DETAILED ACTION
This is a non-final rejection in response to application filed 3/3/25. Claims 1-10 are currently pending.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
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.
Claim(s) 1-6 and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mantchenkov et al. (US 2006/0059914) in view of York et al. (US 2010/0212322), and further in view of Herbon et al. (US 2012/0144832).
Regarding independent claim 1 and 6, Mantchenkov teaches an injection device, for a combustion chamber of a turbine of an aircraft turbine engine [0025], characterized in that it comprises, about a longitudinal axis, a tubular central channel 4, a first annular channel 8 about the central channel, the channels being configured so as to be open to the combustion chamber at a first lip of the central channel [0026], at a second lip of the first annular channel [0027], the first annular channel comprising, upstream of the second lip [0027], means for injecting (fuel feed channels 10) into the first annular channel in an air flow moving along the longitudinal axis of the first annular channel [0028].
Mantchenkov is silent to the injection device for injecting a combustible air-dihydrogen mixture
and a second annular channel about the first annular channel, the channels being configured so as to be open to the combustion chamber at an end of the second annular channel, means for injecting dihydrogen into the first annular channel in an air flow moving along the longitudinal axis of the first annular channel so as to produce a dihydrogen-air mixture flowing between the first lip and the second lip.
York teaches the injection device for injecting a combustible air-dihydrogen mixture [0025-0026] and a second annular channel 23 about the first annular channel, the channels being configured so as to be open to the combustion chamber at an end of the second annular channel [0021], means for injecting dihydrogen into the first annular channel in an air flow moving along the longitudinal axis of the first annular channel so as to produce a dihydrogen-air mixture flowing between the first lip and the second lip [0021-0022].
Herbon teaches the first annular channel comprising, upstream of the second lip, means for injecting dihydrogen into the first annular channel in an air flow moving along the longitudinal axis of the first annular channel so as to produce a dihydrogen-air mixture flowing between the first lip and the second lip ([0026], fluid conduits 14 connect upstream portion of the fuel passage 20 to air passages 18 such that air mixes with the fuel wint ht the fuel passage itself upstream of the injection orifice).
It would have been obvious to one of ordinary skill in the art at the time of filing to modify Mantchenkov’s aircraft turbomachine coaxial injector structure by adding York’s second annular air passage to obtain the claimed three channel geometry and to further combine Mantchenkov in view of York with the fuel-carrying channel as taught by Herbon as part of an obvious combination of known prior art structures, to achieve predictable results, in this case, a three-channel dihydrogen-air premixing device for an aircraft gas turbine engine. See KSR; MPEP 2141 III A.
Regarding dependent claim 2, Mantchenkov in view of York and Herbon teaches the invention as claimed and discussed above. Mantchenkov further teaches wherein the first lip is arranged upstream of the end of the second annular channel [0027], the central channel 6, 6’ being open to the combustion chamber at the first lip, upstream of the end of the second annular channel, and/or wherein the second lip is arranged upstream of the end of the second annular channel, the first annular channel being open to the combustion chamber at the second lip, upstream of the end of the second annular channel. Mantchenkov as combined with York teaches air feed channel opens into tubular structure [0026], York’s outer air passage 23 provides the second annular channel and its end/opening [0021]. The staggered opening relationship is applied to position the central channel’s opening upstream of the second annular channel’s end [0026-0027].
Regarding dependent claim 3, Mantchenkov in view of York and Herbon teaches the invention as claimed and discussed above. York further teaches wherein the central channel is provided with a first swirler 38 for rotating a gas passing through it [0029].
Regarding dependent claim 4, Mantchenkov in view of York and Herbon teaches the invention as claimed and discussed above. York further teaches wherein the second annular channel 23 is provided with a second swirler 38 for rotating the gas passing through it.
Regarding dependent claim 5, Mantchenkov in view of York and Herbon teaches the invention as claimed and discussed above. Mantchenkov as combined further teaches wherein said means for injecting dihydrogen comprise a plurality of first conduits [0029] between an external wall of said first annular channel and an annular pipe 20 for supplying said conduits, said annular pipe being supplied by one or more second conduits that bring in dihydrogen.
Regarding dependent claim 9, Mantchenkov in view of York and Herbon teaches the invention as claimed and discussed above. York further teaches wherein, said injection device comprising a first swirler in the tubular central channel, the air is rotated in the central channel by said first swirler, and/or wherein, said injection device comprising a second swirler in the second annular channel, the air is rotated in the second annular channel [0029].
Claim(s) 7-8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mantchenkov in view of York and Herbon, and further in view of Koizumi et al. (US 2007/0003897).
Regarding dependent claim 7, Mantchenkov in view of York and Herbon teaches the invention as claimed and discussed above. Mantchenkov in view of York and Herbon is silent to wherein the dihydrogen-air premix has a dihydrogen richness that is greater than two.
Koizumi teaches a burner injecting a mixed gas fuel containing hydrogen into the combustion chamber, the relationship between fuel/air mass flow ratio and adiabatic flame temperature for a hydrogen-containing fuel, the adiabatic flame temperature rises as A/F increases, reaches a maximum at stoichiometric and falls as F/A is increased further into fuel-rich region [0050-0051]. Kpoizumi further teaches that operating with an enriched fuel concentration is a deliberate design technique for reducing flame temperature [0056].
In view of the prior art teachings, tuning the richness of the dihydrogen-air premix is a result effective variable, it would have been obvious to one of ordinary skill in the art at the time of the invention to modify the A/F ratio in Mantchenkov in view of York and Herbon, since it has been held that optimizing a result effective variable was an obvious extension of prior art teachings, In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977), In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955),“[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” MPEP 2144.05 I and II.
Regarding dependent claim 8, Mantchenkov in view of York and Herbon and further in view of Koizumi teaches the invention as claimed and discussed above. Mantchenkov in view of York and Herbon and further in view of Koizumi, wherein the injection of air into the tubular central channel and into the second annular channel is an injection of pure air, targeting an overall injection richness of between 0.3 and 0.5. See claim 7 above.
Allowable Subject Matter
Claim 10 objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CRAIG SANG KIM whose telephone number is (571)270-1418. The examiner can normally be reached 7:00 AM - 3:00 PM.
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/CRAIG KIM/
Primary Examiner
Art Unit 3741
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