DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Status of Claims
2. Claims 1-18 are pending in this application and examined herein.
Response to Arguments
3. The response dated 06/29/26 overcomes the drawing objections and the claim rejections under 35 U.S.C. 112.
4. Regarding the claim rejections under 35 U.S.C. 103, Applicant's arguments filed 06/29/26 have been fully considered but they are not persuasive. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). In the proposed rejection, the PCM-containing cooling system of Austin is combined with the nuclear reactor system of Gauthe. In the proposed combination, the system of Autin is arranged around the existing structure of Gauthe, thereby forming the claimed space delimited between the shell (of Gauthe) and the secondary vessel (of Austin).
5. The response of 06/29/26 does not address the double patenting rejections. As a reminder, double patenting rejections cannot be held in abeyance. MPEP 804(I)(B)(1). Further responses not addressing this issue will be deemed noncompliant.
Information Disclosure Statement
6. The listing of references in the specification is not a proper information disclosure statement. 37 CFR 1.98(b) requires a list of all patents, publications, or other information submitted for consideration by the Office, and MPEP § 609.04(a) states, "the list may not be incorporated into the specification but must be submitted in a separate paper." Therefore, unless the references have been cited by the examiner on form PTO-892, they have not been considered.
Claim Rejections - 35 USC § 103
7. 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.
8. For applicant's benefit, the portions of the reference(s) relied upon in the below rejections have been cited to aid in the review of the rejections. While every attempt has been made to be thorough and consistent within the rejection, it is noted that prior art must be considered in its entirety, including disclosures that teach away from the claims. See MPEP 2141.02 VI.
9. 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.
10. Claims 1-5, 7-14, 16, and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Gauthe et al., US 2021/0210229 in view of Austin, et a., GB 2 263 188.
11. Regarding claim 1, Gauthe discloses a nuclear reactor cooled by liquid metal ([0076]), comprising:
a primary vessel (10) axisymmetric about a central axis filled with a first coolant, the first coolant being a liquid metal ([0084]), comprising:
a core (11) made up of assemblies (110) containing nuclear fuel materials in the solid state, contained in at least one barrel (see Fig. 4 and the NRC glossary definitions of fuel assembly and fuel rod);
a structure forming a redan (16), with a central axis coincident with the central axis of the primary vessel, the structure being arranged in the primary vessel so as to separate an inside thereof into a central zone and a peripheral zone so that during operation of the reactor, the first coolant circulates by natural convection, in a loop from a bottom of the central zone in which the core inside which fission reactions occur, rises by heating to a top of the central zone, diverted towards a top of the peripheral zone to descend towards a bottom of the peripheral zone, where it is diverted towards the core of the reactor ([0088], [0090]);
a secondary vessel (32) arranged around the primary vessel;
a core head plug (14) configured to enclose the first coolant inside the primary vessel ([0085]); and
a system for removing heat generated by the reactor both during nominal operation and in situations in which the nuclear reactor is shut down ([0101]), the system comprising:
a shell (32) arranged between the primary vessel and the secondary vessel, defining a volume between the shell and the primary vessel filled with a liquid metal bath ([0084]); and
a closed secondary circuit (400) filled with a second coolant, the closed secondary circuit capable of removing the heat generated by the reactor by conduction through the primary vessel and transferred by the liquid metal ([0102-7]).
Gauthe does not disclose a second heat removal system comprising a phase change material. Austin teaches a liquid metal cooled nuclear reactor (see Fig. 1 and p. 1) comprising a primary vessel (1) axisymmetric about a central axis, filled with a first liquid metal coolant;
a secondary vessel (3), arranged around the primary vessel;
a reactor pit (7); arranged around the secondary vessel;
a system for removing decay heat in accident situations of the nuclear reactor, the system comprising: at least one solid-liquid phase-change material (PCM) arranged inside a space delimited between the primary and secondary vessels (p. 4), the PCM(s) being capable of melting while storing by latent heat at least some of the decay heat emitted by the core in accident situations, for a predetermined duration (p.4).
One of ordinary skill in the art at the time of the invention/filing would have found it obvious to combine the heat removal system of Austin with the reactor of Gauthe for the predictable purpose of “increasing transfer of heat through the space” surrounding the secondary vessel of Gauthe (see Austin at p. 1).
12. Regarding claim 3, Gauthe as modified by Austin makes claim 1 obvious. Gauthe further discloses the primary vessel and the shell being concentric right cylinders (Fig. 4), while Austin further teaches the primary and secondary vessels being right cylinders arranged concentrically with each other. It would therefore have been an obvious matter of design choice to change the chape of Gauthe’s secondary vessel to be a cylinder.
13. Claims 4 and 17 further limit an alternative limitation of claim 1. Because Gauthe discloses the other alternative, these claims are not addressed further on the basis of prior art.
14. Regarding claim 5, Gauthe as modified by Austin makes claim 1 obvious. Gauthe further discloses a reactor wherein the closed secondary circuit comprises a serpentine coil (42) arranged between the primary vessel and the shell in a spiral around the shell (Fig. 3, [0117])
15. Regarding claims 7 and 8, Gauthe as modified by Austin makes claim 1 obvious. Austin further discloses that the phase change material is a power of aluminum (see pp. 3-4). One of ordinary skill in the art at the time of the invention/filing would have found it obvious to combine the heat removal system of Austin with the reactor of Gauthe for the reason stated above.
16. Regarding claims 9 and 10, Gauthe as modified by Austin makes claim 1 obvious. Gauthe further discloses the primary vessel and the shell being made of AISI 316L stainless steel ([0084], [0099]). Austin is silent as to the material of its secondary vessel. However, it would be reasonable to assume that it is made of a heat conducting metal so as to transfer heat to the phase change material between the secondary vessel and the reactor pit (p.4). Accordingly, a skilled artisan would have found it obvious to select the AISI 316L stainless steel of Gauthe for all of the vessels on the combination with Austin. It has been held to be within the general skill of a worker in the art to select known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 125 USPQ 416.
17. Regarding claims 11 and 12, Gauthe as modified by Austin makes claim 1 obvious. Gauthe further discloses a nuclear reactor wherein the primary vessel is devoid of moderating material so that the reactor operates using fast neutrons ([0001] “fast”). Regarding claim 12, thermal sodium graphite reactors are known, so it would have been obvious to apply the cooling systems taught by Gauthe and Austin to such reactors to obtain the same emergency cooling capabilities in a thermal sodium-cooled nuclear reactor.
18. Regarding claims 13 and 14, Gauthe as modified by Austin makes claim 1 obvious. Gauthe further discloses a reactor wherein the solid nuclear fuels are nuclear fuel assemblies ([0077]), but is silent as to the type of fuel in the fuel assemblies. However low enriched UO2 fuels are ubiquitous in the art and therefore would have been an obvious choice in the reactor of Gauthe (see the NRC glossary definitions of fuel assembly, fuel rod and fuel pellet).
19. Regarding claim 16, Gauthe as modified by Austin makes claim 1 obvious. Gauthe does not disclose a less than 20 MWth reactor ([0003]). However, it would have been obvious to apply the cooling systems taught by Gauthe and Austin to such a reactor to obtain the same emergency cooling capabilities.
20. Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Gauthe et al., US 2021/0210229 in view of Austin, et a., GB 2 263 188 in further view of Hunsbedt et al, US 5,021,211.
21. Regarding claim 15, Gauthe as modified by Austin makes claim 1 obvious. Gauthe suggests the presence of a reactivity control system ([0006]), but is silent as to its details. Hunsbedt teaches a liquid metal cooled nuclear reactor having a reactivity control system comprising control rods inside the primary vessel (column 4, lines 36-38). One of ordinary skill in the art at the time of invention/filing would have found it obvious to combine such control rods with the reactor of Gauthe for the predictable purpose of “ control[ing] the fission activity and rate of the fuel of the core and in turn production of thermal energy (column 4, lines 3-40).
22. Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over Gauthe et al., US 2021/0210229 in view of Austin, et a., GB 2 263 188 in further view of Jackson US, 3,888,730.
23. Regarding claim 18, Gauthe as modified by Austin makes claim 1 obvious. Gauthe does not disclose fins on the heat exchange tubes of its secondary circuit. Jackson teaches a heat exchange circuit for a liquid metal cooled nuclear reactor, the heat exchange tubes having fins on their periphery (column 3, lines 43-50). One of ordinary skill in the art at the time of invention/filing would have found it obvious to combine the fins taught by Jackson to the cooling system of Gautier because it is well-known in the art of heat exchangers that fins provide increased surface area, thereby increasing heat transfer between media.
Allowable Subject Matter
24. Claims 2 and 6 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
Double Patenting
25. The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
26. A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP §§ 706.02(l)(1) - 706.02(l)(3) for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
27. The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/process/file/efs/guidance/eTD-info-I.jsp.
28. Claims 1-18 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-19 of copending Application No. 18593478 (reference application). This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Although the claims at issue are not identical, they are not patentably distinct from each other because claim 1 of the reference application anticipates instant claim 1. The dependent claims of the reference application anticipate the dependent claims of the instant application.
Finality
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Interviews
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.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SHARON M DAVIS whose telephone number is (571)272-6882. The examiner can normally be reached Monday - Thursday, 7:00 - 5:00 pm ET.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jack Keith can be reached at 571-272-6878. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/SHARON M DAVIS/Primary Examiner, Art Unit 3646
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