Prosecution Insights
Last updated: April 19, 2026
Application No. 18/704,914

ROTOR FOR AN EXTERNALLY EXCITED SYNCHRONOUS MACHINE

Non-Final OA §102
Filed
Apr 25, 2024
Examiner
COOK, CORTEZ M
Art Unit
2846
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Mahle International GmbH
OA Round
1 (Non-Final)
84%
Grant Probability
Favorable
1-2
OA Rounds
2y 2m
To Grant
92%
With Interview

Examiner Intelligence

Grants 84% — above average
84%
Career Allow Rate
412 granted / 489 resolved
+16.3% vs TC avg
Moderate +8% lift
Without
With
+7.9%
Interview Lift
resolved cases with interview
Typical timeline
2y 2m
Avg Prosecution
15 currently pending
Career history
504
Total Applications
across all art units

Statute-Specific Performance

§101
2.5%
-37.5% vs TC avg
§103
49.3%
+9.3% vs TC avg
§102
30.3%
-9.7% vs TC avg
§112
15.9%
-24.1% vs TC avg
Black line = Tech Center average estimate • Based on career data from 489 resolved cases

Office Action

§102
DETAILED ACTION This office action is in response to preliminary amendments filed on 04/25/2024. Claims 1-20 are pending. 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 . Priority Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55. Information Disclosure Statement The information disclosure statement (IDS) submitted on 04/25/2024 was filed on the filing date of the application. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner. Claim Rejections - 35 USC § 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. Claims 1-3, 5, 7-9, 12-13, 15, and 19-20 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Bulatow US 20200195104 A1 (Hereinafter “Bulatow”). Regarding Claim 1, Bulatow teaches a rotor for an externally excited synchronous machine ([0045], 12), comprising: rotor windings (Fig. 1, 18 & 30) arranged on a rotor shaft (Fig. 1, 20), a balancing ring (Fig. 1, 50), a rectifier (Fig. 1, 43) electrically connected to the rotor windings (Fig. 1, 18 & 30), wherein on the balancing ring a rotary transformer rotor of a rotary transformer (Fig. 1, 21) with a secondary coil (Fig. 3, SEC) is arranged, the rotary transformer rotor projects from the balancing ring in an axial direction ([0057] & [0085]). Regarding Claim 2, Bulatow teaches the rotor according to Claim 1, wherein the balancing ring, the rectifier and the secondary coil form a prefabricated assembly (Fig. 3, 50, 43, & SEC are attached to 31). Regarding Claim 3, Bulatow teaches the rotor according to Claim 2, wherein the secondary coil, the rectifier and the balancing ring are glued, welded, soldered, screwed, pressed, clipped and/or cast to/with one another ([0020]-[0022]). Regarding Claim 5, Bulatow teaches the rotor according to Claim 1,wherein the secondary coil is arranged annularly about a rotary axis of the hollow rotary shaft (Claim 13). Regarding Claim 7, Bulatow teaches the rotor according to Claim 1,wherein: at the face-end of the rotor windings, end windings are arranged, the rectifier and the balancing ring form a housing surrounding the end windings (Fig. 3, 50, 43, & SEC are attached to 31), wherein electronic components of the rectifier are arranged in a housing interior (Fig. 1, 24), and the rotor shaft is configured hollow and comprises a cooling channel for conducting coolant, which is communicatingly connected to the housing interior ([0065] & [0080]). Regarding Claim 8, Bulatow teaches an externally excited synchronous machine ([0045], 12), comprising an electrically energisable rotor (Fig. 1, 17) the rotor including: a rotor shaft (Fig. 1, 20) including rotor windings (Fig. 1, 18 & 30) arranged thereon, a balancing ring (Fig. 1, 50), a rectifier (Fig. 1, 43) electrically connected to the rotor windings, a rotary transformer (Fig. 1, 21) arranged on the balancing ring and including a rotary transformer rotor with a secondary coil (Fig. 3, SEC) arranged on the rotary transformer rotor, wherein the rotary transformer rotor projects from the balancing ring in an axial direction ([0057] & [0085]). Regarding Claim 9, Bulatow teaches the externally excited synchronous machine according to further comprising a rotary transformer stator with a primary coil (Fig. 1, 22) and a transformer core of a magnetic core material (Fig. 1, 38). Regarding Claim 12, Bulatow teaches the externally excited synchronous machine according to Claim 8, wherein the balancing ring, the rectifier and the secondary coil form a prefabricated assembly (Fig. 3, 50, 43, & SEC are attached to 31). Regarding Claim 13, Bulatow teaches the externally excited synchronous machine according to Claim 12, wherein the secondary coil, the rectifier and the balancing ring are glued, welded, soldered, screwed, pressed, clipped and/or cast to/with one another ([0020]-[0022]). Regarding Claim 15, Bulatow teaches the externally excited synchronous machine according to Claim 8, wherein the secondary coil is arranged annularly about a rotary axis of the hollow rotary shaft (Claim 13). Regarding Claim 19, Bulatow teaches the externally excited synchronous machine according to Claim 8, wherein end windings are arranged at a face-end of the rotor ([0059]). Regarding Claim 20, Bulatow teaches the externally excited synchronous machine according to Claim 19, wherein: the rectifier and the balancing ring form a housing surrounding the end windings (Fig. 3, 50, 43, & SEC are attached to 31), wherein electronic components of the rectifier are arranged in a housing interior (Fig. 1, 24), and the rotor shaft is configured hollow and comprises a cooling channel for conducting coolant, which is communicatingly connected to the housing interior ([0065] & [0080]). Allowable Subject Matter Claims 4, 6, 10-11, 14, and 16-18 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. Any inquiry concerning this communication or earlier communications from the examiner should be directed to CORTEZ M COOK whose telephone number is (571)270-7954. The examiner can normally be reached Monday-Thursday 7:30-5pm. 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, Eduardo Colon-Santana can be reached at 571-272-2060. 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. /CORTEZ M COOK/ Primary Examiner, Art Unit 2846
Read full office action

Prosecution Timeline

Apr 25, 2024
Application Filed
Jan 14, 2026
Non-Final Rejection — §102 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12603593
MOTOR CONTROL DEVICE
2y 5m to grant Granted Apr 14, 2026
Patent 12592662
ELECTRIC MACHINE DRIVE CALIBRATION, VERIFICATION, AND EFFICIENCY IMPROVEMENT
2y 5m to grant Granted Mar 31, 2026
Patent 12559161
STEERING INPUT DEVICE
2y 5m to grant Granted Feb 24, 2026
Patent 12562665
System And Method For Motor Control Through Improved Location Measurement
2y 5m to grant Granted Feb 24, 2026
Patent 12556048
METHOD FOR STARTING A ROTOR OF A CLAW POLE MOTOR
2y 5m to grant Granted Feb 17, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

1-2
Expected OA Rounds
84%
Grant Probability
92%
With Interview (+7.9%)
2y 2m
Median Time to Grant
Low
PTA Risk
Based on 489 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month