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 .
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 1-8 are rejected under 35 U.S.C. 103 as being unpatentable over JP 2012-077333 Senda et al in view of JP 2016-211069 Hiraoka et al further in view of US 2020/0040439 Umehara et al.
Regarding claim 1, Senda teaches a steel component comprising a nitride compound layer (paragraph 0001) with a thickness and a hardened layer in an order from a steel surface to steel inside (paragraph 0038),
wherein the hardened layer has a hardness of HV600 or more at a position of 50 microns inward from the steel surface, a hardness of HV400 or more at a position from the steel surface to the steel inside of 400 microns (Table 3 Example 16 teaching a surface hardness of 875 HV with an effective hardening layer depth of 417 microns, and paragraph 0093 teaching that the effective hardening layer depth is the thickness of the layer that is at least 550 HV),
wherein the hardnesses are measured by Vickers hardness meter in accordance with JIS Z2244 with a test load of 2.9N (paragraph 0092).
Senda does not explicitly teach that the hardness at a depth of 600 microns is at least 250 HV. However, Senda does teach that the hardness before the nitriding treatment is 269 HV (Table 3 Example 16 and paragraph 0093). Senda does not explicitly teach the depth at which that hardness occurs. However, it is reasonable to expect that the hardening treatment (nitriding treatment) would only increase hardness, not decrease it. Therefore, the Examiner is taking the position that the hardness at a depth of 600 microns, as well as in the remainder of the steel component, is at least 269 HV. Senda’s translated Table 3 has been reproduced here for
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convenience.
Senda does not explicitly teach that the hardness is measured at six points and averaged. However, the method of measuring the claimed hardness is not considered to structurally limit the claim. Note that Applicant has not provided evidence that the claimed method of measuring hardness results in a structural difference between Applicant’s component and the taught component; see MPEP 2113. As such, Senda is considered to read on the claimed hardness regardless of the measuring technique.
Senda does not teach the thickness of the nitride compound layer or the presence of a porous layer, but does that the inventive product is formed by gas nitriding (paragraph 0091). Hiraoka teaches a nitride steel component formed by gas nitriding (paragraph 0001) where the thickness of the nitride compound layer is 13-30 microns (abstract). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to include the compound layer thickness of Hiraoka in the product of Senda because this produces a product with improved fatigue strength and improved wear resistance (abstract).
Neither Senda nor Hiraoka teaches the porous layer thickness. Umehara teaches a nitrided steel component formed by gas nitriding (paragraph 0065), where the thickness of a porous layer on an outermost surface of the nitride compound layer is 3 microns or less (paragraphs 0072-0076 teaching that pores are undesirable and therefore kept to a minimum in the top 3 microns of the compound layer),
wherein the thickness of the porous layer is defined as a maximum depth of a continuous pore aggregate from the surface (figure 4), measured on a cross-section corroded with a 3% Nital solution, observed by optical microscopy at 500 magnifications (paragraph 0065), and taken at a maximum at the measured point (figure 4).
Umehara does not explicitly teach measuring the maximum depth at three points to determine thickness. However, the method of measuring the claimed thickness is not considered to structurally limit the claim. Note that Applicant has not provided evidence that the claimed method of measuring thickness results in a structural difference between Applicant’s component and the taught component; see MPEP 2113. As such, Umehara is considered to read on the claimed thickness regardless of the measuring technique.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to include the pore layer thickness and corresponding measuring method of Umehara in the product of Hiraoka because pores becomes starting points for pitting and bending fatigue, such that this layer should be minimized (paragraph 0073).
A pore layer thickness of 3 microns (Umehara 0072-0076) in the compound layer of 13-30 microns (Hiraoka abstract) is 23% to 10% of the thickness of the compound layer.
Regarding claim 2, Senda teaches that the steel component is a toothed component (paragraph 0033) and has the compound layer at least in a surface layer of a tooth portion (paragraph 0001).
Regarding claim 3, 5 and 7, Senda in view of Hiraoka and Umehara teaches that the thickness of the porous layer on the outermost surface of the nitride compound layer is 1.3 to 3.0 microns or less (Hiraoka abstract teaching a compound layer 13 to 30 microns in thickness, and Umehara 0020 teaching a porous layer of 10% or less of the compound layer).
“In the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists,” (MPEP 2144.05 Section I). Therefore, absent evidence of criticality, the taught range of 1.3 to 3.0 microns or less reads on the claimed range of 1.0 microns or more (claim 3) and 1.3 microns or less (claims 5 and 7).
Regarding claims 4, 6 and 8, Senda teaches that the steel component is a toothed component (paragraph 0033) and has the compound layer at least in a surface layer of a tooth portion (paragraph 0001).
Response to Arguments
Applicant’s arguments regarding the hardness at a 600 micron depth have been considered but are moot because of the modified explanation above.
Applicant's arguments filed February 17, 2026, have been fully considered but they are not persuasive.
Applicant argues that the prior art does not teach the measurement. However, both Senda and Umehara teach portions of the measuring methods. Additionally, Applicant has not shown that the measuring method structurally limits the claimed component as discussed above.
Applicant argues that Umehara teaches away from a thick compound layer. However, Umehara is being used to modify Hiraoka, not the other way around. Umehara’s desire for thin layers does not affect the pore layer thickness teaching.
Applicant argues that Examiner has used hindsight in combining Hiraoka and Umehara. However, Umehara explicitly teaches a reason to want a minimized pore layer thickness. This combination does not destroy Hiraoka as Umehara’s relatively thinner layer is not being imported into Hiraoka.
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 Megha M Gaitonde whose telephone number is (571)270-3598. The examiner can normally be reached Monday-Friday 8:30 am to 5 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, Frank Vineis can be reached on 571-270-1547. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MEGHA M GAITONDE/Primary Examiner, Art Unit 1781
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