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 .
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.
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.
Claims 1, 2, 4, 5 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over T Qu et al. (Qu, Timing & Song, Peng & Yu, Xiaoyu & Gu, Chen & Li, Longnian & Li, Xiaohang & Wang, Dewen & Hu, Boping & Chen, Duxing & Zeng, Pan & Han, Zhenghe. (2014). Development and testing of a 2.5 kW synchronous generator with a high temperature superconducting stator and permanent magnet rotor. Superconductor Science and Technology. 27. 044026. 10.1088/0953-2048/27/4/044026.) in light of Liang et al. (US 20180191228 A1).
With regard to claim 1, T Qu et al. teaches “A superconducting motor stator comprising (T Qu et al. teaches a generator stator: however, it would have been obvious to a person of ordinary skill in the art that a generator can be used as a motor stator by providing electricity through the windings to cause the rotor to spin):
a cooling element (T Qu et al. Fig. 1 at d, f), referred to as a cryogenic cooler, configured to circulate a cryogenic fluid therein (T Qu et al., Figs. 1-2 at d, f: The dewar along with the liquid nitrogen input and output pipes serve as the cooling element, and are designed to circulate liquid nitrogen and (as it warms) gaseous nitrogen through the system), and
a plurality of superconducting windings each forming an electromagnetic pole of said stator (T Qu et al., Fig. 1 at a) ,
wherein said cryogenic cooler has a ring shape comprising an inner wall along an inside diameter of said ring shape (T Qu et al., Fig. 2, see : see also, Page 3: “stainless steel Dewar, which is a double-wall stainless steel tube),
wherein one or more . . . magnetic structures (T Qu et al., Figs. 1-2 at c: “stator iron”) are arranged in contact with said inner wall (T Qu et al., Figs 1-2), . . . and,
wherein each of said superconducting windings (T Qu et al., Figs. 1-2 at a) is arranged on a hybrid magnetic structure, on an opposite side of said hybrid magnetic structure with respect to said inner wall (T Qu et al., Fig. 2b: Coils are arranged opposite the dewar from the iron core), such that the one or more hybrid magnetic structures carry out a transfer of heat between said superconducting windings and said inner wall (T Qu et al., Fig. 2; Pgs. 3-4: “To realize the conduction cooling, the stator iron and the HTS coils were pressure mounted into the stainless steel Dewar . . . The inner wall of the Dewar worked not only as the cold source, but also as the generator shell”).”
T Qu et al. does not explicitly teach that the stator iron is a “hybrid” magnetic structure wherein “the one or more hybrid magnetic structures comprising a stack of first elements made from a first, magnetically conducting, material and of second elements made of a second, thermally conducting, material, the stack being such that ends of each of said first and second elements are respectively in contact with said inner wall and with one of said superconducting windings.”
Liang et al. (US 20180191228 A1) teaches a “hybrid magnetic structure (Liang et al., Figs. 2-5 at 100)” wherein “the one or more hybrid magnetic structures comprising a stack of first elements (Liang et al., Figs. 2-5 at 110) made from a first, magnetically conducting, material (Liang et al., Paragraph [0014]) and of second elements (Liang et al., Figs. 2-5 at 120) made of a second, thermally conducting, material (Liang et al., Paragraph [0021], Table A: “Thermally conductive electrically insulating material that be included in one or more electrical insulating layer 120”), the stack being such that ends of each of said first and second elements are respectively in contact with said inner wall and with one of said superconducting windings (Liang et al., Figs. 2-5: Liang et al. shows and teaches the layers going from one end of the apparatus (top) to the other (bottom), in order to improve the thermal conductivity of the apparatus and more fully prevent eddy currents)).” Further, Liang et al. teaches the superconducting motor stator according to claim 1, as described above. Liang et al. further teaches “wherein said stack further comprises at least one insert element arranged between one of said first elements and one of said second elements, or between two of said first elements, or between two of said second elements (Liang et al., Figs. 2-3, at 115; Paragraph [0030]).”
It would have been obvious for a person of skill in the art to adopt the teachings of Liang et al. to those of T Qu et al. in order to improve the thermal conductivity of the stator iron to better cool the superconducting windings. T Qu et al. demonstrates a stator made by layering magnetic material (silicon steel sheets) (T Qu et al., Page 4). T Qu et al. also teaches that the silicon steel layers are not ideal for this application (T Qu et al. Page 7). Liang et al. teaches a magnetic structure that includes both magnetic materials and an electrically insulating layer between the magnetic materials made of a thermally conductive material (Liang et al., Paragraph [0015]), which improves the thermal conductivity of the magnetic structure (Liang et al., Paragraphs [0020]-[0021]). A person of skill in the art seeking to improve the cooling of the superconducting coils of T Qu et al. would have been motivated to utilize the teachings of Liang et al. to modify the magnetic structure (the stator iron) in order to improve the thermal conductivity thereof. This would result in a magnetic structure having layers of magnetic material and layers of electrically insulating, thermally conductive material going from the inner end of the stator iron (in contact with the superconducting coils) to the outer end of the stator iron (in contact with the inner wall of the Dewar).
With regard to claim 2, the combination of T Qu et al. and Liang et al. teaches the superconducting motor stator according to claim 1, as described above. Liang et al. further teaches “wherein the first material comprises iron (Liang et al., Paragraph [0014]) and wherein the second material comprises sapphire, copper, diamond or aluminum (Liang et al., Paragraph [0020]).”
With regard to claim 4, the combination of T Qu et al. and Liang et al. teaches the superconducting motor stator according to claim 1, as described above. Liang et al. further teaches “wherein the stack of the first elements and the second elements is regular (Liang et al., Figs. 2, 4, 5).”
With regard to claim 5, the combination of T Qu et al. and Liang et al. teaches the superconducting motor stator according to claim 1, as described above. Liang et al. further teaches “wherein the stack of the first elements and the second elements is irregular (Liang et al., Figs. 1, 3: Each showing two second elements (120) separated by a third elements (130, 160), with no first elements between them).”
With regard to claim 7, the combination of T Qu et al. and Liang et al. teaches “A superconducting motor comprising: the superconducting motor stator according to claim 1.” T Qu et al. teaches a superconducting generator comprising rotor and stator. It would have been obvious to a person of ordinary skill in the art to adapt the generator for use in a motor. T Qu et al. mentions several times a “generator/motor,” and treats the basic concepts of each as interchangeable, as is customary in the art. Therefore, a person of ordinary skill in the art would find it obvious to use the generator of T Qu et al. and Liang et al. as a motor.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over the combination of T Qu et al. and Liang et al. as applied to claim 1 above, and further in view of Velderman et al. (US 20190273421 A1).
The combination of T Qu et al. and Liang et al. teaches the superconducting motor stator of claim 1 as described above.
The combination of T Qu et al. and Liang et al. does not explicitly teach “wherein the stack comprises between 70% and 80% of first elements and between 20% and 30% of the second elements.”
Velderman et al. teaches “wherein the stack comprises between 70% and 80% of first elements and between 20% and 30% of the second elements (Velderman et al., Paragraph [0201]).”
While the combination of T Qu et al. and Liang et al. does not explicitly teach what percentage of the magnetic apparatus should be each element, in Liang et al., it does teach that the thermally conductive layer (Liang et al., Figs. 1-5, 120) is thinner than the magnetic layer (Liang et al., Figs. 1-5, 110). It would have been within the skill of a person of ordinary skill in the art to modify the thickness of the layers to achieve an apparatus with an appropriate thermal conductivity. Velderman et al. teaches that a thermally conductive layer may be between 2.8% and 28% of the thickness of the magnetic layer. A person of ordinary skill in the art would be able to optimize the thickness of the thermally conductive layer in order to balance the magnetic properties with the needed thermal conductivity for a given use and come up with a layer thickness similar to that of Velderman et al. and that shown in the figures of Liang et al., having the second elements be approximately 20%-30% of the stack.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over the combination of T Qu et al. and Liang et al. as applied to claim 1 above, and further in view of Xiao et al. (US 20220302816 A1).
The combination of T Qu et al. and Liang et al. teaches the superconducting motor of claim 7, as described above. The combination of T Qu et al. and Liang et al. does not explicitly teach “an aircraft comprising at least one superconducting motor according to claim 7.”
Xiao et al. “teaches an aircraft comprising at least one superconducting motor (Xiao et al., Paragraph [0049]).”
It would have been obvious to a person of ordinary skill in the art at the time of filing to adapt the superconducting motor taught by T Qu et al. and Liang et al. to use in an aircraft as taught by Xiao et al., in order to provide an electrical motor for powering an aircraft.
Response to Arguments
Applicant's arguments filed 11/17/2025 have been fully considered but they are not persuasive.
Applicant alleges that “the materials mentioned for the buffer layer 115 are thermally conducting material, and thus a buffer layer 115 of Liang would correspond to a second element of the stack according to the invention. Hence, the buffer layer 115 of Liang would not be considered by one or ordinary skill in the art as an insert element according to the invention.” The examiner respectfully disagrees.
Liang explicitly teaches distinct layers 110, 115 and 120, each formed of distinct materials. The term “insert element” is not defined by claim 1 as having any particular property or material composition, rather, that it is an element that is arranged between first elements and/or second elements in the hybrid magnetic structure stack. Buffer layer 115 of Liang is clearly shown to be located between a first element (110) and a second element (120) in figures 2 and 3, i.e. inserted between. Moreover, buffer layer 115 is a distinct material composition form elements 110 and 120. Further, the fact that buffer layer 115 may be thermally conductive does not impart a requirement that it be considered a component of the second element since they are structurally and materially distinct layers. Accordingly, buffer layer 115 reads on the claimed “insert element” as recited in claim 1 and applicants remarks have not been found persuasive.
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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/CHRISTOPHER M KOEHLER/Supervisory Patent Examiner, Art Unit 2834