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 .
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 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.
Claims 1-3, 5, 7-12, and 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over Klingels (DE 102019203595 A1, US patent 11976580 used as an English equivalent) in view of Walsh (6968698), Fletcher (US-Pub 2012/0285175), and Hines (5054279).
Regarding claim 1, Klingels discloses a turbine engine (1, fig 1) for an aircraft, the turbine engine comprising: a turbo-engine (10, fig 1) including: a combustor (15, fig 1) positioned in a core air flow path (fig 1, inner arrow coming from fan 11) to receive compressed air the combustor having a combustion chamber (inside combustor 15, fig 1), the core air flow path including a plurality of core air flow path zones (zones between fan and exhaust at 25, fig 1) for core air to flow therethrough, the combustor fluidly coupled to a fuel source to receive fuel, the fuel being injected into the combustor to mix with the compressed air to generate a fuel and air mixture (one of ordinary skill in the art would recognize the combustion chamber would be connected to a fuel source of some kind, or else the combustor would not run), the fuel and air mixture being combusted in a primary combustion zone (area inside combustor 15, fig 1) of the combustor to generate combustion gases, the primary combustion zone being one zone of the plurality of core air flow path zones and housed in the combustion chamber; an engine shaft (fig 1, there is a shaft along the engine centerlines connecting the compressors and turbines); and a turbine (16, fig 1) located downstream of the combustor to receive the combustion gases and to cause the turbine to rotate, the turbine coupled to the engine shaft to rotate the engine shaft when the turbine rotates; a fan (11, fig 1) having a fan shaft (the fan is driven by the turbine, thus the shaft that is used to turn the fan would be the fan shaft) coupled to the turbo-engine to rotate the fan shaft; and a steam system (12, 22, 25, 41, fig 1) to extract water from the combustion gases and vaporizing the water to generate steam, the steam system being fluidly coupled to the core air flow path to inject the steam into the core air flow path at a plurality of steam injection zones (41, fig 1) to add mass flow to the core air, each steam injection zone of the plurality of steam injection zones corresponding to a core air flow path zone of the plurality of core air flow path zones (injection points 41 lead to the combustor zone and the turbine zone (col 8, lines 1-3), a primary steam injection zone in the primary combustion zone housed in the combustion chamber (combustor 15, fig 1) and a secondary steam injection zone (turbine 16, fig 1).
Klingels does not disclose: wherein the steam system comprises: a primary steam flow control valve operable to control the flow of the steam into a primary steam injection zone positioned in the dome of the plurality of steam injection zones, the primary steam injection zone being positioned in the core air flow path such that the steam injected into the primary steam injection zone flows into the primary combustion zone, and a secondary steam flow control valve operable to control the flow of the steam into a secondary steam injection zone of the plurality of steam injection zones being positioned in a portion of the combustor downstream of the primary combustion zone, a combustor liner passage around an exterior of the combustion chamber, the combustion chamber receiving a first portion of the compressed air and the combustor liner passage receiving a second portion of the compressed air, the secondary steam injection zone being the combustion liner passage around the exterior of the combustion chamber, the second portion of the compressed air being introduced downstream of the primary combustion zone to quench the combustion gasses.
Fletcher teaches a steam injection system for a turbo-engine primary combustion zone (fig 2) wherein the engine includes a primary steam injection zone (outlet of 70, fig 2), the primary steam injection zone being the primary combustion zone (32, fig 2), and a secondary steam injection zone being positioned in a portion of the combustor downstream of the primary combustion zone (72, fig 2).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection system disclosed by Klingels by having a combined fuel and steam injection nozzle to inject steam through the combustor dome into the primary combustion zone based on the teachings of Fletcher. Doing so would allow steam to be injected in a manner that matches the momentum of the fluid flow within the combustor (col 4, lines 4-19), as suggested by Fletcher.
Walsh teaches a water injection system (40, fig 1) for a gas turbine wherein the injection system includes: a primary water flow control valve (57, fig 1) operable to control the flow of the water into a primary injection zone (20, fig 1), the primary injection zone being one injection zone of the plurality of injection zones (57 and 71 control flow to different injection zones, fig 1), the primary injection zone being an injection zone positioned in the core air flow path (core air flows from the inlet compressor 12 all the way out through the exhaust 28, so the injection zone 20 that the control valve 57 leads to is within the core flowpath, fig 1) such that the water injected into the primary injection zone flows into the primary combustion zone; and a secondary flow control valve (71, fig 1) operable to control the flow of the water into a secondary injection zone (between combustor 20 and turbine 22, fig 1), the secondary injection zone being one injection zone of the plurality of injection zones.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection zones disclosed by Klingels by having a control valve which controls the steam injection into the primary and secondary injection zones based on the teachings of Walsh. Doing so would allow the injection to be controlled individually to control the acceleration and deceleration rates of the turbines (col 4, lines 26-46, col 5, lines 1-25), as suggested by Walsh.
Hines teaches a steam and air gas turbine engine combustor (43, fig 2), comprising a combustor liner passage (58, fig 2) around an exterior of the combustion chamber, the combustion chamber receiving a first portion of the compressed air (air coming in a the fuel nozzle which would be required to sustain combustion, fig 2) and the combustor liner passage receiving a second portion of the compressed air (58, fig 2), the secondary steam injection zone (64, fig 2) being the combustion liner passage around the exterior of the combustion chamber, the second portion of the compressed air being introduced downstream of the primary combustion zone to quench (the steam is mixed with dilution air, the purpose of dilution air is to cool the air and prevent further combustion, thus the purpose of the dilution holes is to quench the air) the combustion gasses (last row of inlet arrows near 43, fig 2).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection system disclosed by Klingels as modified by Walsh and Fletcher by injecting secondary steam in the combustion liner passage around the exterior of the combustion chamber before having the second compressed air with the secondary steam be injected into the combustion chamber downstream of the primary combustion zone based on the teachings of Hines. One of ordinary skill in the art would recognize that doing so would allow the steam to cool the combustion liner before being injected into the chamber, allowing the waste heat to be recycled.
Regarding claim 2, Klingels discloses wherein the turbo-engine includes a compressor (between fan 11 and combustor 15, fig 1) positioned in the core air flow path upstream of the combustor to compress the core air to generate the compressed air.
Klingels does not disclose one steam injection zone being downstream of the compressor and upstream of the primary combustion zone.
Walsh teaches a gas turbine condensed water injection system (40, fig 1) wherein one injection zone (55, fig 1) is downstream of the compressor (16, fig 1) and upstream of the primary combustion zone (20, fig 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection zones disclosed by Klingels by having an injection zone downstream of the compressor and upstream of the primary combustion zone based on the teachings of Walsh. Doing so would allow the injection to be controlled to maximize acceleration and power without exceeding the compressor surge margin (col 4, lines 26-46), as suggested by Walsh.
Regarding claim 3, Klingels discloses wherein the turbo-engine includes a compressor (between fan 11 and combustor 15, fig 1) positioned in the core air flow path upstream of the combustor to compress the core air to generate the compressed air.
Klingels does not disclose wherein one steam injection zone being downstream of the compressor and upstream of the combustor.
Walsh teaches a gas turbine condensed water injection system (40, fig 1) wherein one injection zone (55, fig 1) is downstream of the compressor (16, fig 1) and upstream of the combustor (20, fig 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection zones disclosed by Klingels by having an injection zone downstream of the compressor and upstream of the combustor based on the teachings of Walsh. Doing so would allow the injection to be controlled to maximize acceleration and power without exceeding the compressor surge margin (col 4, lines 26-46), as suggested by Walsh.
Regarding claim 5, Klingels does not disclose wherein the engine includes a combined fuel and steam nozzle assembly to inject both the steam and the fuel into the primary combustion zone.
Hines teaches a steam and air gas turbine engine, wherein the engine includes a combined fuel and steam nozzle assembly (44, fig 2) to inject both the steam and the fuel into the primary combustion zone.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection system disclosed by Klingels as modified by Walsh and Fletcher by having a combined fuel and steam nozzle assembly based on the teachings of Hines. Doing so would prevent NOX formation at the start of combustion (col 3, lines 55-66), as suggested by Hines.
Regarding claim 7, Klingels as modified by Fletcher discloses wherein the secondary steam injection zone in the combustor is a cooling flow path (72, fig 2, Fletcher, the passage forms a flow path and the steam is lower temperature than the combustor, thus the injection passage 72 serves as a cooling flow path which serves as the secondary injection zone).
Regarding claim 8, Klingels discloses wherein one steam injection zone is downstream of the combustor in the turbine (col 8, lines 1-3).
Regarding claim 9, Klingels discloses wherein one steam injection zone is an inlet of the turbine (41, fig 1, the steam injection arrow is directed at the turbine inlet).
Regarding claim 10, Klingels discloses wherein the turbine includes a turbine cooling passage (41, fig 1 the passage injects steam which is cooler than the turbine it is being injected into, meaning the steam injection passage would be a turbine cooling passage), the steam being injected into the turbine through the turbine cooling passage.
Regarding claim 11, Klingels discloses wherein the turbine is a high-pressure turbine (16, fig 1, the upper turbine section closer to 15 is a high pressure turbine).
Regarding claim 12, Klingels discloses having a low pressure turbine (16, fig 1 the second turbine further from combustor 15), and wherein the turbine can have steam injected at multiple stages (col 8, lines 1-3).
Klingels does not disclose wherein the turbine the steam is injected is a low-pressure turbine.
Walsh teaches a water injection control system (40, fig 1), where water can be injected into the low pressure turbine (64, 24, fig 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection zones disclosed by Klingels by having an injection zone at the low pressure turbine based on the teachings of Walsh. Doing so would allow the injection to be controlled individually to control deceleration rates of the turbines (col 5, lines 1-25), as suggested by Walsh.
Regarding claim 15, Klingels as modified by Walsh discloses a controller (col 4, lines 26-46, Walsh, the valves are controlled, meaning that there would be a controller to operate the valves) operatively coupled to the primary steam flow control valve and configured to adjust the position of the primary steam flow control valve to control the flow of the steam into the primary steam injection zone (col 4, lines 26-46, Walsh).
Regarding claim 16, Klingels as modified by Walsh discloses wherein the controller is operatively coupled to the secondary steam flow control valve and configured to adjust the position of the secondary steam flow control valve to control the flow of the steam into the secondary steam injection zone (col 5, lines 1-25, Walsh).
Claims 21-23 are rejected under 35 U.S.C. 103 as being unpatentable over Klingels in view of Tazaki (6502403).
Regarding claim 21, Klingels discloses a turbine engine (1, fig 1) for an aircraft, the turbine engine comprising: a turbo-engine (10, fig 1) including: a combustor (15, fig 1) positioned in a core air flow path (fig 1, inner arrow coming from fan 11) to receive compressed air the combustor having a combustion chamber (inside combustor 15, fig 1), the core air flow path including a plurality of core air flow path zones (zones between fan and exhaust at 25, fig 1) for core air to flow therethrough, the combustor fluidly coupled to a fuel source to receive fuel, the fuel being injected into the combustor to mix with the compressed air to generate a fuel and air mixture (one of ordinary skill in the art would recognize the combustion chamber would be connected to a fuel source of some kind, or else the combustor would not run), the fuel and air mixture being combusted in a primary combustion zone (area inside combustor 15, fig 1) of the combustor to generate combustion gases, the primary combustion zone being one zone of the plurality of core air flow path zones and housed in the combustion chamber; an engine shaft (fig 1, there is a shaft along the engine centerlines connecting the compressors and turbines); and a turbine (16, fig 1) located downstream of the combustor to receive the combustion gases and to cause the turbine to rotate, the turbine coupled to the engine shaft to rotate the engine shaft when the turbine rotates; a fan (11, fig 1) having a fan shaft (the fan is driven by the turbine, thus the shaft that is used to turn the fan would be the fan shaft) coupled to the turbo-engine to rotate the fan shaft; and a steam system (12, 22, 25, 41, fig 1) to extract water from the combustion gases and vaporizing the water to generate steam, the steam system being fluidly coupled to the core air flow path to inject the steam into the core air flow path at a plurality of steam injection zones (41, fig 1) to add mass flow to the core air, each steam injection zone of the plurality of steam injection zones corresponding to a core air flow path zone of the plurality of core air flow path zones (injection points 41 lead to the combustor zone and the turbine zone (col 8, lines 1-3), a primary steam injection zone in the primary combustion zone housed in the combustion chamber (combustor 15, fig 1) and a secondary steam injection zone (turbine 16, fig 1).
Klingels does not disclose: wherein the steam system comprises: the primary steam injection zone being positioned in the core air flow path such that the steam injected into the primary steam injection zone flows into the primary combustion zone, and a secondary steam injection zone of the plurality of steam injection zones being positioned in a portion of the combustor downstream of the primary combustion zone, a combustor liner passage around an exterior of the combustion chamber, the combustion chamber receiving a first portion of the compressed air and the combustor liner passage receiving a second portion of the compressed air, the secondary steam injection zone being the combustion liner passage around the exterior of the combustion chamber, the second portion of the compressed air being introduced downstream of the primary combustion zone to quench the combustion gasses.
Tazaki teaches a steam injection gas turbine (fig 1), wherein steam injection includes a primary steam outlet (52, fig 2) operable to control the flow of steam into a primary injection zone (at the front entrance of the combustor 3, fig 2), the primary injection zone being the primary injection zone being one injection zone of the plurality of injection zones (arrows A, fig 2), the primary injection zone being an injection zone positioned in the core air flow path (A, fig 2) such that the water injected into the primary injection zone flows into the primary combustion zone (the steam is injected along with the fuel into the primary combustion zone; and a secondary outlet (44, fig 2) operable to control the flow of the water into a secondary injection zone (42, fig 2), the secondary injection zone being one injection zone of the plurality of injection zones, the secondary injection zone being a combustor liner passage (42, fig 2) around an exterior of the combustion chamber, the combustion chamber receiving a first portion of the compressed air and the combustor liner passage receiving a second portion of the compressed air (arrows A show air coming from both the nozzle head and the combustion liner, fig 2), the secondary steam injection zone (64, fig 2) being the combustion liner passage around the exterior of the combustion chamber, the second portion of the compressed air being introduced downstream of the primary combustion zone to quench the combustion gasses (this represents the intended use of the air, as the air is injected downstream of the primary combustion zone, it would quench the combustion gasses as per the claim).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection system disclosed by Klingels by injecting a primary steam into the primary combustion zone and a secondary steam in the combustion liner passage around the exterior of the combustion chamber and then injecting the second portion of the compressed air downstream of the primary combustion zone based on the teachings of Tazaki. Doing so would allow the engine to balance between NOx production and power production (col 5, lines 35-60).
Regarding claim 22, Klingels as modified by Tazaki in claim 21 discloses wherein the steam system further comprises a steam control valve (27, fig 2, Tazaki) operable to control the flow of steam through both the primary outlet and the secondary outlet.
Regarding claim 23, Klingels as modified by Tazaki in claim 21 discloses wherein the steam control valve is a proportional steam control valve operable to proportion the flow of steam between the primary outlet and the secondary outlet (the valve 27 is merely a distribution valve to distribute steam between the first and second outlet, meaning that whatever amount it gives to those two spots would be proportional).
Claims 17 and 25 are is rejected under 35 U.S.C. 103 as being unpatentable over Klingels as modified by Walsh, Hines, and Fletcher as applied to claim 15 above, and further in view of Corbett (5369951).
Regarding claim 17, Klingels as modified by Walsh discloses wherein the controller is configured to determine if the turbine engine is being accelerated or decelerated (col 4, lines 22-25, Walsh), wherein, when the controller determines that the turbine engine is being accelerated, the controller is configured to open the primary steam flow control valve to increase the flow of the steam into the primary steam injection zone (col 4, lines 26-46, Walsh).
Klingels as modified by Walsh does not disclose when the controller determines that the turbine engine is being decelerated, the controller is configured to close the primary steam flow control valve to decrease the flow of the steam into the primary steam injection zone.
Corbett teaches a steam injection system for a gas turbine (48, fig 1), wherein when the controller (50, fig 1) determines that the engine is being decelerated, the controller is configured to close the primary steam flow control valve to decrease the flow of steam into the primary steam injection zone (col 10, lines 1-6).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection system disclosed by Klingels as modified by Walsh by configuring the controller to close the primary steam flow control valve to decrease steam flow to the primary steam injection zone when the engine is being decelerated based on the teachings of Corbett. Doing so would prevent engine flameout during deceleration (col 10, lines 1-6), as suggested by Corbett.
Regarding claim 25, Klingels as modified by Walsh, Fletcher, and Corbett discloses wherein, when the controller determines that the turbine engine is being decelerated, the controller: controls the primary steam flow control valve to decrease the flow of the steam into the primary steam injection zone (col 10, lines 1-6, Corbett); controls the secondary steam flow control valve to decrease the flow of the steam into the secondary steam injection zone (col 10, lines 1-6, the flow can be stopped completely in the case of sudden deceleration); and after at least controlling the primary steam flow control valve to decrease the flow of the steam into the primary steam injection zone, controls a flow of fuel to decrease the fuel injected into the combustor (col 10, lines 1-6, the flow needs to be stopped completely in order to prevent a flame out of the combustor due to excessive steam, if the fuel was stopped first, there would be a flame out, thus, in order for this to operate correctly, the steam would need to be decreased before the fuel is decreased in order to clear the steam and prevent the flameout).
Claims 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Klingels as modified by Walsh, Hines and Fletcher as applied to claim 1 above, and further in view of Nielson (5797259).
Regarding claim 18, Klingels as modified by Walsh discloses a tertiary flow control valve (Walsh, Fig 1, there are far more valves than a first and second valve)
Klingels as modified by Walsh does not disclose the tertiary steam flow control valve is a pressure regulating valve operable to inject steam at an output pressure proportional to a control pressure.
Nielson teaches a steam flow control valve (36, fig 3) which injects cooling steam into a location downstream of a primary combustion zone (13, fig 1), wherein the flow control valve is a pressure regulating valve (col 5, lines 13-60, the regulator valve operates based on the air pressure of the exit), wherein, when the turbine engine is being accelerated, the secondary steam flow control valve passively operates to increase the flow of the steam into the secondary steam injection zone based on the control pressure, and wherein, when the turbine engine is being decelerated, the secondary steam flow control valve passively operates to decrease the flow of the steam into the secondary steam injection zone based on the control pressure (this represents intended use of the steam control valve, since the valve operates based off of pressure of the turbine engine, as the pressure changes from accelerating and decelerating the engine, it would change in a way which would match the claimed operation).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the steam injection system disclosed by Klingels as modified by Walsh by having the secondary steam flow control valve be a pressure regulating valve based on the teachings of Nielson. One of ordinary skill in the art would recognize that using a pressure regulating valve would allow for automated control of the amount of steam injected without the need for external controls or sensors.
Regarding claim 19, Klingels as modified by Walsh and Nielson discloses wherein the control pressure is a pressure of the core air (the valve outlet is in connection with the core air 11, meaning the core air would serve as the pressure regulating air, Nielson).
Regarding claim 20, Klingels as modified by Walsh and Nielson discloses wherein the turbo-engine includes a compressor (between 11 and 15 is a compressor, Klingels, fig 1) positioned in the core air flow path upstream of the combustor to compress the core air to generate the compressed air, the control pressure being the pressure of the core air at an outlet of the compressor (the core air 11 is directly from the compressor outlet as can be seen in fig 1 of Nielson, meaning the core air pressure that is used is the pressure from the compressor air outlet).
Claim 24 is rejected under 35 U.S.C. 103 as being unpatentable over Klingels as modified by Walsh, Hines and Fletcher as applied to claim 1 above, and further in view of Hagen (4062184).
Regarding claim 24, Klingels is silent as to the type of fuel used.
Hagen teaches using hydrogen as a fuel for a gas turbine engine (col 1, lines 5-13).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used hydrogen fuel in the gas turbine of Klingels based on the teachings of Hagen. One of ordinary skill in the art would recognize that hydrogen has extremely high specific impulse and thus is one of the most efficient fuels available for use in turbine engines.
Response to Arguments
Applicant's arguments filed 3/6/2026 have been fully considered but they are not persuasive. Applicant argues that the claims overcome the current rejection as per the interview summary from the interview on 1/27/2026. However, the interview summary states that “the second portion of compressed air bypasses the primary combustion zone and enters the chamber in the second combustion zone” while the amendment reads “the second portion of the compressed air being introduced downstream of the primary combustion zone to quench the combustion gasses” which is of a materially different scope of the agreed upon language.
Applicant’s arguments, see remarks, filed 3/6/2026, with respect to the claim objections have been fully considered and are persuasive. The objections of 11/6/2025 has been withdrawn.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SEAN V MEILLER whose telephone number is (571)272-9229. The examiner can normally be reached 7am-5pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Devon Kramer can be reached at 571-272-7118. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/SEAN V MEILLER/Examiner, Art Unit 3741
/DEVON C KRAMER/Supervisory Patent Examiner, Art Unit 3741