Prosecution Insights
Last updated: April 19, 2026
Application No. 18/296,639

WIRE-WOUND INDUCTOR USING MAGNETIC CORES WITH THREE AIR GAPS

Non-Final OA §102§103§112
Filed
Apr 06, 2023
Examiner
WHITTINGTON, KENNETH
Art Unit
3992
Tech Center
3900
Assignee
Acme Electronics Corporation
OA Round
1 (Non-Final)
71%
Grant Probability
Favorable
1-2
OA Rounds
2y 10m
To Grant
54%
With Interview

Examiner Intelligence

Grants 71% — above average
71%
Career Allow Rate
298 granted / 420 resolved
+11.0% vs TC avg
Minimal -17% lift
Without
With
+-16.8%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
33 currently pending
Career history
453
Total Applications
across all art units

Statute-Specific Performance

§101
1.4%
-38.6% vs TC avg
§103
31.5%
-8.5% vs TC avg
§102
27.6%
-12.4% vs TC avg
§112
17.7%
-22.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 420 resolved cases

Office Action

§102 §103 §112
NON-FINAL OFFICE ACTION This non-final Office action addresses U.S. Application Serial No. 18/296,639, entitled WIRE-WOUND INDUCTOR USING MAGNETIC CORES WITH THREE AIR GAPS. Claims 1-10 are pending. Claims 1-10 are rejected. I. PRIORITY Examiner recognizes the Applicant’s claim of foreign priority to Taiwan Patent Application No. TW112102622, filed January 19, 2023. II. CLAIM REJECTIONS – 35 U.S.C. §112 The following is a quotation of 35 U.S.C. §112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. Claims 8-10 are rejected under 35 U.S.C. §112(b) as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, regards as the invention. Examiner first finds that claims 8-10 are apparatus claims directed to the structures of an inductor as explicitly recited in each of the claims. Apparatus claims cover what a device is, not the manner to which it is made. “Even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself.” See MPEP §2113. Second, Examiner finds each of claims 8-10 contain method requirements directed to the manner which the inductor is made. For example, claim 8 recites “adjusting a distance defining the first air gap, the second air gap and the third air gap.” Claim 9 recites the insulating members are “sized according to material of the magnetic housing and of the magnetic posts of the wire-wound inductor.” Finally, claim 10 recites the air gaps are “defined by shorter distances when the magnetic posts are made of a magnetic alloy than when the magnetic posts are made of a ferrite.” Based on these findings, Examiner finds claims 8-10 are hybrid claims, reciting both apparatus structures and method limitations related to how the structures are adjusted, sized and/or defined. However, Examiner is unable to determine what are the parameters of these method steps. Specifically, how are the gaps “adjusted” to achieve the specific tolerance? How are the insulating members “sized” according to the other components. Finally, how the gaps “defined” when a magnetic alloy is used compared to only ferrite? Examiners thus find the claims provide little or no guidance on the manner to which these method steps are carried out and thus are unable to determine what structures are implied by such method steps. Accordingly, Examiner finds one having ordinary skill would not be able to discern the scope of the structures of the gaps/insulating members implied by these undefined methods of making and thus Examiner concludes the claims are indefinite. III. CLAIM INTERPRETATION After careful review of the original specification, the prosecution history, and unless expressly noted otherwise by the Examiner, the Examiner is unable to locate any lexicographic definitions (either express or implied) with the required clarity, deliberateness, and precision with regard to pending and examined claims. Because the Examiner is unable to locate any lexicographic definitions with the required clarity, deliberateness, and precision, the Examiner concludes that Applicant is not his own lexicographer for the pending and examined claims. See MPEP §2111.01(IV). The Examiner further finds that because the pending and examined claims herein recite neither “step for” nor “means for” nor any substitute therefore, the examined claims fail Prong (A) as set forth in MPEP §2181(I). Because all examined claims fail Prong (A) as set forth in MPEP §2181(I), the Examiner concludes that all examined claims do not invoke 35 U.S.C. §112(f). See also Ex parte Miyazaki, 89 USPQ2d 1207, 1215-16 (B.P.A.I. 2008)(precedential)(where the Board did not invoke 35 U.S.C. § 112(f) because “means for” was not recited and because applicant still possessed an opportunity to amend the claims). Because of the Examiner’s findings above that Applicant is not his own lexicographer and the pending and examined claims do not invoke 35 U.S.C. §112(f) the pending and examined claims will be given the broadest reasonable interpretation consistent with the specification since patentee has an opportunity to amend claims. See MPEP §2111, MPEP §2111.01 and In re Yamamoto et al., 222 USPQ 934 (Fed. Cir. 1984). Under a broadest reasonable interpretation, words of the claim must be given their plain meaning, unless such meaning is inconsistent with the specification. See MPEP §2111.01(I). It is further noted it is improper to import claim limitations from the specification, i.e., a particular embodiment appearing in the written description may not be read into a claim when the claim language is broader than the embodiment. See MPEP §2111.01(II). IV. COMPACT PROSECUTION The Examiner finds that because claims 8-10 are indefinite under 35 U.S.C. §112(B) as outlined above, it is impossible to properly construe claim scope at this time. See Honeywell International Inc. v. ITC, 68 USPQ2d 1023, 1030 (Fed. Cir. 2003) (“Because the claims are indefinite, the claims, by definition, cannot be construed.”). However, in accordance with MPEP §2173.06 and the USPTO’s policy of trying to advance prosecution by providing art rejections even though these claims are indefinite, the claims are construed and the art is applied as much as practically possible in the following art rejections. As best understood in view of the indefiniteness, Examiner further finds that claims 8-10 are generally product-by-process type claims, i.e., a product defined by how the structures are made/arranged. As provided in MPEP 2113(I), the patentability of product-by-process claims are defined by the products itself. Thus, Examiners will interpret claims 8-10 based on the positively recited structures of the inductor in these claims, regardless of the manner to which the inductor is made, adjusted, sized, defined or arranged. Examiners finally note the art-based rejections of claims 8-10 are merely being provided to put Applicant on notice how the art would be applied if the indefiniteness rejection were overcome. V. CLAIM REJECTIONS – 35 U.S.C. §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)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. (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. V.A. Anticipation Rejections Applying Yamaguchi Claims 1-3, 5 and 7-10 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by U.S. Patent Application Publication No. 2018/0233281 to Takayuki Yamaguchi et al. (hereinafter “Yamaguchi”). Regarding claim 1, Yamaguchi discloses: 1. A wire-wound inductor using magnetic cores with three air gaps, comprising: See Yamaguchi FIGS. 3A, 3B and 4, reprinted below: PNG media_image1.png 652 376 media_image1.png Greyscale PNG media_image2.png 566 444 media_image2.png Greyscale Yamaguchi FIG. 3A/3B Yamaguchi FIG. 4 a magnetic housing, two magnetic posts provided at central portions of two opposing inner sides of the magnetic housing respectively, See Yamaguchi FIGS. 3A, 3B and 4 above, magnetic housing comprising core portions 15A-15D. an isolation unit provided in the magnetic housing and enclosing the magnetic posts, and See FIGS. 3A, 3B and 4 above, isolation unit 40A. a coil provided on the isolation unit, See FIGS. 3A, 3B and 4 above, coil 20. wherein a non-magnetic insulating member is provided between one of the two opposing inner sides of the magnetic housing and a corresponding said magnetic post to form a first air gap, another non-magnetic insulating member is provided between the other of the two opposing inner sides of the magnetic housing and a corresponding said magnetic post to form a second air gap, and a third air gap is formed between the two magnetic posts. See FIGS. 3A, 3B and 4 above, insulating members 16A-16C provided between magnetic housing and posts 15A-15D forming three air gaps. Regarding claim 2, Yamaguchi discloses the inductor of claim 1 and further wherein: 2. The wire-wound inductor of claim 1, wherein the two opposing inner sides of the magnetic housing are flat surfaces. See FIGS. 3A, 3B and 4 above, note inner surfaces of the magnetic housing surfaces 15A and 15D have flat surfaces where they abut the insulating members 16A and 16C. Regarding claim 3, Yamaguchi discloses the inductor of claim 1 and further wherein: 3. The wire-wound inductor of claim 1, wherein the magnetic housing and the magnetic posts form an assembly of a PM configuration, a PQ configuration, or an RM configuration. See FIGS. 3A, 3B and 4 above, and FIG. 2, reprinted below, note streamline pot-core shape. PNG media_image3.png 336 570 media_image3.png Greyscale Yamaguchi FIG. 2 Regarding claim 5, Yamaguchi discloses the inductor of claim 1 and further wherein: 5. The wire-wound inductor of claim 1, wherein magnetic posts are made of a manganese-zinc ferrite, a nickel-zinc ferrite, a magnesium-zinc ferrite, an iron-silicon alloy, an iron-nickel alloy, an iron-silicon-aluminum alloy, a nickel-iron-molybdenum alloy, an amorphous alloy, or a nanocrystalline alloy. See Yamaguchi ¶0071 wherein the material for the core 15A-15D are made from “pure iron or an iron alloy containing at least one kind of additive element selected from elements of Ni, Cu, Cr, Mo, Mn, C, Si, Al, P, B, N and Co.” Regarding claim 7, Yamaguchi discloses the inductor of claim 1 and further wherein: 7. The wire-wound inductor of claim 1, wherein the first air gap and the second air gap are defined by a same distance. See FIGS. 3A, 3B and 4 above, note spacings for the gaps at non-magnetic layers 16A-16C. Regarding claim 8, as best understood in view of the indefiniteness and claim interpretation above, Yamaguchi discloses the inductor of claim 1 and further wherein: 8. The wire-wound inductor of claim 1, wherein the wire-wound inductor has an inductance tolerance controllable within ±5% by adjusting a distance defining the first air gap, the second air gap, or the third air gap. See FIGS. 3A, 3B and 4 above, note Yamaguchi discloses air gaps which are defined during manufacturing to arrive at the inductor shown. Since the inductor Yamaguchi contains all the positively recited structures required in claim 8, the inductor would have the same properties and further reads on the product-by-process making thereof. Regarding claim 9, as best understood in view of the indefiniteness and claim interpretation above, Yamaguchi discloses the inductor of claim 1 and further wherein: 9. The wire-wound inductor of claim 1, wherein the non-magnetic insulating members are sized according to materials of the magnetic housing and of the magnetic posts of the wire-wound inductor. See FIGS. 3A, 3B and 4 above, note Yamaguchi discloses insulating members in the air gaps which are sized during manufacturing to arrive at the inductor shown. Since the inductor Yamaguchi contains all the positively recited structures required in claim 8, the inductor would have the same properties and further reads on the product-by-process making thereof. Regarding claim 10, as best understood in view of the indefiniteness and claim interpretation above, Yamaguchi discloses the inductor of claim 1 and further wherein: 10. The wire-wound inductor of claim 1, wherein the first air gap, the second air gap, and the third air gap are respectively defined by shorter distances when the magnetic posts are made of a magnetic alloy than when the magnetic posts are made of a ferrite. See FIGS. 3A, 3B and 4 above and Yamaguchi ¶0071 wherein the material for the core 15A-15D are made from “pure iron or an iron alloy containing at least one kind of additive element selected from elements of Ni, Cu, Cr, Mo, Mn, C, Si, Al, P, B, N and Co.” Thus, the magnetic posts are made from the same material as contemplated by Applicant and thus would have the same properties over a simple ferrite post. V.B. Anticipation Rejections Applying Huang Claims 1-3 and 7-9 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Taiwan Patent Publication No. TWM494994 to Jia-Ping Huang et al. (hereinafter “Huang”). Regarding claim 1, Huang discloses: 1. A wire-wound inductor using magnetic cores with three air gaps, comprising: See Huang FIGS. 2 and 4, reprinted below: PNG media_image4.png 504 678 media_image4.png Greyscale PNG media_image5.png 370 278 media_image5.png Greyscale Huang FIG. 2 Huang FIG. 4 a magnetic housing, two magnetic posts provided at central portions of two opposing inner sides of the magnetic housing respectively, See Huang FIGS. 2 and 4 above, magnetic housing comprising core portions 2 and 3. an isolation unit provided in the magnetic housing and enclosing the magnetic posts, and See FIGS. 2 and 4 above, isolation unit 11. a coil provided on the isolation unit, See FIGS. 2 and 4 above, coil 12. wherein a non-magnetic insulating member is provided between one of the two opposing inner sides of the magnetic housing and a corresponding said magnetic post to form a first air gap, another non-magnetic insulating member is provided between the other of the two opposing inner sides of the magnetic housing and a corresponding said magnetic post to form a second air gap, and a third air gap is formed between the two magnetic posts. See FIGS. 2 and 4 above, insulating members 4 provided between magnetic housing and posts 2 and 3 forming three air gaps. Regarding claim 2, Huang discloses the inductor of claim 1 and further wherein: 2. The wire-wound inductor of claim 1, wherein the two opposing inner sides of the magnetic housing are flat surfaces. See FIGS. 2 and 4 above, note inner surfaces of the magnetic housing surfaces 2 have flat surfaces where they abut the insulating members 4. Regarding claim 3, Huang discloses the inductor of claim 1 and further wherein: 3. The wire-wound inductor of claim 1, wherein the magnetic housing and the magnetic posts form an assembly of a PM configuration, a PQ configuration, or an RM configuration. See FIGS. 2 and 4 above, note core shape. Regarding claim 7, Huang discloses the inductor of claim 1 and further wherein: 7. The wire-wound inductor of claim 1, wherein the first air gap and the second air gap are defined by a same distance. See FIGS. 2 and 4 above, note spacings for the gaps at non-magnetic layers 4. Regarding claim 8, as best understood in view of the indefiniteness and claim interpretation above, Huang discloses the inductor of claim 1 and further wherein: 8. The wire-wound inductor of claim 1, wherein the wire-wound inductor has an inductance tolerance controllable within ±5% by adjusting a distance defining the first air gap, the second air gap, or the third air gap. See FIGS. 2 and 4 above, note Huang discloses air gaps which are defined during manufacturing to arrive at the inductor shown. Since the inductor Huang contains all the positively recited structures required in claim 8, the inductor would have the same properties and further reads on the product-by-process making thereof. Regarding claim 9, as best understood in view of the indefiniteness and claim interpretation above, Huang discloses the inductor of claim 1 and further wherein: 9. The wire-wound inductor of claim 1, wherein the non-magnetic insulating members are sized according to materials of the magnetic housing and of the magnetic posts of the wire-wound inductor. See FIGS. 2 and 4 above, note Huang discloses insulating members in the air gaps which are sized during manufacturing to arrive at the inductor shown. Since the inductor of Huang contains all the positively recited structures required in claim 8, the inductor would have the same properties and further reads on the product-by-process making thereof. VI. CLAIM REJECTIONS – 35 U.S.C. §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. VI.A. Obviousness Rejection Applying Yamaguchi and Liang Claim 4 is rejected under 35 U.S.C. §103 as being unpatentable over Yamaguchi in view of U.S. Patent Application Publication No. 2022/0208429 to Charles Sullivan et al. (hereinafter “Sullivan”). Regarding this claim, Yamaguchi teaches the features of claim 1 as evidenced above and fYamaguchi at ¶0071 wherein the material for the core members 15A-15D is made from “pure iron or an iron alloy...” However, Yamaguchi does not explicitly disclose the ferrite alloys required in claim 4. Nevertheless, Sullivan teaches magnetic core structures for inductors wherein “[t]he magnetic core materials may include, but are not limited to, one or more of iron, various steel alloys, cobalt, ferrites including manganese-zinc (MnZn) and/or nickel-zinc (NiZn) ferrites, nano-granular materials such as Co—Zr—O, and powdered core materials made of powders of ferromagnetic materials mixed with organic or inorganic binders.” See Sullivan ¶0063. It would have been obvious at the time the invention was filed to using the zinc alloys for the core members 15A-15D of Yamaguchi as taught by Sullivan. One having ordinary skill in the art would do so because as such materials, including ferrites including manganese-zinc (MnZn) and/or nickel-zinc (NiZn) ferrites are well known for use in magnetic pot type core structures as taught by Sullivan. Thus, this combination teaches the magnetic housing is made of a ferrite selected from the group consisting of a manganese-zinc ferrite, a nickel-zinc ferrite, and a magnesium-zinc ferrite, and the magnetic posts are made of a ferrite or a magnetic alloy (which would include those listed). VI.B. Obviousness Rejection Applying Yamaguchi and Liang Claim 6 is rejected under 35 U.S.C. §103 as being unpatentable over Yamaguchi in view of Japanese Publication No. JP2018074146 to Liang Zhiyong et al. (hereinafter “Liang”). Regarding claim 6, Yamaguchi discloses the non-magnetic insulating members to form the air gaps, but not the material therefore. Nevertheless, Liang in FIG. 6, reprinted below, teaches a gapped core 40A having three air gaps with insulating members 44a-44c in the air gaps. Furthermore, Liang teaches the insulating PNG media_image6.png 210 220 media_image6.png Greyscale Liang FIG. 6 members are made from synthetic resins, i.e., polyester. It would have been obvious at the time the invention was made to make the insulating members of Yamaguchi out of polyester as taught by Liang. One having ordinary skill in the art would do so because making such insulating member out of polyester is well known in the art as explicitly taught by Liang as provided above. VII. CONCLUSION Claims 1-10 are pending. Claims 1-10 are rejected. Any inquiry concerning this communication or earlier communications from the examiner should be directed to KENNETH WHITTINGTON whose telephone number is (571) 272-2264. The examiner can normally be reached 8:30am - 5:00pm, Monday - Friday. 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, Andrew Fischer can be reached at (571) 272-6779. 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. /KENNETH WHITTINGTON/Primary Examiner, Art Unit 3992
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Prosecution Timeline

Apr 06, 2023
Application Filed
Jan 26, 2026
Non-Final Rejection — §102, §103, §112 (current)

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Prosecution Projections

1-2
Expected OA Rounds
71%
Grant Probability
54%
With Interview (-16.8%)
2y 10m
Median Time to Grant
Low
PTA Risk
Based on 420 resolved cases by this examiner. Grant probability derived from career allow rate.

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