DETAILED ACTION
Notice of Pre-AIA or AIA Status
This action is in response to the claims set filed 10/07/2025 following the Non-Final Rejection of 06/11/2025. Claims 13 and 18 were amended. Claims 13-24 are currently pending.
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 Arguments
Applicant’s arguments, see Remarks, filed 10/07/2025, with respect to claims rejected under 35 USC § 112(b) and 35 USC § 101 have been fully considered and are persuasive. These rejections of 06/11/2025 have been withdrawn.
The claims as now amended is now sufficiently tied to a practical application. Specifically, the method for identifying an accumulation of ice on at least one rotor blade of a wind turbine includes the step of “detecting vibration of the at least one rotor blade during operation of the wind turbine in a subsequent state and cinoarubg characteristic properties of the subsequent detected vibrations by comparing the subsequent characteristic properties with the reference properties to indicate that the at least one rotor blade is free of ice in the subsequent state”.
Applicant’s arguments, see Remarks, filed 10/07/2025, with respect to the rejection(s) of claim(s) under 35 USC § 103 have been fully considered and are persuasive. Therefore, the rejections as previously presented have been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of the amendments made to the claim. Upon further review of Müller, it was determined that the detected vibrations are analogous to the subsequent detected vibrations of step f of the instant claims and that the reference vibrations are analogous to the detected vibrations in step e of the instant claims
Applicant's point on page 5 of Remarks that “with the claimed invention, steps (a)-(d) of claim 13 are performed to calibrate the device and not to detect an actual icing situation as is the case with Alfred. After installation of a wind turbine, steps (a)-(d) are repeatedly performed in a presumptive ice free state until a measured electrical output of the wind corresponds to a calculated electrical output of the turbine, thus indicating that the at least one rotor blade of the wind turbine is free of ice” and that “the calibration/confirmation method of claim 13 is not disclosed or suggested by the combined teachings of Mueller and Alfred” was not found persuasive by the Examiner.
While it is accurate that neither Müller (US 2019/0368472) nor Alfred (DE102010015595A1) independently disclose the claimed invention. The claimed invention was found to be obvious over Müller in view of Alfred. Müller discloses that it is known to compare detected vibrations against reference vibrations, the reference vibrations being a basic value of a natural frequency in a state free of ice attachment and can be determined by a reference measurement of the natural frequency in this state free of ice attachment. Alfred discloses that it is known to compare an actual measured power output against a calculated power output (determined from operational conditions of the wind turbine) so as to determine whether ice formation is present on the wind turbine blades. In carrying out the reference measurement for Müller, it would have been obvious to utilize a known method (such as the one disclosed by Alfred) of ice detection to determine whether a state free of ice attachment exists so that the reference measurement can be undertaken. As such, claim 13 is obvious over Müller in view of Alfred.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., “steps (a)-(d) are repeatedly performed in a presumptive ice free state until a measured electrical output of the wind corresponds to a calculated electrical output of the turbine”) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Claim Objections
Claim 15 is objected to because of the following informalities:
Claim 15 recites “the calculated electrical output” but should likely read “the calculated expected electrical output”.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
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.
Claims 13-24 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding Claim 13 lines 19-20, the limitation “cinoarubg characteristic properties of the subsequent detected vibrations” renders the claim indefinite since it is unclear what is being established by this limitation. For prior art purposes, the word “cinoarubg” is being interpreted as analogous to “evaluating” as this appears to be in line with the instant specification.
Claims 14-24 are also rejected due to their respective dependency upon claim 13 rejected above.
Claim Rejections - 35 USC § 103
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(s) 13-19 and 21-24 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 2019/0368472, herein referenced as Müller, in view of DE102010015595A1 (first cited in the Office Action of 09/10/2024), herein referenced as Alfred.
Regarding Claim 13, Müller comprises a method for identifying an accumulation of ice (“device and method for recognizing the attachment of ice to a structure of an edifice” title) on at least one rotor blade of a wind turbine (100 fig. 2), comprising the steps of
(a) [operation of the wind turbine in a presumptive ice free state] (“reference natural frequency, for example, is a basic value of a natural frequency of the structure 110 in a state free of ice attachment. The basic value may be determined, for example by a reference measurement of the natural frequency in the state free of ice attachment” pr. 31)
(e) detecting vibrations of the at least one rotor blade (“acceleration sensor 10 is arranged and configured in a manner to detect an acceleration on the structure 110. For example, the acceleration sensor 10 is arranged in a rotor blade or on a rotor blade of a wind turbine” pr. 17) during operation of the wind turbine (“basic value may be determined, for example, by a reference measurement of the natural frequency in the state free of ice attachment” pr. 31) and storing characteristic properties of the detected vibrations as reference properties for the device in the presumptive ice free state (“ reference natural frequency, for example, is a basic value of a natural frequency of the structure 110 in a state free of ice attachment. The basic value may be determined, for example, by a reference measurement of the natural frequency in the state free of ice attachment or by simulation” pr. 31; “a state free of ice attachment” being analogous to a presumptive ice free state); and
(f) detecting vibration of the at least one rotor blade during operation of the wind turbine in a subsequent state (“the indirect detecting of the attachment of ice to the structure 110 comprises comparing the determined at least one natural frequency with at least one reference natural frequency, and determining a shift between the determined at least one natural frequency and the at least one reference natural frequency” pr. 30, since the reference natural frequency would is a stored value which is determined by a reference measurement, as disclosed in pr. 31, the determined at least one natural frequency would be after (i.e. subsequent from) the at least one reference natural frequency that it is compared to) and cinoarubg (this is being interpreted to mean evaluating based upon the instant specification) characteristic properties of the subsequent detected vibrations (“For detecting the at least one natural frequency, the evaluation device 30, for example, is configured to transform a measurement value progress of the acceleration sensor into the frequency domain, for example, by a Fourier transform or another suitable integral transformation. A natural frequency of the structure 110 may show, for example, as a frequency excess (a peak) in the transformed signal.” Pr. 21) by comparing the subsequent characteristic properties with the reference properties to indicate that the at least one rotor blade is free of ice in the subsequent state (“indirect detecting of the attachment of ice to the structure 110 comprises comparing the determined at least one natural frequency with at least one reference natural frequency” pr. 30).
While Müller discloses detecting vibrations for an at least one reference natural frequency in a state free of ice attachment, Müller fails to explicitly anticipate (a) monitoring operating and ambient conditions during operation of the wind turbine in [the] presumptive ice-free state;
(b) calculating an expected electrical output of the wind turbine under the presumptive ice-free operating and ambient conditions;
(c) measuring an actual electrical output generated by the wind turbine during the operation in the presumptive ice-free state;
(d) comparing the calculated expected electrical output of the wind turbine with the actual electrical output to indicate whether the at least one rotor blade is free of ice in accordance with the comparison of the calculated expected electrical output and the actual electrical output of the wind turbine.
Müller and Alfred are considered analogous art since they relate to the field of endeavor of wind turbines.
Alfred teaches of a method comprising the steps of
(a) monitoring operating and ambient conditions during operation of the wind turbine (“the operating parameter recorded is the power, in particular the power generated by the wind turbine, i.e. by the generator, and/or that the current wind speed is recorded and the reference variable is dependent on the wind speed” pr. 22, “Known fluctuations in air density that occur, for example, at different ambient temperatures, such as 3°C and 30°C, can be taken into account by an appropriate adjustment factor” pr. 33; “a temperature is detected at or near the wind turbine, in particular an outside temperature” pr. 37) in a presumptive ice-free state (“At least one operating parameter of this operating point is recorded” pr. 11, this section establishes that the operating parameter(s) of the wind turbine are generally monitored and would therefore also be monitored in a presumptive ice-free state of the wind turbine);
(b) calculating an expected electrical output of the wind turbine under the presumptive ice-free operating and ambient conditions (“For this measured wind speed value, a reference value for the power that usually occurs under normal conditions is stored in a characteristic curve or a reference table - so-called lookup table” pr. 23);
(c) measuring an actual electrical output generated by the wind turbine (“At least one operating parameter of this operating point is recorded. For example, the electrical power delivered by the generator is recorded and forms the recorded operating parameter” pr. 11) during the operation in the presumptive ice-free state (this measuring occurs generally during operation of the wind turbine and would also occur during the presumptive ice-free state);
(d) comparing the calculated expected electrical output of the wind turbine with the actual electrical output (“The recorded power that resulted when setting the operating point is compared with the power value stored for the current wind speed” pr. 23) to indicate whether the at least one rotor blade is free of ice (“The underlying idea here is that an optimal power conversion of the prevailing wind into electrical power to be delivered by the generator is achieved with rotor blades without ice build-up. If small deviations occur between the recorded power and the reference power - for the example of recording the output power of the generator as a recorded operating parameter - it is initially assumed that this is due to natural fluctuations or changes in some boundary parameters, such as air density. For such small deviations, the wind turbine will continue to operate unchanged” pr. 18; “If the current operating point is based on normal boundary conditions, in particular no icing, the power that should be achieved when setting the operating point is approximately equal to the power stored as a reference value for the current wind speed. Minor deviations can be tolerated” pr. 24, “if the recorded operating parameter lies outside the first tolerance range and thus exceeds a first predetermined deviation, an unusual circumstance must be assumed, such as ice formation” pr. 19, the assumed ice formation for when larger deviations which are outside a first tolerance range occur would mean that deviations within the first tolerance range, would be analogous to the blade being free of ice) in accordance with the comparison of the calculated expected electrical output and the actual electrical output of the wind turbine (“The recorded power that resulted when setting the operating point is compared with the power value stored for the current wind speed” pr. 23).
Therefore, it would have been obvious before the effective filing date of invention to one of ordinary skill in the art to have modified the reference measurement of Müller with the means for determining icing of a wind turbine disclosed by Alfred so as to obtain benefit of ‘a means for determining an icing event versus normal operation’ as taught by Alfred. This would be beneficial for the “reference measurement of the natural frequency in the state free of ice attachment” disclosed in pr. 31 by Müller as the means taught by Alfred can be used to establish/determine the wind turbine as being in a state free of ice attachment (i.e. unchanged/normal operation) for the reference natural frequency measurement(s).
Regarding Claim 14, the combination of Müller and Alfred comprises the method as defined in claim 13, wherein the operating and ambient conditions comprise at least one of a wind speed (“the prevailing wind speed is measured” pr. 23 of Alfred, as used to modify Müller), an ambient and/or blade temperature, an angle of attack of at least one rotor blade, and a rotational speed of a rotor of the wind turbine.
Regarding Claim 15, the combination of Müller and Alfred comprises the method as defined in claim 13, in which the calculated electrical output is determined using a model that reflects measured power outputs at measured operating and ambient conditions (“the reference quantity is stored as a reference characteristic curve dependent on the wind speed” pr. 22 of Alfred, as used to modify Müller, and “For this measured wind speed value, a reference value for the power that usually occurs under normal conditions is stored in a characteristic curve or a reference table - so-called lookup table” pr. 23 of Alfred, as used to modify Müller).
Regarding Claim 16, the combination of Müller and Alfred comprises the method as defined in claim 15, in which the power outputs of a further wind turbine comparable to the wind turbine are measured (“A wind speed-dependent reference value is preferably used as the reference characteristic curve. For each system type, such a reference characteristic curve, such as a wind speed-dependent power curve, can be stored at the factory as a standard characteristic curve - also known as a default characteristic curve. This standard reference curve is initially used immediately after the wind turbine is put into operation” pr. 33 of Alfred, as used to modify Müller; the default/standard reference power curve would represent a further wind turbine (i.e. an ideal/standard wind turbine) during the comparison step).
Regarding Claim 17, the combination of Müller and Alfred comprises the method as defined in claim 15, in which the power outputs are measured at the wind turbine itself (“This standard reference curve is initially used immediately after the wind turbine is put into operation […] each wind turbine adapts this standard characteristic curve during its operation. This is done by using measured values under assumed normal boundary conditions of the wind turbine, in particular under conditions where icing can be excluded. The measured values are then processed into a corresponding reference curve” pr. 33 of Alfred, as used to modify Müller).
Regarding Claim 18, the combination of Müller and Alfred comprises the method as defined in claim 13, wherein in said comparing step, a quotient is formed between the actual electrical output and the calculated electrical output of the wind turbine (“the recorded power that resulted when setting the operating point is compared with the power value stored for the current wind speed” in pr. 23 aa “if larger deviations [relative to minor deviations] occur, slight icing can be assumed and heating of the rotor blade is initiated” pr. 24 of Alfred, as used to modify Müller; the deviation in percentage form would be represent the claimed quotient, e.g.: recorded power is 95% of reference power at the measured wind speed), said quotient is compared with a predetermined threshold value (“if larger deviations [than minor deviations] occur, slight icing can be assumed and heating of the rotor blade is initiated.” Pr. 24 of Alfred and “If the detected operating parameter now exceeds a predetermined deviation from the detected reference value” in pr. 13 of Alfred as used to modify Müller above; the predetermined deviation or larger deviations (greater than minor deviations) would represent a threshold value). (100% minus the percent deviation would be analogous to the quotient claimed above)
Regarding Claim 19, the combination of Müller and Alfred comprises the method as define in claim 18, wherein the at least one rotor blade is indicated as being free of ice when the threshold is exceeded (“if larger deviations [than minor deviations] occur, slight icing can be assumed and heating of the rotor blade is initiated.” Pr. 24 of Alfred and “If the detected operating parameter now exceeds a predetermined deviation from the detected reference value, at least one rotor blade is heated” in pr. 13 of Alfred as used to modify Müller above; the predetermined deviation or larger deviations (greater than minor deviations) would represent a range where smaller deviations would be assumed to be free of ice as the larger deviations are assumed to be icing, this assumption of being free of ice would be analogous to an indication that the blade is free of ice; this disclosure from the prior art is merely a different way of explaining the claim limitation above)
Regarding Claim 21, the combination of Müller and Alfred comprises the method as defined in claim 13, wherein the characteristic properties of the vibrations relate to a frequency and/or amplitude of a vibration state (“For detecting the at least one natural frequency, the evaluation device 30, for example, is configured to transform a measurement value progress of the acceleration sensor into the frequency domain, for example, by a Fourier transform or another suitable integral transformation.” pr. 21 of Müller, as modified by Alfred).
Regarding Claim 22, the combination of Müller and Alfred comprises the method as defined in claim 21, wherein the vibration state corresponds to that of a maximum in a vibration spectrum of the vibrations (“A natural frequency of the structure 110 may show, for example, as a frequency excess (a peak) in the transformed signal. The disclosure is not restricted to a single natural frequency, and a plurality of natural frequencies of the structure 110 may also be referred to for the indirect detection” pr. 21 of Müller, as modified by Alfred; the frequency excess/peak would be analogous to the maximum in a vibration spectrum).
Regarding Claim 23, the combination of Müller and Alfred comprises the method as defined in claim 13, wherein the characteristic properties of the vibrations (“For detecting the at least one natural frequency, the evaluation device 30, for example, is configured to transform a measurement value progress of the acceleration sensor into the frequency domain, for example, by a Fourier transform or another suitable integral transformation. A natural frequency of the structure 110 may show, for example, as a frequency excess (a peak) in the transformed signal” pr. 21 of Müller, as modified by Alfred) relate to at least one frequency range from a spectrum of the vibrations (“The disclosure is not restricted to a single natural frequency, and a plurality of natural frequencies of the structure 110 may also be referred to for the indirect detection” pr. 21 of Müller, as modified by Alfred).
Regarding Claim 24, the combination of Müller and Alfred comprises an apparatus (“a device and a method for recognising the attachment of ice to a structure (110)” abstract of Müller) for detecting an accumulation of ice on at least one rotor blade of a wind turbine (see structure 110 formed as a blade of the wind turbine 100 in fig. 2 of Müller), comprising
a monitoring device (“a device and a method for recognising the attachment of ice to a structure (110)” abstract of Müller) in which ice is detected on the basis of natural vibration measurements on the at least one rotor blade (see acceleration sensor 10 in fig. 2 of Müller; “an evaluation device (30) for determining at least one natural frequency of the structure (110) from the detected acceleration, wherein the evaluation device (30) is configured to indirectly detect attachment of ice to said structure (110) on the basis of the determined natural frequency of the structure (110)” abstract of Müller), said monitoring device including an evaluation unit (“an evaluation device (30) for determining at least one natural frequency of the structure (110) from the detected acceleration, wherein the evaluation device (30) is configured to indirectly detect attachment of ice to said structure (110) on the basis of the determined natural frequency of the structure (110)” abstract of Müller) configured to implement the teaching method according claim 13 (see rejection of claim 13 above over Müller as modified by Alfred).
Claim(s) 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over the combination of Müller and Alfred as applied to claim 19 above, and further in view of US 2019/0323485, herein referenced as Gregory.
Regarding Claim 20, the combination of Müller and Alfred comprises the method as defined in claim 19, but fail to teach wherein the threshold is between 60% and 95%.
Gregory is considered analogous art since it relates to the field of endeavor of wind turbines.
Gregory teaches that “to determine whether there are icing conditions, a processor compares the measured power curve 508 to the reference power curve 506. If the measured power curve 508 deviates from the reference power curve 506 by a given amount, then the processor determines that there are icing conditions. For example, the measured power curve 508 deviating from the reference power curve 506 by 5-30% corresponds to an icing condition”.
Therefore, it would have been obvious before the effective filing date of invention to one of ordinary skill in the art to have modified the combination of Müller and Alfred to have the deviation between a measured power curve and a reference power curve of 5-30% disclosed by Gregory since this level of deviation “corresponds to an icing condition” as taught by Gregory. In the manner claimed by Applicant, a measured power level which is 70% to 95% of the reference power level would represent the range of possible threshold, values above the threshold would be assumed free of ice).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 12012937 – discloses a controller for detecting an ice event at a wind farm, also states that one way to ensure that the collected wind turbine performance data is ice-free, i.e. not affected by ice, is to remove all data that has been obtained when the temperature at a wind farm is such that ice may be present. Typically, this is achieved by discarding all of the collected performance data below a given temperature threshold. This suffers the disadvantage of excessive loss of performance data, in particular on wind farms where the ambient temperature is often or even always below the given temperature threshold. Such high levels of data loss can make validation of wind turbine upgrades difficult or even impossible.
US 9518561 – US patent grant of the foreign filing of Alfred cited above.
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/W.L.F./Examiner, Art Unit 3745
/COURTNEY D HEINLE/Supervisory Patent Examiner, Art Unit 3745