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 . This Office Action is responsive to the Applicant's communication filed February 13, 2026. In view of this communication and the amendment concurrently filed: claims 1-13 and 16-17 were previously pending; claim 4 was cancelled and no claims were added by amendment; and thus, claims 1-3, 5-13, and 16-17 are now pending in the application.
Response to Arguments
Applicant's arguments filed September 11, 2025 have been fully considered.
The Applicant's first point (Page 8 of Remarks) states that clarification is needed for the “direct axis” in NIGO. The Applicant than uses the direct axis on TANAKA as an example, the Examiner agrees with the Applicants understanding, and submits that that he use of “radial direction” was unclear. Therefore, the Examiner will more clearly illustrate the meaning of “direct axis” in NIGO.
The Applicant's second point (Page 9-10 of Remarks) argues that NIGO and cannot use the constriction point of TANAKA because combining them would not be not have been obvious to one ordinarily skilled in the art. Specifically, the Applicant regards the different orientations of the Transverse Axis between NIGO and TANAKA would be too complicated for one of ordinary skill to modify. The Examiner disagrees and believe this modification would be a simple rearrangement of parts; and since it has been held that rearranging parts of an invention involves only routine skill in the art. In re Japikse, 86 USPQ 70. Thus the 103 rejection is upheld.
The Applicant's third point (Page 11-12 of Remarks) argues that since NIGO and TANAKA have different shaped flux barriers it would not be obvious to modify NIGO by using the constriction point of TANAKA. The Applicant goes on to argue that it is not possible to change the shape of the extended portion of MNIGO without resulting in a shape change that meets the limitation of a “c-shape.” The Examiner disagrees with this logic and asserts that simple change of shape is obvious to one with ordinary skill in the art. Thus the 103 rejection is upheld.
Since the claims have been extensively amended, they necessitate a new grounds of rejection for claims 1-3, 5-6, 8, 11-13, and 16; claims 7, 9, 10, and 17 have been shown to be not obvious to combine and therefore contain allowable subject matter.
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(s) 1-3, 5-6, 8, and 12-13 is/are rejected under 35 U.S.C. 103 as being unpatentable over NIGO (US 20150256038 A1)in view of TANAKA (WO 2019215853 A1).
Regarding claim 1, NIGO teaches:
A rotor (Fig 2; 5) for an electric machine(Fig 1; 1), the rotor comprising: a plurality of rotor poles[0036], the rotor poles each comprising:
an aperture comprising(Fig 2; 21):
a chamber (Fig 3; 22) for receiving a magnet(Fig 2; 13); and
at least one flux barrier (Fig 2; 23)for controlling a path through which magnetic flux flows in the rotor[0039](the prior art teaches that flux barriers are used to prevent flux short circuit; it is commonly known to do this by redirecting flux);
wherein the rotor poles [0036] each have a direct axis (an axis spanning the radial direction) corresponding to a central radial axis of the rotor pole and each of the rotor poles [0036]comprise at least one flux guide (Fig 3; 11b) for guiding magnetic flux across the at least one flux barrier (Fig 3; 23)during a demagnetization event[0046], the or each flux guide (Fig 3; 11b)forming a constriction (Fig 3; Lc)between the chamber (Fig 3; 22)and the at least one flux barrier(Fig 3; 23).
a central longitudinal axis (Axial direction) of the chamber(Fig 3; 22) and a transverse axis (Fig 3; T1)of the chamber and a vertical axis (Fig 3; V1)of the chamber, the transverse axis (Fig 3; T1)and the vertical axis (Fig 3; V1)each perpendicular to the central longitudinal axis, the transverse axis (Fig 3; T1)perpendicular to the direct axis(an axis spanning the radial direction), and
wherein a first of the at least one flux barrier(Fig 3; 23a) disposed at a first end of the at least one aperture(Fig 3; 21 counter-clockwise); and a second of the at least one flux barrier (Fig 3; 23b)disposed at a second end of the at least one aperture(Fig 3; 21 clockwise), and wherein the chamber (Fig 3; 22) extends in a transverse manner from the first end to the second end along the transverse axis(shown in Fig 2/3), and wherein each of the first and the second of the at least one flux barrier (Fig 3; 23) is annular and has a C-shape(shown in Fig 3).
PNG
media_image1.png
459
574
media_image1.png
Greyscale
PNG
media_image2.png
445
512
media_image2.png
Greyscale
NIGO does not teach:
and wherein the or each flux guide is configured such that the constriction has a span which is smallest in a direction substantially perpendicular to a central longitudinal axis of the chamber.
TANAKA teaches:
and wherein the or each flux guide (Fig 1; 20) is configured such that the constriction (Fig 1; C1)has a span which is smallest in a direction substantially perpendicular to a central longitudinal axis (runs into the page of Fig 1) of the chamber (Fig 1; 2)and a transverse axis (Fig 1; T1)of the chamber (Fig 1; 2)and parallel to a vertical axis (Fig 1; V1)of the chamber(Fig 1; 2), the transverse axis (Fig 1; T1)and the vertical axis (Fig 1; V1)each perpendicular to the central longitudinal axis(runs into the page of Fig 1).
PNG
media_image3.png
892
835
media_image3.png
Greyscale
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 NIGO by using a flux guide that forms a constriction which runs parallel to the vertical axis of the chamber as taught by TANAKA in order to suppress higher-order components of magnet magnetic flux interlinking with the stator, so that iron loss can be reduced. [pg 1; ln 19-20 TANAKA].
Regarding claim 2, NIGO, in view of TANAKA, teaches the rotor as claimed in claim 1:
wherein the or each flux guide (Fig 3; 11b) comprises a projection (Fig 3; 11b’)extending partway across the aperture[0045-0046].
Regarding claim 3, NIGO, in view of TANAKA, teaches the rotor as claimed in claim 1:
wherein the or each flux guide (Fig 3; 11b) is disposed between the chamber(Fig 3; 22) and the at least one flux barrier(Fig 3; 23).
Regarding claim 4, NIGO, in view of TANAKA, teaches the rotor as claimed in claim 1:
wherein the at least one flux barrier (Fig 3; 23) is annular and has a C-shape(shown in Fig 3).
Regarding claim 5, NIGO, in view of TANAKA, teaches the rotor as claimed in claim 1.
NIGO does not teach:
wherein an extent of the or each flux guide is approximately 40% of a height of the chamber in a direction perpendicular to the transverse axis of the chamber and parallel to the vertical axis of the chamber
TANAKA teaches:
wherein an extent of the or each flux guide (Fig 1, 20’) is approximately 40% of a height of the chamber (Fig 1, 2)in a direction perpendicular to the transverse axis (Fig 1, T)of the chamber and parallel to the vertical axis (Fig 1, V1)of the chamber.
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 the first flux guild (20) of TANAKA by using the vertical height of the second flux guild (20’) as taught by TANAKA in order to firmly secure the magnet from slipping transversely from both ends.
Regarding claim 6, NIGO, in view of TANAKA, teaches the rotor as claimed in claim 1:
wherein the aperture (Fig 2; 21) is a first aperture, the chamber (Fig 3; 22) is a first chamber, the magnet (Fig 2; 13)is a first magnet, the at least one flux barrier (Fig 3; 23) is at least one first flux barrier, and the at least one flux guide (Fig 3; 11b)is at least one first flux guide.
NIGO does not teach:
wherein each rotor pole comprises a plurality of magnet layers, and the first aperture, the first chamber, the first magnet, the at least one first flux barrier, and the at least one first flux guide are arranged in a first magnet laver of the plurality of magnet layers.
TANAKA teaches:
wherein each rotor pole (Fig 1; 1) comprises a plurality of magnet layers(Fig 1 shows a layer structure made by A and B), and the first aperture(Fig 1; 2A), the first chamber(Fig 1; 2A), the first magnet(Fig 1; 3A), the at least one first flux barrier(Fig 1; 4A), and the at least one first flux guide (Fig 1; 20)are arranged in a first magnet laver (Fig 1; A/B) of the plurality of magnet layers.
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 NIGO by adding the layers as taught by TANAKA in order to improves the concentration effect of the magnetic flux.
Regarding claim 8, NIGO, in view of TANAKA, teaches the rotor as claimed in claim 1:
wherein one of the at least one flux guide(Fig 3; 11b1/2)is associated with each flux barrier(Fig 3; 23a/b).
Regarding claim 12, NIGO, in view of TANAKA, teaches the rotor as claimed in claim 1:
wherein the at least one flux barrier(Fig 3; 23) extends towards an outer circumference of the rotor(Fig 3; 5).
Regarding claim 13, NIGO teaches:
A rotor (Fig 2; 5) for an electric machine(Fig 1; 1), the rotor comprising: a plurality of rotor poles[0036], the rotor poles each comprising:
a first aperture comprising(Fig 2; 21):
a first chamber (Fig 3; 22) for receiving a first magnet(Fig 2; 13); and
at least one first flux barrier (Fig 2; 23)for controlling a path through which magnetic flux flows in the rotor[0039](the prior art teaches that flux barriers are used to prevent flux short circuit; it is commonly known to do this by redirecting flux); and
wherein the at least one first flux barrier (Fig 2; 23) is annular and has a C-shape (shown in Fig 3.)
wherein each of the rotor poles [0036]comprise at least one first flux guide (Fig 3; 11b) for guiding magnetic flux across the at least one first flux barrier (Fig 3; 23)during a demagnetization event[0046], the first flux guide (Fig 3; 11b)forming a constriction (Fig 3; Lc)between the first chamber (Fig 3; 22)and the at least one first flux barrier(Fig 3; 23).
a central longitudinal axis (Axial direction) of the first chamber(Fig 3; 22) and a transverse axis (Fig 3; T1)of the first chamber and a vertical axis (Fig 3; V1)of the first chamber, the transverse axis (Fig 3; T1)and the vertical axis (Fig 3; V1)each perpendicular to the central longitudinal axis.
NIGO does not teach:
wherein the first aperture is arranged in a first magnet laver of a plurality of magnet layers, a second magnet laver of the plurality of magnet layers comprising a pair of inclined second magnets accommodated in respective second apertures, the first aperture positioned intermediate the respective second apertures
and wherein the or each first flux guide is configured such that the constriction has a span which is smallest in a direction substantially perpendicular to a central longitudinal axis of the chamber.
TANAKA teaches:
wherein the first aperture (Fig 1; 2A)is arranged in a first magnet laver (Fig 1 shows aperture A and B making the first layer) of a plurality of magnet layers( there is a layer on each side of the direct axis), a second magnet laver of the plurality of magnet layers comprising a pair of inclined second magnets accommodated in respective second apertures, the first aperture positioned intermediate the respective second aperture(this structure is commonly known as the concentration effect of permanent magnet rotors and is shown in Fig 1 of TANAKA and Fig 2 of MICHAELIDES); and
and wherein the or each first flux guide (Fig 1; 20) is configured such that the constriction (Fig 1; C1)has a span which is smallest in a direction substantially perpendicular to a central longitudinal axis (runs into the page of Fig 1) of the first chamber (Fig 1; 2)and a transverse axis (Fig 1; T1)of the chamber (Fig 1; 2)and parallel to a vertical axis (Fig 1; V1)of the first chamber(Fig 1; 2), the transverse axis (Fig 1; T1)and the vertical axis (Fig 1; V1)each perpendicular to the central longitudinal axis(runs into the page of Fig 1).
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 NIGO by using a flux guide that forms a constriction which runs parallel to the vertical axis of the chamber as taught by TANAKA in order to suppress higher-order components of magnet magnetic flux interlinking with the stator, so that iron loss can be reduced. [pg 1; ln 19-20 TANAKA].
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 NIGO by adding the layers as taught by TANAKA in order to improves the concentration effect of the magnetic flux.
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over NIGO (US 20150256038 A1) in view of TANAKA (WO 2019215853 A1), in further view of MICHAELIDES (US 20190165627 A1).
In regards to claim 11, NIGO, in view of TANAKA, teaches the rotor as claimed in claim 1.
Combination NIGO/TANAKA does not teach:
rotor pole comprises a plurality of the apertures.
MICHAELIDES teaches:
wherein each rotor pole (Fig 2; 4) comprises a plurality of the apertures(Fig 2; 11/12/13)[0050-0051].
PNG
media_image4.png
721
598
media_image4.png
Greyscale
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 NIGO by using a plurality of apertures as taught by MICHAELIDES in order improved distribution of magnetic flux around the rotor [0007 MICHAELIDES].
Claim(s) 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over MICHAELIDES (US 20190165627 A1) in view of NIGO (US 20150256038 A1), in further view of TANAKA (WO 2019215853 A1).
In regards to claim 16, MICHAELIDES teaches:
A vehicle (Fig 1; 100) comprising the electric machine [0001] comprising a rotor (Fig 2; 10) comprising flux barriers (Fig 3; 13-1, 13-3 [0006]).
PNG
media_image5.png
322
297
media_image5.png
Greyscale
PNG
media_image6.png
460
405
media_image6.png
Greyscale
MICHAELIDES does not teach:
the rotor as claimed in claim 1.
Combination NIGO/TANAKA teaches:
an electric machine (Fig 1; 1) comprising the rotor (Fig 2; 5) as claimed in claim 1.
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 MICHAELIDES by using the rotor with flux barriers as taught by combination NIGO/TANAKA in claim 1, in order to suppress the demagnetization of the magnet in spite of including the flux barrier and the slit [0016 NIGO].
Allowable Subject Matter
Claims 7, 9, 10, and 17 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.
Regarding claim 9: The following is a statement of reasons for the indication of allowable subject matter:
The prior art teaches the limitations of the claims in one piece or another however it would not be obvious to combine the prior art to create the present invention.
Claims 7, 10, and 17 are objected to also as the depend from claim 9
As allowable subject matter has been indicated, applicant's reply must either comply with all formal requirements or specifically traverse each requirement not complied with. See 37 CFR 1.111(b) and MPEP § 707.07(a).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to NICHOLAS L SETZER whose telephone number is (571)272-3021. The examiner can normally be reached Mon-Fri, 8am-5pm 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, Oluseye 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.
/N.L.S./Examiner, Art Unit 2834
/OLUSEYE IWARERE/Supervisory Patent Examiner, Art Unit 2834