Prosecution Insights
Last updated: April 19, 2026
Application No. 17/708,154

IRON CORE STRUCTURE IN TRANSFORMER AND VOLTAGE CONVERTER

Non-Final OA §102§103
Filed
Mar 30, 2022
Examiner
NGUYEN, TUYEN T
Art Unit
2837
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Fulian Precision Electronics (Tianjin) Co., Ltd.
OA Round
1 (Non-Final)
82%
Grant Probability
Favorable
1-2
OA Rounds
2y 9m
To Grant
82%
With Interview

Examiner Intelligence

Grants 82% — above average
82%
Career Allow Rate
1001 granted / 1226 resolved
+13.6% vs TC avg
Minimal +1% lift
Without
With
+0.8%
Interview Lift
resolved cases with interview
Typical timeline
2y 9m
Avg Prosecution
50 currently pending
Career history
1276
Total Applications
across all art units

Statute-Specific Performance

§101
0.1%
-39.9% vs TC avg
§103
54.5%
+14.5% vs TC avg
§102
22.9%
-17.1% vs TC avg
§112
17.7%
-22.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1226 resolved cases

Office Action

§102 §103
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 without traverse of Group I, Specie I, Figure 1 and claims 1-10 in the reply filed on 9/23/2025 is acknowledged. Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Claim(s) 1-3, 5, 7 and 9-10 is/are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Morris [US 5,555,494]. Regarding claims 1-2, 5 and 7, Morris discloses an iron core structure [figure 9] comprising: a primary winding [P]; a secondary winding [S1, S2]; and an iron core, wherein the primary winding and the secondary winding are twisted around the iron core; wherein the iron core comprises a first core member and a second core member, the first core member comprises a first side leg [71], a second side leg [72], and a first center leg spaced apart from the first and the second side legs; the second core member comprises a third side leg [71], a fourth side leg [72], and a second center leg spaced apart from the third and the forth side legs; the first center leg is connected to the second center leg, wherein the first side leg and the second first leg are symmetrically positioned at two opposite sides of the first center leg and wherein the first center leg and the second center leg are connected in one piece [figure 9] a first gap [81] is defined between the first side leg and the third side leg; a second gap [82] is defined between the second side leg and the fourth side leg, wherein a size of the first gap is equal to a size of the second gap [figure 9]; the primary winding [P] is positioned on the first center leg and the second center leg [figure 9]; the secondary winding comprises a first secondary winding [S1] and a second secondary winding [S2], the first secondary winding is arranged around the first gap, the second secondary winding is arranged around the second gap. Regarding claim 3, Morris discloses the first side leg is coaxially positioned with the third side leg, the second side leg is coaxially positioned with the fourth side leg [figure 9]. Regarding claim 9, Morris discloses material of the iron core comprises silicon steel sheet or ferrite [column 20, line 67]. Regarding claim 10, Morris further disclose the first core member further comprises a first connecting portion, the first side leg, the first center leg, and the second side leg are connected to the first connecting portion in one piece; the second core member further comprises a second connecting portion, the third side leg, the second center leg, and the fourth side leg are connected to the second connecting portion in one piece [figure 9]. 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. Claim(s) 1-10 are is/are rejected under 35 U.S.C. 103 as being unpatentable over Njiende et al. [US 10,389,258 B2] in view of Morris [US 5,555,494]. Regarding claims 1-2 and 5, Njiende et al. discloses an iron core structure [figure 11a] comprising: a primary winding [720]; a secondary winding [721]; and an iron core, wherein the primary winding and the secondary winding are twisted around the iron core; wherein the iron core comprises a first core member [731] and a second core member [732], the first core member comprises a first side leg [731.2], a second side leg [731.4], and a first center leg [731.3] spaced apart from the first and the second side legs; the second core member comprises a third side leg [732.2], a fourth side leg [732.4], and a second center leg [732.3] spaced apart from the third and the forth side legs; wherein the first side leg and the second first leg are symmetrically positioned at two opposite sides of the first center leg and wherein the first center leg and the second center leg are connected in one piece [figure 11a] a first gap [719a] is defined between the first side leg and the third side leg; a second gap [719b] is defined between the second side leg and the fourth side leg, wherein a size of the first gap is equal to a size of the second gap [figure 11a]; the secondary winding comprises a first secondary winding [721a] and a second secondary winding [721b], the first secondary winding is arranged around the first gap, the second secondary winding is arranged around the second gap. Njiende et al. disclose the instant claimed invention except for the primary winding is positioned on the first center leg and the second center leg. Morris discloses the primary winding [P] positioned on the center leg of the core structure [figure 9, see above]. It would have been an obvious to one having ordinary skill in the art, before the effective filing date of the claimed invention, to arrange the primary winding on the center legs of Njiende et al., as suggested by Morris, for the purpose of facilitating different magnetic flux/field. Regarding claims 3-4, Njiende et al. further discloses the first side leg is coaxially positioned with the third side leg, the second side leg is coaxially positioned with the fourth side leg [figure 11a], wherein a length of the first center leg is greater than a length of the first side leg; a length of the second center leg is greater than a length of the third side leg and wherein a size of the first gap is equal to a size of the second gap [figure 11a]. Regarding claim 6, Njiende et al. discloses a cross area of the first center leg is greater than a cross area of the first center leg [figure 11a]. Regarding claim 7, Morris discloses the center legs connected [figure 9]. Regarding claim 9, Morris discloses the use of ferrite for the magnetic core structure [column 20, line 67]. Regarding claim 10, Njiende et al. discloses the first core member further comprises a first connecting portion [731.1], the first side leg, the first center leg, and the second side leg are connected to the first connecting portion in one piece; the second core member further comprises a second connecting portion [732.1], the third side leg, the second center leg, and the fourth side leg are connected to the second connecting portion in one piece [figure 11]. Regarding claim 8, the specific gap size would have been an obvious design consideration for the purpose of controlling the magnetic leakage/inductance and/or flux/field. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to TUYEN T NGUYEN whose telephone number is (571)272-1996. The examiner can normally be reached Mon - Fri 8:30-5:30. 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, Shawki Ismail can be reached at 571-272-3985. 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. /TUYEN T NGUYEN/ Primary Examiner, Art Unit 2837
Read full office action

Prosecution Timeline

Mar 30, 2022
Application Filed
Aug 18, 2025
Response after Non-Final Action
Nov 29, 2025
Non-Final Rejection — §102, §103
Apr 07, 2026
Response Filed

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

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Prosecution Projections

1-2
Expected OA Rounds
82%
Grant Probability
82%
With Interview (+0.8%)
2y 9m
Median Time to Grant
Low
PTA Risk
Based on 1226 resolved cases by this examiner. Grant probability derived from career allow rate.

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