Ex Parte HuDownload PDFBoard of Patent Appeals and InterferencesApr 16, 200910746388 (B.P.A.I. Apr. 16, 2009) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE ____________________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ____________________ Ex parte YIPING HU ____________________ Appeal 2008-4679 Application 10/746,388 Technology Center 3700 ____________________ Decided: 1April 16, 2009 ____________________ Before WILLIAM F. PATE III, JENNIFER D. BAHR and STEVEN D.A. McCARTHY, Administrative Patent Judges. McCARTHY, Administrative Patent Judge. DECISION ON APPEAL 1 The two month time period for filing an appeal or commencing a civil action, as recited in 37 CFR § 1.304 (2008), begins to run from the Decided Date shown on this page of the decision. The time period does not run from the Mail Date (paper delivery) or the Notification Date (electronic delivery). Appeal 2008-4679 Application 10/746,388 2 STATEMENT OF THE CASE 1 The Appellant appeals under 35 U.S.C. § 134 (2002) from the final 2 rejection of claims 1-4, 8, 10-12, 14, 17, 19-22 and 25 under 35 U.S.C. 3 § 103(a) as being unpatentable over Mukira (US 6,302,649 B1, issued Oct. 4 16, 2001), Peterson (US 6,364,971 B1, issued Apr. 2, 2002) and Cross (US 5 4,096,615, issued Jun. 27, 1978). We have jurisdiction under 35 U.S.C. 6 § 6(b) (2002). 7 We AFFIRM. 8 The claims on appeal relate to repairing high-strength superalloy 9 turbine blades. (Spec. 3, ¶ 0009). Independent claim 1 is typical of the 10 claims on appeal: 11 12 1. A method of repairing a damaged 13 region on a gas turbine engine turbine blade that is 14 constructed at least partially of a superalloy, 15 comprising the steps of: 16 welding the damaged region of the turbine 17 blade without preheating the damaged region using 18 either an electron beam welding process or a laser 19 welding process, whereby a weld seam having a 20 surface is formed; and 21 subjecting the welded turbine blade to a hot 22 isostatic pressing process, the hot isostatic process 23 carried out at about 2200°F and about 15 ksi, for 24 about 2 - 4 hours. 25 26 ISSUES 27 The Examiner finds that Mukira discloses repairing a superalloy 28 turbine engine blade using electron beam welding or laser welding processes 29 conducted at room temperature. (Ans. 3.) The Examiner finds that Peterson 30 describes repairing a superalloy turbine engine component by means of a 31 Appeal 2008-4679 Application 10/746,388 3 laser welding process followed by a hot isostatic pressing [“HIP”] process. 1 (Id.) The Examiner further finds that Cross teaches performing an HIP 2 process on a brazed turbine engine component at 2225°F and 15 ksi for 3 about 3-4 hours. (Ans. 3-4.) The Examiner concludes that it would have 4 been obvious to have repaired a turbine engine component using an electron 5 beam welding process or a laser welding process followed by an HIP 6 process conducted according to the parameters recited in claim 1 “because 7 the HIP process eliminates microcracking in the weld heat affected 8 zone . . . .” (Ans. 4.) 9 The Appellant presents only one argument directed against the 10 rejections of all of the claims on appeal, namely, that Mukira teaches away 11 from the claimed method because Mukira discloses the use of a solid 12 solution strengthened alloy composition which does not require a post-weld 13 HIP process to produce a good room temperature weld. (App. Br. 10; Reply 14 Br. 2.)2 Since all of the claims on appeal are subject to the same ground of 15 rejection and since the Appellant presents no arguments directed against the 16 rejection of claims 2-4, 8, 10-12, 14, 17, 19-22 and 25 separate from the 17 arguments directed against the rejection of claim 1, we select claim 1 as 18 representative of the claims on appeal. See 37 C.F.R. § 41.37(c)(1)(vii) 19 (2008). 20 This appeal turns on one issue: 21 Has the Appellant shown that the Examiner failed to 22 articulate reasoning with some rational underpinning sufficient 23 2 Although the Appeal Brief states that “the prior art does not objectively teach or suggest all of the claim elements” (App. Br. 9-10), the Appellant does not identify any claim element not disclosed by either Mukira, Peterson or Cross. Appeal 2008-4679 Application 10/746,388 4 to support the conclusion that the teachings of Mukira, in 1 combination with the teachings of Peterson and Cross, would 2 have suggested performing an HIP process after welding a 3 damaged region of a turbine without preheating the damaged 4 region rather than teaching away from performing a post-weld 5 HIP process? 6 7 FINDINGS OF FACT 8 The record supports the following findings of fact (“FF”) by a 9 preponderance of the evidence. 10 1. Mukira discloses repairing a turbine engine blade or bucket 11 using an electron beam welding process or a laser welding process 12 performed at room temperature to affix a solid solution strengthened 13 superalloy weld composition in a damaged portion of the blade. (Mukira, 14 col. 2, ll. 52-58 and col. 4, ll. 50-54.) 15 2. Mukira further discloses performing machining and coating 16 processes for further protection of the blade to complete the repair process 17 after the blade is welded. (Mukira, col. 2, ll. 64-67.) 18 3. Peterson discloses that one of ordinary skill in the art would 19 have known of the use of solid solution strengthened alloy weld 20 compositions to repair cracks in superalloy blades. (Peterson, col. 1, ll. 39-21 42.) 22 4. Peterson discloses that the weldability of blade superalloys is 23 limited by the tendency of the welds to form cracks. Peterson identifies two 24 distinct types of cracking to which such welds are susceptible. One type of 25 cracking identified by Peterson is hot cracking, which occurs typically 26 Appeal 2008-4679 Application 10/746,388 5 during welding in the form of microcracks beneath the surface of the 1 weldment. (Peterson, col. 1, ll. 27-34; see also id., col. 4, ll. 5-8.) 2 Peterson’s disclosure suggests that such cracking was known to occur in 3 repairs made using solid solution strengthened alloy weld compositions. 4 5. Peterson discloses that the use of low energy welding processes 5 such as electron beam welding processes and laser welding processes 6 reduces cracking. (Peterson, col. 2, ll. 6-9.) Peterson’s disclosure suggests 7 that the use of low energy welding processes does not eliminate the 8 susceptibility of turbine blade repair welds using solid solution strengthened 9 alloy weld compositions to cracking, however. 10 6. Peterson discloses performing HIP processes before and after a 11 low energy welding process to pre-condition a damaged blade for welding 12 and to seal the blade after welding. (Peterson, col. 2, ll. 28-34.) 13 7. Peterson teaches that the post-weld HIP process seals 14 microcracks below the surface of the weldment. (Peterson, col. 4, ll. 8-10.) 15 8. Mukira does not mention the possibility that cracks may form 16 while welding turbine engine blades using Mukira’s solid solution 17 strengthened superalloy weld composition. Neither does Mukira state that 18 cracking does not occur while welding turbine engine blades using Mukira’s 19 weld composition. 20 9. Mukira does not mention, much less criticize, performing an 21 HIP process after performing a low energy welding process to repair a 22 turbine engine blade using Mukira’s weld composition. 23 Appeal 2008-4679 Application 10/746,388 6 PRINCIPLES OF LAW 1 A claim is unpatentable for obviousness under 35 U.S.C. § 103(a) if 2 “the differences between the subject matter sought to be patented and the 3 prior art are such that the subject matter as a whole would have been obvious 4 at the time the invention was made to a person having ordinary skill in the 5 art to which said subject matter pertains.” In Graham v. John Deere Co., 6 383 U.S. 1 (1966), the Supreme Court set out factors to be considered in 7 determining whether claimed subject matter would have been obvious: 8 9 Under § 103, the scope and content of the prior art 10 are to be determined; differences between the prior 11 art and the claims at issue are to be ascertained; 12 and the level of ordinary skill in the pertinent art 13 resolved. Against this background the obviousness 14 or nonobviousness of the subject matter is 15 determined. 16 17 Id., 383 U.S. at 17. 18 The Appellant does not rely on any objective evidence of patentability 19 in this appeal. (See App. Br. 20). Therefore, the Appellant’s burden in this 20 appeal is to show that the Examiner has identified insufficient evidence to 21 support a conclusion of prima facie obviousness. In re Kahn, 441 F.3d 977, 22 985-86 (Fed. Cir. 2006) (citing In re Rouffet, 149 F.3d 1350, 1355 (Fed. Cir. 23 1998)). “[R]ejections on obviousness grounds cannot be sustained by mere 24 conclusory statements; instead, there must be some articulated reasoning 25 with some rational underpinning to support the legal conclusion of 26 obviousness.” Kahn, 441 F.3d at 988. 27 As a general rule, a reference which “teaches away” from the subject 28 matter of a claim does not support a prima facie case that the subject matter 29 Appeal 2008-4679 Application 10/746,388 7 would have been obvious. A reference teaches away from the subject matter 1 of a claim only if “a person of ordinary skill, upon reading the reference, 2 would be discouraged from following the path set out in the reference, or 3 would be led in a direction divergent from the path that was taken by the 4 applicant.” In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994). 5 6 ANALYSIS 7 The Appellant does not appear to contest that Mukira discloses 8 welding a damaged region of superalloy turbine blade without preheating3 9 the damaged region using a low energy welding process such as electron 10 beam welding or a laser welding. (See App Br. 9-10; Reply 2.) Peterson 11 would have suggested that repairing a superalloy turbine blade by 12 performing a low energy welding process using a solid solution strengthened 13 superalloy weld composition such as Mukira’s likely would produce 14 microcracks below the surface of the weldment. (FF 4 and 5.) The 15 Appellant points to nothing in Mukira which would have contradicted this 16 suggestion. (See FF 8.) Given the likelihood that a low energy welding 17 process using a solid solution strengthened superalloy weld composition 18 such as Mukira’s would leave microcracks below the surface of the 19 weldment, Peterson would have suggested performing a post-weld HIP 20 3 Mukira indicates that welding “without preheating” implies welding performed at room temperature. (Mukira, col. 1, ll. 37-42). The Appellant does not define the term “welding . . . without preheating” in the Specification or use the term in the Specification in a manner inconsistent with this interpretation. In any event, the Appellant does not appear to contest that Mukira discloses welding without preheating. (See App. Br. 8). Appeal 2008-4679 Application 10/746,388 8 process to seal any such microcracks and thereby improve the material 1 properties of the repair. (See FF 6 and 7.) 2 Mukira is merely silent concerning the performance of a post-weld 3 HIP process to seal any microcracks left by the low energy welding process. 4 (FF 9.) Mukira does mention performing certain post-weld process, such as 5 additional machining as well as coating processes. (see FF 2.) Even if, as 6 the Appellant argues (see Reply Br. 2), Mukira’s silence indicates that the 7 author of Mukira did not believe that a post-weld HIP process is needed, 8 Mukira’s silence concerning the use of post-weld HIP processes while 9 describing the use of other post-weld processes does not imply any criticism 10 of the use of a post-weld HIP process. Likewise, Mukira’s silence does not 11 imply that a repair to a superalloy turbine blade made by applying a post-12 weld HIP process to a blade welded using Mukira’s weld composition would 13 be inoperative for its intended purpose. Mukira’s silence, even when 14 considered in the context of Mukira’s disclosure as a whole, is not a teaching 15 away from the use of a post-weld HIP process to seal any microcracks left 16 by the welding process disclosed by Mukira. Cf. DyStar Textilfarben GmbH 17 v. C.H. Patrick Co., 464 F.3d 1356, 1364 (Fed. Cir. 2006)(“We will not read 18 into a reference a teaching away from a process where no such language 19 exists.”). 20 21 CONCLUSIONS 22 The Appellant has not shown that the Examiner failed to articulate 23 reasoning with some rational underpinning sufficient to support the 24 conclusion that the teachings of Mukira, in combination with the teachings 25 of Peterson and Cross, would have suggested performing an HIP process 26 Appeal 2008-4679 Application 10/746,388 9 after welding a damaged region of a turbine without preheating the damaged 1 region rather than teaching away from performing a post-weld HIP process. 2 Therefore, the Appellant has not shown that the Examiner erred in rejecting 3 claims 1-4, 8, 10-12, 14, 17, 19-22 and 25 under 35 U.S.C. § 103(a) as being 4 unpatentable over Mukira, Peterson and Cross. 5 6 DECISION 7 The Examiner’s rejection of claims 1-4, 8, 10-12, 14, 17, 19-22 and 8 25 is AFFIRMED. 9 No time period for taking any subsequent action in connection with 10 this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv) (2007). 11 12 13 AFFIRMED 14 15 16 17 18 19 20 21 LV: 22 23 HONEYWELL INTERNATIONAL INC. 24 101 COLUMBIA ROAD 25 P O BOX 2245 26 MORRISTOWN, NJ 07962-2245 27 Copy with citationCopy as parenthetical citation