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 .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on July 12, 2024 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Response to Amendment
The Amendment filed March 18, 2026 has been entered. Claims 1-14 remain pending in the application. Claims 11 & 14 are amended. Applicant’s amendments to the Claims have overcome each and every objection previously set forth in the Non-Final Office Action mailed December 19, 2025, hereafter referred to as the Non-Final Office Action.
Response to Arguments
Applicant's arguments, please refer to pp. 7-9 of Applicant’s remarks, filed March 18, 2026 have been entered and fully considered. In light of the previously presented claims, the Applicant has presented a set of argument(s) pointing out their rationale of how the prior art reference(s) made of record in the most recent Office Action do not teach the currently recited claim limitations. Applicant’s arguments have been fully considered but they are not persuasive.
In response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007).
In this case, Applicant in their submitted response presents the argument that the prior art references, Moore et al. (US3967051), in view of Clarke et al. (US4963819), to include the referenced prior art reference Quirk et al. (US3769447), do not teach, disclose, and/or suggest, individually, or in combination, the limitation of the structure of a sensored bushing comprising a first spacer “mechanically connected to the sensing electrode and to the shield electrode to maintain the sensing electrode and the shield electrode in a fixed spatial relation to each other, wherein the first spacer is of annular shape and comprises a flat major surface delimited radially by an outer perimetral edge and an inner perimetral edge,” recited in the previously presented independent claim 1. Applicant has emphasized, specifically, “the recited sensored bushing structure including an annular spacer having a flat major surface disposed between a sensing electrode and a shield electrode.”
The examiner respectfully disagrees and would like to break the argument presented into two sections. The first part the Examiner would like to highlight is in regard to the ”annular shape and having a flat major surface”, please refer to pp. 7-9 of Applicant’s remarks, where the Applicant states that the prior art reference, Moore, discloses “spacers ‘28’ at col 4 lines 60-69 in the context of describing content of prior art (the Quirk ‘447 reference, for example)”, and that the “spacers in Quirk are not illustrated nor described as having a flat major surface”, instead “the spacer geometry is described as “dimples”, “insulating buttons or spacer sticks”. The Examiner appreciates the explanation and the evidence provided; however, it is noted that the claims are examined given the broadest reasonable interpretation. In the immediate case of this application, the Examiner has taken the interpretation that “an annular spacer having a flat major surface”, as disclosed by Moore, who further references Quirk in regard to these limitations, please refer to the Non-Final OA pp. 3-7.
This leads to the second part the Examiner would like to highlight, how the prior art reference, Moore, reads on the claims. The Examiner mapped the “wherein the first spacer is of annular shape and comprises a flat major surface delimited radially by an outer perimetral edge and an inner perimetral edge,” (Fig. 1; [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]), including the Non-Final OA pp. 3-7, where page 7 further discloses [Col. 3, ll. 12-18], mentioning an “overall tapered cylindrical, or conical shape, and the mesh members 28 and 30, are coated with an epoxy resin, where the “penetration by the epoxy…form a substantially voidless bond”, and further stating that the mesh members are “treated prior to encapsulation to make them rigid for the purpose of maintaining separation distances”. Therefore the spacers in Moore, could be modified to have a flat surface due to the epoxy resin providing an overall rigid structure, that would in essence “encapsulate” the members, filling the voids, forming the “flat major surface”, and Figure 1 further depicts the mesh members (spacers 32 & 36). Moore uses a tapered mesh because a solid flat surface would block the axial flow of the injected epoxy resin during the casting process, and defeating the manufacturing methodology. Further, modifying the spacer in Moore, in view of Quirk, to lead to the “annular shape and having a flat major surface” is a matter of design choice.
As referenced by prior art reference, Moore, in (Fig. 1; [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]: standard spacers 28 “taught by U.S. Pat. No. 3,769,447” incorporated by reference, which are included in Moore’s prior art reference, have an annular shape because it is symmetric as depicted in the section of Fig. 1, with flat major surfaces, where Moore discloses the alternative or supplementary use of the standard spacers at the top and bottom to ensure separation of the use of spacers is well-known in the present field). Quirk mentions that “any interfaces not eliminated will trap air which will induce the start of corona at high voltages” ([Col. 1, ll. 46-50]), and further discloses the shape and flat surface ([Col. 4, ll. 24-37]), where “all surfaces on the underside of the sheet tend to have a rounded effect will discourage the formation of corona on the underside of the sheet” and “it is seen that the top surface 30 of the material is flat and provides a good surface for applying the conductive elements…”. Combining the teachings of Quirk into Moore, would be obvious to a POSITA, and by implementing epoxy, as taught by Moore, and combining with Quirk’s teachings (e.g., annular shape because they extend around the conductor and appear symmetric in a section of the bushing in Fig. 1 and a flat surface), the combination would result in a spacer with an annular shape comprising a flat major surface without “dimples” or “insulating buttons or spacer sticks”.
In regard to prior art reference, Clarke, as referenced by the Applicant, the reference further overcomes any deficiencies of Moore and/or Moore/Quirk, further stating that it utilizes “conductive polymeric CNTM tubings 20…forming guard rings…clamping…two aluminum half-shells to form a housing 30 that seals at each end…” in ([Col. 1, ll. 31-34 & 51-67], [Col. 2, ll. 49-64], [Col. 9, ll. 18-62] & [Col. 14, ll. 3-14]). If Clarke were to be incorporated into the combination of references, again would lead a POSITA to a design choice, and would be obvious to modify the spacers, interpreted as the guard rings, to have the “annular shape and having a flat major surface.” Based on the reasoning provided above, the Examiner believes Moore/Quirk, in view of Clarke, teach the limitations recited in previously presented independent claim 1. Therefore, the rejection(s) independent claim 1, and dependent claims 2-13, which depend from and incorporate the limitations of independent claim 1, are respectively maintained.
In response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007).
In this case, Applicant in their submitted response presents the argument that the prior art references, Moore et al. (US3967051), in view of Clarke et al. (US4963819), to include the referenced prior art reference Quirk et al. (US3769447), do not teach, disclose, and/or suggest, individually, or in combination, the limitation of the structure of a sensored bushing comprising a first spacer “mechanically connected to the sensing electrode and to the shield electrode to maintain the sensing electrode and the shield electrode in a fixed spatial relation to each other, wherein the first spacer is of annular shape and comprises a flat major surface delimited radially by an outer perimetral edge and an inner perimetral edge,” recited in the previously presented independent claim 1. Applicant has emphasized, that the prior art references do not teach, disclose, and/or suggest, “a sensored bushing with spacers of “annular shape and having a flat major surface” embedded in casting material and arranged between a sensing electrode and a shield electrode”.
The examiner respectfully disagrees and would like to break the argument presented into two sections. The first part the Examiner would like to highlight is in regard to the ”annular shape and having a flat major surface”, please refer to pp. 7-9 of Applicant’s remarks, where the Applicant states that the prior art reference, Clarke, “has no shield electrode” or “no suggested casting material,…cannot teach connecting electrodes embedded in a casting material to make them operable as electrodes in a capacitor of a voltage divider”, and that prior art reference Moore, “electrodes are embedded in casting material and are not connected with anything outside, hence they cannot be used as electrodes in a voltage divider”. The Examiner appreciates the explanation and the evidence provided; however, it is noted that the claims are examined given the broadest reasonable interpretation. In the immediate case of this application, the Examiner has taken the interpretation that “a sensored bushing with spacers of “an annular spacer having a flat major surface” embedded in casting material and arranged between a sensing electrode and a shield electrode”, as disclosed by Moore, in view of Clarke, please refer to the Non-Final OA pp. 3-7.
This leads to the second part the Examiner would like to highlight, how the prior art reference, Moore, reads on the claims. The Examiner mapped the “a sensored bushing with spacers of “an annular spacer having a flat major surface” embedded in casting material and arranged between a sensing electrode and a shield electrode”, (Fig. 1; [Col. 2, ll. 50-67], [Col. 3, ll. 7-11, 19-24, 50-54 & 65-68], [Col. 4, ll. 1-5, 12-14 & 53-65], [Col. 5, ll. 43-45] & [Claim 1]), including the Non-Final OA pp. 3-7, where page 5 further discloses [Col. 1, ll. 12-30] & [Col. 3, ll. 19-31], noting that the use of spacers is well-known in the present field, and can be further modified, as needed, to be encased and arranged in casting material. Further stating “Encapsulating a capacitor structure into a cast epoxy electrical bushing has been accomplished…” and that “the cylindrical capacitor sections of the capacitor structure are held in place by a suitable arrangement, such as by a fixture located at the ends of the capacitor sections or by special spacers located between the ends of concentric capacitor sections”. Furthermore, page. 17 in the Non-Final OA further discloses [Col. 2, ll. 30-49], that mention “The capacitor structure 20, which includes the capacitor sections 22 and 24, embedded in the epoxy bushing insulator 14 as shown in Fig. 1.” Therefore the spacers in Moore, would have a flat surface due to the epoxy resin providing an overall rigid structure, that would in essence “encapsulate” the members, filling the voids, forming the “flat major surface”, and Figure 1 further depicts the mesh members (spacers 32 & 36). Moore further teaches the inner perimetral edge of spacer 50 contacts/connects to the inner mandrel, which forms the sensing electrode structure in ([Col. 3, ll. 7-11, 19-24, 50-54 & 65-68] & [Col. 4, ll. 1-5, 12-14 & 53-65]) and further teaches the outer perimetral edge of spacer 50 connects to mesh 60 and foil 62 (shield electrode) in ([Col. 3, ll. 7-11, 19-24, 50-54 & 65-68] & [Col. 4, ll. 1-5, 12-14, 23-26 & 53-65]). Moore’s design mentions the “cylindrical capacitor sections of the capacitor structure are held in place by suitable arrangement” in [Col. 1, ll. 22-27], and “provide separation at the top and bottom of the capacitor structure, suitable spacers, such as the spacers 28 taught by U.S. Pat. No. 3, 769, 447, may be used” in [Col. 4, ll. 53-65]. Further, modifying the capacitor (containing the electrode(s)) arrangement in Moore, referencing Quirk, to lead to the “casting material” with spaced capacitors, which contain the electrodes, where Moore/Quirk disclose the spacers 28 of Quirk, into Moore’s teachings, are mechanically connected between electrodes. Therefore, would be obvious to a POSITA that the arrangement of the capacitors is a matter of design choice/arrangement.
In regard to prior art reference, Clarke, as referenced by the Applicant, the reference further overcomes any deficiencies of Moore and/or Moore/Quirk, further disclosing/teaching using electrodes for sensing, specifically the shielding/guard/sensing function of the electrodes in ([Abstract], [Col. 1, ll. 6-11 & 51-62], [Col. 3, ll. 51-61], [Col. 4, ll. 49-64], [Col. 5, ll. 34-64], [Col. 15, ll. 24-34] & [Col. 16. ll. 9-12]). With prior art reference, Clarke, combined with the teachings of Moore, would lead a POSITA to combine the elements of Moore (e.g., casting material and capacitors), modifying Moore’s capacitors to be the “high voltage capacitor connected to earth through a low voltage capacitor, thus forming a capacitive voltage divider so that the voltage of the conductor may be determined”, of Clarke, in ([Col. 1, ll. 17-20]), providing the motivation to use the embedded primary capacitor specifically as a sensing voltage divider to monitor the line voltage, while Moore teaches the physical structure of a tubular electrode (foil capacitor section) embedded coaxially in the cast material in ([Col. 2, ll. 41-49]). Based on the reasoning provided above, the Examiner believes Moore/Quirk, in view of Clarke, teach the limitations recited in previously presented independent claim 1. Therefore, the rejection(s) independent claim 1, and dependent claims 2-13, which depend from and incorporate the limitations of independent claim 1, are respectively maintained.
In response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007).
In this case, Applicant in their submitted response presents the argument that the prior art references, Moore et al. (US3967051), in view of Clarke et al. (US4963819), to include the referenced prior art reference Quirk et al. (US3769447), and further in view of Ferraro et al. (US2021/0356499), do not teach, disclose, and/or suggest, individually, or in combination, the limitation “a first spacer, arranged radially between the sensing electrode and the shield electrode, and mechanically connected to the sensing electrode and to the shield electrode to maintain the sensing electrode and the shield electrode in a fixed spatial relation to each other, wherein the first spacer is of annular shape and comprises a flat major surface delimited radially by an outer perimetral edge and an inner perimetral edge,” recited in the previously presented independent claim 14.
The examiner respectfully disagrees and would like to break the argument presented into two sections. The first part the Examiner would like to highlight is in regard to the explanations provided above for independent claim 1, which has similar amended independent claim 14, please refer to pp. 7-14 of Applicant’s remarks, where the Applicant states that the prior art reference, Moore, discloses “spacers ‘28’ at col 4 lines 60-69 in the context of describing content of prior art (the Quirk ‘447 reference, for example)”, and that the “spacers in Quirk are not illustrated nor described as having a flat major surface”, instead “the spacer geometry is described as “dimples”, “insulating buttons or spacer sticks”. The Examiner appreciates the explanation and the evidence provided; however, it is noted that the claims are examined given the broadest reasonable interpretation. In the immediate case of this application, the Examiner has taken the interpretation that “an annular spacer having a flat major surface”, as disclosed by Moore, who further references Quirk in regard to these limitations, please refer to the Non-Final OA pp. 17-21.
This leads to the second part the Examiner would like to highlight, how the prior art reference, Moore, reads on the claims. The Examiner mapped the “wherein the first spacer is of annular shape and comprises a flat major surface delimited radially by an outer perimetral edge and an inner perimetral edge,” (Fig. 1; [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]), including the Non-Final OA pp. 7 & 17-21, where page 7 further discloses [Col. 3, ll. 12-18], mentioning an “overall tapered cylindrical, or conical shape, and the mesh members 28 and 30, are coated with an epoxy resin, where the “penetration by the epoxy…form a substantially voidless bond”, and further stating that the mesh members are “treated prior to encapsulation to make them rigid for the purpose of maintaining separation distances”. Therefore the spacers in Moore, would be modified to have a flat surface due to the epoxy resin providing an overall rigid structure, that would in essence “encapsulate” the members, filling the voids, forming the “flat major surface”, and Figure 1 further depicts the mesh members (spacers 32 & 36). Moore uses a tapered mesh because a solid flat surface would block the axial flow of the injected epoxy resin during the casting process, and defeating the manufacturing methodology. Further, modifying the spacer in Moore, in view of Quirk, to lead to the “annular shape and having a flat major surface” is a matter of design choice.
As referenced by prior art reference, Moore, in (Fig. 1; [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]: standard spacers 28 “taught by U.S. Pat. No. 3,769,447” incorporated by reference, which are included in Moore’s prior art reference, have an annular shape because it is symmetric as depicted in the section of Fig. 1, with flat major surfaces, where Moore discloses the alternative or supplementary use of the standard spacers at the top and bottom to ensure separation of the use of spacers is well-known in the present field). Quirk mentions that “any interfaces not eliminated will trap air which will induce the start of corona at high voltages” ([Col. 1, ll. 46-50]), and further discloses the shape and flat surface ([Col. 4, ll. 24-37]), where “all surfaces on the underside of the sheet tend to have a rounded effect will discourage the formation of corona on the underside of the sheet” and “it is seen that the top surface 30 of the material is flat and provides a good surface for applying the conductive elements…”. Combining the teachings of Quirk into Moore, would be obvious to a POSITA, that by implementing epoxy, as taught by Moore, and combining with Quirk’s teachings (e.g., annular shape because they extend around the conductor and appear symmetric in a section of the bushing in Fig. 1 and flat surface), the combination would result in a spacer with an annular shape comprising a flat major surface without “dimples” or “insulating buttons or spacer sticks”.
In regard to prior art reference, Clarke, as referenced by the Applicant, the reference further overcomes any deficiencies of Moore and/or Moore/Quirk, further stating that it utilizes “conductive polymeric CNTM tubings 20…forming guard rings…clamping…two aluminum half-shells to form a housing 30 that seals at each end…” in ([Col. 1, ll. 31-34 & 51-67], [Col. 2, ll. 49-64], [Col. 9, ll. 18-62] & [Col. 14, ll. 3-14]). If Clarke were to be incorporated into the combination of references, again would lead a POSITA to a design choice, and would be obvious to modify the spacers, interpreted as the guard rings, to have the “annular shape and having a flat major surface.”
In regard to prior art reference, Ferraro, further supplements the combination of Moore/Quirk/Clarke, further teaching and disclosing dual concentric tubular electrodes (sensing and shield) and the use of an annular spacer placed (“O-ring”) radially between the inner and outer electrodes to mechanically connect and maintain their fixed spatial relation prior to the casting process in (Fig. 4; [0037], [0046] & [0049]). Ferraro uses “O-rings” and these could be modified into a flat-washer-like ring to provide a “flat major surface” or substituting with a flat annular washer or flat gasket or other known mechanical equivalent to provide a stable seating surface against the tubular electrodes. Based on the reasoning provided above, the Examiner believes Moore/Quirk, in view of Clarke, and further in view of Ferraro, teach the limitations recited in amended independent claim 14 as presented. Therefore, the rejection(s) of amended independent claim 14, which currently doesn’t have any dependent claims, are respectively maintained.
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 1-14 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.
Claim 1 recites the limitation “the length direction of the bushing conductor” in line 7, without previous disclosure, resulting in a lack of antecedent basis for this limitation in the claim. For examination purposes, the examiner interprets this limitation to read as “a length direction of the bushing conductor”. Claims 2-11 are rejected by virtue of dependance to independent claim 1, which do not rectify the defect(s).
Claim 8 recites the limitation "the change in resistance" in line 3, without previous disclosure, resulting in a lack of antecedent basis for this limitation in the claim. For examination purposes, the examiner interprets this limitation to read as “a change in resistance”. Claim 9 is rejected by virtue of dependance to dependent claim 8, which does not rectify the defect(s).
Claim 13 recites the limitation “Power distribution network of a national grid for distributing electrical power at medium or high voltages” in ll. 1-2, which was previously disclosed in claim 12. The repeated recitation of “Power distribution network of a national grid…”, introduces indefiniteness, for the limitations in the claim. For examination purposes, examiner interprets this limitation to read as “The Power distribution network of the national grid for distributing the electrical power at medium or high voltages,”.
Claim 14 recites the limitation “the length direction of the bushing conductor” in line 7, without previous disclosure, resulting in a lack of antecedent basis for this limitation in the claim. For examination purposes, the examiner interprets this limitation to read as “a length direction of the bushing conductor”.
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.
Claims 1, 4, & 6 are rejected under 35 U.S.C. 103 as being unpatentable over Moore et al. (US3967051, Pub. Date Jun. 29, 1976, hereinafter Moore), in view of Clarke et al. (US4963819, Pat. Date Oct. 16, 1990, hereinafter Clarke).
Regarding independent claim 1, Moore, teaches:
Sensored bushing for connecting a separable connector to a switchgear or to a transformer in a power distribution network of a national grid for distributing electrical power at medium or high voltages, the bushing comprising (Fig. 1; [Col. 1, ll. 8-10] & [Col. 2, ll. 35-40])
a bushing body comprising a solidified, electrically insulating casting material ([Col. 1, 12-30 & 47-66], [Col. 2, ll. 35-40], [Col. 5, ll. 32-35] & [Col. 6, ll. 17-19]: discloses a bushing body made of cast epoxy and aims solving the traditional use of spacers at the end of a capacitor section embedded into a solidified cast epoxy structure);
b) an elongated bushing conductor, embedded in the casting material, for conducting power at an elevated voltage and at currents of ten Ampere or more into the switchgear or the transformer, the length direction of the bushing conductor defining a bushing axis and axial directions and radial directions orthogonal to the bushing axis (Fig. 1; [Col. 2, ll. 30-49], [Col. 5, ll. 1-7 & 32-35], [Col. 6, ll. 17-19], [Claim 1], [Claim 6] & [Claim 7]: conductor 12; discloses a central conductor stud embedded in the epoxy resin material and carries power current, electrical conductors in HV/MV apparatus necessarily conduct currents of 10 Ampere or more);
c) a tubular sensing electrode, embedded in the casting material and arranged coaxially around the bushing conductor (Fig. 1; [Col. 2, ll. 30-54] & [Col. 5, ll. 36-41]: capacitor sections 22 and 24, discloses tubular sections (electrodes) embedded in the epoxy resin material),
d) a tubular shield electrode, embedded in the casting material, arranged coaxially around the sensing electrode ([Col. 2, ll. 41-54]: discloses multiple concentric capacitor foils (electrodes) separated by insulation, one foil acts as the sensing electrode, the concentric outer foil acts as the shield/guard electrode),
e) a first spacer, embedded in the casting material and arranged radially between the sensing electrode and the shield electrode (Fig. 1; [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]: spacers 32 and 36, discloses using spacers at the ends of the electrodes to maintain separation (fixed spatial relation)),
wherein the first spacer is mechanically connected to the sensing electrode and to the shield electrode to maintain the sensing electrode and the shield electrode in a fixed spatial relation to each other, wherein the first spacer is of annular shape and comprises a flat major surface delimited radially by an outer perimetral edge and an inner perimetral edge (Fig. 1; [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]: discloses using spacers at the ends of the electrodes to maintain separation (fixed spatial relation), standard spacers “taught by U.S. Pat. No. 3,769,447” incorporated by reference are annular with flat major surfaces, Moore discloses the alternative or supplementary use of the standard spacers at the top and bottom to ensure separation the use of spacers is well-known in the present field),
wherein the first spacer is mechanically connected to the sensing electrode at the inner perimetral edge, and wherein the first spacer is mechanically connected to the shield electrode at the outer perimetral edge (Fig. 1; [Col. 1, ll. 12-30], [Col. 3, ll. 19-31], [Col. 4, ll. 62-65], & [Col. 5, ll. 43-45]).
Moore, is silent in regard to:
c) wherein the sensing electrode and the bushing conductor are operable as electrodes of a primary capacitor, a dielectric of the primary capacitor being formed by a first portion of the casting material arranged between the sensing electrode and the bushing conductor, wherein the primary capacitor is operable as a high-voltage capacitor in a high-voltage portion of a sensing voltage divider for sensing the elevated voltage of the bushing conductor;
d) and insulated against the sensing electrode by a second portion of the casting material arranged between the sensing electrode and the shield electrode;
However, Clarke, further teaches:
c) wherein the sensing electrode and the bushing conductor are operable as electrodes of a primary capacitor, a dielectric of the primary capacitor being formed by a first portion of the casting material arranged between the sensing electrode and the bushing conductor, wherein the primary capacitor is operable as a high-voltage capacitor in a high-voltage portion of a sensing voltage divider for sensing the elevated voltage of the bushing conductor ([Col. 1, ll. 6-11 & 51-62] & [Col. 15, ll. 24-34]: teaches using such electrodes for sensing);
d) and insulated against the sensing electrode by a second portion of the casting material arranged between the sensing electrode and the shield electrode ([Abstract], [Col. 3, ll. 51-61], & [Col. 16, ll. 9-12]: teaches the shielding/guard function);
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the sensing electrode and the bushing conductor are operable as electrodes of a primary capacitor, a dielectric of the primary capacitor being formed by a first portion of the casting material arranged between the sensing electrode and the bushing conductor, wherein the primary capacitor is operable as a high-voltage capacitor in a high-voltage portion of a sensing voltage divider for sensing the elevated voltage of the bushing conductor and insulated against the sensing electrode by a second portion of the casting material arranged between the sensing electrode and the shield electrode, of Clarke to Moore, according to known methods. Where Moore discloses a cast resin bushing with a central conductor, embedded concentric capacitor electrodes for stress distribution, and spacers that maintain fixed distances between those electrodes. Clarke discloses a high-voltage sensing apparatus utilizing a capacitor structure for the purpose of voltage sensing (a sensing bushing) in power distribution networks, where a coaxial sensing electrode and a grounded shield/guard ring electrode are used to accurately measure voltage on a power distribution conductor. In order to improve by adapting the known capacitor bushing structure of Moore to include the voltage-sensing functionality of Clarke, recognizing the outer capacitor foil in Moore as the sensing electrode and grounding as an outermost conductive layer to function as the shield electrode, to provide a bushing that not only handles electrical stress but can also provide voltage monitoring capabilities (“Sensored bushing”) necessary for modern grid automation, and would be obvious to apply to ensure the reliability and accuracy of Clarke’s sensing arrangement, arriving at the claimed invention with predictable results (KSR).
Regarding dependent claim 4, Moore, teaches:
Sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]), wherein the first spacer comprises one or more apertures for allowing liquid casting material to flow from one side of the first spacer through the one or more apertures to the opposite side of the first spacer ([Col. 2, ll. 54-62] & [Col. 3, ll. 12-18]: discloses spacers made of “non-conductive mesh” designed to allow resin flow, the flow prevents voids by allowing the material to move from one side of the mesh spacer to the other, creating a solid bond).
Regarding dependent claim 6, Moore, teaches:
Sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]), further comprising a second spacer, embedded in the casting material and arranged radially between the sensing electrode and the shield electrode (Fig. 1; [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]: discloses the use of spacers at multiple locations (top and bottom) to separate concentric capacitor sections (electrodes), where the spacer at the top and the spacer at the bottom constitute a first and second spacer),
wherein the second spacer is mechanically connected to the sensing electrode and to the shield electrode to maintain the sensing electrode and the shield electrode in a fixed spatial relation to each other (Fig. 1; [Col. 3, ll. 19-31], [Col. 4, ll. 53-65] & [Col. 5, ll. 43-45]: states the purpose is to maintain separation (fixed spatial relation)).
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Moore, in view of Clarke, and further in view of Quirk et al. (US 3769447, Pub. Date Oct. 30, 1973, hereinafter Quirk).
Regarding dependent claim 2, Moore, teaches:
Sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40], & [Col. 4, ll. 62-65]: teaches the location of the spacers at the axial ends (top and bottom)),
Moore, and Clarke, are silent in regard to:
wherein the first spacer is oriented such that a normal on the major surface is oriented parallel to a central axis of the tubular sensing electrode or to a central axis of the tubular shield electrode.
However, Quirk, further teaches:
wherein the first spacer is oriented such that a normal on the major surface is oriented parallel to a central axis of the tubular sensing electrode or to a central axis of the tubular shield electrode (Figs. 1 & 2; [Col. 4, ll. 6-16]: teaches the function of the spacers of various types, the spacer can be implemented as a spacer stick that is a radial element with its major surface having a normal oriented parallel to the central axis of the tubular sensing electrode).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the first spacer is oriented such that a normal on the major surface is oriented parallel to a central axis of the tubular sensing electrode or to a central axis of the tubular shield electrode, of Quirk, to Moore and Clarke, according to known methods. Where Moore discloses the primary structure, a cast resin bushing with a central conductor, embedded concentric capacitor electrodes for stress distribution, and discusses the need for maintaining radial separation between the electrodes during the casting process to prevent distortion with spacers that maintain fixed distances between those electrodes. Clarke discloses a high-voltage sensing apparatus utilizing a capacitor structure for the purpose of voltage sensing (a sensing bushing) in power distribution networks. While Quirk provides specific details of the spacer element, Moore further teaches placing the spacers at the “top and bottom” of the capacitor structure, Quirk further teaches the spacers maintain concentric radial spacing, and would be obvious to orient a spacer located at the “top” or “bottom” (axial ends) of a concentric tubular assembly such that it lies flat with the radial-cross section (a “washer” orientation) or using a stick which is a radial element with its major surface having a normal oriented parallel to the central axis of the tubular sensing electrode. Where in a standard mechanical orientation, the flat major surface of the spacer is perpendicular to the bushing axis, meaning the normal to that surface is parallel to the axis as claimed, thus yielding expected predictable results (KSR).
Claims 3, 7, 10-11 & 14 are rejected under 35 U.S.C. 103 as being unpatentable over Moore, in view of Clarke, and further in view of Ferraro et al. (US 2021/0356499 A1, Fil. Date May. 06, 2021, hereinafter Ferraro).
Regarding dependent claim 3, Moore, teaches:
Sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]),
Moore, and Clarke, are silent in regard to:
wherein the first spacer comprises, on the major surface, a first conductive trace and a second conductive trace for respective electrical connection of electric or electronic components mounted on the first spacer, and wherein the inner perimetral edge comprises a conductive portion, said conductive portion being conductively connected with the first conductive trace and conductively connected with the sensing electrode,
and optionally wherein the outer perimetral edge comprises a conductive portion, said conductive portion being conductively connected with the second conductive trace and conductively connected with the shield electrode.
However, Ferraro, further teaches:
wherein the first spacer comprises, on the major surface, a first conductive trace and a second conductive trace for respective electrical connection of electric or electronic components mounted on the first spacer ([0037]-[0038]: teaches using a PCB ( which is a rigid spacer with a flat surface containing conductive traces) as a spacer/mount between electrodes), and wherein the inner perimetral edge comprises a conductive portion, said conductive portion being conductively connected with the first conductive trace and conductively connected with the sensing electrode ([0037]-[0038]: teaches the electrical connection at the inner aspect of the PCB spacer to the sensing electrode, solder joint 111 and associated via/pad at the connection point constitutes the conductive portion at the edge or connection point, linking the trace (to capacitors 112/114) with the sensing electrode 106),
and optionally wherein the outer perimetral edge comprises a conductive portion, said conductive portion being conductively connected with the second conductive trace and conductively connected with the shield electrode ([0037]-[0038]: teaches the connection to the outer shield electrode, where the PCB (spacer) is mechanically and electrically mounted to the outer sensor electrode 108 (acting as the shield/reference) via fastener 113 at its outer position, where the fastener/mount serves as the conductive portion at the “outer perimetral edge” connecting the PCB traces to the shield electrode 108).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the first spacer comprises, on the major surface, a first conductive trace and a second conductive trace for respective electrical connection of electric or electronic components mounted on the first spacer, and wherein the inner perimetral edge comprises a conductive portion, said conductive portion being conductively connected with the first conductive trace and conductively connected with the sensing electrode, and optionally wherein the outer perimetral edge comprises a conductive portion, said conductive portion being conductively connected with the second conductive trace and conductively connected with the shield electrode, of Ferraro, to Moore and Clarke, according to known methods. Where Moore discloses the primary structure, a cast resin bushing with a central conductor, embedded concentric capacitor electrodes and spacers to maintain electrode separation and provide mechanical support. Clarke teaches the “sensored” aspect using the capacitor structure for voltage sensing in a power distribution network with the sensing circuitry connected to the electrodes. Ferraro teaches the implementation of the spacer as a component carrier (PCB) with conductive traces, integrating the sensing components and electrical connections within a bushing, teaching the use of a spacer in the form of a PCB mounted between electrodes. The PCB includes conductive traces for connecting components like capacitors and uses conductive portions at its edges (solder joints, inner/outer conductors) to electrically connect to the respective sensor and shield electrodes. Therefore, would be obvious to replace or improve the mechanical spacers of Moore with the PCB spacers of Ferraro to facilitate the electrical connections required by Clarke’s sensing signals, achieving a compact, integrated “sensored bushing”, and yield expected predictable results (KSR).
Regarding dependent claim 7, Moore, teaches:
Sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]), further comprising
Moore, and Clarke, are silent in regard to:
a correction contact, accessible from outside the sensored bushing; and
a correction resistor having a temperature-dependent electrical resistance for providing, at the correction contact, a correction signal which varies with a temperature of the casting material,
wherein the correction resistor
- is arranged in the bushing body;
- is thermally connected to the casting material; and
- is electrically connected to the correction contact.
However, Ferraro, further teaches:
a) correction contact, accessible from outside the sensored bushing ([0003], [0015], [0042]-[0043] & [Claim 13]: teaches a connector (contact) electrically connected to the sensor and accessible externally); and
b) a correction resistor having a temperature-dependent electrical resistance ([0015], [0042]-[0043] & [Claim 13]: teaches a temperature sensor used for compensation, a thermistor is a well-known resistor having a temperature-dependent electrical resistance) for providing, at the correction contact, a correction signal which varies with a temperature of the casting material ([0042]-[0043]: teaches using the temperature signal for correction),
wherein the correction resistor
- is arranged in the bushing body ([0015],[0042]-[0043] & [Claim 13]: requires the sensor to be embedded);
- is thermally connected to the casting material ([0003], [0008], [0015], [0042]-[0043], [Claim 13] & [Claim 14]: thermistor (correction resistor) is embedded in the electrically insulating body (casting material e.g., epoxy resin), allowing it to sense the material’s temperature); and
- is electrically connected to the correction contact ([0003], [0015], [0042]-[0043] & [Claim 13]).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate a correction contact, accessible from outside the sensored bushing; and a correction resistor having a temperature-dependent electrical resistance for providing, at the correction contact, a correction signal which varies with a temperature of the casting material, wherein the correction resistor is arranged in the bushing body; is thermally connected to the casting material; and is electrically connected to the correction contact, of Ferraro, to Moore and Clarke, according to known methods. Where Moore and Clarke together establish the art of a cast resin capacitor bushing used for voltage measurement (“sensored bushing”). Moore discloses the cast resin bushing structure embedded with electrodes, and Clarke discloses using this structure for high-voltage sensing. Ferraro teaches a modern capacitive voltage sensor where a concern is the accuracy of the measurement being affected by temperature-dependent changes in the permittivity of the casting material (epoxy resin). Therefore, would be obvious to incorporate the known temperature compensation mechanism of Ferraro into the existing sensored bushing of Moore/Clarke, to improve the accuracy and reliability of the voltage measurement by monitoring temperature of the bushing’s insulating material and providing a correction signal for external compensation, and yield expected predictable results (KSR).
Regarding dependent claim 10, Moore, teaches:
Sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]),
Moore, and Clarke, are silent in regard to:
wherein the sensing electrode comprises a mesh of conductive wires forming apertures between them.
However, Ferraro, further teaches:
wherein the sensing electrode comprises a mesh of conductive wires forming apertures between them ([0037], [0040]-[0041] & [0047]: discloses forming the sensing electrode as a mesh).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the sensing electrode comprises a mesh of conductive wires forming apertures between them, of Ferraro, to Moore and Clarke, according to known methods. Where Moore and Clarke together establish the art of a cast resin bushing containing capacitor electrodes for voltage sensing (“sensored bushing”). Moore discloses the cast resin bushing structure embedded with capacitor sections, and Clarke teaches using this structure for measuring voltage in power distribution networks. Ferraro teaches a structural modification of the sensing electrode, forming the sensing electrodes with an open mesh or screen structure, to “improve the bushing reliability as well as fabrication yield” by permitting “free-flow of the material (e.g., epoxy resin)…thereby facilitating conformal coverage”. Therefore, would be obvious to replace the solid foil sensing electrode of Moore/Clarke with the conductive mesh sensing electrode taught by Ferraro to achieve better resin permeation and reduce voids during the casting process, and yield expected predictable results (KSR).
Regarding dependent claim 11, Moore, teaches:
Sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]), further comprising
Moore, and Clarke, are silent in regard to:
a) a signal contact, conductively connected to the sensing electrode and arranged on an outer surface of the bushing body,
and optionally
a grounding contact (340), conductively connected to the shield electrode and arranged on an outer surface of the bushing body.
However, Ferraro, further teaches:
a) a signal contact, conductively connected to the sensing electrode and arranged on an outer surface of the bushing body ([0037] & [Claim 1]: discloses a signal contact (connector 107) connected to the sensing electrode 106 and exposed on the surface),
and optionally
a grounding contact (340), conductively connected to the shield electrode and arranged on an outer surface of the bushing body ([0037]-[0038] & [Claim 1]: discloses a contact (connector 109) connected to the shield electrode 108 and exposed on the surface).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate a) a signal contact, conductively connected to the sensing electrode and arranged on an outer surface of the bushing body, and optionally b) a grounding contact, conductively connected to the shield electrode and arranged on an outer surface of the bushing body, of Ferraro, to Moore and Clarke, according to known methods. Where Moore and Clarke together establish the art of a cast resin bushing containing embedded capacitor electrodes for voltage measurement. Moore discloses the cast resin bushing structure embedded with capacitor sections, and Clarke teaches using this structure for measuring voltage in power distribution networks. Ferraro teaches the mechanical interface for accessing the electrical signals generated by the embedded electrodes, integrating these connections as contacts or connectors arranged on the outer surface of the bushing body. Therefore, would have been obvious for a POSITA to implement the connections of Moore/Clarke using the surface-mounted connectors of Ferraro to provide an improved robust, accessible, and standardized interface for connecting external monitoring equipment (determining voltage presence or metering) to embedded sensors, and yield expected predictable results (KSR).
Regarding independent claim 14, Moore, teaches:
Process of manufacturing a sensored bushing ([Claim 7])
the sensored bushing comprising
a) a bushing body ([Col. 1, ll. 47-50]);
b) an elongated bushing conductor, embedded in the bushing body, for conducting power at currents of ten Ampere or more, the length direction of the bushing conductor defining axial directions and radial directions orthogonal to the axial directions (Fig. 1; [Col. 2, ll. 30-49], [Col. 5, ll. 1-7 & 32-35], [Col. 6, ll. 17-19], [Claim 1], [Claim 6] & [Claim 7]: conductor is elongated and carries power current, electrical conductors in HV/MV apparatus necessarily conduct currents of 10 Ampere or more); and
c) an electrode assembly embedded in the bushing body, arranged coaxially around the bushing conductor and comprising (Fig. 1; [Col. 2, ll. 30-54] & [Col. 5, ll. 36-41]: capacitor sections 22 and 24, discloses tubular sections (electrodes) embedded in the epoxy resin material)
ii) a tubular shield electrode, arranged coaxially around the sensing
electrode ([Col. 2, ll. 41-54]),
iii) a first spacer, arranged radially between the sensing electrode and the shield electrode (Fig. 1; [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]), and mechanically connected to the sensing electrode and to the shield electrode to maintain the sensing electrode and the shield electrode in a fixed spatial relation to each other, wherein the first spacer is of annular shape and comprises a flat major surface delimited radially by an outer perimetral edge and an inner perimetral edge (Fig. 1; [Col. 1, ll. 31-39], [Col. 3, ll. 19-24], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]: discloses using spacers at the ends of the electrodes to maintain separation (fixed spatial relation), standard spacers “taught by U.S. Pat. No. 3,769,447” incorporated by reference are annular with flat major surfaces, Moore discloses the alternative or supplementary use of the standard spacers at the top and bottom to ensure separation the use of spacers is well-known in the present field),
wherein the first spacer is mechanically connected to the sensing electrode at the inner perimetral edge, and wherein the first spacer is mechanically connected to the shield electrode at the outer perimetral edge (Fig. 1; [Col. 1, ll. 12-30], [Col. 3, ll. 19-31], [Col. 4, ll. 62-65] & [Col. 5, ll. 43-45]);
wherein the process comprises
- arranging the electrode assembly such that the sensing electrode is arranged coaxially around the bushing conductor, and previously or subsequently (Fig. 1; [Col. 2, ll. 41-62] & [Claim 7]: teaches arranging the concentric electrode assembly coaxially around the conductor) arranging the bushing conductor and the electrode assembly in a mold ([Col. 1, 12-30 & 47-66], [Col. 2, ll. 35-40], [Col. 5, ll. 32-35], [Col. 6, ll. 17-19] & [Claim 7]);
- filling the mold with a liquid, electrically insulating, solidifiable casting material such that the bushing conductor and the electrode assembly are embedded in the casting material and such that portions of the casting material are arranged between the bushing conductor and the sensing electrode and between the sensing electrode and the shield electrode and embeds them ([Col. 1, 8-39 & 47-66], [Col. 2, ll. 35-62], [Col. 5, ll. 32-35], [Col. 6, ll. 17-19], [Claim 1], [Claim 5, ][Claim 6] & [Claim 7]: epoxy resin is a liquid, electrically insulating, solidifiable casting material, by its natures in a casting process, the resin is arranged between the coaxial components (conductor, sensing electrode, shield electrode);
- solidifying the casting material to form the bushing body such that the bushing conductor and the electrode assembly are embedded in the casting material ([Col. 1, 8-39 & 47-66], [Col. 2, ll. 35-62], [Col. 5, ll. 32-35], [Col. 6, ll. 17-19], [Claim 1], [Claim 5], [Claim 6] & [Claim 7]).
Moore, is silent in regard to:
for connecting a separable connector to a switchgear or to a transformer in a power distribution network of a national grid for distributing electrical power at medium or high voltages,
a tubular sensing electrode,
However, Ferraro, further teaches:
for connecting a separable connector to a switchgear or to a transformer in a power distribution network of a national grid for distributing electrical power at medium or high voltages ([0001]-[0004], [0034]-[0035], [0045], [0057], [0059] & [0061]),
a tubular sensing electrode (Fig. 1B; [Abstract]: discloses a tubular/cylindrical electrode),
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate for connecting a separable connector to a switchgear or to a transformer in a power distribution network of a national grid for distributing electrical power at medium or high voltages, and a tubular sensing electrode, of Ferraro, to Moore and Clarke, according to known methods. Where Moore and Clarke together establish the art of a cast resin bushing with embedded capacitor electrodes for voltage measurement. Moore teaches embedding coaxial conductive elements and spacers in a mold using epoxy resin. Clarke and Ferraro teach known capacitive sensor/bushing structures of high voltage or medium voltage applications, specifically using sensing and shielding electrodes. Clarke and Ferraro further teach the environment in which these devices operate: a power distribution network (often part of a national grid). Where Clarke describes mounting the apparatus on overhead lines of a “24 kV power distribution system,” Ferraro describes the need for such sensors in the ”Smart Grid” and “electrical power distribution network”. Therefore, it would have been obvious to a POSITA that the electrical apparatus (switchgear/transformer) containing the sensored bushing is a constituent part of the larger power distribution network described by Clarke and Ferraro. The fundamental purpose of the bushing is to improve and facilitate the distribution and monitoring of power within that power grid. Therefore, combining the known sensor electrode structure of Ferraro/Clarke with the established, cast-resin manufacturing process of Moore, would improve and produce a rugged, encapsulated, high-dielectric sensored bushing, a common goal in the field of power distribution equipment, and yield expected predictable results (KSR).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Moore, in view of Clarke, and further in view of Gravermann et al. (US 2017/0234908 A1, Pub. Date Aug. 17, 2017, hereinafter Gravermann).
Regarding dependent claim 5, Moore, teaches:
Sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]),
Moore, and Clarke, are silent in regard to:
wherein the first spacer is, or comprises, a printed circuit board wherein the sensored bushing further comprises a low-voltage capacitor conductively connected with the sensing electrode and mounted on the printed circuit board, wherein the low-voltage capacitor is comprised in a low-voltage portion of the sensing voltage divider for sensing the elevated voltage of the bushing conductor, and wherein the primary capacitor is comprised in a high-voltage portion of the sensing voltage divider.
However, Gravermann, further teaches:
wherein the first spacer is, or comprises, a printed circuit board (Figs. 3 & 5; [0066] & [0074]: teaches providing a PCB associated with the electrode structure and electronic functionality) wherein the sensored bushing further comprises a low-voltage capacitor conductively connected with the sensing electrode and mounted on the printed circuit board ([0066-[0069]]: discloses the low-voltage capacitor on the PCB connected to the electrode), wherein the low-voltage capacitor is comprised in a low-voltage portion of the sensing voltage divider for sensing the elevated voltage of the bushing conductor ([0066]-[0069]: teaches the voltage function divider), and wherein the primary capacitor is comprised in a high-voltage portion of the sensing voltage divider ([0008]-[0009], [0066]-[0068] & [0077]: discloses the high-voltage capacitor structure).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the first spacer is, or comprises, a printed circuit board wherein the sensored bushing further comprises a low-voltage capacitor conductively connected with the sensing electrode and mounted on the printed circuit board, wherein the low-voltage capacitor is comprised in a low-voltage portion of the sensing voltage divider for sensing the elevated voltage of the bushing conductor, and wherein the primary capacitor is comprised in a high-voltage portion of the sensing voltage divider, of Gravermann, to Moore and Clarke, according to known methods. Where Moore discloses the primary bushing structure with embedded capacitor sections and spacers to maintain electrode geometry. Clarke provides the motivation to use this structure for voltage sensing (“sensored bushing”) by forming a capacitive voltage divider. Gravermann provides the implementation of sensing electronics, teaching the mounting of the low-voltage capacitor (secondary capacitor) on a PCB, further teaching arranging the PCB in direct contact with or close to the sensing electrode to establish the necessary electrical connection. Therefore, it would be obvious to modify the bushing of Moore/Clarke to include the PCB structure of Gravermann, integrating it with the spacer element, to provide a robust mounting platform for the low-voltage capacitor required for sensing, ensuring accurate positioning and reliable electrical connections within the compact bushing, and yield expected predictable results (KSR).
Claims 8 & 9 are rejected under 35 U.S.C. 103 as being unpatentable over Moore, in view of Clarke, in view of Ferraro, and further in view of Gravermann.
Regarding dependent claim 8, Moore, teaches:
Sensored bushing according to claim 7 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]),
Moore, and Clarke, are silent in regard to:
wherein the correction resistor has a relative resistance temperature dependency of ∆R/R0 > 1 x 10-4 per degree Celsius,
However, Ferraro, further teaches:
wherein the correction resistor has a relative resistance temperature dependency of ∆R/R0 > 1 x 10-4 per degree Celsius ([0003], [0015], [0042]-[0043] & [Claim 13]: teaches using a thermistor as the correction resistor, a thermistor is a resistor whose resistance changes significantly with temperature),
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the correction resistor has a relative resistance temperature dependency of ∆R/R0 > 1 x 10-4 per degree Celsius, of Ferraro, to Moore and Clarke, according to known methods. Where Moore and Clarke together establish the art of a cast resin capacitor bushing used for voltage sensing in power distribution networks. Ferraro teaches incorporating a correction resistor (thermistor) into the bushing to measure temperature and provide a correction signal (solution), further teaches using a thermistor for temperature sensing, which is a resistor designed to have a large temperature coefficient of resistance (TCR) to maximize sensing sensitivity. It is well-known in the art/field that standard thermistors exhibit resistance changes in the range of 3% to 5% per degree Celsius (3 x 10-2 to 5 x 10-2). The claimed value of 1 x 10-4 (0.01%) is a low threshold that is met by a standard resistor (thermistor) chosen for the purpose of sensing as taught by Ferraro. Therefore, would be obvious to a POSITA to select a standard thermistor with a TCR within the standard commercial range, which is > 1 x10-4 to ensure the correction signal is strong enough for accuracy and reliability of the voltage measurement by monitoring temperature of the bushing’s insulating material and providing a correction signal for external compensation, thus yielding expected predictable results (KSR).
Moore, Clarke, and Ferraro, are silent in regard to:
where ∆R is the change in resistance between 0°C and 100°C, and R0 is the resistance at 0°C.
However, Gravermann, further teaches:
where ∆R is the change in resistance between 0°C and 100°C, and R0 is the resistance at 0°C ([0013]-[0014]: provides motivation for high-precision correction).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the correction resistor has a relative resistance temperature dependency of ∆R/R0 > 1 x 10-4 per degree Celsius, of Gravermann, to Moore, Clarke, and Ferraro, according to known methods. Where Moore and Clarke together establish the art of a cast resin capacitor bushing used for voltage sensing in power distribution networks. Ferraro teaches incorporating a correction resistor (thermistor) into the bushing to measure temperature and provide a correction signal (solution). Gravermann demonstrates that the accuracy of capacitive sensors is negatively affected by temperature changes due to temperature dependency of the dielectric material’s permittivity. Ferraro further teaches using a thermistor for temperature sensing, which is a resistor designed to have a large temperature coefficient of resistance (TCR) to maximize sensing sensitivity, where TCR (α) is defined as R-R0/R0(T-T0). Selecting a standard thermistor as taught by Ferraro, relies on this physical property to function as a temperature sensor, and it is well-known in the art/field that standard thermistors exhibit resistance changes in the range of 3% to 5% per degree Celsius (3 x 10-2 to 5 x 10-2). The claimed value of 1 x 10-4 (0.01%) is a low threshold that is met by a standard resistor (thermistor) chosen for the purpose of sensing as taught by Ferraro. Therefore, it would be obvious to a POSITA to select a standard thermistor with a TCR within the standard commercial range, which is > 1 x10-4 to ensure the correction signal is strong enough for accuracy and reliability of the voltage measurement by monitoring temperature of the bushing’s insulating material and providing a correction signal for external compensation, and yield expected predictable results (KSR).
Regarding dependent claim 9, Moore, teaches:
Sensored bushing according to claim 7 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65])
Moore, and Clarke, are silent in regard to:
wherein the correction resistor is arranged on the first spacer.
However, Ferraro, further teaches:
wherein the correction resistor is arranged on the first spacer ([0003], [0015] & [0042]-[0043]: teaches mounting the correction resistor (thermistor) on a carrier (PCB) located at the electrode).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the correction resistor is arranged on the first spacer, of Ferraro, to Moore and Clarke, according to known methods. Where Moore and Clarke together establish the art of a cast resin bushing with embedded capacitor electrodes used for voltage sensing in power distribution networks. Moore teaches the use of spacers (mesh or end spacers) to maintain the radial separation of these electrodes during casting, the spacers would provide mechanical support. Ferraro teaches implanting the temperature correction circuitry, disclosing a correction resistor (thermistor 202) to sense the temperature of the bushing material. Mounting this resistor on a PCB 204 that is physically mounted onto the sensor electrode within the bushing body, the PCB provides component support. Therefore, it would have been obvious to utilize the spacer of Moore or the PCB of Ferraro acting as a spacer and the physical mounting platform for the correction resistor. Combining these functions from both prior art references, using the spacer itself (e.g., a rigid PCB spacer) to carry the correction resistor directly onto the electrode structure where a spacer, such as Moore’s description, would be located or integrated, thus yielding expected predictable results (KSR).
Claims 12-13 are rejected under 35 U.S.C. 103 as being unpatentable over Moore, in view of Clarke, in view of Ferraro, and further in view of Potter et al. (US 2001/0048308 A1, Pub. Date Dec. 06, 2001, hereinafter Potter).
Regarding dependent claim 12, Moore, teaches:
b) a sensored bushing according to claim 1 (Fig. 1; [Col. 1, ll. 8-10], [Col. 2, ll. 35-40] & [Col. 4, ll. 62-65]),
Moore, and Clarke, are silent in regard to:
Electrical apparatus, such as a switchgear or a transformer, in a power distribution network of a national grid for distributing electrical power at medium or high voltages, the apparatus comprising
However, Ferraro, further teaches:
Electrical apparatus, such as a switchgear or a transformer, in a power distribution network of a national grid for distributing electrical power at medium or high voltages ([0001]-[0002]), the apparatus comprising
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate an Electrical apparatus, such as a switchgear or a transformer, in a power distribution network of a national grid for distributing electrical power at medium or high voltages, of Ferraro, to Moore and Clarke, according to known methods. Where Moore and Clarke together establish the art of a cast resin bushing with embedded capacitor electrodes for voltage measurement. Ferraro teaches the integration of such sensors into switchgear or transformers and connecting them to busbars. Therefore, it would be obvious to a POSITA to utilize the sensored bushing of Moore/Clarke in the switchgear apparatus taught by Ferraro, attaining the combination, a standard application of voltage sensors, monitoring the high-current power conductors (bus bars or cable conductors) within grid distribution equipment, and yield expected predictable results (KSR).
Moore, and Clarke, and Ferraro, are silent in regard to:
a) a power conductor, such as a bus bar or a central conductor of a power cable, in the apparatus for conducting the electrical power at currents of ten Ampere or more, and
wherein the power conductor is electrically connected to the bushing conductor.
However, Potter, further teaches:
a) a power conductor, such as a bus bar or a central conductor of a power cable, in the apparatus ([0022]-[0023] & [Claim 1]) for conducting the electrical power at currents of ten Ampere or more ([0005] & [0024]: discloses high current ratings well above 10 Amperes), and
wherein the power conductor is electrically connected to the bushing conductor ([Abstract] & [0022]-[0023]: discloses the electrical connection).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate a power conductor, such as a bus bar or a central conductor of a power cable, in the apparatus for conducting the electrical power at currents of ten Ampere or more, of Potter, to Moore, Clarke, and Ferraro, according to known methods. Where Moore and Clarke together establish the art of a cast resin bushing with embedded capacitor electrodes for voltage measurement. Ferraro teaches the integration of such sensors into switchgear or transformers and connecting them to busbars. Potter teaches the high-current capabilities and standard apparatus configurations required by the claim, disclosing a “voltage sensing bushing” designed for “600 ampere” applications and describes affixing the device directly to a “switchgear tank”. Therefore, it would be obvious to a POSITA to utilize the sensored bushing of Moore/Clarke/Ferraro, in the high-current switchgear apparatus taught by Potter, attaining the combination, which is a standard application of voltage sensors, monitoring the high-current power conductors (bus bars or cable conductors) within grid distribution equipment, and yield expected predictable results (KSR).
Regarding dependent claim 13, Moore, is silent in regard to:
the network comprising an apparatus according to claim 12.
However, Clarke, further teaches:
the network comprising an apparatus according to claim 12 ([Col. 5, ll. 34-68] & [Col. 6, ll. 1-12 & 38-45]: teaches the network includes such apparatus).
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate the network comprising an apparatus according to claim 12, of Clarke to Moore, according to known methods. Where Moore and Clarke together establish the art of a cast resin bushing with embedded capacitor electrodes for voltage measurement. Clark teaches the environment in which these devices operate: a power distribution network (often part of a national grid), and describes mounting the apparatus on overhead lines of a “24 kV power distribution system,”. Therefore, it would have been obvious to a POSITA that the electrical apparatus (switchgear/transformer) containing the sensored bushing is a constituent part of the larger power distribution network described by Clarke. The fundamental purpose of the bushing is to improve and facilitate the distribution and monitoring of power within that power grid, and yield expected predictable results (KSR).
Moore, and Clarke, are silent in regard to:
Power distribution network of a national grid for distributing electrical power at medium or high voltages,
However, Ferraro, further teaches:
Power distribution network of a national grid for distributing electrical power at medium or high voltages ([0001]-[0002] & [0004] : mentions the grid/network),
It would have been obvious to one of ordinary skill in the art before the effective filing date to incorporate a Power distribution network of a national grid for distributing electrical power at medium or high voltages, of Ferraro, to Moore and Clarke, according to known methods. Where Moore and Clarke together establish the art of a cast resin bushing with embedded capacitor electrodes for voltage measurement. Clarke and Ferraro teach the environment in which these devices operate: a power distribution network (often part of a national grid). Where Clarke describes mounting the apparatus on overhead lines of a “24 kV power distribution system,”. Ferraro describes the need for such sensors in the ”Smart Grid” and “electrical power distribution network”, where it would have been obvious to a POSITA that the electrical apparatus (switchgear/transformer) containing the sensored bushing is a constituent part of the larger power distribution network described by Clarke and Ferraro. The fundamental purpose of the bushing is to improve and facilitate the distribution and monitoring of power within that power grid, and yield expected predictable results (KSR).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Engels et al (US2021/0366632A1) discloses a pluggable high-voltage bushing and electrical device having the pluggable high-voltage bushing. Rashkes et al. (US2002/0079906A1) discloses an electrical system with capacitance tap and sensor for on-line monitoring the state of high-voltage insulation and remote monitoring device. Smith et al. (US2002/0079903A1) discloses an electrical system with a stress shield system for partial discharge on-line monitoring of the state of high-voltage insulation.
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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/HUGO NAVARRO/ Examiner, Art Unit 2858 April 15, 2026
/EMAN A ALKAFAWI/ Supervisory Patent Examiner, Art Unit 2858 4/24/2026
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