724 F.2d 951 (Fed. Cir. 1983), 83-851, Raytheon Co. v. Roper Corp.

Docket Nº:Appeal Nos. 83-851, 83-853.
Citation:724 F.2d 951
Party Name:220 U.S.P.Q. 592 RAYTHEON COMPANY, Appellee/Cross-Appellant, v. ROPER CORPORATION, Appellant/Cross-Appellee.
Case Date:December 30, 1983
Court:United States Courts of Appeals, Court of Appeals for the Federal Circuit

Page 951

724 F.2d 951 (Fed. Cir. 1983)

220 U.S.P.Q. 592

RAYTHEON COMPANY, Appellee/Cross-Appellant,


ROPER CORPORATION, Appellant/Cross-Appellee.

Appeal Nos. 83-851, 83-853.

United States Court of Appeals, Federal Circuit

December 30, 1983

Page 952

Frank P. Porcelli, Boston, Mass., argued for appellant. With him on the brief were W.R. Hulbert and John M. Skenyon, Boston, Mass.

Martin J. O'Donnell, Boston, Mass., argued for appellee. With him on the brief were Robert A. Cesari and Steven J. Henry, Boston, Mass., Joseph D. Pannone and William R. Clark, Lexington, Mass., of counsel.

Page 953

Before MARKEY, Chief Judge, DAVIS, Circuit Judge, and KELLAM, Senior District Judge. [*]

MARKEY, Chief Judge.

Roper Corporation (Roper) appeals from a judgment of the United States District Court for the District of Massachusetts declaring U.S. Patent No. 4,028,520 ('520 patent), issued to Sumner H. Torrey and assigned to Roper, invalid for lack of utility and because its disclosure is non-enabling. Raytheon Company (Raytheon) cross-appeals a holding of nonobviousness, a finding of infringement, and a refusal to award attorney fees. We reverse in part, affirm in part, and remand.


  1. Prior Technology

    The Roper patent is directed to a "common cavity" oven capable of conventional thermal cooking, microwave cooking, and pyrolytic self-cleaning (i.e., heating the walls to about 900? F. to break down soil baked thereon). Those three "modes" of operation (thermal cooking, microwave cooking, and self-cleaning) are not totally compatible.

    At the time of the Torrey invention, cooking in a thermal oven required minimal amounts of air. Ventilation of thermal oven cavities was accomplished through an opening in the oven door, air flowing by natural convection from the opening upwardly through the cavity and escaping via a vent at the top of the cavity.

    Microwave cooking involved radiation supplied by a microwave feed unit. The feed unit included a magnetron generating radiation and an antenna transmitting the radiation to the oven cavity. The radiation travelled from the magnetron to the antenna through a hollow metal tube called a waveguide. The magnetron had projecting fins to help dissipate heat. A fan or blower moved cooling air through the magnetron fins and power supply.

    Microwave cooking produced more moisture than thermal cooking. To remove moisture vapors from the cavity of a conventional microwave oven, a blower or fan was employed to blow them out a vent at the cavity top. Microwave cooking also required maximum sealing of the cavity to prevent escape of microwave energy. Thus, the opening in the oven door of a thermal oven was not desirable in a microwave oven.

    Inclusion of a self-cleaning mode further complicated the ventilation of an oven operable in the thermal and microwave modes. Though a limited air supply was needed to flush smoke and volatile products of self-cleaning, excess air caused combustion of those products. That combustion, known as "autoignition", produced sudden pressure that sought release through any opening, including "backflow" through the waveguide. Although autoignition occurred only occasionally, backflow was thought to contaminate ("foul") the waveguide with burnt food particles cleaned from the cavity walls. Moreover, if autoignition were fueled by even greater amounts of excess air, as when forced air removed moisture produced in the microwave mode, fire or explosion could result.

    Self-cleaning common cavity ovens were first marketed in the mid-1960's, but by 1973, the General Electric and Litton ovens on the market still had ventilation problems. To meet those problems, the ends of the waveguides in those ovens were sealed to prevent fouling of the microwave feed unit by autoignition and backflow. As a result, moisture and steam developed in the microwave mode could not be removed by forcing air to the cavity through the waveguide. General Electric and Litton regarded this problem as serious enough to require customer warnings in their product manuals.

  2. The Torrey Invention

    In 1973, Roper began work on a self-cleaning common cavity oven. Under Torrey's

    Page 954

    supervision, Roper developed an oven with proper ventilation during the microwave, thermal, and self-cleaning modes, and which, to Torrey's surprise, had no fouling problems.

    In the summer of 1976, Roper marketed its oven nationally under its own name and through Sears, Roebuck & Company under the Kenmore label. About 24,000 have been sold, with no complaints respecting contamination of the microwave feed system. The Roper oven was and is a successful product.

    Torrey's February 26, 1976 application for patent issued without amendment as the '520 patent on June 7, 1977. The patented invention is depicted by this simplified drawing, shown alongside a simplified drawing of the accused Raytheon oven:


    In the Torrey invention, the microwave entry is located at the bottom of the oven cavity. Air to remove microwave cooking moisture is forced into the cavity through the microwave system. A pattern of small passages is provided in the wall of the waveguide so that a portion of the air from the blower, which cools the magnetron, flows through the waveguide and hollow conductor. When the blower is on, the air path is from the waveguide, through the cavity and venting through the top. When the blower is off, during thermal cooking and self-cleaning, convected air ventilates the cavity via the same path. The small passages are sufficiently screened to avoid leakage of radiation. The patent specification discloses a forced air flow of three to eight cubic feet per minute (cfm), and a convection flow of 0.5 to 2.0 cfm.

    There are five independent and two dependent claims in the '520 patent. Claim 5, on which claims 6 and 7 depend, is representative:

    5. In a combined microwave-thermal range, the combination comprising a frame having walls defining a rectangular oven cavity and a lower space of conforming shape, a door enclosing and sealing the front surface of the cavity against passage of air and microwave energy, a thermal element in the cavity, control means for operation of the thermal element within a normal temperature range for food preparation and at a high temperature level for a self-cleaning mode, the walls of the cavity being insulated,

    Page 955

    the bottom wall of the cavity having an inlet opening, means defining a cavity air vent at the top of the cavity, a microwave power supply having a housing including a magnetron and blower, the blower having a blower inlet and arranged to draw in cooling air for discharge under slight pressure to the magnetron, a waveguide having an inlet connected to the magnetron and extending under the bottom wall of the cavity to terminate at an outlet, means for connecting the outlet of the waveguide to the inlet opening of the cavity for conduction of microwave energy into the cavity, the waveguide being open to passage of cooling air from the magnetron so at least a portion of the pressurized air from the blower and magnetron passes through the waveguide and into the cavity for ventilating the cavity when the magnetron and blower are turned on, the blower inlet being located at a level below the bottom wall of the cavity so that when the blower and magnetron are turned off and the thermal element is turned on air is thermally convected through the blower inlet, magnetron, and waveguide into the cavity for final exit through the cavity air vent at the top thereof, the air passage through the blower, magnetron and waveguide being sufficiently constricted so that the air is convected in the self-cleaning mode at a level below that which is capable of producing an explosive reaction with the products of thermal decomposition.

    All claims are reproduced in the Appendix.

  3. District Court Proceedings

    On September 9, 1980, Raytheon sued for a declaratory judgment that the '520 patent was invalid. Roper counterclaimed for infringement of all claims. After trial without a jury, the district court issued an opinion on January 20, 1983, and a judgment on January 28, 1983.

    The district court declared the patent invalid because of a lack of utility required by 35 U.S.C. Sec. 101 1 and the absence of enabling disclosure required by 35 U.S.C. Sec. 112. 2 The district court also found that the Torrey invention was a commercial success, held that the invention would have been nonobvious, 3 and found that if the claims were valid, Raytheon would be liable for having infringed them. 4

    Because the case was not in its view an "exceptional" one, as required by 35 U.S.C. Sec. 285, 5 the district court refused to award attorney fees to Raytheon.


    Did the district court err in (1) its judgment of invalidity under 35 U.S.C. Secs. 101 and 112; (2) its holding of nonobviousness under 35 U.S.C. Sec. 103; (3) its finding of infringement; (4) its failure to award attorney fees.

    Page 956


  4. Standard of Review

    Raytheon argues the evidence de novo. As Roper correctly points out, this court does not review the fact record de novo. District court findings must be accepted unless they are predicated on an improper legal foundation, see, e.g., W.L. Gore & Associates, Inc. v. Garlock, Inc., 721 F.2d 1540 at 1547 (Fed.Cir.1983), or unless they are shown by the party challenging them to be "clearly erroneous", i.e., unless this court is left with the "definite and firm conviction that a mistake has been committed". Inwood Laboratories, Inc. v. Ives Laboratories, Inc., 456 U.S. 844, 855, 102 S.Ct. 2182, 2189, 72 L.Ed.2d 606 (1982). The clearly erroneous standard applies to findings, not to legal conclusions.

  5. ...

To continue reading