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 .
Response to Amendment
Regarding objections to the drawings:
The drawings were objected to due to multiple informalities. The replacement drawings received 3/17/2025 corrected the informalities, therefore the objection was withdrawn.
Regarding objections to the claims:
Claim 11 was objected to due to an informality. The Applicant amended the claim to correct the informality, therefore the objection was withdrawn.
Regarding rejections of the claims under §§102 and 103:
Claims 1-2 and 6-8 were rejected as being anticipated by Vestas. Claims 3-5 and 9-10 were rejected as being obvious over Vestas in view of Ahn. Claim 11 was rejected as being obvious over Vestas in view of Lendenmann. The Applicant amended claims 1, and 4-5 and canceled claims 2-3.
Response to Arguments
Applicant’s arguments with respect to claims 1 and 4-11 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
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.
Claims 1 and 4-10 are rejected under 35 U.S.C. 103 as being unpatentable over United Kingdom Patent No. 2461533 to Vestas Wind Systems A/S (provided by Applicant on 6/2/2023; hereinafter Vestas) in view of Chinese Patent No. 111193331 to Tan et al. (hereinafter Tan) and European Patent No. 1 445 997 to Ahn et al. (hereinafter Ahn).
Regarding claim 1, Vestas teaches a slip ring unit (FIG. 2; 30, 32, 36, 38) for an electric generator (FIG. 1, 16) comprising:
a slip ring (FIG. 5, 50) attachable to a rotor shaft (Page 6 lines 1-5) of the electric generator),
a plurality of sliding contacts (FIG. 3, 44) arranged along a circumference of the slip ring to provide an electrical connection with the slip ring (Page 6 lines 15-20),
a temperature sensor (Page 10 lines 19-22) for measuring a temperature inside the slip ring unit,
at least one fan (Page 10 lines 16-19) for providing a cooling flow in the slip ring unit, and
a controller (Page 4 lines 4-5) connected to the at least one fan for controlling a cooling flow rate generated by the at least one fan (Page 10 lines 27-29), the controller being connected to the at least one temperature sensor (Page 10 lines 19-26),
wherein the at least one temperature sensor is attached to at least a holder (Page 10 lines 19-20) for supporting the plurality of sliding contacts and the controller is configured in such a way that the cooling flow rate is generated depending on the temperature measured by the at least one temperature sensor (Page 10 lines 17-26);
wherein the controller comprises an input for receiving a temperature signal from the at least one temperature sensor (Page 10 lines 19-22) and an output for sending a controlling signal to the at least one fan (Page 10 lines 16-19),
wherein the controlling signal to be applied to an electric motor of the at least one fan, and by variating the controlling signal the speed of a motor of the at least one fan is changed (Page 10 lines 16-19).
Vestas does not teach a plurality of holders that are arcuated plates coaxial with a rotational axis, wherein the plurality of holders are axially distributed and distanced along the rotational axis, and each of the plurality of holders support a respective plurality of sliding contacts; a plurality of temperature sensors, wherein one temperature sensor is attached to each holder; and the controlling signal being a proportional function of the temperature signal.
However, Tan teaches a slip ring assembly having a plurality of holders that are arcuated plates (FIG. 2, 20) coaxial with a rotational axis, wherein the plurality of holders are axially distributed and distanced along the rotational axis (FIG. 1), and each of the plurality of holders support a respective plurality of sliding contacts (FIG. 3, 30); and a plurality of temperature sensors (FIG. 5, 303), wherein one temperature sensor is attached to each holder (Paragraph [0039]).
Therefore, 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 slip ring unit of Vestas with the holders and temperature sensors of Tan to implement a more accurate temperature detection system of the slip ring unit that can more adequately provide cooling for the system.
Vestas in view of Tan does not teach the controlling signal being proportional to the temperature signal.
However, Ahn teaches a fan control unit for thermal management wherein the relationship between a temperature signal from a temperature sensor and a controlling signal for a fan is proportional (FIG. 2, 3; Paragraph [0013]).
Therefore, 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 slip ring unit of Vestas in view of Tan with the proportional controlling signal of Ahn as it seeks to maximize efficiency of the slip ring cooling unit (Paragraph [0020]).
Regarding claim 4, Vestas in view of Tan and Ahn teaches the slip ring unit according to claim 1, wherein Ahn further teaches the controlling signal being linearly proportional to the temperature signal (FIG. 2, 3; Paragraph [0013]).
Regarding claim 5, Vestas in view of Tan and Ahn teaches the slip ring unit according to claim 1, wherein Ahn further teaches the controlling signal being a voltage signal (Paragraph [0013]).
Regarding claim 6, Vestas in view of Tan and Ahn teaches an electric generator (Vestas FIG. 1, 16) comprising a rotor (Vestas FIG. 1, 14), a stator (Vestas FIG. 1, 18), a rotor shaft (Vestas Page 10 lines 16-19) and a slip ring unit according to claim 1.
Regarding claim 7, Vestas in view of Tan and Ahn teaches a wind turbine (Vestas Abstract) comprising an electric generator according to claim 6.
Regarding claim 8, Vestas in view of Tan and Ahn teaches an operating method for operating a slip ring unit according to claim 1, Vestas further teaching the method comprising:
measuring a temperature inside the slip ring unit with the at least one temperature sensor (Page 10 lines 19-22),
providing a cooling flow in the slip ring unit (Page 10 lines 16-19), and
controlling the cooling flow rate depending on the temperature measured by the at least one temperature sensor (Page 10 lines 22-29).
Regarding claim 9, Vestas in view of Tan and Ahn teaches the operating method according to claim 8, wherein Ahn further teaches the cooling flow rate being proportional to the temperature signal (FIG. 2, 3; Paragraph [0013]).
Regarding claim 10, Vestas in view of Tan and Ahn teaches the operating method according to claim 9, wherein Ahn further teaches the cooling flow rate being linearly proportional to the temperature signal (FIG. 2, 3; Paragraph [0013]).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Vestas in view of Tan and Ahn and in further view of U.S. Patent No. 9,112,394 to Lendenmann et al. (hereinafter Lendenmann; cited by Applicant on 6/2/2023).
Regarding claim 11, Vestas in view of Tan and Ahn teaches the operating method according to claim 8, wherein Vestas teaching the method further comprises:
measuring a rotor speed and a rotor current (Page 9 lines 21-23);
calculating a required air flow in the slip ring unit (Page 10 lines 16-29);
determining at least one wear-ratio curve for the sliding contacts of the slip ring unit (Page 9 line 5-8); and
determining an expected lifetime of the sliding contacts by using the at least one wear-ratio curve and the temperature measured inside the slip ring unit (Page 10 lines 2-9).
Vestas in view of Tan and Ahn does not teach calculating thermal losses in the slip ring unit and calculating a plurality of temperatures in a respective plurality of points of the slip ring unit.
However, Lendenmann teaches a cooling system for an electrical machine wherein thermal losses are calculated (Column 5 lines 40-61) and a plurality of temperatures in a respective plurality of points of the electrical machine are calculated (Column 5 lines 56-61).
Therefore, 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 operating method of Vestas in view of Tan and Ahn with the thermal modeling of Lendenmann in order to provide a more accurate thermal model of the slip ring unit to better determine a wear of the sliding contacts and ensure proper operation of the slip ring unit.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOSHUA KIEL MIGUEL RODRIGUEZ whose telephone number is (571)272-9881. The examiner can normally be reached Monday - Friday 9:30am - 7:00pm ET.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Tulsidas Patel can be reached at (571) 272-2098. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JOSHUA KIEL M RODRIGUEZ/Examiner, Art Unit 2834
/TULSIDAS C PATEL/Supervisory Patent Examiner, Art Unit 2834