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 in response to papers filed on 1/9/2026. Amendments made to the claims and the Applicant's remarks have been entered and considered.
Claims 1, 3, 4 have been amended. Claims 2, 7, 11-13 are cancelled.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 1/9/2026 has been entered.
Response to Arguments
Applicant's arguments filed 1/9/2026 have been fully considered but they are not persuasive.
The Applicant argued that the Office states that the heat exchanger 10 of Steinz comprises two heat exchangers, not one. This is an unreasonably broad interpretation of the term "heat exchanger."
This argument is not persuasive because, firstly, Merriam-Webster defines a heat exchanger as a device (such as an automobile radiator) for transferring heat from one fluid to another without allowing them to mix. An automobile radiator transfers heat from a liquid to ambient air. Steinz shows (FIG. 1):
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the described and illustrated heat exchanger 10 is divided into two separate first and second heat exchangers 10C and 10B. The first heat exchanger 10C carries the first cooling medium 8 and the second heat exchanger 10B carries the second cooling medium 9 which do not mix. Steinz describes the second cooling medium 9 as transmission oil having a higher viscosity (para [0036],[0037]; second cooling medium 9 has higher viscosity para [0031]). One of ordinary skill in the art would understand that the motor vehicle disclosed by Steinz is not operated in a vacuum but rather outdoors where the electric machine and the heat exchangers 10B, 10C are exposed to ambient air being a third fluid to which heat is transferred from the first cooling medium 8 through the first heat exchanger 10C and from the second cooling medium 9 through the second heat exchanger 10B. One of ordinary skill in the art would understand that the electric machine would overheat without this heat transfer to ambient air. The Applicant’s argument is therefore not persuasive.
The Applicant also argued that Steinz does not show a third cooling circuit which cools two separate heat exchangers.
This argument is moot because newly applied Bessho (JP2021024447 A) shows a third cooling circuit.
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.
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) 1, 3-6, 8, 10, 14 are rejected under 35 U.S.C. 103 as being unpatentable over Steinz et al. (US 2021/0006132 A1, hereinafter Steinz) in view of Krueger (DE 102015109690 A1) and Bessho (JP2021024447 A).
As to claim 1, Steinz shows (FIG. 1):
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A drive unit for an electric vehicle, comprising:
an electric motor 2 for propulsion;
a cooling system,
wherein the electric motor 2 comprises a stator assembly 4 and a rotor assembly 3,
wherein the stator assembly 4 comprises a stator housing (FIG. 1), a stator core 11 having grooves, and a winding assembly 12,
wherein the winding assembly 12 extends through the grooves,
wherein the stator housing comprises a stator housing inlet 14 and a stator housing outlet 15,
wherein the grooves are fluidically connected to the stator housing inlet 14 and the stator housing outlet 15,
wherein the cooling system comprises a first cooling circuit 6, which is connected to the stator housing inlet 14 and the stator housing outlet 15 so as to enable a direct cooling of the winding assembly 12 ;
a second cooling circuit 7;
a pumping apparatus,
wherein the pumping apparatus comprises a first pump and a second pump 23,
wherein the first pump is configured to convey a first coolant 8 in the first cooling circuit 6,
wherein the second pump 23 is configured to convey a second coolant 9 in the second cooling circuit 7, and
wherein the first coolant 8 and the second coolant 9 are different;
wherein the first cooling circuit comprises a first heat exchanger 10B and the second cooling circuit comprises a second heat exchanger 10C (electric vehicle para[0002]; electric machine 2 is implied to be a motor because it’s in a motor vehicle; para[0033]; windings in grooves, cooling windings para[0037]; it is implied that the first cooling medium is forced by a first pump; second cooling medium 9 has higher viscosity than the first cooling medium 8 para[0031]).
Steinz does not show:
the first cooling circuit comprises an expansion tank assembly, the expansion tank assembly comprising an expansion tank, at least one expansion tank inlet, one expansion tank outlet, and a pressure equalization assembly;
the expansion tank is connected to the first cooling circuit via the at least one expansion tank inlet and the expansion tank outlet;
the pressure equalization assembly is configured to enable, at least temporarily, a fluidic connection between the expansion tank and an ambient environment of the drive unit, in order to at least partially cause a pressure equalization between the expansion tank and the ambient environment;
the pressure equalization assembly comprises a first valve configured to transition from a non-conductive state into a conductive state when a pressure in the ambient environment is greater than a pressure in the expansion tank by at least a specified first amount in order to at least partially cause a pressure equalization in case of a negative pressure in the expansion tank, wherein the specified first amount is not equal to zero;
a third cooling circuit, and
wherein the third cooling circuit is configured to cool the first heat exchanger and the second heat exchanger.
As to the first four bullets Krueger shows (FIG. 2):
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the first cooling circuit 25 comprises an expansion tank assembly, the expansion tank assembly comprising an expansion tank 8, at least one expansion tank inlet 8A, one expansion tank outlet 8B, and a pressure equalization assembly 11;
the expansion tank 8 is connected to the first cooling circuit 25 via the at least one expansion tank inlet 8A and the expansion tank outlet 8B; and
the pressure equalization assembly 11 is configured to enable, at least temporarily, a fluidic connection between the expansion tank 8 and an ambient environment of the drive unit 3, in order to at least partially cause a pressure equalization between the expansion tank 8 and the ambient environment
the pressure equalization assembly comprises a first valve 11B configured to transition from a non-conductive state into a conductive state when a pressure in the ambient environment is greater than a pressure in the expansion tank 8 by at least a specified first amount in order to at least partially cause a pressure equalization in case of a negative pressure in the expansion tank 8, wherein the specified first amount is not equal to zero (vent valve 11 has spring 15 closure that opens in the range of higher 1-1.5 bar pressure in the atmosphere than in the expansion tank 8 and is closed with less of a pressure difference see FIG. 2 above and FIG. 3, 5 and para[0035],[0037],[0039],[0042]).
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 cooling circuit 6 of Steinz to have
the first cooling circuit 6 comprises an expansion tank assembly, the expansion tank assembly comprising an expansion tank 8, at least one expansion tank inlet 8A, one expansion tank outlet 8B, and a pressure equalization assembly 11;
the expansion tank 8 is connected to the first cooling circuit 6 via the at least one expansion tank inlet 8A and the expansion tank outlet 8B;
the pressure equalization assembly 11 is configured to enable, at least temporarily, a fluidic connection between the expansion tank 8 and an ambient environment of the drive unit, in order to at least partially cause a pressure equalization between the expansion tank 8 and the ambient environment; and
the pressure equalization assembly comprises a first valve 11B configured to transition from a non-conductive state into a conductive state when a pressure in the ambient environment is greater than a pressure in the expansion tank 8 by at least a specified first amount in order to at least partially cause a pressure equalization in case of a negative pressure in the expansion tank 8, wherein the specified first amount is not equal to zero
as taught by Krueger, for the advantageous benefit of equalizing the pressure between the first cooling circuit 6 and the outside as taught by Krueger (outside meaning ambient para[0015],[0037]).
As to the fifth and sixth bullets, Bessho shows (FIG. 1)
a third cooling circuit 81, and
wherein the third cooling circuit 81 is configured to cool the first heat exchanger H1 and the second heat exchanger H3 (heat transferred from 12 and 13 to 81 para [0019],[0022]).
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 drive unit of Steinz in view of Krueger to have:
a third cooling circuit 81, and
wherein the third cooling circuit 81 is configured to cool the first heat exchanger 10B and the second heat exchanger 10C
as taught by Bessho, for the advantageous benefit of stably cooling the electric machine motor as taught by Bessho (para[0007]).
As to claim 3/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1, and Steinz further shows wherein the first coolant is a dielectric coolant (oil para[0030]).
As to claim 4/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1 except for the pressure equalization assembly comprises a first filter apparatus, wherein the first filter apparatus is configured to reduce or prevent a discharge of the coolant into the ambient environment.
Krueger shows the pressure equalization assembly comprises a first filter apparatus, wherein the first filter apparatus is configured to reduce or prevent a discharge of the coolant into the ambient environment (membrane in vent valve 11 blocks the passage of coolant para[0037]).
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 cooling circuit 6 of Steinz in view of Krueger and Bessho to have the pressure equalization assembly comprises a first filter apparatus, wherein the first filter apparatus is configured to reduce or prevent a discharge of the coolant into the ambient environment as taught by Krueger, for the advantageous benefit of blocking the passage of coolant to the outside as taught by Krueger (outside meaning ambient para[0037]).
As to claim 5/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1 except for the pressure equalization assembly comprises a second valve configured to transition from a non-conductive state into a conductive state when a pressure in the expansion tank is greater than a pressure in the ambient environment by at least a specified second amount in order to at least partially cause the pressure equalization in case of a positive pressure in the expansion tank, wherein the specified second amount is not equal to zero.
Krueger shows the pressure equalization assembly comprises a second valve 11A configured to transition from a non-conductive state into a conductive state when a pressure in the expansion tank 8 is greater than a pressure in the ambient environment by at least a specified second amount in order to at least partially cause the pressure equalization in case of a positive pressure in the expansion tank 8, wherein the specified second amount is not equal to zero (vent valve 11 has spring 15 closure that opens in the range of higher 1-1.5 bar pressure in the expansion tank 8 than the atmosphere and is closed with less of a pressure difference see FIG. 2 above and FIG. 3, 5 and para[0035],[0037],[0039],[0042]).
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 cooling circuit 6 of Steinz in view of Krueger and Bessho to have the pressure equalization assembly comprises a second valve 11A configured to transition from a non-conductive state into a conductive state when a pressure in the expansion tank 8 is greater than a pressure in the ambient environment by at least a specified second amount in order to at least partially cause the pressure equalization in case of a positive pressure in the expansion tank 8, wherein the specified second amount is not equal to zero as taught by Krueger, for the advantageous benefit of equalizing the pressure between the first cooling circuit 6 and the outside as taught by Krueger (outside meaning ambient para[0015],[0037]).
As to claim 6/5/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1 except for the second valve comprises a second spring, and wherein the specified second amount is influenced by a spring force of the second spring.
Krueger shows (FIG. 2, 3, 5, 6) the second valve 11A comprises a second spring 15, and wherein the specified second amount is influenced by a spring force of the second spring 15 (vent valve 11 has spring 15 closure that opens in the range of higher 1-1.5 bar pressure difference and is closed with less of a pressure difference see FIG. 2 above and FIG. 3, 5 and para[0041],[0042]).
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 cooling circuit 6 of Steinz in view of Krueger and Bessho to have the second valve 11A comprises a second spring 15, and wherein the specified second amount is influenced by a spring force of the second spring 15 as taught by Krueger, for the advantageous benefit of equalizing the pressure between the first cooling circuit 6 and the outside as taught by Krueger (outside meaning ambient para[0015],[0037]).
As to claim 8/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1 except for the first valve comprises a first spring, and wherein the specified first amount is influenced by a spring force of the first spring.
Krueger shows the first valve 11B comprises a first spring 15, and wherein the specified first amount is influenced by a spring force of the first spring 15 (vent valve 11 has spring 15 closure that opens in the range of higher 1-1.5 bar pressure difference and is closed with less of a pressure difference see FIG. 2 above and FIG. 3, 5 and para[0041],[0042]).
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 cooling circuit 6 of Steinz in view of Krueger to have the first valve 11B comprises a first spring 15, and wherein the specified first amount is influenced by a spring force of the first spring 15 as taught by Krueger, for the advantageous benefit of equalizing the pressure between the first cooling circuit 6 and the outside as taught by Krueger (outside meaning ambient para[0015],[0037] ).
As to claim 10/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1 except for the pressure equalization assembly comprises a second filter apparatus configured to reduce or prevent an entry of dirt through air entering the expansion tank from the ambient environment.
Krueger shows (FIG. 6) the pressure equalization assembly comprises a second filter apparatus 21 configured to reduce or prevent an entry of dirt through air entering the expansion tank 8 from the ambient environment (second membrane para[0044]).
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 cooling circuit 6 of Steinz in view of Krueger and Bessho to have the pressure equalization assembly comprises a second filter apparatus 21 configured to reduce or prevent an entry of dirt through air entering the expansion tank 8 from the ambient environment as taught by Krueger, for the advantageous benefit of preventing liquid or dirt from entering the pressure equalization assembly from the outside as taught by Krueger (para[0044]).
As to claim 14/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1 and Steinz further shows an electric vehicle having the drive unit according to claim 1 (para[0002]).
As to claim 21/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1 except for the first heat exchanger is configured to transfer heat between the first cooling circuit and the third cooling circuit and to keep the first cooling circuit and the third cooling circuit fluidically separate, and wherein the second heat exchanger is configured to transfer heat between the second cooling circuit and the third cooling circuit and to keep the second cooling circuit and the third cooling circuit fluidically separate.
Bessho shows (FIG. 1) the first heat exchanger H1 is configured to transfer heat between the first cooling circuit 12 and the third cooling circuit 81 and to keep the first cooling circuit 12 and the third cooling circuit 81 fluidically separate, and wherein the second heat exchanger H3 is configured to transfer heat between the second cooling circuit 13 and the third cooling circuit 81 and to keep the second cooling circuit 13 and the third cooling circuit 81 fluidically separate.
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 cooling circuit 6 of Steinz in view of Krueger and Bessho to have the first heat exchanger 10C is configured to transfer heat between the first cooling circuit 6 and the third cooling circuit 81 and to keep the first cooling circuit 6 and the third cooling circuit 81 fluidically separate, and wherein the second heat exchanger 10B is configured to transfer heat between the second cooling circuit 7 and the third cooling circuit 81 and to keep the second cooling circuit 7 and the third cooling circuit 81 fluidically separate as taught by Bessho, for the advantageous benefit of stably cooling the electric machine motor as taught by Bessho (para[0007]).
Claim(s) 9 is rejected under 35 U.S.C. 103 as being unpatentable over Steinz et al. (US 2021/0006132 A1, hereinafter Steinz) in view of Krueger (DE 102015109690 A1) and Bessho (JP2021024447 A) and Viereck et al. (US 2007/0199443 A1, hereinafter Viereck).
As to claim 9/1, Steinz in view of Krueger and Bessho was discussed above with respect to claim 1 except for the pressure equalization assembly comprises a dehumidification apparatus configured to perform a dehumidification of air entering the expansion tank from the ambient environment.
Viereck shows the pressure equalization assembly comprises a dehumidification apparatus configured to perform a dehumidification of air entering the expansion tank from the ambient environment (oil expansion vessel has air dehumidifier para[0001],[002]).
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 cooling circuit 6 of Steinz in view of Krueger and Bessho to have the pressure equalization assembly comprises a dehumidification apparatus configured to perform a dehumidification of air entering the expansion tank from the ambient environment as taught by Viereck, for the advantageous benefit of drying air having an unacceptable moisture content before inducting the air into the pressure equalization assembly as taught by Viereck (para[0002]).
Allowable Subject Matter
Claims 15-20 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.
The following is a statement of reasons for the indication of allowable subject matter:
The prior art does not show or suggest an activated carbon filter in the third cooling circuit as recited in claim 15.
The prior art does not show or suggest the third cooling circuit includes a pulse inverter heat exchanger as recited in claim 16. Dependent claims 17-18 have allowable subject matter for the same reason.
The prior art does not show or suggest the order of devices in the flow path as recited in claim 19. Dependent claim 20 has allowable subject matter for the same reason.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: Bessho (JP2021024447 A) shows separate pumps in each of three cooling circuits (para [0029]).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ROBERT E MATES whose telephone number is (571)270-5293. The examiner can normally be reached M to F 12:00pm to 8pm.
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/ROBERT E MATES/Examiner, Art Unit 2834
/TULSIDAS C PATEL/Supervisory Patent Examiner, Art Unit 2834