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 .
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 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.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 18 April 2026 has been entered.
Response to Amendment
Applicant’s amendment filed on 18 April 2026 has been entered. Claims 16, 25 and 26 are amended. Claims 18 to 23 have been canceled. Claims 16 and 24-37 are pending. The amended claims and arguments have overcome each and every 112 rejection set forth in the previous office action. Therefore, the previous 112 rejections are hereby withdrawn.
Applicant’s arguments, with respect to the rejection(s) of Claims 16 and 18-37 rejected under 35 U.S.C. 112(a) and 112(b) have been fully considered and are persuasive.
Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Elorza Gomez (US 20130028749).
Applicant’s arguments with respect to the rejection(s) of Claims 16 and 18-37 rejected under 35 U.S.C. 112(a) and 112(b) have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Claim Objections
Claim 33 is objected to because of the following informalities:
In Claim 33, “the rotor blade designed” should be “the rotor blade is designed”.
Appropriate correction is required.
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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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.
Claims 16, 25, 26, and 33-37 are rejected under 35 U.S.C. 103 as being unpatentable over Elorza Gomez (US 20130028749) in view of Van Ness et al. (hereafter Van Ness – US 20160076380).
Claim 16 recites “a rotor blade.” Elorza Gomez teaches such a rotor blade, as will be shown.
Elorza Gomez teaches (Fig. 1) a rotor blade for placement in a gas channel of a turbomachine, the rotor blade comprising:
an airfoil 10, the airfoil, in relation to a flow in the gas channel, including a front edge 14 and a rear edge 13 downstream from the front edge, as well as a suction side 14 and a pressure side 15,
the airfoil being provided with an inclination toward the suction side over at least one section 23 of a radial airfoil height (para. 0022, Fig. 1),
wherein the inclination of the airfoil with respect to the suction side in a radially middle section of between 20% and 60% of the rotor blade airfoil height is greater than in a radially outer section (para. 0028-0029, Fig. 1).
However, as Elorza Gomez is directed to a stator blade, Elorza Gomez does not teach the inclination being set in such a way that during operation at an Aerodynamic Design Point a centrifugal force bending moment effectuating a centrifugal force on the airfoil is greater than a gas force bending moment acting on the airfoil due to the circulation around the airfoil in the gas channel.
Van Ness teaches (Figs. 1-4b) it is generally known that a rotor blade 80 design may be applied to either rotor blades or stator blades (para. 0043) in gas turbine engines.
MPEP 2143 I. D. teaches Applying a known technique to a known device (method, or product) ready for improvement to yield predictable results is obvious if there is (1) a finding that the prior art contained a "base" device (method, or product) upon which the claimed invention can be seen as an "improvement;" (2) a finding that the prior art contained a known technique that is applicable to the base device (method, or product); (3) a finding that one of ordinary skill in the art would have recognized that applying the known technique would have yielded predictable results and resulted in an improved system. In this case, Elorza Gomez teaches the base airfoil upon which the claimed invention can be seen as an improvement. Van Ness contains a known technique that is applicable to the base airfoil of Elorza Gomez since Van Ness teaches an airfoil design can be applied to any airfoil in a turbofan engine. Therefore, one of ordinary skill in the art could apply the airfoil of Elorza Gomez to any airfoil in a turbofan engine including a rotor blade. The results would be predictable since both references and Applicant’s invention are directed to airfoils in turbine engines, and the benefits of Elorza Gomez would apply to the rotor blade in a turbofan engine. Therefore, it would have been obvious for a person of ordinary skill in the art to apply the teachings of Van Ness to the airfoil of Elorza Gomez to have the blade is a rotor blade. As Elorza Gomez teaches the same inclination as Applicant’s invention, the modified rotor blade would result in the inclination being set in such a way that during operation at an Aerodynamic Design Point a centrifugal force bending moment effectuating a centrifugal force on the airfoil is greater than a gas force bending moment acting on the airfoil due to the circulation around the airfoil in the gas channel.
Regarding Claim 25, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 16 wherein the inclination of the airfoil with respect to the suction side in the radially middle section of the airfoil height is greater than in a radially inner section (see Fig. 1).
Regarding Claim 26, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 16.
Modified Elorza Gomez does not teach the inclination of the airfoil in a radially outer section deviates from the maximum inclination in the radially middle section by a maximum of 10%. Since Applicant has not disclosed that having rib extend at this specific maximum inclination deviation range solves any stated problem or is for any particular purpose and it appears that the maximum inclination deviation in the radially outer section of modified Elorza Gomez would perform equally well with the specified deviation inclination range as claimed by Applicant, it would have been an obvious matter of design choice to modify the maximum deviation range to fall within the claimed range.
Regarding Claim 33, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 16 wherein the rotor blade designed for a high-speed rotor having an An² of at least 2000 m/s² (modified Elorza Gomez’s blade would be usable in high speed rotor).
Regarding Claim 34, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) a turbine module for an aircraft engine comprising the rotor blade as recited in claim 16.
Regarding Claim 35, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) a geared turbofan engine comprising the rotor blade as recited in claim 16.
Regarding Claim 36, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the turbine module as recited in claim 34 designed as a low-pressure turbine module or a high-speed fan-driving turbine module, or designed to supply a cooling fluid to an outer shroud of the rotor blade, the cooling fluid being supplied from outside the rotor blade (modified Elorza Gomez’s blade would be useable in a turbine module).
Regarding Claim 37, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) a method for operating the rotor blade as recited in claim 16 comprising rotating the rotor blade with an An² of at least 2000 m/s² (modified Elorza Gomez’s blade would be usable in high speed rotor).
Claims 27 and 28 are rejected under 35 U.S.C. 103 as being unpatentable over Elorza Gomez in view of Van Ness, and further in view of Cole (US 5209643).
Regarding Claim 27, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 16.
However, modified Elorza Gomez does not teach the airfoil has a radially outwardly decreasing profile surface over at least one section of the airfoil height.
Cole teaches (Figs. 1-20) an aircraft assembly comprising rotor blades (10) that taper in the radial direction, wherein the airfoil has a radially outwardly decreasing profile surface (see Figs. 3-20).
Cole further teaches that providing such a rotor blades that taper in the radial direction, wherein the airfoil has a radially outwardly decreasing profile surface decreases in the radial direction reduces centrifugal loading and weight of the blade (col. 3, ln. 47-54).
It would have been obvious to apply the teachings of Cole to the rotor blade of modified Elorza Gomez to have the airfoil has a radially outwardly decreasing profile surface over at least one section of the airfoil height, as both references and Applicant’s invention are directed to rotor blades. Doing so would result in reduced centrifugal loading and weight, as recognized by Cole.
Regarding Claim 28, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 16.
However, modified Elorza Gomez does not teach the airfoil has a radially outwardly decreasing chord length in the at least one section of the airfoil height.
Cole teaches (Figs. 1-20) an aircraft assembly comprising rotor blades (10) that taper in the radial direction, wherein the airfoil has a radially outwardly decreasing chord length (see Figs. 3-20).
Cole further teaches that providing such a rotor blade that taper in the radial direction, wherein the airfoil has a radially outwardly decreasing chord length reduces centrifugal loading and weight of the blade (col. 3, ln. 47-54).
It would have been obvious to apply the teachings of Cole to the rotor blade of Martin to have the airfoil has a radially outwardly decreasing chord length, as both references and Applicant’s invention are directed to rotor blades. Doing so would result in reduced centrifugal loading and weight, as recognized by Cole.
Claims 29 is rejected under 35 U.S.C. 103 as being unpatentable over Elorza Gomez in view of Van Ness, and further in view of Tsypkaykin et al. (hereafter Tsypkaykin - US 20160312625).
Regarding Claim 29, Elorza Gomez, as modified with Van Ness in Claim 16 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 16.
However, modified Elorza Gomez does not teach an outer shroud situated radially outwardly at the airfoil, a single sealing fin being situated radially outwardly at the outer shroud.
Tsypkaykin teaches (Fig. 1, 2) a rotor blade comprising an airfoil (21) comprising an outer shroud (22) situated radially outwardly at the airfoil, a single sealing fin (40) being situated radially outwardly at the outer shroud.
Tsypkaykin further teaches such an outer shroud and fin results in minimising over-tip leakage flow and minimising the amount of material in the tip shroud to reduce the amount of material that has to pass through the narrow blade space in the mould during casting of the blade and to reduce centrifugal load on the blade aerofoil (see paragraph 0005).
It would have been obvious to apply the teachings of Tsypkaykin to the rotor blade of modified Elorza Gomez to have an outer shroud situated radially outwardly at the airfoil, a single sealing fin being situated radially outwardly at the outer shroud, as both references and Applicant’s invention are directed to rotor blades. Doing so would result in reduced over-tip leakage and centrifugal loading, as recognized by Tsypkaykin.
Claim 30 is rejected under 35 U.S.C. 103 as being unpatentable over Elorza Gomez in view of Van Ness, and further in view of Shi et al. (hereafter Shi – US 20190389777).
Regarding Claim 30, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 16 wherein at least the airfoil is made of a high temperature-resistant material.
However, modified Elorza Gomez does not teach wherein at least the airfoil is made of a high temperature-resistant material.
Shi teaches a rotor blade comprising an airfoil wherein at least the airfoil is made of a high temperature-resistant material (see Para. 0014).
Shi further teaches it is known to use a high temperature-resistant material in order to operate at high pressure and temperature typical of modern gas turbine engines.
It would have been obvious for a person having ordinary skill in the art to apply the teachings of Shi to the rotor blade of modified Elorza Gomez to have at least the airfoil is made of a high temperature-resistant material, as both references and Applicant’s invention are directed to rotor blades. Doing so would result in the airfoil being able to operate at high pressure and temperature, as recognized by Shi.
Claims 31 and 32 are rejected under 35 U.S.C. 103 as being unpatentable over Elorza Gomez in view of Van Ness, and further in view of Windprechtinger et al. (hereafter Windprechtinger - US 20160312625).
Regarding Claim 31, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 16.
However, modified Elorza Gomez does not teach a coating at least at the front edge.
Windprechtinger teaches (Fig. 1-4) a rotor blade comprising an airfoil (3) comprising a coating (10) at least at the front edge (see paragraph 0037) wherein the coating is a multilayer system that includes a ceramic layer and a metallic layer, the metallic layer being situated between the ceramic layer and the airfoil (see paragraph 0017-0018).
Windprechtinger further teaches such a coating protects the material of the blade against erosive wear (paragraph 0037).
It would have been obvious to apply the teachings of Windprechtinger to the rotor blade of modified Elorza Gomez to have a coating at least at the front edge, as both references and Applicant’s invention are directed to rotor blades. Doing so would result in protecting the material of the blade against erosive wear, as recognized by Windprechtinger.
Regarding Claim 32, Elorza Gomez, as modified with Van Ness in Claim 1 above, teaches (Elorza Gomez Fig. 1) the rotor blade as recited in claim 31 wherein the coating is a multilayer system that includes a ceramic layer and a metallic layer, the metallic layer being situated between the ceramic layer and the airfoil (see Windprechtinger paragraph 0017-0018).
Allowable Subject Matter
Claim 24 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The prior art does not teach wherein during operation the centrifugal force bending moment is at least 1.25 times the gas force bending moment.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANDREW BUI whose telephone number is (571) 272-0685. The examiner can normally be reached on 7:30 AM - 4:30 PM.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Courtney Heinle can be reached on (571) 270-3508. The fax phone number for the organization where this application or proceeding is assigned is (571) 273-8300.
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/ANDREW THANH BUI/Examiner, Art Unit 3745
/COURTNEY D HEINLE/Supervisory Patent Examiner, Art Unit 3745
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