Prosecution Insights
Last updated: April 19, 2026
Application No. 18/438,516

HEAT EXCHANGER ASSEMBLY OF THERMAL RETENTION APPARATUS FOR HEATING A LIQUID ON DEMAND

Non-Final OA §102§103§112
Filed
Feb 11, 2024
Examiner
RUPPERT, ERIC S
Art Unit
3763
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Phasestor LLC
OA Round
1 (Non-Final)
59%
Grant Probability
Moderate
1-2
OA Rounds
2y 10m
To Grant
83%
With Interview

Examiner Intelligence

Grants 59% of resolved cases
59%
Career Allow Rate
437 granted / 739 resolved
-10.9% vs TC avg
Strong +24% interview lift
Without
With
+24.1%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
55 currently pending
Career history
794
Total Applications
across all art units

Statute-Specific Performance

§101
0.4%
-39.6% vs TC avg
§103
48.5%
+8.5% vs TC avg
§102
21.1%
-18.9% vs TC avg
§112
27.3%
-12.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 739 resolved cases

Office Action

§102 §103 §112
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 . 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 15, 22, 29 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Regarding claim 15/22/29, the recitation “wherein fluid flow through the fluid paths of each said heat exchanger module that form part of the second fluid pathways of the PCM charging circuit is further divided into passageways for parallel fluid flow through said heat exchanger module” is unclear. Specifically, the “second fluid pathways of the PCM charging circuit” lacks antecedent basis. While “second fluid pathways” are previously recited, they are of the discharging circuit, not the charging circuit, which results in further confusion. 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. (a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Claim(s) 11-12, 14-15, 24-26, 28-29 is/are rejected under 35 U.S.C. 102 (a) (1) as being anticipated by Huang (CN111637773A). Regarding claim 11, Huang discloses a heat exchanger assembly (2 & 3) immersed in a phase change material (4), the heat exchanger assembly comprising:(a) first fluid pathways (2) connected to and extending through the phase change material between a first pair of an inlet fluid conduit (21) and an outlet fluid conduit (22) for charging the phase change material by a fluid flowing therethrough having a temperature greater than that of the phase change material, the first fluid pathways defining a phase change material (PCM) charging circuit; (b) second fluid pathways (3) connected to and extending through the phase change material between a second pair of an inlet fluid conduit (31) and an outlet fluid conduit (32) for discharging the phase change material by a fluid flowing therethrough having a temperature less than that of the phase change material, the second fluid pathways defining a PCM discharging circuit; (c) a plurality of heat exchanger modules (see uppermost three sets of layers of 2 & 3) immersed within the phase change material, each defining fluid paths therethrough forming part of the first fluid pathways of the PCM charging circuit and the second fluid pathways of the PCM discharging circuit; (d) a first manifold conduit (211) configured to divide fluid flow from the inlet conduit of the PCM charging circuit into: (i) a first fluid path of a first heat exchanger module to the exclusion of a second of the heat exchanger modules, and (ii) a second fluid path through the second heat exchanger module to the exclusion of the first heat exchanger module; and (e) a second manifold conduit (221) configured to reconsolidate fluid flow from the first and second fluid paths into the outlet conduit of the PCM charging circuit, whereby fluid flow through the first and second heat exchanger modules in the PCM charging circuit is in parallel. Regarding claim 12, Huang discloses the limitations of claim 11, and Huang further discloses a module- interconnecting conduit (see U-shaped connecting conduit connecting each layer of 3) in the PCM discharging circuit that conducts fluid flow from a first fluid path through a first heat exchanger module to a fluid path through a second heat exchanger module, whereby fluid flow through the first and second heat exchanger modules in the PCM discharging circuit is in series. Regarding claim 14, Huang discloses the limitations of claim 11, and Huang further discloses fluid flow through the fluid paths of each said heat exchanger module that form part of the first fluid pathways of the PCM charging circuit is further divided into passageways (see further division from 211 to 23) for parallel fluid flow through said heat exchanger module. Regarding claim 15, Huang discloses the limitations of claim 11, and Huang further discloses fluid flow through the fluid paths of each said heat exchanger module that form part of the second fluid pathways of the PCM charging circuit is further divided into passageways (see further division from 211 to 23) for parallel fluid flow through said heat exchanger module. Regarding claim 24, Huang discloses a heat exchanger assembly (2 & 3) immersed in a phase change material (4), the heat exchanger assembly comprising:(a) first fluid pathways (2) connected to and extending through the phase change material between a first pair of an inlet fluid conduit (21) and an outlet fluid conduit (22) for charging the phase change material by a fluid flowing therethrough having a temperature greater than that of the phase change material, the first fluid pathways defining a phase change material (PCM) charging circuit; (b) second fluid pathways (3) connected to and extending through the phase change material between a second pair of an inlet fluid conduit (31) and an outlet fluid conduit (32) for discharging the phase change material by a fluid flowing therethrough having a temperature less than that of the phase change material, the second fluid pathways defining a PCM discharging circuit; (c) a plurality of heat exchanger modules (see uppermost three sets of layers of 2 & 3) immersed within the phase change material and configured such that fluid flow in the PCM charging circuit is arranged in parallel, fluid flowing through one of the heat exchanger modules only passing through that one heat exchanger module in completing a lap of the PCM charging circuit. Regarding claim 25, Huang discloses the limitations of claim 24, and Huang further discloses the heat exchanger assembly comprises a plurality of heat exchanger modules (sets of layers of 3 & 2) immersed within the phase change material, and wherein fluid flow in the PCM discharging circuit is arranged in series conduit (see U-shaped connecting conduit connecting each layer of 3 in series) such that fluid flow passes through all of the heat exchanger modules in completing a lap of the PCM discharging circuit. Regarding claim 26, Huang discloses the limitations of claim 25, and Huang further discloses module- interconnecting conduits connect the heat exchanger modules in series (see U-shaped connecting conduit connecting each layer of 3). Regarding claim 28, Huang discloses the limitations of claim 24, and Huang further discloses fluid flow through the fluid paths of each said heat exchanger module that form part of the first fluid pathways of the PCM charging circuit is further divided into passageways (see further division from 211 to 23) for parallel fluid flow through said heat exchanger module. Regarding claim 29, Huang discloses the limitations of claim 24, and Huang further discloses fluid flow through the fluid paths of each said heat exchanger module that form part of the second fluid pathways of the PCM charging circuit is further divided into passageways (see further division from 211 to 23) for parallel fluid flow through said heat exchanger module. Claim(s) 11, 16-18, 23-24, 30 is/are rejected under 35 U.S.C. 102 (a) (1) or 102 (a) (2) as being anticipated by Bauman (US20220390152A1). Regarding claim 11, Bauman teaches heat exchanger assembly (see Fig. 14-17) immersed in a phase change material (see abstract), the heat exchanger assembly comprising:(a) first fluid pathways (174) connected to and extending through the phase change material between a first pair of an inlet fluid conduit and an outlet fluid conduit for charging the phase change material by a fluid flowing therethrough having a temperature greater than that of the phase change material, the first fluid pathways defining a phase change material (PCM) charging circuit; (b) second fluid pathways (170) connected to and extending through the phase change material between a second pair of an inlet fluid conduit and an outlet fluid conduit for discharging the phase change material by a fluid flowing therethrough having a temperature less than that of the phase change material, the second fluid pathways defining a PCM discharging circuit; (c) a plurality of heat exchanger modules (pairs of 170 & 174) immersed within the phase change material, each defining fluid paths therethrough forming part of the first fluid pathways of the PCM charging circuit and the second fluid pathways of the PCM discharging circuit; (d) a first manifold conduit (166) configured to divide fluid flow from the inlet conduit of the PCM charging circuit into: (i) a first fluid path of a first heat exchanger module to the exclusion of a second of the heat exchanger modules, and (ii) a second fluid path through the second heat exchanger module to the exclusion of the first heat exchanger module; and (e) a second manifold conduit (166) configured to reconsolidate fluid flow from the first and second fluid paths into the outlet conduit of the PCM charging circuit, whereby fluid flow through the first and second heat exchanger modules in the PCM charging circuit is in parallel. Regarding claim 16, Bauman discloses the limitations of claim 11, and Bauman further discloses the heat exchanger modules (pairs of 170 & 174) are horizontally arranged next to each other, and the first and second manifolds (166) are vertically arranged over top of the heat exchanger modules. Regarding claim 17, Bauman discloses a heat exchanger assembly (Fig. 14-17) immersed in a phase change material, the heat exchanger assembly comprising,(a) first fluid pathways (174) connected to and extending through the phase change material between a first pair of an inlet fluid conduit and an outlet fluid conduit for charging the phase change material by a fluid flowing therethrough having a temperature greater than that of the phase change material, the first fluid pathways defining a phase change material (PCM) charging circuit; (b) second fluid pathways (170) connected to and extending through the phase change material between a second pair of an inlet fluid conduit and an outlet fluid conduit for discharging the phase change material by a fluid flowing therethrough having a temperature less than that of the phase change material, the second fluid pathways defining a PCM discharging circuit; (c) five heat exchanger modules (see five pairs of 170 & 174) immersed within the phase change material, each defining fluid paths therethrough forming part of the first fluid pathways of the PCM charging circuit and the second fluid pathways of the PCM discharging circuit; (d) a manifold conduit (166) configured to divide fluid flow from the inlet conduit of the PCM charging circuit into each of five fluid paths each fluid path corresponding to a respective one of the five heat exchanger modules to the exclusion of the other heat exchanger modules; and (e) a manifold conduit (166) configured to reconsolidate fluid flow from the five fluid paths into the outlet conduit of the PCM charging circuit, whereby fluid flow through the five heat exchanger modules in the PCM charging circuit is in parallel. Regarding claim 18, Bauman discloses the limitations of claim 17, and Bauman further discloses approximately twenty percent of fluid flow passes through each of the plurality of heat exchanger modules (see flow through one of the five modules as identified above). Regarding claim 23, Bauman discloses the heat exchanger modules (pairs of 170 & 174) are horizontally arranged next to each other, and the first and second manifolds (166) are vertically arranged over top of the heat exchanger modules. Regarding claim 24, Bauman discloses a heat exchanger (Fig. 14-17) assembly immersed in a phase change material (see abstract), the heat exchanger assembly comprising,(a) first fluid pathways (174) connected to and extending through the phase change material between a first pair of an inlet fluid conduit and an outlet fluid conduit for charging the phase change material by a fluid flowing therethrough having a temperature greater than that of the phase change material, the first fluid pathways defining a phase change material (PCM) charging circuit; (b) second fluid pathways (170) connected to and extending through the phase change material between a second pair of an inlet fluid conduit and an outlet fluid conduit for discharging the phase change material by a fluid flowing therethrough having a temperature less than that of the phase change material, the second fluid pathways defining a PCM discharging circuit; and (c) a plurality of heat exchanger modules (pairs of 170 & 174) immersed within the phase change material and configured such that fluid flow in the PCM charging circuit is arranged in parallel, fluid flowing through one of the heat exchanger modules only passing through that one heat exchanger module in completing a lap of the PCM charging circuit. Regarding claim 30, Bauman discloses the limitations of claim 24, and Bauman further discloses wherein the heat exchanger modules (pairs of 170 & 174) are horizontally arranged next to each other, and the first and second manifolds (166) are vertically arranged over top of the heat exchanger modules. 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. Claim(s) 17-19, 21-22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang (CN111637773A). Regarding claim 17, Huang teaches a heat exchanger assembly (2 & 3) immersed in a phase change material (4), the heat exchanger assembly comprising:(a) first fluid pathways (2) connected to and extending through the phase change material between a first pair of an inlet fluid conduit (21) and an outlet fluid conduit (22) for charging the phase change material by a fluid flowing therethrough having a temperature greater than that of the phase change material, the first fluid pathways defining a phase change material (PCM) charging circuit; (b) second fluid pathways (3) connected to and extending through the phase change material between a second pair of an inlet fluid conduit (31) and an outlet fluid conduit (32) for discharging the phase change material by a fluid flowing therethrough having a temperature less than that of the phase change material, the second fluid pathways defining a PCM discharging circuit; (c) a plurality of heat exchanger modules (see uppermost three sets of layers of 2 & 3) immersed within the phase change material, each defining fluid paths therethrough forming part of the first fluid pathways of the PCM charging circuit and the second fluid pathways of the PCM discharging circuit; (d) a first manifold conduit (211) configured to divide fluid flow from the inlet conduit of the PCM charging circuit into: (i) a first fluid path of a first heat exchanger module to the exclusion of a second of the heat exchanger modules, and (ii) a second fluid path through the second heat exchanger module to the exclusion of the first heat exchanger module; and (e) a second manifold conduit (221) configured to reconsolidate fluid flow from the first and second fluid paths into the outlet conduit of the PCM charging circuit, whereby fluid flow through the first and second heat exchanger modules in the PCM charging circuit is in parallel. While Huang does not teach five such modules, but rather three, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified Huang to include five modules, since it has been held that mere duplication of the essential working parts of a device involves only routine skill in the art. (See MPEP 2144.04 VI. B.). Regarding claim 18, Huang teaches the limitations of claim 17, and Huang further teaches approximately twenty percent of fluid flow passes through each of the plurality of heat exchanger modules (as modified above). Regarding claim 19, Huang teaches the limitations of claim 17, and Huang further teaches four module-interconnecting conduits in the PCM discharging circuit each conducting fluid flow from a fluid path through a heat exchanger module to a fluid path through another heat exchanger module such that fluid flow through the five heat exchanger modules in the PCM discharging circuit (3) is in series (as modified above). Regarding claim 21, Huang teaches the limitations of claim 17, and Huang further teaches fluid flow through the fluid paths of each said heat exchanger module that form part of the first fluid pathways of the PCM charging circuit is further divided into passageways (23) for parallel fluid flow through said heat exchanger module. Regarding claim 22, Huang teaches the limitations of claim 17, and Huang further teaches fluid flow through the fluid paths of each said heat exchanger module that form part of the second fluid pathways of the PCM charging circuit is further divided into passageways (23) for parallel fluid flow through said heat exchanger module. Claim(s) 13/20/27 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bauman (US20220390152A1) in view of Munekawa (JPS6321489A). Regarding claim 13/20/27, Bauman teaches the limitations of claim 11/17/24, and Bauman further teaches the passageways of each said heat exchanger module comprise copper tubing and fins configured to transfer heat between the phase change material and fluid flowing through the passageways (copper- abstract), however, fails to teach wherein the fins are aluminum. Munekawa teaches wherein the tubes are copper and the fins are aluminum (page 2). Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified Bauman to include the copper tube and aluminum fins of Munekawa, in order to provide materials having high thermal conductivity. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to ERIC S RUPPERT whose telephone number is (571)272-9911. The examiner can normally be reached Monday - Friday 8 am - 4 pm. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Len Tran can be reached at 571-272-1184. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /ERIC S RUPPERT/Primary Examiner, Art Unit 3763
Read full office action

Prosecution Timeline

Feb 11, 2024
Application Filed
Mar 05, 2026
Non-Final Rejection — §102, §103, §112 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
59%
Grant Probability
83%
With Interview (+24.1%)
2y 10m
Median Time to Grant
Low
PTA Risk
Based on 739 resolved cases by this examiner. Grant probability derived from career allow rate.

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