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 .
Previous citation to U.S. Patent No. 11,454,477 in the Double Patenting rejections presented 10/25/2024 and 03/05/2025 was in error. Any inconvenience to applicant is sincerely regretted.
NOTE: Applicant is cautioned against the introduction of new matter to the application, whether in the Specification or Claims. Applicant is requested to demonstrate corresponding support and explanation for any amendment.
Continued Examination Under 37 CFR 1.114
Receipt is acknowledged of a request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e) and a submission, filed on 07/07/2025.
Claim Objections
Claim 16 is objected to because of the following informalities: Claim 16 uses semicolons where it appears commas are more appropriate. Applicant is encouraged to set forth clearly that each element is part of a proper Markush Group.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 6 and 11-12 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 6 recites “further comprising the furnace” when previous mention is to a curved furnace within the scope of an intended use of the claimed apparatus, an electromagnetic stirrer. Claim 1 on which Claim 6 depends does not positively require a furnace. In other words, the apparatus of Claim 1 is directed to a stirrer and does not positively include any furnace. Therefore, “the furnace” in Claim 6 lacks proper antecedent basis.
Note that when a new component is introduced into a claim, the claim “further comprising” should refer to “a component” not “the component.”
Claims 11-12 set out to claim a distance between the end face of the stirrer teeth and the outer wall of a furnace. However, a furnace is not positively recited as being present in Claim 1 upon which Claims 11 and 12 ultimately depend. For this reason, there can be no distance between the teeth of the electromagnetic stirrer apparatus and a component that has not been positively required by Claim 1.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-4, 13-14, 16, and 18 are rejected under 35 U.S.C. 102(a)(1) and (a)(2) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Hanff US 2875261 A.
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Hanff US 2875261 A Fig. 1
Regarding Claim 1, Hanff ‘261 teaches an electromagnetic stirrer including three or more pole members (meeting the limitation for teeth) configured to generate a magnetic field (Column 1/Lines 32-45, Fig. 1). The three or more pole members (teeth) have an end defining a tooth end face, and each tooth end face has a center point (Fig. 1).
As can be seen in Fig. 1 of Hanff ‘261, the end face for at least one of the pole members (meeting the limitation for teeth) is angled relative to the end face for at least one of the other pole members (meeting the limitation for teeth). Note that ‘zero degrees’ is an angle, and no convexity or concavity has been indicated in Claim 1. Additionally, each pole member/tooth end face is configured to be positioned adjacent to a curved furnace such that an air gap is defined between each tooth end face and the furnace. Though Fig. 1 of Hanff ‘261 is a schematic, it exemplifies a technology known to persons of ordinary skill in the art at the time of filing the invention publicly available in 1957. Persons of ordinary skill in the art at the time of filing the invention would understand each pole member (meeting the limitation for teeth) to have a center point, with Fig. 1 being but an example.
Regarding the limitation that a distance of the air gap is equal for each tooth end face at the center point, a measure of relative proximity requires two points. Applicant’s claim is to an electromagnetic stirrer apparatus, not to a curved furnace. The claims do not positively recite the inclusion of a furnace as part of the claimed stirrer apparatus. Though an ‘air gap’ is a term of art, two points are needed to define a distance, whereas only one point has been positively recited and established in the claims (i.e. the tooth end face center point). The limitation that each end tooth is capable of being positioned with a uniform air gap is recited as intended use. As such, the electromagnetic stirrer of Hanff ‘261 meets the limitation of the instant claim.
Alternatively and additionally, it would have been obvious to one having ordinary skill in the art at the time of filing the invention to configure each tooth end face of the teeth in Hanff ‘261 to be positioned adjacent to a curved furnace such that an air gap is defined between each tooth end face and the furnace, a distance of the air gap being equal for each tooth end face at the centre-point. One of ordinary skill in the art at the time of filing the invention would have been motivated by a desire to maximize the efficiency of the charge of the electromagnetic stirrer and provide consistency of the electromagnetic path to a furnace, thus being motivated to craft the teeth of the electromagnetic stirrer to have an equal distance at the centre-point of each tooth end face to a curved furnace based on the teachings of Hanff ‘261 e.g. at (Column 1 Lines 40-45). One of ordinary skill in the art at the time of filing the invention would have been motivated by a desire to improve homogeneity of electromagnetic stirring, and efficiency of electromagnetic stirring of molten material within a furnace to place each tooth of an electromagnetic stirrer at an equal distance to the surface of a curved furnace.
Generally, changes in shape will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such shape is critical. See MPEP 2141.01(a) I. Further, “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Regarding Claims 2 and 13-14, Hanff ‘261 teaches the limitations set forth above. The center point for each tooth end face in Hanff ‘261 lies along a first arc that is concentric with a second arc defined by a perimeter of a furnace (Fig. 1).
It would have been obvious to a person of ordinary skill in the art at the time of filing the invention to shape the tooth end face with a curvature such that an entirety of the tooth end face of at least one of the three or more teeth would lie along the first arc, creating a concavity. One of ordinary skill in the art at the time of filing the invention would have been motivated by a desire to maximize the efficiency of the charge of the electromagnetic stirrer and provide consistency of the electromagnetic path to a furnace, to craft the teeth of the electromagnetic stirrer to closely match and align with the curvature of a curved furnace. Further, one of ordinary skill in the art at the time of filing the invention would have been motivated by a desire to improve homogeneity of the molten metal acted upon by the electromagnetic stirring, and the efficiency of electromagnetic stirring of molten material within a furnace to craft the teeth of the electromagnetic stirrer to match the curvature of a curved furnace based on the teachings of Hanff ‘261 e.g. at (Fig. 1, Column 1/Lines 40-45).
Regarding Claim 3, Hanff ‘261 teaches the limitations set forth above. The pole members/teeth of Hanff ‘261 are a conventional coil-wound magnetic material (Column 2/Lines 14-17), meeting the limitation of the instant Claim for teeth having a tooth edge around the tooth end faces.
Regarding Claim 4, Hanff ‘261 teaches the limitations set forth above. Hanff ‘261 teaches at (Fig. 1) the tooth end face plane for at least one of the teeth is not in the same plane with the tooth end face plane for at least one of the other teeth, meeting the limitation of the instant Claim.
Regarding Claim 16, Hanff ‘261 teaches the limitations set forth above. Hanff ‘261 further teaches at (Column 5/Lines 38-54) its apparatus comprises a control system for generating current, meeting the limitation of the instant Claim.
Regarding Claim 18, Hanff ‘261 teaches the limitations set forth above. Hanff ‘261 further teaches an electromagnetic stirrer for stirring molten metal including three or more teeth configured to generate a magnetic field in a method of stirring (Column 1/Lines 35-44, Fig. 1). A current is applied to a first and second electrically conducting coil of the electromagnetic stirrer (Column 2/Lines 64-71). The three or more teeth have an end defining a tooth end face, are positioned relative to a curved furnace (meeting the limitation for a curved container) such that an air gap is defined between the tooth end faces and outer wall of the curved furnace (meeting the limitation for the curved container) (Fig. 1). Regarding the limitations of a first and second time, application of a pulsed current (Column 1/Lines 35-40) meets the limitation for a first and second magnetic field configuration.
Regarding the limitation that a distance of the air gap is equal for each tooth end face at the center point, Hanff ‘261 e.g. at (Fig. 1, Column 1/Lines 40-45) teaches a long-standing practice of angling electromagnetic stirrer teeth to match the curvature of a curved furnace. Hanff ‘261 expressly teaches modifying angled electromagnetic stirrer teeth such that electromagnetic stirring is regulated (Column 5/Lines 26-37). Further, Hanff ‘261 provides motivation to form a “closely adjacent” spacing between the electromagnetic stirrer and surface of a curved furnace (Column 2/Lines 4-8). See MPEP 2144.05 II. As such, the electromagnetic stirrer of Hanff ‘261 meets the limitation of the instant claim.
Alternatively and additionally, it would have been obvious to one having ordinary skill in the art at the time of filing the invention to configure each tooth end face of the teeth in Hanff ‘261 to be positioned adjacent to a curved furnace such that an air gap is defined between each tooth end face and the furnace, a distance of the air gap being equal for each tooth end face at the centre-point.
One of ordinary skill in the art at the time of filing the invention would have been motivated by a desire to improve the charge of the electromagnetic stirrer and improve the electromagnetic path to a furnace to craft the teeth of the electromagnetic stirrer to have an equal distance at the centre-point of each tooth end face to a curved furnace based on the teachings of Hanff ‘261 e.g. at (Column 1 Lines 40-45). One of ordinary skill in the art at the time of filing the invention would have been motivated by a desire to improve homogeneity of electromagnetic stirring, and efficiency of electromagnetic stirring of molten material within a furnace to place each tooth of an electromagnetic stirrer at an equal distance to the surface of a curved furnace.
Generally, changes in shape will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such shape is critical. See MPEP 2141.01(a) I. Further, “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Claims 6-9 are rejected under 35 U.S.C. 103 as being unpatentable over Hanff US 2875261 A as applied to Claims 1-4, 13-14, 16, and 18 above, further in view of Folgero et al. US 3200185 A.
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Folgero et al. US 3200185 A, Figs. 1-2
Regarding Claim 6, Hanff ‘261 teaches the limitations set forth above. Hanff ‘261 further teaches at (Column 2/Lines 4-11, Fig. 1) its electromagnetic stirrer teeth extend perpendicular to a connecting yoke (meeting the limitation for a base connection).
Hanff ‘261 does not expressly teach one or more of the teeth having a greater length than one or more of the other teeth.
However, Folgero et al. ‘185 teaches an electromagnetic stirrer having teeth with varying lengths aligned with the curvature of a curved furnace (claim 1, Fig. 1). Folgero et al. ‘185 teaches at (Fig. 2) electromagnetic stirrer teeth extend perpendicular from a base connection, one or more of the teeth having a greater length than one or more of the other teeth, meeting the limitation of the instant Claim. Folgero et al. ‘185 further teaches at (Column 1 Lines 49-52) “The teeth of magnetic material and including parts 20 and 21 are brought forward to a narrow air gap between the stirrer 12 and the furnace bottom or side.”
Based on the teachings of Folgero et al. ‘185 at (claim 1, Figs. 1-2), it would have been obvious to one having ordinary skill in the art at the time of filing the invention that the perpendicularly extended teeth of Hanff ‘261 may be formed at different lengths to be brought into alignment to form a more narrow air gap and match the curvature of the furnace for which it electromagnetically stirs.
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Examiner Diagram 1 showing electromagnetic stirrer teeth arrangement in relation to a furnace surface with concavity and convexity.
Regarding Claims 7-9, Hanff ‘261 modified by Folgero et al. ‘185 teaches the limitations set forth above. Folgero et al. ‘185 teaches at (Fig. 2) electromagnetic stirrer teeth having teeth of varying lengths comporting with the surface curvature of a curved furnace.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to position an outermost tooth on one side of the three or more teeth that has a length greater than, shorter than, or the same as one or more of the other teeth in order to improve the electromagnetic path to the furnace based on the teachings of Folgero et al. ‘185 at (Column 1/Lines 58-64). See Examiner Diagram 1 above. As seen in the diagram, one of ordinary skill in the art at the time of filing the invention would understand that in order to form a uniform air gap between electromagnetic stirring teeth and a convex surface, the teeth on the ends would be shorter or longer than the teeth in the middle of such an arrangement based upon the concavity or convexity of the surface. Such changes would constitute changes in shape obvious to persons of ordinary skill in the art at the time of filing the invention. Generally, changes in shape will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such shape is critical. See MPEP 2141.01 IV. A, B, VI A, B, C.
Claims 11-12 are rejected under 35 U.S.C. 103 as being unpatentable over Hanff US 2875261 A as applied to 1-4, 13-14, 16, and 18 above, further in view of NPL Peel et al.
Regarding Claims 11-12 Hanff ‘261 teaches the limitations set forth above. Notwithstanding the 112(b) rejections above, Hanff ‘261 does not expressly teach the measurement of its air gap.
However, NPL Peel et al. teaches improvements to the effectiveness of electromagnetic stirring devices for creating magnetic flux within a furnace and teaches a 10mm (1cm) air gap between an inductor stirrer and the furnace surface (Fig. 2, Installation, 1195).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to minimize the distance between a magnetic device and its target surface in order to improve the magnetic effect and to unify the air gap created by an electromagnetic stirrer in relation to a furnace surface in order to improve magnetic flux and improve the efficiency of stirring of molten material within the furnace. One having ordinary skill in the art at the time of filing the invention would have looked to the art for a suitable narrow air gap between the electromagnetic stirrer and furnace to seek the teachings of NPL Peel et al. and form a 1cm air gap. The 1cm air gap lies within the range of the instant Claims. In cases where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Further, minimizing a non-zero air gap constitutes routine optimization as both Hanff ‘261 and NPL Peel et al. provide motivation to minimize the air gap and form a “closely adjacent” “narrow” spacing between the electromagnetic stirrer and furnace surface. See MPEP 2144.05 II.
It is noted here again that Applicant’s claim is to an electromagnetic stirrer, not to a curved furnace. Though an ‘air gap’ is a term of art, two points are needed to define a distance and only one point has been established. The limitations regarding position adjacent to a curved furnace is recited as intended use in Claim 1. As such, the electromagnetic stirrer of Hanff ‘261 meets the limitation of the instant claims 112-12 and it would have been obvious to one of ordinary skill in the art at the time of filing the invention to modify Hanff’261 by providing a 1 cm spacing between the stirrer of Hanff ‘261 and the surface of a curved furnace. See Hanff ‘261 e.g. at (Column 2/Lines 4-8).
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 1-4, 6-9, 11-14, 16, and 18 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-17 of U.S. Patent No.11,549,755. Although the claims at issue are not identical, they are not patentably distinct from each other because they overlap and encompass the limitations of the instant claims. U.S. Patent NO. 11,549,755 teaches an electromagnetic stirrer having a plurality of curved stays configured to match the curvature of a curved container wall with a less than 10 cm air gap. These claims overlap the limitations of each of the instant claims.
Response to Arguments
Applicant's arguments filed 07/07/2025 have been fully considered but they are not persuasive.
Applicant argues the cited references do not disclose minimizing the electromagnetic air gap between an electromagnetic stirrer and curved furnace. However, Applicant’s claims are to an electromagnetic stirring apparatus including three or more teeth. The prior art teaches such a device and it would have been obvious to one having ordinary skill in the art to configure the teeth of the electromagnetic stirring apparatus of Hanff ‘261 to be an equal distance from the surface of a curved furnace. Routine optimization of narrowing the gap between the surface of a curved furnace and curved electromagnetic stirring teeth is achieved by distancing the electromagnetic teeth at a uniform distance to the surface of the curved furnace and shaping the teeth to match the curvature of the furnace, thereby yielding the predictable result of increasing homogeneity of stirring. See MPEP 2144.05 II.
Hanff ‘261 e.g. at (Fig. 1, Column 1/Lines 40-45) teaches a long-standing practice of angling electromagnetic stirrer teeth to match the curvature of a curved furnace. One of ordinary skill in the art at the time of filing the invention would have been motivated by a desire to improve the charge of the electromagnetic stirrer and improve the electromagnetic path to a furnace and by a desire to improve homogeneity of electromagnetic stirring and efficiency of electromagnetic stirring of molten material within a furnace, to craft the teeth of the electromagnetic stirrer to match the curvature of a curved furnace. Generally, changes in shape will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such shape is critical. See MPEP 2141.01(a) I. Further, “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
US 2448009 A teaches an electromagnetic inductive heating apparatus having a 2cm air gap.
US 3704336 A teaches support means for an induction coil.
US 2960556 A teaches an electromagnetic stirring device for a curved furnace.
CN 102527283 A teaches a ring-shaped electromagnetic stirrer.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MORIAH S. SMOOT whose telephone number is (571)272-2634. The examiner can normally be reached M-F 8:30am - 5pm EDT.
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/Keith D. Hendricks/Supervisory Patent Examiner, Art Unit 1733
/M.S.S./Examiner, Art Unit 1733