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 19 December 2025. In view of this communication and the amendment concurrently filed: claims 1-12 and 14 were previously pending; claim 12 was cancelled and claims 15-17 were added by the amendment; and thus, claims 1-11 and 14-17 are now pending in the application, with claim 5 being withdrawn from consideration.
Response to Arguments
The Applicant’s arguments, filed 19 December 2025, have been fully considered but are not persuasive.
The Applicant’s first argument (pages 6-9 of the Remarks) alleges that Gugel, in view of Saint-Michel, does not disclose the newly added limitation of claim 1 reciting “a contained space” on either end of the stator. While it is acknowledged that neither Gugel nor Saint-Michel discloses said spaces, the Sakurai reference, previously applied in the grounds of rejection of claims 8-10, does disclose this feature. As such, new grounds of rejection have been applied in view of Sakurai.
The Applicant’s second argument (pages 9-10 of the Remarks) alleges that Gugel does not disclose coolant being discharged axially from the stator lamination package as now recited in claim 1, previously in claim 12. However, the arguments repeatedly misconstrue the disclosure of Gugel, conflating the coolant leaving the winding heads radially with the coolant leaving the stator laminations (axially). The stator slots are open in the axial direction and the winding heads extend axially from the stator slots. Coolant flows from the stator slots, axially, to the winding heads (see fig. 1-2). Thus, the coolant is discharged from the stator slots/laminations toward the winding heads in the axial direction. The fact that the coolant then leaves the winding heads radially, after leaving the stator axially, does not negate the fact that the coolant leaves the stator lamination package in the axial direction thereby meeting the claim limitation. Thus, this argument is unpersuasive and the previous grounds of rejection are maintained.
The Applicant’s third argument (pages 11-12 of the Remarks) alleges that modifying Gugel in view of Saint-Michel would render Gugel unsatisfactory for its intended purpose. The argument alleges that said purpose is to expel cooling fluid through the slot openings. While this is one means of expelling the cooling fluid disclosed by Gugel, it is not the only means (¶ 0032 of Gugel; cooling fluid exits the slots via the radial openings toward the air gap or the axial openings at the winding heads). Thus, closing the slots would not prevent the fluid from exiting, even if this were the "intended purpose" of the device, though no evidence of this premise has been shown. Thus, this argument is also unpersuasive.
The Applicant’s fourth argument (pages 12-13 of the Remarks) alleges that the cited motivation for modifying Gugel in view of Saint-Michel only applies to closing the slots, not closing the slots "using the laminations" as discussed in the grounds of rejection. However, the improved structural rigidity discussed in said grounds is provided by closing the slots using the solid material of the stator rather than a separate wedge. And, the improved cogging torque is provided by the inner surface of the stator being uniform, also a feature of the closed slots rather than the open slots closed by a wedge. Thus, this argument is also unpersuasive and the previous grounds of rejection are maintained.
While the argument further alleges that the above response to the fourth argument is not supported by the disclosure of either reference, this allegation is simply false. Saint-Michel explicitly discloses the slots being closed by the laminations (fig. 4-5; ¶ 0162; “bridges of material 27”) and that doing so reduces both vibrations and cogging torque (¶ 0017). Further, these allegations themselves have no support, as no evidence is provided in regard to either of them. Thus, this argument is also unpersuasive and the previous grounds of rejection are maintained.
The Applicant’s fifth argument (page 13 of the Remarks) alleges that the new claims are allowable by virtue of their dependency on claim 1. This is unpersuasive for the reasons given above and for those presented in the new grounds of rejection below.
Priority
Receipt is acknowledged of papers submitted under 35 U.S.C. 119(a)-(d) or (f), 365(a) or (b), or 386(a), which papers have been placed of record in the file.
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) 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.
Claim 16 recites the limitation “each second contained space is sealed radially inwardly by the respective contained space”. However, the application, as originally filed, discloses the second contained space [38] being sealed by sealing components [37,40] (fig. 8-11; ¶ 0075 of the specification; “sealing body 37 is sealed via a further sealing element 40”), not by the contained space [39]. Thus, this recitation of claim 16 constitutes new matter. Further, it is unclear how one open space can be sealed by another open space, as open spaces inherently allow matter to pass through them. Thus, this limitation also renders the claim indefinite.
Claim 17 is rejected due to its dependency on claim 16.
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) 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.
Claim 16 recites the limitation “each second contained space is sealed radially inwardly by the respective contained space”. It is unclear how one open space can be sealed by another open space, as open spaces inherently allow matter to pass through them. Thus, this limitation renders the claim indefinite.
Claim 17 is rejected due to its dependency on claim 16.
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.
Claim(s) 1-4, 6-11, and 14-15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Gugel et al. (US 2016/0006302 A1), hereinafter referred to as “Gugel”, in view of Saint-Michel et al. (US 2021/0203197 A1), hereinafter referred to as “Saint”, Sakurai et al. (US 2016/0156251 A1), hereinafter referred to as “Sakurai”, and Mantere (US 2010/0237727 A1), hereinafter referred to as “Mantere”.
Regarding claim 1, Gugel discloses a stator [12] of an electric machine [10] (fig. 1-2; ¶ 0020), comprising:
a stator lamination package [14] comprising a plurality of stator laminations [16,18,20] (fig. 1; ¶ 0020),
wherein the stator laminations [16,18,20] comprise radially inward recesses [24] that define portions of axially extending stator grooves [24] (fig. 2; ¶ 0021), and
wherein stator windings [28] are arranged in the stator grooves [24], directly around which windings [28] a coolant can flow within the stator grooves [24] (fig. 2; ¶ 0021-0022);
a coolant guide [16,18,20] arranged between the stator laminations [16,18,20] of the stator lamination package [14] (fig. 1; ¶ 0024; the arrangement of the three centrally located laminations creates the radial recess [44] to guide coolant from radially outward recesses [42] to the stator grooves [24]); and
wherein the coolant guide [16,18,20] comprises first lamination blanks [16,20] axially bordering the coolant guide [16,18,20] on opposite sides thereof (fig. 1; ¶ 0024),
wherein the coolant guide [16,18,20] comprises second lamination blanks [18] arranged between the first lamination blanks [16,20] (fig. 1; ¶ 0024),
wherein the first lamination blanks [16,20] and the second lamination blanks [18] as well as the stator laminations [16,18,20] radially comprise inward recesses [24] for defining the stator grooves [24] and for receiving the stator windings [28] (fig. 2; ¶ 0021-0022),
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wherein only the second lamination blanks [18] additionally comprise radial coolant channels [44] extending radially outward from the stator grooves [24] and configured to guide the coolant radially inward towards the stator grooves [24] or radially outward from the stator grooves [24] (fig. 1-2; ¶ 0024-0025),
wherein the radially inward recesses [24] of the stator laminations [16,18,20] and the lamination blanks [18,18,20] of the coolant guide [16,18,20] and thus the stator grooves [24] are closed in a radially inward direction (fig. 2; ¶ 0029; the stator grooves are closed on their radially inner side by “cover 68”), and
wherein axially adjacent stator laminations [16,18,20] and lamination blanks [16,18,20] of the stator lamination package [14] and the coolant guide [16,18,20] are glued together in a laminar manner (¶ 0030-0031; the stator laminations can be either loosely arranged or tightly sealed together using a “lacquer or something similar”).
Gugel does not disclose that the stator grooves are closed in a radially inward direction by the stator laminations and the lamination blanks.
Saint discloses a stator [2] comprising stator laminations/blanks having radially inward recesses [21] defining stator grooves [21] that are closed in a radially inward direction by the stator laminations/blanks (fig. 4-5; ¶ 0162-0164).
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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 close the stator slots of Gugel using the laminations as taught by Saint, rather than separate slot closers, in order to “reinforce the stator mechanically and reduce vibrations because a minimized “cogging torque” effect is obtained” (¶ 0017 of Saint).
Gugel, in view of Saint, does not disclose a contained space bordering the axially extending stator grooves [24] on each axial end of the stator lamination package [14], wherein each contained space is configured to exchange coolant with the axially extending stator grooves [24], and wherein each contained space is configured to be sealed from a rotor [34].
Sakurai discloses an electric machine [8] comprising a rotor [4] and stator [2] comprising laminations [14] (fig. 1-3; ¶ 0046-0048), further comprising a contained space [cs] bordering axially extending stator grooves [g] on each axial end of the stator lamination package [14], wherein each contained space [cs] is configured to exchange coolant with the axially extending stator grooves [g], and wherein each contained space [cs] is configured to be sealed from a rotor [4] (fig. 1-3; ¶ 0050-0052; the spaces are sealed by sleeve [16] and arrows, fig. 2, show the coolant flow through the stator).
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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 implement the electric machine of Gugel having contained spaces sealed by a sealing body as taught by Sakurai, in order to provide separate cooling of the rotor and the stator thereby allowing for reduced amounts of drag on the rotor by cooling fluid (¶ 0055, 0059 of Sakurai).
Gugel further discloses that the stator lamination package [14] is configured to receive coolant radially inward via the radial coolant channels [44] extending radially outward from the stator grooves [24] (fig. 1-2; ¶ 0024-0025), and
wherein the stator lamination package [14] is configured to discharge coolant axially outward on both axial sides of the stator lamination package [14] (fig. 1; ¶ 032; coolant exits the stator at the “winding heads 30”).
Gugel, in view of Saint and Sakurai, does not disclose that the stator lamination package [14] is configured to receive coolant axially inward on both axial sides of the stator lamination package [14] (fig. 1; inlets [56] are provided only on the left axial side of the stator lamination package).
Mantere discloses a stator [5] comprising a stator lamination package [4] (fig. 3; ¶ 0022-0024), wherein the stator lamination package [4] is configured to receive coolant axially inward on both axial sides of the stator lamination package [4] (fig. 3; ¶ 0025; coolant flows [6a] and [6b] flow into both axial ends of the stator through axial cooling channels [7a] and [7b]).
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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 implement the stator lamination package of Gugel having coolant inlets on both axial sides as taught by Mantere, in order to achieve even cooling over the entire axial length of the stator (¶ 0025 of Mantere).
Regarding claim 2, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator according to claim 1, as stated above, wherein at least the stator laminations [16,18,20] of the stator lamination package [14] and the first lamination blanks [16,20] of the coolant guide [16,18,20] comprise radially outward recesses [42], at least portions of which border axial coolant channels [50] for guiding the coolant (fig. 1-2; ¶ 0024, 0026-0027).
Regarding claim 3, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator according to claim 1, as stated above, wherein the first lamination blanks [16,20] of the coolant guide [16,18,20] axially cover the radial coolant channels [44] of the second lamination blanks [18] of the coolant guide [16,18,20] (fig. 1-2; ¶ 0024-0025).
Regarding claim 4, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator [12] according to claim 2, as stated above, wherein the second lamination blanks [18] of the coolant guide [16,20] also comprise radially outward recesses [42], which together border the axial coolant channels [50], wherein the radial coolant channels [44] of the second lamination blanks [18] extend between the stator grooves [24] and the axial coolant channels [50] (fig. 1-2; ¶ 0024, 0026-0027).
Regarding claim 6, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator [12] according to claim 1, as stated above, wherein at least the first lamination blanks [16,20] of the coolant guide [16,18,20] and the stator laminations [16,18,20] comprise radially outward cavities [42] (fig. 1-2; ¶ 0024, 0026-0027), which are designed to provide radial deformability of the stator lamination package (this function is not disclosed as requiring any additional structure beyond that already recited, and met by “conduit 42” of Gugel).
Regarding claim 7, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator [12] according to claim 1, as stated above, wherein the stator laminations [16,18,20], the first lamination blanks [16,20], and the second lamination blanks [18] are made of an identical material (¶ 0020; the entire lamination package, 14, is made from “a highly permeable iron material”).
Regarding claim 8, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator [12] according to claim 1, as stated above, wherein Sakurai further discloses a sealing body [16], which adjoins the stator laminations [14] and the lamination blanks [31] in the radially inward direction, and which projects in an axial direction opposite the stator lamination package [14] (fig. 1-3; ¶ 0051-0052).
Regarding claim 9, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator [12] according to claim 8, as stated above, wherein Sakurai further discloses that the sealing body [16] is designed as a self-stable gap tube [16], which adjoins the stator laminations and the first and second lamination blanks [31] in the radially inward direction without being connected to the stator lamination package (fig. 1-3; ¶ 0051-0052; the sleeve “adjoins” the laminations via “an interference or friction fit” without any solid connection thereto).
Regarding claim 10, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator [12] according to claim 9, as stated above, wherein the coolant guide [16,18,20] is arranged, in the axial direction, in a center of the stator lamination package [14] (fig. 1).
Regarding claim 11, Gugel, in view of Saint, Sakurai, and Mantere, discloses an electric machine [10] comprising a stator [12] according to claim 1, as stated above, and a rotor [34] (fig. 1; ¶ 0022).
Regarding claim 14, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator [12] according to claim 1, as stated above, wherein Gugel discloses that each of the stator laminations [16,18,20], and the first lamination blanks [16,20] comprise a respective monolithic construction (fig. 1-2); and
Saint further discloses that each lamination radially surrounds the stator grooves [21] to enclose the stator grooves [21] (fig. 4-5; ¶ 0162-0164).
Regarding claim 15, Gugel, in view of Saint, Sakurai, and Mantere, discloses the stator [12] according to claim 8, as stated above, wherein Sakurai further discloses that the sealing body [16] further adjoins the contained space [cs] in the radially inward direction and is configured to be arranged between the contained space [cs] and the rotor [4] (fig. 1-3; ¶ 0050-0052).
Allowable Subject Matter
The following is a statement of reasons for the indication of allowable subject matter:
Regarding claim 16, and all claims dependent thereon, the prior art does not disclose, inter alia, the stator according to claim 1, wherein each contained space borders a radially outward second contained space on each axial end of the stator lamination package, wherein each second contained space is configured to exchange coolant with radially outward stator grooves extending through the stator lamination package, and wherein each second contained space is sealed radially inwardly by the respective contained space.
While the prior art discloses contained spaces on the axial ends of stators, and said spaces are sometimes divided into multiple contained spaces, it does not disclose the particular arrangement recited above where subsequent spaces are sealed by preceding spaces (though this arrangement is, as stated in the grounds of rejection under 35 U.S.C. 112, unclear). However, at least in combination with the other recited features, the arrangement disclosed in figures 8-11 of the application, where the second contained space is sealed by “sealing body 37 is sealed via a further sealing element 40” rather than another contained space, is neither anticipated nor rendered obvious by the prior art.
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.”
Citation of Relevant Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant’s disclosure. Prior art:
Teringl et al. (US 2023/0243339 A1) discloses a stator having axial cooling channels through the slots and a radial cooling channel at its axial center, wherein coolant enters the stator from both axial ends.
Knoblauch et al. (US 2022/0052576 A1) discloses an electric machine having a rotor and a stator, wherein the stator space is separated from the rotor space by a cylindrical sleeve.
Bradfield (US 2020/0227977 A1) discloses a stator having axial cooling channels, wherein coolant enters the stator near both axial ends.
Saari et al. (US 2016/0190878 A1) discloses a stator comprising axial cooling channels through its annular yoke and a radial cooling channel at its axial center.
Pfannschmidt et al. (US 2007/0024129 A1) discloses a stator comprising axial cooling channels through its annular yoke and a radial cooling channel at its axial center.
Conclusion
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/Michael Andrews/
Primary Examiner, Art Unit 2834