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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 10/14/2025 has been entered.
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 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.
Claims 1, 2, 7-10, and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Many (1704753) in view of Woodward (4118997).
Regarding claim 1, Many discloses a propulsion system for an aircraft (fig 1), comprising: a first propulsor rotor (E, fig 1) rotatably driven by a rotating structure (C, fig 3) during a first mode and a second mode (page 1, lines 85-100), the first mode being a horizontal flight mode and the second mode being a vertical flight mode and/or a hover flight mode (page 1, lines 1-15), the first propulsor rotor comprising a plurality of variable pitch blades (page 1, line 107 to page 2, line 18), the plurality of variable pitchy blades comprising a first blade configured to pivot between a thrust position and an idle position (thrust position for horizontal flight and idle position in the neutral position), the first blade in the thrust position during the first mode, and the first blade in the idle position during the second mode; and a second propulsor (F, fig 1) rotatably driven during the second mode, wherein a geartrain (S, H, K, fig 3) couples the rotating structure to the first propulsor rotor during the first mode and the second mode, and the geartrain couples the rotating structure to the second propulsor during the second mode; wherein the second propulsor rotor comprises an open rotor (fig 1); and wherein the first propulsor rotor is configured to generate thrust during the first mode, and generate substantially no thrust during the second mode.
Many does not disclose a gas turbine engine core including a compressor section, a combustor section, a turbine section, and a rotating structure comprising a turbine rotor with the turbine section, and the first propulsor rotor comprising a ducted rotor.
Woodward teaches a propulsion system for an aircraft (1, fig 1), comprising: a gas turbine engine core including a compressor section (12, 13, fig 2), a combustor section (14, fig 2), a turbine section (15, 16, fig 2) and a rotating structure (6, fig 1), the rotating structure comprising a turbine rotor (the shaft connects all the main rotatable core components) within the turbine section; a first propulsor rotor (5, fig 2) rotatably driven by the rotating structure during a first mode and a second mode, the first propulsor rotor comprising a plurality of variable pitch blades (24, fig 2), the plurality of variable pitch blades comprising a first blade (5, fig 2) configured to pivot between a thrust position and an idle position, the first blade in the thrust position during the first mode, and the first blade in the idle position during the second mode (due to the language configured to be, the blade must merely be capable of doing so, which it is), and the first propulsor rotor comprising a ducted rotor (19, fig 2); and a second propulsor rotor (3, fig 1) rotatably driven by the rotating structure during the second mode; wherein a geartrain (25, 40, 42, 48, 50, fig 1) couples the rotating structure to the first propulsor rotor during the first mode and the second mode (the reduction gearbox 25 constantly connects the ducted fan 5 to the engine shaft 6), and the geartrain couples the rotating structure to the second propulsor rotor during the second mode (via 7, 9, 10, 11, fig 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have a ducted gas turbine engine with a modern geartrain to drive the horizontal propulsors of Many based on the teachings of Woodward. One of ordinary skill in the art would recognize that gas turbine engines have a much higher power density than older class engines, and thus would be the better choice for an aircraft.
Regarding claim 2, Many discloses a transmission (k, fig 3) configured to decouple the second propulsor rotor from the rotating structure during the first mode; and couple the second propulsor rotor to the rotating structure during the second mode (page 1, lines 70-85).
Regarding claim 7, Many discloses wherein the first propulsor rotor is configured to generate at least twenty times more thrust during the first mode than during the second mode (due to the language configured to generate, the engine must merely be capable of performing the claimed function, since the angle of the fan can be varied, the engine can be dropped down to zero thrust when the pitch angle is turned to 90 degrees vs the 5 to 10 thousand of the engines at full thrust (page 1, line 107 to page 2, line 18)).
Regarding claim 8, Many discloses wherein the first propulsor rotor is configured to generate thrust during the first mode; and generate substantially no thrust during the second mode (due to the language configured to generate, the engine must merely be capable of performing the claimed function, since the angle of the fan can be varied, the engine can be dropped down to zero thrust when the pitch angle is turned to 90 degrees vs the 5 to 10 thousand of the engines at full thrust (page 1, line 107 to page 2, line 18)).
Regarding claim 9, Many discloses wherein the first propulsor rotor is configured to generate horizontal thrust during the first mode; and the second propulsor rotor is configured to generate vertical lift during the second mode (page 1, lines 19-41).
Regarding claim 10, Many discloses wherein the first propulsor rotor is rotatable about a first axis; and the second propulsor rotor is rotatable about a second axis that is angularly offset from the first axis (fig 1, first axis is horizontal along the center of the engine in the solid lines configuration and second is along the vertical at the center of 3).
Regarding claim 16, Many as modified by Woodward discloses wherein the gas turbine engine core further includes a second rotating structure; the second rotating structure includes a compressor rotor within the compressor section and a second turbine rotor (col 2, line 66- col 3, line 7, Woodward) within the turbine section.
Claims 3 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Many as modified by Woodward in claim 1, further in view of Murrow (10710735).
Regarding claim 3, Many as modified by Woodward does not explicitly disclose wherein the second propulsor rotor comprises a plurality of fixed pitch rotor blades.
Murrow teaches a VTOL aircraft (10, fig 1), wherein the vertical fans can use fixed pitch rotor blades (col 8, lines 1-10).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used the fixed pitch rotor blades on the vertical fan of Many as modified by Woodward based on the teachings of Murrow. One of ordinary skill in the art would recognize that the fixed pitch fan blades would be the simplest to produce and the most reliable blade type.
Regarding claim 15, Many as modified by Woodward does not disclose wherein the second propulsor rotor is one of a plurality of second propulsor rotors rotatably driven by the rotating structure during the second mode.
Murrow teaches a VTOL aircraft (10, fig 1), wherein an engine can be used to drive a plurality of second propulsor rotors (48, 50, 58, fig 2).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a plurality of second propulsor rotors based on the teachings of Murrow. One of ordinary skill in the art would recognize that using multiple propulsors can help balance forces along a VTOL making the vertical flight more stable.
Claims 4-6 are rejected under 35 U.S.C. 103 as being unpatentable over Many as modified by Woodward in claim 1, further in view of Niergarth (10443412).
Regarding claim 4, Many discloses wherein the first propulsor rotor is rotatable about an axis (shaft S, fig 7); and an angle between a chord line of the first blade in the thrust position and the axis can be decreased from 90 degrees to increase power.
Many as modified by Woodward does not disclose wherein the angle is less than 60 degrees when powered.
Niergarth teaches adjusting fan blade angle so that the maximum angle can be adjusted by 90 degrees in either direction from neutral (col 6, lines 7-26).
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 pitch change angle disclosed by Many as modified by Woodward by having the pitch be less than 60 degrees in a thrust position based on the teachings of Niergarth. One of ordinary skill in the art would recognize that adjusting pitch angle would increase engine efficiency
Regarding claim 5, Many as modified by Woodward discloses wherein the first propulsor rotor is rotatable about an axis (S, fig 7); and an angle between a chord line of the first blade in the idle position and the axis is variable (page 1, line 107 to page 2, line 18).
Woodward as modified by Many does not disclose wherein an angle between a chord line of the first blade in the idle position and the axis is greater than seventy degrees.
Niergarth teaches adjusting fan blade angle so that the maximum angle can be adjusted by 90 degrees in either direction from neutral (col 6, lines 7-26), which means that the angle between the chord line of the first blade in an idle position and the axis can be up to 90 degrees which is greater than 70 degrees.
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 pitch change angle disclosed by Woodward by having the pitch be greater than 70 degrees in an idle position based on the teachings of Niergarth. One of ordinary skill in the art would recognize that adjusting pitch angle to an idle position would allow for power to be fully directed elsewhere when needed.
Regarding claim 6, Many as modified by Woodward does not disclose wherein the first blade pivots at least twenty degrees between the forward thrust position and the idle position.
Niergarth teaches adjusting fan blade angle so that the maximum angle can be adjusted by 90 degrees in either direction from neutral (col 6, lines 7-26).
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 pitch change angle disclosed by Many as modified by Woodward by having the pitch pivot at least 20 degrees in a thrust position based on the teachings of Niergarth. One of ordinary skill in the art would recognize that adjusting pitch angle would increase engine efficiency.
Claims 17 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Gilbert (3483696) in view of Niergarth (10443412) and Larrabee (US-Pub 2012/0329593).
Regarding claim 17, Gilbert discloses a propulsion system for an aircraft, comprising: a gas turbine engine core including a compressor section (31, fig 3), a combustor section (33, fig 3), a turbine section (34, 35, 36, fig 3) and a rotating structure (53 and 36, fig 3), the rotating structure comprising a shaft extending along a core axis (along 41, fig 3) turbine rotor within the turbine section; a first propulsor rotor (46, fig 3) coupled to the rotating structure during a first mode and a second mode, the first propulsor rotor rotatable about an axis (42, fig 3) and comprising a plurality of variable pitch blades (45, fig 1), the plurality of variable pitch blades comprising a first blade movable between a first position during the first mode and a second position during the second mode, and a second angle between the chord line of the first blade in the second position and the axis greater than seventy degrees (col 3, lines 50-62, the blade pitch is described as being a fine pitch, which one of ordinary skill in the art would recognize to be close to 90 degrees with reference to the axis of rotation), and the first propulsor rotor comprising a ducted rotor (47, fig 3); a second propulsor rotor (12, fig 1), the second propulsor rotor comprising an open rotor; and a transmission (60, fig 3) configured to couple the rotating structure to the second propulsor rotor during the second mode, the transmission coupled to the shaft of the rotating structure (via 55, fig 3), wherein the first mode is a horizontal flight mode and the second mode is a vertical flight mode, and wherein the first propulsor rotor is configured to generate thrust during the first mode and generate substantially no thrust during the second mode (Gilbert is a helicopter which is known for its ability to fly vertically and fly horizontally, in which case there would be no forward thrust in the vertical mode).
Gilbert does not disclose wherein the angle is less than 60 degrees when powered, and using a clutch less transmission.
Niergarth teaches adjusting fan blade angle so that the maximum angle can be adjusted by 90 degrees in either direction from neutral (col 6, lines 7-26).
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 pitch change angle disclosed by Gilbert by having the pitch be less than 60 degrees in a thrust position based on the teachings of Niergarth. One of ordinary skill in the art would recognize that adjusting pitch angle would increase engine efficiency.
Larrabee teaches using a clutch less transmission in a gas turbine engine (par. 0008).
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 transmission disclosed by Gilbert by having a clutch less transmission based on the teachings of Larrabee. Doing so would reduce friction losses within the transmission (par. 0007), as suggested by Larrabee.
Regarding claim 18, Gilbert discloses wherein the first propulsor rotor is configured to generate propulsive power in a first direction during the first mode; and the second propulsor rotor is configured to generate propulsive power in a second direction during the second mode (fig 1, the rotors are directed in two different directions).
Claim(s) 19 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Gilbert in view of Larrabee.
Regarding claim 19, Gilbert discloses a propulsion system for an aircraft, comprising: a gas turbine engine core including a compressor section (31, fig 3), a combustor section (33, fig 3), a turbine section (34, 35, 36, fig 3) and a rotating structure (53, 36, fig 3), the rotating structure comprising a turbine rotor (36, fig 3) within the turbine section; a first propulsor rotor (43, fig 3) rotatably driven by the rotating structure during a first mode and a second mode, the first propulsor rotor configured to generate horizontal thrust during the first mode, and the first propulsor rotor configured to generate substantially no thrust during the second mode, and the first propulsor rotor comprising a ducted rotor; and a second propulsor rotor rotatably driven by the rotating structure during the second mode, the second propulsor rotor configured to generate vertical lift during the second mode (col 3, lines 40-75), the second propulsor rotor coupled to a gear system (17, fig 1 is a differential drive unit, which would have a gear system to transmit forces in the differential); and a transmission (60, fig 3) configured to selectively couple the rotating structure to the second propulsor rotor, an output of the transmission connected to an input of the gear system through a transmission output shaft (20, fig 3, the line 20 leads from the engine 22 in fig 1 to the gear system 17), wherein the first mode is a horizontal flight mode and the second mode is a vertical flight mode (Gilbert is a helicopter, which is known for being able to fly horizontally or hover).
Gilbert does not disclose using a clutch less transmission.
Larrabee teaches using a clutch less transmission in a gas turbine engine (par. 0008).
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 transmission disclosed by Gilbert by having a clutch less transmission based on the teachings of Larrabee. Doing so would reduce friction losses within the transmission (par. 0007), as suggested by Larrabee.
Regarding claim 20, Gilbert discloses wherein the first propulsor rotor comprises a plurality of variable pitch blades (45, fig 3); and the plurality of variable pitch blades comprise a first blade configured to pivot between a thrust position during the first mode and an idle position during the second mode (col 3, lines 40-75).
Response to Arguments
Applicant’s arguments, see Remarks, filed 8/6/2025, with respect to the rejection(s) of claim(s) 1-16 under Woodward as modified by Many have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Many and Woodward.
Applicant's arguments filed 10/14/2025 have been fully considered but they are not persuasive. Applicant arguments that Gilbert does not disclose a hover mode are not persuasive, as Gilbert is a helicopter which is capable of vertical flight, meaning its horizontal engines would provide zero thrust during that flight regime.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SEAN V MEILLER whose telephone number is (571)272-9229. The examiner can normally be reached 7am-5pm.
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/SEAN V MEILLER/Examiner, Art Unit 3741 /DEVON C KRAMER/Supervisory Patent Examiner, Art Unit 3741