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 § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
Claims 1, 3-9 and 12-14 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 13, “at least one fixed stator blades” is unclear whether applicant meant multiple blades, e.g. “at least fixed two blades” or just a “blade”.
Claim 14, “a fixed stator blade” is unclear because claim 14 depends on claim 13 and applicant does not make clear if “a fixed stator blade” has any relationship with that of claim 13. Note that gas turbine engines include many other “fixed stator blade” [e.g. in the compressor, fan, upstream the turbine, etc.] than those downstream of the turbine and thus applicant’s claim is unclear.
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, 3-5, 9, is/are rejected under 35 U.S.C. 103 as being unpatentable over Vassberg et al (2019/0128214) in view of Ostdiek et al (2021/0108597) and in view of optionally1 either Mengle (2010/0257865) of the IDS or Tse (6640537).
PNG
media_image1.png
550
874
media_image1.png
Greyscale
Vassberg et al teach [see mainly Figs. 6A, 6B, and 8, and note that ¶ 0005 teach that different embodiments may be combined] An aeronautical propulsion system configured to receive at least one internal air flow, comprising N stator blades 50 [N =14 from Fig. 8], where N ≥ 2, distributed circumferentially around the central axis, at least one exhaust nozzle 32 through which is ejected the at least one internal air flow, extending around a central axis and being arranged downstream of the stator blades, a reference plane [vertical dashed line in Fig. 6A] positioned at an axial position along the central axis and perpendicular to the central axis, the reference plane defining a trailing edge of the exhaust nozzle, a plurality of chevrons 38 protruding from the reference plane in a direction downstream of the stator blades 50, the plurality of chevrons distributed circumferentially around the central axis, said exhaust nozzle comprising:- N [N=14 from Figs. 6B, 7B] first trailing edge patterns [as illustrated each chevron corresponds to a stator blade] each extending, in an azimuthal direction, over an angular range ΔΘ including one of the N stator blades, the first trailing edge patterns being portions of the trailing edge [e.g. chevron tips when chevron 38 is inline with stator blades 50] or being portions of the trailing edge not having a chevron such that the angular range ΔΘ does not include a chevron [Fig. 6A] such that the angular range ΔΘ does not include a chevron [space between 38], these portions being flat and having the same axial position along the central axis as the reference plane, and - N second trailing edge patterns [e.g. space between chevrons tips, notches] distinct from the first trailing edge patterns and extending, in the azimuthal direction, over an angular range ΔΘ’ including none of the N stator blades [space between 50], the second trailing patterns being portions of the trailing edge comprising at least one chevron [e.g. notch between 38], and being, the number of first trailing edge patterns distinct from one another being comprised between 1 and N [equals N], each angular range ΔΘ including one of the N stator blades 50 being centered on a main axis of the blade, and being such that ΔΘmin < ΔΘ < ΔΘmax, where ΔΘmin = 360/(36*N) [N=14, ΔΘmin = 1⁰] and ΔΘmax=360/(N+1) [N=14, ΔΘmax = 32⁰], ΔΘmin, ΔΘ and ΔΘmax being expressed in degrees – note that since N is 14, the angular spacing between the 14 blades is 360⁰/14= 25.7⁰ and as ΔΘ is the angle including one of the N stator blades, the spacing 25.7⁰ between blades is less than ΔΘmax = 32⁰ which is the maximum allowed angle range for the stator blades to cover. Restated, this range is so broad that at least for the 14 blades situation, the claimed angle range will always be met because the maximum range of ΔΘmax times the number of blades would exceed the perimeter of the entire nozzle. (3) wherein the first trailing edge pattern [flat edge] and/or the second trailing edge pattern [projecting chevrons] are not homothetic geometric patterns [no analogous shape]. (9) wherein S/C < 5 [appears to be in the claimed range in Fig. 9, alternately, it would have been obvious to one of ordinary skill in the art to employ this range, as an obvious matter of using the workable ranges in the art], where S is a distance between the trailing edge of the at least one stator blade 50 at a connection of the stator blade on a casing of the propulsion system and the point of the trailing edge of the exhaust nozzle closest to the stator blade in the direction of the central axis, and C is the chord of the stator blade measured at the connection. Vassberg et al do not teach the aeronautical propulsion system being an unducted double flow turbojet but rather being a ducted turbofan. Ostdiek et al teach the equivalence of the aeronautical propulsion system being a ducted turbojet [Fig. 10] with a unducted turbojet [Figs. 5, 9; see also paragraph 0002]. It would have been obvious to one of ordinary skill in the art to make the aeronautical propulsion system an unducted double flow turbojet, as taught by Ostdiek et al, as an equivalent engine configuration. Ostdiek et al already teach the unducted double flow turbojet [see Figs. 5, 9] and further teach chevrons may be located at either 78 or 79 [see ¶ 0058 and Fig. 9] of the exhaust nozzle. Vassberg et al teach each angular range ΔΘ including one of the N stator blades 50 being centered on a main axis of the blade but do not teach the N stator blades are variable pitch stator blades, the main axis of the blade which is a pitch change axis of the stator blades. Ostdiek et al teach N stator blades 31 are variable pitch stator blades [see actuator 43], the main axis of the blade which is a pitch change axis [vertical dashed line] of the stator blades [see ¶ 0044], each angular range ΔΘ including one of the N stator blades 31 being centered on a main axis of the blade 3 which is the pitch change axis when the stator blades are variable pitch stator blades 30. Ostdiek et al teach making the stator blades as variable pitch stator blades vs fixed are equivalent arrangements or allows one to vary the flow angle from the variable pitch stator blades [see ¶ 0044]. It would have been obvious to one of ordinary skill in the art to employ maintain the spacing of Vassberg’s N stator vanes being between the chevrons and aligned with ΔΘ, with the either the chevrons [78 or 79] of the exhaust of the unducted double flow turbojet, as taught by Ostdiek et al, in order to align the stators between the chevrons of in an engine type typically utilized in the art and regarded by Ostdiek et al as an equivalent engine type. It would further have been obvious to one of ordinary skill in the art to make the N stator blades of Vassberg et al, variable pitch stator blades which has the pitch change axis, in the manner taught by Ostdiek et al, in order to vary the thrust and/or flow angle from the N stators.
Note Vassberg et al illustrate a single chevron per stator blade but teach the number of chevron peaks are integer multiples of the number of stator blades [see paragraph 0021] and so covers claim 4 and (4) wherein the second trailing edge pattern is a portion of the trailing edge comprising at least two chevrons. Vassberg et al do not necessarily teach (5) wherein the at least one second trailing edge pattern comprises at least two chevrons with different amplitudes and/or widths and/or geometries. Mengle teach (5) wherein the at least one second trailing edge pattern comprises at least two chevrons with different amplitudes and/or widths and/or geometries [see Figs. 3, 4, 11C]; (4) wherein the second trailing edge pattern is a portion of the trailing edge comprising at least two chevrons and (3) wherein the first trailing edge pattern and/or the second trailing edge pattern are not homothetic geometric patterns [see Figs. 3, 4, 11C]; and that the differing distributions / geometries allows for tailoring the noise reduction including the direction and different acoustic frequencies [see paragraph 0005, 0007, 0009]. Alternately, Tse teaches (3) wherein the first trailing edge pattern and/or the second trailing edge pattern are not homothetic geometric patterns [see Fig. 1]; and (5) wherein the at least one first trailing edge pattern and/or the at least one second trailing edge pattern comprises at least two chevrons with different amplitudes and/or widths and/or geometries [see Fig. 1]; and (4) wherein the second trailing edge pattern is a portion of the trailing edge comprising at least two chevrons. Tse teaches the irregular trailing edge with different sizes and shapes facilitate the mixing and noise reduction [see col. 6, lines 5-13]. It would have been obvious to one of ordinary skill in the art to employ (3) wherein the first trailing edge pattern and/or the second trailing edge pattern are not homothetic geometric patterns; (4) wherein the second trailing edge pattern is a portion of the trailing edge comprising at least two chevrons; and (5) wherein the at least one second trailing edge pattern comprises at least two chevrons with different amplitudes and/or widths and/or geometries, in the manner taught by Mengle or Tse, as differing distributions / geometries allows for tailoring the noise reduction including the direction and different acoustic frequencies.
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over any of the above prior art and further in view of Ardoin (3,215,172). The above prior art do not teach (8) comprising (i) an upstream portion of the exhaust nozzle and an annular cowling configured to be detachably attached to the upstream portion, a downstream end of the annular cowling comprising the plurality of chevrons. Ardoin teaches (8) comprising (i) an upstream portion 12 of the exhaust nozzle, and an annular cowling 15 configured to be detachably attached 13, 14 to the upstream portion 12, a downstream end of the annular cowling comprising the plurality of chevrons 17. Ardoin teaches this configuration allows the noise suppressor to be
“quickly and easily installed on or detached from existing engines or alternatively may be constructed as an integral part of an engine [lines bridging col. 1-col. 2].”
It would have been obvious to employ (i) an upstream portion of the exhaust nozzle, and an annular cowling configured to be detachably attached to the upstream portion, a downstream end of the annular cowling comprising the plurality of chevrons, in the manner taught by Ardoin, to attach the chevrons to the upstream portion, (i) an upstream portion, and an annular cowling configured to be detachably attached to the upstream portion, a downstream end of the annular cowling comprising the plurality of chevrons, as it facilitates quickly and easily installation or detachment from existing engines, which facilitates repair.
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over any of the above prior art and further in view of Moore et al (2011/0167785). The prior art do not teach (6) the at least one first trailing edge pattern and/or the at least one second trailing edge pattern comprise two chevrons so as to form at least one interval between said at least two chevrons, the at least one interval is filled at least partially with a porous material. Moore et al teach trailing edge pattern comprise two chevrons so as to form at least one interval between said at least two chevrons, the at least one interval is filled at least partially with a porous material 137[Fig. 9-12C]. Moore et al teach the acoustic
“[0079] The primary role of the forward/upstream part of the acoustic lining 137 on the outer wall of the mixer duct shell 134' will be targeting the same sound source(s) that the acoustic lining on the fan duct inner wall 36a', as shown in FIG. 18. Because the annular fan "duct" terminates at completion of the fan-nozzle trailing edge (or Chevrons, if they are used) the acoustic lining 137 on the outer wall of the mixer duct shell 134' can either be unchanged relative to the rest to save costs. Alternatively, the acoustic lining 137 downstream of the fan nozzle exit on the outer surface of the mixer duct shell 134' can be altered to target broadband noise through use of the same bulk absorbing material used on the inner wall of the mixer duct shell 134', and the same face sheet used on the forward part of the outer shell, but with a relatively high level of porosity (25% to 40%). “
Note that the different parts of Fig. 12 refer to acoustic liner and the acoustic lining are present in the context of the chevrons B1 in Fig. 12C, including between adjacent chevrons as the acoustic lining extends to the fan trailing edge/chevrons according to the excerpted text. It would have been obvious to one of ordinary skill in the art to employ porous material / acoustic lining, i.e. at least one first trailing edge pattern and/or the at least one second trailing edge pattern comprise two chevrons so as to form at least one interval between said at least two chevrons, the at least one interval is filled at least partially with a porous material, in the manner taught by Moore et al, to absorb acoustic energy / reduce engine noise.
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over any of the above prior art and further in view of Webster (2013/0017065). The prior art do not teach (7) wherein, the at least one second trailing edge pattern comprise two chevrons so as to form at least one interval between said at least two chevrons, the at least one interval is filled at least partially with a plurality of metal slats. Webster teach (7) wherein, the at least one second trailing edge pattern comprise two chevrons 16, 18 so as to form at least one interval between said at least two chevrons, the at least one interval is filled at least partially with a plurality of metal slats 48, 50 [Fig. 17]. Webster teaches this arrangement facilitates enhancing the mixing and provides a rigid structure to the nozzle. While not specifically mentioning the slats are of metal, the adjacent chevrons 16, 18 are made of alloy, which is by definition a metal, and thus the materials at that location between the chevrons are understood to be metal / metal alloy. It would have been obvious to one of ordinary skill in the art to make the at least one first trailing edge pattern and/or the at least one second trailing edge pattern comprise two chevrons so as to form at least one interval between said at least two chevrons, the at least one interval is filled at least partially with a plurality of metal slats, in the manner taught by Webster, in order to facilitate enhance the mixing and still provide a rigid structure to the nozzle, and further it would have been obvious that making the slats metal, is the typical material used in that location, as evidenced by the adjacent materials being of metal alloy.
Claim(s) 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Vassberg et al (2019/0128214) in view of Ostdiek et al (2021/0108597) and in view of optionally either Mengle (2010/0257865) of the IDS or Tse (6640537), as applied above, and further in view of either Rolt (2016/0010589) or Wright (3632224). Ostdiek et al already teach the unducted double flow turbojet [see Figs. 5, 9] and further teach (13) wherein an outer surface of the exhaust nozzle 78 delimits an external air flow and where chevrons may be located at either 78 or 79 [see ¶ 0058 and Fig. 9]. It would have been obvious to one of ordinary skill in the art to employ the spacing of Vassberg with the unducted double flow turbojet, where an outer surface of the exhaust nozzle delimits an external air flow, in order to align the stators between the chevrons of the prior art in an engine type typically utilized in the art and regarded by Ostdiek et al as an equivalent engine type. Vassberg et al do not teach wherein at least one fixed stator blades being arranged in the internal air flow downstream of a low pressure turbine and upstream of the exhaust nozzle. Rolt teaches wherein at least one fixed stator blades 83 [¶ 0106] being arranged in the internal air flow downstream of a low pressure turbine 22, 78 [¶ 0110] and upstream of the exhaust nozzle to provide structural support. Wright teaches wherein at least one fixed stator blades 36 being arranged in the internal air flow downstream of a low pressure turbine 22 and upstream of the exhaust nozzle 28 in order to straighten the flow to the exhaust nozzle [col. 2, lines 51-58]. It would have been obvious to one of ordinary skill in the art to have at least one fixed stator blades being arranged in the internal air flow downstream of a low pressure turbine and upstream of the exhaust nozzle, as taught by either Rolt or Wright, as the typical practice in the art, and which provides either structural support or flow straightening from the turbine.
Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Vassberg et al (2019/0128214) in view of Ostdiek et al (2021/0108597) and in view of optionally either Mengle (2010/0257865) of the IDS or Tse (6640537), and in view of either Rolt (2016/0010589) or Wright (3632224), as applied above, and further in view of either Larson (4284170) or Hoerst (3648800). Vassberg already teach (14) the trailing edge of the exhaust nozzle comprising the at least one first pattern [no chevron] and the at least one second trailing edge pattern [chevron]. Vassberg broadly teaches the at least one first trailing edge pattern [solid lines] being arranged in such a manner that the angular range ΔΘ over which it extends includes a fixed stator blade 50. As for the at least one first trailing edge pattern being arranged in such a manner that the angular range ΔΘ over which it extends includes a fixed stator blade, note that angular range ΔΘ covers the range that does not include a chevron. Larson teaches that first trailing edge pattern [between chevrons 16] being arranged in such a manner that the angular range ΔΘ between the chevrons is relatively large and irregular and far larger than the circumference of the nozzle covered by the chevrons. Similarly, Hoerst teaches that the at least one first trailing edge pattern [space between chevrons 26 in Figs 3-5] is far larger than the portion of the circumference covered by the chevrons 26 [only 4 chevrons themselves] themselves and being arranged in such a manner that the angular range ΔΘ is relatively large. Note that the number of fixed stators of Wright is relatively large and evenly spaced about the circumference and comparable to the number of rotating turbine blades 32 [see Figs 4, 5]. The angular range ΔΘ over which it extends includes a fixed stator blade, is considered an obvious matter of using the workable ranges in the art, when combined with e.g. the relatively large spacing of ΔΘ known in the art from either Larson or Hoerst. In other words, using more fixed blades which are evenly spaced than chevrons in either Larson or Hoerst, would readily result in at least one angular range ΔΘ between chevrons to include a fixed stator blade. It would have been obvious to one of ordinary skill in the art to employ at least one first trailing edge pattern being arranged in such a manner that the angular range ΔΘ [between chevrons] over which it extends includes a fixed stator blade, as an obvious matter of using relatively large gaps between the chevrons, as taught by either Larson or Hoerst, as a typical arrangement utilized in the art and of using a relatively higher number of fixed blades downstream of the turbine, e.g. than the number of chevrons, as an obvious matter of using the workable ranges in the art.
Response to Arguments
Applicant's arguments filed 5/21/2026 have been fully considered but they are not persuasive.
Applicant’s central argument concerning Vassberg is not persuasive, arguing:
“Vassberg discloses that "the plurality of periodic curves 40 forming the serrated trailing edge 38 on the fan cowl 32 may be generally characterized as chevron shaped." (Vassberg at [0019].) As shown in annotated Fig. 8 of Vassberg reproduced below, the outer guide vanes (OGVs) are aligned with the serrated trailing edge portions 38 formed by periodic curves 40. In particular, the periodic curves 40 protrude from the reference plane (RP) and remain present in the angular regions corresponding to the OGVs. Thus, the OGVs are centered on chevron portions of the trailing edge, as the serrated trailing edge portions 38 protrude from the reference plane, rather than on flat non-chevron portions lying in the reference plane.”
In rebuttal, Vassberg teaches the struts are aligned with the longitudinal lines that separate the chevrons. Since the struts of Fig. 8 have an angled inclination, the downstream end appears it may overlap with a small portion of the chevron. However, when combining with the embodiment of Fig. 6A, 6B, an analogous alignment with the longitudinal lines would clearly be in the space between the chevrons and absent the chevron.
PNG
media_image1.png
550
874
media_image1.png
Greyscale
Furthermore, the teachings of Mengle and Young with respect to claim 1 are now merely additive to that of Figs. 6A, 6B, 8 of Vassberg et al. Note that Young shows the first trailing edge patterns [portions between 10] being portions of the trailing edge not having a chevron, these portions [between 10] being straight and comprised in a same reference plane; and the second trailing edge pattern being chevrons. However, as this teaching is additive, it is no longer(4) applied against claim 1.
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.
Contact Information
Any inquiry concerning this communication or earlier communications from the Examiner should be directed to TED KIM whose telephone number is 571-272-4829. The Examiner can be reached on regular business hours before 5:00 pm, Monday to Thursday and every other Friday.
The fax number for the organization where this application is assigned is 571-273-8300.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Devon Kramer, can be reached at 571-272-7118 Alternate inquiries to Technology Center 3700 can be made via 571-272-3700.
Information regarding the status of an application may be obtained from Patent Center https://www.uspto.gov/patents/apply/patent-center. Should you have questions on Patent Center, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). General inquiries can also be directed to the Inventors Assistance Center whose telephone number is 800-786-9199. Furthermore, a variety of online resources are available at https://www.uspto.gov/patent
/Ted Kim/
Telephone
571-272-4829
Primary Examiner
Fax
571-273-8300
August 3, 2026
1 for claims 3, 5, the teachings of either Mengle (2010/0257865) of the IDS or Tse (6640537) or not optional.
Prosecution Insights