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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 02/26/2026 has been entered.
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.
Claim 21 is 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 21, it is unclear whether term “a second flow control valve” refers to i) the main fuel circuit flow control valve previously claimed in claim 1; or ii) a different valve in addition to the main fuel circuit flow control valve previously claimed in claim 1.
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.
Claims 1, 3-4, 7-8, and 21 are rejected under 35 U.S.C. 103 as being unpatentable over Xuening 20230050741 in view of Patra 20230304665.
Regarding claim 1, Xuening teaches the invention as claimed: A system (200, Fig. 2) for delivering a fuel (hydrogen fuel from 124, see Fig. 2 and [0034]) to a gas turbine engine (100, Fig. 1), the gas turbine engine (100) having a combustor (108, Figs. 1-2) and a plurality of injectors (120a and 120b, Fig. 2) circumferentially arranged about the combustor (108, see Fig. 2), the system comprising:
a start fuel circuit (110a and 110 in Fig. 2, and per [0034, 0039, and 0041], 110 provides fuel to 120a during start-up) configured to be fluidly coupled to one or more first injectors (120a) of the plurality of injectors to facilitate injection of a first quantity of the fuel (a first quantity of the fuel provided to injectors 120a, [0039]) by the one or more first injectors (120a) into one or more first zones (the first zones corresponding to injectors 120a, see Fig. 2) of the combustor (108) for ignition (per [0040 and 0053], the flow of the first quantity of fuel is controlled by flow modulating valve 150 according to operation condition, e.g., start-up or high power); and
at least one main fuel circuit (111a and 111 in Fig. 2, and per [0034, 0039, and 0041], 111 provides fuel to 120b during the high power condition) configured to be fluidly coupled to one or more second injectors (120b) of the plurality of injectors to facilitate injection of a second quantity of the fuel (a second quantity of the fuel provided to injectors 120b, [0039]) by the one or more second injectors (120b) into one or more second zones (the second zones corresponding to injectors 120b, see Fig. 2) of the combustor (118; per [0040 and 0053], the flow of the second quantity of fuel is controlled by flow modulating valve 152 according to operation condition, e.g., start-up and high power) in response to a power increasing of the gas turbine engine ([0039 and 0041]), the at least one main fuel circuit (111a and 111 in Fig. 2) including a main fuel circuit flow control valve (152, Fig. 2), and
wherein, for ignition during start-up:
the one or more first injectors (120a, Fig. 2) of the plurality of injectors is configured to inject the first quantity of fuel (the first quantity of the fuel provided to injectors 120a during start-up controlled by the flow modulating valve 150, see [0039, 0040, and 0053]), and
the main fuel circuit flow control valve (152, Fig. 2) is configured to be in a first state (a closed state) to restrict the second quantity of fuel (per [0041], during start-up, valve 152 remains closed, and thus, the second quantity of the fuel provided to injectors 120b is restricted) from the one or more second injectors (120b, Fig. 2) by an amount (no fuel is delivered to injectors 120b during start-up, see [0041]).
Xuening does not teach an ignition source activated during start-up, and at least one torch fuel circuit configured to be fluidly coupled to the ignition source.
However, Patra teaches a system for delivering a fuel (hydrogen fuel, [0039]) to a gas turbine engine (10, Fig. 1), the gas turbine engine (10, Fig. 1) comprising an ignition source (torch ignitor 130, see Figs. 4-5A and [0035]) activated during start-up (by controlling a flow of ignition fuel 136 during start-up, see [0050]), and the system comprising: at least one torch fuel circuit (in order to provide the flow of ignition fuel 136 in Fig. 4, which is a separated fuel circuit from a combustion fuel circuit, see [0039 and 0049-0050]) configured to be fluidly coupled to the ignition source (130) of the gas turbine engine.
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to provide Xuening with Patra’s ignition source activated during start-up and at least one torch fuel circuit configured to be fluidly coupled to the ignition source of the gas turbine engine because: comparing to conventional ignitor designed for traditional fuel ignition, Patra’s torch ignitor is designed for hydrogen fuel ignition, especially pure hydrogen (wherein Xuening’s fuel is pure hydrogen as explained above), in order to control the combustion to occur at desired location or to have desired shape (Patra, [0060]).
Xuening in view of Patra does not teach a start fuel circuit configured to facilitate injection of a first quantity of the fuel by the one or more first injectors into one or more first zones of the combustor upon activation of an ignition source of the gas turbine engine; at least one main fuel circuit configured to facilitate injection of a second quantity of the fuel by the one or more second injectors into one or more second zones of the combustor in response to a light-off of the first quantity of the fuel, and wherein, upon the activation of the ignition source: the one or more first injectors of the plurality of injectors is configured to inject the first quantity of fuel, and the main fuel circuit flow control valve is configured to be in a first state to restrict the second quantity of fuel from the one or more second injectors by an amount that maintains a concentration of the fuel in a fuel-air mixture downstream of the combustor below a lower flammability limit of the fuel, which are functional limitations.
However, it is noted, “apparatus claims, i.e., a system as taught by Xuening in view of Patra, cover what a device is, not what a device does. A claim containing a recitation with respect to the manner in which a claimed apparatus is intended to be employed, i.e., … facilitate injection of a first quantity of the fuel … upon activation of an ignition source of the gas turbine engine; … facilitate injection of a second quantity of the fuel … in response to a light-off of the first quantity of the fuel, and wherein, upon the activation of the ignition source … inject the first quantity of fuel and … restrict the second quantity of fuel … by an amount that maintains a concentration of the fuel in a fuel-air mixture downstream of the combustor below a lower flammability limit of the fuel, does not differentiate the claimed apparatus from a prior art apparatus, if the prior art apparatus teaches all the structural limitations of the claim, i.e., as taught by as taught by Xuening in view of Patra as discussed above”, MPEP 2114(II). It is noted that the system as taught by Xuening in view of Patra is capable of performing the claimed functions.
Regarding claim 3, Xuening further teaches wherein the start fuel circuit (110a and 110, Fig. 2) includes:
a start fuel manifold (110) including an inlet port (where 110a and 110 meet, see Fig. 2) for receiving the fuel into the start fuel manifold (110) and one or more outlet ports (the ports of where 110 connect to injectors 120a, see Fig. 2) for correspondingly supplying the fuel to the one or more first injectors (120a) from the start fuel manifold (110, see [0034, 0039, and 0041]); and
a first flow control valve (150, Fig. 2) fluidly coupled to the inlet port (where 110a and 110 meet, see Fig. 2), the first flow control valve (150) configured to move between a plurality of positions (per [0040], valve 150 may be a variable opening, electrically actuated valve) including a first position (a closed position per [0040]) and a second position (an open position per [0040]), wherein:
at the first position (the closed position), the fuel is restricted to flow towards the inlet port (where 110a and 110 meet, see Fig. 2) and into the start fuel manifold (110; see [0040]), and
at the second position (the open position), the fuel is received into the start fuel manifold (110) by the inlet port (where 110a and 110 meet, see Fig. 2) at a predefined first flow rate (the sufficient fuel flow for start-up that is controlled by valve 150, see [0039-0040 and 0052-0053]) to facilitate the injection of the first quantity of the fuel into the one or more first zones (the zones cooperating to injectors 120a) of the combustor (108).
Regarding claim 4, Xuening further teaches wherein the at least one main fuel circuit (111a and 111) includes:
a main fuel manifold (111) including an inlet opening (where 111a and 111 meet, see Fig. 2) for receiving the fuel into the main fuel manifold (111) and one or more outlet openings (the openings of where 111 connect to the injectors 120b, see Fig. 2) for correspondingly supplying the fuel to the one or more second injectors (injectors 120b) from the main fuel manifold (111, see [0034, 0039, and 0041]), wherein
the main fuel circuit flow control valve (152, Fig. 2) is fluidly coupled to the inlet opening (where 111a and 111 meet, see Fig. 2), the main fuel circuit flow control valve (152) configured to move between a plurality of states (per [0040], valve 152 may be a variable opening, electrically actuated valve) including a first state (the closed state per [0040]) and a second state (the open state per [0040]), wherein:
at the first state (the closed state), the fuel is restricted to flow towards the inlet opening (where 111a and 111 meet, see Fig. 2) and into the main fuel manifold (111; see [0040]), and
at the second state (the open state), the fuel is received into the main fuel manifold (111) by the inlet opening (where 111a and 111 meet, see Fig. 2) at a predefined second flow rate (the fuel flow has a sufficient pressure and velocity that is controlled by valve 152, see [0039-0040 and 0052-0053]) to facilitate the injection of the second quantity of the fuel into the one or more second zones (the zones cooperating to injectors 120b) of the combustor (108).
Regarding claim 7, Xuening in view of Patra further teaches wherein the start fuel circuit (Xuening’s 110a and 110 in Xuening’s Fig. 2) is connected to a first flow control valve (Xuening’s 150 in Xuening’s Fig. 2), and the at least one torch fuel circuit (Patra’s torch fuel circuit in order to provide the flow of ignition fuel 136 in Fig. 4, which is a separated fuel circuit from the combustion fuel circuit, see Patra’s [0039 and 0049-0050]) is connected to a torch fuel circuit flow control valve (per Patra’s [0050], the flow of the ignition fuel 136 is controllable, i.e., a torch fuel circuit flow control valve is required).
The motivation of the combination of Xuening in view of Patra is the same as the reason as explained for the rejection of claim 1 above.
Regarding claim 8, Xuening further teaches the fuel is a hydrogen-based fuel (hydrogen fuel, see Fig. 1 and [0034]).
Regarding claim 21, Xuening in view of Patra further teaches wherein the start fuel circuit (Xuening’s 110a and 110 in Xuening’s Fig. 2) is connected to a first flow control valve (Xuening’s 150 in Xuening’s Fig. 2), the at least one main fuel circuit (Xuening’s 111a and 111 in Xuening’s Fig. 2) is connected to a second flow control valve (interpreted as the main fuel circuit flow control valve in claim 1, which is Xuening’s 152 in Xuening’s Fig. 2), and the at least one torch fuel circuit (Patra’s torch fuel circuit in order to provide the flow of ignition fuel 136 in Fig. 4, which is a separated fuel circuit from the combustion fuel circuit, see Patra’s [0039 and 0049-0050]) is connected to a third flow control valve (per Patra’s [0050], the flow of the ignition fuel 136 is controllable, i.e., a torch fuel circuit flow control valve is required).
The motivation of the combination of Xuening in view of Patra is the same as the reason as explained for the rejection of claim 1 above.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Xuening 20230050741 in view of Patra 20230304665, and in further view of Dudebout 20130219911.
Regarding claim 2, Xuening in view of Patra does not teach wherein the one or more first zones are located relatively proximal to the ignition source and the one or more second zones are located relatively distal from the ignition source.
However, Dudebout teaches wherein the one or more first zone (associated to injectors 154s in Fig. 4D), which receives a first quantity of the fuel for start-up (the fuel presented as solid line 201 in Figs. 2a, also see Fig. 4D and [0023]), are located relatively proximal to the ignition source (ignitor 160, see Fig. 4D), and the one or more second zones (associated to injectors 156s in Fig. 4D), which receives a second quantity of the fuel in response to a power increasing of the gas turbine (the fuel presented as circle line 202 in Fig. 2a, also see Fig. 4D and [0024-0025]), are located relatively distal from the ignition source (ignitor 160, see Fig. 4D).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to provide Xuening in view of Patra with Dudebout’s placing the ignition source relatively proximal to the one or more first zones (start-up zones) and relatively distal from the one or more second zones (high-power zones) in order to prevent hot-streaking during start-up operation condition (Dudebout, [0005]).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Xuening 20230050741 in view of Patra 20230304665, and in further view of Jarvo 20210108579.
Regarding claim 5, Xuening further teaches wherein the start fuel manifold (110) includes a first arcuate body (the body of 110, see Fig. 2) extending along a first circumferential segment of the combustor (a partial circumference of the combustor 108, see Fig. 2) and the main fuel manifold (111) includes a second arcuate body (the body of 111, see Fig. 2) extending along a second circumferential segment of the combustor (a full circumference of the combustor 108, see Fig. 2), and wherein the start fuel manifold (110) and the main fuel manifold (111) are provided with fuel during different operation modes ([0039]).
Xuening in view of Patra does not teach wherein the first circumferential segment and the second circumferential segment combinedly defines a circumference of the combustor.
However, Jarvo teaches wherein a low power operation fuel manifold (the one of the manifolds 34A and 34B of Fig. 2 that provides fuel during the low power operation condition, see [0050-0052]) includes a first arcuate body (the body of the one of the manifolds 34A and 34B of Fig. 2) extending along a first circumferential segment of the combustor (demonstrated in annotated Fig. 2) and a high power operation fuel manifold (the another one of the manifolds 34A and 34B of Fig. 2 that provides fuel during the high power operation condition, see [0050-0052]) includes a second arcuate body (the body of the another one of the manifolds 34A and 34B of Fig. 2) extending along a second circumferential segment of the combustor (demonstrated in annotated Fig. 2), and wherein the first circumferential segment and the second circumferential segment combinedly defines a circumference of the combustor (see Fig. 2).
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It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to provide Xuening in view of Patra with Jarvo’s two manifold respectively having the first circumferential segment and the second circumferential segment that combinedly defines a circumference of the combustor in order to reduce exposure of fuel manifold to the high combustor temperature and prevent overheat (Jarvo, [0050]).
It is noted that even though Jarvo’s motivation is to prevent soot formation caused by overheating, however, the motivation of shorten fuel manifold to prevent overheating is also applicable to i) gaseous hydrogen fuel in order to control combustion performance and ii) fuel manifold itself in order to reduce thermal stress of the fuel manifold.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Xuening 20230050741 in view of Patra 20230304665 as evidenced by NPL (Miao - Flammability limits of hydrogen-enriched natural gas), refers as Miao thereafter.
Regarding claim 6, Xuening further teaches the fuel (pure gaseous hydrogen fuel, see Fig. 1 and [0034]) has a lower flammability limit relatively lower than a lower flammability limit of a natural gas (as evidenced by Miao, which teaches hydrogen has a lower LFL, i.e., the claimed flower flammability limit, than natural gas; as shown in Table 1, a lager fraction of hydrogen in a mixture of hydrogen and natural gas cases said mixture has a lower LFL, i.e., hydrogen has a lower LFL than natural gas).
Claims 9, 11-12, 22-23, and 25-26 are rejected under 35 U.S.C. 103 as being unpatentable over Xuening 20230050741 in view of Patra 20230304665 and Dudebout 20130219911.
Regarding claim 9, Xuening teaches the invention as claimed: A gas turbine engine (100) comprising: a combustor (108, Figs. 1-2) defining one or more first zones (the zones corresponding to injectors 120a, see Fig. 2) and one or more second zones (the zones corresponding to injectors 120b, see Fig. 2);
a plurality of injectors (comprising injectors 120a and injectors 120b) circumferentially arranged about the combustor (108, see Fig. 2), the plurality of injectors including one or more first injectors (injectors 120a) and one or more second injectors (injectors 120b); and
a system (200, Fig. 2) for delivering a fuel (hydrogen fuel from 124, see Fig. 2 and [0034]), the system comprising:
a start fuel circuit (110a and 110 in Fig. 2, and per [0034, 0039, and 0041], 110 provides fuel to 120a during start-up) configured to be fluidly coupled to the one or more first injectors (120a) to facilitate injection of a first quantity of the fuel (a first quantity of the fuel provided to injectors 120a, [0039]) by the one or more first injectors (120a) into the one or more first zones (the first zones corresponding to injectors 120a, see Fig. 2) for ignition (the flow of the first quantity of fuel is controlled by the flow modulating valve 150 according to operation condition, e.g., start-up and high power, see [0039, 0040, and 0053]);
at least one main fuel circuit (111a and 111 in Fig. 2, and per [0034, 0039, and 0041], 111 provides fuel to 120b during the high power condition) configured to be fluidly coupled to the one or more second injectors (120b) to facilitate injection of a second quantity of the fuel (a second quantity of the fuel provided to injectors 120b, [0039]) by the one or more second injectors (120b) into the one or more second zones (the second zones corresponding to injectors 120b, see Fig. 2; the flow of the second quantity of fuel is controlled by the flow modulating valve 152 according to the operation condition, e.g., start-up and high power, see [0039, 0040, and 0053]) in response to a power increasing of the gas turbine engine ([0039 and 0041]).
Xuening does not teach an ignition source configured to initiate a start-up sequence of the gas turbine engine, and at least one torch fuel circuit configured to be fluidly coupled to the ignition source of the gas turbine engine.
However, Patra teaches a gas turbine engine (10, Fig. 1) comprising an ignition source (torch ignitor 130, see Figs. 4-5A and [0035]) configured to initiate a start-up sequence of the gas turbine engine (by controlling a flow of ignition fuel 136 during start-up, see [0050]), and a system comprising: at least one torch fuel circuit (in order to provide the flow of ignition fuel 136 in Fig. 4, which is a separated fuel circuit from a combustion fuel circuit, see [0039 and 0049-0050]) configured to be fluidly coupled to the ignition source (130) of the gas turbine engine.
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to provide Xuening with Patra’s ignition source configured to initiate a start-up sequence of the gas turbine
engine and at least one torch fuel circuit configured to be fluidly coupled to the ignition source of the gas turbine engine because: comparing to conventional ignitor designed for traditional fuel ignition, Patra’s torch ignitor is designed for hydrogen fuel ignition, especially pure hydrogen (wherein Xuening’s fuel is pure hydrogen as explained above), in order to control the combustion to occur at desired location or to have desired shape (Patra, [0060]).
Xuening in view of Patra does not teach wherein each of the one or more first injectors is located closer to the ignition source than each of the one or more second injectors.
However, Dudebout teaches wherein the ignition source (ignitor 160 in Fig. 4D) is positioned relatively proximate to the one or more first injectors (154s, see Fig. 4D), which receives a first quantity of the fuel for start-up (the fuel presented as solid line 201 in Figs. 2a, also see Fig. 4D and [0023]), and relatively distal from the one or more second injectors (156s, see Fig. 4D), which receives a second quantity of the fuel in response to a power increasing of the gas turbine (the fuel presented as circle line 202 in Fig. 2a, also see Fig. 4D and [0024-0025]).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to provide Xuening in view of Patra with Dudebout’s placing the ignition source relatively proximal to the one or more first injectors and relatively distal from the one or more second injectors, such that
wherein each of the one or more first injectors is located closer to the ignition source than each of the one or more second injectors (the modification to placing Patra’s ignitor proximate to Xuening’s one or more first injectors and relatively distal from Xuening’s one or more second injectors, which read on the claimed limitation, see demonstration in annotated Xuening’s Fig. 2 below)
in order to prevent hot-streaking during start-up operation condition (Dudebout, [0005]).
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Xuening in view of Patra Dudebout does not teach a start fuel circuit configured to facilitate injection of a first quantity of the fuel by the one or more first injectors into one or more first zones upon activation of the ignition source; at least one main fuel circuit configured to facilitate injection of a second quantity of the fuel by the one or more second injectors into one or more second zones in response to a light-off of the first quantity of the fuel, which are functional limitations.
However, it is noted, “apparatus claims, i.e., a system as taught by Xuening in view of Patra Dudebout, cover what a device is, not what a device does. A claim containing a recitation with respect to the manner in which a claimed apparatus is intended to be employed, i.e., … facilitate injection of a first quantity of the fuel … upon activation of the ignition source; … facilitate injection of a second quantity of the fuel … in response to a light-off of the first quantity of the fuel, does not differentiate the claimed apparatus from a prior art apparatus, if the prior art apparatus teaches all the structural limitations of the claim, i.e., as taught by as taught by Xuening in view of Patra Dudebout as discussed above”, MPEP 2114(II). It is noted that the system as taught by Xuening in view of Patra Dudebout is capable of performing the claimed functions.
Regarding claim 11, Xuening further teaches wherein the start fuel circuit (110a and 110, Fig. 2) includes:
a start fuel manifold (110) including an inlet port (where 110a and 110 meet, see Fig. 2) for receiving the fuel into the start fuel manifold (110) and one or more outlet ports (the ports of where 110 connect to injectors 120a, see Fig. 2) for correspondingly supplying the fuel to the one or more first injectors (120a) from the start fuel manifold (110, see [0034, 0039, and 0041]); and
a first flow control valve (150, Fig. 2) fluidly coupled to the inlet port (where 110a and 110 meet, see Fig. 2), the first flow control valve (150) configured to move between a plurality of positions (per [0040], valve 150 may be a variable opening, electrically actuated valve) including a first position (a closed position per [0040]) and a second position (an open position per [0040]), wherein:
at the first position (the closed position), the fuel is restricted to flow towards the inlet port (where 110a and 110 meet, see Fig. 2) and into the start fuel manifold (110; see [0040]), and
at the second position (the open position), the fuel is received into the start fuel manifold (110) by the inlet port (where 110a and 110 meet, see Fig. 2) at a predefined first flow rate (the sufficient fuel flow for start-up that is controlled by valve 150, see [0039-0040 and 0052-0053]) to facilitate the injection of the first quantity of the fuel into the one or more first zones (the zones cooperating to injectors 120a) of the combustor (108).
Regarding claim 12, Xuening further teaches wherein the at least one main fuel circuit (111a and 111) includes:
a main fuel manifold (111) including an inlet opening (where 111a and 111 meet, see Fig. 2) for receiving the fuel into the main fuel manifold (111) and one or more outlet openings (the openings of where 111 connect to the injectors 120b, see Fig. 2) for correspondingly supplying the fuel to the one or more second injectors (injectors 120b) from the main fuel manifold (111, see [0034, 0039, and 0041]); and
a second flow control valve (152, Fig. 2) fluidly coupled to the inlet opening (where 111a and 111 meet, see Fig. 2), the second flow control valve (152) configured to move between a plurality of states (per [0040], valve 152 may be a variable opening, electrically actuated valve) including a first state (the closed state per [0040]) and a second state (the open state per [0040]), wherein:
at the first state (the closed state), the fuel is restricted to flow towards the inlet opening (where 111a and 111 meet, see Fig. 2) and into the main fuel manifold (111; see [0040]), and
at the second state (the open state), the fuel is received into the main fuel manifold (111) by the inlet opening (where 111a and 111 meet, see Fig. 2) at a predefined second flow rate (the fuel flow has a sufficient pressure and velocity that is controlled by valve 152, see [0039-0040 and 0052-0053]) to facilitate the injection of the second quantity of the fuel into the one or more second zones (the zones cooperating to injectors 120b) of the combustor (108).
Regarding claim 22, Xuening in view of Patra and Dudebout further teaches wherein the start fuel circuit (Xuening’s 110a and 110 in Xuening’s Fig. 2) is connected to a first flow control valve (Xuening’s 150 in Xuening’s Fig. 2), the at least one main fuel circuit (Xuening’s 111a and 111 in Xuening’s Fig. 2) is connected to a second flow control valve (Xuening’s 152 in Xuening’s Fig. 2), and the at least one torch fuel circuit (Patra’s torch fuel circuit in order to provide the flow of ignition fuel 136 in Fig. 4, which is a separated fuel circuit from the combustion fuel circuit, see Patra’s [0039 and 0049-0050]) is connected to a third flow control valve (per Patra’s [0050], the flow of the ignition fuel 136 is controllable, i.e., a torch fuel circuit flow control valve is required).
The motivation of the combination of Xuening in view of Patra and Dudebout is the same as the reason as explained for the rejection of claim 9 above.
Regarding claim 23, Xuening teaches the invention as claimed: A system (200, Fig. 2) for delivering a fuel (hydrogen fuel from 124, see Fig. 2 and [0034]) to a gas turbine engine (100, Fig. 1), the gas turbine engine (100) having a combustor (108, Figs. 1-2) and a plurality of injectors (120a and 120b, Fig. 2) circumferentially arranged about the combustor (108, see Fig. 2), the system comprising:
a first fuel circuit (110a and 110 in Fig. 2, and per [0034, 0039, and 0041], 110 provides fuel to 120a during start-up) configured to be fluidly coupled to one or more first injectors (120a) of the plurality of injectors to facilitate injection of a first quantity of the fuel (a first quantity of the fuel provided to injectors 120a, [0039]) by the one or more first injectors (120a) into one or more first zones (the first zones corresponding to injectors 120a, see Fig. 2) of the combustor (108) for ignition (the flow of the first quantity of the fuel is controlled by a flow modulating valve 150 according to the operation condition, e.g., start-up and high power, see [0040 and 0053]);
a second fuel circuit (111a and 111 in Fig. 2, and per [0034, 0039, and 0041], 111 provides fuel to 120b during the high power condition) configured to be fluidly coupled to one or more second injectors (120b) of the plurality of injectors to facilitate injection of a second quantity of the fuel (a second quantity of the fuel provided to injectors 120b, [0039]) by the one or more second injectors (120b) into one or more second zones (the second zones corresponding to injectors 120b, see Fig. 2) of the combustor (118; the flow of the second quantity of the fuel is controlled by a flow modulating valve 152 according to the operation condition, e.g., start-up and high power, see [0040 and 0053]) in response to a power increasing of the gas turbine engine ([0039 and 0041]), and
wherein the first fuel circuit (110a and 110 in Fig. 2) is connected to a first flow control valve (150, Fig. 2), the second fuel circuit (111a and 111 in Fig. 2) is connected to a second flow control valve (152, Fig. 2).
Xuening does not teach an ignition source activated during start-up, and a third fuel circuit configured to be fluidly coupled to the ignition source of the gas turbine engine, and the third fuel circuit is connected to a third flow control valve.
However, Patra teaches a gas turbine engine (10, Fig. 1) comprising an ignition source (torch ignitor 130, see Figs. 4-5A and [0035]) activated during start-up (by controlling a flow of ignition fuel 136 during start-up, see [0050]), and a system comprising: a torch fuel circuit (in order to provide the flow of ignition fuel 136 in Fig. 4, which is a separated fuel circuit from a combustion fuel circuit, see [0039 and 0049-0050]) configured to be fluidly coupled to the ignition source (130) of the gas turbine engine, and the torch fuel circuit is connected to a torch fuel flow control valve (per [0050], the flow of the ignition fuel 136 is controlled, i.e., a torch fuel flow control valve is required).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to provide Xuening with Patra’s ignition source activated during startup, torch fuel circuit configured to be fluidly coupled to the ignition source of the gas turbine engine and being connected to a torch flow control valve, such that
a third fuel circuit configured to be fluidly coupled to the ignition source of the gas turbine engine and the third fuel circuit is connected to a third flow control valve
because: comparing to conventional ignitor designed for traditional fuel ignition, Patra’s torch ignitor is designed for hydrogen fuel ignition, especially pure hydrogen (wherein Xuening’s fuel is pure hydrogen as explained above), in order to control the combustion to occur at desired location or to have desired shape (Patra, [0060]).
Xuening in view of Patra does not teach wherein none of the one or more first injectors is located closer to the ignition source than any of the one or more second injectors.
However, Dudebout teaches wherein the ignition source (ignitor 160 in Fig. 4D) is positioned relatively proximate to the one or more first injectors (154s, see Fig. 4D), which receives a first quantity of the fuel for start-up (the fuel presented as solid line 201 in Figs. 2a, also see Fig. 4D and [0023]), and relatively distal from the one or more second injectors (156s, see Fig. 4D), which receives a second quantity of the fuel in response to a power increasing of the gas turbine (the fuel presented as circle line 202 in Fig. 2a, also see Fig. 4D and [0024-0025]).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to provide Xuening in view of Patra with Dudebout’s placing the ignition source relatively proximal to the one or more first injectors and relatively distal from the one or more second injectors, such that
wherein none of the one or more first injectors is located closer to the ignition source than any of the one or more second injectors (the modification to placing Patra’s ignitor proximate to Xuening’s one or more first injectors and relatively distal from Xuening’s one or more second injectors, which read on the claimed limitation, see demonstration in annotated Xuening’s Fig. 2 below)
in order to prevent hot-streaking during start-up operation condition (Dudebout, [0005]).
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Xuening in view of Patra and Dudebout does not teach a first fuel circuit configured to facilitate injection of a first quantity of the fuel by the one or more first injectors into one or more first zones of the combustor upon activation of an ignition source of the gas turbine engine; a second fuel circuit configured to facilitate injection of a second quantity of the fuel by the one or more second injectors into one or more second zones of the combustor in response to a light-off of the first quantity of the fuel, which are functional limitations.
However, it is noted, “apparatus claims, i.e., a system as taught by Xuening in view of Patra and Dudebout, cover what a device is, not what a device does. A claim containing a recitation with respect to the manner in which a claimed apparatus is intended to be employed, i.e., … facilitate injection of a first quantity of the fuel … upon activation of an ignition source of the gas turbine engine; … facilitate injection of a second quantity of the fuel … in response to a light-off of the first quantity of the fuel, does not differentiate the claimed apparatus from a prior art apparatus, if the prior art apparatus teaches all the structural limitations of the claim, i.e., as taught by as taught by Xuening in view of Patra and Dudebout as discussed above”, MPEP 2114(II). It is noted that the system as taught by Xuening in view of Patra and Dudebout is capable of performing the claimed functions.
Regarding claim 25, Xuening further teaches wherein the first fuel circuit (110a and 110, Fig. 2) includes:
a first fuel manifold (110) including an inlet port (where 110a and 110 meet, see Fig. 2) for receiving the fuel into the first fuel manifold (110) and one or more outlet ports (the ports of where 110 connect to injectors 120a, see Fig. 2) for correspondingly supplying the fuel to the one or more first injectors (120a) from the first fuel manifold (110, see [0034, 0039, and 0041]); and
wherein the first flow control valve (150) is configured to move between a plurality of positions (per [0040], valve 150 may be a variable opening, electrically actuated valve) including a first position (a closed position per [0040]) and a second position (an open position per [0040]), wherein:
at the first position (the closed position), the fuel is restricted to flow towards the inlet port (where 110a and 110 meet, see Fig. 2) and into the first fuel manifold (110; see [0040]), and
at the second position (the open position), the fuel is received into the first fuel manifold (110) by the inlet port (where 110a and 110 meet, see Fig. 2) at a predefined first flow rate (the sufficient fuel flow for start-up that is controlled by valve 150, see [0039-0040 and 0052-0053]) to facilitate the injection of the first quantity of the fuel into the one or more first zones (the zones cooperating to injectors 120a) of the combustor (108).
Regarding claim 26, Xuening further teaches wherein the second fuel circuit (111a and 111) includes
a second fuel manifold (111) including an inlet opening (where 111a and 111 meet, see Fig. 2) for receiving the fuel into the second fuel manifold (111) and one or more outlet openings (the openings of where 111 connect to the injectors 120b, see Fig. 2) for correspondingly supplying the fuel to the one or more second injectors (injectors 120b) from the second fuel manifold (111, see [0034, 0039, and 0041]); and
wherein the second flow control valve (152) is configured to move between a plurality of states (per [0040], valve 152 may be a variable opening, electrically actuated valve) including a first state (the closed state per [0040]) and a second state (the open state per [0040]), wherein:
at the first state (the closed state), the fuel is restricted to flow towards the inlet opening (where 111a and 111 meet, see Fig. 2) and into the second fuel manifold (111; see [0040]), and
at the second state (the open state), the fuel is received into the second fuel manifold (111) by the inlet opening (where 111a and 111 meet, see Fig. 2) at a predefined second flow rate (the fuel flow has a sufficient pressure and velocity that is controlled by valve 152, see [0039-0040 and 0052-0053]) to facilitate the injection of the second quantity of the fuel into the one or more second zones (the zones cooperating to injectors 120b) of the combustor (108).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Xuening 20230050741 in view of Patra 20230304665 and Dudebout 20130219911, and in further view of Jarvo 20210108579.
Regarding claim 13, Xuening further teaches wherein the start fuel manifold (110) includes a first arcuate body (the body of 110, see Fig. 2) extending along a first circumferential segment of the combustor (a partial circumference of the combustor 108, see Fig. 2) and the main fuel manifold (111) includes a second arcuate body (the body of 111, see Fig. 2) extending along a second circumferential segment of the combustor (a full circumference of the combustor 108, see Fig. 2), and wherein the start fuel manifold (110) and the main fuel manifold (111) are provided with fuel during different operation modes ([0039]).
Xuening in view of Patra and Dudebout does not teach wherein the first circumferential segment and the second circumferential segment combinedly defines a circumference of the combustor.
However, Jarvo teaches wherein a low power operation fuel manifold (the one of the manifolds 34A and 34B of Fig. 2 that provides fuel during the low power operation condition, see [0050-0052]) includes a first arcuate body (the body of the one of the manifolds 34A and 34B of Fig. 2) extending along a first circumferential segment of the combustor (demonstrated in annotated Fig. 2) and a high power operation fuel manifold (the another one of the manifolds 34A and 34B of Fig. 2 that provides fuel during the high power operation condition, see [0050-0052]) includes a second arcuate body (the body of the another one of the manifolds 34A and 34B of Fig. 2) extending along a second circumferential segment of the combustor (demonstrated in annotated Fig. 2), and wherein the first circumferential segment and the second circumferential segment combinedly defines a circumference of the combustor (see Fig. 2).
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It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to provide Xuening in view of Patra and Dudebout with Jarvo’s two manifold respectively having the first circumferential segment and the second circumferential segment that combinedly defines a circumference of the combustor in order to reduce exposure of fuel manifold to the high combustor temperature and prevent overheat (Jarvo, [0050]).
It is noted that even though Jarvo’s motivation is to prevent soot formation caused by overheating, however, the motivation of shorten fuel manifold to prevent overheating is also applicable to i) gaseous hydrogen fuel in order to control combustion performance and ii) fuel manifold itself in order to reduce thermal stress of the fuel manifold.
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Xuening 20230050741 in view of Patra 20230304665 and Dudebout 20130219911, as evidenced by NPL (Miao - Flammability limits of hydrogen-enriched natural gas), refers as Miao thereafter.
Regarding claim 14, Xuening in view of Patra and Dudebout further teaches wherein the fuel (Xuening’s hydrogen per Xuening’s [0034]) has a lower flammability limit relatively lower than a lower flammability limit of a natural gas (as evidenced by Miao, which teaches hydrogen has a lower LFL, i.e., the claimed flower flammability limit, than natural gas; as shown in Table 1, a lager fraction of hydrogen in a mixture of hydrogen and natural gas cases said mixture has a lower LFL, i.e., hydrogen has a lower LFL than natural gas), and
wherein the first quantity of the fuel (Xuening’s first quantity of the fuel provided to Xuening’s injector 120a for start-up, see Xuening’s [0039]) is injected and ignited (per Xuening’s [0053]) by the ignition source (Patra’s ignitor 130 in Patra’s Fig. 4) while the injection of the second quantity of the fuel (Xuening’s second quantity of the fuel provided to Xuening’s injectors 120b for the high power condition, see Xuening’s [0039]) is restricted (per Xuening’s [0041], during startup, Xuening’s second fuel flow valve 152 remains closed), and
wherein the start fuel circuit (Xuening’s 110a and 110 in Xuening’s Fig. 2) is connected to a first flow control valve (Xuening’s 150 in Xuening’s Fig. 2), the at least one main fuel circuit (Xuening’s 111a and 111 in Xuening’s Fig. 2) is connected to a second flow control valve (Xuening’s 152 in Xuening’s Fig. 2), and the at least one torch fuel circuit (Patra’s torch fuel circuit in order to provide the flow of ignition fuel 136 in Fig. 4, which is a separated fuel circuit from the combustion fuel circuit, see Patra’s [0039 and 0049-0050]) is connected to a third flow control valve (per Patra’s [0050], the flow of the ignition fuel 136 is controllable, i.e., a torch fuel circuit flow control valve is required).
The motivation of the combination of Xuening in view of Patra and Dudebout is the same as the reason as explained for the rejection of claim 9 above.
Xuening in view of Patra and Dudebout as evidence by Miao does not teach wherein the first quantity of the fuel is injected upon the activation of the ignition source while the injection of the second quantity of the fuel is restricted to maintain a concentration of the fuel in a fuel-air mixture downstream of the combustor below the lower flammability limit of the fuel, which are functional limitations.
However, it is noted, “apparatus claims, i.e., a system as taught Xuening in view of Patra and Dudebout as evidenced by Miao, cover what a device is, not what a device does. A claim containing a recitation with respect to the manner in which a claimed apparatus is intended to be employed, i.e., … is injected upon the activation of the ignition source; … to maintain a concentration of the fuel in a fuel-air mixture downstream of the combustor below a lower flammability limit of the fuel, does not differentiate the claimed apparatus from a prior art apparatus, if the prior art apparatus teaches all the structural limitations of the claim, i.e., as taught by as taught by Xuening in view of Patra and Dudebout as discussed above”, MPEP 2114(II). It is noted that the system as taught by Xuening in view of Patra and Dudebout as evidenced by Miao is capable of performing the claimed functions.
Response to Arguments
Applicant's arguments filed 02/26/2026 have been fully considered.
Regarding the functional limitations of claim 1, Applicant argues, on pp. 13-14, “Applicant disagrees with this interpretation of the claims' recitations of "configured." As MPEP 2114(1) states, "[f]eatures of an apparatus may be recited either structurally or functionally." Citation omitted. The Federal Circuit discussed the interpretation of the claim recitation "configured," in a number of court cases. For example, the Federal Circuit has stated that "configured to" "mean[s] 'made to' or 'designed to."' In re Gianelli, 739 F.3d 1375, 1379 (Fed. Cir 2014); see also e.g., Aspex Eyewear, Inc. v. Marchan Eyewear, Inc., 672 F.3d 1335, 1349 (Fed. Cir. 2012). … No reference of record discloses or suggests such a valve as specifically claimed. For example, no reference discloses or suggests a valve that is configured to restrict flow to maintain a fuel concentration downstream of a combustor as specifically claimed, upon activation of an ignition source. This is at least because there is no disclosure of any such valve in any of the applied references, which "upon the activation of the ignition source" "restrict[s] flow to maintain a fuel concentration downstream of the combustor'' as further claimed. Thus, any rejection would not be based on any disclosure in any of the references, but instead would be without any evidentiary basis in the record”.
Examiner does not agree because: it is noted that Features of an apparatus may be recited either structurally or functionally. In re Schreiber, 128 F.3d 1473, 1478, 44 USPQ2d 1429, 1432 (Fed. Cir. 1997). See also MPEP § 2173.05(g). If an examiner concludes that a functional limitation is an inherent characteristic of the prior art, then to establish a prima case of anticipation or obviousness, the examiner should explain that the prior art structure inherently possesses the functionally defined limitations of the claimed apparatus. In re Schreiber, 128 F.3d at 1478, 44 USPQ2d at 1432. See also Bettcher Industries, Inc. v. Bunzl USA, Inc., 661 F.3d 629, 639-40, 100 USPQ2d 1433, 1440 (Fed. Cir. 2011). The burden then shifts to applicant to establish that the prior art does not possess the characteristic relied on. In re Schreiber, 128 F.3d at 1478, 44 USPQ2d at 1432; In re Swinehart, 439 F.2d 210, 213, 169 USPQ 226, 228 (CCPA 1971) (“where the Patent Office has reason to believe that a functional limitation asserted to be critical for establishing novelty in the claimed subject matter may, in fact, be an inherent characteristic of the prior art, it possesses the authority to require the applicant to prove that the subject matter shown to be in the prior art does not possess the characteristic relied on”), MPEP 2114(I), in this case, the functions as claimed in claim 1 is respectively modulating the first quantity of the fuel, the second quantity of the fuel, and the flow of ignition fuel during different operation conditions via a respective flow control valve, and Examiner explained that the system of Xuening in view of Patra is capable of performing said claimed functions because three respective flow control valves that is capable of respectively modulating the first quantity of the fuel, the second quantity of the fuel, and the flow of ignition fuel are taught by Xuening in view of Patra, i.e., Xuening’s flow modulating valve 150, Xuening’s flow modulating valve 152, and Patra’s torch fuel control valve per Patra’s [0050] (see rejection above).
Regarding the art rejection of claims 9 and 23, the combination of Xuening in view of Patra and Dudebout still teaches the amended limitation because:
i) the base reference Xuening teaches a plurality of start-up fuel injectors 120a that are continuously arranged in a circumferential direction of the combustor 108, see Fig. 2, and a plurality of main fuel injectors 120b that are continuously arranged in the circumferential direction of the combustor 108, see Fig. 2, i.e., none of the plurality of start-up fuel injectors 120a is arrange between the plurality of main fuel injectors 120b;
ii) Dudebout teaches an ignitor is placing at a location closer to the start-up fuel injectors 154 comparing to the main fuel injectors 156, see Fig. 4D, for the motivation as explained in the rejection, see above;
iii) even though Dudebout’s main fuel injectors 156 are arranged between Dudebout’s start-up fuel injectors 154 as shown in Fig. 4D, the modification of Xuening in view of Patra and Dudebout is to place Patra’s ignitor 160 to a location closer to Xuening’s start-up fuel injector 120a comparing to Xuening’s main fuel injectors 120b, which is a location in the area marked in Xuening’s annotated Fig. 2, see above, and thus, the combination of Xuening in view of Patra and Dudebout reads on the amended limitations.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Kirzhner 20120036863 teaches a method of modulating a flow rate of fuel provided to a combustor according to different operation condition that includes start-up, wherein the flow rate of fuel is set according to the lower flammability of the fuel in order to prevent lean blow out and risk of explosion.
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/JINGCHEN LIU/Examiner, Art Unit 3741
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