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 Objections
Applicant is advised that should claim 2 or 9 be found allowable, claims 6 and 13 will be objected to under 37 CFR 1.75 as being a substantial duplicate thereof. When two claims in an application are duplicates or else are so close in content that they both cover the same thing, despite a slight difference in wording, it is proper after allowing one claim to object to the other as being a substantial duplicate of the allowed claim. See MPEP § 608.01(m).
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-2, 5-9, 12-16, 19-20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. The original disclosure fails to teach the “single undercut groove … is located entirely upstream, forward, and adjacent to a leading edge of a blade shroud of each rotor blade”. The specification discloses that the groove may be upstream and adjacent to a leading edge (para 28), but does not teach “entirely”. The figures show a cross-section at one circumferential location, and therefore does not show if the groove is upstream of the leading edge at any other circumferential locations.
The original disclosure fails to teach the vane outer shroud comprising a single groove. The amendment introduces an exclusionary limitation, "a single groove", which excludes other grooves in the vane outer shroud. However, “any negative limitation or exclusionary proviso must have basis in the original disclosure” and "the mere absence of a positive recitation is not basis for an exclusion" (MPEP 2173.05(i)). For example, the specification and drawings fail to disclose whether there are multiple grooves spaced around the circumference of the outer shroud.
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.
Claim(s) 1-2, 6, 8-9, 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 2011/0085892 (John) in view of US 4662820 (Sasada).
Regarding claim 1, 8, John teaches a gas turbine engine (para 2, 23) comprising: a vane outer shroud for a gas turbine engine, the vane outer shroud comprising: a plurality of vanes coupled to the vane outer shroud (para 2); an outer shroud (Fig 7 or 8; shroud 30); an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane (para 2; Fig 7 or 8; rotor blades 20); and a single undercut groove (groove formed by wall 71 and 100), wherein the single undercut groove is formed radially outward into the vane outer shroud and is located entirely upstream, forward, and adjacent to a leading edge of a blade shroud of each rotor blade (Fig 7 or 8), and wherein the single undercut groove is configured to recirculate generate a local aerodynamic recirculation of air and/or gas radially inward toward the rotor blade, wherein the local aerodynamic recirculation forms a barrier that discourages air and/or gas from leaking through a blade tip of the rotor blade (para 1-7, 25-30; the “vortex” is recirculated flow radially inward 75, 85 toward the rotor blade – see Fig 1; effective flow area E is therefore reduced relative to area A – e.g. flow is discouraged).
John teaches a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane as discussed above. However, even if John did not teach a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane, Sasada teaches a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane (Fig 5, col 5 ll. 16-30; vanes 2, blades 6, vane outer shroud 1). It would have been obvious to one of ordinary skill in the art at the time of the invention to provide a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane in order to deliver fluid to the turbine, as taught by Sasada. It has been held that combining or simple substitution of prior art elements according to known methods to yield predictable results renders the limitation obvious (see MPEP 2141 (III)). In this case, a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane, yields predictable results (passage of fluid from the vanes to the blades).
Regarding claim 2, 6, 9, 13, John in view of Sasada teaches a depth of the single undercut groove is greater than half of a width of the single undercut groove (John Fig 7 or 8; depth is the radial dimension of the groove, from the bottom of wall 72 to the radially outermost point of the groove; width is the axial dimension – from left to right in the figure, from wall 71 to wall 100; the depth is greater than half of the width).
Regarding claim 7, 14, John in view of Sasada teaches the single undercut groove is configured to have a shape and wherein the shape is at least one of a semicircular shape, a V shape, or a spiral, hook-shape (John Fig 7 or 8; semicircular shape).
Claim(s) 5, 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 2011/0085892 (John) in view of US 4662820 (Sasada), and further in view of US 2014/0154061 (Kuwamura).
Regarding claims 5, 12, John in view of Sasada fails to teach a depth of the single groove is half of a width of the single groove. However, Kuwamura teaches a groove upstream, forward and adjacent to a leading edge of a blade shroud, wherein a depth of the groove is half of a width of the single groove (Fig 2, para 60-62, Formula 1; “height” is the depth; D/W may be 0.5). It would have been obvious to one of ordinary skill in the art at the time of the invention to make the depth of the single groove is half of a width of the single groove, as taught by Kuwamura. It has been held that combining or simple substitution of prior art elements according to known methods to yield predictable results renders the limitation obvious (see MPEP 2141 (III)). In this case, making the depth of the single groove is half of a width of the single groove yields predictable results (sealing, recirculation).
Claim(s) 7, 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 2011/0085892 (John) in view of US 4662820 (Sasada), and further in view of US 2022/0186842 (Daniels).
Regarding claim 7, 14, John in view of Sasada teaches the groove is configured to have a shape and wherein the shape is at least one of a semicircular shape, a V shape, or a spiral, hook-shape as discussed above. However, even if John was not construed as teaching a semi-circular shape, Daniels teaches a groove in an outer shroud that has a semicircular shape (para 21, 94-95). It would have been obvious to one of ordinary skill in the art at the time of the invention to make the shape a semicircular shape, as taught by Daniels. It has been held that combining or simple substitution of prior art elements according to known methods to yield predictable results renders the limitation obvious (see MPEP 2141 (III)). In this case, making the shape a semicircular shape, yields predictable results (reducing leakage).
Claim(s) 15-16, 19-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 11680542 (Davis) in view of US 2011/0085892 (John) and US 4662820 (Sasada).
Regarding claim 15, Davis teaches an aircraft comprising a gas turbine engine (Fig 1, col 1 ll. 14-30), the gas turbine engine comprising a plurality of vanes and a plurality of rotor blades (depicted alternating vanes and blades of the low pressure turbine 40).
Davis fails to teach the vane outer shroud and groove. However, John teaches a gas turbine engine (para 2, 23) comprising: a vane outer shroud for a gas turbine engine, the vane outer shroud comprising: a plurality of vanes coupled to the vane outer shroud (para 2); an outer shroud (Fig 7 or 8; shroud 30); an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane (para 2; Fig 7 or 8; rotor blades 20); and a single undercut groove (groove formed by wall 71 and 100), wherein the single undercut groove is formed radially outward into the vane outer shroud and is located entirely upstream, forward, and adjacent to a leading edge of a blade shroud of each rotor blade (Fig 7 or 8), and wherein the single undercut groove is configured to recirculate generate a local aerodynamic recirculation of air and/or gas radially inward toward the rotor blade, wherein the local aerodynamic recirculation forms a barrier that discourages air and/or gas from leaking through a blade tip of the rotor blade (para 1-7, 25-30; the “vortex” is recirculated flow radially inward 75, 85 toward the rotor blade – see Fig 1; effective flow area E is therefore reduced relative to area A – e.g. flow is discouraged). It would have been obvious to one of ordinary skill in the art at the time of the invention to provide a vane outer shroud for a gas turbine engine, the vane outer shroud comprising: a plurality of vanes coupled to the vane outer shroud; an outer shroud; an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane; and a single undercut groove, wherein the single undercut groove is formed radially outward into the vane outer shroud and is located entirely upstream, forward, and adjacent to a leading edge of a blade shroud of each rotor blade, and wherein the single undercut groove is configured to recirculate generate a local aerodynamic recirculation of air and/or gas radially inward toward the rotor blade, wherein the local aerodynamic recirculation forms a barrier that discourages air and/or gas from leaking through a blade tip of the rotor blade in order to reduce leakage over the blade and improve performance, as taught by John (para 23).
Davis in view of John teaches a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane as discussed above. However, even if Davis in view of John did not teach a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane, Sasada teaches a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane (Fig 5, col 5 ll. 16-30; vanes 2, blades 6, vane outer shroud 1). It would have been obvious to one of ordinary skill in the art at the time of the invention to provide a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane in order to deliver fluid to the turbine, as taught by Sasada. It has been held that combining or simple substitution of prior art elements according to known methods to yield predictable results renders the limitation obvious (see MPEP 2141 (III)). In this case, a plurality of vanes coupled to the vane outer shroud, an area downstream of each vane of the plurality of vanes through which a respective rotor blade of a plurality of rotor blades rotates about an axis relative to each respective vane, yields predictable results (passage of fluid from the vanes to the blades).
Regarding claim 16, 19, John in view of Sasada teaches a depth of the single undercut groove is greater than half of a width of the single undercut groove (John Fig 7 or 8; depth is the radial dimension of the groove, from the bottom of wall 72 to the radially outermost point of the groove; width is the axial dimension – from left to right in the figure, from wall 71 to wall 100; the depth is greater than half of the width).
Regarding claim 20, Davis in view of John and Sasada teaches the single undercut groove is configured to have a shape and wherein the shape is at least one of a semicircular shape, a V shape, or a spiral, hook-shape (John Fig 7 or 8; semicircular shape). It would have been obvious to one of ordinary skill in the art at the time of the invention to make the shape a semicircular shape, as taught by John. It has been held that combining or simple substitution of prior art elements according to known methods to yield predictable results renders the limitation obvious (see MPEP 2141 (III)). In this case, make the groove a semicircular shape yields predictable results (flow recirculation).
Claim(s) 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 11680542 (Davis) in view of US 2011/0085892 (John) and US 4662820 (Sasada) and further in view of US 2022/0186842 (Daniels).
Regarding claim 20, John teaches the groove is configured to have a shape and wherein the shape is at least one of a semicircular shape, a V shape, or a spiral, hook-shape as discussed above. However, even if John was not construed as teaching a semi-circular shape, Daniels teaches a groove in an outer shroud that has a semicircular shape (para 21, 94-95). It would have been obvious to one of ordinary skill in the art at the time of the invention to make the shape a semicircular shape, as taught by Daniels. It has been held that combining or simple substitution of prior art elements according to known methods to yield predictable results renders the limitation obvious (see MPEP 2141 (III)). In this case, making the shape a semicircular shape yields predictable results (reducing leakage).
Response to Arguments
Applicant’s arguments with respect to the claim(s) 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.
With regards to Applicant’s argument that “[t]he consistent use of singular terminology … demonstrates that the inventor contemplated a single undercut groove structure”, “it is an affirmative recitation” and “[t]hese are positive limitations”, Examiner respectfully asserts that the recitation was added to exclude prior art showing multiple grooves. Therefore, the amendment is a negative limitation, excluding multiple grooves. “Any negative limitation or exclusionary proviso must have basis in the original disclosure” and "the mere absence of a positive recitation is not basis for an exclusion" (MPEP 2173.05(i)).
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 ANDREW NGUYEN whose telephone number is (571)270-5063. The examiner can normally be reached 8 am - 4 pm, Monday-Friday.
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/ANDREW H NGUYEN/Primary Examiner, Art Unit 3741
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