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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 11/11/2025 has been entered.
Response to Amendment
The amendment submitted 11/11/2025 has been entered. Claims 1-2, 4-12, and 14-20 remain pending. Claims 3 and 13 have been cancelled.
Response to Arguments
Applicant's arguments filed 11/11/2025 have been fully considered but they are not persuasive. The amendments to the claims have changed the scope of the claims necessitating modified grounds of rejection. Please see modified grounds of rejection below.
The Applicant argues the prior art does not teach wherein “the seal element extends axially across the sensor body radially inboard of the sensor body” as in “Hagi and Buyle, the alleged sensors are not covered by the seal elements”. The Examiner respectfully disagrees. Buyle is explicit that the seal element (“layer of abradable material”, Par 0010) covers the sensor.
Claim Rejections - 35 USC § 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 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, 4-12, and 14- 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 6152685 to Hagi in view of US 20130309063 to Buyle in further view of US 6903541 to Ziegner.
(a) Regarding claim 1:
Hagi discloses a stator assembly of a gas turbine engine (see title), comprising:
a stator including at least:
a stator vane (stationary blade 21, Figs 1/3); and a stator inner platform (inner shroud 23, Figs 1/3) located radially inboard of the stator vane (Figs 1/3);
a stator inner airseal (seal ring retaining ring 24, seal ring 25, Figs 1/3) disposed radially inboard of the stator inner platform (Figs 1/3),
the stator inner airseal configured to define a seal arrangement with two or more knife edges (knife edges of rotor discs 33a/33b interfacing with seal ring 25, Fig 3; see annotated Fig 3 below) of a radially adjacent rotating component (rotor discs 33a/33b); and
a sensor (clearance measuring sensor 14, Fig 1) disposed at the stator inner airseal (Fig 1),
the sensor including a sensor body configured to be positioned axially between axially adjacent knife edges of the two or more knife edges (sensor reasonably disclosed in Fig 1 as being axially located between rotor discs 33a/33b from which the knife edges extend; Figs 1/3) and configured to detect a radial distance from the sensor to the radially adjacent rotating component (Col 3 Lns 66-67), and
wherein the stator inner airseal includes a seal carrier (seal ring 25, Fig 3) and a seal element (structure below and attached to seal ring 25 which interfaces with the knife edges and radially inward rotating surfaces, Figs 1/3) installed into the seal carrier radially inboard of the seal carrier (Figs 1/3).
wherein the sensor body is disposed in a trench (recess into which clearance measuring sensor 14 is located, Fig 1) formed in the stator inner airseal (Fig 1).
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(ii) Hagi does not disclose:
wherein the sensor body is disposed radially between the seal element and the seal carrier such that the seal element extends axially across the sensor body radially inboard of the sensor body between the sensor body and the rotating component; nor
wherein the sensor body is flexible and conformal to a trench shape of the trench.
(iii) Buyle is also in the field of gas turbine engines (see title) and teaches a sensor body (sensors 64, Fig 3) and a seal element (abradable material 70, Fig 3) attached to a radially inner surface of a seal carrier (casing 66, Fig 3), wherein the sensor body is disposed radially between the seal element and the seal carrier such that the seal element extends axially across the sensor body radially inboard of the sensor body (Fig 3, Par 0010) between the sensor body and a rotating component (blades 18, Fig 3).
(iv) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the seal element as disclosed by Hagi to be the seal element as taught by Buyle for the purpose of protecting the sensors from becoming clogged or from moisture (Par 0011), reducing the clearance between the tips of the blades and a casing (Par 0026), and improving the measurement of the clearance at the tips of the blades (Par 0035).
(v) Ziegner is also in the field of sensors (see title) and teaches a sensor (20, Figs 2/7) having a sensor body that is flexible (see abstract) and conformal to a trench shape of a trench (“flexible format, allowing them to be conformed … or to be insert-injection molded into products featuring non-flat or compound surfaces”, Col 5 Lns 33-36).
(vi) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the sensor body as disclosed by Hagi to be flexible and conformal as taught by Ziegner for the purpose of allowing the sensor to conform to non-flat surfaces or to be insert-injection molded into products featuring non-flat or compound surfaces, as well as allowing for the sensor to be manufactured by means of continuous, low cost processing techniques (Col 5 Lns 33-41).
(b) Regarding claim 2:
(i) Hagi as modified by Buyle as further modified by Ziegner teaches the stator assembly of claim 1.
(ii) Hagi further discloses wherein the sensor body is sized and positioned such that the sensor body is configured to be positioned axially between the knife edges (Figs 1/3).
(iii) The limitation “positioned axially between the knife edges during all anticipated operating conditions of the gas turbine engine” is merely functional language and the sensor body of the prior art is capable of being positioned axially between the knife edges during all anticipated operating conditions of the gas turbine engine”.
(c) Regarding claims 4 and 14:
(i) Hagi as modified by Buyle as further modified by Ziegner teaches the stator assembly of claim 1 and the gas turbine engine of claim 11.
(ii) Buyle further teaches wherein the sensor is a capacitance sensor.
(d) Regarding claims 5 and 15:
(i) Hagi as modified by Buyle as further modified by Ziegner teaches the stator assembly of claim 1 and the gas turbine engine of claim 11.
(ii) Buyle further teaches wherein the sensor body has a radial thickness in the range of .005” to .020” (0.4mm, which is about 0.0157”, Par 0033).
(e) Regarding claims 6-7 and 16-17:
(i) Hagi as modified by Buyle as further modified by Ziegner teaches the stator assembly of claim 1 and the gas turbine engine of claim 11.
(ii) Hagi further discloses:
wherein the sensor further includes a signal lead (unlabeled dashed line extending between sensor 14 and control unit 10, Fig 1) extending from the sensor body to outside of the stator assembly (Fig 1);
wherein the signal lead extends through an inner platform opening (passes through inner shroud 23 so an opening must exist, Fig 1) in the stator inner platform (Fig 1);
(f) Regarding claims 8-9 and 18-19:
(i) Hagi as modified by Buyle as further modified by Ziegner teaches the stator assembly of claim 6 and the gas turbine engine of claim 16.
(ii) Buyle further teaches:
wherein the signal lead (cable 68, Fig 3) extends along a stator vane surface (of Hagi as modified by Buyle) of the stator assembly (extends along inside surface of casing 66, Fig 3); and
wherein the signal lead is secured to the stator vane surface via an adhesive (“fine layer of abradable material”, Fig 3, Par 0032).
(g) Regarding claims 10 and 20:
(i) Hagi as modified by Buyle as further modified by Ziegner teaches the stator assembly of claim 1 and the gas turbine engine of claim 16.
(ii) Hagi further discloses wherein:
the stator further includes a stator outer platform (outer shroud 22, Figs 1/3) disposed radially outboard of the stator vane (Figs 1/3); and
the signal lead extends through an outer platform opening in the stator outer platform (Fig 1).
(h) Regarding claim 11:
(i) Hagi discloses a gas turbine engine (see title) comprising:
a rotor (rotor discs 33a/33b, Figs 1/3) configured to rotate about an engine central longitudinal axis (“rotor axis”, Col 1 Lns 26-28),
the rotor including:
a rotor body (body of rotor discs 33a/33b, Figs 1/3); and
two or more knife edges (knife edges of rotor discs 33a/33b interfacing with seal ring 25, Fig 3; see annotated Fig 3 below) extending radially outwardly from the rotor body (Fig 3); and
a stator assembly disposed radially outboard of the rotor, the stator assembly including:
a stator including at least: a stator vane (stationary blade 21, Figs 1/3); and
a stator inner platform (inner shroud 23, Figs 1/3) located radially inboard of the stator vane (Figs 1/3);
a stator inner airseal (seal ring retaining ring 24, seal ring 25, Figs 1/3) disposed radially inboard of the stator inner platform (Figs 1/3),
the stator inner airseal defining a seal arrangement with the two or more knife edges (with seal ring 25, Fig 3; Col 1 Lns 19-20); and
a sensor (clearance measuring sensor 14, Fig 1) disposed at the stator inner airseal (Fig 1),
the sensor including a sensor body positioned axially between axially adjacent knife edges of the two or more knife edges (sensor reasonably disclosed in Fig 1 as being axially located between rotor discs 33a/33b from which the knife edges extend;) and configured to detect a radial distance from the sensor to the rotor body (Col 3 Lns 66-67),
wherein the stator inner airseal includes a seal carrier (seal ring 25, Fig 3) and a seal element (structure below and attached to seal ring 25 which interfaces with the knife edges and radially inward rotating surfaces, Figs 1/3) installed into the seal carrier radially inboard of the seal carrier (Figs 1/3),
wherein the sensor body is disposed in a trench (recess into which clearance measuring sensor 14 is located, Fig 1) formed in the stator inner airseal (Fig 1).
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(ii) Hagi does not disclose:
wherein the sensor body is disposed radially between the seal element and the seal carrier such that the seal element extends axially across the sensor body radially inboard of the sensor body between the sensor body and the rotating component; nor
wherein the sensor body is flexible and conformal to a trench shape of the trench.
(iii) Buyle is also in the field of gas turbine engines (see title) and teaches a sensor body (sensors 64, Fig 3) and a seal element (abradable material 70, Fig 3) attached to a radially inner surface of a seal carrier (casing 66, Fig 3), wherein the sensor body is disposed radially between the seal element and the seal carrier such that the seal element extends axially across the sensor body radially inboard of the sensor body (Fig 3, Par 0010) between the sensor body and a rotating component (blades 18, Fig 3).
(iv) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the seal element as disclosed by Hagi to be the seal element as taught by Buyle for the purpose of protecting the sensors from becoming clogged or from moisture (Par 0011), reducing the clearance between the tips of the blades and a casing (Par 0026), and improving the measurement of the clearance at the tips of the blades (Par 0035).
(v) Ziegner is also in the field of sensors (see title) and teaches a sensor (20, Figs 2/7) having a sensor body that is flexible (see abstract) and conformal to a trench shape of a trench (“flexible format, allowing them to be conformed … or to be insert-injection molded into products featuring non-flat or compound surfaces”, Col 5 Lns 33-36).
(vi) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the sensor body as disclosed by Hagi to be flexible and conformal as taught by Ziegner for the purpose of allowing the sensor to conform to non-flat surfaces or to be insert-injection molded into products featuring non-flat or compound surfaces, as well as allowing for the sensor to be manufactured by means of continuous, low cost processing techniques (Col 5 Lns 33-41).
(i) Regarding claim 12:
(i) Hagi as modified by Buyle as further modified by Ziegner teaches the gas turbine engine of claim 11.
(ii) Hagi further discloses wherein the sensor body is sized and positioned such that the sensor body is configured to be positioned axially between the knife edges (Figs 1/3).
(ii) The limitation “positioned axially between the knife edges during all anticipated operating conditions of the gas turbine engine” is merely functional language and the sensor body of the prior art is capable of being positioned axially between the knife edges during all anticipated operating conditions of the gas turbine engine”.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Justin A Pruitt whose telephone number is (571)272-8383. The examiner can normally be reached T-F 8:30am - 6:30pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Nathaniel Wiehe can be reached at (571) 272-8648. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JUSTIN A PRUITT/Examiner, Art Unit 3745
/NATHANIEL E WIEHE/Supervisory Patent Examiner, Art Unit 3745