Fuller Co. v. Metal Arts Co.

276 F. Supp. 605, 155 U.S.P.Q. (BNA) 345, 1966 U.S. Dist. LEXIS 10270
CourtDistrict Court, S.D. Texas
DecidedMay 9, 1966
DocketCiv. A. No. 64-H-164
StatusPublished

This text of 276 F. Supp. 605 (Fuller Co. v. Metal Arts Co.) is published on Counsel Stack Legal Research, covering District Court, S.D. Texas primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Fuller Co. v. Metal Arts Co., 276 F. Supp. 605, 155 U.S.P.Q. (BNA) 345, 1966 U.S. Dist. LEXIS 10270 (S.D. Tex. 1966).

Opinion

FINDINGS OF FACT

INGRAHAM, District Judge.

1. This is a suit for the infringement of claims 1 and 2, being all of the claims, United States Letters Patent 2,784,038, entitled “Means for Pneumatically Conveying Plastic Particulate Material”. The patent in suit was issued on March 5, 1957, on an application for patent filed by George Schneider on January 11, 1956.

2. Plaintiff, Fuller Company, a corporation of Delaware, is the owner of the entire right, title and interest in and to the Schneider patent.

3. Defendant, Metal Arts Company, is a corporation of Texas having its principal place of business in Houston, Texas.

4. The invention of the Schneider patent relates to the field of low-pressure pneumatic conveying. Pneumatic conveying systems are used for the transportation of various types of particulate materials, and generally at least include the combination of a conduit through which air is moved, a fan or blower to move air through the conduit, and suitable means for feeding the material to be conveyed into the conduit. The material thus introduced is carried by the airstream through the conduit to a discharge point.

5. The patent in suit is concerned with the problem of “skinning”, that is, the formation of what are known in the industry as “streamers”, “ribbons”, “snake skin”, “rats nests” or “angel hair”. This phenomenon occurs when particles of certain types of plastics, such as some kinds of polyethylene, polypropylene, nylon, and the like, are conveyed in a pneumatic conveying system. The particles of plastic come into sliding contact with the interior wall of the conveyor conduit, leaving smears of plastic thereon. The kinetic energy of the moving particles is converted partly into heat because of this sliding contact with the walls, and the heat tends to melt succeeding smears together to form long streamers, sometimes reaching six feet (6') in length. These streamers then peel off the wall and are carried through the conduit, sometimes as loose balls, along with the particles of plastic being conveyed.

6. The formation of streamers or ribbons in the pneumatic conveying of particles of certain plastics is a serious problem, as these streamers tend to foul the injection molding and extrusion machines in which the conveyed particles of plastic are to be used, and to cause imperfections in the end products. If the same conveying system is used subsequently to convey plastic pellets of a different color or type, streamers of the color or type of plastic previously conveyed are likely to contaminate the color or purity of the later material.

7. In the years immediately prior to 1956, as polyethylene and other types of plastics subject to skinning came into widespread use, efforts were made to solve the problem of skinning by making the interior of the conveyor conduit more smooth. Efforts also were made to avoid skinning by adjusting the velocity of the conveying airstream, by grounding the conveyor pipe to eliminate assumed electrostatic charges, by using soft-walled plastic pipe, and by other means, but none of these efforts was wholly successful. In 1956, the view was widely held in the industry that skinning could be avoided if the interior of the conduit could be made sufficiently smooth, but skinning continued to occur in very smooth conduits under the most favorable conditions of velocity and pressure. A system comprising roughened inner surfaces for elimination of streamer formation would not have been obvious to a person skilled in the art as of the time of the invention.

8. The patent in suit solves the problem of skinning by providing a pneumatic conveyor in which the interior [607]*607wall of the conduit includes means for interfering with continuous sliding contact between the particles being conveyed and the interior walls of the conduit, and means for maintaining an abruptly descending velocity gradient between the main body of the airstream and the interior wall. These means consist of a multiplicity of rugae or small peaks distributed compactly on the interior wall. When particles of plastic are being conveyed, the rugae or peaks interfere with the sliding surface contact. The rugae create a drag effect on the edge of the conveyor airstream, thus maintaining an abruptly descending velocity gradient of the airstream spaced between the wall and the main body of the airstream. This velocity gradient causes a corresponding decrease in the velocity of the plastic particles as they approach the wall so that their kinetic energy is lessened before impact. The random peaks upon impact bite into and engage the elastic pellets, and this tends to start the particles spinning so that they roll rather than slide. In this spinning, the kinetic energy of their forward momentum is partly converted into rotational momentum instead of into heat. The peaks, or rugae, also serve their function by engaging the pellets over a smaller contact area, thus reducing the amount of contact with the wall. The net effect is to prevent the formation of streamers.

9. The idea of a pneumatic conveyor having a multiplicity of rugae on its inner wall to inhibit the formation of skins or streamers in the conveying of polyethylene or other materials having the property of skinning was first conceived by George Schneider, the patentee of the patent in suit. This concept was promptly reduced to practice by him through a series of experiments, and a few months later he applied for the patent in suit. Plaintiff has met with a high degree of commercial acceptance in selling pneumatic conveyors of the type covered by the patent, and patented systems have become widely accepted in the industry. Major chemical companies in the United States have taken licenses under the patent.

10. The patent in suit discloses that the multiplicity of rugae are provided by roughening the interior of the conveyoi' conduit, as by sandblasting, etching, or anodizing. These methods are capable of producing the rugae referred to in the claims and described in the specification and drawings. The subject matter of the claims is fully disclosed and described in the specification and drawings, and one skilled in the art can readily construct an operable patented system from them.

11. Defendant has introduced a number of prior art patents and publications. However, none of these patents or publications were concerned with the problem of skinning, nor do they propose or suggest that a pneumatic conveyor with rugae on the interior wall of the conveyor conduit would solve the problem. Several of them were issued long before the problem of skinning was known. None of them is the same apparatus as that of the patent, and all of them would have to be modified to perform in the way and to achieve the result of Schneider. The modifications which would have been necessary to solve the problem would not have been obvious to one skilled in the art. These things are true of the German reference, patent No. 629,-891, issued May 15, 1936, cited in the patent, the Belgian reference, patent No. 536,238, dated in 1955, the Toulmin reference, patent No. 245,584, issued August 9, 1881, the Hoelzel reference, patent No. 2,834,059, issued May 13, 1958, and the other references cited by the defendant. The references do not anticipate the patent, whether considered singly or together.

12. The defendant attempted to show prior public use of the invention at a Monsanto Chemical Company plant in Connecticut, but the evidence on this subject was in conflict at most points and was not satisfactory.

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Bluebook (online)
276 F. Supp. 605, 155 U.S.P.Q. (BNA) 345, 1966 U.S. Dist. LEXIS 10270, Counsel Stack Legal Research, https://law.counselstack.com/opinion/fuller-co-v-metal-arts-co-txsd-1966.