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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 14 May 2026 has been entered.
Claim Rejections - 35 USC § 102/103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
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.
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 1-2 are rejected under 35 U.S.C. 102((a)(1)) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Smith et al. (US 2018/0283553).
With regard to claim 1, Smith discloses a piston ring (10 with 20) for use in an internal combustion engine that uses a hydrogen gas fuel (Examiner notes this is an intended use limitation in the preamble and is given little patentable weight. As the piston ring of Smith can physically be used in such it anticipates this limitation), wherein the piston ring comprises: a base material (10) comprising: i) a low alloy steel or a high alloy steel (as disclosed in claim 10, etc.) with no coating; (ii) a low alloy steel (as disclosed in claim 10, etc.) with a coating selected from the group consisting of a nitriding-treated coating (see para. [0005], etc. disclosing a nitriding treated coating), a triiron tetraoxide coating, and a manganese-based phosphate coating; or (iii) a high alloy steel (as disclosed in claim 10, etc.) with a nitriding-treated coating (see para. [0005], etc. disclosing a nitriding treated coating), wherein the piston ring also satisfies: Ra ≤5 µm, and Rv ≤ 14 µm (see para. [0025], Table 1, etc. disclosing an example embodiment with 0.3µm for Ra and 2.12 µm for Rz, which Examiner notes must essentially always be less than or equal to Rv based on how such is measured as Rv only measures the valley while Rz measures the entire peak to valley range) wherein: Ra (µm) is an arithmetic mean roughness of an upper surface of the piston ring (see para. [0025], etc., as well as this being a standard in the art value. Additionally notes that Applicant has not specified which surface is the upper surface and at least 12 can be considered an upper surface) and Rv (µm) is a maximum valley depth of an upper surface of the piston ring ((see para. [0025], etc., as well as this being a standard in the art value. Additionally notes that Applicant has not specified which surface is the upper surface and at least 12 can be considered an upper surface); wherein the piston ring has: a transverse rupture index, FP1, determined by a first transverse test conducted under a predetermined condition, and a post-corrosion transverse rupture index, FP2, determined by a second transverse test conducted under the predetermined condition after a corrosion test is conducted in which the piston ring is immersed in a 1% aqueous nitric acid solution for 30 minutes (Examiner notes that as these are defined as material property test of the piston ring, and as the piston ring of Smith is capable of undergoing these test it meets the claimed limitations); wherein a transverse rupture strength maintenance rate, FPS, wherein FPS = FP2/FP1 ≥ 0.75 (Examiner notes that such appears to be a material property and as Smith discloses several embodiments of materials identical to several of the large number of claimed materials/material combinations it would be considered to also disclose these claimed material properties/claimed limitations), wherein KDA is a first strength maintenance coefficient defined as KDA = FPS/Ra, and KDA ≥ 0.2 µm-1 (Examiner notes that such appears to be a material property and as Smith discloses several embodiments of materials identical to several of the large number of claimed materials/material combinations it would be considered to also disclose these claimed material properties/claim limitations). Though Smith is silent as to what the Ra and Rv values would be after a corrosion test, as Smith discloses several embodiments of materials identical to several of the large number of claimed materials/material combinations it would be considered to also disclose these claimed material properties/claim limitations, especially as Smith explicitly discloses much lower Ra and Rv values as such appear to be inherent properties of the material combination.
In the event that Applicant disagrees with Examiner’s interpretation of Smith (e.g. with respect to the after-corrosion values) it would have been considered obvious to one having ordinary skill in the art, at the time of filing, to have modified the device of Smith such that it has as low as possible arithmetic mean roughness (Ra) and maximum valley depth (Rv) and that Ra ≤5 µm and Rv ≤ 14 µm after such a corrosion test, as Examiner hereby takes Official Notice that the art is replete with examples of very smooth surfaces on piston rings and as some exceedingly low value must result in the claimed piston ring material properties of Ra ≤5 µm and Rv ≤ 14 µm after corrosion. Additionally see Applicant’s own para. [0023] that material selection and setting roughness low allows for such, and Applicant admission that it is common knowledge in the art for one of ordinary skill to know how to adjust Ra and Rv (see the 21 January 2026 arguments page 5 second to last paragraph).
As applicant has not traversed examiner’s assertion of official notice, the common knowledge or well-known in the art statement relied upon in examiner’s assertion of official notice is hereby taken to be admitted prior art in accordance with MPEP 2144.03.
With regard to claim 2, Smith discloses that a second strength maintenance coefficient, KDV(µm⁻¹), of the piston ring measured after the corrosion test, is defined as KDV(um⁻¹) = FPS/Rv, and KDV≥ 0.06 µm⁻¹ (Examiner notes that such appears to be a material property and as Smith discloses several embodiments of materials identical to several of the large number of claimed materials/material combinations it would be considered to also disclose these claimed material properties/claim limitations).
In the event that Applicant disagrees with Examiner’s interpretation of Smith (e.g. with respect to the after-corrosion values) it would have been considered obvious to one having ordinary skill in the art, at the time of filing, to have modified the device of Smith such that it has as low as possible arithmetic mean roughness (Ra) and maximum valley depth (Rv) and that thus KDV≥ 0.06 µm⁻¹ after such a corrosion test, as Examiner hereby takes Official Notice that the art is replete with examples of very smooth surfaces on piston rings and as some exceedingly low value must result in the claimed piston ring material properties of KDV≥ 0.06 µm⁻¹ after corrosion. Additionally see Applicant’s own para. [0023] that material selection and setting roughness low allows for such, and Applicant admission that it is common knowledge in the art for one of ordinary skill to know how to adjust Ra and Rv (see the 21 January 2026 arguments page 5 second to last paragraph).
As applicant has not traversed examiner’s assertion of official notice, the common knowledge or well-known in the art statement relied upon in examiner’s assertion of official notice is hereby taken to be admitted prior art in accordance with MPEP 2144.03.
Response to Arguments
Applicant's arguments filed 14 May 2026 have been fully considered but they are not persuasive.
Applicant’s arguments with respect to the prior 102/130 rejection are that the Ra and Rz values in Smith are not measured at the upper surface of the piston ring. This argument is not persuasive as Applicant has not claimed nor disclosed exactly what the upper surface must be and at least surface 12 of Smith can be considered an upper surface compared to other surfaces.
Applicant’s other argument that “a piston ring having sufficient fracture resistance strength against the problem of corrosive wear due to condensed water occurring in an internal combustion engine using a hydrogen gas fuel” is not persuasive as the instant claims do not recite such features. Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to NICHOLAS L FOSTER whose telephone number is (571)270-5354. The examiner can normally be reached M-F 9am-5pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Kristina Fulton can be reached at (571) 272-7376. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/NICHOLAS L FOSTER/Primary Examiner, Art Unit 3675
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