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 . Claims 1, 5-12 and 14-20 are pending.
Response to Arguments
Applicant's arguments filed 05/18/2026 have been fully considered but they are not persuasive.
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As seen in the screenshot above, Applicant’s main argument is that Engelhardt et al. (US 20220385127 A1) does not disclose any coolant flows through the slots. Examiner considers any continuous recess in the stator core in which a winding is disposed as a stator slot. In fig. 6, one can clearly see that the recess 30, that includes a cooling channel 24, is connected to the recess 20 to form a slot in the stator core. While Engelhardt refers to the recess 20 as slot, he explicitly states that the recesses 30 and 20 are connected (see para [0033]: “There is no sheet-metal material of the sheet-metal blanks 14, and thus of the laminated stator core 13, radially between the coolant flow channels 24 and the slots 20.”)
Furthermore, each of the other two cited prior art in the non-final Office action dated 02/18/2026 teach having a cooling channel within a stator slot, see for example fig. 2 in Diehl et al. (US 20210328472 A1), and figs. 13-14 in Pena et al (WO 2024046562 A1). This also means having a cooling channel within a stator slot is known and within the skills of those having ordinary skills in the art.
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 and 5-10 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Engelhardt et al. (US 20220385127 A1).
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Regarding claim 1, Engelhardt discloses an electric machine (fig. 1) defining a radial direction, a circumferential direction, and an axial direction, the electric machine comprising:
a stator core (core, annotated fig. 1) including a first end (first end, annotated fig. 1) and a second end (second end, annotated fig. 1) and defining a plurality of axial slots extending in the axial direction from the first end to the second end (para [0028]: “The sheet-metal blanks 14, and thus the laminated stator core 13, have a plurality of slots 20, which serve to accommodate stator windings 21.”);
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a seal member (seal, annotated fig. 6) extending through the plurality of axial slots in the axial direction from the first end of the stator core to the second end of the stator core (implied);
a plurality of windings (winding, annotated fig. 6) extending through the seal member in the axial direction and disposed in the plurality of axial slots (see annotated figs. 1 and 6);
a first outer casing (end cap-1, annotated fig. 1) disposed at the first end over the seal member, the first outer casing including a fluid port (inlet, annotated fig. 1);
a second outer casing (end cap-2, annotated fig. 1) disposed at the second end over the seal member, wherein the first outer casing, the second outer casing, and the seal member encapsulate the plurality of windings within the plurality of axial slots (see annotated fig. 1 wherein the coolant is limited to the stator and isolated from the rotor), and
a fluid supply in fluid communication with the fluid port of the first outer casing (see annotated fig. 1, supply 33 provides coolant to inlet port), the fluid supply including a coolant fluid (see para [0036], “coolant inflow 27”), wherein the coolant fluid is disposed through each of the plurality of axial slots (see annotated fig. 6; each coolant is within a slot formed in the stator core).
Regarding claim 5, Engelhardt discloses the electric machine of claim 1, wherein the first outer casing, the second outer casing, and the seal member form a fluidtight chamber encapsulating the plurality of windings (see annotated fig. 1, implied because the rotor is isolated- limiting the cooling fluid only to the stator).
Regarding claim 6, Engelhardt discloses the electric machine of claim 1, wherein the second outer casing includes a second fluid port (see outlet, annotated fig. 1).
Regarding claim 7, Engelhardt discloses the electric machine of claim 6, wherein the fluid port of the first outer casing is in fluid communication with the second fluid port of the second outer casing via the plurality of axial slots (implied, see the cooling circuit in fig. 1).
Regarding claim 8, Engelhardt discloses the electric machine of claim 1, wherein the seal member includes a plurality of axial seals that extend around the stator core in the circumferential direction (the slots extend in the stator core in axial direction and distributed in the circumferential direction) and a terminal seal (terminal seal, annotated fig. 1) disposed on the second end of the stator core.
Regarding claim 9, Engelhardt discloses the electric machine of claim 8, wherein each of the plurality of axial seals includes: a slot member (slot member, annotated fig. 6) extending through one of the plurality of axial slots; and a stop (stop, annotated fig. 6) extending in the circumferential direction across a width of the one of the plurality of axial slots.
Regarding claim 10, Engelhardt discloses the electric machine of claim 1, wherein the stator core further comprises an inner surface in the radial direction and the seal member is flush with the inner surface of the stator core (see sleeve 35 in fig. 4 described in para [0055]: “FIGS. 4 and 5 show a modification of the stator according to the invention, in which a sleeve 35, which prevents the coolant from getting into the region of the rotor 15, adjoins the laminated stator core 13 radially on the inside.”, and the seal member in annotated fig. 6).
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 (i.e., changing from AIA to pre-AIA ) 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.
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 11 is rejected under 35 U.S.C. 103 as being unpatentable over Engelhardt in view of Diehl et al. (US 20210328472 A1).
Regarding claim 11, Engelhardt discloses the electric machine of claim 1, wherein the stator core defines a plurality of channels (see two channel 24 in annotated fig. 6), but does not disclose: each channel disposed between two of the plurality of windings.
Diehl, with reference to annotated fig. 2, below, teaches a very similar electric machine wherein a seal (seal) is used to enclose the windings and a cooling channel (channel) within a stator core slot and the cooling channel is between two of the plurality of windings. Accordingly, having each channel disposed between two of the plurality of windings is an obvious option with predictable outcome when only two windings share a slot.
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For an electrical machine with two windings per slot, it would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention that each channel disposed between two of the plurality of windings. This would reduce the number of channels per slot while cooling the two windings equally.
Claim(s) 12, 14-20 are rejected under 35 U.S.C. 103 as being unpatentable over Engelhardt et al. (US 20220385127 A1) in view of Pena et al. (WO 2024046562 A1).
Regarding claim 12, Engelhardt, as already discussed regarding claim 1, discloses an electric machine defining a radial direction, a circumferential direction, and an axial direction, the electric machine comprising:
a stator core including a first end and a second end opposing the first end in the axial direction,
the stator core defining a plurality of slots extending in the axial direction from the first end to the second end and a plurality of channels extending in the axial direction from the first end to the second end;
a plurality of stops, each one of the plurality of stops disposed in one of the plurality of slots and extending in the circumferential direction across a width of the respective one of the plurality of slots and in the axial direction from the first end to the second end, and
a plurality of windings (winding, annotated fig. 6), each of the plurality of windings being disposed in one of the plurality of slots (see annotated fig. 6); and
a coolant fluid disposed through each of the plurality of slots (see annotated fig. 6; discussed regarding claim 1).
Engelhardt does not disclose: each one of the plurality of channels being disposed between two adjacent ones of the plurality of slots in the circumferential direction.
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Pena teaches (see annotated fig. 15, above) a similar electric machine wherein at least one internal cooling channels is used for cooling the teeth (teeth, annotated fig. 15) of the stator. While Engelhardt disclosed cooling channels for cooling the windings, clearly, additional channels can be used to cool the teeth of the stator when needed.
For cooling the stator teeth, it would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to modify the electric machine in such a way that: each one of the plurality of channels being disposed between two adjacent ones of the plurality of slots in the circumferential direction.
Regarding claim 14, Engelhardt as modified by Pena in claim 12 discloses the electric machine of claim 12, wherein each one of the plurality of stops is disposed inward in the radial direction of the respective one of the plurality of windings disposed in the one of the plurality of slots (see stop in annotated fig. 6).
Regarding claim 15, Engelhardt as modified by Pena in claim 12 discloses the electric machine of claim 14, wherein, in each one of the plurality of slots, the respective one of the plurality of stops disposed therein defines a stop channel with the respective one of the plurality of windings disposed therein (see stop in annotated fig. 6), the stop channel extending in the axial direction from the first end of the stator core to the second end of the stator core (implied- see the cooling channels in the axial direction in fig. 1).
Regarding claim 16, Engelhardt as modified by Pena in claim 12 discloses the electric machine of claim 12, further comprising an outer casing disposed at the first end of the stator core and the second end of the stator core, the outer casing encapsulating the plurality of windings within the plurality of slots (discussed regarding claim 1).
Regarding claim 17, Engelhardt as modified by Pena in claim 12 discloses the electric machine of claim 12, wherein the stator core defines an inner surface in the radial direction, and the plurality of stops are flush with the inner surface of the stator core (discussed regarding claim 10).
Regarding claim 18, Engelhardt as modified by Pena in claim 12, discloses the electric machine of claim 12, but does not disclose: further comprising an extension disposed on an exterior surface of the stator core in the radial direction, the extension defining an outer channel with the exterior surface of the stator core.
Pena also teaches cooling the stator core via a cooling jacket that includes: an extension (housing) disposed on an exterior surface of the stator core in the radial direction, the extension defining an outer channel (external cooling channel) with the exterior surface of the stator core. The cooling jacket will remove heat from the bulk of stator core.
For removing heat from the outer surface of the stator core, it would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to modify the electric machine in such a way that: the electric machine of claim 12, further comprising an extension disposed on an exterior surface of the stator core in the radial direction, the extension defining an outer channel with the exterior surface of the stator core.
Regarding claim 19, Engelhardt as modified by Pena in claim 12 discloses the electric machine of claim 12, further comprising a fluid port in fluid communication with the plurality of channels (discussed regarding claim 1).
Regarding claim 20, Engelhardt as modified by Pena in claim 12 discloses the electric machine of claim 12, wherein the plurality of slots are arranged into a plurality of pairs of slots, each pair of slots including a first slot and a second slot, and wherein each of the plurality of channels is disposed between the respective first slot and the respective second slot of each of the plurality of pairs of slots (see internal cooling channels in annotated fig. 15, Pena).
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.
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/MASOUD VAZIRI/Examiner, Art Unit 2834
/OLUSEYE IWARERE/Supervisory Patent Examiner, Art Unit 2834
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