DETAILED ACTION
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 18 May 2026. In view of this communication, claims 1-20 are now pending in the application, with claims 12-14 being withdrawn from consideration.
Priority
Receipt is acknowledged of papers submitted under 35 U.S.C. 119(e), which papers have been placed of record in the file.
Election/Restrictions
Claim(s) 12-14 is/are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 18 May 2026.
Disclosure
The specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant's cooperation is requested in correcting any errors of which applicant may become aware in the specification.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL. — The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim(s) 8 and 16-17 is/are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for pre-AIA the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claims 8 and 16 recite a “pilot fit” between the housing and the sleeve. While a “pilot fit” is known in the art as generally comprising some form of projecting surface, often cylindrical, to ensure proper alignment of two components, no such surface is evident in the drawings of the present application. Further, since the written description includes no explanation of the structure, besides the term “pilot fit”, it is unclear what structure corresponds to the claimed interface.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION. — The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim(s) 8 and 16-17 is/are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention.
Claims 8 and 16 recite a “pilot fit” between the housing and the sleeve. This term is indefinite for the same reasons given above. Further, in the grounds of rejection below, since no corresponding structure has been clearly disclosed, this term has simply been interpreted as requiring that inner and outer surfaces of the housing and sleeve, respectively, be in contact with one another.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claim(s) 1-3, 5-10, and 15-18 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Vanhee et al. (US 2023/0093220 A1), hereinafter referred to as “Vanhee”.
Regarding claim 1, Vanhee discloses an electric machine [101] cooling system [102] (fig. 1-6; ¶ 0017), comprising:
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a sleeve [214] enclosing a stator [200] and a rotor [210] (fig. 2; ¶ 0030);
a housing [216] removably coupled to the sleeve [214] and circumferentially enclosing a portion of the sleeve [214] (fig. 2; ¶ 0030, 0035); and
a fluid inlet [120] extending through at least one of the sleeve [214] and the housing [216] and is in fluidic communication with a first end winding chamber [ewc1] that surrounds a stator end winding [203] (fig. 2; ¶ 0045);
wherein the first end winding chamber [ewc1] is included in a stator cooling assembly [112] (fig. 2; ¶ 0020-0021).
Regarding claim 2, Vanhee discloses the electric machine [101] cooling system [102] of claim 1, as stated above, wherein the sleeve [214] includes a section that forms a boundary of the first end winding chamber [ewc1] (fig. 2; the left-most portion of the sleeve extends axially beyond the stator and forms the outer radial surface of the first end winding chamber).
Regarding claim 3, Vanhee discloses the electric machine [101] cooling system [102] of claim 1, as stated above, wherein the stator cooling assembly [112] includes:
a second end winding chamber [ewc2] positioned on a second axial side of the electric machine [101] (fig. 2; ¶ 0020-0021); and
a cooling channel [230,232] axially extending through a stator core [202] and in fluidic communication with the first end winding chamber [ewc1] and the second end winding chamber [ewc2] (fig. 2; ¶ 0037-0038).
Regarding claim 5, Vanhee discloses the electric machine [101] cooling system [102] of claim 3, as stated above, further comprising a first end winding sealing component [217] forming at least a portion of a boundary of the first end winding chamber [ewc1] (fig. 2; ¶ 0033).
Regarding claim 6, Vanhee discloses the electric machine [101] cooling system [102] of claim 5, as stated above, further comprising a second end winding sealing component [218] forming at least a portion of a boundary of the second end winding chamber [ewc2] (fig. 2; ¶ 0033).
Regarding claim 7, Vanhee discloses the electric machine [101] cooling system [102] of claim 5, wherein the first end winding sealing component [217] is coupled with the sleeve [214] (fig. 2; ¶ 0033).
Regarding claim 8, Vanhee discloses the electric machine [101] cooling system [102] of claim 1, as stated above, wherein the housing [216] is pilot fit to the sleeve [214] (fig. 2; ¶ 0035; the surfaces are in “face sharing contact”).
Regarding claim 9, Vanhee discloses the electric machine [101] cooling system [102] of claim 1, as stated above, further comprising a seal [302,402] positioned at an interface between the housing [216] and the sleeve [214] adjacent to the fluid inlet [120] (fig. 3-4; ¶ 0046-0047).
Regarding claim 10, Vanhee discloses the electric machine [101] cooling system [102] of claim 1, as stated above, wherein a working fluid in the stator cooling assembly [112] is oil (¶ 0020-0021).
Regarding claim 15, Vanhee discloses a traction motor [101] immersion cooling system [102] (fig. 1-6; ¶ 0017), comprising:
a sleeve [214] enclosing a stator [200] and a rotor [210] (fig. 2; ¶ 0030);
a housing [216] removably coupled to the sleeve [214] and circumferentially enclosing a portion of the sleeve [214] (fig. 2; ¶ 0030, 0035); and
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a fluid inlet [120] extending through at least one of the sleeve [214] and the housing [216] and is in fluidic communication with a first end winding chamber [ewc1] that surrounds a stator end winding [203] (fig. 2; ¶ 0045);
wherein the first end winding chamber [ewc1] is included in a stator cooling assembly [112] (fig. 2; ¶ 0020-0021); and
wherein the sleeve [214] includes a flange [214f] and the housing [216] is coupled to the flange [214f] via an attachment device (fig. 2; ¶ 0033; the housing components are fixed “via bolts, screws, and/or other suitable attachment devices”).
Regarding claim 16, Vanhee discloses the traction motor [101] immersion cooling system [102] of claim 15, as stated above, wherein the housing [216] forms a pilot fit interface with the sleeve [214] (fig. 2; ¶ 0035; the surfaces are in “face sharing contact”).
Regarding claim 17, Vanhee discloses the traction motor [101] immersion cooling system [102] of claim 16, as stated above, wherein a diameter of the pilot fit interface is substantially constant along an axial length from the flange [214f] to an axial end (fig. 2; the surfaces are shown extending substantially straight in the axial direction).
Regarding claim 18, Vanhee discloses the traction motor [101] immersion cooling system [102] of claim 15, as stated above, wherein the stator cooling assembly [112] is pressurized (fig. 2; ¶ 0021; the system is pressurized by pump [116]) and includes:
the first end winding chamber [ewc1] positioned on a first axial side of the traction motor [101] and in direct fluidic communication with the fluid inlet [120] (fig. 2; ¶ 0045);
a second end winding chamber [ewc2] positioned on a second axial side of the traction motor [101] (fig. 2; ¶ 0020-0021); and
a cooling channel [230,232] axially extending through a stator core [202] (fig. 2; ¶ 0037-0038).
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claim(s) 4 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Vanhee in view of Lehmann (US 2023/0043424 A1), hereinafter referred to as “Lehmann”.
Regarding claim 4, Vanhee discloses the electric machine [101] cooling system [102] of claim 3, as stated above, further comprising a pump [116] (fig. 2; ¶ 0021).
Vanhee does not disclose a rotor shaft conduit in fluidic communication with the second end winding chamber [ewc2] and the pump [116].
Lehmann discloses an electric machine [1] cooling system [200] (fig. 5; ¶ 0158) comprising a rotor shaft [212] and end winding chambers (fig. 5; ¶ 0145-0148), further comprising a rotor shaft conduit [230] in fluidic communication with the second end winding chamber (fig. 5; ¶ 0146-0148, 0150).
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It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to form the back cover and shaft of Vanhee having fluid conduits as taught by Lehmann, in order to provide a uniform distribution of the cooling fluid within the electric machine (¶ 0055-0056 of Lehmann).
Regarding claim 20, Vanhee discloses the traction motor [101] immersion cooling system [102] of claim 18, as stated above, further comprising a back cover [217] (fig. 2; ¶ 0033).
Vanhee does not disclose the back cover [217] that forms a portion of a boundary of a conduit that directs fluid from the second end winding chamber to a rotor shaft conduit.
Lehmann discloses a traction motor [1] immersion cooling system [200] (fig. 5; ¶ 0158) comprising a rotor shaft [212] and end winding chambers (fig. 5; ¶ 0145-0148), further comprising a back cover [60] that forms a portion of a boundary of a conduit [208] that directs fluid from the second end winding chamber to a rotor shaft conduit [230] (fig. 5; ¶ 0145-0148, 0150).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to form the back cover and shaft of Vanhee having fluid conduits as taught by Lehmann, in order to provide a uniform distribution of the cooling fluid within the electric machine (¶ 0055-0056 of Lehmann).
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Vanhee in view of Chamberlin et al. (US 2014/0265659 A1), hereinafter referred to as “Chamberlin”.
Regarding claim 11, Vanhee discloses the electric machine [101] cooling system [102] of claim 1, as stated above. Vanhee does not disclose that the electric machine [101] is a multi-phase electric machine.
Chamberlin discloses an electric machine [1] (fig. 1-5; ¶ 0027), wherein the electric machine is a multi-phase electric machine (fig. 4a; ¶ 0027, 0044; the machine is a three-phase traction motor).
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It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to form the traction motor of Vanhee having multiple phases as taught by Chamberlin, in order to increase performance and efficiency by providing more power in a smaller space (¶ 0004, 0036 of Chamberlin).
Claim(s) 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 2022/0109350 A1), hereinafter referred to as “Kim”.
Regarding claim 19, Vanhee discloses the traction motor [101] immersion cooling system [102] of claim 18, as stated above. Vanhee does not disclose that the first end winding chamber [ewc1] includes a seal that is adjacent to an inner diameter of the stator.
Kim discloses a traction motor immersion cooling system [1] comprising a stator [80] with a first end winding chamber [300] (fig. 1; ¶ 0047), wherein the first end winding chamber [300] includes a seal [200a] that is adjacent to an inner diameter of the stator [80] (fig. 1; ¶ 0050-0051).
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It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to form the traction motor of Vanhee having seals on the inner sides of the end winding chambers as taught by Kim, in order to separate the cooling fluid of the rotor and the stator thereby increasing cooling efficiency of the stator core and the coils (¶ 0026-0027 of Kim).
Citation of Relevant Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant’s disclosure. Prior art:
Vanhee et al. (US 2023/0261536 A1) discloses a traction motor with a cooling system, comprising a sleeve within a housing, a fluid inlet, and a shaft conduit directing a cooling fluid over end windings of the stator.
Lang et al. (US 2022/0200373 A1) discloses a traction motor with a cooling system comprising a sleeve within a housing, and a fluid inlet directing a cooling fluid over end windings of the stator.
Brauer et al. (US 2017/0012500 A1) discloses a motor with a cooling system comprising a fluid inlet and a shaft conduit directing a cooling fluid over the end windings of the stator.
Iund et al. (US 2008/0024020 A1) discloses a motor with a cooling system, comprising a sleeve within a housing, a fluid inlet, and a shaft conduit directing a cooling fluid over end windings of the stator.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Michael Andrews whose telephone number is (571)270-7554. The examiner can normally be reached on Monday-Thursday, 8:30am-3:00pm.
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 an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/Michael Andrews/
Primary Examiner, Art Unit 2834
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