DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 09/14/2026 has been entered.
Response to Arguments
Applicant's arguments filed 09/17/2026 have been fully considered but they are not persuasive.
In response to Applicant’s arguments stating that modifying protrusion of Hishikawa would change its basic principle of operation, the Examiner respectfully disagrees. As stated by Applicant, Hishikawa explicitly states that the purpose of the protrusion is to suppress rapid change in the flow rate of gas but does not complete stop the flow of gas at a small opening degrees of the turning plate, which is shown in Fig. 19 of Hishikawa showing 51 being only slightly opened and gas flowing past 59 through a reduced open area. Applicant’s specification provides the same function for the deflector rib and states “Under the condition that the turning plate 20 opens the first gas passage 12a and the first airflow passage 11 a with a small opening degree, the flow rate of the gas is too large, and the air-fuel ratio cannot meet the design requirements, and the deflector rib 22 can reduce the flow rate of the gas in the corresponding first gas passage 12a and reduce the gas flow, so that the mixed gas reaches a preset air-fuel ratio” (see ¶ [0047] of the specification). This quoted passage is the only statement made within the specification about the function of the deflector rib. No statement is made as to why the arc shape of the deflector rib improves or helps this function in any way. Applicant’s statements of the criticality of the arc shape within the remarks presented on 09/14/2026 are not drawn from the specification and further do not differentiate how Hishikawa would perform any differently from the claimed device with either shape. Further, Applicant’s presented data only shows a comparison between a turning plate with no deflector rib and one with the claimed deflector rib and therefore doesn’t provide any further evidence to the benefit of the arc shape over the shape of Hishikawa. In fact the protrusion of Hishikawa with its shape shown in Fig. 18 would appear to present the same data, as its explicit purpose is to reduce the gas flow rate at low opening steps. Therefore, the rationale of design choice for the arc shape of the deflector rib is maintained.
In response to Applicant’s arguments regarding the use of Kim, the Examiner disagrees. Kim clearly shows 211 as smaller than 221 in Fig. 4. Gas and air flow through the chamber 320, in which 221 is positioned, is regulated by 420. Therefore, Kim teaches of providing a larger gas passage for the gas passage that is in the chamber that is regulated via some form of damper or valve.
In response to applicant's argument that the examiner has combined an excessive number of references, reliance on a large number of references in a rejection does not, without more, weigh against the obviousness of the claimed invention. See In re Gorman, 933 F.2d 982, 18 USPQ2d 1885 (Fed. Cir. 1991). The Examiner clearly states “the apparent reason to combine the known elements in the fashion claimed” within the rejection and Applicant does not provide any evidence as to how the Examiner has failed to do so.
Drawings
The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the “arc shape” and “arc-shaped opening” in claim 1 and the “middle part and two end portions, and a height of the deflector rib gradually decreases from the middle part toward the two ends” in claims 21 and 22 must be shown or the feature(s) canceled from the claim(s). No new matter should be entered.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
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) 1-9 and 12-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Liu (CN 210485713 U) in view of Schmidt (DE 102012009628 A1), Hishikawa (US 20210291127 A1) and Kim (US 20150086931 A1).
Regarding claim 1, Liu teaches of:
A premixing device for a water heater, the premixing device comprising:
a housing (Fig. 1, 100 has a housing 10), in which a first airflow passage (Fig. 9, 1121), a second airflow passage (Fig. 9, 1122), a first gas passage (Fig. 9, 1111), and a second gas passage are formed (Fig. 9, 1112); and
a turning plate rotatably disposed on the housing to adjust an opening degree of the first gas passage and an opening degree of the first airflow passage (Fig. 6, 20; ¶ [0059], “Thus, valve 20 can control the amount of gas and air entering the gas flow channel 11 by adjusting the normally closed gas flow channel 1111 and/or the normally closed air flow channel 1121”)
wherein the first gas passage is surrounded by the first airflow passage (1111 is surrounded by 1121)
Liu fails to explicitly teach:
an air guide hole directly opposite to the first airflow passage being formed on the turning plate; and
a deflector rib directly opposite to the first gas passage, wherein the deflector rib is disposed on the turning plate, and the deflector rib has an arc shape, and comprises an arc-shaped opening facing a pivot shaft of the turning plate
wherein a sectional area of the second gas passage is smaller than a sectional area of the first gas passage.
Schmidt teaches of:
an air guide hole directly opposite to the first airflow passage being formed on the turning plate (Fig. 4, 9 has air guide holes 13)
The primary reference can be modified to meet this/these limitation(s) as follows:
add an air guide hole to the turning plate 20 of Liu positioned in a way so that when 20 is closed air can still flow through the air guide hole from the first flow channel 1121
A person of ordinary skill in the art prior to the effective filing date of the claimed invention would have been motivated to make the above modification(s) because:
Since the change in flow rate of air to the amount of fuel pulled into the venturi due to a pressure difference is not 1:1, at low combustion levels where the turning plate is closed so that both the first air and gas channels are closed and the second air and gas channels are opened the air-gas ratio drops so that the mixture is rich in gas. Therefore, by adding the air guide holes to the turning plate some air can still flow through the turning plate via the air guide holes, maintaining an oxygen rich combustion gas mixture and resulting in reduced NOx formation (Schmidt, Fig. 5, the Y-axis represents air-gas ratio, a higher number means more air compared to gas, the X-axis represented the power output of the burner, line 15 represents a valve with no air guide holes, at low power levels there is a drop in the ratio resulting in an increase in pollutant formation, line 16 represents the valve of Fig. 4 with air guide holes, at low power levels the drop in the ratio is reduced and therefore pollutant formation is reduced)
Hishikawa teaches of:
A deflector rib (Fig. 18, 59) directly opposite to the first gas passage (59 is opposite s1), wherein the deflector rib is disposed on the turning plate (59 is disposed on 51)
The combined teachings can be modified to meet this/these limitation(s) as follows:
Add a deflector rib to 20 of Liu so that it extends into 1111
A person of ordinary skill in the art prior to the effective filing date of the claimed invention would have been motivated to make the above modification(s) because:
In a situation where the turning plate only opens a small amount, the gas passage would not be completely opened due to the insertion of the deflector rib, this would prevent a large increase in gas flow with a disproportionate increase in airflow
Hishikawa does not explicitly teach that the deflector rib is arc shaped and has an arc-shaped opening facing the pivot shaft, however at the time the invention was made it would have been obvious mater of design choice to a person of ordinary skill in the art to have made the deflector rib an arc shape comprising a middle part and two end portions, and a height of the deflector rib gradually decreases from the middle part toward the two ends instead of the angled rectangular shape shown, because applicant has not disclosed that the arc shape provides an advantage, is used for particular purpose or solves a stated problem. One of ordinary skill in the art would have expected the Applicant' s invention to perform equally well with an arc or rectangular shape, because both shapes performs the function of reducing the gas flow rate at low openings of the turning plate through the first gas passage equally well (MPEP 2144.04 IV B)
Kim teaches of:
wherein a sectional area of the second gas passage is smaller than a sectional area of the first gas passage (Figs. 3-4, 211 is smaller than 221)
The combined teachings can be modified to meet this/these limitation(s) as follows:
modify the sectional area of the outlet second gas passage to be smaller than the sectional area of the outlet of the first gas passage
A person of ordinary skill in the art prior to the effective filing date of the claimed invention would have been motivated to make the above modification(s) because:
modifying the sizes of the gas passages would turn the second gas and air passage into a low load portion of the dual venturi of Liu and the first gas and air passage into a high load portion of the dual venturi that can be adjusted through the control of the turning plate, this would improve the turn down ratio of the premixing device (Kim, ¶ [0007], “In particular, when the burner operates in low heating and hot-water load region, the combustion device may be frequently turned on/off, and thus the combustion state may be unstable. As a result, a variation in a temperature control increases to deteriorate durability of the device. Therefore, methods for improving the TDR of the burner that are applied to combustion devices have been proposed”; ¶ [0053], “On the other hand, in the relatively low-output load region, the premixing may be performed in only the first premixing chambers 310, but not be performed in the second premixing chamber 320 to improve the turndown ratio (TDR)”)
Regarding claim 3, the combined teachings teach of the premixing device for the water heater according to claim 1, and the combined teachings further teach:
wherein:
a first support portion is disposed in the housing, the first airflow passage being formed in the first support portion; and
a second support portion is disposed in the first airflow passage, the first gas passage being formed in the second support portion (See annotated Fig. 11 of Liu below, the first airflow passage 1121 has a first support portion and within the first airflow passage is the second support portion which has the first gas passage 1111 within it).
Regarding claim 4, the combined teachings teach of the premixing device for the water heater according to claim 3, and the combined teachings further teach:
wherein:
an end surface of a free end of the second support portion and an end surface of a free end of the first support portion are disposed obliquely (see annotated Fig. 6 of Liu below, the free end of the first and second support portions are disposed obliquely); and
the turning plate is rotatable to abut against the end surface of the second support portion and/or the end surface of the first support portion (see annotated Fig. 6 of Liu below, the turning plate 20 abuts the end supports of the first and second support portions).
Regarding claim 5, the combined teachings teach of the premixing device for the water heater according to claim 4, and the combined teachings further teach:
wherein the first support portion is inclined in an air flow direction from top to bottom (See both annotated Fig. 6 and 11 of Liu below, the first support portion is inclined from top to bottom in an airflow direction)
Regarding claim 6, the combined teachings teach of the premixing device for the water heater according to claim 4, and the combined teachings further teach:
wherein:
a third support portion is disposed in the housing, a second airflow passage being formed in the third support portion (see annotated Fig. 11 of Liu below, a second airflow passage 1122 is within the third support portion);
a fourth support portion is disposed in the second airflow passage, a second gas passage being formed in the fourth support portion (see annotated Fig. 11 of Liu below, the fourth support portion is within the second airflow passage 1122 and the second gas passage 1112 is within the fourth support portion); and
an end surface of the third support portion protrudes relative to the end surface of the first support portion (see annotated Fig. 11 of Liu below, the third support portion protrudes relative to the first support portion).
Regarding claim 7, the combined teachings teach of the premixing device for the water heater according to claim 6, and the combined teachings further teach:
wherein:
a first support rib is disposed between the first support portion and the second support portion; and
a second support rib is disposed between the third support portion and the fourth support portion (See annotated Fig. 11 of Liu below).
Regarding claim 8, the combined teachings teach of the premixing device according to claim 5, and the combined teachings further teach:
wherein:
a third support portion is disposed in the housing, a second airflow passage being formed in the third support portion;
a fourth support portion is disposed in the second airflow passage, a second gas passage being formed in the fourth support portion; and
an end surface of the third support portion protrudes relative to the end surface of the first support portion (see rejection of claim 6 above and annotated Fig. 11 of Liu below, the housing as a third and fourth support portions, the fourth support portion is within the third support portion and the second airflow and gas passages are within the support portions)
Regarding claim 9, the combined teachings teach of the premixing device according to claim 8, and the combined teachings further teach:
wherein:
a first support rib is disposed between the first support portion and the second support portion; and
a second support rib is disposed between the third support portion and the fourth support portion (See rejection of claim 7 above and annotated Fig. 11 of Liu below, there is a first support rib disposed between the first and second support portions and a third support rib disposed between the third and fourth support portions)
Regarding claim 12, Liu teaches of:
A water heater, comprising a premixing device (¶ [0002], “This utility model relates to the field of water heater technology, and more specifically, to a Venturi device and a gas appliance”), the premixing device comprising:
a housing (Fig. 1, 100 has a housing 10), in which a first airflow passage (Fig. 9, 1121), a second airflow passage (Fig. 9, 1122), a first gas passage (Fig. 9, 1111), and a second gas passage are formed (Fig. 9, 1112); and
a turning plate rotatably disposed on the housing to adjust an opening degree of the first gas passage and an opening degree of the first airflow passage (Fig. 6, 20; ¶ [0059], “Thus, valve 20 can control the amount of gas and air entering the gas flow channel 11 by adjusting the normally closed gas flow channel 1111 and/or the normally closed air flow channel 1121”)
wherein the first gas passage is surrounded by the first airflow passage (1111 is surrounded by 1121)
Liu fails to explicitly teach:
an air guide hole directly opposite to the first airflow passage being formed on the turning plate
a deflector rib directly opposite to the first gas passage, wherein the deflector rib is disposed on the turning plate, and the deflector rib has an arc shape, and comprises an arc-shaped opening facing a pivot shaft of the turning plate
wherein a sectional area of the second gas passage is smaller than a sectional area of the first gas passage.
Schmidt teaches of:
an air guide hole directly opposite to the first airflow passage being formed on the turning plate (Fig. 4, 9 has air guide holes 13)
The primary reference can be modified to meet this/these limitation(s) as follows:
add an air guide hole to the turning plate 20 of Liu positioned in a way so that when 20 is closed air can still flow through the air guide hole from the first flow channel 1121
A person of ordinary skill in the art prior to the effective filing date of the claimed invention would have been motivated to make the above modification(s) because:
Since the change in flow rate of air to the amount of fuel pulled into the venturi due to a pressure difference is not 1:1, at low combustion levels where the turning plate is closed so that both the first air and gas channels are closed and the second air and gas channels are opened the air-gas ratio drops so that the mixture is rich in gas. Therefore, by adding the air guide holes to the turning plate some air can still flow through the turning plate via the air guide holes, maintaining an oxygen rich combustion gas mixture and resulting in reduced NOx formation (Schmidt, Fig. 5, the Y-axis represents air-gas ratio, a higher number means more air compared to gas, the X-axis represented the power output of the burner, line 15 represents a valve with no air guide holes, at low power levels there is a drop in the ratio resulting in an increase in pollutant formation, line 16 represents the valve of Fig. 4 with air guide holes, at low power levels the drop in the ratio is reduced and therefore pollutant formation is reduced)
Hishikawa teaches of:
A deflector rib (Fig. 18, 59) directly opposite to the first gas passage (59 is opposite s1), wherein the deflector rib is disposed on the turning plate (59 is disposed on 51)
The combined teachings can be modified to meet this/these limitation(s) as follows:
Add a deflector rib to 20 of Liu so that it extends into 1111
A person of ordinary skill in the art prior to the effective filing date of the claimed invention would have been motivated to make the above modification(s) because:
In a situation where the turning plate only opens a small amount, the gas passage would not be completely opened due to the insertion of the deflector rib, this would prevent a large increase in gas flow with a disproportionate increase in airflow
Hishikawa does not explicitly teach that the deflector rib is arc shaped and has an arc-shaped opening facing the pivot shaft, however at the time the invention was made it would have been obvious mater of design choice to a person of ordinary skill in the art to have made the deflector rib an arc shape comprising a middle part and two end portions, and a height of the deflector rib gradually decreases from the middle part toward the two ends instead of the angled rectangular shape shown, because applicant has not disclosed that the arc shape provides an advantage, is used for particular purpose or solves a stated problem. One of ordinary skill in the art would have expected the Applicant' s invention to perform equally well with an arc or rectangular shape, because both shapes performs the function of reducing the gas flow rate at low openings of the turning plate through the first gas passage equally well (MPEP 2144.04 IV B)
Kim teaches of:
wherein a sectional area of the second gas passage is smaller than a sectional area of the first gas passage (Figs. 3-4, 211 is smaller than 221)
The combined teachings can be modified to meet this/these limitation(s) as follows:
modify the sectional area of the outlet second gas passage to be smaller than the sectional area of the outlet of the first gas passage
A person of ordinary skill in the art prior to the effective filing date of the claimed invention would have been motivated to make the above modification(s) because:
modifying the sizes of the gas passages would turn the second gas and air passage into a low load portion of the dual venturi of Liu and the first gas and air passage into a high load portion of the dual venturi that can be adjusted through the control of the turning plate, this would improve the turn down ratio of the premixing device (Kim, ¶ [0007], “In particular, when the burner operates in low heating and hot-water load region, the combustion device may be frequently turned on/off, and thus the combustion state may be unstable. As a result, a variation in a temperature control increases to deteriorate durability of the device. Therefore, methods for improving the TDR of the burner that are applied to combustion devices have been proposed”; ¶ [0053], “On the other hand, in the relatively low-output load region, the premixing may be performed in only the first premixing chambers 310, but not be performed in the second premixing chamber 320 to improve the turndown ratio (TDR)”)
Regarding claim 14, the combined teachings teach of the water heater according to claim 12, and the combined teachings further teach:
wherein:
a first support portion is disposed in the housing, the first airflow passage being formed in the first support portion; and
a second support portion is disposed in the first airflow passage, the first gas passage being formed in the second support portion (See annotated Fig. 11 of Liu below, the first airflow passage 1121 has a first support portion and within the first airflow passage is the second support portion which has the first gas passage 1111 within it).
Regarding claim 15, the combined teachings teach of the water heater according to claim 14, and the combined teachings further teach:
wherein:
an end surface of a free end of the second support portion and an end surface of a free end of the first support portion are disposed obliquely (see annotated Fig. 6 of Liu below, the free end of the first and second support portions are disposed obliquely); and
the turning plate is rotatable to abut against the end surface of the second support portion and/or the end surface of the first support portion (see annotated Fig. 6 of Liu below, the turning plate 20 abuts the end supports of the first and second support portions).
Regarding claim 16, the combined teachings teach of the water heater according to claim 15, and the combined teachings further teach:
wherein the first support portion is inclined in an air flow direction from top to bottom (See both annotated Fig. 6 and 11 of Liu below, the first support portion is inclined from top to bottom in an airflow direction)
Regarding claim 17, the combined teachings teach of the water heater according to claim 15, and the combined teachings further teach:
wherein:
a third support portion is disposed in the housing, a second airflow passage being formed in the third support portion (see annotated Fig. 11 of Liu below, a second airflow passage 1122 is within the third support portion);
a fourth support portion is disposed in the second airflow passage, a second gas passage being formed in the fourth support portion (see annotated Fig. 11 of Liu below, the fourth support portion is within the second airflow passage 1122 and the second gas passage 1112 is within the fourth support portion); and
an end surface of the third support portion protrudes relative to the end surface of the first support portion (see annotated Fig. 11 of Liu below, the third support portion protrudes relative to the first support portion).
Regarding claim 18, the combined teachings teach of the water heater according to claim 17, and the combined teachings further teach:
wherein:
a first support rib is disposed between the first support portion and the second support portion; and
a second support rib is disposed between the third support portion and the fourth support portion (See annotated Fig. 11 of Liu below).
Regarding claim 19, the combined teachings teach of the water heater according to claim 16, and the combined teachings further teach:
wherein:
a third support portion is disposed in the housing, a second airflow passage being formed in the third support portion;
a fourth support portion is disposed in the second airflow passage, a second gas passage being formed in the fourth support portion; and
an end surface of the third support portion protrudes relative to the end surface of the first support portion (see rejection of claim 17 above and annotated Fig. 11 of Liu below, the housing as a third and fourth support portions, the fourth support portion is within the third support portion and the second airflow and gas passages are within the support portions)
Regarding claim 20, the combined teachings teach of the water heater according to claim 16, and the combined teachings further teach:
wherein:
a first support rib is disposed between the first support portion and the second support portion; and
a second support rib is disposed between the third support portion and the fourth support portion (See rejection of claim 18 above and annotated Fig. 11 of Liu below, there is a first support rib disposed between the first and second support portions and a third support rib disposed between the third and fourth support portions)
Regarding claim 21, the combined teachings teach of the water heater according to claim 1, and the combined teachings further teach:
wherein the deflector rib further comprises a middle part and two end portions, and a height of the deflector rib gradually decreases from the middle part toward the two ends (See rejection of claim 1 above and the design choice rationale to modify the deflector rib to match the shape of the claims)
Regarding claim 22, the combined teachings teach of the water heater according to claim 12, and the combined teachings further teach:
wherein the deflector rib further comprises a middle part and two end portions, and a height of the deflector rib gradually decreases from the middle part toward the two ends (See rejection of claim 12 above and the design choice rationale to modify the deflector rib to match the shape of the claims)
Annotated Figures
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742
1201
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Annotated Fig. 6 of Liu
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656
1100
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Annotated Fig. 11 of Liu
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MICHAEL J GIORDANO whose telephone number is (571)272-8940. The examiner can normally be reached M-Fr 8 AM - 5 PM EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Helena Kosanovic can be reached at (571) 272-9059. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MICHAEL JAMES GIORDANO/Examiner, Art Unit 3762
/HELENA KOSANOVIC/Supervisory Patent Examiner, Art Unit 3762
