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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 12/18/2025 has been entered.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 1-2, 4-7, 9-17 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 1, line 9 and claim 11, line 8 recites “a circumferentially closed ring free from flow-dividing partitions” which is considered new matter. The claim limitation “free from flow-dividing partitions” is considered a negative limitation which does not have basis in the original disclosure, so that the claim limitation fails to meet the written description requirement, see MPEP 2173.05(i). Furthermore, Figure 3 dated 5/4/2016 has a flow dividing partitions at 305 and Figure 9 dated 12/13/2023 of the instant application has a flow dividing partitions due to 610 and 614, so that this claim limitations fails to meet the written description requirement.
Claims dependent thereon are rejected for the same reasons.
Allowable Subject Matter
Claim 20 is allowed.
Response to Arguments
Applicant's arguments filed 12/18/2025 have been fully considered but they are not persuasive.
Applicant asserts that Dahm does not have a single annular duct because there is not flow between the innermost surface 26 of rotor 24 and the outward surface 14 of the stator 12 of Dahm. Examiner respectfully disagrees. Even if there is no flow between the innermost surface 26 of rotor 24 and the outward surface 14 of the stator 12of Dahm, Annotated Figure 4; labeled cross-section of Dahm still forms a single annular duct because the working fluid still flows at least partially through the annular duct of Dahm.
Applicant asserts that one of ordinary skill would not modify Dahm with Bunker because it requires substantial reconstruction and redesign. Examiner respectfully disagrees. The modification of Bunker in Dahm makes the single annular duct of Dahm axisymmetric. In particular, the modification moves Figure 2; 62, 56 of Dahm to make the single annular duct of Dahm axisymmetric. Applicant asserts that making the single annular duct of Dahm axisymmetric requires removing channel walls/partitions. Examiner respectfully disagrees. An object, such as a regular pentagram star, is axisymmetric so long as the points of the regular pentagram star are equally spaced apart along 360 degrees. Figure 3- 7 of Dahm show that the channel walls/partitions are equally spaced apart along 360 degrees, so that the single annular duct of Dahm is axisymmetric.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Bunker et al (US 20100282721 as referenced in OA dated 6/18/2025) states in Paragraph 0016 that a gas turbine engine is axisymmetrical
Broomer et al (US 20100266386 as referenced in OA dated 6/18/2025) states in Paragraph 0024 that a gas turbine engine is axisymmetrical
Trefny et al (US 20150013305 as referenced in OA dated 6/13/2023) shows in Figure 4 of fuel injectors penetrating into an annular duct, so that the annular duct does not form a circumferentially closed ring along an entire extent
Curran (US 3667233 as referenced in OA dated 6/13/2023) shows in Figure 4 of fuel injectors penetrating into an annular duct, so that the annular duct does not form a circumferentially closed ring along an entire extent
Hamed et al (Flow Separation in Shock Wave Boundary Layer Interactions as referenced in OA dated 9/4/2018) states in the Introduction “Shock boundary layer interactions are usually the cause of flow separation at hypersonic and supersonic speeds.”
Ramgen Power Systems (as referenced in OA dated 9/4/2018) states “At supersonic velocities, air is ingested into the engine and flows around a fixed obstructing body in the center of the engine duct, "ramming" the air flow into channels between the center-body and the engine's sidewall. Inside these channels, the airflow is almost instantaneously slowed to subsonic speeds, creating "shock waves." These shock waves are associated with a dramatic increase in pressure, or, in other words, "shock compression."”
Neubrand et al (US 20150345297 as referenced in OA dated 11/4/2020) in Figure 3a shows a blade
Marini et al (US 8092178 as referenced in OA dated 11/4/2020) shows a blade as Figure 2, 24.
Nuvotny (US 5135354 as referenced in OA dated 11/4/2020) shows a blade as Figure 2, 22.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to EDWIN G KANG whose telephone number is (571)272-9814. The examiner can normally be reached Mon-Fri 8:00-5:00 PM EST.
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/EDWIN KANG/Primary Examiner, Art Unit 3741