Prosecution Insights
Last updated: April 19, 2026
Application No. 18/692,443

ROTOR AND ELECTRIC MOTOR

Non-Final OA §103
Filed
Mar 15, 2024
Examiner
TRUONG, THOMAS
Art Unit
2834
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Aichi Steel Corporation
OA Round
1 (Non-Final)
73%
Grant Probability
Favorable
1-2
OA Rounds
2y 9m
To Grant
89%
With Interview

Examiner Intelligence

Grants 73% — above average
73%
Career Allow Rate
920 granted / 1260 resolved
+5.0% vs TC avg
Strong +16% interview lift
Without
With
+16.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 9m
Avg Prosecution
41 currently pending
Career history
1301
Total Applications
across all art units

Statute-Specific Performance

§101
0.9%
-39.1% vs TC avg
§103
50.2%
+10.2% vs TC avg
§102
23.4%
-16.6% vs TC avg
§112
22.5%
-17.5% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1260 resolved cases

Office Action

§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 . 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. This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention. Claims 1-8 are rejected under 35 U.S.C. 103 as being unpatentable over Masuzawa et al. (US 2006/0170301 A1) in view of Honkura et al. (US 2005/0076974 A1). RE claim 1, Masuzawa teaches a rotor 2 (Fig.1 and ¶ 62) comprising: a main body 2 composed of a soft magnetic material (¶ 62); and a permanent magnet 1 provided inside or outside the main body 2, the permanent magnet 1 being a bonded magnet 1 (¶ 64) comprising a magnet powder and a binder resin that binds the magnet powder (¶ 76), the magnet powder including coarse powder having an average particle diameter of 40-200µm (see ¶ 87) and fine powder having an average particle diameter of 1-10 µm (¶ 89), the binder resin including a thermosetting resin (¶ 87), the bonded magnet 1 being joined to the main body 2 (Fig.1). Masuzawa does not expressively teaches: the bonded magnet including 87-96 mass% of the magnet powder relative to the bonded magnet as a whole, the coarse powder having a mass ratio of 60-90 mass% to a total of the coarse powder and the fine powder RE (i) above, while Masuzawa is silent to the exact range, in ¶ 61, Masuzawa disclosed the following: “…The amount of the binder is preferably 1-5 parts by mass, more preferably 1-4 parts by mass, per 100 parts by mass of the magnet powder” Magnet powder fraction = 100/ (100+ (1 to 5)) = 95% to 99%. The derived ranged overlapped with the claim ranged of 87-96%. Masuzawa suggests that the amount of magnet powder and thermosetting resins can be adjusted to optimize mechanical strength and magnetic characteristics (¶ 61). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Masuzawa by having the bonded magnet including 87-96 mass% of the magnet powder relative to the bonded magnet as a whole, as suggested by Masuzawa, for the same reasons as discussed above. Furthermore, it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233. RE (ii) above, in ¶ 67, Honkura teaches: coarse magnet powder = 50-87% of total weight fine magnet powder = 15-40% of total weight resin binder = 1-10% of total weight Coarse + Fine + Resin = 100% => Coarse + Fine = 90% - 99% Lowest possible coarse fraction: Coarse = 50%, Fine = 40%, Resin = 10% 50 / (50 + 40) = 55.6% Highest possible coarse fraction: Coarse = 84%, Fine = 15%, Resin = 1% 84 / (84 + 15) = 84.8% The coarse powder is in the range of 55.6-84.8% of total magnet powder. Honkura further suggests that such configuration shows outstanding initial magnetic properties heat resistance with extremely low aging loss even when used in high temperature environments. In other words, the bonded magnet of the present invention exhibits high magnetic properties stable over a long period of time (¶ 68). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Masuzawa by having the coarse powder having a mass ratio of 60-90 mass% to a total of the coarse powder and the fine powder, as suggested by Honkura, for the same reasons as discussed above. Furthermore, it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233. RE claim 2/1, Masuzawa in view of Honkura has been discussed above. Masuzawa does not teach the bonded magnet has a resin layer with an average thickness of 0.1-5 µm in a vicinity of a joint interface with the main body. Honkura suggests that surface resin layer can be in the range of 0.5 – 2 µm (see ¶ 179, 180 which range is overlapped with the claimed range of 0.1-5 µm). The thickness of the resin can be adjusted to optimize the bonding of binder resin and anisotropic magnet powder is strengthened (¶ 178). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Masuzawa by having the bonded magnet has a resin layer with an average thickness of 0.1-5 µm in a vicinity of a joint interface with the main body, as suggested by Honkura, for the same reasons as discussed above. RE claim 3/1, Masuzawa in view of Honkura has been discussed above. Masuzawa further teaches the thermosetting resin is an epoxy resin (¶ 92). RE claim 4/1, Masuzawa in view of Honkura has been discussed above. Masuzawa further teaches the coarse powder includes NdFeB-based magnet powder whose basic components are Nd, Fe, and B (¶ 120). Masuzawa does not teach the fine powder includes SmFeN-based magnet powder whose basic components are Sm, Fe, and N and/or SmCo-based magnet powder whose basic components are Sm and Co Honkura teaches the fine powder includes SmFeN-based magnet powder whose basic components are Sm, Fe, and N (¶ 56) and/or SmCo-based magnet powder whose basic components are Sm and Co, doing so provided rare-earth anisotropic bonded magnet which naturally has excellent initial magnetic properties, and exhibits ample heat resistance (irreversible loss properties) the same or greater than bonded magnets that use Co-containing anisotropic magnet powder. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Masuzawa by having the fine powder includes SmFeN-based magnet powder whose basic components are Sm, Fe, and N and/or SmCo-based magnet powder whose basic components are Sm and Co, as taught by Honkura, for the same reasons as discussed above. RE claim 5/1, Masuzawa in view of Honkura has been discussed above. Masuzawa further teaches the bonded magnet 1 is formed by compression molding (¶ 124). RE claim 6/1, Masuzawa in view of Honkura has been discussed above. Masuzawa further teaches the main body 2 is composed of a stack of electromagnetic steel sheets (¶ 63). RE claim 7/1, Masuzawa in view of Honkura has been discussed above. Masuzawa further teaches an electric motor (Fig.14 and ¶ 1) comprising the rotor according to claim 1 and a stator 13 corresponding to the rotor (¶ 121 and Fig.14). RE claim 8/7, Masuzawa in view of Honkura has been discussed above. Masuzawa further teaches the rotor is an interior magnet type (Fig.14) in which the bonded magnet is integrally compression-molded inside the main body (¶ 124). Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Masuzawa in view of Honkura as applied to claim 1 above, and further in view of Fatemi et al. (US 2018/0358876 A1). RE claim 9/8, Masuzawa has been discussed above. Masuzawa does not teach the rotor has a maximum rotational speed of 20,000 rpm or more. Fatemi evidenced that it is well-known for rotor to be able to have maximum rotational speed of 20,000 rpm or more (¶ 100) when applicable to increase power factor, minimize magnet usage, and at the same time to meet stress requirement (¶ 100). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Masuzawa by having the rotor has a maximum rotational speed of 20,000 rpm or more, as taught by Fatemi, for the same reasons as discussed above. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to THOMAS TRUONG whose telephone number is (571)270-5532. The examiner can normally be reached Monday-Friday 9AM-6PM EST. 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, Seye Iwarere can be reached at (571) 270-5112. 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. /THOMAS TRUONG/Primary Examiner, Art Unit 2834
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Prosecution Timeline

Mar 15, 2024
Application Filed
Jan 08, 2026
Non-Final Rejection — §103 (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

1-2
Expected OA Rounds
73%
Grant Probability
89%
With Interview (+16.2%)
2y 9m
Median Time to Grant
Low
PTA Risk
Based on 1260 resolved cases by this examiner. Grant probability derived from career allow rate.

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