DETAILED ACTION
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 .
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Response to Amendment
This Office action is responsive to the amendment filed 26 May 2026. Claims 1-11 are pending and are examined.
Claim Rejections - 35 USC § 103
Claims 1-7, 10 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Fonseca (US 2017/0292412).
Regarding claim 1, Fonseca teaches an exhaust system 10 for a turbine engine 14 comprising a nozzle 12 at least partly delimiting a gas exhaust path, characterised in that it comprises a heat exchanger 52 comprising at least one distributor 70, at least one manifold 72 and ducts configured for the flow of a heat-transfer fluid 24 in said ducts 54 between the distributor and the manifold (¶28, a plurality of passageways 54 are created through which a fluid 24 can flow), the heat exchanger being configured to carry out heat exchanges between the gas exhaust path and the ducts (¶28), and the heat exchanger being positioned on the nozzle (¶28, heat exchanger jackets are sandwiched between an inner skin 48 and outer skin 48 of exhaust nozzle 12).
Fonseca doesn’t teach the ducts being partially formed from a surface of the nozzle.
Fonseca teaches the heat exchanger 52 is formed from two sheets of welded together between the inner skin 48 and outer skin 50 of the exhaust nozzle (¶28). The heat exchangers can both be formed from Inconel (¶28, ¶51). The inner and outer skin of the nozzle can be made of Inconel (¶42). It is noted that making a part integral, i.e., integrating the skin of the nozzle with the heat exchanger, as it is disclosed and claimed in the instant application, was an obvious extension of prior art teachings, In re Larson, 340 F.2d 965, 968, 144 USPQ 347, 349 (CCPA 1965) (MPEP 2144.04 V B.). Further, when the Inconel heat exchanger is mounted to the Inconel skin of the nozzle, the heat exchanger becomes part of the exhaust nozzle and thus, the ducts are partially formed from a surface of the nozzle as claimed.
Regarding claim 2, Fonseca teaches the invention as claimed and discussed above and Fonseca further teaches the nozzle comprises an annular outer part and a central body (Fig. 2), the heat exchanger being positioned on the outer part (Figs. 5, 7) and/or on the central body (Fig. 2).
Regarding claim 3, Fonseca teaches the invention as claimed and discussed above and Fonseca further teaches the outer part of the nozzle comprises one or more annular sectors (Fig. 7 shows two annular sectors.
Regarding claim 4, Fonseca teaches the invention as claimed and discussed above and Fonseca further teaches the ducts are positioned outside or inside the gas exhaust path (Ducts are positioned outside gas path in Fig. 7, i.e., sandwiched within the nozzle interior.).
Regarding claim 5, Fonseca teaches the invention as claimed and discussed above and Fonseca further teaches the ducts extend longitudinally parallel to a longitudinal axis of the exhaust system, or transversely to the longitudinal axis (Ducts 52 in Fig. 5 satisfy one of these conditions).
Regarding claim 6, Fonseca teaches the invention as claimed and discussed above and Fonseca further teaches made of a material comprising a titanium alloy and/or a nickel alloy (Inconel is a nickel alloy).
Regarding claim 7, Fonseca teaches the invention as claimed and discussed above and Fonseca further teaches the heat exchanger is configured to carry out heat exchanges between exhaust gases leaving through the gas exhaust path and a heat-transfer fluid flowing in the ducts, said heat-transfer fluid comprising air and/or water vapour and/or water and/or fuel and/or oil and/or supercritical CO2 and/or liquid or gaseous hydrogen (steam generator is taught ¶13. Other fluids may be used but water vapour is not excluded).
Regarding claim 10, Fonseca teaches the invention as claimed and discussed above and Fonseca further teaches a thermal management system for heating air or fuel in a turbine engine (¶66, energy from the system is used in compressors to heat air).
Regarding claim 11, Fonseca teaches the invention as claimed and discussed above and Fonseca further teaches an aircraft comprising the exhaust system of claim 1 (¶3, system is for aircraft).
Claims 8 and 9 are rejected under 35 U.S.C. 103 as being unpatentable over Muldoon (US 2022/0381185) in view of Fonseca (US 2017/0292412).
Regarding claim 8, Muldoon teaches a turbine engine (200, Fig. 2) comprising a compressor 206 and a combustion chamber 210, characterised in that it comprises an exhaust system 232, the heat exchanger being configured to heat fuel at the inlet of the combustion chamber (Fuel is received from tank 224, which passes through heat exchanger 232 and heated, is expanded in a turbine 234 and enters inlet of combustor. Thus, the fuel is heated in the inlet of the combustor).
Muldoon doesn’t teach the exhaust system of claim 1.
As discussed above for claim 1, Fonseca teaches the exhaust system of claim 1. In both Muldoon and Fonseca, the exhaust heat exchanger is located on the exhaust nozzle and used to heat a fluid and expand it through a turbine to generate energy. Muldoon doesn’t teach details of the exhaust system heat exchanger.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to make the turbine engine of Muldoon have the exhaust system of claim 1, as taught by Fonseca, in order to allow the hydrogen to be expanded and generate energy using the heat from the exhaust nozzle.
Regarding claim 9, Muldoon in view of Fonseca teaches the invention as discussed above and Muldoon further teaches an aircraft with the engine (Fig. 4).
Response to Arguments
Applicant's arguments filed 26 May 2026 have been fully considered but they are not persuasive. In Applicant’s disclosure, a sheet with indentations is welded to a surface. The surface is part of an exhaust nozzle. The ducts are closed when the indentations are joined to the surface. Claim 1 refers to this structure with the limitation “the ducts being partially formed from a surface of the nozzle.”
In Fonseca, the nozzle comprises an inner sheet 48, an outer sheet 50 and heat exchanger 52 (Fig. 7, ¶28). Ducts can be formed in the heat exchanger 52 using two sheets of Inconel. (¶28, ¶51, specifically teaches the two sheets of the heat exchanger can be Inconel). The two sheets of the heat exchanger 52 are sandwiched between the inner wall/skin 48 and outer wall/skin of the 50 of the exhaust nozzle shroud (¶46). These walls, 48 and 50, are also made of Inconel (¶46).
Thus, Fonseca teaches a stack-up of at least four Inconel sheets that form an exhaust nozzle. The Inconel sheets that form the heat exchanger 52 are sandwiched together to form ducts. The Inconel sheets of the heat exchanger provide a portion of the interior structure of the nozzle and are also surfaces of the exhaust nozzle. For this reason, the ducts in Fonseca are partially formed from a surface of the nozzle because they are also part of the structure of the nozzle.
One could assemble the nozzle of Fonseca by first joining a first sheet of the heat exchanger 52 to the sheet of the inner wall 48. This structure of the first sheet and the inner wall can be designated a first portion of the exhaust nozzle. Then, a second sheet the heat exchanger 52 can be joined to the first portion of the exhaust nozzle to form a stack-up of three sheets. Thus, assembled this way, the ducts are partially formed from a surface of nozzle, as claimed.
The above example is how Applicants device is formed. Applicant is arguing first sheet is part of the heat exchanger and only the inner wall is part of the nozzle. Examiner’s position is that this is an arbitrary distinction and the first sheet and the inner wall can be considered part of the nozzle. Then, when the second sheet is joined to the first sheet, the ducts are partially formed from a surface of the nozzle. The order of assembling the sheets is an obvious variation.
Applicant argues that the heat exchangers in Fonseca are distinct and separate from the exhaust nozzle while ignoring the fact that heat exchangers are also an interior structural component of the exhaust nozzle stack-up as taught in Fonseca. Applicant further argues the Fonseca teaches heat exchangers are formed from different materials than the nozzle walls, which makes them distinct. This argument is incorrect as Fonseca a specifically teaches the sheets forming the nozzle walls 48, 50 and sheets forming the heat exchangers 52 can all be of the same material. For these reasons, Applicant’s arguments are not found to be persuasive.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DAVID OLYNICK whose telephone number is (571)272-2355. The examiner can normally be reached M-F: 7:30 am-5 pm (ET).
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Phuttiwat Wongwian can be reached at (571) 270-5426. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/DAVID P. OLYNICK/Primary Examiner, Art Unit 3741
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