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 .
Status of Claims
This Office Action is in response to the Response to Non-Final Rejection filed December 19, 2025. Claims 1-20 are presently pending and presented for examination.
Response to Arguments
Applicant’s arguments with respect to claims 1-20 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
An updated and detailed rejection follows below.
Claim Rejections - 35 USC § 103
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.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-8, 10-12, and 15-20, are rejected under 35 U.S.C. 103 as being unpatentable over Hiett et al. (US 20230358169; hereinafter Hiett, already of record in IDS), in view of Romero et al. (US 20200248619; hereinafter Romero, already of record), and further in view of Morgan et al. (US 20230203989; hereinafter Morgan).
Regarding Claim 1,
Hiett teaches
A hybrid engine (Hiett: Abstract) comprising:
a gas turbine engine having at least one compressor rotor connected to be driven by at least one turbine rotor, (Hiett: Paragraph [0032], [0036]-[0037]) a combustor connected to receive compressed air from the at least one compressor rotor, and to receive fuel; (Hiett: Paragraph [0036]; Combustion Section 40)
at least one electric motor connected to drive the at least one compressor rotor to supplement drive in combination with the at least one turbine rotor; (Hiett: Paragraph [0030], [0049]-[0050], [0063]) and
a hybrid engine controller comprising processing circuitry and a memory storing instructions (Hiett: Paragraph [0055], [0058]-[0059]; Engine Controller 210) that, when executed cause the processing circuitry to:
control a flow of the fuel to the combustor; (Hiett: Paragraph [0055])
control the at least one electric motor; (Hiett: Paragraph [0054])
...
Both Hiett and Romero teach a Hybrid-Electric jet engine for an aircraft, however Hiett does not explicitly teach the sensor feedback and compressor or fuel control of the present invention. However in the same field of endeavor, Romero teaches,
...
receive feedback on an operating condition of the hybrid engine indicative of a failure of the at least one electric motor; (Romero: Paragraph [0049]-[0051]; “At block 510, the controller 216 can determine whether a fault was detected by at least one of the management systems, such as a thermal management system 504, a battery management system 506, and/or an electric augmentation management system 508.”)
...
It would be obvious for one with ordinary skill in the art before the effective filling date of the claimed invention to modify the Hybrid-Electric jet engine of Hiett with the compressor monitoring system of Romero for the benefit of increased engine operating efficiency. (Romero: Paragraph [0003])
Hiett, in view of Romero does not explicitly teach controlling the amount fuel being delivered to the combustor based on certain conditions. However in the same field of endeavor, Morgan teaches
...
control an amount of fuel delivered to the combustor to drive the at least one compressor rotor to, in a first mode, operate at a compressor pressure ratio spaced from a stall pressure ratio that could result in a stall of the at least one compressor based on the operating condition not indicating a potential failure of the at least one electric motor; (Morgan: Paragraph [0027]-[0029], [0070], [0086], FIG. 3A and 3B; When no error is detected in the electrical generator, the power of the generator may be increased when the thrust from the fuel powered engine is reduced (e.g. the fuel flow is reduced to the combustor) in order to keep ratio of the compressor spaced adequately away from the stall margin.) and
control the amount of fuel delivered to drive the at least one compressor rotor to move to a second mode where the compressor pressure ratio is closer to the stall pressure ratio than in the first mode based on the hybrid engine controller determining that a failure of the at least one electric motor failure occurred. (Morgan: Paragraph [0088]; “One condition that may be present with examples of such an approach is that a gas turbine engine may have reduced, and perhaps insufficient stall margin should the generator fail. Accordingly, an engine design and operating procedure may include a FADEC or other controller that reverts to a reversionary logic, which limits the acceleration and deceleration rates of the gas turbine engine such that stall margin can be maintained.”; FIG. 6 (Element 96); “Reduce deceleration schedule (slower rate of fuel flow reduction) to preserve stall margin)”)
It would be obvious for one with ordinary skill in the art before the effective filling date of the claimed invention to modify the Hybrid-Electric jet engine of Hiett, in view of Romero, with the fuel delivery control system of Morgan for the benefit of causing a reduction in the fan working line and allow the fan to recover from a stall or surge. (Morgan: Paragraph [0031])
Regarding Claim 2,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 1, wherein the at least one compressor rotor includes a low pressure compressor (Hiett: Paragraph [0063], FIG. 3; Low Pressure Compressor 202) and a high pressure compressor, (Hiett: Paragraph [0063], FIG. 3; High Pressure Compressor 203) and the at least one turbine rotor includes a high pressure turbine (Hiett: Paragraph [0036], FIG. 2; High Speed Turbine 36) and a low pressure turbine, (Hiett: Paragraph [0037], FIG. 2; Low Speed Turbine 42) the low pressure turbine driving the low pressure compressor through a shaft as a low pressure spool, (Hiett: Paragraph [0037], FIG. 2; Low Speed Spool 55) and the high pressure turbine driving the high pressure compressor through a shaft as a high pressure spool. (Hiett: Paragraph [0036], FIG. 2; High Speed Shaft 38)
Regarding Claim 3,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 2, wherein the low pressure spool further includes a propulsor. (Hiett: Paragraph [0041], FIG. 2; Rotor Assembly 12)
Regarding Claim 4,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 3, wherein the propulsor is driven through a gear reduction. (Hiett: Paragraph [0042], FIG. 2; Power Gearbox 56)
Regarding Claim 5,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 2, wherein the at least one electric motor includes a first electric motor driving the low pressure spool (Hiett: Paragraph [0063], [0065]; Low Pressure (LP) Electric Machine 204) and a second electric motor driving the high pressure spool. (Hiett: Paragraph [0063], [0065]; High Pressure (HP) Electric Machine 205)
Regarding Claim 6,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 2, wherein the operating condition indicative of a potential failure in the at least one electric motor is the speed of the low pressure spool. (Hiett: Paragraph [0073]-[0074])
Regarding Claim 7,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 2, wherein the high pressure compressor is the at least one compressor controlled by the hybrid engine between the first and second modes. (Romero: Paragraph [0051]; “If at least one fault was detected at block 510, a management systems status assessment 514 can be performed and an emergency bleed flow 516 can be used as a bleed request 517 that modifies the engine bleed schedule 228. The bleed request 517 can open one or more engine bleeds 232 to reduce the high pressure compressor 52 pressure ratio.”)
The motivation to combine Hiett, Romero, and Morgan, is the same as stated for Claim 1 above.
Regarding Claim 8,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 2, wherein the condition indicative of the potential failure in the electric motor is the thrust provided by the hybrid engine. (Hiett: Paragraph [0073]; One compressor experiencing stall)
Regarding Claim 10,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 2, wherein the instructions, when executed, cause the processing circuitry to:
in the first mode, control the compressor pressure ratio across the high pressure compressor to be spaced from the stall pressure ratio by a first higher percentage; (Romero: Paragraph [0051]; “Based on determining that no faults were detected, nominal bleeds 512 can be maintained as a bleed request 513 to one or more engine bleeds 232, for instance, according to the engine bleed schedule 228. The bleed request 513 can open or close one or more engine bleed valves at various stations within the gas turbine engine 120.”) and
in the second mode move the compressor pressure ratio to be closer to the stall pressure ratio than it is in the first mode. (Romero: Paragraph [0051]; “If at least one fault was detected at block 510, a management systems status assessment 514 can be performed and an emergency bleed flow 516 can be used as a bleed request 517 that modifies the engine bleed schedule 228. The bleed request 517 can open one or more engine bleeds 232 to reduce the high pressure compressor 52 pressure ratio.”)
The motivation to combine Hiett, Romero, and Morgan, is the same as stated for Claim 1 above.
Regarding Claim 11,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 1, wherein a percentage difference between the compressor pressure ratio and the stall pressure ratio in the second mode is less than five percent. (Romero: Paragraph [0051], FIG. 3 (Element 304 and 305); “...modification of the engine bleed schedule 228 can be combined with modification of the acceleration schedule 226 to produce the slowed transient response 312 of the transient acceleration condition 305 below the stall line boundary 304.” When a fault is detected, the system is configured to bleed the compressor system so that the pressure ratio of the High Pressure Compressor drops to the pressure ratio corresponding to the stall line (i.e. 0% which is less than 5%).)
The motivation to combine Hiett, Romero, and Morgan, is the same as stated for Claim 1 above.
Regarding Claim 12,
Hiett, in view of Romero, and further in view of Morgan, teaches
The hybrid engine as set forth in claim 11, wherein the percentage difference is less than two percent. (Romero: Paragraph [0051], FIG. 3 (Element 304 and 305); “...modification of the engine bleed schedule 228 can be combined with modification of the acceleration schedule 226 to produce the slowed transient response 312 of the transient acceleration condition 305 below the stall line boundary 304.” When a fault is detected, the system is configured to bleed the compressor system so that the pressure ratio of the High Pressure Compressor drops to the pressure ratio corresponding to the stall line (i.e. 0% which is less than 2%).)
The motivation to combine Hiett, Romero, and Morgan, is the same as stated for Claim 1 above.
Regarding Claim 15, the claim is analogous to Claim 1 limitations and is therefore rejected under the same premise as Claim 1.
Regarding Claim 16, the claim is analogous to Claim 2 limitations and is therefore rejected under the same premise as Claim 2.
Regarding Claim 17, the claim is analogous to Claim 6 limitations and is therefore rejected under the same premise as Claim 6.
Regarding Claim 18, the claim is analogous to Claim 10 limitations and is therefore rejected under the same premise as Claim 10.
Regarding Claim 19, the claim is analogous to Claim 10 limitations and is therefore rejected under the same premise as Claim 10.
Regarding Claim 20, the claim is analogous to Claim 8 limitations and is therefore rejected under the same premise as Claim 8.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Hiett, in view of Romero, and further in view of Morgan, as applied to claims 1-8, 10-12, and 15-20, above, and further in view of Fuller et al. (US 20120060505; hereinafter Fuller, already of record).
Regarding Claim 9,
Hiett, in view of Romero, and further in view of Morgan, teaches the hybrid engine as set forth in claim 2, however they do not teach that the hybrid controller is a model predictive control.
However in the same field of endeavor, Fuller teaches
...wherein the hybrid engine controller is a model predictive control. (Fuller: Paragraph [0022])
It would be obvious for one with ordinary skill in the art before the effective filling date of the claimed invention to modify the hybrid engine of Hiett, in view of Romero, and further in view of Morgan, with the model predictive control of Fuller for the benefit of adaptively controlling a gas turbine engine during both nominal and off-nominal operation. (Fuller: Paragraph [0015])
Claims 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Hiett, in view of Romero, and further in view of Morgan, as applied to claims 1-8, 10-12, and 15-20, above, and further in view of Greenberg et al. (US 20220397067; hereinafter Greenberg, already of record).
Regarding Claim 13,
Hiett, in view of Romero, and further in view of Morgan, teaches the hybrid engine as set forth in claim 1, however they do not teach the various instructions to adjust the pressure ratio of the compressor to be equal to the stall pressure ratio for at least an early portion of operation of the engine.
However in the same field of endeavor, Greenburg teaches
...wherein the instructions, when executed cause the processing circuitry to attempt to keep the compressor pressure ratio equal to the stall pressure ratio for at least an early portion of operation of the hybrid engine. (Greenberg: Paragraph [0056]-[0057]; The electric machine may be utilized to adjust the rotation speeds of the spools in order to operate the engine at a lower speed/pressure (which would typically stall an aircraft not equipped with a hybrid system) without stalling the engine.)
It would be obvious for one with ordinary skill in the art before the effective filling date of the claimed invention to modify the hybrid engine of Hiett, in view of Romero, and further in view of Morgan, and further in view of Morgan, with the compressor pressure ratio control of Greenburg for the benefit of an aircraft engine with mechanisms to avoid stall events and other adverse conditions. (Greenberg: Paragraph [0002])
Regarding Claim 14,
Hiett, in view of Romero, further in view of Morgan, and further in view of Greenburg, teaches
The hybrid engine as set forth in claim 13, wherein the early portion of the operation of the hybrid engine occurs at a take-off condition of an associated aircraft. (Greenberg: Paragraph [0053]; “During other transient events, the electric machine can be configured, in an electric motor mode of operation, to add rotational energy to a spool and thereby assist rotation of the spool, thus increasing the rate at which the spool accelerates to the appropriate speed for the specific operational event (e.g., idle to takeoff).”)
The motivation to combine Hiett, Romero, Morgan, and Greenburg, is the same as stated for Claim 13 above.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 PAULO ROBERTO GONZALEZ LEITE whose telephone number is (571)272-5877. The examiner can normally be reached Mon-Fri: 8:00 am - 4:30 pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Abby Flynn can be reached at 571-272-9855. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/P.R.L./Examiner, Art Unit 3663
/ABBY J FLYNN/Supervisory Patent Examiner, Art Unit 3663
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