DETAILED ACTION
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.
Claim(s) 1-5, 7 are rejected under 35 U.S.C. 103 as being unpatentable over Mihe (UA 113544 C2) in view of Batz (EP 2986911 B1).
Regarding claim 1, Mihe discloses a burner comprising:
a first nozzle (Fig. 2; 8) having a tubular shape about a burner axis and including a main fuel outlet (32) that discharges a fuel-air mixture (21) containing main fuel and primary combustion air and a flame holding plate (Fig. 5; 17a) located around the main fuel outlet;
a second nozzle (Fig. 2; 15) located coaxially with the first nozzle and including a secondary air outlet that emits secondary combustion air at an outer peripheral side of the main fuel outlet; and
auxiliary fuel injection nozzles, wherein:
the auxiliary fuel injection nozzles include auxiliary fuel outlets lined up along an outer peripheral edge of the flame holding plate or
auxiliary fuel outlets (Fig. 5; 17aa) located inside the outer peripheral edge of the flame holding plate and outside an inner peripheral edge of the flame holding plate (17a): and
the auxiliary fuel outlets discharge gas fuel as auxiliary fuel toward a boundary between flow of the fuel-air mixture discharged from the main fuel outlet and flow of the secondary combustion air discharged from the secondary air outlet.
Mihe fails to disclose: where the auxiliary fuel injection nozzles extend along an outer surface of the first nozzle in parallel with the burner axis.
Batz teaches a burner comprising fuel injection nozzles (Fig. 2; 21 or 111) extending along an outer surface of the first nozzle (10) in parallel with the burner axis.
It would have been obvious to a person skilled in the art at the time of effective filing of the application to modify Mihe where the auxiliary fuel injection nozzles extend along an outer surface of the first nozzle in parallel with the burner axis. The motivation to combine is so that the auxiliary fuel can be supplied and distributed uniformly to the auxiliary fuel outlets for uniform flame and combustion conditions.
Regarding claim 2, modified Mihe discloses the burner according to claim 1, wherein the auxiliary fuel injection nozzles are joined to an outer surface of the first nozzle (both Mihe and Batz disclose where the nozzles are joined to a holding plate of the first nozzle at the outlet end).
Regarding claim 3, modified Mihe discloses the burner according to claim 1, wherein downstream ends of the auxiliary fuel injection nozzles extend through the flame holding plate (see Fig. 6 of Mihe and Fig. 1 of Batz).
Regarding claim 4, modified Mihe discloses the burner according to claim 1, wherein: the flame holding plate includes cutouts at an outer peripheral edge thereof (Fig. 6 of Mihe shows these cutouts); and downstream ends of the auxiliary fuel injection nozzles extend through the cutouts (Fig. 1 of Batz teaches where the tip 22 of the nozzle 21 extends through the holding plate).
Regarding claim 5, modified Mihe discloses the burner according to claim 1, wherein the auxiliary fuel outlets discharge the gas fuel to forward flow of a circulating vortex generated at the boundary between the flow of the fuel-air mixture and the flow of the secondary combustion air, the forward flow flowing toward a downstream side. This limitation is an intended effect from operating the burner of claim 1. Since modified Mihe discloses all of the elements of claim 1, then modified Mihe would also produce the circulating vortex.
Regarding claim 7, modified Mihe discloses the burner according to claim 1 wherein the auxiliary fuel outlets are switchable so as to emit combustion air instead of the gas fuel. The outlets can emit any type of gas.
Claim(s) 8 is rejected under 35 U.S.C. 103 as being unpatentable over Mihe (UA 113544 C2) in view of Batz (EP 2986911 B1), as applied to claim 1, and further in view of Zhang (US 20210140634 A1).
Regarding claim 8, modified Mihe discloses the burner according to claim 1, except wherein the gas fuel is an ammonia gas. However, Zhang teaches a burner wherein the gas fuel is an ammonia gas (abstract).
It would have been obvious to a person skilled in the art at the time of effective filing of the application to modify Mihe wherein the gas fuel is an ammonia gas. The motivation to combine is to provide a fuel that does not produce CO2 (see para. 3 of Zhang).
Claim(s) 9 is rejected under 35 U.S.C. 103 as being unpatentable over Mihe (UA 113544 C2) in view of Batz (EP 2986911 B1), as applied to claim 1, and further in view of Murakami (US 20170356648 A1).
Regarding 9, modified Mihe fails to disclose a combustion furnace comprising: a high-temperature reduction zone which has a reduction atmosphere and at which at least one burner according to claim 1 is located; and a low-temperature oxidation zone which has an oxidizing atmosphere and is lower in temperature than the high-temperature reduction zone and into which a combustion gas generated in the high-temperature reduction zone flows.
However, Murakami teaches a combustion furnace comprising:
a high-temperature reduction zone (102) which has a reduction atmosphere and at which at least one burner is located (para. 70); and
a low-temperature oxidation zone (103) which has an oxidizing atmosphere and is lower in temperature than the high-temperature reduction zone and into which a combustion gas generated in the high-temperature reduction zone flows (para. 70).
It would have been obvious to a person skilled in the art at the time of effective filing of the application to modify Mihe to include a combustion furnace comprising: a high-temperature reduction zone which has a reduction atmosphere and at which at least one burner according to claim 1 is located; and a low-temperature oxidation zone which has an oxidizing atmosphere and is lower in temperature than the high-temperature reduction zone and into which a combustion gas generated in the high-temperature reduction zone flows.
Mihe discloses that the burner can be used in a boiler and Kawasaki discloses an example boiler where the burner can be used.
Allowable Subject Matter
Claim 6 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Conclusion
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/JASON LAU/Primary Examiner, Art Unit 3762
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