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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 11 May 2026 has been entered.
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 6, 11, and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Japanese Publication No. 2000-320914 A to Yabu et al. in view of Japanese Publication No. 2014/020673A to Saito et al. and US Publication No. 2016/0131368 A1 to Tomoigawa.
An English translation of Yabu has been provided with the Nonfinal Rejection of 12 June 2025 and citations to specific passages and paragraphs of this reference are directed to this translation rather than to the Japanese-language original document. Further, an English translation of Saito has been provided with the Final Rejection of 9 December 2025 and citations to specific passages and paragraphs of this reference are directed to this translation rather than to the English-language original document.
PNG
media_image1.png
247
228
media_image1.png
Greyscale
Yabu teaches limitations from claim 6 in fig. 1, shown above, a refrigeration cycle apparatus, comprising
a second outdoor heat exchanger (23),
a use heat exchanger (11) including a first use flow path (receiving refrigerant circulated by the compressor 10),
a cascade heat exchanger (4) including a first cascade flow path (13, receiving refrigerant circulated by the compressor 10 in circuit 2) and a second cascade flow path (21, receiving refrigerant circulated by the compressor 20 in circuit 3) that is independent of the first cascade flow path (as shown in fig. 1, the two paths 13 and 21 communicate only thermally), and configured to heat exchange between a first refrigerant (in circuit 2) and a second refrigerant (in circuit 3), and
[wherein the refrigeration cycle apparatus is configured to perform]
a heating operation by performing a two-stage refrigeration cycle by evaporating the second refrigerant (in cycle 3) in the second outdoor heat exchanger (23), radiating heat from the second refrigerant in the second cascade flow path (21), evaporating the first refrigerant (in cycle 2) in the first cascade flow path (13, and radiating heat from the first refrigerant in the first use flow path (in the heat exchanger 11, taught in the Solution portion of the abstract of Yabu, the indoor heat exchanger 11 of the high-temperature cycle 2 functions as a condenser to heat indoor air and as taught in ¶ 29 the heating operation may be performed using a dual refrigeration cycle with both cycles 2 and 3 to in the event of a low outside air temperature); and
a cooling operation by performing a two-stage refrigeration cycle by evaporating the first refrigerant (in cycle 2) in the first cascade flow path (13), radiating heat from the second refrigerant (in cycle 3) in the second cascade flow path (21).
Yabu does not teach system including a first outdoor heat exchanger for radiating heat from the first refrigerant in the cooling operation, a controller for switching the operations of the refrigeration cycle apparatus, or the refrigerants in the first and second refrigerants being chosen such that the first refrigerant has 1 MPa or less at 30ºC and the second refrigerant has 1.5 MPa or more at 30ºC.
PNG
media_image2.png
310
326
media_image2.png
Greyscale
Saito teaches in fig. 1, shown above, a refrigeration air conditioning system having an outdoor unit (1) and an indoor unit (2) and having a high-source refrigeration cycle (formed having a compressor 5, radiator 6, expansion valve 8, and a first path 9a of a cascade heat exchanger 9) and a low-source refrigeration cycle (having a compressor 10, switching valve 11, radiator 12, a second path 9b of the cascade heat exchanger 9, expansion valve 14, and indoor heat exchanger 15) so that the indoor heat exchanger (15) functions as the use heat exchanger of claim 1 and the radiator (12) functions as the first outdoor heat exchanger of claim 1 when an operation is performed using only the low-source refrigeration cycle (as taught in ¶ 29-30 of Saito as a “unit operation”). Saito further teaches a control device (20) having a microcomputer and operating to control and switch operations of the refrigeration cycles. Further, Saito teaches in ¶ 22 that the refrigerant circulating in the low-source refrigeration cycle (equivalent to the claimed “second refrigerant”) is carbon dioxide (taught by applicant in ¶ 26 of the instant application (as numbered in US Publication No. 2024/0027105 A1) as an exemplary refrigerant having a pressure of 1.5 MPa or more at 30º C) and in ¶ 25 that the refrigerant circulating in the low-source refrigeration cycle (equivalent to the claimed “first refrigerant”) is R290 (commonly known as propane). The “Temperature-Pressure Chart for Propane (R290)” document (included with this Office Action and retrieved from https://berg-group.com/wp-content/uploads/2024/08/Berg-Propane-R290-Pressure-Temperature-Chart.pdf) shows R290/Propane to have a pressure of “141.8 psig” (equal to 0.977 MPa) at a temperature of 30º C, showing that Saito teaches this limitation of the instant claim. It would have been obvious to one of ordinary skill in the art before the application was effectively filed to modify Yabu with the outdoor heat exchanger, controller, and refrigerants taught by Saito because these refrigerants are well known as effective, reliable, and useful refrigerants in common use in refrigeration systems, with R290 known as an energy-efficient, high performance refrigerant with a low global warming potential (GWP) and carbon dioxide is likewise known as a safe and efficient refrigerant with low GWP and further because the use of an outdoor heat exchanger (rather than only providing the cascade heat exchanger to receive heat removed from the conditioned space in a cooling operation increases the capacity of refrigeration circuit by more efficiently rejecting heat from the refrigerant.
Further, Yabu does not teach the use heat exchanger of the system including a second use flow path for evaporating the second refrigerant in a cooling operation.
PNG
media_image3.png
289
416
media_image3.png
Greyscale
PNG
media_image4.png
349
596
media_image4.png
Greyscale
Tomoigawa teaches in figs. 2 and 3, shown below, an indoor unit (12) of an air conditioning system in which an indoor heat exchanger is divided into two sub-heat exchangers (5A and 5B) disposed in two sides (27A and 27B) of a single air outlet (27). Tomoigawa further teaches in ¶ 30 that these two heat exchangers (5A and 5B) are respectively connected to separate and independent refrigerant circuits (circuit 35A, including an outdoor unit 32A and expansion valve 31A, connecting to the heat exchanger 5A and circuit 35B, including an outdoor unit 32B and expansion valve 31B, connecting to the heat exchanger 5B). One of ordinary skill in the art before the application was effectively filed would have found it to be obvious, in modifying Yabu according to the teachings of Tomoigawa, to provide the indoor-unit side circuit (2) of Yabu as one of the two circuits (35A or 35B) of Tomoigawa so that the other circuit (3) of Yabu may still be used to increase the heating capacity of the system in response to increased load (as taught in the Abstract of Yabu) while also allowing the supplemental cooling of the dual heat exchanger of Tomoigawa when operating in a cooling mode, resulting in a system in which one circuit (equivalent to circuit 2 of Yabu) is a use-side circuit in a heating mode and a heat-source side circuit in a cooling mode, circulating the same refrigerant in both cases and using either the secondary circuit of Yabu or that of Tomoigawa depending on which is advantageous for performance and efficiency in the instant operation.
Yabu as modified by Tomoigawa as set forth above teaches limitations from claim 11 in figs. 2 and 3 of Tomoigawa, shown above, the refrigeration cycle apparatus according to claim 8, wherein during the cooling operation, the first refrigerant evaporates when passing through the first use flow path (of the heat exchanger section 5A of Tomoigawa), and the second refrigerant evaporates when passing through the second use flow path (of the heat exchanger section 5B of Tomoigawa, the sections 5A and 5B functioning together as the indoor heat exchanger 11 of Yabu which will act as an evaporator when the flow in the circuit 2 is reversed for a cooling operation as taught in ¶ 88 of Yabu. Further, Tomoigawa teaches in ¶ 31 of his specification that both heat exchangers 5A and 5B of the split heat exchanger of his invention may heat or cool air passing through the indoor unit.)
Yabu as modified by Tomoigawa as set forth above teaches limitations from claim 12 in fig. 1 of Yabu and figs. 2 and 3 of Tomoigawa, shown above, the refrigeration cycle apparatus according to claim 8, wherein during the heating operation, the first refrigerant radiates heat when passing through the first use flow path (of the heat exchanger section 5A of Tomoigawa), and the second refrigerant radiates heat when passing through the second use flow path (of the heat exchanger section 5B of Tomoigawa, the sections 5A and 5B functioning together as the indoor heat exchanger 11 of Yabu which acts as a condenser to release heat to indoor air as taught in the Abstract of Yabu. Further, Tomoigawa teaches in ¶ 31 of his specification that both heat exchangers 5A and 5B of the split heat exchanger of his invention may heat or cool air passing through the indoor unit.)
Response to Arguments
Applicant's arguments filed 11 May 2026 have been fully considered but they are not persuasive.
Applicant argues on pp. 5-6 of the reply that Saito does not teach the limitations presented in claim 1 regarding the switching of the use side heat exchanger (15) between operating as an evaporator in a cooling mode and a condenser in a heating mode.
In response, although examiner agrees with this characterization of Saito, it is noted that Saito has not been relied upon to teach this feature of claim 1 as this feature is already present in the Yabu, the primary reference relied upon in rejecting claim 1 as being obvious in the Final Rejection.
Similarly, applicant argues on pg. 6 of the reply that Yabu does not teach the specific limitations of claim 1 regarding the pressure characteristics of the first and second refrigerants.
In response, examiner again agrees with applicant’s characterization of the prior art but again notes that the reference in question is not relied upon to teach the limitations in question. In this case, Saito rather than Yabu is presented in the Final Rejection to teach the refrigerants of the instant disclosure and thus the pressure characteristics at known temperatures of these refrigerants.
Applicant argues on pg. 6 of the reply that Saito does not teach the R290 refrigerant (present in the outdoor circuit which includes the radiator 6 and corresponding path 9a of the cascade heat exchanger 9 does not fulfill the limitation in lines 11-13 of claim 1 of “evaporating the first refrigerant in the use heat exchanger”.
Again, examiner agrees with this characterization. In this case, the argument is persuasive because neither of the Yabu and Saito references includes the corresponding limitation of the refrigerant (R290 in the Saito reference) which radiates heat in the outdoor heat exchanger flowing to and evaporating in the indoor, use-side heat exchanger. Because neither prior art reference teaches the limitation, the argument is persuasive and the rejection of claim 1 as being obvious over Yabu in view of Saito has been withdrawn.
Applicant argues on pp. 6-7 of the reply with regard to the rejection of claim 6 that the Tomoigawa reference “merely discloses a feature in which the indoor heat exchanger 12 is divided into a heat exchanger belonging to refrigerant circuit 35A and a heat exchanger belonging to refrigerant circuit 35B, with separate circuits connected; it does not describe a relationship in which they are thermally connected via a cascade heat exchanger”.
Once again, applicant has correctly characterized the teachings of a single reference but has not argued with regard to the combination of references on which the rejection is based. In the rejection of claim 6, both Yabu and Saito teach refrigeration systems in which two circuits are thermally connected by a cascade heat exchanger. Besides noting the fact this this feature is not also taught by Tomoigawa, applicant does not present any arguments or explanation why the modification of Yabu with the separated heat exchanger of Tomoigawa would not be obvious or why such modification would negate or remove the cascade arrangement of Yabu’s system. Because this argument addresses only the teachings of Tomoigawa without addressing or presenting reasoning relevant to the combination of references on which the rejection is based, this argument amounts only to a piecemeal attack against the Tomoigawa reference which cannot be found to be persuasive.
Allowable Subject Matter
Claims 1, 3, 5, 15, 16, and 20 are allowed.
Particularly, as noted above in the Response to Augments, neither Yabu nor Saito teaches the limitation found in lines 11-13 of claim 1 of the cooling operating including the first refrigerant both “radiating heat… in the first outdoor heat exchanger and evaporating… in the use heat exchanger” as each of the references teaches this refrigerant circulating only in an outdoor unit separated from the indoor use-side heat exchanger.
Although Saito teaches in fig. 1 a system having an outdoor heat exchanger (12) through which a refrigerant flows which also flows to a number of indoor units (2) and the indoor heat exchangers (15) thereof as well as through a cascade heat exchanger (9) to exchange heat with a refrigerant in an exclusively outdoor cycle (including compressor 5 and radiator 9), the refrigerant flowing in this cycle is taught to be carbon dioxide which exhibits the pressure properties recited in claim 1 for the second refrigerant rather than for the first refrigerant (with the refrigerant in the outdoor cycle of Saito, equivalent to the claimed second refrigerant taught to be R290, exhibiting the pressure properties taught in claim 1 for the first refrigerant).
Saito teaches in ¶ 22 that it is advantageous for carbon dioxide to flow through the so-called “low-source refrigeration cycle” (including the indoor units 15) while combustible R290 flows only in the outdoor unit (1). This teaching is found to constitute a teaching away from a modification such as switching the locations of these refrigerants to arrive at the claimed invention as one of ordinary skill in the art before the application was effectively filed would recognize that doing so would remove the advantages for the refrigerants taught by Saito, increasing the danger posed by the combustible refrigerant in the event of a leak, including the risk of explosion.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DANIEL C COMINGS whose telephone number is (571)270-7385. The examiner can normally be reached Monday - Friday, 8:30 AM to 5 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, Jerry-Daryl Fletcher can be reached at (571)270-5054. 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.
/DANIEL C COMINGS/Examiner, Art Unit 3763
/ELIZABETH J MARTIN/Primary Examiner, Art Unit 3763
Prosecution Insights