Prosecution Insights
Last updated: April 19, 2026
Application No. 18/437,223

PERMANENT MAGNET ROTOR AND METHOD FOR MANUFACTURING SAME

Non-Final OA §103
Filed
Feb 08, 2024
Examiner
VO, ETHAN NGUYEN
Art Unit
2834
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Mahle International GmbH
OA Round
1 (Non-Final)
69%
Grant Probability
Favorable
1-2
OA Rounds
2y 6m
To Grant
93%
With Interview

Examiner Intelligence

Grants 69% — above average
69%
Career Allow Rate
25 granted / 36 resolved
+1.4% vs TC avg
Strong +23% interview lift
Without
With
+23.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 6m
Avg Prosecution
33 currently pending
Career history
69
Total Applications
across all art units

Statute-Specific Performance

§103
62.2%
+22.2% vs TC avg
§102
26.5%
-13.5% vs TC avg
§112
11.3%
-28.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 36 resolved cases

Office Action

§103
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 . Response to Arguments Applicant's election with traverse of Group I, claims 1-10, 16-20 in the reply filed on December 1, 2025 is acknowledged. The traversal is on the ground(s) that: (i) the process as claimed (Group II) may be used to make a permanent magnet rotor as claimed in claim 1 (Group I); and (ii) the subject matter of the Groups is sufficiently related that a thorough search for the subject matter of one of the Groups would encompass a search for the subject matter of the other Group. This is not found persuasive because: With respect to applicant’s argument (i), it is noted that all the ordered method steps in Group II are not recited in Group I. Therefore, the examiner contends that the process as claimed (Group II) is not used to make only a permanent magnet rotor as claimed in claim 1 (Group I). It may be used to make other permanent magnet rotors which are different from a permanent magnet rotor as claimed in claim 1 (Group I). With respect to applicant’s argument (ii), each Group requires a different field of search (e.g., searching different classes/subclasses or electronic resources, or employing different search queries); and/or the prior art applicable to one species would not likely be applicable to another species. The requirement is still deemed proper and is therefore made FINAL. 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. The factual inquiries 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. Claims 1-6, and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Zhang (CN 110445274) and in view of Goig (FR 2503950), Neubauer (DE 102015203995), Yamauchi (JP 2022159610), and Tschida (US 20200244114). As to claim 1, Zhang discloses a permanent magnet rotor for a motor, the rotor comprising: a generally cylindrical outer section and a bearing section arranged radially inwards of the generally cylindrical outer section for rotatably supporting the rotor (Fig. 2), wherein the generally cylindrical outer section and the bearing section are connected by a generally radially extending cover wall (Fig. 2), wherein the generally cylindrical outer section, the bearing section and the generally radially extending cover wall define at least partly a space for receiving a stator (Fig. 2), the generally cylindrical outer section comprising: an annular ring of a magnetic material (Fig. 7), a plurality of annularly disposed magnets arranged radially inwards of said annular ring (Fig. 7), wherein each magnet has a first and a second end in a circumferential direction (Fig. 7). PNG media_image1.png 391 520 media_image1.png Greyscale PNG media_image2.png 483 547 media_image2.png Greyscale Zhang fails to disclose (i) an inner wall arranged radially inwards of said plurality of magnets, the inner wall having a substantially cylindrical inner surface, wherein a thickness of the inner wall is substantially constant in the central section and increases in the first and second end sections towards the first and second ends of the magnet respectively, (ii) a first and second tapered end sections in the circumferential direction, (iii) and each magnet is provided with a radially inwards facing surface having a central section, (iv) wherein the inner wall is formed by overmolding the plurality of magnets with a polymer material. Goig, however, discloses an inner wall arranged radially inwards of said plurality of magnets (Fig. 2), the inner wall having a substantially cylindrical inner surface, wherein a thickness of the inner wall is substantially constant in the central section and increases in the first and second end sections towards the first and second ends of the magnet respectively (Fig. 3). PNG media_image3.png 327 256 media_image3.png Greyscale PNG media_image4.png 464 443 media_image4.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with an inner wall arranged radially inwards of said plurality of magnets, the inner wall having a substantially cylindrical inner surface, wherein a thickness of the inner wall is substantially constant in the central section and increases in the first and second end sections towards the first and second ends of the magnet respectively, as disclosed by Goig, in order to better secure the magnets. Neubauer, however, discloses a first and second tapered end sections in the circumferential direction (Fig. 2). PNG media_image5.png 384 476 media_image5.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with a first and second tapered end sections in the circumferential direction, as disclosed by Neubauer, to ease assembly of the magnet assembly. Yamauchi, however, discloses each magnet is provided with a radially inwards facing surface having a central section (Fig. 2). PNG media_image6.png 408 404 media_image6.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with each magnet is provided with a radially inwards facing surface having a central section, as disclosed by Yamauchi, to enhance magnetic strength. Tschida, however, discloses the inner wall is formed by overmolding the plurality of magnets with a polymer material (Para 0025). Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with the inner wall is formed by overmolding the plurality of magnets with a polymer material, as disclosed by Tschida, to better position the plurality of magnets. As to claim 2, the combination of Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 1, wherein the central section of the magnet extends over at least 40% of the magnet in the circumferential direction (Fig. 2 of Neubauer). PNG media_image7.png 409 489 media_image7.png Greyscale As to claim 3, the combination of Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 1, wherein the first tapered end section extends over at least 10% of the magnet in the circumferential direction (Fig. 2 of Neubauer). PNG media_image8.png 419 491 media_image8.png Greyscale As to claim 4, the combination of Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 1, wherein the bearing section comprises a bearing sleeve of metal for receiving an outer bearing race (Fig. 3 and 4 of Zhang). PNG media_image9.png 583 384 media_image9.png Greyscale PNG media_image10.png 354 448 media_image10.png Greyscale As to claim 5, the combination of Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 1, wherein the bearing section comprises an outer bearing race (fig. 3 of Zhang). PNG media_image9.png 583 384 media_image9.png Greyscale As to claim 6, the combination of Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 4, wherein the annular ring, the plurality of magnets and the bearing sleeve are overmolded in one step by a polymer, wherein the generally radially extending cover wall is formed out of the polymer in the same step (Para 0025 of Tschida). As to claim 8, the combination of Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 8, wherein the generally radially extending cover wall is formed free of metallic reinforcement (Fig. 4 of Goig). PNG media_image11.png 255 306 media_image11.png Greyscale Claims 7 and 9 are rejected under 35 U.S.C. 103 as being unpatentable over Zhang, Goig, Neubauer, Yamauchi, Tschida and in view of Ron (EP 3926791). As to claim 7, the combination of Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 6, and overmolding. Zhang fails to disclose a plurality of metallic threaded inserts for attaching a fan provided in the radially extending cover wall, wherein the plurality of threaded inserts are fixed in the cover wall. Rona, however, discloses a plurality of metallic threaded inserts for attaching a fan provided in the radially extending cover wall, wherein the plurality of threaded inserts (138; Fig. 5) are fixed in the cover wall (Fig. 5; “the blades 301 of the fan may be supported directly on the rotor 320, for example by means of the holes 138 with bush 138a inside which respective screws 338 for fixing the blades to the rotor are fixed”). PNG media_image12.png 301 327 media_image12.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with a plurality of metallic threaded inserts for attaching a fan provided in the radially extending cover wall, wherein the plurality of threaded inserts are fixed in the cover wall, as disclose by Rona, to better secure a fan to the rotor. As to claim 9, the combination of Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 1, and the generally radially extending cover wall Zhang fails to disclose reinforcing ribs extending radially from the central opening in the cover wall to each of a plurality of metallic threaded inserts. Rona, however, discloses reinforcing ribs extending radially from the central opening in the cover wall to each of a plurality of metallic threaded inserts (130; Fig. 5; “the internal rear surface of the closing plate 130 may have a plurality of raised ribs 130, in the example eight ribs”). PNG media_image13.png 301 386 media_image13.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with reinforcing ribs extending radially from the central opening in the cover wall to each of a plurality of metallic threaded inserts, to reinforce and increase the mechanical strength of the structure (“designed to reinforce and increase the mechanical strength of the article”). Claims 10, and 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over Schmidt (US 20230412054) and in view of Zhang, Goig, Neubauer, Yamauchi, and Tschida. As to claim 10, Schmidt discloses a cooling fan motor, comprising: a stator including a stack of steel laminations and a plurality of coils arranged in circumferentially spaced slots in the steel laminations. Schmidt fails to disclose a permanent magnet rotor, the permanent magnet rotor including: a generally cylindrical outer section and a bearing section arranged radially inwards of the generally cylindrical outer section for rotatably supporting the rotor, wherein the generally cylindrical outer section and the bearing section are connected by a generally radially extending cover wall, wherein the generally cylindrical outer section, the bearing section and the generally radially extending cover wall define at least partly a space for receiving a stator, the generally cylindrical outer section comprising: an annular ring of a magnetic material, a plurality of annularly disposed magnets arranged radially inwards of said annular ring and an inner wall arranged radially inwards of said plurality of magnets, the inner wall having a substantially cylindrical inner surface, wherein each magnet has a first and a second end in a circumferential direction and is provided with a radially inwards facing surface having a central section and first and second tapered end sections in the circumferential direction, wherein a thickness of the inner wall is substantially constant in the central section and increases in the first and second end sections towards the first and second ends of the magnet respectively, wherein the inner wall is formed by overmolding the plurality of magnets with a polymer material. Zhang, however, discloses a permanent magnet rotor, the permanent magnet rotor including: a generally cylindrical outer section and a bearing section arranged radially inwards of the generally cylindrical outer section for rotatably supporting the rotor (Fig. 2), wherein the generally cylindrical outer section and the bearing section are connected by a generally radially extending cover wall (Fig. 2), wherein the generally cylindrical outer section, the bearing section and the generally radially extending cover wall define at least partly a space for receiving a stator (Fig. 2), the generally cylindrical outer section comprising: an annular ring of a magnetic material (Fig. 7), a plurality of annularly disposed magnets arranged radially inwards of said annular ring (Fig. 7), wherein each magnet has a first and a second end in a circumferential direction (Fig. 7). PNG media_image1.png 391 520 media_image1.png Greyscale PNG media_image2.png 483 547 media_image2.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the motor of Schmidt with a permanent magnet rotor, the permanent magnet rotor including: a generally cylindrical outer section and a bearing section arranged radially inwards of the generally cylindrical outer section for rotatably supporting the rotor, wherein the generally cylindrical outer section and the bearing section are connected by a generally radially extending cover wall, wherein the generally cylindrical outer section, the bearing section and the generally radially extending cover wall define at least partly a space for receiving a stator, the generally cylindrical outer section comprising: an annular ring of a magnetic material, a plurality of annularly disposed magnets arranged radially inwards of said annular ring, wherein each magnet has a first and a second end in a circumferential direction, as disclosed by Zhang, to convert electrical energy to mechanical enegery. Goig, however, discloses an inner wall arranged radially inwards of said plurality of magnets (Fig. 2), the inner wall having a substantially cylindrical inner surface, wherein a thickness of the inner wall is substantially constant in the central section and increases in the first and second end sections towards the first and second ends of the magnet respectively (Fig. 3). PNG media_image3.png 327 256 media_image3.png Greyscale PNG media_image4.png 464 443 media_image4.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with an inner wall arranged radially inwards of said plurality of magnets, the inner wall having a substantially cylindrical inner surface, wherein a thickness of the inner wall is substantially constant in the central section and increases in the first and second end sections towards the first and second ends of the magnet respectively, as disclosed by Goig, in order to better secure the magnets. Neubauer, however, discloses a first and second tapered end sections in the circumferential direction (Fig. 2). PNG media_image5.png 384 476 media_image5.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with a first and second tapered end sections in the circumferential direction, as disclosed by Neubauer, to ease assembly of the magnet assembly. Yamauchi, however, discloses each magnet is provided with a radially inwards facing surface having a central section (Fig. 2). PNG media_image6.png 408 404 media_image6.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with each magnet is provided with a radially inwards facing surface having a central section, as disclosed by Yamauchi, to enhance magnetic strength. Tschida, however, discloses the inner wall is formed by overmolding the plurality of magnets with a polymer material (Para 0025). Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the rotor of Zhang with the inner wall is formed by overmolding the plurality of magnets with a polymer material, as disclosed by Tschida, to better position the plurality of magnets. As to claim 16, the combination of Schmidt, Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 10, wherein the central section of the magnet extends over at least 40% of the magnet in the circumferential direction (Fig. 2 of Neubauer). PNG media_image7.png 409 489 media_image7.png Greyscale As to claim 17, the combination of Schmidt, Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 10, wherein the first tapered end section extends over at least 10% of the magnet in the circumferential direction (Fig. 2 of Neubauer). PNG media_image8.png 419 491 media_image8.png Greyscale As to claim 18, the combination of Schmidt, Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the rotor according to claim 10, wherein the annular ring, the plurality of magnets and the bearing sleeve are overmolded by a polymer (Para 0025 of Tschida). Claims 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Schmidt, Zhang, Goig, Neubauer, Yamauchi, Tschida and in view of Ron. As to claim 19, the combination of Schmidt, Zhang, Goig, Neubauer, Yamauchi, and Tschida discloses the motor according to claim 18, and overmolding. Schmidt fails to disclose a plurality of metallic threaded inserts for attaching a fan provided in the radially extending cover wall, wherein the plurality of threaded inserts are fixed in the cover wall. Rona, however, discloses a plurality of metallic threaded inserts for attaching a fan provided in the radially extending cover wall, wherein the plurality of threaded inserts (138; Fig. 5) are fixed in the cover wall (Fig. 5; “the blades 301 of the fan may be supported directly on the rotor 320, for example by means of the holes 138 with bush 138a inside which respective screws 338 for fixing the blades to the rotor are fixed”). PNG media_image12.png 301 327 media_image12.png Greyscale Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the motor of Schmidt with a plurality of metallic threaded inserts for attaching a fan provided in the radially extending cover wall, wherein the plurality of threaded inserts are fixed in the cover wall, as disclose by Rona, to better secure a fan to the rotor. As to claim 20, the combination of Schmidt, Zhang, Goig, Neubauer, Yamauchi, Tschida, and Rona discloses the motor according to claim 19, wherein the generally radially extending cover wall is provided with reinforcing ribs extending radially from the central opening in the cover wall to each of the plurality of metallic threaded inserts (130; Fig. 5 of Rona; “the internal rear surface of the closing plate 130 may have a plurality of raised ribs 130, in the example eight ribs”). PNG media_image13.png 301 386 media_image13.png Greyscale Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to ETHAN N VO whose telephone number is (571)270-7593. The examiner can normally be reached Mon-Fri 8:30am - 5pm. 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, Christopher M Koehler can be reached on 571 272 3560. 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. /ETHAN NGUYEN VO/ Examiner, Art Unit 2834 /CHRISTOPHER M KOEHLER/ Supervisory Patent Examiner, Art Unit 2834
Read full office action

Prosecution Timeline

Feb 08, 2024
Application Filed
Feb 05, 2026
Non-Final Rejection — §103 (current)

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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
69%
Grant Probability
93%
With Interview (+23.2%)
2y 6m
Median Time to Grant
Low
PTA Risk
Based on 36 resolved cases by this examiner. Grant probability derived from career allow rate.

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