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Claims 15-27 withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Group 2, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 7/28/2026.
Applicant’s election of Group 1 in the reply filed on 7/28/2026is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)).
Claim Objections
Claim 1, line 3 is objected to because of the following informalities: “supply fuel to a jet engine” should be - -supply the fuel to the jet engine- -. Appropriate correction is required.
Claim 2, line 2 is objected to because of the following informalities: “which fuel” should be - -which the fuel- -. Appropriate correction is required.
Claim 3, line 3 is objected to because of the following informalities: “the cooled pressurized air” should be - - the cooled and pressurized air - -. Appropriate correction is required.
Claim 13, line 7 is objected to because of the following informalities: “the work” should be - - work - -. Appropriate correction is required.
Claim 14, line is objected to because of the following informalities: “An aircraft” should be - -The aircraft- -. Appropriate correction is required.
Claim 14, line 4 is objected to because of the following informalities: “at least one jet engine” should be - -at least one of the jet engine- -. 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.
Claim(s) 1, 3-4, 7-11, 13 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Wolf (US 3733826).
Regarding claim 1, Wolf discloses an apparatus (Figure) for warming fuel (The fuel in Figure; fuel tank) prior to combustion in a jet engine (Figure; combustor and nozzles) of an aircraft (The aircraft having the jet engine. Figure is part of the aircraft. Column 1, lines 55-58, Column 2-3, lines 60-4 describe thrust, so that the invention relates to an aircraft) and supplying cooled bleed air (The air from Figure; air compressor to the combustor and nozzles) to the aircraft, the apparatus comprising:
a fuel flow path (The flow path from Figure: fuel tank to combustor and then nozzles) configured to supply the fuel to the jet engine for combustion (Functional Language, the fuel flow path supplies the fuel to the jet engine for combustion);
an air flow path (The flow path of the air from Figure; air inlet to combustor and then nozzles) including an inlet air conduit (The conduit formed by Figure; air inlet and the passage for air in second heat exchanger stage) configured to receive external freestream ram air (The ram air in Column 1, lines 8-14. Functional Language, the inlet air conduit receives external freestream ram air); and
an inlet air heat exchanger (Figure; second heat exchanger stage) configured to transfer heat (The heat from the air to the fuel. Column 2, lines 40-46) from the inlet air conduit to the fuel in a gaseous state (Column 2, lines 9-18) in the fuel flow path prior to supply of the fuel to the jet engine (Functional Language, the inlet air heat exchanger transfers heat to the fuel in a gaseous state in the fuel flow path prior to supply of the fuel to the jet engine) ,
wherein the inlet air conduit is a first air conduit (The inlet conduit is a first air conduit) and the air flow path includes a second air conduit (The conduit from Figure; second heat exchanger to combustor and then nozzles) that directs cooled air after the inlet air heat exchanger to the aircraft (Functional Language, the second air conduit directs cooled air after the inlet air heat exchanger to the aircraft).
Regarding claim 3, Wolf discloses the invention as claimed.
Wolf further discloses at least one compressor (Figure; air compressor) that compresses the inlet air following heat transfer in the inlet air heat exchanger to obtain cooled and pressurized air (The cooled and pressurized air from Figure; air compressor), wherein the air flow path is configured to supply the cooled and pressurized air to the aircraft (The air flow path supplies the cooled pressurized air to the aircraft).
Regarding claim 4, Wolf discloses the invention as claimed.
Wolf further discloses wherein:
the at least one compressor produces at least two pressurized air supplies of differing pressures (The supplies of air exiting Figure; air compressor and the air within the compressor which is supplied to heat exchanger in the air compressor. These two supplies have different pressures because one is fully compressed by the air compressor while the other is only partially compressed by the air compressor); and
the air flow path is configured to provide the at least two pressurized air supplies to the jet engine (Functional language, the at least two pressurized air supplies are provided to the jet engine).
Regarding claim 7, Wolf discloses the invention as claimed.
Wolf further discloses at least one expander (Figure; first turbine stage) driven by expansion of the fuel (The at least one expander is driven by expansion of fuel); and
a power shaft (The shaft of Figure; first turbine stage) coupled to the expander.
Regarding claim 8, Wolf discloses the invention as claimed.
Wolf further discloses a fuel pump (Figure; pump) powered based on motion of the power shaft to pump the fuel into the fuel flow path (Functional language, the fuel pump is powered based on motion of the power shaft to pump the fuel into the fuel flow path)
Regarding claim 9, Wolf discloses the invention as claimed.
Wolf further discloses an auxiliary powered device (Figure; second turbine stage. A second stage turbine by-pass valve makes this an auxiliary device) powered based on motion of the power shaft (Functional language, Figure; second turbine stage is powered based on motion of the power shaft).
Regarding claim 10, Wolf discloses the invention as claimed.
Wolf further discloses wherein:
the at least one expander includes a first expander (Figure; first turbine stage is a first expander);
the power shaft is a first shaft (The power shaft is a first shaft); and
the apparatus further includes
a second shaft (The shaft of Figure; second turbine stage):
a second expander (Figure; second turbine stage) driven by expansion of the fuel in the fuel flow path (Functional Language, the second expander is driven by expansion of fuel in the fuel flow path), wherein the second expander is coupled to and drives the second shaft (Functional language, the second expander is coupled to and drives the second shaft); and
a valve (Figure; second stage turbine by-pass valve) controlling a fraction of the fuel passing through the second expander (The fraction of the fuel passing through the second expander. Functional Language, Column 4, lines 3-10).
Regarding claim 11, Wolf discloses the invention as claimed.
Wolf further discloses a compressor (Figure; air compressor) powered based on motion of a shaft (One of the first or second shafts) among the first and second shafts, wherein the compressor is configured to compress the inlet air following heat transfer in the inlet air heat exchanger to obtain pressurized air (The pressurized air from Figure; air compressor. Functional Language, the compressor compresses the inlet air following heat transfer in the inlet air heat exchanger to obtain pressurized air), and wherein the air flow path is configured to supply the pressurized air to the aircraft (Functional Language, the air flow path supplies the pressurized air to the aircraft).
Regarding claim 13, Wolf discloses the invention as claimed.
Wolf further discloses a power shaft (The shaft of Figure; air compressor and first turbine stage);
a compressor (Figure; air compressor) powered by the power shaft and configured to compress the inlet air to obtain pressurized air (The pressurized air from Figure; air compressor. Functional Language, the compressor is powered by the power shaft and compresses the inlet air to obtain pressurized), wherein the air flow path is configured to supply the pressurized air to the aircraft (Functional Language, the air flow path supplies the pressurized air to the aircraft); and
an expander (Figure; first turbine stage) coupled to power the power shaft, wherein the expander is driven by expansion of the fuel in fuel flow path (Functional Language the expander is driven by expansion of the fuel in fuel flow), wherein work performed by the expander is at least equal to the work performed by the compressor (Functional Language, the work done by the expander is at least equal to the work performed by the compressor because when the second turbine stage is fully bypassed, the first turbine stage drives both the air compressor and pump).
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) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wolf in view of Stearns et al (US 20160201563)
Regarding claim 2, Wolf discloses the invention as claimed.
Wolf does not disclose wherein:
the fuel flow path includes a bypass conduit through which the fuel in the fuel flow path can bypass the inlet air heat exchanger, and
a control valve configured to selectively control a fraction of the fuel supplied to the jet engine that is permitted to pass through the bypass conduit and bypass the inlet air heat exchanger.
However, Stearns teaches wherein:
a fuel flow path (The flowpath from Figure 3; 74 to 72) includes a bypass conduit (Figure 3; 132) through which fuel (The fuel in Figure 374,) in the fuel flow path can bypass an inlet air heat exchanger (Figure 3; 80, Paragraph 0071), and
a control valve (Figure 3; 80) configured to selectively control a fraction of the fuel (The fraction of the fuel through Figure 3; 132) supplied to a jet engine (Figure 3; 72, Paragraph 0043, 0047, 0054) that is permitted to pass through the bypass conduit and bypass the inlet air heat exchanger (Functional Language, the control valve selectively control a fraction of the fuel supplied to the jet engine that is permitted to pass through the bypass conduit and bypass the inlet air heat exchanger).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Wolf wherein the fuel flow path includes a bypass conduit through which the fuel in the fuel flow path can bypass the inlet air heat exchanger, and a control valve configured to selectively control a fraction of the fuel supplied to the jet engine that is permitted to pass through the bypass conduit and bypass the inlet air heat exchanger as taught by and suggested by Stearns in order to maintain the temperature of the fuel (Paragraph 0055, the modification adds a bypass conduit and control valve for the inlet air heat exchanger).
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wolf in view of Quartarone et al (US 20230069975)
Regarding claim 5, Wolf discloses the invention as claimed.
Wolf does not disclose a fuel heat exchanger in the fuel flow path before the inlet air heat exchanger configured to transfer heat from the cooled and pressurized air to the fuel in the fuel flow path.
However, Quartarone teaches a fuel heat exchanger (Figure 4; 410) in a fuel flow path (The fuel path from Figure 4; 402 to 412) before an inlet air heat exchanger (Figure 4; 432. Paragraph 0049 states gas can be used as the other working fluid, so that 432 can be an inlet air heat exchanger) configured to transfer heat from cooled and pressurized air (The air exiting Figure 4; 416 is a cooled and pressurized air) to fuel (The fuel in the fuel path) in the fuel flow path.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Wolf to include a fuel heat exchanger in the fuel flow path before the inlet air heat exchanger configured to transfer heat from the cooled and pressurized air to the fuel in the fuel flow path as taught by and suggested by Quartarone in order to provide the fuel at increased temperatures (Paragraph 0046, 0049, The modification adds a fuel heat exchanger upstream of the inlet air heat exchanger).
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wolf in view of Quartarone as applied to claim 5 above, and further in view of Niergarth et al (US 20190153952).
Regarding claim 6, Wolf in view of Quartarone teaches the invention as claimed.
Wolf in view of Quartarone does not teach a control valve configured to selectively control a fraction of the fuel in the fuel flow path that is permitted to pass through the fuel heat exchanger.
However, Niergarth teaches a control valve (Figure 2; 164) configured to selectively control a fraction of fuel in a fuel flow path (The fraction of the fuel in the fuel flow path from Figure 2; 130 to 124 that goes through 108A, Paragraph 0083) that is permitted to pass through a fuel heat exchanger (Figure 2; 108A)
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Wolf in view of Quartarone to include a control valve configured to selectively control a fraction of the fuel in the fuel flow path that is permitted to pass through the fuel heat exchanger as taught by and suggested by Niergarth in order to bypass the fuel heat exchanger (Paragraph 0079, the modification adds a bypass and valve around the fuel heat exchanger).
Claim(s) 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wolf in view of Quartarone et al (US 20230069975)
Regarding claim 12, Wolf discloses the invention as claimed.
Wolf does not disclose a body heat exchanger configured to transfer heat from a body cooling loop of the aircraft to the air flow path.
However, Pal teaches a body heat exchanger (Figure 7; 108) configured to transfer heat from a body cooling loop (The heat of the cooling loop of Figure 7; 108, 102, 106E) of an aircraft (Paragraph 0054) to an air flow path (The flowpath of air through at least Figure 7; 22, 24).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Wolf to include a body heat exchanger configured to transfer heat from a body cooling loop of the aircraft to the air flow path as taught by and suggested by Pal in order to conserve heat/energy during operations (Paragraph 0081, The modification adds a body heat exchanger to the air compressor of Wolf).
Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wolf in view of Ribeiro et al (US 20230024316)
Regarding claim 14, Wolf discloses the invention as claimed.
Wolf further discloses the aircraft, comprising:
a fuel tank (Figure; fuel tank); and
a fuel pump (Figure; pump) coupled to the fuel tank; and
the apparatus of Claim 1 coupled by the fuel flow path to the fuel pump and the air flow path to the jet engine.
Wolf does not disclose the aircraft, comprising:
an airframe,
a wing assembly coupled to the airframe;
at least one of the jet engine coupled to the airframe,
a fuel tank configured to hold cryogenic fuel in a liquid state.
However, Ribeiro teaches an aircraft (Figure 1A), comprising:
an airframe (The airframe of Figure 1A which includes at least the fuselage of Figure 1A),
a wing assembly (The wing assembly of Figure 1A) coupled to the airframe;
at least one of a jet engine (Figure 1A; 2a, 2b) coupled to the airframe,
a fuel tank (Figure 1A; 1a, 1b) configured to hold cryogenic fuel in a liquid state (Functional Language, Paragraph 0004, 0025).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Wolf to include an aircraft, comprising: an airframe, a wing assembly coupled to the airframe; at least one of the jet engine coupled to the airframe, a fuel tank configured to hold cryogenic fuel in a liquid state as taught by and suggested by Ribeiro in order to decrease installation burden (The modification makes the fuel tank of Wolf a cryogenic fuel tank) and because it has been held that applying a known technique, in this case Ribeiro’s formation of an aircraft according to the steps described immediately above, to a known device, in this case, Wolf’s aircraft, ready for improvement to yield predictable results, in this case forming an aircraft, was an obvious extension of prior art teachings, KSR, 550 U.S. 398 (2007), 82 USPQ2d at 1396; MPEP 2143(D) (The modification uses the components of Ribeiro in Wolf).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to EDWIN G KANG whose telephone number is (571)272-9814. The examiner can normally be reached Mon-Fri 8:00-5:00 PM EST.
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/EDWIN KANG/Primary Examiner, Art Unit 3741
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