Prosecution Insights
Last updated: April 19, 2026
Application No. 17/921,249

MELTING/REFINING FURNACE FOR COLD IRON SOURCES, AND MELTING/REFINING FURNACE OPERATION METHOD

Non-Final OA §103
Filed
Oct 25, 2022
Examiner
MCGUTHRY BANKS, TIMA MICHELE
Art Unit
1733
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Taiyo Nippon Sanso Corporation
OA Round
3 (Non-Final)
82%
Grant Probability
Favorable
3-4
OA Rounds
2y 6m
To Grant
83%
With Interview

Examiner Intelligence

Grants 82% — above average
82%
Career Allow Rate
941 granted / 1154 resolved
+16.5% vs TC avg
Minimal +2% lift
Without
With
+1.9%
Interview Lift
resolved cases with interview
Typical timeline
2y 6m
Avg Prosecution
65 currently pending
Career history
1219
Total Applications
across all art units

Statute-Specific Performance

§101
0.8%
-39.2% vs TC avg
§103
40.3%
+0.3% vs TC avg
§102
19.4%
-20.6% vs TC avg
§112
33.0%
-7.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1154 resolved cases

Office Action

§103
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 01/19/2026 has been entered. Status of Claims Claims 1 and 2 are currently amended, Claim 3 is as originally filed, Claims 4-7, 10, and 11 are as previously presented, Claims 8 and 9 are withdrawn, and Claim 12 is new. Claim Rejections - 35 USC § 103 The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action. Claim Rejections - 35 USC § 103 Claims 1-4, 6, 7, and 10-12 are rejected under 35 U.S.C. 103 as being unpatentable over Hagihara et al (US 11,053,559 B2), which is in the same patent family as JP 2017-179574 A, in view of Suwa et al (US 5,149,261). Hagihara et al teaches a melting and refining furnace and as represented in the annotated drawings: PNG media_image1.png 478 637 media_image1.png Greyscale PNG media_image2.png 382 814 media_image2.png Greyscale The supply hole 4A reads on the claimed “through-hole.” The reference numbers for FIGs. 2 and 4 are defined in column 4. However, Hagihara et al does not teach a high-temperature gas generator as claimed. Suwa et al teaches an oxygen heater as represented below in the drawing: PNG media_image3.png 402 652 media_image3.png Greyscale The reference numbers for FIG. 3 are defined in columns 11-13. Oxygen at 106 reads on “a first gas flow path pipe for supplying the combustion-supporting gas to the burner.” Auxiliary combustion oxygen nozzles 107 read on “a second gas flow path pipe for supplying the gas to be heated to the pre-heating chamber.” Suwa et al teaches the following: In place of the oxygen-supplying passage 105, there may be employed two passages for supplying oxygen respectively to the outlet and nozzle holes 106 and 107. Alternatively, oxygen may be supplied by two passages branched before the oxygen was introduced into outer cylinder 101 of the lance. However, these arrangements are not preferred since it causes complications in the construction of the lance (column 12, line 64 to column 13, line 4). A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments. Nonpreferred and alternative embodiments constitute prior art. Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. See MPEP § 2123. Therefore, Suwa et al teaches an embodiment where the first and second gas flow path pipes for 106 and 107 are separated from one another and supplied by a single source (“two passages branched”). Suwa et al teaches the first gas flow path and the second gas flow path are connected to a combustion-supporting gas supply source. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use the oxygen heater of Suwa et al to supply oxygen to the burner lance of Hagihara et al, since Suwa et al teaches providing an oxygen heater capable of heating a large quantity of oxygen efficiently without severely lowering the purity of oxygen (column 3, lines 40-44), which is required in the refining of ferrous and nonferrous metals (column 1, lines 10-12). Regarding Claim 2, Suwa et al teaches a combustion chamber 4 (FIG. 1), a fuel flow path a, a combustion-supporting gas flow path 106, and a gas to be heated flow path 107 (FIG. 3). Path 107 bypasses the combustion chamber. Regarding Claim 3, Suwa et al teaches the internal wall 2 (FIG. 1) may be provided with a cooling jacket (column 4, lines 25-28). Regarding Claim 4, Hagihara et al teaches a thermometer which is configured to measure a temperature in the furnace. Hagihara et al also teaches a control device which is configured to receive a measured value of a furnace temperature from the thermometer and a measured value of a component concentration and a flow rate from the exhaust gas analyzer, analyze the measured values, and transmit a control signal for controlling a supply amount of the combustion-supporting fluid, the fuel fluid, and the carbon source which are supplied into the furnace (column 2, lines 20-52), which reads on the burner-lance. Suwa et al teaches a control means for controlling the flow rate of oxygen supplied to the combustion chamber (column 4, lines 10-15); the fuel supply means supplies fuel at a predetermined flow rate (lines 38 and 39). Regarding Claim 6, Suwa et al teaches the combustion-supporting gas is oxygen (FIG. 3). Regarding Claim 7, Suwa et al teaches the gas to be heated is oxygen (FIG. 3). Regarding Claim 10, Suwa et al teaches the temperature of the mixed hot gas is 700-1000 °C (column 6, lines 61-63), which overlaps the claimed range. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists because the prior art discloses the utility of the composition over the entire disclosed range. See MPEP § 2144.05. Regarding Claim 11, Suwa et al teaches the pre-heating chamber is upstream from the oxygen burner lance, and Hagihara et al teaches the lance is upstream of the furnace interior. Regarding Claim 12, Suwa et al teaches oxygen may be supplied by two passages branched before the oxygen was introduced into outer cylinder 101 of the lance, which reads on a combustion-supporting gas supply source configured to supply both gases. Claims 1-7 and 10-12 are rejected under 35 U.S.C. 103 as being unpatentable over Haissig (US 5,943,360) in view of Suwa et al. Haissig teaches an electric arc furnace with a post combustion chamber of the exhaust gas (abstract) as represented below in the annotated drawings. The injectors 104 are burners (column 10, lines 28-35). PNG media_image4.png 496 526 media_image4.png Greyscale PNG media_image5.png 496 764 media_image5.png Greyscale The through-holes are taught by the burner protruding in the furnace. The burner can be positioned at the end of the oxygen lance (column 6, lines 40 and 41). The oxygen burner lance is connected to the amount of the fuel fluid and combustion-supporting fluid (column 5, lines 3-11). The burner at the end of the oxygen lance provides a preheating flame (column 6, lines 45-49). However, Haissig does not teach a high temperature gas generator as claimed. Suwa et al teaches an oxygen heater as represented above in FIG. 3. The reference numbers for FIG. 3 are defined in columns 11-13. Oxygen at 106 reads on “a first gas flow path pipe for supplying the combustion-supporting gas to the burner.” Auxiliary combustion oxygen nozzles 107 reads on “a second gas flow path pipe for supplying the gas to be heated to the pre-heating chamber.” Suwa et al teaches the following: In place of the oxygen-supplying passage 105, there may be employed two passages for supplying oxygen respectively to the outlet and nozzle holes 106 and 107. Alternatively, oxygen may be supplied by two passages branched before the oxygen was introduced into outer cylinder 101 of the lance. However, these arrangements are not preferred since it causes complications in the construction of the lance (column 12, line 64 to column 13, line 4). A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments. Nonpreferred and alternative embodiments constitute prior art. Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. See MPEP § 2123. Therefore, Suwa et al teaches an embodiment where the first and second gas flow path pipes for 106 and 107 are separated from one another and supplied by a single source (“two passages branched”). Suwa et al teaches the first gas flow path and the second gas flow path are connected to a combustion-supporting gas supply source. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use the oxygen heater of Suwa et al to supply oxygen to the burner lance of Hagihara et al, since Suwa et al teaches providing an oxygen heater capable of heating a large quantity of oxygen efficiently without severely lowering the purity of oxygen (column 3, lines 40-44), which is required in the refining of ferrous and nonferrous metals (column 1, lines 10-12). Regarding Claim 2, Suwa et al teaches a combustion chamber 4 (FIG. 1), a fuel flow path a, a combustion-supporting gas flow path 106, and a gas to be heated flow path 107. Path 107 bypasses the combustion chamber. Regarding Claim 3, Suwa et al teaches the internal wall 2 (FIG. 1) may be provided with a cooling jacket (column 4, lines 25-28). Regarding Claim 4, Haissig teaches a radiation thermometer (column 4, line 50). The thermometer is installed on the oxygen burner lance (column 5, lines 3-11). Regarding Claim 5, Haissig teaches the discharge passage is represented by at least 13 in FIG. 8. The gas analyzer 160 analyzes CO and other gases (column 9, lines 45-47). The temperature of the exhaust gas is measured before entering the post combustion chamber (column 2, lines 33-42). Based on the exhaust gas volume, it is possible to define the weight percentage of the exhaust gases (column 9, lines 37-41). The venturi 152 is used to calculate the volume of the gas (10, lines 48-50). The post combustion system includes a temperature monitor that measures the initial and final temperatures of the exhaust gas and includes a gas analyzer. The amount of gas and temperature is fed to a controller (column 9, line 45 to column 10, line 4). Based on the values of the temperature, oxygen flow in the lance, burner power, amount of air entering the furnace, and the values determined in the gas analysis before and after combustion, the water-cooled injectors are set and varied as necessary (column 10, lines 55-65). Regarding Claim 6, Suwa et al teaches the combustion-supporting gas is oxygen (FIG. 3). Regarding Claim 7, Suwa et al teaches the gas to be heated is oxygen (FIG. 3). Regarding Claim 10, Suwa et al teaches the temperature of the mixed hot gas is 700-1000 °C (column 6, lines 61-63), which overlaps the claimed range. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists because the prior art discloses the utility of the composition over the entire disclosed range. See MPEP § 2144.05. Regarding Claim 11, Suwa et al teaches the pre-heating chamber is upstream from the oxygen burner lance, and Haissig teaches the lance is upstream of the furnace interior. Regarding Claim 12, Suwa et al teaches oxygen may be supplied by two passages branched before the oxygen was introduced into outer cylinder 101 of the lance, which reads on a combustion-supporting gas supply source configured to supply both gases. Response to Arguments Applicant's arguments filed 01/19/2026 have been fully considered but they are not persuasive. Applicant argues that Suwa et al does not teach the combination of first and second gas flow pipes and first and second gas flow paths that are linked to a combustion-supporting gas supply source. These limitations are addressed above in the rejections under 35 U.S.C. 103. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to Tima M. McGuthry-Banks whose telephone number is (571)272-2744. The examiner can normally be reached Monday through Friday, 7:30 am to 4:00 pm. 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, Keith D. Hendricks can be reached at (571) 272-1401. 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. Tima M. McGuthry-Banks Primary Examiner Art Unit 1733 /TIMA M. MCGUTHRY-BANKS/Primary Examiner, Art Unit 1733
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Prosecution Timeline

Oct 25, 2022
Application Filed
Jul 11, 2025
Non-Final Rejection — §103
Sep 22, 2025
Response Filed
Oct 28, 2025
Final Rejection — §103
Jan 19, 2026
Request for Continued Examination
Jan 27, 2026
Response after Non-Final Action
Feb 10, 2026
Non-Final Rejection — §103 (current)

Precedent Cases

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

3-4
Expected OA Rounds
82%
Grant Probability
83%
With Interview (+1.9%)
2y 6m
Median Time to Grant
High
PTA Risk
Based on 1154 resolved cases by this examiner. Grant probability derived from career allow rate.

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