Prosecution Insights
Last updated: October 01, 2026
Application No. 18/862,324

MAINTENANCE METHOD FOR GAS TURBINES

Non-Final OA §102§103
Filed
Nov 01, 2024
Priority
May 10, 2022 — JP 2022-077565 +1 more
Examiner
DELRUE, BRIAN CHRISTOPHER
Art Unit
3745
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Mitsubishi Heavy Industries Ltd.
OA Round
1 (Non-Final)
84%
Grant Probability
Favorable
1-2
OA Rounds
4m
Est. Remaining
99%
With Interview

Examiner Intelligence

Grants 84% — above average
84%
Career Allowance Rate
369 granted / 438 resolved
+14.2% vs TC avg
Strong +22% interview lift
Without
With
+21.7%
Interview Lift
resolved cases with interview
Typical timeline
2y 3m
Avg Prosecution
27 currently pending
Career history
475
Total Applications
across all art units

Statute-Specific Performance

§101
0.9%
-39.1% vs TC avg
§103
40.8%
+0.8% vs TC avg
§102
30.5%
-9.5% vs TC avg
§112
25.3%
-14.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 438 resolved cases

Office Action

§102 §103
DETAILED ACTION Status of Claims This action is in reply to the application filed on 01 November 2024. Claims 1-4 are canceled by the Applicant. Claims 5-15 are newly presented by the Applicant. Claims 5-15 are currently pending. Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Information Disclosure Statement The information disclosure statement(s) (IDS) submitted was/were considered by the examiner. It is noted, the cited Non-Patent Literature (NPL) “line number CC” has been lined through since there was no English translation provided. The English translation of the aforementioned NPL has been cited by the Examiner in the PTO-892. Claim Interpretation The following is a quotation of 35 U.S.C. 112(f): (f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof. The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph: An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof. The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked. As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph: (A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function; (B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and (C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function. Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function. Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function. Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Examiner note: no 112(f) invocations have been identified by the Office. Claim Objections Claim 5 objected to because of the following informalities: The claim language, "the variable vane constituting each row" lacks sufficient antecedent basis for the limitation in the claim. As best understood, for purposes of examination, the claim language is interpreted to instead be, "a [[the]] variable vane of the variable vanes constituting each row." Appropriate correction is required. Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention. (a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Claim(s) 5 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Emmet et al (US 20160061117), hereafter referred to as Emmet. Regarding Claim 5, Emmet discloses the following: A gas turbine (10) comprising: an inlet guide vane (33) disposed at an inlet of a compressor that is rotatably driven around an axis, and a first ring (50; FIG. 3) connected to the inlet guide vane (33); a plurality of rows of variable vanes (37, 41) disposed on a downstream side with respect to the inlet guide vane (33) in a direction of the axis, and a plurality of second rings (50; FIG. 3) corresponding to each of the plurality of rows (37, 41) and connected to the variable vane constituting each row (37, 41); and a first actuator (64 or alternatively 164) rotating the first ring (50; FIG. 3) in a circumferential direction, and a second actuator (65 or alternatively 165) rotating the plurality of second rings (50; FIG. 3) in the circumferential direction, wherein the first actuator (64 or alternatively 164) and the second actuator (65 or alternatively 165) have the same specifications (64 and 65 in FIG. 3 appear to be identical; 164 and 165 in FIG. 7 appear to be identical). Claim Rejections - 35 USC § 103 The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. Claims 6-15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Emmet et al (US 20160061117), hereafter referred to as Emmet, as applied to claim 5 above, in further view of Non-Patent Literature “Maintenance and management of gas turbine equipment in combined cycle power generation,” Authored by Izumi Fujii, hereafter referred to as Fujii. Regarding Claim 6, Emmet discloses the following: A maintenance method for the gas turbine (10) according to Claim 5 comprising: Emmet does not explicitly disclose the following: a step of detaching the first actuator and attaching a third actuator at a first inspection time; a step of detaching the second actuator and attaching the first actuator, which has completed maintenance, at a second inspection time; and a step of detaching the third actuator and attaching the second actuator, which has completed maintenance, at a third inspection time. However Fujii teaches the following: a step of detaching the first actuator (A; FIG. 3) and attaching a third actuator (E; FIG. 3) at a first inspection time (end of year 1; Original, FIG. 3); a step of detaching the second actuator (B; FIG. 3) and attaching the first actuator (A; FIG. 3), which has completed maintenance, at a second inspection time (within 2 years when A replaces B; Original, FIG. 3); and a step of detaching the third actuator (E; FIG. 3) and attaching the second actuator (B; FIG. 3), which has completed maintenance, at a third inspection time (end of 2 years when B replaces E; Original, FIG. 3). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the gas turbine engine comprising a first and second actuator, as disclosed by Emmet, with the method of maintaining turbine engine components, as disclosed by Fujii, with the reasonable expectation of successfully extending the lifespan of gas turbine components, thereby reducing gas turbine maintenance costs (see for example Fujii section 22, last paragraph). Regarding Claim 7, Emmet discloses the following: A maintenance method for the gas turbine (10) according to Claim 5 comprising: Emmet does not explicitly disclose the following: a step of detaching the second actuator and attaching a third actuator at a first inspection time; a step of detaching the first actuator and attaching the second actuator, which has completed maintenance, at a second inspection time; and a step of detaching the third actuator and attaching the first actuator, which has completed maintenance, at a third inspection time. However Fujii teaches the following: a step of detaching the second actuator (A; FIG. 3) and attaching a third actuator (E; FIG. 3) at a first inspection time (end of year 1; Original, FIG. 3); a step of detaching the first actuator (B; FIG. 3) and attaching the second actuator (A; FIG. 3), which has completed maintenance, at a second inspection time (within 2 years when A replaces B; Original, FIG. 3); and a step of detaching the third actuator (E; FIG. 3) and attaching the first actuator (B; FIG. 3), which has completed maintenance, at a third inspection time (end of 2 years when B replaces E; Original, FIG. 3). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the gas turbine engine comprising a first and second actuator, as disclosed by Emmet, with the method of maintaining turbine engine components, as disclosed by Fujii, with the reasonable expectation of successfully extending the lifespan of gas turbine components, thereby reducing gas turbine maintenance costs (see for example Fujii section 22, last paragraph). Regarding Claim 8, Emmet as modified by Fujii discloses the following: The maintenance method for the gas turbine (10) according to claim 6, Fujii continues to teach the following: wherein the steps are sequentially and continuously repeated (as seen in FIG. 3). Regarding Claim 9, Emmet as modified by Fujii discloses the following: The maintenance method for the gas turbine (10) according to claim 7, Fujii continues to teach the following: wherein the steps are sequentially and continuously repeated (as seen in FIG. 3). Regarding Claim 10, Emmet as modified by Fujii discloses the following: The maintenance method for the gas turbine (10) according to claim 6, Fujii continues to teach the following: a step of performing maintenance on the first actuator (A; FIG. 3) which is detached (synonymous with factor; FIG. 3); and a step of performing maintenance on the second actuator (B; FIG. 3) which is detached (synonymous with factor; FIG. 3) (as seen in FIG. 3). Regarding Claim 11, Emmet as modified by Fujii discloses the following: The maintenance method for the gas turbine (10) according to claim 7, Fujii continues to teach the following: a step of performing maintenance on the first actuator (A; FIG. 3) which is detached (synonymous with factor; FIG. 3); and a step of performing maintenance on the second actuator (B; FIG. 3) which is detached (synonymous with factor; FIG. 3). Regarding Claim 12, Emmet as modified by Fujii discloses the following: The maintenance method for the gas turbine (10) according to claim 6, Fujii continues to teach the following: wherein the first actuator (A; FIG. 3), the second actuator (B; FIG. 3), and the third actuator (E; FIG. 3) are sequentially used only in the same gas turbine (units 1 and 2 in FIG. 3 as applied to Emmet). Regarding Claim 13, Emmet as modified by Fujii discloses the following: The maintenance method for the gas turbine (10) according to claim 7, Fujii continues to teach the following: wherein the first actuator (B; FIG. 3), the second actuator (A; FIG. 3), and the third actuator (E; FIG. 3) are sequentially used only in the same gas turbine (units 1 and 2 in FIG. 3 as applied to Emmet). Regarding Claim 14, Emmet as modified by Fujii discloses the following: The maintenance method for the gas turbine (10) according to claim 6, Fujii continues to teach the following: wherein the third actuator (E; FIG. 3) has the same specifications (as evidenced by the parts A, B, and E being interchanged; FIG. 3) as the first actuator (A; FIG. 3) and the second actuator (B; FIG. 3). Regarding Claim 15, Emmet as modified by Fujii discloses the following: The maintenance method for the gas turbine (10) according to claim 7, Fujii continues to teach the following: wherein the third actuator (E; FIG. 3) has the same specifications (as evidenced by the parts A, B, and E being interchanged; FIG. 3) as the first actuator (B; FIG. 3) and the second actuator (A; FIG. 3). Conclusion See form No. 892 for other references pertinent to the application that may not have been cited within the Office Action. For references which show gas turbine and/or maintenance arrangements see Page 1. Any inquiry concerning this communication or earlier communications from the examiner should be directed to BRIAN C DELRUE whose telephone number is (313)446-6567. The examiner can normally be reached Monday - Friday; 9:00 AM - 5:00 PM (Eastern). Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Nathaniel E. Wiehe can be reached at (571) 272-8648. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /BRIAN CHRISTOPHER DELRUE/ Primary Examiner, Art Unit 3745
Read full office action

Prosecution Timeline

Nov 01, 2024
Application Filed
Jun 18, 2026
Non-Final Rejection mailed — §102, §103
Sep 10, 2026
Applicant Interview (Telephonic)

Precedent Cases

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
84%
Grant Probability
99%
With Interview (+21.7%)
2y 3m (~4m remaining)
Median Time to Grant
Low
PTA Risk
Based on 438 resolved cases by this examiner. Grant probability derived from career allowance rate.

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