Prosecution Insights
Last updated: April 19, 2026
Application No. 18/704,453

ROTOR ASSEMBLY, AND SYNCHRONOUS MACHINE INCLUDING THE ROTOR ASSEMBLY

Non-Final OA §103
Filed
Apr 24, 2024
Examiner
KENERLY, TERRANCE L
Art Unit
2834
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Mahle International GmbH
OA Round
1 (Non-Final)
73%
Grant Probability
Favorable
1-2
OA Rounds
2y 8m
To Grant
88%
With Interview

Examiner Intelligence

Grants 73% — above average
73%
Career Allow Rate
828 granted / 1129 resolved
+5.3% vs TC avg
Strong +15% interview lift
Without
With
+15.1%
Interview Lift
resolved cases with interview
Typical timeline
2y 8m
Avg Prosecution
33 currently pending
Career history
1162
Total Applications
across all art units

Statute-Specific Performance

§101
1.2%
-38.8% vs TC avg
§103
55.7%
+15.7% vs TC avg
§102
28.8%
-11.2% vs TC avg
§112
11.2%
-28.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1129 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. 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. Claim(s) 12-15, 17, 20, 21, and 26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. (CN 111769673) in view of Trommer (US 4570094) and Ikuta et al. (US 20060208581). 12. Chen et al. teach: A rotor assembly 100 for an inductively electrically excited synchronous machine (since it is inductive excited by rotor transformer 2112, MPEP 2112), comprising: a hollow shaft 11 rotatable about an axis of rotation; a rotor 12 connected in a rotationally fixed manner to the hollow shaft (fig 9); a secondary-side circuit 212 of an energy transmitter, the secondary-side circuit arranged in/with/by/via a rotationally fixed manner in the rotor assembly (fig 9); the secondary-side circuit including a rectifier (since the secondary-side circuit is a rectifier plate 212, the rectifier is included on the plate, MPEP 2112), the rectifier including a printed circuit board (since the rectifier is on the plate with electrical connections, the plate is inherently a printed circuit board) and at least one electrical component part (diodes of the rectifier connected to the rectifying plate 212, excerpt below) fastened to the printed circuit board and a secondary coil 2112; the rectifier is aligned transversely to the axis of rotation; but does not teach that i) the rectifier is arranged in a rotationally fixed manner in a cavity of the hollow shaft; and ii) the rectifier further includes a cooling body of a heat-conducting material, the cooling body abutting against the printed circuit board of the rectifier such that the cooling body faces away from the at least one electrical component part and transmits heat. PNG media_image1.png 485 818 media_image1.png Greyscale Trommer teaches that i) the rectifier 22 is arranged in a rotationally fixed manner in a cavity of the hollow shaft 30 (fig 1) to reduce the axial size of the rotor assembly (since the rectifier is inside of the shaft). PNG media_image2.png 661 740 media_image2.png Greyscale As a result, it would have been obvious to a person having ordinary skill in the art prior to the invention of Chen et al. being effectively filed to modify it so that i) the rectifier is arranged in a rotationally fixed manner in a cavity of the hollow shaft, as taught by Trommer so as to reduce the axial size of the rotor assembly. Ikuta et al. teach that ii) the rectifier 12 further includes a cooling body 24 of a heat-conducting material, the cooling body abutting against the printed circuit board of the rectifier 27 (fig 4) such that the cooling body faces away (see the fins 24b) from the at least one electrical component part and transmits heat to direct heat away from the rectifying unit which prolongs the service life of the rectifying unit. PNG media_image3.png 623 690 media_image3.png Greyscale As a result, it would have been obvious to a person having ordinary skill in the art prior to the invention of Chen et al. being effectively filed to modify it such that ii) the rectifier further includes a cooling body of a heat-conducting material, the cooling body abutting against the printed circuit board of the rectifier such that the cooling body faces away from the at least one electrical component part and transmits heat as taught by Ikuta et al. so as to prolong the service life of the rectifier. 13. Chen et al. teach: The rotor assembly according to claim 12, wherein the at least one electrical component part of the rectifier is mechanically supported on the hollow shaft (fig 9). 14. Chen et al. in view of Trommer and Ikuta et al. teach: The rotor assembly according to claim 12, wherein: the hollow shaft (of Trommer) is formed of a shaft end (at ref 32 of Trommer, fig 1) and a shaft cover 32 axially closing the shaft end (fig 1); and the rectifier is firmly connected to at least one of the shaft end and the shaft cover of the hollow shaft (see Trommer fig 1 above). 15. Chen et al. in view of Trommer and Ikuta et al. teach: The rotor assembly according to claim 12, wherein the at least one electrical component part of the rectifier (of Chen et al.) is encapsulated with a heat-conducting casting compound 213 (Chen et al. does not teach the specific thermal conductivity of the potting adhesive. However this potting compound conducts some heat to some degree, MPEP 2112). 17. Chen et al. in view of Trommer and Ikuta et al. teach: The rotor assembly according to claim 12, wherein the cooling body (of Ikuta et al.) includes a cooling structure (fins 24b of Ikuta et al.) facing away from the printed circuit board (of Ikuta et al.) (Ikuta et al. fig 4 above). 20. Chen et al. teach: The rotor assembly according to claim 12, wherein the secondary coil of the secondary-side circuit is arranged at least one of in the cavity of the hollow shaft and outside of the cavity of the hollow shaft such that the secondary coil is interactable inductively with a primary-side circuit of the energy transmitter (Chen et al. fig above). 21. Chen et al. in view of Trommer and Ikuta et al. teach: An inductively electrically excited synchronous machine (Chen et al. fig 18), comprising: the rotor assembly according to claim 12; a stator assembly 10 (of Trommer) including a stator 10 (of Trommer); the rotor assembly 12 (of Trommer) received in the stator such that the rotor assembly is rotatable about the axis of rotation (Trommer fig 1); the stator assembly including a primary-side circuit 26 (of Trommer ) of the energy transmitter; the primary-side circuit arranged in a rotationally fixed manner in the stator assembly (since it is a part of the stator); wherein the primary-side circuit includes an inverter (inherent, MPEP 2112) and a primary coil 26 (of Trommer); and wherein the primary coil and the secondary coil 24 (of Trommer) are arranged such that the primary coil and the secondary coil are interactable with one another inductively (Trommer fig 1). PNG media_image4.png 669 774 media_image4.png Greyscale 26. Chen et al. in view of Trommer and Ikuta et al. teach: The rotor assembly according to claim 17, wherein the cooling structure includes at least one of (i) at least one cooling rib 24b (of Ikuta et al.) and (ii) a plurality of cooling pins. Claim(s) 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. in view of Trommer and Ikuta et al. and in further view of Hinard et al. (FR 2963199). 16. Chen et al. in view of Trommer and Ikuta et al. has been discussed above, re claim 12; but does not teach that the cooling body is electrically insulated from the hollow shaft via a dielectric sheathing. Hinard et al. teach that a dielectric 34 electrically insulates the cooling body 40 from a pcb 30 prevents an electrical short between the cooling body and the pcb which prolongs the life of the cooling body. The person having ordinary skill in the art would apply the same technique to (instead of a PCB) the hollow shaft of Chen et al. for the same benefit. Consequently, it would have been obvious to a person having ordinary skill in the art prior to the invention of Chen et al. being effectively filed to modify it such that the cooling body is electrically insulated from the hollow shaft via a dielectric sheathing, as taught by Hinard et al. so as to prolong the life of the cooling body. Claim(s) 22 & 23 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. in view of Trommer and Ikuta et al. and Dobler et al. (US 20150051671). 22. Chen et al. in view of Trommer and Ikuta et al. has been discussed above, re claim 12; but does not teach that the at least one electrical component part of the rectifier is connected to the printed circuit board via a heat-conducting heat conduction pad so as to transmit heat. Dobler et al. teach that the at least one electrical component part/diode 122 of the rectifier (of Chen et al. in view of Trommer and Ikuta et al.) is connected to the printed circuit board 110 via a heat-conducting heat conduction pad 130 so as to transmit heat which prolongs the life of the electrical component part. Consequently, it would have been obvious to a person having ordinary skill in the art prior to the invention of Chen et al. being effectively filed to modify it such that the at least one electrical component part of the rectifier is connected to the printed circuit board via a heat-conducting heat conduction pad so as to transmit heat, as taught by Dobler et al. so as to prolong the life of the electrical component part. 23. Chen et al. in view of Trommer and Ikuta et al. has been discussed above, re claim 12; but does not teach that the at least one printed circuit board of the rectifier is connected to the cooling body via a heat-conducting heat conduction pad so as to transmit heat. Dobler et al. teach that the at least one electrical component part/diode 122 of the rectifier (of Chen et al. in view of Trommer and Ikuta et al.) is connected to the printed circuit board 110 via a heat-conducting heat conduction pad 130 so as to transmit heat which prolongs the life of the electrical component part. The person having ordinary skill in the art would be motivated to use the same technique of having the heat conduction pad between the PCB and the cooling body for the same benefit for the PCB since the PCB and electrical components emit heat. Consequently, it would have been obvious to a person having ordinary skill in the art prior to the invention of Chen et al. being effectively filed to modify it such that the at least one printed circuit board of the rectifier is connected to the cooling body via a heat-conducting heat conduction pad so as to transmit heat, as taught by Dobler et al. so as to prolong the life of the PCB. Claim(s) 24 & 25 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. in view of Trommer and Ikuta et al. and in further view of Ting et al. (US 5389400). 24. Chen et al. in view of Trommer and Ikuta et al. has been discussed above, re claim 24; but does not teach that the cooling body is formed from a dielectric material. Ting et al. teach that the cooling body 10 is formed from a dielectric material 12 to improve electrical and thermal performance of the cooling body (col 3 5th para). Consequently, it would have been obvious to a person having ordinary skill in the art prior to the invention of Chen et al. being effectively filed to modify it such that the cooling body is formed from a dielectric material, as taught by Ting et al. so as to improve electrical and thermal performance of the cooling body. 25. Chen et al. in view of Trommer and Ikuta et al. has been discussed above, re claim 12; but does not teach that the dielectric material is a composite material. Ting et al. teach that the dielectric material is a composite material 12 to improve electrical and thermal performance of the cooling body (col 3 5th para). Consequently, it would have been obvious to a person having ordinary skill in the art prior to the invention of Chen et al. being effectively filed to modify it such that the dielectric material is a composite material, as taught by Ting et al. so as to improve electrical and thermal performance of the cooling body. Allowable Subject Matter Claims 27-31 are allowed. The following is an examiner’s statement of reasons for allowance: The primary reason for allowing claim 27 is that the rectifier of prior art does not divide the cavity of the hollow shaft into a transmission chamber and cooling chamber. The closest prior art was Chen et al., Trommer, and Ikuta et al.. Neither of these references taken separately or in an combination anticipate/make obvious the aforementioned limitations. Claims 28-31 depend from claim 27 directly/indirectly and are likewise allowed. 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.” Claims 18 and 19 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. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to TERRANCE L KENERLY whose telephone number is (571)270-7851. The examiner can normally be reached M-F 9am-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 Koehler can be reached at 5712723560. 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. /TERRANCE L KENERLY/Primary Examiner, Art Unit 2834
Read full office action

Prosecution Timeline

Apr 24, 2024
Application Filed
Feb 05, 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
88%
With Interview (+15.1%)
2y 8m
Median Time to Grant
Low
PTA Risk
Based on 1129 resolved cases by this examiner. Grant probability derived from career allow rate.

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