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
The Double Patenting rejection is withdrawn in view of the 3/12/2026 Terminal Disclaimer.
Applicant's arguments filed 3/12/2026, with respect to the 35 U.S.C. 103 rejections over Natori and Natori ‘639, have been fully considered but they are not persuasive. Applicant argues that Natori and Natori ‘639 do not teach scale removal using shot balls. However, the only requirement in the specification is that scale is removed without damaging the surface structure of the steel (see Spec., ¶ 86). In Natori and Natori ‘639, the scale is removed via pickling (¶ 152 and ¶ 129, respectively). There is no indication in the specification, and Applicant does not allege, that scale removal by pickling damages the surface structure of the steel or otherwise gives different results compared to the shot blasting scale removal described in the specification. For this reason, Applicant’s arguments are not persuasive and the rejections are maintained.
Terminal Disclaimer
The terminal disclaimer filed on 3/12/2026 disclaiming the terminal portion of any patent granted on this application which would extend beyond the expiration date of U.S. Application No. 18/722,296 has been reviewed and is accepted. The terminal disclaimer has been recorded.
Claim Rejections - 35 USC § 102/103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-5 and 12 are rejected under 35 U.S.C. 102(a)(1)/(a)(2) as being anticipated by, or, in the alternative, under 35 U.S.C. 103 as being unpatentable over Natori et al. (US 2022/0021248).
Regarding claims 1-5, Natori discloses a non-oriented electrical steel sheet having the following compositions (see Table 1, Ex. M; and ¶¶ 14&19) as compared to the claimed composition, in wt%:
Claim 1
Natori, Ex. M
Natori, ¶¶ 14&19
Si
2.0%-6.5%
3.1%
2.5%-4.0%
Al
0.1%-1.3%
0.81%
0.0005%-1.50%
Mn
0.3%-2.0%
1.9%
0.05%-2.0%
Cr
0.005%-0.06%
0.06%
≤0.10%
Fe
Balance
Balance
Balance
Claim 2
Sn
≤0.06%
0.02%
≤0.20% (¶ 19)
Sb
≤0.06%
-
-
Claim 3
C, N, S, Ti, Nb, V
≤0.005% each
C: 0.0046%, S: 0.0027%, Ti: 0.0013%
≤0.0015% C; ≤0.0030% S, Ti
Claim 4
Cu
0.01%-0.2%
0.03%
≤0.10% (¶ 19)
P
≤0.100%
0.015%
≤0.080% (¶ 19)
B
≤0.002%
-
-
Mo
≤0.01%
-
-
Mg
≤0.005%
-
≤0.005% (¶ 19)
Zr
≤0.005%
-
-
Example M lies within the claimed ranges, thereby anticipating the claimed composition. In the alternative, Natori teaches the general composition of the steel sheet which overlaps the claimed composition, creating a prima facie case of obviousness.
See MPEP 2144.05 I. Additionally, Natori teaches an insulating coating is formed on the steel sheet (¶ 160).
Natori does not expressly disclose the steel sheet satisfies the claimed Formulas 1 and 2. However, the instant specification establishes that scale on the steel sheet must be removed to allow formation of a Cr oxide layer on the surface in order to control diffusion of Mn from the steel sheet into the insulating coating during the stress relief annealing step (see Spec., ¶ 85 of corresponding PGPub). Thus, the [Mn coating film] amount is within the range of 2.0%-10.0%wt following stress relief annealing assuming a starting Mn amount in the insulating coating of less than 0.01%wt (see Spec., ¶¶ 68-71 of corresponding PGPub). The instant specification also establishes that a [Mn50] value is within 0.10%wt of the overall Mn concentration in the steel sheet (see Spec., Tables 2&3), and the stress relief annealing is performed at a temperature of 700°C-850°C for 10-300 minutes (see Spec., ¶ 13 of corresponding PGPub).
Natori teaches a Cr amount which lies within or is substantially similar to the Cr amount in the claimed steel sheet. Scale on the steel sheet is removed (¶ 152) prior to forming the insulating coating. The insulating coating of Natori does not contain Mn (see ¶ 160). Thus, it is 0%wt before stress relief annealing and the prior art steel sheet satisfies Formula 1 because [Mn coating film]/[Mn50] is necessarily zero. Natori also teaches the stress relief annealing for Ex. M is performed at 800°C for 60 minutes (¶ 163), which lies within the parameters for making the claimed invention. In the alternative, Natori generally teaches performing the stress relief annealing at a temperature of 750°C-900°C for 30-300 minutes (¶ 145). Based on the substantial similarities between the making of the steel sheet of Natori and that of making the claimed invention, one of ordinary skill in the art would expect the prior art steel sheet to have a Cr oxide layer which controls Mn diffusion into the insulating coating, thereby resulting in a [Mn coating film] amount within the range of 2.0%-10.0%, absent objective evidence to the contrary. See MPEP 2112. Thus, one of ordinary skill in the art would expect the [Mn coating film]/[Mn50] after stress relief annealing to be within the range of 1.1-5 for Ex. M, which lies within the claimed range. Alternatively, given the amount of Mn in the steel sheet of Natori, the prior art implicitly teaches an overlapping range for Formula 2, creating a prima facie case of obviousness. See MPEP 2144.05 I.
Regarding claim 12, Natori discloses motor core made from a non-oriented electrical steel sheet (¶¶ 17-20). The non-oriented electrical steel sheet of Natori has the following compositions (see Table 1, Ex. M; and ¶ 14), as compared to the claimed composition, in wt%:
Claim 12
Ex. M
Natori, ¶ 14
Si
2.0%-6.5%
3.1%
2.5%-4.0%
Al
0.1%-1.3%
0.81%
0.0005%-1.50%
Mn
0.3%-2.0%
1.9%
0.05%-2.0%
Cr
0.005%-0.06%
0.06%
≤0.10%
Fe
Balance
Balance
Balance
Example M lies within the claimed ranges, thereby anticipating the claimed composition. In the alternative, Natori teaches the general composition of the steel sheet which overlaps the claimed composition, creating a prima facie case of obviousness.
See MPEP 2144.05 I. Additionally, Natori teaches forming an insulating coating on the steel sheet (¶ 160).
Natori teaches the motor core comprises a rotor and a stator made from the same steel sheet (¶¶ 3, 17-20), where the stator undergoes stress relief annealing but not the rotor (see ¶¶ 138&150). Natori does not expressly disclose the steel sheet of the rotor or stator satisfy the claimed Formulas 1 or 2, respectively. However, the insulating coating of Natori does not necessarily contain Mn (see ¶ 160). Thus, [Mn coating film] is 0%wt and the rotor of the prior art motor core implicitly satisfies Formula 1 because [Mn coating film]/[Mn50] must also be zero when stress relief annealing is not performed.
Regarding the stator, the instant specification establishes that scale on the steel sheet must be removed to allow formation of a Cr oxide layer on the surface in order to control diffusion of Mn from the steel sheet into the insulating coating during the stress relief annealing step (see Spec., ¶ 85 of corresponding PGPub). Thus, the [Mn coating film] amount is within the range of 2.0%-10.0%wt following stress relief annealing assuming a starting Mn amount in the insulating coating of less than 0.01%wt (see Spec., ¶¶ 68-71 of corresponding PGPub). The instant specification also establishes that the [Mn50] value is within 0.10%wt of the overall Mn concentration in the steel sheet (see Spec., Tables 2&3), and the stress relief annealing is performed at a temperature of 700°C-850°C for 10-300 minutes (see Spec., ¶ 13 of corresponding PGPub).
Natori teaches a Cr amount which lies within or is substantially similar to the Cr amount in the claimed steel sheet. Scale on the steel sheet is removed (¶ 152) prior to forming the insulating coating. Natori also teaches the stress relief annealing for Ex. M is performed at 800°C for 60 minutes (¶ 163), which lies within the parameters for making the claimed invention. In the alternative, Natori generally teaches performing the stress relief annealing at a temperature of 750°C-900°C for 30-300 minutes (¶ 145). Based on the substantial similarities between the making of the steel sheet of Natori and that of making the claimed invention, one of ordinary skill in the art would expect the prior art stator has a Cr oxide layer which controls Mn diffusion into the insulating coating, thereby resulting in a [Mn coating film] amount within the range of 2.0%-10.0%, absent objective evidence to the contrary. See MPEP 2112. Thus, one of ordinary skill in the art would expect the [Mn coating film]/[Mn50] after stress relief annealing to be within the range of 1.1-5 for Ex. M, which lies within the claimed range. Alternatively, given the amount of Mn in the steel sheet of Natori, the prior art implicitly teaches an overlapping range for Formula 2, creating a prima facie case of obviousness. See MPEP 2144.05 I.
Claims 1-5 and 12-14 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by, or, in the alternative, under 35 U.S.C. 103 as being unpatentable over Natori et al. (US 2025/0022639) (herein after Natori ‘639).
Regarding claims 1-5, Natori ‘639 discloses a non-oriented electrical steel sheet having the following compositions (see Table 1, Ex. C; and ¶¶ 9-29) as compared to the claimed composition, in wt%:
Claim 1
Ex. C
Natori ‘639, ¶¶ 9-29
Si
2.0%-6.5%
3.7%
3.2%-6.5%
Al
0.1%-1.3%
0.20%
≤1.0%
Mn
0.3%-2.0%
1.0%
0.05%-3.5%
Cr
0.005%-0.06%
0.05%
≤0.10%
Fe
Balance
Balance
Balance
Claim 2
Sn
≤0.06%
-
≤0.10% (¶ 29)
Sb
≤0.06%
0.01%
≤0.10% (¶ 29)
Claim 3
C, N, S, Ti, Nb, V
≤0.005% each
C: 0.0014%, S: 0.0017%, Ti: 0.0017%, V: 0.0009%
≤0.0030% C, S, Ti; ≤0.0010% V
Claim 4
Cu
0.01%-0.2%
0.06%
≤0.10% (¶ 29)
P
≤0.100%
0.011%
0.005%-0.10%
B
≤0.002%
0.0002%
≤0.001%
Mo
≤0.01%
0.021%
≤0.03%
Mg
≤0.005%
-
≤0.005%
Zr
≤0.005%
-
-
Example C lies within the claimed ranges, thereby anticipating the claimed composition. In the alternative, Natori ‘639 teaches the general composition of the steel sheet which overlaps the claimed composition, creating a prima facie case of obviousness.
See MPEP 2144.05 I. Additionally, Natori ‘639 teaches an insulating coating is formed on the steel sheet (¶ 9).
Natori ‘639 does not expressly disclose the steel sheet satisfies the claimed Formulas 1 and 2. However, the instant specification establishes that scale on the steel sheet must be removed to allow formation of a Cr oxide layer on the surface in order to control diffusion of Mn from the steel sheet into the insulating coating during the stress relief annealing step (see Spec., ¶ 85 of corresponding PGPub). Thus, the [Mn coating film] amount is within the range of 2.0%-10.0%wt following stress relief annealing assuming a starting Mn amount in the insulating coating of less than 0.01%wt (see Spec., ¶¶ 68-71 of corresponding PGPub). The instant specification also establishes that the [Mn50] value is within 0.10%wt of the overall Mn concentration in the steel sheet (see Spec., Tables 2&3), and the stress relief annealing is performed at a temperature of 700°C-850°C for 10-300 minutes (see Spec., ¶ 13 of corresponding PGPub).
Natori ‘639 teaches a Cr amount which lies within or is substantially similar to the Cr amount in the claimed steel sheet. Scale on the steel sheet is removed (¶ 129) prior to forming the insulating coating. The insulating coating of Natori ‘639 does not necessarily contain Mn (see ¶ 28; see also Ex. 10-C, 11-C of Table 2). Thus, it is less than 0.01%wt and the prior art steel sheet satisfies Formula 1 before stress relief annealing because [Mn coating film]/[Mn50] is zero. Natori ‘639 also teaches the stress relief annealing for Ex. C is performed at 800°C for 120 minutes (¶ 131), which lies within the parameters for making the claimed invention. In the alternative, Natori ‘639 generally teaches performing the stress relief annealing at a temperature of 750°C-900°C for 30-300 minutes (¶ 125). Based on the substantial similarities between the making of the steel sheet of Natori ‘639 and that of making the claimed invention, one of ordinary skill in the art would expect the prior art steel sheet to have a Cr oxide layer which controls Mn diffusion into the insulating coating, thereby resulting in a [Mn coating film] amount within the range of 2.0%-10.0%, absent objective evidence to the contrary. See MPEP 2112. Thus, one of ordinary skill in the art would expect the [Mn coating film]/[Mn50] after stress relief annealing to be within the range of 2.2-9.1 for Ex. C, which lies within the claimed range. Alternatively, given the amount of Mn in the steel sheet of Natori ‘639, the prior art implicitly teaches an overlapping range for Formula 2, creating a prima facie case of obviousness. See MPEP 2144.05 I.
Regarding claim 12, Natori ‘639 discloses motor core made from a non-oriented electrical steel sheet (¶ 104). The non-oriented electrical steel sheet of Natori ‘639 has the following compositions (see Table 1, Ex. C; ¶¶ 9-27) as compared to the claimed composition, in wt%:
Claim 12
Ex. C
Natori, ¶¶ 9-27
Si
2.0%-6.5%
3.7%
3.2%-6.5%
Al
0.1%-1.3%
0.20%
≤1.0%
Mn
0.3%-2.0%
1.0%
0.05%-3.5%
Cr
0.005%-0.06%
0.05%
≤0.10%
Fe
Balance
Balance
Balance
Example C lies within the claimed ranges, thereby anticipating the claimed composition. In the alternative, Natori ‘639 teaches the general composition of the steel sheet which overlaps the claimed composition, creating a prima facie case of obviousness. See MPEP 2144.05 I. Additionally, Natori ‘639 teaches an insulating coating is formed on the steel sheet (¶ 9).
Natori ‘639 teaches the motor core comprises a rotor and a stator made from the same steel sheet, where the rotor does not undergo stress relief annealing (¶ 104). Natori ‘639 does not expressly disclose the steel sheet of the rotor and stator satisfy the claimed Formulas 1 or 2, respectively. However, the insulating coating of Natori ‘639 does not necessarily contain Mn (see ¶ 28; see also Ex. 10-C, 11-C of Table 2). Thus, [Mn coating film] is 0%wt and the rotor of the prior art motor core implicitly satisfies Formula 1 because [Mn coating film]/[Mn50] must also be zero when stress relief annealing is not performed.
Regarding the stator, the instant specification establishes that scale on the steel sheet must be removed to allow formation of a Cr oxide layer on the surface in order to control diffusion of Mn from the steel sheet into the insulating coating during the stress relief annealing step (see Spec., ¶ 85 of corresponding PGPub). Thus, the [Mn coating film] amount is within the range of 2.0%-10.0%wt following stress relief annealing assuming a starting Mn amount in the insulating coating of less than 0.01%wt (see Spec., ¶¶ 68-71 of corresponding PGPub). The instant specification also establishes that the [Mn50] value is within 0.10%wt of the overall Mn concentration in the steel sheet (see Spec., Tables 2&3), and the stress relief annealing is performed at a temperature of 700°C-850°C for 10-300 minutes (see Spec., ¶ 13 of corresponding PGPub).
Natori ‘639 teaches a Cr amount which lies within or is substantially similar to the Cr amount in the claimed steel sheet. Scale on the steel sheet is removed (¶ 129) prior to forming the insulating coating. Natori ‘639 also teaches the stress relief annealing for Ex. C is performed at 800°C for 120 minutes (¶ 131), which lies within the parameters for making the claimed invention. In the alternative, Natori ‘639 generally teaches performing the stress relief annealing at a temperature of 750°C-900°C for 30-300 minutes (¶ 125). Based on the substantial similarities between the making of the steel sheet of Natori ‘639 and that of making the claimed invention, one of ordinary skill in the art would expect the prior art stator has a Cr oxide layer which controls Mn diffusion into the insulating coating, thereby resulting in a [Mn coating film] amount within the range of 2.0%-10.0%, absent objective evidence to the contrary. See MPEP 2112. Thus, one of ordinary skill in the art would expect the [Mn coating film]/[Mn50] of the stator after stress relief annealing to be within the range of 2.2-9.1 for Ex. C, which lies within the claimed range. Alternatively, given the amount of Mn in the steel sheet of Natori ‘639, the prior art implicitly teaches an overlapping range for Formula 2, creating a prima facie case of obviousness. See MPEP 2144.05 I.
Regarding claims 13-14, Natori ‘639 teaches the rotor and stator are formed from the same non-oriented electrical steel sheet (see ¶¶ 48, 104-105). Thus, they are from the same coil, and one of ordinary skill in the art would not expect a substantial compositional difference to be present when both rotor and stator are punched from the same steel sheet, whose composition is presumed to be uniform, absent objective evidence to the contrary. See MPEP 2112.
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.
Claims 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Natori et al. (US 2022/0021248), as applied to claim 12, further in view of Murakawa et al. (US 2024/0154472).
Regarding claims 13-14, the limitations of claim 1 have been addressed above. Natori does not expressly disclose the recited limitations of claims 13-14. Murakawa teaches making the rotor and stator sheets for a motor core from the same electrical steel sheet (¶¶ 142-143, see also Tables 3&4). It would have been obvious at the effective time of filing for one of ordinary skill in the art to use the same electrical steel sheet to make both the rotor and stator sheets for a motor core as one of ordinary skill in the art can readily appreciate this increases production efficiency by reducing the number of steps required to make a motor core. Since both rotor and stator sheets come from the same electrical steel sheet, they are from the same coil, and one of ordinary skill in the art would not expect a substantial compositional difference to be present when both rotor and stator are punched from the same steel sheet, whose composition is presumed to be uniform, absent objective evidence to the contrary. See MPEP 2112.
Conclusion
THIS ACTION IS MADE FINAL. 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 XIAOBEI WANG whose telephone number is (571)270-5705. The examiner can normally be reached M-F 8AM-5PM EST.
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, Humera Sheikh can be reached at 571-272-0604. 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.
/XIAOBEI WANG/Primary Examiner, Art Unit 1784
Prosecution Insights