DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application is being examined under the pre-AIA first to invent provisions.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 02/09/2026 has been entered.
Status of Claims
Claims 14-19, 21-23, 25 and 26 remain under consideration in the application and none of the claims is amended.
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.
Claims 14-19, 21 and 22 rejected under 35 U.S.C. 103 as being unpatentable
over Slagley (US Patent No. 4,572,487) in view of Kinney (US Patent No. 2,398,098).
Regarding claim 14, Slagley teaches a device (i.e., tuyere (12), see abstract, column 1, lines 5-20, column 3, lines 44-56 and figures 1&2) configured to inject a hot gas into a shaft furnace (see column 3, lines 44-45), the device comprising: an external casing (i.e., main tubular tuyere portion (15), see figure 2 and column 3, lines 58-68) having a rear (i.e., upstream end (16) see figure 2 and column 3, lines 58-68) and a front face (i.e. downstream nose portion (17) , see figure 2 and column 3, lines 58-68), the front face being provided with an outlet for gas injection into the shaft furnace (see in figure 2, the nose portion (17) defines an opening for gas discharge into the furnace reaction space); and an internal casing (i.e., the replaceable liner (20) comprising a metallic liner (22) and a refractory layer (23), see figures 2 and 4 and column 3, lines 58-68) located inside the external casing (15) and made of a steel (i.e., the liner (22) is made of stainless steel, see column 5, lines 27-29) able to resist to a temperature up to 1200°C (see column 4, lines 18-32 and column 5, lines 18-30).
It is noted that though the tuyere assembly of Slagley is used for injecting a hot gas or a hot air blast into the blast furnace and not necessarily for injecting a reducing gas as recited in the preamble of the claim 14, however, the tuyere of Slagley is capable of injecting a reducing gas for the following reasons: (1) that a reducing gas is in the same state of matter as hot gas and (2) that said tuyere includes substantially all and/or the same structure features as in claim 14. In addition, the reducing gas recited in the instant claim 14 only constitutes an intended use of the claimed injection device. In addition, with reference to MPEP 2114.II., the Court held that "[A]pparatus claims cover what a device is, not what a device does, and that A claim containing a "recitation
with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim.
Slagley in figures 2 and 4, shows an injection device in which the front face of the external casing (i.e., main tubular tuyere portion (15), see figure 2 and column 3, lines 58-68) appears to be circular in shape, but fails to teach said front face being triangular in shape as claimed.
Kinney teaches an injection device or a tuyere for use with a blast furnace (see Kinney, page 1, column 1, lines 1-15); said tuyere defining an inner casing or shell (6, see Kinney, figure 5 and page 1, column 1, line 53-column 2, line 27) and an external casing or shell (4 see Kinney, figure 5 and page 1, column 1, line 53-column 2, line 27); wherein the shape of the front face of the external casing (4) is non-circular in cross section including: an ovate shape, semi-ovular shape, or semi-elliptical shape or a raindrop or conoidal shape with a triangular bottom portion (see Kinney, figure 5 and page 1, column 2, line 18-page 2, column 1, line 22); wherein said shapes are selected for the purpose of aiding molten material flowing down the interior of the furnace over the tuyere will slough off thereby preventing the accumulation of material on said front face of the tuyere and consequently prolonging the service life of the tuyere (see Kinney, page 2, column 1, lines 1-10).
It would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the injection device of Slagley, to use an injection device with an external casing with a non-circular shaped front face to include an ovate shape, semi-ovular shape, or semi-elliptical shape or a raindrop or conoidal shape with a
triangular bottom portion as exemplified by Kinney and that would provide the function and advantage of aiding molten material flowing down the interior of the furnace over the tuyere to slough thereby preventing the accumulation of material on said front face of the tuyere and consequently prolonging the service life of the tuyere (see Kinney, page 2, column 1, lines 1-10).
It should be noted that, though in Kinney, the con-circular front face of the external case as show in figure 5 is not exactly triangular in shape as the instant claim requires, however the injection device of Kinney provides substantially the same function and advantage by preventing accumulation of material on the front face of the injection device as in the instant claimed injection device design. Furthermore, with reference to MPEP 2144.04. IV.B which pertains to the obviousness of changes in shape, similar to the instantly-claimed shape of the front face of the external casing and that taught by Kinney, the court held that he configuration of the claimed disposable plastic nursing container “was a matter of choice which a person of ordinary skill in the art would have found obvious absent persuasive evidence that the particular configuration of the claimed container was significant.” Slagley in view of Kinney, therefore reads on the claim.
Regarding claim 15, Slagley in view of Kinney teaches an injection device in which the refractory layer 23, see Slagley, figures 2 and 4) is located between the external casing (15) and the internal casing (steel liner 22 of the inner casing, see Slagley, column 3, lines 62-68).
Regarding claim 16, Slagley in view of Kinney teaches an injection device in
which the internal steel casing (22) is made of stainless steel (see Slagley, column 5,
lines 27-29).
Regarding claim 17, Slagley in view of Kinney teaches an injection device or tuyere (12, see Slagley, figure 2) which comprises at least an inner casing (22) that is uncooled or in other words has no attached cooling jacket provided (see column 5, lines 14-17); and therefore; Slagley in view of Kinney substantially reads on the claim.
Regarding claim 18, Slagley in view of Kinney teaches an injection device in which the shaft furnace is a blast furnace (see Slagley, abstract and column 3, lines 44-45).
Regarding claim 19, Slagley in view of Kinney teaches an injection device that is fastened or bolted to the shaft furnace or blast furnace wall (10, see Slagley, figure 1 and column 4, lines 55 -68).
Regarding claims 21 and 22, Slagley in figures 1 and 2, shows a tuyere (12) designed with a downward inclination, and with the internal casing (22&23) also aligned in the same inclination therewith, hence injection of the hot gas into the blast furnace reaction space would necessarily be downward in the same manner as claimed; furthermore, because the internal casing as shown in figure 2 for example is inclined slightly with respect to the horizontal axis at a none zero angle to blast furnace wall, the claimed angle of inclination α between 0 and 30° is met. Thus, Slagley figures 1 and 2
read on both claims 21 and 22. Slagley in view of Kinney, therefore meets substantially all aspects of the claim.
Claim 23 is rejected under 35 U.S.C. 103 as being unpatentable over
Slagley (US Patent No. 4,572,487) in view of Kinney (US Patent No. 2,398,098) of as
applied to claim 14 above, and further in view of Miller (US Patent No.1,298,761).
Slagley in view of Kinney fails to teach a stone box on the upper part of the front face.
Miller teaches a device (i.e., supplementary tuyere 150, see Miller, figures 1 &3, page 2, lines 86-104 and page 3, lines 1-14) for injecting at least a hot gas into a shaft furnace, the device having a nozzle portion (34, see Miller, figures 1 and 3) defining an upper part and a lower part (see figures 1 and 3), and a fire brick mass (38, see Miller, figure 3) provide at said upper part to reinforce and strengthen said upper part to increase the service life of the front face or hot face of the nozzle portion (34, see Miller, page 3, lines 1-14).
It would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the injection device or tuyere of Slagley in view of Kinney to provide a fire brick mass at said upper part of the front face or hot face of the nozzle portion as exemplified by Miller so as to provide the advantage and/or benefit of reinforcing and/or strengthening said upper part to increase the service life of the front face or hot face of the nozzle portion.
Claims 25 and 26, are rejected under 35 U.S.C. 103 as being unpatentable over
Slagley (US Patent No. 4,572,487) in view of Kinney (US Patent No. 2,398,098) of as applied to claim 14 above, and further in view of Stoecker (US Patent No. 1,994,115).
Regarding claims 25 and 26, Slagley in view of Kinney fails to teach an injection device in which the front face of the external casing is composed of an upper part and of a lower part, the lower part being recessed from the upper part and the gas injection outlet being provided in the lower part of the front face or the lower part being inwardly chamfered from the upper part and the gas injection outlet being provided in the lower part of the front face.
Stoecker teaches an injection device in the form of a tuyere configured for gas injection into a shaft furnace (see Stoecker, figures 1 and 3 and the entire disclosure); wherein the tuyere includes an external casing having a front face composed of an upper part (i.e. wedge like insertion 2, see Stoecker , figures 1 and 3 and page 1, column 2, lines 5-20) and of a lower part (i.e., lower inner nozzle plate 3, see Stoecker , figures 1 and 3 and page 1, column 2, lines 5-20) the lower part being recessed from the upper part and the gas injection outlet being provided in the lower part of the front face (see figure 3 shows as such) or the lower part being inwardly chamfered (see in figure 3, the lower part or plate 3 is chamfered) from the upper part; and with and the gas injection outlet being provided in the lower part of the front face.
It would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the injection device or tuyere of Slagley in view of Kinney to include lower part being recessed from the upper part and lower part being inwardly chamfered from the upper part as taught by Stoecker to provide the benefit of preventing burden material from obstructing the tuyere gas injection outlet (see
Stoecker, entire disclosure).
Response to Arguments
Applicant’s arguments, filed 06/10/2026, with respect to the rejection(s) of
claims 14-19, 21-23, 25 and 26 under 103 have been fully considered and are
persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made by Slagley (US Patent No. 4,572,487) in view of Kinney (US Patent No. 2,398,098).
Applicant’s principal argument is that Slagley, fails to teach an injection device in which an external casing having a rear and a front face, the front face being provided with an outlet for gas injection into the shaft furnace, wherein the front face of the external casing has a triangular shape.
In response, it is noted that while the Examiner agrees Slagley, fails a front face of the external casing having a triangular shape, Kinney (a newly introduced prior art) teaches an injection device that comprises an external casing with a non-circular shaped front face to include an ovate shape, semi-ovular shape, or semi-elliptical shape or a raindrop or conoidal shape with a triangular bottom portion as exemplified by Kinney and that would provide the function and advantage of aiding molten material flowing down the interior of the furnace over the tuyere will slough off the more steeply sloped bottom portion of the inverted raindrop or conoidal form, doing away with accumulation on the underside of the tuyere and thereby prolonging the service life of the tuyere. Therefore, Kinney remedies the stated deficiencies of Slagley.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Zanetta et al. (US 4,771,993) and Suzuki et al. (US 4,490,171) are also cited in PTO-892.
Any inquiry concerning this communication or earlier communications from the
examiner should be directed to MICHAEL ABOAGYE whose telephone number is (571)272-8165. The examiner can normally be reached 8:30AM-5:00PM.
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/M.A/Examiner, Art Unit 1733
/JESSEE R ROE/Primary Examiner, Art Unit 1759
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