Schiller v. Robertson

28 F.2d 301, 1928 U.S. Dist. LEXIS 1480
CourtDistrict Court, D. Maryland
DecidedSeptember 14, 1928
Docket1326
StatusPublished
Cited by4 cases

This text of 28 F.2d 301 (Schiller v. Robertson) is published on Counsel Stack Legal Research, covering District Court, D. Maryland primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Schiller v. Robertson, 28 F.2d 301, 1928 U.S. Dist. LEXIS 1480 (D. Md. 1928).

Opinion

SOPER, District Judge.

The complainants have filed a bill of complaint against the Commissioner of Patents, pursuant to the provisions of R. S. § 4915 (35 USCA § 63; Comp. St. § 9460), complaining that the Commissioner has wrongfully rejected two applications for patents, and praying for a decree directing him to issue patents thereon. The more important of the two applications relates to a method and an apparatus for sterilizing and purifying air by killing the bacteria therein. The other application relates to a method and an apparatus for transferring milk or other liquids from tank trucks by means of compressed air, which is- sterilized before coming in contact with the Eq~ uids by the method disclosed in the first-mentioned application.

The discovery was made in connection with the business of the Seott-Powell Dairies in Philadelphia, where an attempt was made some years ago to employ compressed air as a means for emptying the tank trucks received at the central plant, so that the milk might be removed therefrom and raised to a point in the plant for pasteurization, bottling, etc. Pumps were then in use for this purpose, but their use was accompanied by an excessive agitation, which was injurious *303 to the milk. An experiment was made to ascertain if the compressed air method could be substituted.

The apparatus first devised consisted of (1) a compressor; (2) an 8-ineh cylinder, connected therewith and used as an expansion tank; and (3) an 18-inch tank, in which the air was further expanded. The apparatus successfully served the purpose of elevating the milk, but it was found, upon tests, that the bacteria content of the air that was being used was much too great to permit its contact with the milk, as described.

After further change, the apparatus described in the patent specification was devised, and it was found to be efficient, not only to elevate the milk, but also to purify the air. The change consisted merely of introducing two additional tanks in the series. There were introduced (1) an expansion tank of 6 inches in diameter between the compressor ana the 8-ineh tank heretofore mentioned; and (2) a 10-inch expansion tank between the 8-ineh tank and the 18-inch tank in the old apparatus. In its completed and final form, the system consisted of four tanks following the compressor, and being 6, 8, 10, and 18 inches, respectively, in diameter. An expansion valve was placed between each pair of tanks, which permitted the air to pass through an adjustable orifice, so that in its passage through the system the air was gradually expanded from the time that it left the compressor until it reached the 18-ineh tank. From this point, after passage through an oil separator and a filter, the air was led by a pipe to the tank containing the milk to be lifted. The patent specification contains the following statement:

“Destruction of the bacteria is apparently effected by rapid expansion of the compressed air and heated air. We have not ascertained the exact degree of expansion required for destroying-the bacteria, but find that, with the compressor raising the temperature of the air to 150° F. or higher, expansion until the temperature .drops 80 degrees is sufficient. We prefer, however, to expand until the temperature drops to 40 degrees or slightly below. To effect that result, we prefer the form of apparatus disclosed in the drawings. The expansion tanks and the receiving tanks are 8 feet in length, the first expansion tank is 8 inches in diameter, the second 10 inches, the third 12 inches, and the receiving tank 18 inches, and the pipe leading from the compressor to the first expansion tank 2 inches in diameter. This apparatus is adjusted for a pressure of 45 pounds with the discharge closed. By use of the apparatus we produce air that is sterile and free from oil and other impurities. While we have described our invention as taking a particular form, it will be understood that the various parts of our invention may be changed without departing from the spirit thereof; and hence we do not limit ourselves to the precise construction set forth, but consider that we are at liberty to make such changes and alterations as fairly come within the scope of the appended claims.”

While the bill of complaint in the first case refers to eight claims, in the application the controversy has been limited to Claims 5, 6, 7, and 8. Claim 5, which is typical, is as follows:

“The herein described method of sterilizing air consisting in compressing air until its temperature is about 150° F. and expanding it until the temperature drops about 80 degrees.”

The evidence shows beyond any question that the substitution of the method of elevating milk by compressed air rather than by pump is of great benefit to the business. There is a very great saving of time in the operation, excessive agitation of the milk is eliminated, a material quantity of the milk lost in the former method is saved, and the operation is more cleanly and sanitary. The evidence shows that the cost of elevating the milk has been reduced from 44 cents per thousand pounds to 1.7 cents per thousand pounds. Since it is not possible to use compressed air, unless it is sterilized, the value of a cheap and easily operated apparatus is obvious.

It is also shown by the evidence that scientists do not understand t why sterilization of the air should result from relatively slight compression followed by relatively slight expansion of the air. The degree of pressure used is described in the specification in terms of the resulting temperature. The evidence shows that the air in the compressor is subjected to a pressure of about 3 atmospheres, or 45 pounds, and is then expanded through the several tanks until, in the receiving tank, the pressure has been reduced to about 2% atmospheres, or about 37 pounds. During the course of this expansion, the temperature of the air is reduced from 150° F. to 70° F. It is fair to say that sterilization of the air by this simple apparatus came as a surprise to persons skilled in . the art. Sines the result achieved is of considerable value and utility, the discovery would seem to rise to the dignity of invention; unless it has been anticipated in the prior *304 art, or unless the disclosures thereof were such as to suggest it.

The authorities, consisting of prior patents and scientific tests, which were cited against the application in the Patent Office during the progress of the ease, disclose that sterilization by heat and by pressure were well known. In every ease, however, the degree of heat or of pressure, or the duration thereof, was greatly in excess' of the means employed hy the inventors. The evidence shows clearly enough that a temperature of 150° was not thought sufficient to sterilize air, but that it was necessary to employ a temperature of at least 250° to 300° F. for one or two hours, or at least, according to some of the authorities, for an appreciable period. The reference of Moore & Hewlett on Applied Bacteriology, cited by the Patent Office, states that, if dry heat is used, there must be a temperature of 320° to 350° F. for a half hour at least, and, if moist heat is used, the temperature must be 230° to 239° F. for at least 15 minutes.

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28 F.2d 301, 1928 U.S. Dist. LEXIS 1480, Counsel Stack Legal Research, https://law.counselstack.com/opinion/schiller-v-robertson-mdd-1928.