Prosecution Insights
Last updated: April 19, 2026
Application No. 18/355,919

INTERNAL PERFORMANCE MONITORING FOR WATER FILTER

Final Rejection §103
Filed
Jul 20, 2023
Examiner
GURTOWSKI, RICHARD C
Art Unit
1773
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Haier US Appliance Solutions Inc.
OA Round
2 (Final)
72%
Grant Probability
Favorable
3-4
OA Rounds
2y 10m
To Grant
99%
With Interview

Examiner Intelligence

Grants 72% — above average
72%
Career Allow Rate
541 granted / 755 resolved
+6.7% vs TC avg
Strong +39% interview lift
Without
With
+39.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
35 currently pending
Career history
790
Total Applications
across all art units

Statute-Specific Performance

§101
2.4%
-37.6% vs TC avg
§103
43.7%
+3.7% vs TC avg
§102
19.8%
-20.2% vs TC avg
§112
29.3%
-10.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 755 resolved cases

Office Action

§103
DETAILED ACTION For this Office action, Claims 1-20 are pending. 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 § 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. The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows: 1. Determining the scope and contents of the prior art. 2. Ascertaining the differences between the prior art and the claims at issue. 3. Resolving the level of ordinary skill in the pertinent art. 4. Considering objective evidence present in the application indicating obviousness or nonobviousness. 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. Claims 1-20 are rejected under 35 U.S.C. 103 as being unpatentable over Skwiot, US Pat Pub. 2006/0144765, in view of Nyberg et al. (herein referred to as “Nyberg”, US Pat Pub. 2007/0108056). Regarding instant Claim 1, Skwiot discloses a water filter assembly for a host appliance (Abstract; filtration assembly for water dispenser), the water filter assembly comprising: a filter housing defining a filter chamber, a feed water inlet, and a treated water outlet (Figure 1; Paragraph [0015]; cartridge filter 11 is chamber with inlet associated with supply flow 15 and outlet associated with permeate flow 17); a filter element received within the filter chamber defining a feed water chamber and a treated water chamber (Figure 1; Paragraph [0015]; filtration media 13); a feed water electrode disposed on the feed side (Figure 1; Paragraph [0022]; Paragraph [0040]; Paragraph [0042]; first sensor probe 21, see that “gold-plated brass” and “compatible electrical properties” provides evidence of probes being electrodes); a treated water electrode disposed on the treated side (Figure 1; Paragraph [0022]; Paragraph [0040]; Paragraph [0042]; second sensor probe 23); a common electrode in electrical communication with the feed water electrode and the treated water electrode (Figure 2B; Paragraph [0042]; interfaces 46 and 47 at Pin 11 are common junction of probes 21 and 23); an electric power supply in electrical communication with the feed water electrode, the treated water electrode and the common electrode (Figure 1; Paragraph [0014]; power supply 8); a sensing system electrically coupled to the feed water electrode, the treated water electrode and the common electrode (Figure 1; Paragraph [0016]; sensor monitor circuit with sensor interfaces for probes 21 and 23); a controller electrically coupled to the electric power supply and the sensing system (Figure 2A; Paragraph [0016]; microcontroller 24), wherein the controller is configured to: receive a first signal from sensing system that is proportional to a water quality parameter of a content of the feed water chamber (Figure 2B; Paragraph [0022]; Paragraph [0040]; Paragraph [0041]; Paragraph [0042]; probe 21 sends signal via voltage/current wherein said voltage/current is proportional to dissolved solids in water); receive a second signal from the sensing system that is proportional to a water quality parameter of a content of the treated water chamber (Figure 2B; Paragraph [0022]; Paragraph [0040]; Paragraph [0041]; Paragraph [0042]; probe 23 sends signal via voltage/current wherein said voltage/current is proportional to dissolved solids in water); determine a filter status based on the first and second signals (Abstract; Figure 1; Figure 2B; Paragraph [0018]; Paragraphs [0045]-[0049]; microcontroller determines status based on difference/comparison/ratios and provides status via indicator 7c). However, the references are silent on the feed water electrode and the treated water electrode being in their respective water chambers. Nyberg discloses an electrochemical ion exchange treatment of fluids in the same field of endeavor as the instant application, as it solves the mutual problem of providing signals to a microcontroller to determine the status of fluid being treated (Abstract; Paragraph [0077]). Nyberg further discloses that sensors/electrodes may be placed anywhere within relation to a cartridge, such as the inlets and the outlets of said cartridge, in order to accurately measure the parameter at that location (Figure 1; Paragraph [0046]; Paragraph [0077]; see conductivity sensor 160 that can be put in both locations). It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the location of the feed water and treated water electrodes of Skwiot to be in their respective chambers as taught by Nyberg because Nyberg discloses the location of electrodes/sensors may be adjusted to accurately measure the parameter at the locations of said electrodes/sensors (Nyberg, Paragraph [0046]; Paragraph [0077]). Regarding instant Claim 2, Claim 1, upon which Claim 2 is dependent, has been rejected above. Skwiot further discloses wherein the controller drives the electric power supply to provide a first controlled voltage between the feed water electrode and the common electrode and a second controlled voltage between the treated water electrode and the common electrode (Paragraph [0026]; Paragraphs [0040]-[0042]; separate voltages are sent to probes 21 and 23 from microcontroller 24). Regarding instant Claim 3, Claim 2, upon which Claim 3 is dependent, has been rejected above. Skwiot further discloses wherein the first controlled voltage and the second controlled voltage are different in at least magnitude (Paragraphs [0040—[0042]; magnitude of voltage is at least switched to reverse voltage via pins 3 and 10). Regarding instant Claim 4, Claim 2, upon which Claim 4 is dependent, has been rejected above. Skwiot further discloses wherein the first signal is an electrical current proportional to a conductivity of the content of the feed water chamber (Paragraph [0040]; current flow proportional to level of TDS/conductivity of the water at both probes). Regarding instant Claim 5, Claim 2, upon which Claim 5 is dependent, has been rejected above. Skwiot further discloses wherein the second signal is an electrical current proportional to a conductivity of the treated water chamber (Paragraph [0026]; Paragraph [0040]; current flow proportional to level of TDS/conductivity of the water at both probes; see also plurality of measurements that are made). Regarding instant Claim 6, Claim 1, upon which Claim 6 is dependent, has been rejected above. Skwiot further discloses the controller drives the electric power supply to provide a first controlled current to the feed water electrode and a second controlled current to the treated water electrode (Paragraph [0006]; Paragraph [0026]; alternating current applied and voltage measured). Regarding instant Claim 7, Claim 6, upon which Claim 7 is dependent, has been rejected above. Skwiot further discloses wherein the first controlled current and the second controlled current are different from each other in at least one of magnitude and frequency (Paragraphs [0040—[0042]; frequency of current [alternating] is at least switched to reverse voltage via pins 3 and 10). Regarding instant Claim 8, Claim 6, upon which Claim 8 is dependent, has been rejected above. Skwiot further discloses wherein the first signal is a voltage proportional to a conductivity of a content of the feed water chamber (Paragraph [0006]; Paragraph [0026]; Paragraph [0042]; see that detected current may be proportional to conductivity for both sensors/electrodes). Regarding instant Claim 9, Claim 6, upon which Claim 9 is dependent, has been rejected above. Skwiot further discloses wherein the second signal is a voltage proportional to a conductivity of a content of the treated water chamber (Paragraph [0006]; Paragraph [0026]; Paragraph [0042]; see that detected current may be proportional to conductivity for both sensors/electrodes). Regarding instant Claim 10, Claim 1, upon which Claim 10 is dependent, has been rejected above. Skwiot discloses that the filer element may comprise multiple filter media (Paragraph [0015]; combination of media may be used) and the electrodes may be made of any material having electrically compatible properties (Paragraph [0022]), but is silent on an electrically conductive filter media. However, Nyberg discloses an electrically conductive filter media (Figure 10; Paragraph [0122]; Paragraph [0149]; Paragraph [0151]; carbon filter) and that carbon may be used as an erosion resistant electrode (Paragraph [0050]; Claim 97). It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the filtration media of Skwiot to include carbon as taught by Nyberg because Nyberg discloses carbon is an erosion resistant electrode, wherein the conductive material can be part of the common electrode of Skwiot (Nyberg, Paragraph [0122]; Paragraph [0149]; Paragraph [0151]). Regarding instant Claim 11, Claim 10, upon which Claim 11 is dependent, has been rejected above. The combined references further disclose wherein the conductive filter media comprises carbon or activated carbon (Nyberg, Paragraph [0122]; Paragraph [0149]; Paragraph [0151]; at least carbon). Regarding instant Claim 12, Claim 1, upon which Claim 12 is dependent, has been rejected above. Skwiot further discloses wherein the controller is in operative communication with the host appliance (Figure 1; Paragraph [0014]; Paragraph [0016]; microcontroller 24 in communication with dispenser 6). Regarding instant Claim 13, Claim 1, upon which Claim 13 is dependent, has been rejected above. Skwiot further discloses wherein the controller causes a display on a control panel to provide an indicator of a remaining useful life of the filter element based on the first signal and the second signal (Figure 1; Paragraph [0014]; status indicator 7). Regarding instant Claim 14, Skwiot discloses a method of operating a water filter assembly (Abstract; method of operating a filtration assembly for water dispenser) comprising a filter housing defining a filter chamber (Figure 1; Paragraph [0015]; cartridge filter 11 is chamber with inlet associated with supply flow 15 and outlet associated with permeate flow 17), a filter element received within the filter chamber defining a feed water chamber and a treated water chamber (Figure 1; Paragraph [0015]; filtration media 13), a feed water electrode disposed on the feed side (Figure 1; Paragraph [0022]; Paragraph [0040]; Paragraph [0042]; first sensor probe 21, see that “gold-plated brass” and “compatible electrical properties” provides evidence of probes being electrodes), a treated water electrode disposed on the treated side (Figure 1; Paragraph [0022]; Paragraph [0040]; Paragraph [0042]; second sensor probe 23), a common electrode in electrical communication with the feed water electrode and the treated water electrode (Figure 2B; Paragraph [0042]; interfaces 46 and 47 at Pin 11 are common junction of probes 21 and 23), an electric power supply in electrical communication with the feed water electrode, the treated water electrode and the common electrode (Figure 1; Paragraph [0014]; power supply 8), a sensing system comprising a first electrical measurement sensor electrically coupled to the feed water electrode and the common electrode and a second electrical measurement sensor electrically coupled to the treated water electrode and the common electrode (Figure 1; Paragraph [0016]; sensor monitor circuit with sensor interfaces for probes 21 and 23) and a controller electrically coupled to the electric power supply and the sensing system (Figure 2A; Paragraph [0016]; microcontroller 24), the method comprising: receiving at the controller a first signal from the first electrical measurement sensor that is proportional to a water quality parameter of a content of the feed water chamber (Figure 2B; Paragraph [0022]; Paragraph [0040]; Paragraph [0041]; Paragraph [0042]; probe 21 sends signal via voltage/current wherein said voltage/current is proportional to dissolved solids in water); receiving at the controller a second signal from the sensing system that is proportional to a water quality parameter of a content of the treated water chamber (Figure 2B; Paragraph [0022]; Paragraph [0040]; Paragraph [0041]; Paragraph [0042]; probe 23 sends signal via voltage/current wherein said voltage/current is proportional to dissolved solids in water); determining a conductivity of the content of the feed water chamber (Paragraph [0040]; current flow proportional to level of TDS/conductivity of the water at both probes); determining a conductivity of the content of the treated water chamber (Paragraph [0040]; current flow proportional to level of TDS/conductivity of the water at both probes); determining a status of the filter element based on the conductivity of the content of the feed water chamber and the conductivity of the content of the treated water chamber; and displaying a status of the filter element on a display (Abstract; Figure 1; Figure 2B; Paragraph [0018]; Paragraphs [0045]-[0049]; microcontroller determines status based on difference/comparison/ratios and provides status via indicator 7c). However, the references are silent on the feed water electrode and the treated water electrode being in their respective water chambers. Nyberg discloses an electrochemical ion exchange treatment of fluids in the same field of endeavor as the instant application, as it solves the mutual problem of providing signals to a microcontroller to determine the status of fluid being treated (Abstract; Paragraph [0077]). Nyberg further discloses that sensors/electrodes may be placed anywhere within relation to a cartridge, such as the inlets and the outlets of said cartridge, in order to accurately measure the parameter at that location (Figure 1; Paragraph [0046]; Paragraph [0077]; see conductivity sensor 160 that can be put in both locations). It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the location of the feed water and treated water electrodes of Skwiot to be in their respective chambers as taught by Nyberg because Nyberg discloses the location of electrodes/sensors may be adjusted to accurately measure the parameter at the locations of said electrodes/sensors (Nyberg, Paragraph [0046]; Paragraph [0077]). Regarding instant Claim 15, Claim 14, upon which Claim 14 is dependent, has been rejected above. Skwiot further discloses wherein determining the status of the filter element comprises: calculating a mathematical change between the conductivity of the content of the feed water chamber and the conductivity of the content of the treated water (Paragraphs [0042]-[0044]; see TDS rejection ratio that is calculated from sensor outputs); establishing a predetermined threshold value for the mathematical change between the conductivity of the content of the feed water chamber and the conductivity of the content of the treated water chamber (Paragraph [0044]; see reference voltage used for comparisons); and comparing the mathematical change to the predetermined threshold (Paragraph [0044]; ratio is compared to voltage threshold). Regarding instant Claim 16, Claim 15, upon which Claim 16 is dependent, has been rejected above. Skwiot further discloses wherein: the mathematical change is a percentage change (Paragraph [0044]; ratio between unfiltered and filtered water); and displaying the status comprises signaling a filter failure if the percentage change falls below the predetermined threshold (Paragraph [0018]; Paragraph [0044]; Paragraph [0061]; consecutive bad readings leads to signaling filter failure via indicator 7c). Regarding instant Claim 17, Claim 16, upon which Claim 17 is dependent, has been rejected above. Skwiot further discloses wherein the predetermined threshold value is a dynamic threshold value depending on the determined conductivity of the content of the feed water chamber (Paragraphs [0042]-[0044]; threshold is a ratio that would be dependent on the reading of the feed water). Regarding instant Claim 18, Claim 17, upon which Claim 18 is dependent, has been rejected above. Skwiot further discloses wherein the dynamic threshold value is predetermined for a plurality of ranges of conductivity of the content of the feed water chamber such that the predetermined threshold changes with each range of conductivity (Paragraphs [0042]-[0044]; ratio and accepted value of permeate/treated chamber adjusts with measured value of feed). Regarding instant Claim 19, Claim 14, upon which Claim 19 is dependent, has been rejected above. Skwiot further discloses wherein, during a period of time of predetermined duration following an initial in-service operation (Paragraph [0041]; anytime after start of port toggling loop), determining the status of the filter element comprises: determining a mathematical representation of the conductivity of the content of the feed water chamber for the period of time (Paragraph [0026]; Paragraph [0042]; internal reference voltage for feed from comparator provides reference threshold/mathematical representation); determining a mathematical representation of the conductivity of the content of the treated water chamber for the period of time (Paragraph [0026]; Paragraph [0042]; internal reference voltage for treated water/permeate from comparator provides reference threshold/mathematical representation); calculating a percentage change between the mathematical representation of the content of the feed water chamber and the mathematical representation of the conductivity of the content of the treated water chamber for the period of time (Paragraph [0026]; Paragraphs [0040]-[0044]; reference voltage is calculated using comparator based on these values); establishing a threshold value based on the calculated percentage change for the period of time (Paragraphs [0040]-[0044]; reference voltage); calculating a present conductivity of the content of the feed water chamber (Paragraphs [0040]-[0044]; receiving of input from probe 21 regarding TDS); calculating a present conductivity of the content of the treated water chamber (Paragraphs [0040]-[0044]; receiving of input from probe 23 regarding TDS); calculating a present percentage change between the present conductivity of the content of the feed water chamber and the present conductivity of the content of the feed water chamber and the present conductivity of the treated water chamber (Paragraphs [0040]-[0044]; ratio of TDS calculated); comparing the present percent change to the established threshold for the period of time (Paragraphs [0040]-[0044]; calculated TDS ratio is compared to reference voltage); and displaying a status signaling a filter failure if the percentage falls below the established threshold ( Regarding instant Claim 20, Skwiot discloses a water filter assembly for a host appliance (Abstract; filtration assembly for water dispenser), the water filter assembly comprising: a filter housing defining a filter chamber, a feed water inlet, and a treated water outlet (Figure 1; Paragraph [0015]; cartridge filter 11 is chamber with inlet associated with supply flow 15 and outlet associated with permeate flow 17); a filter element received within the filter chamber defining a feed water chamber and a treated water chamber (Figure 1; Paragraph [0015]; filtration media 13); a feed water sensor array disposed on the feed side (Figure 1; Paragraph [0015]; Paragraph [0022]; Paragraph [0040]; Paragraph [0042]; first sensor probe 21 and plurality of other potential sensors such as pH and flow); a treated water sensor array disposed on the treated side (Figure 1; Paragraph [0015]; Paragraph [0022]; Paragraph [0040]; Paragraph [0042]; second sensor probe 23 and plurality of other sensors such as pH and flow); an electric power supply in electrical communication with the feed water sensor array and the treated water sensor array (Figure 1; Paragraph [0014]; power supply 8); a sensing system electrically coupled to the feed water sensor array and the treated water sensor array (Figure 1; Paragraph [0016]; sensor monitor circuit with sensor interfaces for probes 21 and 23); a controller electrically coupled to the electric power supply and the sensing system (Figure 2A; Paragraph [0016]; microcontroller 24), wherein the controller is configured to: receive a first signal from sensing system that is proportional to a water quality parameter of a content of the feed water chamber (Figure 2B; Paragraph [0022]; Paragraph [0040]; Paragraph [0041]; Paragraph [0042]; probe 21 sends signal via voltage/current wherein said voltage/current is proportional to dissolved solids in water); receive a second signal from the sensing system that is proportional to a water quality parameter of a content of the treated water chamber (Figure 2B; Paragraph [0022]; Paragraph [0040]; Paragraph [0041]; Paragraph [0042]; probe 23 sends signal via voltage/current wherein said voltage/current is proportional to dissolved solids in water); determine a filter status based on the first and second signals (Abstract; Figure 1; Figure 2B; Paragraph [0018]; Paragraphs [0045]-[0049]; microcontroller determines status based on difference/comparison/ratios and provides status via indicator 7c). However, the references are silent on the feed water sensor array and the treated water sensor array being in their respective water chambers. Nyberg discloses an electrochemical ion exchange treatment of fluids in the same field of endeavor as the instant application, as it solves the mutual problem of providing signals to a microcontroller to determine the status of fluid being treated (Abstract; Paragraph [0077]). Nyberg further discloses that sensors/electrodes may be placed anywhere within relation to a cartridge, such as the inlets and the outlets of said cartridge, in order to accurately measure the parameter at that location (Figure 1; Paragraph [0046]; Paragraph [0077]; see conductivity sensor 160 that can be put in both locations). It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the location of the feed water and treated water electrodes of Skwiot to be in their respective chambers as taught by Nyberg because Nyberg discloses the location of electrodes/sensors may be adjusted to accurately measure the parameter at the locations of said electrodes/sensors (Nyberg, Paragraph [0046]; Paragraph [0077]). Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to RICHARD C GURTOWSKI whose telephone number is (571)272-3189. The examiner can normally be reached 9:00 am-5:30pm MT. 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, Benjamin Lebron can be reached at (571) 272-0475. 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. /RICHARD C GURTOWSKI/Primary Examiner, Art Unit 1773 01/09/2026
Read full office action

Prosecution Timeline

Jul 20, 2023
Application Filed
Jan 09, 2026
Non-Final Rejection — §103
Feb 26, 2026
Interview Requested
Mar 04, 2026
Applicant Interview (Telephonic)
Mar 04, 2026
Examiner Interview Summary
Mar 11, 2026
Response Filed
Apr 09, 2026
Final Rejection — §103 (current)

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Expected OA Rounds
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