Prosecution Insights
Last updated: April 19, 2026
Application No. 18/281,727

ARC EXTINGUISHING UNIT AND AIR CIRCUIT BREAKER COMPRISING SAME

Non-Final OA §103§DP
Filed
Sep 12, 2023
Examiner
BOLTON, WILLIAM A
Art Unit
2831
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Ls Electric Co. Ltd.
OA Round
3 (Non-Final)
89%
Grant Probability
Favorable
3-4
OA Rounds
2y 0m
To Grant
95%
With Interview

Examiner Intelligence

Grants 89% — above average
89%
Career Allow Rate
657 granted / 738 resolved
+21.0% vs TC avg
Moderate +6% lift
Without
With
+5.6%
Interview Lift
resolved cases with interview
Fast prosecutor
2y 0m
Avg Prosecution
30 currently pending
Career history
768
Total Applications
across all art units

Statute-Specific Performance

§101
0.1%
-39.9% vs TC avg
§103
51.7%
+11.7% vs TC avg
§102
32.0%
-8.0% vs TC avg
§112
11.1%
-28.9% vs TC avg
Black line = Tech Center average estimate • Based on career data from 738 resolved cases

Office Action

§103 §DP
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. The Amendment filed February 19th, 2026 has been entered. Claims 1-2, 4-5 and 8-13 are pending. Claims 1 and 10-11 have been amended and claims 3 and 6-7 have been canceled by the Applicant. Drawings The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the “plurality of fixed contacts” of claims 1 and 10, must be shown or the feature(s) canceled from the claim(s). No new matter should be entered. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance. Claim Objections Claims 1 and 10 are objected to because: Claim 1, line 15, “a” before at least one of the plurality of movable contacts should be deleted. Claims 10-11, phrase, “low runner” is a relative and depends on the circuit breaker’s orientation and the observer’s perspective. Claim 10, line 20, word, “downward” is relative and therefore renders scope of claim unclear and will depends on orientation and the observer’s perspective. Appropriate correction is required. Double Patenting 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). 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 § 2146 et seq. 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). The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13. The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual 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/apply/applying-online/eterminal-disclaimer. Claims 1 and 10-13 provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 3-7 and 13-14 of copending Application No. 18286308 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because both sets of claims are directed to a circuit breaker comprising arc extinguishing devices, with differences between the two sets of claims being only minor variations in recited scope that are not seen to involve an inventive step when the abilities of persons of ordinary skill are taken into full consideration. This is a provisional non-statutory double patenting rejection because the patentably indistinct claims have not in fact been patented. 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. Claims 1-2 and 4-5 are rejected under 35 U.S.C. 103 as being unpatentable over Liu et al, CN 112017881 [Liu] in view of Hamada et al, US 20130284702 [Hamada] and further in view of Park, KR 19980054537. Regarding claim 1, Hamada discloses (figs.1-9) an arc extinguishing unit (11), comprising: side plates (12a, 12b) spaced apart from each other and disposed to face each other; a plurality of grids (13) disposed between the side plates (12a, 12b), spaced apart from each other, and coupled to the side plates (12a, 12b), respectively; and a grid cover (12c) disposed on the plurality of grids (13) to cover the plurality of grids (13), where each grid (13) of the plurality of grids (13) comprises a grid leg (13b) extending from both ends in a width direction towards a region where an arc is generated so that an induced magnetic field (17a) can be formed by the arc (16a), and where the grid leg (13b) comprises: a first grid leg (13b) extending from a first end of a respective grid (13) of the plurality of grids (13) in the width direction; and a second grid leg (13b) from a second end of the respective grid (13), opposite the first end, where the first grid leg (13b) and the second grid leg (13b) are equal in width. Hamada fails to explicitly disclose a plurality of fixed contacts and a plurality of movable contacts spaced apart, and wherein the grid leg is made to surround a protruding contact extending from at least one of the plurality of movable contacts in a first direction, and wherein the first grid leg and the second grid leg each have a width greater than a length of an air gap, which is a distance between the first grid leg or the second grid leg and the protruding contact. Liu discloses (figs.2-11) a circuit breaker where a plurality of fixed contacts (24) [para.0044] and a plurality of movable contacts (43) are spaced apart, where a grid leg (of plate 51) is made to surround a protruding contact (23) extending from at least one of the plurality of movable contacts (43) in in a first direction relative. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the fixed and movable contact assemblies of Hamada with the replacement of the fixed and movable contact assemblies of Liu, thereby providing an improved circuit breaker with resiliently mounted multiply arcing contacts constructed to draw the arcs away from the main current-carrying contacts in order to protect the main current-carrying from burning during contacts separation. Liu fails to explicitly disclose wherein the first grid leg and the second grid leg each have a width greater than a length of an air gap, which is a distance between the first grid leg or the second grid leg and the protruding contact. Park shows (fig.1) an arc extinguishing chamber (1) where a first grid leg and a second grid leg have a width greater than a length of an air gap, which is a distance between the first grid leg or the second grid leg. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify the grid of Hamada with the teaching of the grid of Park, thereby providing a configuration that improves the extinguishing efficiency by inducing the division of the arc by dually separating the arc on both sides around the movable contactor. Regarding claim 2, Hamada further discloses where the grid leg (13b) extends adjacent to an end of a respective one of the side plates (12a, 12b). Regarding claim 4, Park further discloses where a sum of lengths of a first grid leg and a second grid leg in the width direction is equal to or greater than half of a width of a respective grid of the plurality of grids (2). Regarding claim 5, Hamada further discloses where the first grid leg (13b) and the second grid leg (13b) comprise a first portion adjoining a main body (13a) of the respective grid (13) and a second portion extending from the first portion, and where the first portion of the first grid leg (13b) and the first portion of the second grid leg (13b) are equal in length in the width direction to each other, and the second portion of the first grid leg (13b) and the second portion of the second grid leg (13b) are equal in length in the width direction to each other [see fig.7]. Claims 10-12 are rejected under 35 U.S.C. 103 as being unpatentable over Liu and Hamada and further in view of Park. Regarding claim 10, Liu discloses (figs.2-11) an air circuit breaker, comprising: a plurality of fixed contacts (24) [para.0040]; a plurality of movable contacts (43) moved in a direction toward or away from the plurality of fixed contacts (24); a low runner (6) disposed extending in a first direction from the plurality of fixed contacts (24), a protruding contact (42) disposed extending in a first direction from at least one of the plurality of movable contacts (43), energized when in contact with the low runner (6), and spaced apart from the low runner (6) when the plurality of movable contacts (43) is tripped; and an arc extinguishing unit (5) positioned adjacent to the plurality of fixed contacts (24) and the plurality of movable contacts (43), and configured to extinguish an arc generated when the plurality of fixed contacts (24) and the plurality of movable contacts (43) are spaced apart, where the arc extinguishing unit (5) comprises: side plates spaced apart from each other and disposed to face each other a plurality of grids (51) disposed between the side plates, spaced apart from each other, and coupled to the side plates, respectively; and a grid cover disposed on the plurality of grids (51) to cover the plurality of grids (51); and the plurality of fixed contacts (24) [para.0044] and the plurality of movable contacts (43) are spaced apart. Liu fails to explicitly disclose wherein each grid of the plurality of grids comprises a grid leg extending downward from both ends in a width direction towards a region where an arc is generated so that an induced magnetic field can be formed by the arc, and wherein the grid leg comprises: a first grid leg extending from one end of a respective grid of the plurality of grids in the width direction; and a second grid leg extending opposite the first grid leg, wherein the first grid leg and the second grid leg are equal in width. Hamada discloses (figs.1-9) an arc extinguishing unit (11), comprising: where each grid of a plurality of grids (13) comprises a grid leg (13b) extending downward from both ends in a width direction towards a region where an arc (16a) is generated so that an induced magnetic field (17a) can be formed by the arc (16a), and where the grid leg (13b) comprises: a first grid leg (13b) extending from one end of a respective grid (13) of the plurality of grids (13) in the width direction; and a second grid leg (13b) extending opposite the first grid leg (13b), where the first grid leg (13b) and the second grid leg (13b) are equal in width. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the grids of Liu with the teaching of the grids of Hamada, thereby providing magnetic flux generated between the pairs of grid leg portions configuring the arc extinguishing device in a direction perpendicular to the arc generated, during contact separation. Liu and Hamada fail to disclose wherein the first grid leg and the second grid leg have a width greater than a length of an air gap, which is a distance between the first grid leg or the second grid leg and the protruding contact. Park shows (fig.1) an arc extinguishing chamber (1) where each of a first grid leg and a second grid leg have a width greater than a length of an air gap, which is a distance between the first grid leg or the second grid leg. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify the grid of Liu, with the teaching of the grid of Park, thereby providing a configuration that improves the extinguishing efficiency by inducing the division of the arc by dually separating the arc on both sides around the movable contactor. Regarding claim 11, Liu, Hamada and Park further comprising: a fixed contact terminal (Liu, 2) having the plurality of fixed contacts (24) disposed at a lower end thereof and extending in the first direction, where a first end of the low runner (6) is coupled to the fixed contact terminal (2), and a second end of the low runner (6) is spaced apart from the fixed contact terminal (2). Regarding claim 12, Liu, Hamada and Park further disclose where the grid leg (of 51) extends to surround the protruding contact (Liu, 42) from both sides. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to WILLIAM A BOLTON whose telephone number is (571)270-5887. The examiner can normally be reached Mon-Fri: 7:30AM - 5:00PM. 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. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Renee S Luebke can be reached at (571)-272-2009. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /WILLIAM A BOLTON/Primary Examiner, Art Unit 2833
Read full office action

Prosecution Timeline

Sep 12, 2023
Application Filed
Jul 12, 2025
Non-Final Rejection — §103, §DP
Oct 16, 2025
Response Filed
Nov 26, 2025
Final Rejection — §103, §DP
Feb 19, 2026
Response after Non-Final Action
Feb 27, 2026
Request for Continued Examination
Mar 09, 2026
Response after Non-Final Action
Mar 16, 2026
Non-Final Rejection — §103, §DP (current)

Precedent Cases

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

3-4
Expected OA Rounds
89%
Grant Probability
95%
With Interview (+5.6%)
2y 0m
Median Time to Grant
High
PTA Risk
Based on 738 resolved cases by this examiner. Grant probability derived from career allow rate.

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