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 .
Election/Restrictions
Claims 7-8, 17-18 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 3/05/2026.
Applicant’s election without traverse of Species A in the reply filed on 3/05/2026 is acknowledged.
Claim Interpretation
Regarding claim 19, the recitation “diverting… when the temperature… or recirculating… when the temperature…” is a contingent limitation. The claim does not require the following conditions if the conditions are not satisfied. Therefore, because the determination is contingent on an event that may not occur, the claimed method can be carried out without performing the diverting/recirculating. (see MPEP 2111.04 II). Should Applicant wish to obviate this interpretation, it is suggested the conditional recitations of “when” be replaced with “in response to” or the like. It is noted this interpretation does not apply to the controller recitations of the same in claims 2 and 12.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-6, 9-16, 19-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 1, the recitation “one or more valve in fluid communication with the recirculation conduit and the bypass conduit, the one or more valve operable to selectively allow the fluid to flow in one of the recirculation conduit and the bypass conduit while limiting the fluid from flowing in the other of the recirculation conduit and the bypass conduit” is unclear. In the case of more than one valves, the claim language implies all of the valves are in fluid communication with and limits/allows the flow of both the recirculation conduit and bypass conduit, whereas the disclosure does not provide for such a configuration. As seen in Fig. 2, no single or multiple valves are in fluid communication with and allows/limits the flow of both the bypass conduit and the recirculation conduit, but rather, one valve is in fluid communication with and allows/limits the flow of the bypass conduit and another valve is in fluid communication with and allows/limits the flow of the the recirculation conduit (see also MPEP 2173.03, which requires consistency of claims with the disclosure). Claims 11 and 19 are similarly rejected.
Regarding claim 1, the recitation “a recirculation conduit fluidly connecting the outlet conduit to the inlet conduit while bypassing the heat exchanger” is unclear. By definition “recirculation,” and explicitly stated in the claim, the recirculation conduit feeds fluid to the inlet of the heat exchanger, and thus it is unclear how it can also “bypass” the heat exchanger. This also contradicts the disclosure, in which the recirculation conduit does not bypass the heat exchanger, but rather, feeds flow directly to the inlet. Claim 20 is similarly rejected for its recitation of “a recirculation conduit in a bypass configuration.”
Claim(s) 2-6, 9-10, 12-16, and 20 is/are rejected for their dependency from the claim(s) above.
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.
Claim(s) 19 is/are rejected under 35 U.S.C. 102 (a) (1) as being anticipated by Le Bot (US20210190421A1).
Regarding claim 19, Le Bot discloses a method of mitigating temperature variations at an outlet of a heat exchanger (Fig. 1), comprising: transferring heat from a first fluid to a second fluid via a heat exchanger (vaporizer, see also ¶[0022]); determining that a temperature of the second fluid at an outlet of the heat exchanger is outside a predetermined temperature range (via temperature indicator 50, see also ¶[0024-0025]); and diverting a portion of the second fluid flowing towards the heat exchanger to bypass the heat exchanger when the temperature is above the predetermined temperature range (via bypass valve 30 & ¶[0024]).
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.
Claim(s) 1, 9-11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Alecu (US20160281656A1) in view of Gomez (US20250042568A1) and Keeler (US20250198343A1).
Regarding claim 1/11, Alecu teaches an aircraft engine (Fig. 2) comprising: a thermal engine (engine 10) having an outlet outputting exhaust gases; a heat exchanger (FOHE 32) having a first conduit fluidly connected to a source (fuel tank 22) of a fluid being at a lower temperature than the exhaust gases, an inlet conduit (fuel line 23 upstream of 32) fluidly connecting the source of the fluid to an inlet of the first conduit of the heat exchanger; an outlet conduit (fuel line 23 downstream of 32) fluidly connected to an outlet of the first conduit of the heat exchanger; a component (turbine section 18) fluidly connected to the outlet conduit; a recirculation conduit (motive flow 26) fluidly connecting the outlet conduit to the inlet conduit while bypassing the heat exchanger; one or more valve in fluid communication with the recirculation conduit, the one or more valve operable to selectively allow the fluid to flow in the recirculation conduit; and a flow inducer (ejector pump 24) in fluid communication with the recirculation conduit for inducing a flow from the outlet conduit to the inlet conduit via the recirculation conduit.
Alecu does not teach a second conduit fluidly connected to the outlet of the thermal engine and in heat exchange relationship with the first conduit, the second conduit receiving exhaust gases generated by aircraft engine, however, teaches wherein other types of fuel heaters may be used (¶[0010]).
Gomez teaches a second conduit (6.1) fluidly connected to the outlet of the thermal engine and in heat exchange (via heat exchanger 6) relationship with the first conduit (fuel conduit 3), the second conduit receiving exhaust gases generated by aircraft engine.
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified Alecu to include the exhaust gas heat exchanger of Gomez, in order to recover heat from the exhaust gas of the engine (¶[0013]).
Alecu does not teach a bypass conduit fluidly connecting the inlet conduit to the outlet conduit while bypassing the heat exchanger; one or more valve in fluid communication with the recirculation conduit and the bypass conduit, the one or more valve operable to selectively allow the fluid to flow in one of the recirculation conduit and the bypass conduit while limiting the fluid from flowing in the other of the recirculation conduit and the bypass conduit; and a flow inducer in fluid communication with the recirculation conduit for inducing a flow from the outlet conduit to the inlet conduit via the recirculation conduit, the bypass conduit and the recirculation conduit extending in parallel to the first conduit of the heat exchanger.
Keeler teaches a bypass conduit (see bypass conduit from bypass valve 1201; Fig. 19 & ¶[0407]) fluidly connecting the inlet conduit to the outlet conduit while bypassing the heat exchanger (heat exchanger 1220); one or more valve (valves 1201 & 1202) in fluid communication with the recirculation conduit (recirculation pipe 1206) and the bypass conduit, the one or more valve operable to selectively allow the fluid to flow in one of the recirculation conduit and the bypass conduit while limiting the fluid from flowing in the other of the recirculation conduit and the bypass conduit, the bypass conduit and the recirculation conduit extending in parallel to the first conduit of the heat exchanger.
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified Alecu to include the bypass conduit configuration, in order to control the heat transfer ratio of the heat exchanger (¶[0418]).
Regarding claim 9, Alecu as modified teaches the limitations of claim 1, and Gomez further teaches the source of the fluid is a source of liquid hydrogen, which is a well known fuel for aircraft gas turbine engines (¶[0011]). Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified Alecu to use liquid hydrogen as the fuel source, as it has been held obvious to provide a simple substitution (see MPEP 2143).
Regarding claim 10, Alecu as modified teaches the limitations of claim 1, and Alecu further teaches the component is an expansion turbine (18).
Allowable Subject Matter
Claims 2-6, 12-16, 20 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ERIC S RUPPERT whose telephone number is (571)272-9911. The examiner can normally be reached Monday - Friday 8 am - 4 pm.
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/ERIC S RUPPERT/Primary Examiner, Art Unit 3763