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 .
Response to Arguments
Applicant’s arguments with respect to claim(s) 1 and 12 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.
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)
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,
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, 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 instead of the 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 restricting airflow 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 2, the combined teachings teach of the premixing device for the water heater according to claim 1, and the combined teachings further teach:
wherein the first gas passage is surrounded by the first airflow passage (Liu, Fig. 12, 1121 surrounds 1111)
Regarding claim 3, the combined teachings teach of the premixing device for the water heater according to claim 2, 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”)
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,
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, 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 instead of the 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 restricting airflow 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 13, the combined teachings teach of the water heater according to claim 12, and the combined teachings further teach:
wherein the first gas passage is surrounded by the first airflow passage (Liu, Fig. 12, 1121 surrounds 1111)
Regarding claim 14, the combined teachings teach of the water heater according to claim 13, 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)
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
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 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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/MICHAEL JAMES GIORDANO/Examiner, Art Unit 3762
/VIVEK K SHIRSAT/Primary Examiner, Art Unit 3762
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