FINAL OFFICE ACTION
This Final Office action addresses U.S. Application Serial No. 18/507,694, entitled PLANAR TRANSFORMER.
Claims 1-3 and 5-14 are pending.
Claims 1-3, 5 and 6 are rejected.
Claims 7-14 are allowed.
I. STATUS OF CLAIMS AND APPLICATION
Applicant filed an amendment on September 9, 2016 (hereinafter the “Sept 2026 Amendment”) in response to the Office action mailed June 29, 2026 (hereinafter the “2026 NF Action”). In the Sept 2026 Amendment, claims 1, 5, 7, 11, 12 and 13 were amended, claims 2, 3, 6, 8-10 and 14 were unchanged and claim 4 was cancelled. Therefore, claims 1-3 and 5-14 are pending.
In view of the substantial amendments to the claims in the Sept 2026 Amendment, all objections and rejections provided in the 2026 NF Action are withdrawn. However, such amendments necessitated the amended rejections provided in this Office action. Thus, this action is made Final.
II. PRIORITY
Examiner recognizes the Applicant’s claim of priority to U.S. Provisional Application No. 63/425,014, filed November 14, 2022.
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. 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.
IV.A. Anticipation Rejections Applying Huang
Claims 1-3 and 5 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by U.S. Patent Application Publication No. 2023/0162905 to Xiucheng Huang et al., published on May 25, 2023 and having a filing date of at least February 7, 2022 (hereinafter “Huang”).
Regarding claim 1, Huang discloses:
1. A planar transformer applied to an isolated converter, the isolated converter comprising a primary-side circuit and a secondary-side circuit, the planar transformer comprising:
See Huang Title “PLANAR TRANSFORMER” and FIG. 14, reprinted below, for general circuit configuration and FIG. 12, reprinted below for transformer structure relevant to this rejection.
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a circuit board arranged in the isolated converter, the circuit board comprising:
See Huang ¶0023 wherein which states “FIG. 12 illustrates a simplified partial cross-sectional view through a region of a PCB-based transformer, according to embodiments of the disclosure.” Further see Huang ¶0028 which states “in some embodiments a transformer is formed from a multilayer PCB that includes windings formed around a magnetic core.”
a primary-side trace formed on a primary-side layer of the circuit board, and the primary-side trace configured to serve as a primary-side coil coupled to the primary-side circuit; and
See Huang FIG. 12 above, note primary side trace P2 on a primary-side layer circuit board, which serves as part the primary side circuit part.
a secondary-side trace formed on a secondary-side layer of the circuit board, and the secondary-side trace configured to serve as a secondary-side coil coupled to the secondary-side circuit; and
See Huang FIG. 12 above, note secondary side trace S2 on a secondary-side layer circuit board, which serves as part the secondary side circuit.
an iron core comprising a core pillar, the core pillar penetrating a through hole of the circuit board, and the primary-side trace and the secondary-side trace surrounding the through hole;
See Huang FIG. 12 above, note E-I core 1225 shown.
at least one auxiliary trace configured to serve as at least one auxiliary coil,
See Huang FIG. 12 above, auxiliary trace AP-1.
wherein the secondary-side layer and the primary-side layer respectively comprise a secondary-side adjacent layer and a primary-side adjacent layer adjacent to each other;
See Huang FIG. 12 above, first Examiner finds that each trace layer is provided on a respective layer as shown and discussed throughout Huang. Further note secondary-side adjacent layer including secondary side trace S2 is provided on a layer that is adjacent (or near) primary side adjacent layer including primary trace P2.
a first width is formed by the secondary-side trace of the secondary-side adjacent layer, and a second width is formed by the at least one auxiliary trace and the primary-side trace of the primary-side adjacent layer and the first width is greater than or equal to the second width.
See Huang FIG. 12 above, note secondary side trace S2 on secondary-side adjacent layer has a width (in the radial direction around the central core post) that is greater than the width of combination of the primary side trace P2 and auxiliary trace AP-1 on the primary side adjacent layer.
Regarding claim 2, Huang discloses the transformer of claim 1 as evidenced above and further:
2. The planar transformer as claimed in claim 1, wherein the number of the primary-side layers is plural and the number of the secondary-side layers is plural; each primary-side layer comprises the primary-side trace, and each secondary-side layer comprises the secondary-side trace; the primary-side traces are close to a center of the circuit board and the secondary-side traces are away from the center to form a sandwich trace.
See Huang FIG. 12 above, note primary side layers having traces P1 and P2 which are closer to the center of the PCB board array than secondary side layers having traces S1 and S2.
Regarding claim 3, Huang discloses the transformer of claim 1 as evidenced above and further:
3. The planar transformer as claimed in claim 1, wherein the circuit board further comprises: at least one auxiliary trace formed on the primary-side layer to serve as at least one auxiliary coil, wherein the at least one auxiliary trace surrounds the through hole to form a concentric structure with the primary-side trace.
See Huang FIG. 12 above, note auxiliary trace Ap1 on the layer of the primary side trace P2 layer and surrounds the hole for the core and are concentric with the primary side trace P2.
Regarding claim 5, Huang discloses the transformer of claim 3 as evidenced above and further:
5. The planar transformer as claimed in claim 3, wherein the number of turns surrounding the through hole of at least one of the primary-side trace, the secondary-side trace, and the at least one auxiliary trace is not an integer.
See Huang FIG. 8 which illustrates a secondary side trace S2/110 which illustrates the traces has greater than one turn of winding, not any integer.
V. 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.
V.A. Obviousness Rejection Applying Huang and Rowley
Claim 6 is rejected under 35 U.S.C. §103 as being unpatentable over Huang in view of U.S. Patent No. 6,124,778 to Anna Rowley et al. (hereinafter “Rowley”). Regarding this claims, Huang teaches the features of the transformers of claim as provided above, but not any mounting of the transformer. Nevertheless, Rowley teaches a planar transformer assembly wherein primary and secondary circuits are mounted onto a circuit board (See Rowley FIG. 1) and further teaches its transformer board “vertical mounted on the PCB into a power supply motherboard” (See Rowley col. 8, lines 62-64) via plug connects (See Rowley FIG. 1, connectors 26). It would have been obvious at the time the invention was filed to plug the planar transformer of Huang into a motherboard as taught by Rowley. One having ordinary skill in the art would do so first because the planar transformer of Huang is a circuit component which would in ordinary use be mounted onto a larger main circuit board. Furthermore, such a mounted as suggested in Rowley would be vertically into a motherboard to save space on the main/motherboard while maintaining a “very low profile.” See Rowley col. 8, line 64 to col. 9, line 1.
VI. ALLOWABLE SUBJECT MATTER
Claims 7-14 are allowed. Regarding these claims, the prior art of record in this application does not show or teach “wherein the iron core comprises an air gap having a first distance; the primary side trace, primary-side second distance is defined between the primary-side trace and the through hole, a secondary-side second distance is defined between the secondary-side trace and the through hole, and each of the primary-side second distance and the secondary-side second distance is greater than or equal to three times of the first distance” in the manner as recited in these claims and in combination with the other features of the claims.
VII. EXAMINER’S RESPOSNE TO APPLICANT’S ARGUMENTS
Examiners acknowledge the Applicant’s arguments provided in the Sept 2026 Amendment. However, the arguments regarding the objections and the rejections under 35 U.S.C. §112 are moot in view of the amendments made to the claims.
On pages 8-11 of the Sept 2026 Amendment, Applicant argues that Huang does not disclose the features of claim 1 and 7 as amended in the Sept 2026 Amendment. Examiner disagrees in part as provided in this Office action. Specifically, Examiner does not agree that the amendments to claim 1 overcome the disclosure of Huang and thus new/amended rejections applying Huang and Huang in view of Rowley are provided in this Office action. Nevertheless, Examiner does agree that the amendments to claim 7 are sufficient to overcome the prior art cited in this action and thus claims 7-14 are indicated as having allowable subject matter.
INFORMATION MATERIAL TO PATENTABILITY
Applicant is further reminded of the continuing obligation under 37 C.F.R. §1.56 to timely apprise the Office of any information which is material to patentability of the claims under consideration in this reissue application.
X. CONCLUSION
Claims 1-3 and 5-14 are pending.
Claims 1-3, 5 and 6 are rejected.
Claims 7-14 are allowed.
Applicant's substantial amendments provided in the Sept 2026 Amendment necessitated the new/amended grounds of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP §706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 C.F.R. §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 C.F.R. §1.17(a)) pursuant to 37 C.F.R. §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.
The prior art made of record which is considered pertinent to Applicant’s disclosure is listed on the document titled ‘Notice of Reference Cited’ (“PTO-892”). Unless expressly noted otherwise by the Examiners, all documents listed on the PTO-892 are cited in their entirety.
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 on 8:30am - 5:00pm, Monday - Friday.
If attempts to reach the Examiner by telephone are unsuccessful, the Examiner’s supervisor, Andrew J. Fischer, SPE Art Unit 3992, can be reached at (571) 272-6779. The fax phone number for the organization where this application or proceeding is assigned is 571-273-9900.
/KENNETH WHITTINGTON/Primary Examiner, Art Unit 3992
