1 Opinion of the Court. ing the distance to the fluid surface in deep oil wells. A product of this experimentation was the Lehr and Wyatt patent, upon which the present patent claims to be an improvement. It proposed to measure the distance by measuring the time of travel of the echo of an "impulse wave" generated by a “sudden change in pressure." The apparatus described included a gas cylinder with a quick operating valve by means of which a short blast of gas could be injected into a well. It was stated in the patent that the time elapsing between the release of the gas and the return of the echo of the waves produced by it could be observed in any desired manner. But the patentee's application and drawings noted that the wave impulses could be recorded by use of a microphone which might include an amplifier and an appropriate device to record a picture of the wave impulses. This Lehr and Wyatt patent, it is therefore apparent, simply provided an apparatus composed of old and wellknown devices to measure the time required for pressure waves to move to and back from the fluid surface of an oil well. But the assumption that sound and pressure waves would travel in oil wells at open-air velocity of 1100 feet per second proved to be erroneous. this reason the time-velocity computation of Lehr and Wyatt for measuring the distance to the fluid surface produced inaccurate results. For After conferences with Lehr, Walker undertook to search for a method which would more accurately indicate the sound and pressure wave velocity in each well. Walker was familiar with the structure of oil wells. The oil flow pipe in a well, known as a tubing string, is jointed and where these joints occur there are collars or shoulders. There are also one or more relatively prominent projections on the oil flow pipe known as tubing catchers. Opinion of the Court. 329 U.S. In wells where the distance to the tubing catcher is known, Walker observed that the distance to the fluid surface could be measured by a simple time-distance proportion formula. For those wells in which the distance to the tubing catcher was unknown, Walker also suggested another idea. The sections of tubing pipe used in a given oil well are generally of equal length. Therefore the shoulders in a given well ordinarily are at equal intervals from each other. But the section length and therefore the interval may vary from well to well. Walker concluded that he could measure the unknown distance to the tubing catcher if he could observe and record the shoulder echo waves. Thus multiplication of the number of shoulders observed by the known length of a pipe section would produce the distance to the tubing catcher. With this distance, he could solve the distance to the fluid surface by the same proportion formula used when the distance to the tubing catcher was a matter of record. The Lehr and Wyatt instrument could record all these echo waves. But the potential usefulness of the echoes from the shoulders and the tubing catcher which their machine recorded had not occurred to Lehr and Wyatt and consequently they had made no effort better to observe and record them. Walker's contribution which he claims to be invention was in effect to add to Lehr and Wyatt's apparatus a wellknown device which would make the regularly appearing The known distance from well top to the tubing catcher is to the unknown distance from well top to the fluid surface as the time an echo requires to travel from the tubing catcher is to the time required for an echo to travel from the fluid surface. Walker's patent emphasizes that his invention solves the velocity of sound waves in wells of various pressures in which sound did not travel at open-air or a uniform speed. Mathematically, of course, his determination of the distance by proportions determines the distance to the fluid surface directly without necessarily considering velocity in feet per second as a factor. 1 Opinion of the Court. shoulder echo waves more prominent on the graph and easier to count. The device added was a mechanical acoustical resonator. This was a short pipe which would receive wave impulses at the mouth of the well. Walker's testimony was, and his specifications state, that by making the length of this tubal resonator one-third the length of the tubing joints, the resonator would serve as a tuner, adjusted to the frequency of the shoulder echo waves. It would simultaneously amplify these echo waves and eliminate unwanted echoes from other obstructions thus producing a clearer picture of the shoulder echo waves. His specifications show, attached to the tubal resonator, a coupler, the manipulation of which would adjust the length of the tube to one-third of the interval between shoulders in a particular well. His specifications and drawings also show the physical structure of a complete apparatus, designed to inject pressure impulses into a well, and to receive, note, record and time the impulse waves. The District Court held the claims here in suit valid upon its finding that Walker's "apparatus differs from and is an improvement over the prior art in the incorporation in such apparatus of a tuned acoustical means which performs the function of a sound filter . . ." The Circuit Court of Appeals affirmed this holding, stating that the trial court had found "that the only part of this patent constituting invention over the prior art is the 'tuned acoustical means which performs the functions of a sound filter.'" For our purpose in passing upon the sufficiency of the claims against prohibited indefiniteness we can accept without ratifying the findings of the lower court that the addition of "a tuned acoustical means" performing the "function of a sound filter" brought about a new patentable combination, even though it advanced only a narrow Opinion of the Court. 329 U.S. 5 step beyond Lehr and Wyatt's old combination. We must, however, determine whether, as petitioner charges, the claims here held valid run afoul of Rev. Stat. 4888 because they do not describe the invention but use "conveniently functional language at the exact point of novelty." General Electric Co. v. Wabash Appliance Corp., supra, at 371. Walker, in some of his claims, e. g., claims 2 and 3, does describe the tuned acoustical pipe as an integral part of his invention, showing its structure, its working arrangement in the alleged new combination, and the manner of its connection with the other parts. But no one of the claims on which this judgment rests has even suggested the physical structure of the acoustical resonator. No one of these claims describes the physical relation of the Walker addition to the old Lehr and Wyatt machine. No one of these claims describes the manner in which the Walker addition will operate together with the old Lehr and Wyatt machine so as to make the "new" unitary apparatus perform its designed function. Thus the claims failed adequately to depict the structure, mode, and operation of the parts in combination. A claim typical of all of those held valid only describes the resonator and its relation with the rest of the apparatus as "means associated with said pressure responsive device for tuning said receiving means to the frequency of echoes from the tubing collars of said tubing sections to clearly distinguish the echoes from said couplings from 5 See Hailes v. Van Wormer, 20 Wall. 353; Knapp v. Morss, 150 U. S. 221, 227-28; Textile Machine Works v. Louis Hirsch Textile Ma·chines, Inc., 302 U. S. 490; Lincoln Engineering Co. v. Stewart-Warner Corp., 303 U. S. 545, 549-50. • Halliburton does not challenge the adequacy of the description of any other features of the "new combination." The elements of Walker's apparatus other than the filter are so nearly identical to what Lehr and Wyatt patented that we can speak of these other elements as the "Lehr and Wyatt machine." 1 Opinion of the Court. each other." The language of the claim thus describes this most crucial element in the "new" combination in terms of what it will do rather than in terms of its own physical characteristics or its arrangement in the new combination apparatus. We have held that a claim with such a description of a product is invalid as a violation of Rev. Stat. 4888. Holland Furniture Co. v. Perkins Glue Co., 277 U. S. 245, 256-57; General Electric Co. v. Wabash Appliance Corp., supra. We understand that the Circuit Court of Appeals held that the same rigid standards of description required for product claims is not required for a combination patent embodying old elements only. We have a different view. Rev. Stat. 4888 pointedly provides that "in case of a machine, he [the patentee] shall explain the principle thereof, and the best mode in which he has contemplated applying that principle, so as to distinguish it from other inventions; and he shall particularly point out and distinctly claim the part, improvement, or combination which he claims as his invention or discovery." It has long been held that the word "machine" includes a combination. Corning v. Burden, 15 How. 252, 267. We are not persuaded that the public and those affected by patents "Both parties have used Claim 1 as a typical example for purposes of argument throughout the litigation. Other claims need not be set out. Claim 1 is as follows: "In an apparatus for determining the location of an obstruction in a well having therein a string of assembled tubing sections interconnected with each other by coupling collars, means communicating with said well for creating a pressure impulse in said well, echo receiving means including a pressure responsive device exposed to said well for receiving pressure impulses from the well and for measuring the lapse of time between the creation of the impulse and the arrival at said receiving means of the echo from said obstruction, and means associated with said pressure responsive device for tuning said receiving means to the frequency of echoes from the tubing collars of said tubing sections to clearly distinguish the echoes from said couplings from each other." |