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 .
Election/Restrictions
Applicant's election with traverse of claims 1-13 in the reply filed on 3/30/2026 is acknowledged. Claims 14–20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. The traversal is on the ground(s) that there is no serious burden. This is not found persuasive because there would be a serious search and/or examination burden if restriction were not required because one or more of the following reasons apply:
a. The inventions have acquired a separate status in the art in view of their different classification;
b. The inventions have acquired a separate status in the art due to their recognized divergent subject matter;
c. The inventions require a different field of search (for example, searching different classes/subclasses or electronic resources, or employing different search queries);
d. The prior art applicable to one invention would not likely be applicable to another invention;
e. The inventions are likely to raise different non-prior art issues under 35 U.S.C. 101 and/or 35 U.S.C. 112(a).
The requirement is still deemed proper and is therefore made FINAL.
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.
For Applicant’s benefit, portions of the cited reference(s) have been cited to aid in the review of the rejection(s). While every attempt has been made to be thorough and consistent within the rejection, it is noted that the prior art must be considered in its entirety, including disclosures that teach away from the claims. See MPEP 2141.02 VI.
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 of this title, 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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1–4, 6–10, and 12–13 are rejected under 35 U.S.C. 103 as being unpatentable over Gou (US 5,577,085) in view of Isberg (US 3,712,851).
Regarding claim 1, Gou discloses (fig. 1 with the modification of the inclusion of shell 60, fig. 7) a small nuclear reactor plant for modular power demands of approximately 300 Megawatt-electric, the plant comprising: a boiling water nuclear reactor (see title; shown in fig. 1) including a pressure vessel (60, lid 6) having a height-to-width ratio; a containment structure (2, 4) surrounding the nuclear reactor and closed by a top shield (12); a primary coolant loop (28[Wingdings font/0xE0]30) passing through the containment structure and connecting to the nuclear reactor pressure vessel to provide commercial energy extraction from the reactor; and an emergency coolant loop (“emergency core cooling lines,” col. 4, l. 57) passing through the containment structure and connecting to the nuclear reactor pressure vessel to provide shutdown energy extraction from the reactor (“isolation condensers will remove the long-term decay heat,” col. 2, ll. 56-57).
Gou does not explicitly state height-to-width ratio is at least 3.9 or that the containment structure and nuclear reactor extend underground.
Isberg does. Isberg is in the same art area of boiling water nuclear reactors and teaches a small nuclear reactor (fig. 2a) for modular power demands of approximately 300 Megawatt-electric (400 MW, table 1) having a pressure vessel (2) with a height-to-width ratio of at least 3.9 (FIG. 2a appears to show a ratio of about 5) wherein the containment structure and nuclear reactor extend underground (the entire reactor is underground, as shown in fig. 2a).
The combination of the elongate and subterranean nature of Isberg with the reactor of Gou would have produced an underground elongate boiling water reactor with primary and emergency cooling, i.e., Applicant's claimed invention.
This combination would have been obvious to one having ordinary skill in the art before the effective filing date of the invention, as it produces no unexpected results. In view of the prior art teachings of Gou, a person of ordinary skill would have predicted that combining Isberg’s elongate and subterranean features with Gou's reactor would have produced Applicant's claimed invention of a buried, elongated BWR with cooling loops.
The skilled person’s motivation for installing the reactor underground would have been the expectation of greater leakage protection, as noted by Isberg in col. 1, ll. 50-70 and col. 2, ll. 67-75; Examiner further notes that underground installations inherently offer vastly improved protection against incoming missiles compared to their above-ground counterparts.
The skilled person’s motivation for having a particularly elongate shape of reactor vessel (H:W ratio ≥ 3.9) would have been the obvious benefit of a greater surface area available for cooling by the surrounding ground. A tall, lidded coffee cup loses heat quicker than a short one. Examiner notes that, similar to the underground benefit, a more elongated vessel will offer greater protection against leakage and missile strikes because the most radioactive portion—the core—is near the bottom of the reactor and would be farther from the ground surface.
Moreover, it would have been an obvious matter of design choice to have a long cylindrical shape, since such a modification would have involved a mere increase in elongation of an already elongated component. A change in size or shape is generally recognized as being within the level of ordinary skill in the art.
Regarding claim 2, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses wherein the containment structure lacks an emergency reservoir of coolant flowing into the reactor (“Other emergency core cooling systems are not needed,” col. 3, ll. 1-2).
Regarding claim 3, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses wherein the containment structure includes a plurality of seals each at a penetration (col. 2, ll. 28-31) of the containment structure.
Regarding claim 4, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses wherein the containment structure and seals are configured to maintain a pressure up to an operating pressure of the reactor without leakage (this is true of all commercial nuclear reactors, including Gou’s—nuclear reactors are designed to operate at operating pressure without leaking).
Regarding claim 6, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses wherein the emergency coolant loop includes an isolation condenser outside the containment structure (“isolation condensers will remove the long-term decay heat,” col. 2, ll. 56-57; the lines that lead to them are in the upper portion of the containment, col. 4, ll. 56-58) configured to provide emergency cooling to the reactor for multiple days (this capability is implicit, as the isolation condensers are the only form of decay heat removal; the ordinary skilled artisan would understand that several days at a minimum would be needed for cooling).
Regarding claim 7, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Isberg discloses a silo (21) housing the containment structure (9) and reactor (2) underground, wherein the silo seismically isolates the reactor. The skilled artisan would have been motivated, prior to the effective filing date of the invention, to have utilized Isberg’s silo to “take up shock forces on the occurrence of an accident,” as explained in col. 4, ll. 30-32, and to “form a secondary containment for gases which may leak,” col. 10, ll. 7-13.
Regarding claim 8, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses a plurality of isolation valves (26) at each connection of the reactor and the primary and emergency coolant loops (col. 2, ll. 28-31; e.g., in fig. 1: 26ab for MS line 28 and 26cd for FW line 30), wherein each of the isolation valves includes two actuators (“A fast-closing gate valve with a system steam-actuated piston could be used for this purpose,” col. 5, ll. 41-43; e.g., 26ab has two actuators, one for 26a and one for 26b).
Regarding claim 9, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses wherein the emergency coolant loop includes an isolation condenser outside the containment structure (“isolation condensers will remove the long-term decay heat,” col. 2, ll. 56-57; the lines that lead to them are in the upper portion of the containment, col. 4, ll. 56-58), and wherein the plant lacks any other emergency coolant system for the reactor (“Other emergency core cooling systems are not needed,” col. 3, ll. 1-2).
Regarding claim 10, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses wherein the containment structure lacks a pump and lacks an emergency reservoir of coolant flowing into the reactor (“Other emergency core cooling systems are not needed,” col. 3, ll. 1-2).
Regarding claim 12, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses wherein the reactor is sized to generate Megawatts of thermal energy through nuclear fission (boiling water reactor,” see title), the plant further comprising: a plurality of isolation valves (26) at each connection of the reactor and the primary and emergency coolant loops (col. 2, ll. 28-31; e.g., in fig. 1: 26ab for MS line 28 and 26cd for FW line 30), wherein each of the isolation valves includes two actuators (“A fast-closing gate valve with a system steam-actuated piston could be used for this purpose,” col. 5, ll. 41-43; e.g., 26ab has two actuators, one for 26a and one for 26b).
Gou does not explicitly disclose the amount of thermal energy generated. Isberg does. Isberg teaches that the reactor is sized to generate approximately 900 Megawatts of thermal energy through nuclear fission (1246 MW, table 1). The skilled artisan would have been motivated, prior to the effective filing date of the invention, to have utilized Isberg’s thermal energy for “a turbine plant 24 to generate electric current,” col. 8, ll. 47-50. The skilled artisan is aware that a plant that can produce 1246 MWt can also produce 900 MWt based on demand.
Regarding claim 13, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses wherein the vessel has a multi-meter diameter and height (boiling water reactor,” see title), and Isberg teaches the vessel is over 3 meters in diameter (5 meters, table 1) and up to 28 meters in height (17 meters, table 1). The skilled artisan would have been motivated, prior to the effective filing date of the invention, to have utilized Isberg’s elongate reactor shape for the obvious benefit of a greater surface area available for cooling by the surrounding ground. A tall, lidded coffee cup loses heat quicker than a short one. Examiner notes that, similar to the underground benefit, a more elongated vessel will offer greater protection against leakage and missile strikes because the most radioactive portion—the core—is near the bottom of the reactor and would be farther from the ground surface.
Moreover, it would have been an obvious matter of design choice to have a long cylindrical shape, since such a modification would have involved a mere increase in elongation of an already elongated component. A change in size or shape is generally recognized as being within the level of ordinary skill in the art.
Claims 5 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Gou (US 5,577,085) and Isberg (US 3,712,851), as combined above, further in view of Schabert (US 4,057,077).
Regarding claims 5 and 11, the above-described modification of Gou with Isberg teaches all the elements of the parent claim. Additionally, Gou discloses that the containment structure comprises steel (“steel liner 4,” col. 3, l. 60).
This combination does not explicitly suggest using only steel for the containment vessel. Schabert does. Schabert is also in the art area of nuclear reactors and teaches (fig. 2) reactor shielding that, like Gou, uses both steel (4) and concrete (25, 35) but, unlike Gou, has them spaced apart from each other, such that the containment vessel (4) is entirely steel (“col. 3, ll. 50-51: “steel shell containment 4”). The ordinary skilled artisan would have been motivated, prior to the effective filing date of the invention, to have utilized Schabert’s all-steel containment for its efficacy for “enclos[ing] the high-pressure-carrying parts,” col. 3, ll. 51-52, but also for the apparent benefit that the wall penetrations (3 and 38 in fig. 2 of Schabert) will be much easier to access for maintenance, repairs, and insertion of any monitoring or inspection equipment when they are spaced apart from each other.
Schabert’s design still retains the benefits of the concrete 25, 35, while offering the additional benefit of ease of access. The skilled artisan is able to determine the pros and cons of having barriers flush against each other versus spaced apart and make a design choice decision based on the priorities of that particular reactor facility.
Put another way, it would have been an obvious matter of design choice to have used steel alone, concrete alone, or a steel/concrete combination, all of which are known in the art, since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. Applicant notes in ¶ 17 of the published application that steel, concrete, or steel-plus-concrete would all work.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to LILY C GARNER whose telephone number is (571)272-9587. The examiner can normally be reached 9-5 CT.
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LILY CRABTREE GARNER
Primary Examiner
Art Unit 3646
/LILY C GARNER/Primary Examiner, Art Unit 3646
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