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 § 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, 4, 6-10, 13, 15-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hrach et al (2020/0025149) in view of Gansler et al (2019/0002116) and Muldoon et al (2022/0397064). Hrach et al teaches (1) A method for a hybrid electric propulsion (HEP) system, comprising: receiving a throttle command 606 for a hybrid electric propulsion (HEP) system, wherein the HEP system includes a gas turbine engine 320 and an electric motor 360 or 362 configured to assist the gas turbine engine 320 by rotating a first shaft 330 or 332 of the gas turbine engine; determining a power allocation between the gas turbine engine and the electric motor 360 or 362 for an acceleration period during which a rotational speed of the first shaft 330 or 332 of the gas turbine is accelerated to implement the throttle command 606, wherein the first shaft is part of a low pressure spool of the gas turbine engine or a high pressure spool 332 of the gas turbine engine; and a target clearance 160 between a tip of a rotor blade and a case structure for the acceleration period; and during the acceleration period, implementing the power allocation and operating an active clearance control 160 (ACC) system 614 to establish the target clearance 160; wherein, for a particular throttle command 606, as the amount of electric power available increases, the target clearance 160 decreases [see Fig. 5B, note curve 554 corresponds to electric motor operated clearance and curve 552 is a baseline clearance corresponding to gas turbine only engine operation {and is operable with a battery power of zero}; note 554 decreases from the left axis to TCH relative to curve 552 from the left axis to TCB, compare with applicant’s own Fig. 4, which shows the clearance gap, P3 for 100% battery charge is decreased relative to when the battery charge is zero, P1]. (4) wherein: the electric motor is a first motor-generator 360 or 362 [or vice versa], and the HEP system includes a second motor-generator 362 or 360 [or vice versa] configured to drive rotation of a second shaft. (6) wherein the rotor blade is a blade of a high pressure turbine, and the first shaft 330 or 332 is part of the high pressure spool 332 or the low pressure spool 330. (9, 18) wherein the first shaft 330 is part of the low pressure spool 330. (10) A system for an aircraft, comprising: an active clearance control 160 (ACC) system 614 configured to control a clearance between a tip of a rotating blade and a case structure by controlling thermal growth of the case structure; a hybrid electric propulsion (HEP) system that includes a gas turbine engine 320 and an electric motor configured to assist the gas turbine engine 320 by rotating a first shaft 330 or 332 of the gas turbine engine; one or more batteries [0027] configured to power the electric motor; and a controller configured to: receive a throttle command 606; determine: a power allocation between the gas turbine engine and the electric motor for an acceleration period during which a rotational speed of the first shaft 330 or 332 of the gas turbine is accelerated to implement the throttle command 606, wherein the first shaft is part of a low pressure spool 330 of the gas turbine engine or a high pressure spool 332 of the gas turbine engine; and a target clearance 614 between a tip of a rotor blade and a case structure for the acceleration period; and during the acceleration period, implement the power allocation and operate the ACC system 614 to establish the target clearance 160; wherein for a particular throttle command 606, as the amount of electric power available increases, decrease the target clearance 160 [see Fig. 5B, note curve 554 corresponds to electric motor operated clearance and curve 552 is a baseline clearance corresponding to gas turbine only engine operation {and is operable with a battery power of zero}; note 554 decreases from the left axis to TCH relative to curve 552 from the left axis to TCB, compare with applicant’s own Fig. 4, which shows the clearance gap, P3 for 100% battery charge is decreased relative to when the battery charge is zero, P1]. (13) wherein: the electric motor is a first motor-generator 360 or 362 [or vice versa], and the HEP system includes a second motor-generator 362 or 360 [or vice versa] configured to drive rotation of the second shaft; (15) wherein the rotor blade is a blade of a high pressure turbine, and the first shaft is part of the high pressure spool 332 or the low pressure spool 330. (16) wherein the controller is configured to: implement a first acceleration rate for the first shaft during the acceleration period for a first amount of the available electric power; and implement a second acceleration rate for the first shaft during the acceleration period for a second amount of the available electric power; wherein the first amount of available electric power is greater than the second amount of electric power, and the first acceleration rate is less than the second acceleration rate..
Hrach et al do not teach determining an amount of electric power available to the electric motor based on a charge level of a battery configured to power the electric motor and determining, based on an amount of electric power available to the electric motor 360 or 362: power allocation between the gas turbine engine and the electric motor / controller configured to: receive a throttle command 606; determine, based on an amount of electric power available to the electric motor: a power allocation between the gas turbine engine and the electric motor; nor (10) wherein the controller is configured to determine an amount of electric power available to the electric motor based on a charge level of the one or more batteries; determine, based on the determined an amount of electric power available to the electric motor. Note that the power allocation between the motor and turbine engine are always controlled. Gansler et al teach (1) A method for a hybrid electric propulsion (HEP) system, comprising: receiving a throttle command [0110] for a hybrid electric propulsion (HEP) system, wherein the HEP system includes a gas turbine engine 100 and an electric motor 206 configured to assist the gas turbine engine by rotating a first shaft 210 of the gas turbine engine; determining an amount of electric power available to the electric motor based on a charge level of a battery configured to power the electric motor [e.g. state of charge, ¶ 0101-0106]; determining, based on the determine amount of electric power available to the electric motor: a power allocation between the gas turbine engine and the electric motor for an acceleration period during which a rotational speed of the first shaft 210 of the gas turbine is accelerated to implement the throttle command, wherein the first shaft 210 is part of a low pressure spool of the gas turbine engine or a high pressure spool of the gas turbine engine; and a target clearance 160 between a tip of a rotor blade and a case structure for the acceleration period; and during the acceleration period, implementing the power allocation [note both the electric motor power is controlled and the gas turbine shaft is controlled] and operating an active clearance control 160 (ACC) system to establish the target clearance 160. (10) A system for an aircraft, comprising: an active clearance control 160 (ACC) system configured to control a clearance between a tip of a rotating blade and a case structure by controlling thermal growth of the case structure; a hybrid electric propulsion (HEP) system that includes a gas turbine engine and an electric motor configured to assist the gas turbine engine by rotating a first shaft of the gas turbine engine; one or more batteries [with state of charge, ¶ 0101-0106} configured to power the electric motor; and a controller configured to: receive a throttle command; determine an amount of electric power available to the electric motor based on a charge level of the one or more batteries [e.g. state of charge, ¶ 0101-0106]; determine, based on the determined an amount of electric power available to the electric motor: a power allocation between the gas turbine engine and the electric motor for an acceleration period during which a rotational speed of the first shaft of the gas turbine is accelerated to implement the throttle command, wherein the first shaft is part of a low pressure spool of the gas turbine engine or a high pressure spool of the gas turbine engine; and a target clearance 160 between a tip of a rotor blade and a case structure for the acceleration period; and during the acceleration period, implement the power allocation [note both the electric motor power is controlled and the gas turbine shaft is controlled] and operate the ACC system to establish the target clearance 160. Gansler teaches the state of charge is used to determine the power output [and requisite for the mode of operation, e.g. turbine only or hybrid with the electric motor] and modulating the power output for the electric motor and thus the power allocation between the motor and turbine. It would have been obvious to one of ordinary skill in the art to be determining / determine an amount of electric power available to the electric motor based on a charge level of a battery configured to power the electric motor; determine / determining, based on the determined amount of electric power available to the electric motor: a power allocation between the gas turbine engine and the electric motor, as taught by Gansler et al, in order to control the acceleration of the first shaft and its clearance control by using the state of charge which is used to determine the power output [and requisite for the mode of operation, e.g. turbine only or hybrid with the electric motor] and modulating the power output for the electric motor and thus the power allocation between the motor and turbine. Note that in Hrach, wherein, for a particular throttle command, as the amount of electric power available increases, the target clearance 160 decreases in an analogous manner to applicant’s disclosure [see Fig. 5B, note curve 554 corresponds to electric motor operated clearance and curve 552 is a baseline clearance corresponding to gas turbine only engine operation {and is operable with a battery power of zero}; note 554 decreases from the left axis to TCH relative to curve 552 from the left axis to TCB, compare with applicant’s own Fig. 4, which shows the clearance gap, P3 for 100% battery charge is decreased relative to when the battery charge is zero, P1]. Similarly, wherein, for a particular throttle command, as the amount of electric power available increases, the controller would decrease the target clearance 160 in an analogous manner to applicant’s disclosure [see Fig. 5B, note curve 554 corresponds to electric motor operated clearance and curve 552 is a baseline clearance corresponding to gas turbine only engine operation {and is operable with a battery power of zero}; note 554 decreases from the left axis to TCH relative to curve 552 from the left axis to TCB, compare with applicant’s own Fig. 4, which shows the clearance gap, P3 for 100% battery charge is decreased relative to when the battery charge is zero, P1]. For an alternate treatment of the above limitations of claims 1, 10, Muldoon et al teach (1) wherein, for a particular throttle command, as the amount of electric power available increases, the target clearance decreases; (10) wherein the controller is configured to, for a particular throttle command, as the amount of electric power available increases, decrease the target clearance [i.e. an inverse relationship]. In ¶ 0072, Muldoon specifically teaching when the amount of electric power available decreases, the target clearance increases, which is the same [inverse] relationship as that claimed (available power increases, target clearance decreases and vice versa). It would have been obvious to one of ordinary skill in the art to employ (2) for a particular throttle command, as the amount of electric power available increases, the target clearance decreases, as taught by Muldoon, as these variables are inversely related and as the typical way to manage the target clearance based on the amount of the amount of electric power available.
Hrach et al do not teach (8, 17) wherein the rotor blade is a blade of a low pressure turbine 346 of the gas turbine engine. Gansler et al teach (8, 17) wherein the rotor blade [for active clearance control] is a blade of a low pressure turbine of the gas turbine engine. [¶ 0103 teaches rotor blade may be both high pressure turbine and low pressure turbine clearance control]. It would have been obvious to one of ordinary skill in the art to make (8, 17) the rotor blade a blade of a low pressure turbine of the gas turbine engine, as taught by Gansler et al, as an equivalent rotor blade for the active clearance control. Hrach et al would further [see Fig. 5C] teach (7) implementing a first acceleration rate 564 for the first shaft [with power assist from electrical motors, ¶ 0031-0033, acceleration is the slope of the curve 564], during the acceleration period for a first amount of the available electric power; and implementing a second acceleration rate 562 for the first shaft during the acceleration period for a second amount of the available electric power [second acceleration rate 562 – applying power assist from electrical motors, ¶ 0031-0033, acceleration is the slope of the curve 562, baseline performance is the same as an empty battery charge as it does not require any battery charge]; wherein the first amount of the available electric power [during hybrid power assist from electrical motors] is greater than the second amount of the available electric power [baseline performance is the same as an empty battery charge as it does not require any battery charge], and the first acceleration rate 564 is less than the second acceleration rate 562; (16) wherein the controller is configured to: implement a first acceleration rate 564 for the first shaft during the acceleration period for a first amount of the available electric power [hybrid power mode]; and implement a second acceleration rate 562 for the first shaft during the acceleration period for a second amount of the available electric power [baseline performance is the same as an empty battery charge as it does not require any battery charge]; wherein the first amount of available electric power [during hybrid power assist from electrical motors] is greater than the second amount of electric power [baseline performance is the same as an empty battery charge as it does not require any battery charge], the first acceleration rate 564 is less than the second acceleration rate 562. Note that the curves 564 and 562 of Hrach et al’s Fig. 5C are analogous to applicant’s curves in applicant’s Fig. 4 in that the no battery charge battery condition of applicant’s is analogous to the baseline condition 562 of Hrach et al. Hrach et al already teach (4, 20) wherein: the electric motor is a first motor-generator 360 or 362 [or vice versa], and the HEP system includes a second motor-generator 362 or 360 [or vice versa] configured to drive rotation of a second shaft; and (13) wherein: the electric motor is a first motor-generator 360 or 362 [or vice versa], and the HEP system includes a second motor-generator 362 or 360 [or vice versa] configured to drive rotation of the second shaft. Hrach et al do not teach determining the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator / the controller is configured to determine the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator.
Muldoon et al teach wherein: the electric motor is a first motor-generator 212b / 213b, and the HEP system includes a second motor-generator 212a / 213a configured to drive rotation of a second shaft [bottom of ¶ 0040 teaches the motor and generator functions may be combined into a single unit for each e.g. motor]; and the method further comprises determining / the controller is configured to determine the amount of electric power available to the first motor-generator 212b further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator [¶ 0042 teaches the excess capacity of the second motor-generator 212a is delivered to the first motor – generator 212b and ¶ 0072 teaches the controller 256 operates based on the available power from the motor(s) / power source / batteries]. It would have been obvious to one of ordinary skill in the art to be determining the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator / the controller is configured to determine the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator, as taught by Muldoon et al, in order to facilitate controlling the electric power to the first motor-generator, based on the excess capacity and to effectively manage the electrical power needs for the engine and electric motors.
Claim(s) 1, 4, 6-10, 13, 15-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Gansler et al (2019/0002116) in view of Muldoon et al (2022/0397064). Gansler et al teach (1) A method for a hybrid electric propulsion (HEP) system, comprising: receiving a throttle command [0110] for a hybrid electric propulsion (HEP) system, wherein the HEP system includes a gas turbine engine 100 and an electric motor 206 configured to assist the gas turbine engine by rotating a first shaft 210 of the gas turbine engine; determining an amount of electric power available to the electric motor based on a charge level of a battery configured to power the electric motor [e.g. state of charge, ¶ 0101-0106]; determining, based on the determine amount of electric power available to the electric motor: a power allocation between the gas turbine engine and the electric motor for an acceleration period during which a rotational speed of the first shaft 210 of the gas turbine is accelerated to implement the throttle command, wherein the first shaft 210 is part of a low pressure spool of the gas turbine engine or a high pressure spool of the gas turbine engine; and a target clearance 160 between a tip of a rotor blade and a case structure for the acceleration period; and during the acceleration period, implementing the power allocation [note both the electric motor power is controlled and the gas turbine shaft is controlled] and operating an active clearance control 160 (ACC) system to establish the target clearance 160. (6) wherein the rotor blade is a blade of a high pressure turbine 116 [¶ 0103 teaches rotor blade may be both high pressure turbine and low pressure turbine clearance control], and the first shaft is part of the high pressure spool or the low pressure spool 218. (7) implementing a first acceleration rate for the first shaft, during the acceleration period for a first amount of the available electric power; and implementing a second acceleration rate for the first shaft during the acceleration period for a second amount of the available electric power; wherein the first amount of the available electric power is greater than the second amount of the available electric power, and the first acceleration rate is less than the second acceleration rate. (8) wherein the rotor blade is a blade of a low pressure turbine of the gas turbine engine. [¶ 0103 teaches rotor blade may be both high pressure turbine and low pressure turbine clearance control]. (9) wherein the first shaft 210 is part of the low pressure spool [¶ 0103]. (17) wherein the rotor blade is a blade of a low pressure turbine of the gas turbine engine [¶ 0103 teaches rotor blade may be both high pressure turbine and low pressure turbine clearance control]. (18) wherein the first shaft 210 is part of the low pressure spool. (10) A system for an aircraft, comprising: an active clearance control 160 (ACC) system configured to control a clearance between a tip of a rotating blade and a case structure by controlling thermal growth of the case structure; a hybrid electric propulsion (HEP) system that includes a gas turbine engine and an electric motor configured to assist the gas turbine engine by rotating a first shaft of the gas turbine engine; one or more batteries [with state of charge, ¶ 0101-0106} configured to power the electric motor; and a controller configured to: receive a throttle command; determine an amount of electric power available to the electric motor based on a charge level of the one or more batteries [e.g. state of charge, ¶ 0101-0106]; determine, based on the determined an amount of electric power available to the electric motor: a power allocation between the gas turbine engine and the electric motor for an acceleration period during which a rotational speed of the first shaft of the gas turbine is accelerated to implement the throttle command, wherein the first shaft is part of a low pressure spool of the gas turbine engine or a high pressure spool of the gas turbine engine; and a target clearance 160 between a tip of a rotor blade and a case structure for the acceleration period; and during the acceleration period, implement the power allocation [note both the electric motor power is controlled and the gas turbine shaft is controlled] and operate the ACC system to establish the target clearance 160. (15) wherein the rotor blade is a blade of a high pressure turbine 116, and the first shaft is part of the high pressure spool or the low pressure spool. (16) wherein the controller is configured to: implement a first acceleration rate for the first shaft during the acceleration period for a first amount of the available electric power; and implement a second acceleration rate for the first shaft during the acceleration period for a second amount of the available electric power; wherein the first amount of available electric power is greater than the second amount of electric power, and the first acceleration rate is less than the second acceleration rate..
Gansler et al do not teach (1) wherein, for a particular throttle command, as the amount of electric power available increases, the target clearance decreases; (10) wherein the controller is configured to, for a particular throttle command, as the amount of electric power available increases, decrease the target clearance. Muldoon et al teach (1) wherein, for a particular throttle command, as the amount of electric power available increases, the target clearance decreases; (10) wherein the controller is configured to, for a particular throttle command, as the amount of electric power available increases, decrease the target clearance [i.e. an inverse relationship]. In ¶ 0072, Muldoon specifically teaching when the amount of electric power available decreases, the target clearance increases, which is the same [inverse] relationship as that claimed (available power increases, target clearance decreases and vice versa). It would have been obvious to one of ordinary skill in the art to employ (2) for a particular throttle command, as the amount of electric power available increases, the target clearance decreases, as taught by Muldoon, as these variables are inversely related and as the typical way to manage the target clearance based on the amount of the amount of electric power available. wherein: the electric motor is a first motor-generator, and the HEP system includes a second motor- generator configured to drive rotation of a second shaft; and the method further comprises determining the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor- generator due to excess capacity of the second motor-generator
Gansler et al teach (4) wherein: the electric motor is a first motor-generator, and the HEP system includes a second motor-generator configured to drive rotation of a second shaft [see ¶ 0070 which teaches each of the HP and LP shafts have their own motor-generator per shaft]; (13) wherein: the electric motor is a first motor-generator, and the HEP system includes a second motor- generator configured to drive rotation of the second shaft [see ¶ 0070 which teaches each of the HP and LP shafts have their own motor-generator per shaft]. Gansler et al do not teach the method further comprises determining the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor- generator due to excess capacity of the second motor-generator; and the controller is configured to determine the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator. Muldoon et al teach wherein: the electric motor is a first motor-generator 212b / 213b, and the HEP system includes a second motor-generator 212a / 213a configured to drive rotation of a second shaft [bottom of ¶ 0040 teaches the motor and generator functions may be combined into a single unit for each e.g. motor]; and the method further comprises determining / the controller is configured to determine the amount of electric power available to the first motor-generator 212b further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator [¶ 0042 teaches the excess capacity of the second motor-generator 212a is delivered to the first motor – generator 212b and ¶ 0072 teaches the controller 256 operates based on the available power from the motor(s) / power source / batteries]. It would have been obvious to one of ordinary skill in the art to be determining the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator / the controller is configured to determine the amount of electric power available to the first motor-generator further based on an amount of power available from the second motor-generator due to excess capacity of the second motor-generator, as taught by Muldoon et al, in order to facilitate controlling the electric power to the first motor-generator, based on the excess capacity and to effectively manage the electrical power needs for the engine and electric motors.
Response to Arguments
Applicant's arguments filed 3/16/2026 have been fully considered but they are not persuasive.
Applicant’s arguments for Hrach et al combination center around claims 2 and 11 which have been incorporated into the independent claims. However, applicant did not argue the rejection of claims 2 and 11 which had combinations with the Muldoon et al (2022/0397064) reference. Accordingly, Applicant's arguments fail to comply with 37 CFR 1.111(b) because they amount to a general allegation that the claims define a patentable invention without specifically pointing out how the language of the claims patentably distinguishes them from the references. For the Hrach reference, applicant also alleges there is no explanation for how that the target clearance relates to the determined electric power available. However, it is because it is clear from the reference and other claims, e.g. claim 7 already teach the analysis with the acceleration for the available electric power and the target clearance is clearly shown in Fig. 5B. Nevertheless, to address applicant’s concerns, in Hrach, wherein, for a particular throttle command, as the amount of electric power available increases, the target clearance 160 decreases / decreasing the target clearance 160 in an analogous manner to applicant’s disclosure. See Fig. 5B of Hrach, note curve 554 corresponds to electric motor operated clearance and curve 552 is a baseline clearance corresponding to gas turbine only engine operation {and operable with a battery power of zero since this is engine only operation}; note 554 decreases from the left axis to TCH relative to curve 552 from the left axis to TCB, compare with applicant’s own Fig. 4, which shows the clearance gap, P3 for 100% battery charge is decreased relative to when the battery charge is zero, P1. As the target clearances are shown in Fig. 5B, with or without electric power, i.e. gas turbine only vs electric motor / hybrid mode, it is clear that Hrach operates in an analogous manner to applicant’s device and while it requires the determining of the amount of electric power available, this is taught by Gansler, e.g. state of charge, to meet the claimed limitations. Gansler teaches using the state of charge is well known and needed information to operate the electric motor in hybrid operation vs gas turbine engine only.
For the Gansler reference, applicant cites an excerpt from ¶ 0103 but alleges:
“Thus, Gansler teaches that the clearance is increased when its electric machine uses power. However, there is no disclosure that a target clearance is determined "based on the determined amount of electric power available to the electric motor" where the amount of electric power available is determined "based on a charge level of a battery configured to power the electric motor."
In rebuttal, ¶ 0101 and 0106 specifically teach the " a charge level of a battery configured to power the electric motor" is used by the controller to control the electric motor and the mode of operation [gas turbine only or hybrid with motor] is clearly dependent on the whether the battery charge is available to operate the electric motor. If electric power is not available, the turbomachine (gas turbine) only clearance control system must be used (i.e. no battery charge). When the electric battery charge is available, then the hybrid clearance is used. Applicant’s citation from a small portion of ¶ 0103 is insufficient since, applicant ignores the rest of the citations of ¶ 0101-0106 [excerpted below]. Note that ¶ 0102 teaches that the target clearances are larger for gas turbine only operation and smaller (tighter/ decreased / decreasing) for the hybrid operation with the electric motor. Accordingly, applicant’s arguments fail to persuade.
[0101] However, in other exemplary aspects, the method 400 may modulate an amount of electrical power provided to the electric machine at (415) based on any other suitable parameters. For example, in other exemplary aspects, as is depicted in phantom in FIG. 8, the method 400 may further include at (422) receiving, by the one or more computing devices, data indicative of a state of charge of the electric energy storage unit. Whit such an exemplary aspect, modulating, by the one or more computing devices, the amount of electrical power provided to the electric machine at (415) may further include, as is depicted in phantom, at (423) modulating, by the one or more computing devices, an amount of electrical power provided to the electric machine based at least in part on the received data indicative of the state of charge of the electric energy storage unit. For example, the method 400 may reduce an amount of electrical power provided to the electric machine when, for example, the charge level of the electric energy storage unit falls below a certain threshold, or approaches a certain threshold.
[0102] Referring back to FIG. 7, as stated, the method 400 may generally be operable to provide a substantially immediate acceleration response once the command to accelerate the turbomachine while operating the turbomachine in the steady-state flight operating condition is received at (410). Accordingly, such may allow for the turbomachine to operate more efficiently at the steady-state flight operating condition. More particularly, for the exemplary aspect of FIG. 7, the turbomachine further includes an active clearance control system. The active clearance control system may modify clearances between one or more turbine rotor blades and an outer flowpath liner within a turbine section of the turbomachine during operation of the turbomachine. Typically, when operating at a steady-state flight operation condition, the clearances are maintained larger than would otherwise be desirable from an efficiency standpoint in order to allow for a relatively quick acceleration of the turbomachine if desired. For example, as will be appreciated, an acceleration of the turbomachine from a steady-state operating condition increases a rotational speed of the turbine rotor blades, and also increases a temperature to which the turbine rotor blades and other components are exposed, resulting in an expansion of the turbine rotor blades and certain other components. The relatively large clearances are maintained to accommodate such expansion. However, given that the hybrid electric propulsion system of the present disclosure, and more specifically, the electric machine coupled to the turbomachine, may provide the substantially immediate acceleration response desired, the active clearance control system may be operated to maintain relatively tight clearances between the turbine rotor blades and, e.g., an outer flowpath liner within the turbine section. For example, for the exemplary aspect of the method 400 depicted, the active clearance control system may maintain desired relatively tight clearances, and in response to receiving a command to accelerate the turbomachine (e.g., at (410)), provide the immediate power response desired through the electric machine, giving the active clearance control system time to increase the clearances (i.e., “loosen-up”) enough to allow the turbomachine to accelerate through combustion.
[0103] Accordingly, for the exemplary aspect of the method 400 depicted, the method 400 further includes at (424) increasing, by the one or more computing devices, one or more clearances within the turbomachine using an active clearance control system in response to the received command to accelerate the turbomachine at (410). The one or more clearances may be turbine rotor blades clearances within, e.g., a high pressure turbine (and/or low pressure turbine) of the turbomachine. Specifically, for the embodiment exemplary aspect depicted, increasing, by the one or more computing devices, one or more clearances within the turbomachine using the active clearance control system at (424) includes at (426) increasing, by the one or more computing devices, one or more clearances within the turbomachine using the active clearance control system substantially simultaneously with providing, by the one or more computing devices, electrical power to the electric machine at (414). Furthermore, with such an exemplary aspect, increasing, by the one or more computing devices, one or more clearances within the turbomachine using the active clearance control system at (424) additionally includes at (428) maintaining, by the one or more computing devices, a fuel flow to a combustion section of the turbomachine substantially constant for an initial time period. Notably, as used herein, the term “substantially constant” may refer to less than a five percent variance from an initial value. For example, in at least certain exemplary aspects, maintaining, by the one or more computing devices, a fuel flow to a combustion section of the turbomachine substantially constant for the initial time period at (428) may accordingly include maintaining a rotational speed of a high pressure system of the turbomachine substantially constant for the initial time period and/or maintaining a temperature within a specific section of the turbomachine (e.g., an exhaust gas temperature) substantially constant for the initial time period.
[0104] The initial time period may be an amount of time sufficient for the active clearance control system to loosen up enough to allow the high pressure system of the turbomachine to accelerate. For example, in certain exemplary aspects, the initial time period may be at least about two seconds, such as at least about five seconds, such as up to about ten seconds, such as up to about five minutes.
[0105] Furthermore, referring now also briefly to FIG. 9, providing another flowchart of an exemplary aspect of the method 400, the method 400 further includes at (430) terminating, by the one or more computing devices, the provision electrical power provided to the electric machine at (414) to add power to the turbomachine, the propulsor, or both in response to received command to accelerate the turbomachine. More specifically, for the exemplary aspect depicted, terminating, by the one or more computing devices, the provision of electrical power provided to the electric machine at (430) includes at (432) terminating, by the one or more computing devices, the provision of electrical power provided to the electric machine at (414) based at least in part on the received data indicative of the operational parameter of the turbomachine at (420). For example, the method 400 may determine the turbomachine is rotating at a desired speed, or operating a desired power level, and terminate the provision of electrical power to the electric machine based on such a determination.
[0106] Alternatively, however, in other exemplary aspects, the method 400 may terminate provision electrical power to the electric machine based on any other suitable determination. For example, in other exemplary aspects, terminating, by the one or more computing devices, the provision of electrical power provided to the electric machine at (430) may include, as is depicted in phantom, at (434) terminating, by the one or more computing device, the provision electrical power provided to the electric machine at (414) based at least in part on the received data indicative of the state of charge the electric energy storage unit at (422). For example, the method 400 may determine a charge level of the electric energy storage unit is below a predetermined threshold, or approaching a predetermined threshold, and terminate the provision electrical power to the electric machine based on such a determination.
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
May 13, 2026
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