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 .
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Election/Restrictions
Applicant’s election without traverse of claims 1-12, and the withdrawal of claims 13-20, in the reply filed on July 9, 2026, are acknowledged.
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.
Claim 2 is 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 pre-AIA the applicant regards as the invention.
Regarding claim 2, there is insufficient antecedent basis for the limitation “the flow rate” in the phrase “to circulate the etching solution through the heat exchanger coil at the flow rate”. For the purpose of this examination, the examiner interprets the limitation as “a flow rate”.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office Action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1, 5-6 and 11-12 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Miljkovic et al. (US20220373271).
Regarding claim 1, Miljkovic discloses a method for improving boiling heat transfer in a heat exchanger coil of a heating, ventilation, and air conditioning (HVAC) system (paragraph 0032), the method comprising: providing the heat exchanger coil, the heat exchanger coil having an outer diameter and an inner diameter and configured to contain and exchange thermal energy with a refrigerant fluid, the inner diameter having a first surface area and a first amount of nucleate boiling sites (aluminium tube as a heart transfer component reads on a heat exchanger coil, paragraph 0032 and claim 14); providing an etching solution (HCl solution reads on an etching solution, claim 14); and applying the etching solution to the inner diameter of the heat exchanger coil, wherein, after applying the etching solution, the inner diameter of the heat exchanger coil has a second surface area larger than the first surface area and a second amount of nucleate boiling sites larger than the first amount of nucleate boiling sites (claim 14 and paragraph 0033).
Regarding claim 5, Miljkovic discloses before applying the etching solution to the inner diameter of the heat exchanger coil: applying a first fluid comprising acetone to the inner diameter of the heat exchanger coil; and applying, after applying the first fluid, a second fluid comprising Isopropyl Alcohol (ISA) to the inner diameter of the heat exchanger coil (claim 16).
Regarding claim 6, Miljkovic discloses applying, after applying the second fluid, deionized water to the inner diameter of the heat exchanger coil (claim 16).
Regarding claim 11, Miljkovic discloses wherein the heat exchanger coil is made of aluminum (abstract and claim 14).
Regarding claim 12, Miljkovic discloses forming a round tube plate heat exchanger using the heat exchanger coil (paragraphs 0009 and 0049).
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 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Miljkovic et al. (US20220373271) as applied to claim 1 above, in view of Wang et al. (CN118668196, a machine-translated English version is used).
Regarding claim 2, Miljkovic fails to disclose connecting the heat exchanger coil to a pump and a flow meter, the pump adapted to circulate the etching solution through the heat exchanger coil at a flow rate, and the flow meter adapted to measure the flow rate, wherein the etching solution is applied to the inner diameter of the heat exchanger coil by pumping the etching solution into the heat exchanger coil using the pump. However, Miljkovic discloses that the etching solution comprises HCl and is used to etch the inner surface of a heat exchange tube (paragraph 0032 and claim 14). In addition, Wang teaches that an etching solution comprising HCl used to etch the inner surface of a heat exchange tube can be supplied by connecting the heat exchanger tube to a pump adapted to circulate the etching solution through the heat exchanger tube at a flow rate between 1L/min to 3L/min, wherein the etching solution is applied to the inner diameter of the heat exchanger tube by pumping the etching solution into the heat exchanger coil using the pump (paragraphs 0010-0013). Therefore, it would have been obvious to one of ordinary skill, in the art before the effective filing date of the claimed invention, to use a known method of providing the etching solution as taught by Wang, in the method of Miljkovic for etching the inner surface of the heat exchange tube, with a reasonable expectation of success. It has been held that combining prior art elements according to known methods to yield predictable results is obvious. See MPEP 2143 I.(A).
Claims 3 and 9-10 are rejected under 35 U.S.C. 103 as being unpatentable over Miljkovic et al. (US20220373271) in view of Wang et al. (CN118668196, a machine-translated English version is used) as applied to claims 1-2 above.
Regarding claim 3, Miljkovic discloses wherein the etching solution comprises hydrochloric acid (HCl) and a molarity of the HCl of the etching solution is 2 to 5 molars, and wherein the etching solution is applied for a set period of time of 7 min to 30 min (claims 14-15), which overlaps with the time range recited in the instant claim. In addition, Wang discloses wherein the etching solution is applied at a flow rate of 0.26 to 0.79 gallons per minute (1L/min – 3 L/min, paragraph 0013), which overlaps with the flow rate range recited in the instant claim. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I).
Regarding claim 9, Miljkovic discloses wherein the etching solution comprises hydrochloric acid (HCl) and a molarity of the HCl of the etching solution is 2 to 5 molars (claim 15), which overlaps with the time range recited in the instant claim. In addition, Wang discloses wherein the etching solution is applied at a flow rate of 0.26 to 0.79 gallons per minute (1L/min – 3 L/min, paragraph 0013), which overlaps with the flow rate range recited in the instant claim. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I).
Regarding claim 10, Miljkovic fails to disclose wherein the etching solution is applied to the inner diameter of the heat exchanger for a set period of time of 5 seconds to 30 seconds. However, an etch time is a process parameter routinely optimized by one of ordinary skill in the art. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable range by routine experimentation and there is no evidence of the criticality of the claimed range. See MPEP 2144.05II.
Claims 7-8 are rejected under 35 U.S.C. 103 as being obvious over Miljkovic et al. (US20220373271) as applied to claim 1 above.
Regarding claim 7, Miljkovic discloses a cleaning process comprising: applying a first fluid comprising acetone to the inner diameter of the heat exchanger coil; and applying, after applying the first fluid, a second fluid comprising Isopropyl Alcohol (ISA) to the inner diameter of the heat exchanger coil (claim 16). Miljvovic is silent about the same cleaning process is performed after applying the etching solution to the inner diameter of the heat exchanger. However, it would have been obvious to one of ordinary skill, in the art before the effective filing date of the claimed invention, to use the known cleaning process to clean the inner diameter of the heat exchange coil after applying the etching solution to the inner diameter of the heat exchanger, with a reasonable expectation of success.
Regarding claim 8, Miljkovic discloses after applying the second fluid, deionized water to the inner diameter of the heat exchanger coil (claim 16).
Allowable Subject Matter
Claim 4 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
Regarding claim 4, the cited prior art of record, taken either alone or in combination, fails to disclose or render obvious a method comprising: expanding, before applying the etching solution to the inner diameter of the heat exchanger coil, the inner diameter and the outer diameter of the heat exchanger coil, in the context of the instant claim.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JIONG-PING LU whose telephone number is (571) 270-1135. The examiner can normally be reached on M-F: 9:00am – 5:00pm. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Joshua L Allen, can be reached at telephone number (571)270-3176. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JIONG-PING LU/
Primary Examiner, Art Unit 1713
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