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 .
This is the first Office action responsive to application 19364678 filed 10/21/2025. Claims 1-20 are pending.
Election/Restrictions
Applicant's election with traverse of the invention of Group II, Species B, and Sub-Species 1 in the reply filed on 5/26/2026 is acknowledged. The traversal is on the ground(s) that there would be no serious search burden. This is not found persuasive because the method would require substantial keyword searches that diverge significantly from the search required for the apparatus in order to find the specific operating steps (e.g. temperature ranges of fuel under particular operating conditions). See MPEP 808.02(C).
The requirement is still deemed proper and is therefore made FINAL.
Claim Objections
Claim 14 is objected to because of the following informalities:
The recitation “the heat exchangers” (l. 6) is believed to be in error for - - the two fuel-oil heat exchangers - -.
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.
Claims 14-20 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Weiner 20160024964.
Regarding Independent Claim 14, Weiner teaches a gas turbine engine (Fig. 1) for an aircraft, the gas turbine engine comprising:
a combustor (56) arranged to combust a fuel; and
a fuel management system (Fig. 2) arranged to provide the fuel to the combustor (para. [0028]), wherein the fuel management system comprises:
two fuel-oil heat exchangers (ENGINE FOC and HIGH PRESSURE FOC) arranged to have oil (from OIL TANK AOC) and the fuel (see FUEL METERING element inline with heat exchangers) flow therethrough, the heat exchangers arranged to transfer heat between the oil and the fuel and comprising a primary fuel-oil heat exchanger (ENGINE FOC) and a secondary fuel-oil heat exchanger (HIGH PRESSURE FOC); and
a fuel pump (see Fig. 1: Annotated Fig. 2 from Weiner below, annotated fuel pump) arranged to deliver the fuel to the combustor, wherein the fuel pump is located between the two fuel-oil heat exchangers (between ENGINE FOC AND HIGH PRESSURE FOC).
The recitation “wherein the fuel management system is arranged to raise the fuel temperature to at least 135°C on entry to the combustor at cruise conditions” is a functional limitation of the recited heat exchangers and pump. Weiner’s fuel management system is structured identically to the claimed fuel management system, using the same gas turbine engine fluids passing through the same components in the same arrangement, and is thus found capable of operating in the claimed manner. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01 I.
As Weiner teaches all the structural limitations of the claim, the functional recitation in the instant claim does not differentiate the claimed apparatus from the prior art apparatus, and therefore the instant claim is anticipated by Weiner.
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Figure 1: Annotated Fig. 2 from Weiner
Regarding Dependent Claim 15, the recitation “the fuel management system is arranged to raise the fuel temperature to between 135°C and 170°C on entry to the combustor at cruise conditions” is a functional limitation of the recited heat exchangers and pump. Weiner’s fuel management system is structured identically to the claimed fuel management system, using the same gas turbine engine fluids passing through the same components in the same arrangement, and is thus found capable of operating in the claimed manner. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01 I.
Regarding Dependent Claim 16, the recitation “the fuel management system is arranged to raise the fuel temperature to between 150°C and 170°C on entry to the combustor at cruise conditions” is a functional limitation of the recited heat exchangers and pump. Weiner’s fuel management system is structured identically to the claimed fuel management system, using the same gas turbine engine fluids passing through the same components in the same arrangement, and is thus found capable of operating in the claimed manner. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01 I.
Regarding Dependent Claim 17, Weiner further teaches the fuel management system further comprises: a recirculation valve located downstream of the primary fuel-oil heat exchanger, the recirculation valve arranged to allow a controlled amount of fuel which has passed through the primary fuel-oil heat exchanger to be returned to an inlet of the primary fuel-oil heat exchanger (BYPASS DIRECTION CONTROL VALVE permits controlled amount of fuel which has passed through ENGINE FOC to be returned via the annotated recirculation line, see Fig. 1: Annotated Fig. 2 from Weiner above, to the inlet of ENGINE FOC).
Regarding Dependent Claim 18, Weiner further teaches the secondary fuel-oil heat exchanger is a servo fuel-oil heat exchanger (the label “servo” does not convey additional structure to the secondary fuel-oil heat exchanger, it is merely a label indicating an intended use, thus the term “servo fuel-oil heat exchanger” does not distinguish over Weiner’s HIGH PRESSURE FOC, which is capable of provide heated fuel to be used for servos downstream, but this is not required in the claim).
Regarding Dependent Claim 19, the recitation “a ratio of heat transfer from the oil to the fuel for the primary and secondary fuel-oil heat exchangers is between 70:30 and 90:10” is a functional limitation of the recited heat exchangers. Weiner’s fuel management system is structured identically to the claimed fuel management system, using the same gas turbine engine fluids passing through the same components in the same arrangement, and is thus found capable of operating in the claimed manner. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01 I.
Regarding Dependent Claim 20, Weiner further teaches the fuel management system is arranged such that the fuel flows through the primary fuel-oil heat exchanger prior to flowing through the secondary fuel-oil heat exchanger (fuel passes through ENGINE FOC prior to flowing through HIGH PRESSURE FOC) whereas the oil flows through the secondary fuel-oil heat exchanger prior to flowing through the primary fuel-oil heat exchanger (oil flows through HIGH PRESSURE FOC prior to flowing through ENGINE FOC).
Examiner Comment
While not relied upon in the rejections above, Schwarz 20070264133 anticipates at least claims 14-16 & 19-20 (fuel-oil heat exchangers 35, 39, pump 37 between them, combustor at 40) and specifically teaches high temperatures of fuel provided to the combustor (maximum of about 300°F; para. [0029]).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SCOTT J WALTHOUR whose telephone number is (571)272-4999. The examiner can normally be reached Monday-Friday, 10 a.m.-6 p.m. Eastern.
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/SCOTT J WALTHOUR/Primary Examiner, Art Unit 3741
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