Office Action Predictor
Last updated: April 16, 2026
Application No. 18/689,719

ROTOR CORE, ROTOR, AND ROTARY ELECTRIC MACHINE

Non-Final OA §103
Filed
Mar 06, 2024
Examiner
STOUT, RILEY OWEN
Art Unit
2834
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Nippon Steel Corporation
OA Round
1 (Non-Final)
75%
Grant Probability
Favorable
1-2
OA Rounds
2y 7m
To Grant
78%
With Interview

Examiner Intelligence

Grants 75% — above average
75%
Career Allow Rate
86 granted / 115 resolved
+6.8% vs TC avg
Minimal +3% lift
Without
With
+2.8%
Interview Lift
resolved cases with interview
Typical timeline
2y 7m
Avg Prosecution
35 currently pending
Career history
150
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
54.8%
+14.8% vs TC avg
§102
35.0%
-5.0% vs TC avg
§112
8.9%
-31.1% vs TC avg
Black line = Tech Center average estimate • Based on career data from 115 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 . 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 34 is rejected under 35 U.S.C. 103 as being unpatentable over Oikawa et al (US 11190069 B2) in view of Sakai et al (US 20090261679 A1). With respect to claim 34, Oikawa teaches a rotor core comprising a soft magnetic material portion formed using a soft magnetic material (col. 8, ln. 40-44 “The rotor core 5B is made of a core material that is a soft magnetic material, specifically, is formed by stacking a plurality of electromagnetic steel sheets. The thickness of the electromagnetic steel sheets is generally from 0.1 mm to 0.7 mm.”), and having at least one magnet hole per one pole (fig. 11, pole center 62), wherein: the soft magnetic material portion has a recess portion in an outer peripheral surface (fig. 11, second region 3CB); the magnet hole has a first end portion and a second end portion in a left-right direction perpendicular to a magnetization direction of a permanent magnet installed through the magnet hole and a direction parallel to a rotation axis line serving as a center of rotation (fig. 11, second region 3CB); at least one end portion of the first end portion and the second recess portion is an opened open end portion (col. 11, 1-3 “One second region 3CB1 of the two second regions 3CB of each magnet insertion hole 1C of the first rotor core 5-1 is open to the outer peripheral surface 51 of the rotor core 5,”); Oikawa does not teach “the recess portion is in a position different from the open-end portion; and the recess portion is in a position opposite apart from teeth different from teeth having a lowest magnetic flux density of teeth of the stator core installed in a position opposite apart from the outer peripheral surface of the rotor core.” Sakai teaches the recess portion is in a position different from the open-end portion (fig. 8, recess 12); and the recess portion is in a position opposite apart from teeth different from teeth having a lowest magnetic flux density of teeth of the stator core installed in a position opposite apart from the outer peripheral surface of the rotor core (paragraph 51 “According to the present invention, the iron core section is provided with the recess 12, to change the magnetic flux in the air gap 6, thereby decreasing the radial electromagnetic force.” The Examiner is interpreting the decrease in radial electromagnetic force as having lower flux density.). It would have been obvious to one of ordinary skill, in the art at the time of filing, to combine the rotor and flux barriers of Oikawa with the recess of Sakai in order to better shape the magnetic flux of the rotor thereby increasing its torque. Allowable Subject Matter Claims 19-33 and 35-37 are allowed. The following is an examiner’s statement of reasons for allowance: With respect to claim 19, the limitation “in the cross section, the reference position relative to the magnet hole having the open end portion is a position at an intersection point of a straight line passing through a permanent-magnet reference end portion which is one of end portions of the permanent magnet at a position closest to the open end portion in the permanent magnet installed through the magnet hole, and the rotation axis line, and, the outer peripheral surface of the rotor core; in the cross section, the permanent-magnet reference end portion of the permanent magnet at the position closest to the open end portion is, of end portions of the permanent magnet, an end at a position at a farthest distance in the circumferential direction from a straight line passing through a central position in the circumferential direction of a region of one pole including the permanent magnet, and the rotation axis line; and the distance in the circumferential direction from a straight line passing through the central position in the circumferential direction of the region in one pole including the permanent magnet at the position closest to the open end portion, and the rotation axis line is a distance defined on a side, of the front side and the rear side in the rotation direction of the rotor core, in which the open end portion is present” in combination disclosed are neither anticipated nor obvious over the prior art. The closest available prior art is Oikawa et al (US 11190069 B2) in view of Takemoto et al (US 20120091845 A1). Oikawa teaches a rotor core comprising a soft magnetic material portion formed using a soft magnetic material (col. 8, ln. 40-44 “The rotor core 5B is made of a core material that is a soft magnetic material, specifically, is formed by stacking a plurality of electromagnetic steel sheets. The thickness of the electromagnetic steel sheets is generally from 0.1 mm to 0.7 mm.”), and having at least one magnet hole per one pole (figs. 11-12, five magnet insertion holes 1C-d), wherein: the magnet hole has, relative to a permanent magnet installed through the magnet hole, a space serving as a front-side flux barrier (fig. 11, second region 3CB) and a space serving as a rear-side flux barrier on both sides in a left-right direction perpendicular to a magnetization direction of the permanent magnet and a direction parallel to a rotation axis line serving as a center of rotation (fig. 11, second region 3CB); the space serving as at least one flux barrier, of the space serving as the front-side flux barrier and the space serving as the rear-side flux barrier, has an open end portion opened in an outer peripheral surface of the rotor core (fig. 13, each barrier is partially open to the outer periphery, see figure marked below.); in a cross section perpendicular to the rotation axis line, the front-side flux barrier is on a front side in a rotation direction of the rotor core than the rear-side flux barrier (Fig. 11, second region 3CB). PNG media_image1.png 444 518 media_image1.png Greyscale Oikawa Figure 13 Oikawa does not teach “in the cross section, a position of an open-end front-side corner portion of at least one of the open end portions provided in a same pole of a rotor is on a rear side in a rotation direction of the rotor core further than a reference position relative to the magnet hole having the open end portion; in the cross section, the open-end front-side corner portion is a corner portion on a front side in the rotation direction of the rotor core, of two corner portions in a circumferential direction of the rotor core, of at least one of the open end portions provided in the same pole of the rotor; in the cross section, the reference position relative to the magnet hole having the open end portion is a position at an intersection point of a straight line passing through a permanent-magnet reference end portion which is one of end portions of the permanent magnet at a position closest to the open end portion in the permanent magnet installed through the magnet hole, and the rotation axis line, and, the outer peripheral surface of the rotor core; in the cross section, the permanent-magnet reference end portion of the permanent magnet at the position closest to the open end portion is, of end portions of the permanent magnet, an end at a position at a farthest distance in the circumferential direction from a straight line passing through a central position in the circumferential direction of a region of one pole including the permanent magnet, and the rotation axis line; and the distance in the circumferential direction from a straight line passing through the central position in the circumferential direction of the region in one pole including the permanent magnet at the position closest to the open end portion, and the rotation axis line is a distance defined on a side, of the front side and the rear side in the rotation direction of the rotor core, in which the open end portion is present.” Takemoto teaches in the cross section, a position of an open-end front-side corner portion of at least one of the open end portions provided in a same pole of a rotor is on a rear side in a rotation direction of the rotor core further than a reference position relative to the magnet hole having the open end portion (see figure 2 marked below, reference position to right of open-end front side corner portion); in the cross section, the open-end front-side corner portion is a corner portion on a front side in the rotation direction of the rotor core (see figure 2 marked below), of two corner portions in a circumferential direction of the rotor core, of at least one of the open end portions provided in the same pole of the rotor (see figure 2 marked below). PNG media_image2.png 663 928 media_image2.png Greyscale Takemoto Figure 2 However, the prior art, exemplified by Oikawa in view of Takemoto, fails to teach, alone or in obvious combination “in the cross section, the reference position relative to the magnet hole having the open end portion is a position at an intersection point of a straight line passing through a permanent-magnet reference end portion which is one of end portions of the permanent magnet at a position closest to the open end portion in the permanent magnet installed through the magnet hole, and the rotation axis line, and, the outer peripheral surface of the rotor core; in the cross section, the permanent-magnet reference end portion of the permanent magnet at the position closest to the open end portion is, of end portions of the permanent magnet, an end at a position at a farthest distance in the circumferential direction from a straight line passing through a central position in the circumferential direction of a region of one pole including the permanent magnet, and the rotation axis line; and the distance in the circumferential direction from a straight line passing through the central position in the circumferential direction of the region in one pole including the permanent magnet at the position closest to the open end portion, and the rotation axis line is a distance defined on a side, of the front side and the rear side in the rotation direction of the rotor core, in which the open end portion is present.” Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.” Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to RILEY OWEN STOUT whose telephone number is (571)272-0068. The examiner can normally be reached Monday-Friday 7:30-5:30pm 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, Christopher M Koehler can be reached at (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. /R.O.S./Examiner, Art Unit 2834 /CHRISTOPHER M KOEHLER/Supervisory Patent Examiner, Art Unit 2834
Read full office action

Prosecution Timeline

Mar 06, 2024
Application Filed
Feb 20, 2026
Non-Final Rejection — §103
Apr 06, 2026
Response Filed

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
75%
Grant Probability
78%
With Interview (+2.8%)
2y 7m
Median Time to Grant
Low
PTA Risk
Based on 115 resolved cases by this examiner. Grant probability derived from career allow rate.

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