made on the last patent, the defendant moved to reopen in order to set up a newly discovered German patent to Blank, No. 56,529, dated May 20, 1890. The allowance of this motion vacated the previous judgment, and to some extent required a re-examination of the whole case. Upon the admission of the German patent in evidence, the plaintiff conceded for the purposes of this suit that the first Nash patent was untenable in the face of it, and withdrew that patent. This leaves the suit as one on the second Nash patent and the Jennings patent. My oral opinion, much of which was devoted to the first Nash patent, is to be considered as withdrawn, and the present opinion as covering the whole case as finally presented.
As to the second Nash patent, this patent is upon a hydroturbine air pump. The device is described in the opinion of the Circuit Court of Appeals in a suit brought by this plaintiff against one Cashin (13 F.2d 718), so that a detailed description of it here is not necessary. The claims now in suit, the sixth and thirteenth, are designed to protect one feature of the invention, viz. the sealing ring of water. In the center of the second Nash pump was atmospheric pressure, and at the inlet was a partial vacuum. The tendency would be for air to suck back along the running edges, between the rotor and the casing, and thereby impair the operation of the pump. To prevent that, Nash carried out the casing into a circular recess corresponding to the rim of his rotor, adapted to catch and hold a ring of spinning water over the joint between the casing and the rotor. It undoubtedly greatly aids in the operation of the pump by preventing leakage of air.
The only patents which are urged as anticipating this idea are the first Nash patent, the Lake (English) patent, and the new German patent. In my opinion, neither of the two first named does so, and this is sufficiently clear not to require the difficult and lengthy description of the devices which would be necessary to a discussion of the point. The German patent shows a rotor having buckets around the circumference, the sides of the buckets run fairly close to the casing, and the casing has circular recesses. These recesses are not, however, concentric with the rotor. There is what appears to be a substantial clearance between the rotor and the casing, and this clearance is functional, designed to permit the mercury, which is the operating liquid, to pass through it under certain conditions. There is no mention in the patent of any sealing ring, such as is shown in the Nash device. If there be such a ring, it is accidental, and it must have a traversing motion in and out of the side of the rotor as the latter revolves. In both the Nash patent and the defendant's pump, the recess (or equivalent flange) which catches the water is concentric with the rotor and makes with it a close running fit. I am confident that the German device would require reconstruction with the sealing ring in mind to cause such a ring to exist and function with water as the liquid. There is no evidence that anybody before Nash had any such idea, and an earlier patent cannot be construed for purposes of anticipation in the light of later knowledge. See Hirschy Co. v. Wisconsin, etc., Co. (D. C.) 18 F.(2d) 347, at page 355. On all the evidence, I find and rule that the claims in suit are valid.
Turning to the defendant's pump, it is a hydroturbine embodying the underlying principles of the Nash inventions. I held it to be an infringement of the first Nash patent. The interior of its rotor, through which it discharges the air, is open to atmospheric pressure; the inlet is exposed to the partial vacuum of the heating system. The inner sides of the casing are flat, having no recess like those of the patent in suit; but from these flat sides there extend inward C-shaped flanges, integral with the casing, which are concentric with the rotor and make a close running fit with the inner side of its rim. The clearance between the rim and the flange corresponds with the clearance between the rim and the casing in the second Nash patent. The plaintiff contends that a whirling ring of water forms over this joint, which functions like the sealing ring of the patent, to prevent air from leaking back through the pump. The defendant denies that this is so.
In claim 6, the ports are explicitly specified by letter (e5) which implies a construction closely assimilating that of the patent; i. e., ports through the casing head intermittently opened to the "pockets" on the rotor. This construction is not used in the defendant's device. At the conclusion of the original arguments I was of opinion that this difference was unsubstantial, and that the claim was infringed, and I so expressed myself. But upon further reflection I think that I was in error on this point, and that, as the ports are essential to the operation of the device of the patent and are clearly included in the claim, the absence of them in the defendant's pump avoids infringement of this claim.
Claim 13 reads as follows:
The only elements in this claim which require discussion are (1) whether the defendant's rotor is "combined with a case chamber including a head having a recess to receive a rotating fluid," and (2) whether said head also has "a port located wholly within the boundary of said rim portion and connecting with said hillow (sic) interior, so as to retain a portion of the revolving fluid in the interior of the wheel to form a joint between said wheel and the case chamber wall."
As to (1): It is said for the defendant that the casing head of its pump has no "recess." That is true in the strict sense. As before stated, Nash made a recess by carrying out the head or side of the casing in a little jog, which catches and holds the sealing ring of water. The defendant does not do that; it makes the inside of the casing straight, and extends from the inner face of it, integral with it, a circular C flange, just under the rim of the rotor, so that there is a close running fit between the rim and the flange. On one side of this joint is atmospheric pressure, and on the other side a partial vacuum. The proper operation of the pump requires that air leakage at this point shall be controlled. The solid web of the wheel throws out and keeps a whirling ring of water over the joint between the rim of the wheel and this flange on the casing, and prevents leakage there. It is precisely the idea of the claim, carried out in substantially the same way. The defendant's construction is in my opinion the equivalent of that specified in the claim. See N. Y. Scaffolding Co. v. Chain Belt Co., 254 U. S. 32, 41 S. Ct. 21, 65 L. Ed. 116. The defendant insists that there is no whirling ring of water in its pump; that the break in the C flange would permit such a ring to escape. It is a sufficient answer to this contention to point out that the defendant has clearly shown such a sealing ring in its advertising cut of its pump in operation. In my opinion that cut correctly shows how the pump works.
As to (2): In the patent there are, as already noticed, ports in the casing heads which are intermittently opened and closed. They are located near enough to the center to be inside the ring of sealing water, so that it does not escape through them. In the defendant's structure there is a central opening through the casing of less diameter than the C flange. The casing head and the C flange retain the ring of sealing water as above described; and the air is discharged through the round opening in the center of the casing head. While the question is perhaps not free from doubt, I am of opinion that in this claim the word "port" is used in the sense of a discharge (or inlet) opening through the casing head located inside the sealing ring of water.
It follows that this claim is infringed.
The remaining patent in suit is that to Jennings, reissue No. 15,637, dated June 26, 1923, for wet vacuum pumping apparatus, original application filed June 15, 1917.
This patent has been carefully considered by my brother Lowell and by the Circuit Court of Appeals for this circuit in the previous suit here, already referred to, by the present plaintiff against one Cashin. 3 F. (2d) 686, 13 F.(2d) 718. The art to which the patent relates, and the general state of that art at the time when the patent was applied for, are clearly described in those opinions and need not be restated. Vacuum steam-heating systems were known as far back as 1882, when Williames took out a patent which may have been the...
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Trane Co. v. Nash Engineering Co.
...further evidence was received, and the case fully reargued, orally and on briefs. Judge Morton's final opinion of June 7, 1927, is in 20 F.(2d) 439 (D. C.). The course of the trial gives more than usual weight to this obviously careful and considered opinion of the learned and experienced j......
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