2020001463 (P.T.A.B. Oct. 28, 2020)

United Technologies Corporation

Patent Trials and Appeals BoardOct 28, 2020

2020001463 (P.T.A.B. Oct. 28, 2020)

UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 15/025,949 03/30/2016 John E. Holowczak 67097-2678PUS1;63130US02 5893 54549 7590 10/28/2020 CARLSON, GASKEY & OLDS/PRATT & WHITNEY 400 West Maple Road Suite 350 Birmingham, MI 48009 EXAMINER LEGENDRE, CHRISTOPHER RYAN ART UNIT PAPER NUMBER 3745 NOTIFICATION DATE DELIVERY MODE 10/28/2020 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): ptodocket@cgolaw.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte JOHN E. HOLOWCZAK and MICHAEL G. MCCAFFREY Appeal 2020-001463 Application 15/025,949 Technology Center 3700 Before DANIEL S. SONG, CHARLES N. GREENHUT, and LEE L. STEPINA, Administrative Patent Judges. STEPINA, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the Examiner’s decision to reject claims 1–4 and 6–20. We have jurisdiction under 35 U.S.C. § 6(b). We reverse. 1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies United Technologies Corporation as the real party in interest. Appeal Br. 1. Appeal 2020-001463 Application 15/025,949 2 CLAIMED SUBJECT MATTER The claims are directed to a ceramic matrix composite (“CMC”) blade with a monolithic ceramic portion. Claim 1, reproduced below, is illustrative of the claimed subject matter. 1. A blade for a gas turbine engine comprising: a fiber reinforced ceramic matrix composite structure providing an airfoil with an exposed exterior airfoil surface; and a non-metallic, monolithic, isotropic refractory structure including a platform and providing at least an outer portion of a root secured relative to the airfoil. Appeal Br. 7 (Claims App.). REFERENCES The prior art relied upon by the Examiner is: Name Reference Date Morrison US 7,258,530 B2 Aug. 21, 2007 Carper US 7,329,101 B2 Feb. 12, 2008 Darkins US 2012/0163986 A1 June 28, 2012 Garcia-Crespo US 2014/0271208 A1 Sept. 18, 2014 Kleinow US 2016/0222800 A1 Aug. 4, 2016 REJECTIONS2 I. Claims 1–4 and 6–20 are rejected under 35 U.S.C. § 103(a) as unpatentable over Kleinow and Morrison. II. Claims 1, 6–8, and 11 are rejected under 35 U.S.C. § 103(a) as unpatentable over Darkins and Morrison. 2 In an Advisory Action dated March 8, 2019, the Examiner withdrew a rejection of claims 6–10, 19, and 20 under 35 U.S.C. § 112(b). See Final Act. 2; Advisory Act. 2. Appeal 2020-001463 Application 15/025,949 3 III. Claims 1, 6, and 9–11 are rejected under 35 U.S.C. § 103(a) as unpatentable over Garcia-Crespo and Morrison. IV. Claims 2–4, 12–16, 19, and 20 are rejected under 35 U.S.C. § 103(a) as unpatentable over Garcia-Crespo, Morrison, and Carper. V. Claims 7 and 8 are rejected under 35 U.S.C. § 103(a) as unpatentable over Garcia-Crespo, Morrison, and Darkins. VI. Claims 17 and 18 are rejected under 35 U.S.C. § 103(a) as unpatentable over Garcia-Crespo, Morrison, Carper, and Darkins. OPINION Rejection I, Kleinow and Morrison The Examiner finds that Kleinow discloses many of the elements recited in claim 1, including a refractory structure that includes a platform. See Final Act. 4. However, the Examiner finds Kleinow fails to disclose that its refractory structure is non-metallic, monolithic, and isotropic, as required by claim 1. Id. To address this deficiency, the Examiner finds Morrison teaches “it is known to form gas turbine engine components of monolithic ceramic since they exhibit isotropic shrinkage, thereby avoiding interlaminar stress failure.” Id. (citing Morrison 2:24–36). The Examiner reasons it would have been obvious to a person of ordinary skill in the art to modify Kleinow’s blade to include a “refractory structure of a monolithic ceramic (which is also non-metallic and isotropic), as disclosed by Morrison, for the purpose of providing heat-resistance (i.e., due to the ceramic) and avoiding interlaminar stress/failure.” Id. Appeal 2020-001463 Application 15/025,949 4 Appellant argues that, by indicating that monolithic ceramics lack the toughness necessary for such applications, Morrison teaches away from replacing structural CMC components with monolithic ones. Appeal Br. 3 (citing Morrison 1:16–20, 2:48–50). In response, the Examiner finds that Morrison merely expresses a preference for CMC materials over monolithic ceramics, and this preference is taught only in the context of certain structural members. Ans. 4–5 (citing Morrison 1:6–10, 18–25). Specifically, the Examiner finds that a blade, such as the gas turbine blade disclosed by Kleinow, “is not load-carrying (i.e., gas turbine engine rotor blades do not transfer, or carry, both tensile and compressive loads from one structure to another structure) and/or that gas turbine engine blades experience different types and/or magnitudes of stresses than stationary airfoil/ vanes.” Id. at 5. In other words, the Examiner finds that a person of ordinary skill in the art would understand that the blade disclosed by Kleinow does not experience the kind of structural loads that Morrison teaches are a problem for monolithic ceramics. Id. Further, the Examiner finds that Morrison’s disclosure regarding the use of monolithic ceramic amounts to a discussion of trade-offs (namely, strength and toughness versus high temperature capability, isotropic shrinkage, and absence of interlaminar strain). Id. (citing Morrison 2:20–22, 26–44). Based on these findings, the Examiner concludes “[a]lthough Morrison discloses use of CMC materials, one can envisage a set of design requirements prioritizing avoidance of --unacceptably high interlaminar strains-- that –may result in the formation of either undesirable voids or cracks-- in which monolithic ceramic material(s) could be preferable over CMC material(s).” Ans. 5–6. Appeal 2020-001463 Application 15/025,949 5 Whether a reference teaches away from a claimed invention is a question of fact. In re Harris, 409 F.3d 1339, 1341 (Fed. Cir. 2005). “A reference may be said to teach away when a person of ordinary skill, upon reading the reference, would be discouraged from following the path set out in the reference, or would be led in a direction divergent from the path that was taken by the applicant.” In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994). Considering Morrison’s disclosure as a whole, we find Appellant to have the better position as to whether this reference teaches away from the arrangement recited in claim 1. In its Background section, Morrison states: Ceramic materials are often used in high temperature applications such as the hot combustion gas path components of a gas turbine engine. Monolithic ceramic materials generally exhibit higher operating temperature limits than do metals, however they lack the toughness and tensile load carrying capabilities required for most structural applications. Ceramic matrix composite (CMC) materials are known to provide a combination of high temperature capability, strength and toughness. Morrison 1:14–22 (emphasis added). Morrison goes on to detail the implementation of CMC materials and a design technique used to address a known deficiency (interlaminar cracking) in such materials. See, e.g., id. at 2:4–3:31. Specifically, Morrison teaches implementing gap 26 to allow opposed end portions of an airfoil to move relative to each other. See id. at 2:48–62, Figs. 2A, 2B, 2C. Aside from the paragraph quoted above, Morrison uses the term “monolithic ceramic” only one other time, stating “[m]onolithic ceramics exhibit isotropic shrinkage.” Id. at 2:26–27. Morrison then explains that CMC materials exhibit anisotropic shrinkage due to the presences of fibers, and such shrinkage can lead to the above- Appeal 2020-001463 Application 15/025,949 6 noted interlaminar cracking (which Morrison addresses via the use of gap 26). In view of the disadvantage of monolithic ceramic materials disclosed in Morrison against the disclosed advantages, we agree with Appellant that Morrison would have led a person of ordinary skill in the art away from making Kleinow’s platform from monolithic ceramics. In this regard, Morrison’s statement that monolithic ceramics “lack the toughness and tensile load carrying capabilities required for most structural applications” amounts to a warning that these materials are inadequate for such applications. The fact that monolithic ceramics may be adequate (or even excel) in other aspects of airfoil design cannot make up for outright inadequacy in this critical aspect. Accordingly, we do not sustain the rejection of claim 1, and claims 2–4 and 6–10 depending therefrom, as unpatentable over Kleinow and Morrison. The Examiner’s use of the teachings of Morrison in rejecting claims 11–20 includes the same deficiency (see Final Act. 7), and, therefore, we do not sustain the rejection of these claims as unpatentable over Kleinow and Morrison. Rejection II–VI, Darkins, Garcia-Crespo, Carper, and Morrison The Examiner relies on the disclosure of Morrison in each of Rejections II–VI in the same manner as discussed above regarding Rejection I. See Final Act. 9–20. Accordingly, for the same reasons, we do not sustain Rejections II–VI. CONCLUSION The Examiner’s rejections are reversed. Appeal 2020-001463 Application 15/025,949 7 DECISION SUMMARY Claims Rejected 35 U.S.C. § Basis Affirmed Reversed 1–4, 6–20 103(a) Kleinow, Morrison 1–4, 6–20 1, 6–8, 11 103(a) Darkins, Morrison 1, 6–8, 11 1, 6, 9–11 103(a) Garcia-Crespo, Morrison 1, 6, 9–11 2–4, 12–16, 19, 20 103(a) Garcia-Crespo, Morrison, Carper 2–4, 12– 16, 19, 20 7, 8 103(a) Garcia-Crespo, Morrison, Darkins 7, 8 17, 18 103(a) Garcia-Crespo, Morrison, Carper, Darkins 17, 18 Overall Outcome 1–4, 6–20 REVERSED