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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 12/16/2025 has been entered.
Status of Claims
This Office action is responsive to RCE filed on 12/16/2025.
Claims 1-4, 8-11 and 15-18 are amended.
Claims 7 and 14 are canceled.
Claims 21-22 are added.
Claims 1-6, 8-13 and 15-22 are pending and presented for examination.
Information Disclosure Statement
Examiner notes that an Information Disclosure Statement has not been filed by the Applicant as of the date of this office action.
Response to Arguments
Regarding the 35 U.S.C. §102 and §103 rejections
Applicant’s arguments with respect to claims 1-6, 8-13, and 15-20 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument. Applicant’s arguments are over amended features and are rejected over newly discovered prior art.
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 21-22 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.
Claims 21 and 22 both recite “the CDU to maintain a substantially constant pressure”. However, “substantially” is relative terminology. MPEP 2173.05(b).
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 1-3, 6, 8-10, 13, 15-17 and 20-22 are rejected under 35 U.S.C. 103 as being unpatentable over OTA (US20040221604A1) in view of BRUNSCHWILER (US20090218078A1) (hereinafter – “OTA-BRUNSCHWILER”).
Regarding claim 1
OTA teaches a method ([0001]), comprising:
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OTA, FIG. 4
detecting, a CDU and a node-specific pump positioned within a liquid coolant circulation loop of the liquid cooling system between the CDU and the computing node (FIG. 4 shows a liquid cooling system that includes a primary pump 41 within a cooling unit 52 (i.e., a CDU) and a node specific pump 23 positioned within a liquid coolant circuit loop of the liquid cooling system between the CDU 52 and the computing node/server module 62); and
responsive to detection of the condition, [0074]-[0076]: based on the detected temperature of the coolant flow quantity is controlled by the internal pump 23 so that the temperature of the heat-generating components 3 (heat-generating components 3 are inside of server module 62) is regulated, coolant is introduced to the heat-generating components by internal pump, coolant reaches the heat-generating component and cools the heat-generating component).
OTA is not relied on for a CDU comprising a controller.
However, BRUNSCHWILER in analogous art teaches:
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BRUNSCHWILER, Figure 13 – Examiner annotated
detecting, by a coolant distribution unit (CDU) of the liquid cooling system, for a computing node cooled by the liquid cooling system, a condition indicating increased heating within the computing node, wherein the liquid cooling system includes a primary pump and a node-specific pump positioned within a liquid coolant circulation loop of the liquid cooling system between the CDU and the computing node ([0001]: disclosure is directed to liquid cooling of data centers; Figure 13 shows computing nodes 22 (dashed lines from CPU within node 22 to controller 122 imply cooling nodes being in signal communication with controller) to be cooled with liquid coolant wherein the node has a node-specific pump (126, 128, 130) and the CDU comprises a controller and a primary pump (124); [0050]-[0053]: controller 122 is electrically coupled to monitor the cooling system 116, “Controller 122 is capable of converting the analog voltage or current level provided by sensors, such as temperature sensors for example, into a digital signal indicative of the heat generated by the computer system 22 […] In general, controller 122 accepts data from sensors, such as temperature sensors”); and
responsive to detection of the condition, controlling, by the CDU, the node-specific pump to increase a liquid flow rate of liquid coolant at the node-specific pump ([0049]: cooling system 116 includes coolant control devices 124, 126, 128, 130 that are capable of changing the amount of coolant flow through system, coolant control devices are capable of receiving a signal from controller 122 and changing the rate of flow of the coolant, in response to receiving the signal from the controller 122, “coolant control device 124 is arranged between the heat exchanger 118 and the computer systems 22. The coolant control device 124 allows the controller 122 to adjust the overall flow of the cooling system 116. The coolant control devices 126, 128, 130 are arranged to control the flow of coolant into the inlets of individual computer systems 22”; [0058]-[0059]: “During operation, the controller 122 receives signals required for normal operation and in particular for the control of the flow of coolant to the computer systems 22 […] controller 122 is further capable of operating each of the coolant control devices 124, 126, 128, 130 independently to accommodate the individual operational states of the computer systems 22”, accommodating the individual operational states of computer system implies a determined flow rate of cooling fluid to remove heat from the computing node such that the node can operate within a desired temperature range).
OTA and BRUNSCHWILER are analogous art to the claimed invention because they are from the same field of liquid cooling computing nodes. Before the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to apply the teachings of BRUNSCHWILER to the teachings of OTA such that BRUNSCHWILER’s controller could be used with OTA’s system for the purposes of centralizing the data processing so that a single computing node could be removed from a server rack without interrupting the computing and/or cooling operations of the other nodes.
Regarding claim 2
OTA-BRUNSCHWILER teaches the elements of claim 1 as outlined above.
BRUNSCHWILER also teaches:
detecting, for each of the plurality of comping nodes cooled by the liquid cooling system, one or more conditions indicating increased heating, wherein the liquid cooling system includes a plurality of node-specific pumps positioned in the liquid coolant circulation loop of the liquid cooling system between the primary pump and corresponding respectively to the plurality of computing nodes; and
responsive to detection of the one or more conditions, increasing cooling to the plurality of computing nodes by independently controlling the node-specific pumps corresponding to the plurality of computing nodes to increase liquid coolant flow rate at the node-specific pumps (BRUNSCHWILER, Figure 13 shows a plurality of computing nodes with a plurality of node-specific pumps in signal communication with a CDU such that the CDU can detect and respond to increased heating at one or more nodes, as outlined in the rejection to claim 1).
Regarding claim 3
OTA-BRUNSCHWILER teaches the elements of claim 1 as outlined above.
BRUNSCHWILER also teaches wherein detecting the condition indicating increased heating within the computing node comprises detecting an increase in temperature at one or more node-specific temperature sensors ([0050]-[0053]: controller 122 is electrically coupled to monitor the cooling system 116, “Controller 122 is capable of converting the analog voltage or current level provided by sensors, such as temperature sensors for example, into a digital signal indicative of the heat generated by the computer system 22 […] In general, controller 122 accepts data from sensors, such as temperature sensors”).
Regarding claim 6
OTA-BRUNSCHWILER teaches the elements of claim 1 as outlined above.
OTA also teaches wherein the liquid loop cooling system is configured to circulate the liquid coolant through a heat exchanger coupled to the computing node to absorb heat from the computing node ([0055] and FIG. 4: heat exchanger 50 is coupled to computing nodes).Regarding claim 8
BRUNSCHWILER teaches an apparatus comprising a coolant distribution unit (CDU) including: a primary pump configured to circulate liquid coolant through a liquid cooling system (Abstract: liquid cooling for data centers; Figure 13 (above) shows a CDU comprising a primary pump 124 configured to circulate liquid coolant through a liquid cooling system);
a computer processor ([0054]: controller 122 includes a processor);
a computer memory operatively coupled to the computer processor, the computer memory including computer program instructions that, when executed by the computer processor, cause the CDU to perform operations ([0054]: controller includes RAM, NVM, ROM; [0057]: controller includes operation control methods embodied in application code, application code also includes program instructions for causing processor to execute control methods).
The remaining limitations of claim 8 recite subject material similar to claim 1, and are rejected as per such.
Regarding claim 9
OTA-BRUNSCHWILER teaches the elements of claim 8 as outlined above.
The remaining limitations of claim 9 recite subject material similar to claim 2, and are rejected as per such.
Regarding claim 10
OTA-BRUNSCHWILER teaches the elements of claim 8 as outlined above.
The remaining limitations of claim 10 recite subject material similar to claim 3, and are rejected as per such.
Regarding claim 13
OTA-BRUNSCHWILER teaches the elements of claim 8 as outlined above.
OTA also teaches wherein the liquid coolant flows in a closed circulation loop between the primary pump and the node (FIG. 4 shows liquid coolant leaving primary pump 41 to go into downstream pipe 30 and then into cooling nodes before returning to primary pump via upstream pipe 31).
Regarding claim 15
BRUNSCHWILER teaches a computer program comprising a computer readable medium storing computer program instructions that, when executed by a processor of a coolant distribution unit (CDU) of a liquid cooling system, cause the CDU to perform operations (Abstract: liquid cooling for data centers; [0054]-[0056]: controller processor coupled to non-volatile memory (NVM) device, NVM device stores application code which comprises program instructions for causing processor to execute control methods).
The remaining limitations of claim 15 recite subject material similar to claim 1, and are rejected as per such.
Regarding claim 16
OTA-BRUNSCHWILER teaches the elements of claim 15 as outlined above.
The remaining limitations of claim 16 recite subject material similar to claim 2, and are rejected as per such.
Regarding claim 17
OTA-BRUNSCHWILER teaches the elements of claim 15 as outlined above.
The remaining limitations of claim 17 recite subject material similar to claim 3, and are rejected as per such.
Regarding claim 20
OTA-BRUNSCHWILER teaches the elements of claim 15 as outlined above.
BRUNSCHWILER also teaches wherein the computer readable medium comprises a storage medium ([0056]: application code stored in NVM device).
Regarding claim 21
OTA-BRUNSCHWILER teaches the elements of claim 1 as outlined above.
OTA teaches that a change in flow quantity through cooling nodes causes a change in pressure, which OTA compensates for through the use of a bypass valves ([0043]-[0047]).
BRUNSCHWILER teaches a CDU comprising a controller configured to receive data from sensors distributed throughout the system, and wherein the controller is configured to operate the primary pump and the node pumps.
Before the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to apply the teachings of OTA to the teachings of BRUNSCHWILER such that BRUNSCHWILER’s controller would adjust the operation of the primary pump within the CDU to maintain substantially constant pressure in the liquid coolant circulation loop for the purposes of providing positive pressure of the liquid coolant at the node-specific pumps to prevent pump cavitation.
Regarding claim 22
OTA-BRUNSCHWILER teaches the elements of claim 8 as outlined above.
The remaining limitations of claim 22 recite subject material similar to claim 21, and are rejected as per such.
Claims 4-5, 11-12 and 18-19 are rejected under 35 U.S.C. 103 as being unpatentable over OTA-BRUNSCHWILER in view of BOWER (US20120123595A1) (hereinafter – “OTA-BRUNSCHWILER-BOWER”).
Regarding claim 4
OTA-BRUNSCHWILER teaches the elements of claim 1 as outlined above.
OTA-BRUNSCHWILER are not relied on for wherein detecting the condition indicating increased heating within the computing node comprises detecting an increase in node-specific power consumption.
However, BOWER in analogous art teaches this claim limitation ([0032]: determining the temperature of each monitored component may include determining whether a processor is in a turbo mode, turbo mode is a mode in which the processor is overclocked).
BOWER is analogous art to the claimed invention because they are from the same field of thermal management of computing systems. Before the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to apply the teachings of BOWER to the teachings of OTA-BRUNSCHWILER such that BOWER’s detection of an increase in node-specific power consumption could be used with OTA-BRUNSCHWILER’s node-specific cooling system for the purposes of supplying the node with a coolant liquid before the node overheats.
Regarding claim 5
OTA-BRUNSCHWILER-BOWER teaches the elements of claim 4 as outlined above.
BOWER also teaches wherein detecting an increase in node-specific power consumption comprises detecting an increase in workload in the computing node ([0032]: determining the temperature of each monitored component may include determining whether a processor is in a state with a high current or planned work load).
Regarding claim 11
OTA-BRUNSCHWILER teaches the elements of claim 8 as outlined above.
The remaining limitations of claim 11 recite subject material similar to claim 4, and are rejected as per such.
Regarding claim 12
OTA-BRUNSCHWILER-BOWER teaches the elements of claim 11 as outlined above.
The remaining limitations of claim 12 recite subject material similar to claim 5, and are rejected as per such.
Regarding claim 18
OTA-BRUNSCHWILER teaches the elements of claim 15 as outlined above.
The remaining limitations of claim 18 recite subject material similar to claim 4, and are rejected as per such.
Regarding claim 19
OTA-BRUNSCHWILER-BOWER teaches the elements of claim 18 as outlined above.
The remaining limitations of claim 19 recite subject material similar to claim 5, and are rejected as per such.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
LASMNS (“Lenovo ThinkSystem SD650 Direct Water Cooled Server Walkthrough”, published 21 October 2019, retrieved from https://www.youtube.com/watch?v=Alsfq9CjdHg, retrieved on 2/2/2026) teaches parallel node cooling with a CDU.
Asetek (“Distributed Pumping: The “Swiss Army Knife” of Liquid Cooling”, 21 November 2016, retrieved from https://www.asetek.com/blogs/distributed-pumping-the-swiss-army-knife-of-liquid-cooling/, retrieved on 2/2/2026) teaches pumping at computing nodes to be cooled allows for very low pressure to be used, mitigating failure risk of the computer node.
Coles, H., et al. (“Direct Liquid Cooling for Electronic Equipment”, March 2014, retrieved from https://datacenters.lbl.gov/sites/default/files/direct_liquid_cooling.pdf, retrieved on 2/2/2026) teaches parallel node cooling.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Michael V Farina whose telephone number is (571)272-4982. The examiner can normally be reached Mon-Thu 8:00-6:00 EST.
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/M.V.F./Examiner, Art Unit 2115
/KAMINI S SHAH/Supervisory Patent Examiner, Art Unit 2115