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 § 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, 2, 8, 9, 11-13, 17, and 18 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by US2021/0051819 to Gao, hereinafter referred to as Gao.
In reference to claim 1, Gao discloses the claimed invention including:
A cooling system, see figure 5, for a facility (data center) employing equipment (servers) requiring active cooling, the cooling system comprising:
a refrigerant supply line (see annotated reference below for the examiner's definition of the supply line) providing refrigerant from a refrigerant source (250),
a refrigerant return line (see annotated reference below for the examiner's definition of the return line) configured for directing the refrigerant toward the refrigerant source (250) for cooling and recirculating of the refrigerant (external liquid) at the refrigerant source and further toward the refrigerant supply line,
a first heat exchanger (258) configured to use the refrigerant circulating therethrough through the first heat exchanger to cool air or liquid which passes through the first heat exchanger and is used for active cooling of the equipment in the facility, and
a second heat exchanger (260) configured to use the refrigerant circulating through the second heat exchanger to cool air or liquid which passes through the second heat exchanger and is used for active cooling of the equipment in the facility, and
a supplemental heat exchanger (252) fluidly connected to and positioned in-line and downstream of the first heat exchanger (258), the supplemental heat exchanger having a supplemental refrigerant inlet (as defined below) configured to receive the refrigerant directly from the first heat exchanger (258) and a supplemental refrigerant outlet (as defined below) configured to direct the refrigerant toward the refrigerant return line, the supplemental heat exchanger (252) configured to accept the refrigerant (external cooling liquid) from the first heat exchanger (258) for supplemental cooling of the refrigerant and directing the refrigerant toward the refrigerant return line, the supplemental heat exchanger is positioned at a location with an ambient temperature lower than that of the refrigerant coming into the supplemental heat exchanger, at least at some periods during operation of the facility (inferred from [0058-0059] where Gao teaches that the thermal energy from the external cooling liquid to an external fluid (water or air) implies that the water or air would have to be colder in order to receive the thermal energy from the external cooling liquid),
wherein the refrigerant return line originates from a point where refrigerant returning from the first heat exchanger, the second heat exchanger, and the supplemental heat exchanger merge and extends to the refrigerant source (as defined below.
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In reference to claim 2, Gao discloses the claimed invention including:
the supplemental heat exchanger (252) is positioned outside the facility (see [0059] where cold ambient air or water is disclosed as containing external fluid).
In reference to claim 8, Gao discloses the claimed invention including:
wherein the supplemental heat exchanger (252) is positioned downstream of the first and second or more heat exchangers (258/260) and prior to directing the refrigerant to the refrigerant return line.
In reference to claim 9, Gao discloses the claimed invention including:
at least one temperature sensor (203) configured to measure refrigerant temperature at a first refrigerant outlet (223) of the first heat exchanger (see figure 4 for details of the sensor and outlets.)
In reference to claim 11, Gao discloses the claimed invention including:
the liquid passing through the first heat exchanger is one phase refrigerant or two phase refrigerant. Note that the refrigerant flowing through the system will either be a single phase or two phase refrigerant.
In reference to claim 12, Gao discloses the claimed invention including:
the facility is a computer data center [0063] and the air or liquid passing through the first heat exchanger is used for active cooling of computer equipment of the data center.
In reference to claim 13, Gao discloses the claimed invention including:
A method for cooling a facility (data center) employing equipment (servers) requiring active cooling (see figure 5), the method comprising the following steps:
a. directing a refrigerant from a refrigerant supply line (see annotated reference above with respect to claim 1 for the examiner's definition of the supply line) through a first heat exchanger (258) and a second heat exchanger (260), wherein the first heat exchanger (258) is configured to use the refrigerant circulating through the first heat exchanger to cool air or liquid which passes through the first heat exchanger (implied by liquid-to -air heat exchanger) and is used for active cooling of the equipment in the facility, and wherein the second heat exchanger (260) is configured to use the refrigerant circulating through the second heat exchanger to cool air or liquid (implied by liquid-to-liquid) which passes through the second heat exchanger and is used for active cooling of the equipment in the facility, and
b. directing the refrigerant from at least the first heat exchanger (258) and/or the second heat exchanger (260) to a supplemental heat exchanger (252), the supplemental heat exchanger having a supplemental refrigerant inlet configured to receive the refrigerant from the first heat exchanger (258) and/or the second heat exchanger and a supplemental refrigerant outlet (see annotated reference above with respect to claim 1 for the examiner's definition of the supply and return lines) configured to direct the refrigerant toward the refrigerant return line, prior to directing the refrigerant to a refrigerant return line, the refrigerant return line originating from a point where refrigerant returning from the first heat exchanger, the second heat exchanger, and the supplemental heat exchanger merge and extending to a common refrigerant source (see annotated reference above with respect to claim 1).
In reference to claim 17, Gao discloses the claimed invention including:
in step the flow of refrigerant after passing through the supplemental heat exchanger (252) is directed to the refrigerant return line, (see annotated reference above with respect to claim 1 for the examiner's definition of the refrigerant return line).
In reference to claim 18, Gao discloses the claimed invention including:
the facility is a computer data center [0063] and the air or liquid passing through the first heat exchanger is used for active cooling of computer equipment of the data center.
Claims 6 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Gao in view of US 2022/0390178 to Hnayno et al., hereinafter referred to as Hnayno.
In reference to claim 6, Gao and Hnayno disclose the claimed invention.
Gao is silent regarding the one or more temperature sensors configured to detect refrigerant temperature and ambient temperature.
Hnayno teaches that in the art of data center cooling, that it is a known method to provide the system with one or more temperature sensors (161/107) configured to detect refrigerant temperature (107) and ambient temperature (161) [0080 & 0096]. Hnayno teaches using these sensors to control valves pumps of the system [0100]. This is strong evidence that modifying Gao as claimed would produce predictable results (i.e., control the external fluid flowing through the supplemental heat exchange only when the conditions are favorable for cooling the refrigerant within the external cooling loop). Accordingly, it would have been obvious to a person having ordinary skill in the art at the time the invention was effectively filed, to modify Gao by Hnayno such that the system included one or more temperature sensors configured to detect refrigerant temperature and ambient temperature, since all claimed elements were known in the art, and one having ordinary skill in the art could have modified the prior art as claimed by known methods with no changes in their respective functions and the combination would have yielded a predictable result of control the external fluid flowing through the supplemental heat exchange only when the conditions are favorable for cooling the refrigerant within the external cooling loop.
In reference to claim 7, Gao and Hnayno disclose the claimed invention.
Hnayno teaches a controller (512) comprising a processor [0027 & 0047] configured to receive temperature signals from at least the one or more temperature sensors (161/107), wherein the controller is configured to actuate at least one valve (165) direct the refrigerant flow through the supplemental heat exchanger (150) when the refrigerant temperature (161) is above the ambient temperature [0096]. Accordingly, when modifying Gao by Hnayno as applied in claim 6 supra, the limitations of claim 7 would be met by the combination, in order to control the external fluid flowing through the supplemental heat exchange only when the conditions are favorable for cooling the refrigerant within the external cooling loop.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Gao in view of CN108834366 to Cai et al., hereinafter referred to as Cai, (see English language translation provided with the non-final Office action mailed March 24, 2026).
In reference to claim 10, Gao and Cai disclose the claimed invention.
Gap fails to disclose a return line temperature sensor positioned in the refrigerant return line downstream of the first heat exchanger, wherein the return line temperature sensor is configured to measure refrigerant temperature in the refrigerant return line prior to reaching the refrigerant source.
Cai teaches that in the art of data center cooling that it is a known method to provide a return line temperature sensor (15) positioned in the refrigerant return line wherein the return line temperature sensor (15) is configured to measure refrigerant temperature in the refrigerant return line prior to reaching a refrigerant source (11). This is strong evidence that modifying Gao as claimed would produce predictable results (i.e., control the cooling power of the refrigerant source based on the refrigerant return temperature). Accordingly, it would have been obvious to a person having ordinary skill in the art at the time the invention was effectively filed, to modify Gao by Cai such that the return line included a return line temperature sensor positioned in the refrigerant return line downstream of the first heat exchanger (258), wherein the return line temperature sensor is configured to measure refrigerant temperature in the refrigerant return line prior to reaching the refrigerant source (250), since all claimed elements were known in the art, and one having ordinary skill in the art could have modified the prior art as claimed by known methods with no changes in their respective functions and the combination would have yielded a predictable result of controlling the refrigeration system based on the temperature of the refrigerant within the cooling loop.
Claim14-16 are rejected under 35 U.S.C. 103 as being unpatentable over Gao in view of US2015/0233967 to Thordarson et al., hereinafter referred to as Thordarson.
In reference to claim 14, Gao and Thordarson disclose the claimed invention.
Gao fails to disclose a step of monitoring refrigerant temperature before entering the supplemental heat exchanger and a step of monitoring ambient temperature at a location of the supplemental heat exchanger.
Thordarson teaches that it is a known method in the art of cooling systems to provide a step of monitoring refrigerant temperature (at T1) before entering a supplemental heat exchanger (105) and a step of monitoring ambient temperature 9at T0) at a location of the supplemental heat exchanger (105). Thordarson teaches that this method allows for adjusting the fan speed of the heat exchanger to meet cooling demands [0054-0055]. This is strong evidence that modifying Gao as claimed would produce predictable results. Accordingly, it would have been obvious to a person having ordinary skill in the art at the time the invention was effectively filed, to modify Gao by Thordarson such that the cooling method included a step of monitoring refrigerant temperature before entering the supplemental heat exchanger and a step of monitoring ambient temperature at a location of the supplemental heat exchanger, since all claimed elements were known in the art, and one having ordinary skill in the art could have modified the prior art as claimed by known methods with no changes in their respective functions and the combination would have yielded a predictable result of adjusting the fan speed of the heat exchanger to meet cooling demands.
In reference to claim 15, Gao and Thordarson disclose the claimed invention.
Gao as modified supra fail to disclose or teach a step of directing the refrigerant to flow through the supplemental heat exchanger if the refrigerant temperature is above the ambient temperature, thereby causing supplemental passive cooling of the refrigerant. However, it is noted that the recitation of, “to flow through the supplemental heat exchanger” is contingent upon the condition of “if the refrigerant temperature is above the ambient temperature”, which may never occur. The broadest reasonable interpretation of a method (or process) claim having contingent limitations requires only those steps that must be performed and does not include steps that are not required to be performed because the condition(s) precedent are not met, see MPEP 2111.04 (II). Accordingly, the Examiner does not need to present evidence of the obviousness of the method steps of claims that are not required to be performed under a broadest reasonable interpretation of the claim.
In reference to claim 16, Gao and Thordarson disclose the claimed invention.
Gao as modified supra fail to disclose or teach if the refrigerant temperature is at or lower than the ambient temperature, directing the refrigerant to flow outside the supplemental heat exchanger and through a supplemental bypass line prior to flowing to the refrigerant return line. However, it is noted that the recitation of, “directing the refrigerant to flow outside the supplemental heat exchanger and through a supplemental bypass line prior to flowing to the refrigerant return line” is contingent upon the condition of “if the refrigerant temperature is at or lower than the ambient temperature”, which may never occur. The broadest reasonable interpretation of a method (or process) claim having contingent limitations requires only those steps that must be performed and does not include steps that are not required to be performed because the condition(s) precedent are not met, see MPEP 2111.04 (II). Accordingly, the Examiner does not need to present evidence of the obviousness of the method steps of claims that are not required to be performed under a broadest reasonable interpretation of the claim.
Allowable Subject Matter
Claims 3-5 are 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.
Claim 19 is allowed.
Response to Arguments
The amendments to the claims have successfully overcome the rejections of claims 1-18 under 35 USC 112(b) and have therefore been withdrawn.
Applicant argues that Gao fails to disclose the supplemental heat exchanger between the first and second heat exchangers and the refrigerant return line. This is respectfully not found persuasive. For clarity, the examiner has defined the return line as represented by the bolded line in the annotated reference above with respect to claim 1. The claim requires the return line to begin where the lines of the first and second and supplemental heat exchangers merge and ends at the cooling entrance of the cooler (250). When the return line is defined as above, the supplemental heat exchanger (252) is indeed between heat exchanger (258) and the return line. There is nothing in the claims which would prevent the examiner from defining the return line as only the segment of refrigerant line bolded. Further, since this line is upstream of the cooling section of cooler (250), it is perfectly reasonable to consider this the return line. As such, the rejection of claim 1 as being anticipated by Gao is considered proper and remains.
The amendment to claim 3 requiring the supplemental bypass line being temperature neutral successfully reads over the prior art of Gao. As such, the rejection of claim 3 as being anticipated by Gao has been withdrawn and indicated as allowable.
Applicant argues on page 15 of the response that Gao’s language of “additionally or alternatively” means that the inlet of heat exchanger (252) receives external liquid from the return line. This is respectfully not found persuasive. When defining the return line to be where the refrigerant returning from the first, second, and supplemental heat exchanger merge (as specifically required by the claim), the refrigerant flows from heat exchanger (252) to the examiner defined return line.
Applicant argues that it is not reasonable to remap the return line such that the refrigerant return line exists after element 252. This is not found persuasive. There is nothing in the claims that would make it such that the return line could not be defined as above. This bolded portion of return line returns all of the refrigerant collected from the three heat exchangers and sends it to the cooling portion of the cooling source (250) as clearly evident in figure 5. There is nothing in the claims that would require the return line to be defined to begin before entering external cooling unit (248).
Applicant argues on page 17 of the response that Gao does not include a bypass mechanism. This is respectfully not found persuasive. In response to applicant's argument that the references fail to show certain features of the invention, it is noted that a bypass mechanism is not recited in the rejected claim(s). Claims 3, 15, and 16 simply require refrigerant to be directed towards the return line and not pass through the supplemental heat exchanger. There is no recitation of a valve to perform the bypassing function. 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).
Applicant argues beginning on page 17 of the response that Gao does not teach partially recirculating the refrigerant as required by claim 17. This is respectfully not found persuasive. The claim, given its broadest reasonable interpretation, claims the functionality in the alternative and not as requiring both functions. As claimed, if the prior art can do one or the other, the claimed conditions are met. Since Gao performs one of the claimed conditions, the claimed limitations are met by the prior art.
Applicant argues on page 19 of the response with respect to claim 16 that the condition is not hypothetical and must occur. This is respectfully not found persuasive. The claim specifically requires that if the refrigerant temperature is at or lower than the ambient temperature then the refrigerant is directed to flow through the supplemental bypass. There are many situations where the refrigerant temperature before entering the supplemental heat exchanger may never be lower than ambient. For example, in parts of the world where outdoor temperatures are high, or in situations where the cooling system is only operated where the temperature of the ambient environment are high and cooing demand is also high. In order for the step to be a part of normal operating conditions, the step must be required and necessarily happen during operation. Since there are conditions that may result in the conditional step never occurring, it is reasonable to interpret the limitation as being conditional and not required to be performed.
For at least these reasons, the rejections of claims 1-2 and 6-18 are considered proper and remain.
Conclusion
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CASSEY D BAUER whose telephone number is (571)270-7113. The examiner can normally be reached Mon-Thurs: 10AM-8PM (ET).
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/CASSEY D BAUER/Primary Examiner, Art Unit 3763
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