DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 03/17/2026. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Rejections - 35 USC § 103
The following is a quotation of AIA 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived by the manner in which the invention was made.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under AIA 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.
Claims 13-20 are rejected under 35 U.S.C. 103 as being unpatentable over Wilcox (WO 2010107651 A2), in view of Vempati (US 20120061379 A1).
Regarding claim 13, Wilcox discloses
An electrical heater (system 100, fig.2) for heating an air stream, the electrical heater (system 100) comprising:
one or more electrical heating elements (radiant coil 117, fig.2) disposed in an electrically heated radiant section (steam superheater H-1, fig.1);
one or more heating elements (connective coil 112, fig.2) disposed in an electrically heated convention section (convection section H-2, fig.2), the electrically heated convection section (convection section H-2) located upstream of the electrically heated radiant section (steam superheater H-1);
wherein the electrical heater is configured for heating the air stream to a temperature in the range of 500-800° C [Page 9, lines 2-3 cited: “…main steam emerges from convection coil 112 into line 114 at a temperature of from about 540C to 560C…”].
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However, Wilcox does not disclose one or more surface area increasing features attached to the one or more heating elements; a ceramic refractory material configured for adsorbing a radiant heat from the one or more electrical heating elements and transferring the heat to the air stream by convection.
Vempati discloses one or more surface area increasing features (ceramic honeycomb monolith body 6, fig.1) attached to the one or more heating elements (electrical resistance heating element 5, fig.1); and a ceramic refractory material [Par.0048 cited: “…ceramic honeycomb monolith body made of Zirconia, Alumina, Mullite or any other suitable non conducting refractory material…”] configured for adsorbing a radiant heat from the one or more electrical heating elements (electrical resistance heating element 5) and transferring the heat to the air stream by convection.
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It would have been obvious to one of ordinary skill in the art at before the effective filling date of the invention to modify an electric heater of Wilcox, by including one or more surface area increasing features attached to the one or more heating elements; a ceramic refractory material configured for adsorbing a radiant heat from the one or more electrical heating elements and transferring the heat to the air stream by convection, as taught by Vempati, in order to improve amount of heat conductivity.
Regarding claim 14, Wilcox discloses
the one or more electrical heating elements (radiant coil 117, fig.2) disposed in the electrically heated radiant section (steam superheater H-1, fig.1) and the one or more electrical heating elements (connective coil 112, fig.2) disposed in the electrically heated convection section (steam superheater H-1, fig.1) comprise one or more wires [connective coil 112, fig.2, is wire].
Regarding claim 15, the modification of Wilcox and Vempato does not disclose the one or more wires are made of a NiCr alloy capable of operating up to 1100° C.
Regarding claim 16, the modification of Wilcox and Vempato does not disclose
the one or more wires are made of a FeCrAl alloy capable of operating up to 1300° C.
Regarding claim 17, the modification of Wilcox and Vempato does not disclose the one or more wires are made of a MoSi2 alloy capable of operating up to 1850° C.
Regarding claim 18, the modification of Wilcox and Vempato does not disclose the one or more wires are made of a SiC alloy capable of operating up to 1600° C.
It would have been obvious to one of ordinary skill in the art at before the effective filling date of the invention to modify an electric heater of Wilcox, with one or more wires are made of a NiCr alloy capable of operating up to 1100° C; one or more wires are made of a FeCrAl alloy capable of operating up to 1300° C; one or more wires are made of a MoSi2 alloy capable of operating up to 1850° C; and one or more wires are made of a SiC alloy capable of operating up to 1600° C, as it well known in the art of manufacturing design choice purpose, in order to improve an electrically conductivity.
Regarding claim 19, Vempati discloses
the one or more surface area increasing features (ceramic honeycomb monolith body 6, fig.1) are in a shape selected from the group consisting of a rectangular fin, a circulate fin, a plate, and a spike [ceramic honeycomb monolith body 6, fig.1, can be a shape of a rectangular fin, a circulate fin, a plate, and a spike].
It would have been obvious to one of ordinary skill in the art at before the effective filling date of the invention to modify an electric heater of Wilcox, by including one or more surface area increasing features are in a shape selected from the group consisting of a rectangular fin, a circulate fin, a plate, and a spike, as taught by Vempati, in order to improve amount of heat conductivity.
Regarding claim 20, the modification of Wilcox and Vempato does not disclose
the electrical heater is configured to transfer 30 to 300 MW energy and has a working voltage in a range from 300 V to 7000 V.
It would have been obvious to one of ordinary skill in the art at before the effective filling date of the invention to modify an electric heater of Wilcox, with transfer 30 to 300 MW energy and has a working voltage in a range from 300 V to 7000 V, as it well known in the art of manufacturing design choice purpose, in order suitable for the user application.
Response to Amendment
Applicant's amendment filed on 03/31/2026, that overcame the Claim Objection in the previous office action.
Response to Argument
Applicant's arguments filed on 03/31/2026 have been fully considered but they are not persuasive as the following reasons:
The applicant’s argued: “…Wilcox does not disclose the specific upstream/downstream arrangement of the convection and radiant sections for heating air, as described in the claims set forth. Specifically, Wilcox does not teach an electrical heater for heating an air stream to a temperature in the range of 500-800°C with an electrically heated convection section comprising heating elements with surface area increasing features attached thereto and an electrically heated radiant section comprising ceramic refractory material configured to absorb radiant heat from electrical heating elements and transfer the heat to the air stream by convection, as required by limitations (i)-(iv) of independent claim 13.… Further, Wilcox fails to teach the internal structure of the steam heater or "electric furnace." Applicant respectfully submits that there is no teaching of how to arrange any electric heating elements within an electric furnace, no suggestion of finned or surface area increasing elements in a convection section, and no disclosure of ceramic refractory configured to absorb radiant heat and transfer it convectively. … ”
The examiner’s response: the applicant’s argument is not persuasive because in response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). In this case, the secondary Vempato reference is only used to disclose the limitations in fig.1, with surface area increasing features (ceramic honeycomb monolith body 6, fig.1) attached to the one or more heating elements (electrical resistance heating element 5, fig.1); and a ceramic refractory material [Par.0048 cited: “…ceramic honeycomb monolith body made of Zirconia, Alumina, Mullite or any other suitable non conducting refractory material…”], it is noted that Zirconia, Alumina, Mullite.. are well known as a refractory material.
All the other limitations are disclosed by the primary Wilcox reference, such as the electrical heater (system 100, fig.2) is configured for heating the air stream (steam, Page 9, lines 2-3) to a temperature in the range of 500-800° C. See Page 9, lines 2-3 cited: “…main steam emerges from convection coil 112 into line 114 at a temperature of from about 540C to 560C…”. For reasonable broadly interpretation, “steam” is considered as “air stream” because they are both can do same perform as flowing air from water.
In response to applicant's argument that the references fail to show certain features of applicant’s invention, it is noted that the features upon which applicant relies (i.e., “…Wilcox fails to teach the internal structure of the steam heater or "electric furnace." Applicant respectfully submits that there is no teaching of how to arrange any electric heating elements within an electric furnace, no suggestion of finned or surface area increasing elements in a convection section…”) 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). In this case, steam heater, electric furnace, and arrange any electric heating elements within an electric furnace… are not recited in the present independent claim 13 as mentioned by the applicant.
Conclusion
THIS ACTION IS MADE FINAL. 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 extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to PHUONG T NGUYEN whose telephone number is (571)270-1834. The examiner can normally be reached 9.00am-5.00pm.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Steven Crabb can be reached on 571-270-5095. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/PHUONG T NGUYEN/Primary Examiner, Art Unit 3761
04/22/2026
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