DETAILED ACTION
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 1-3 and 5-11 are rejected under 35 U.S.C. 103 as being unpatentable over Marsal (US 20180036914) in view of Johnston (US 4,976,587).
As to claim 1, Marsal teaches a method for manufacturing a turbomachine blade (Fig. 8). Marsal teaches a first fiber preform weaving preparation step (Fig. 6, item 10) which forms a spar with a core (Fig. 1, item 1). Marsal teaches arranging the first fiber preform in a mold ([0051]), performing a first resin injection step, and polymerization/curing step ([0052]) which would result in vitrification of the resin. Marsal teaches positioning a second fiber preform (4) around the core of the spar (Fig. 1) and performing a second resin injection step (Fig. 6, item 51) by injecting the resin into the preform of the body of the blade ([0051]). A second polymerization/curing step after the second resin injection step would have been obvious in order to cure the polymer ([0052]) into the desired blade structure (Fig. 8).
Marsal does not specifically teach a partial polymerization step performed on the spar.
Johnston teaches a method for manufacturing a blade which includes a step of partial curing of a spar (10:42-43) which would necessarily lead to partial vitrification of a first resin, which is then incorporated directly into an assembled blade (10:44-45) and curing is then completed (12:56).
It would have been prima facie obvious to one of ordinary skill in the art prior to filing to incorporate the Johnston partial polymerization step into Marsal motivated by (a) preserving the Marsal preform in a flexible state (using partial polymerization) during the placement of the Marsal first fiber preform in the Marsal second resin injection step, or (b) improving the bond between the resin in the first resin injection step and second resin injection step. A reasonable expectation of success would be present in light of the similar structure of the Johnston and Marsal processes.
As to claims 2, 3, and 10, Marsal teaches a first resin and second resin not disclosed as being different. Although Marsal is silent to epoxy, Johnston teaches that a blade may be formed from an epoxy resin (12:4-5) which is a thermosetting resin, as an obvious interchangeable substitute resin.
As to claim 5, Johnston teaches that resin can be partially cured (partial polymerization) by applying heat to an unspecified temperature (12:56-57), and therefore the particular partial polymerization temperature represents a result effective variable necessary to produce the desired result. One would have arrived at the claimed partial polymerization temperature below the nominal curing temperature by optimizing the curing temperature. Alternatively, Johnston teaches that curing can be completed at room temperature for some resins (12:57) which would obviously below the nominal polymerization temperature.
As to claims 6 and 7, Marsal teaches a first resin and second resin not disclosed as being different. When the first resin and second resin are the same, the nominal polymerization temperature for the two resins would be the same and have a difference of 0°C.
As to claims 8, 9, and 11, Marsal teaches spar and blade fiber-containing preforms which form a composite blade after incorporating resin.
Claims 4, 12, and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Marsal (US 20180036914) in view of Johnston (US 4,976,587), and further in view of Hartman (US 20060089068).
As to claim 4, 12, and 13, Marsal and Johnston are silent to partial polymerization to a crosslinking ratio higher than or equal to 0.7.
Hartman provides a composite article with an epoxy or polyester binder ([0011]) which has a degree of cure of between 50-100 percent ([0012]).
It would have been prima facie obvious to incorporate the Hartman degree of cure into the Marsal/Johnston process because Johnston teaches/suggests at least partial polymerization without discussion of a particular level or degree of cure, and Hartman provides a partial polymerization or degree of cure interpreted to be within the scope of Johnston. There would be a reasonable expectation of success because the Hartman degree of cure would prevent resin from flowing out of the composite.
Response to Arguments
Applicant's arguments filed May 15, 2026 have been fully considered but they are not persuasive.
On page 6, Applicant argues one would not have found motivation to modify Marsal’s turbomachine blades with features from the Johnston process because Johnston is directed to the “unrelated technical field” of wind turbine blades. Applicant further argues that the Johnston box spar (36) is for supporting gravitationally induced rotational loads in a wind turbine, and that partial curing in wind rotor blades would not be understood to have the same meaning as partial curing in the technical field of turbine engine blades. On page 7, Applicant argues the present invention provides partial vitrification which permits the first resin to bind together with the second resin during complete polymerization. The arguments directed to claims 2-11 do not appear to be substantive.
The Examiner respectfully disagrees. The Examiner maintains the position that these references are both in the Applicant’s field of endeavor even if Johnston teaches a wind turbine rotor blade. Both references provide a structure which interacts with air, and any different induced rotational loads in the references do not separate these references into a different field of endeavor. The Johnston reference teaches that two curing options are possible: partial curing and bonding (10:42-46), or alternatively, sanding and solvent wiping prior to bonding (10:46-52). The Examiner takes the position that partial vitrification which enables bonding/bonding with a second resin is taught by Johnston, and would have been obvious for use with Marsal.
Pertinent Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Graff (US 5,222,297), Anderson (US 20160032939), Cook (US 5,392,514), Carvalho (US 20100290913), and Coupe (US 2013/0017093) are pertinent to the claimed invention.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 MATTHEW J DANIELS whose telephone number is (313)446-4826. The examiner can normally be reached Monday-Friday, 8:30-5:00 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, Christina Johnson can be reached at 571-272-1176. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MATTHEW J DANIELS/Primary Examiner, Art Unit 1742
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