Appeal from the District Court of the United States for the District of Delaware; John P. Nields, Judge.
Before BUFFINGTON, WOOLLEY, and DAVIS, Circuit Judges.
This is an appeal and cross-appeal from a decree of the District Court, dismissing the complaint in a suit charging the defendants, Delaware Electric & Supply Company and Decatur Pump Company, with infringement of the reissue of United States letters patent No. 16,074, for a rotary pump, issued on May 19, 1925, to Adolph Wahle of Iowa.The original patent, No. 1,228,267, was issued to Wahle on May 29, 1917. The plaintiff was the exclusive licensee of Wahle until June 19, 1929, when Wahle assigned his patent to it. Suit was brought on July 9, 1929, against the Delaware Electric & Supply Company, a dealer in pumps, but the Decatur Pump Company, the manufacturer, intervened, and has assumed and conducted the entire defense. The defendants appellees will be referred to as defendant, meaning the Decatur Pump Company, and the appellant will be referred to as the plaintiff.
The reissue has twelve claims, the eight of the original patent and four others, but only claims 3 and 6 of the original patent are in issue. They read as follows:
3. "In a rotary pump, a casing having a passage extending circumferentially from a suitable inlet to a suitable outlet located adjacent thereon and having a circumferential slot in the annular transverse partition constituting the inner circumference of the same, of a rotor the axis of which is concentric to the center from which said axis is struck and which has an outer marginal portion which extends through said slot into said passage and is provided with a series of buckets therein each having a substantially flat bottom inclining from the periphery to the side thereof at a point adjacent said annular partition and separated by transverse blades."
6. "In a rotary pump, a casing consisting of two circular sections, one of which has a cylindrical rim projecting from its transverse web, and an annular flange projecting from said web in the same direction as said rim and between the same and its axis and has a suitable inlet opening in said rim and a discharge opening therein adjacent thereto but separated therefrom by a transverse partition, and the other section of which closes the open side of said first mentioned section and has an annular flange projecting sidewise toward and is the same diameter as the annular flange of the other section, in combination with a shaft journaled in suitable bearings in the center of said first-mentioned section, and a rotor securely mounted thereon within said section and having its marginal portion extending between said annular flanges into the circumferential passage between said annular flanges and said rim and provided with a series of buckets therein each having a substantially flat bottom inclining from the periphery to the side thereof at a point adjacent said annular partition and separated by transverse blades."
The following defenses were interposed: (1) Invalidity of the patent; (2) noninfringement of the claims in issue, and (3) laches of the plaintiff in bringing suit.
The learned trial judge found the claims to be valid and infringed, but held that the plaintiff had been guilty of laches, and so refused an injunction and an accounting, and accordingly dismissed the bill of complaint.
The plaintiff appealed from that portion of the decree which sustained the defense of laches and the denial of an injunction, and the defendant appealed from that portion which held claims 3 and 6 valid and infringed.
We therefore necessarily have one question before us for decision, the validity of the claims. If they are held to be invalid, that disposes of the entire case, but, if they are valid, then one or both of the other two questions, infringement and laches, must be considered.
The patent relates to that class of rotary pumps which employs what is known as an overshot rotor. The pump comprises a casing and rotor as its principal features. In the ordinary rotary pump, water engages the buckets or blades only once, but in the course of the water through the passageway between the inlet and outlet of the casing, in the Wahle pump, it is repeatedly engaged by the buckets or blades of the rotor, and its pressure and velocity are thus and thereby constantly increased. This constitutes a new type of rotary pump. As the District Judge said: "While Wahle was not a pioneer in the sense of creating a new art, he was a pioneer in his class," not of creating a new centrifugal pump, but of creating "an entirely new type of such pump, having an entirely new mode of operation."
The mechanism, method, and principle of operation of the pumps of the plaintiff and defendant are fully set forth in the clear and comprehensive opinion of the learned District Judge. While there is some difference in the construction and location of the buckets in the two pumps, we think that the action of the rotor upon the water in both pumps is substantially the same.
Being an improvement substantially advancing the art, the patent should be construed liberally, Eibel Process Company v. Minnesota & Ontario Paper Company, 261 U.S. 45, 63, 43 S. Ct. 322, 67 L. Ed. 523. and, when so construed, we are satisfied that, for the reasons set ...