DETAILED ACTION
Response to Arguments
Applicant’s arguments, see Remarks, filed 15 September 2026, with respect to the rejection(s) of claim(s) 11-12 and 15-18 under 35 USC 103 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 Therefore, the rejection has been withdrawn.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 Calkins et al (US 20190031319 A1; also US 12,065,234 B2) and Hawkins et al (US 20200072193 A1; also US 11,466,664 B2).
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) 11-12 and 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Calkins et al – hereafter Calkins – (US 20190031319 A1; also US 12,065,234 B2) in view of Hawkins et al – hereafter Hawkins – (US 20200072193 A1; also US 11,466,664 B2).
Regarding claim 11, Calkins teaches an apparatus (Fig.1-6) comprising:
a fan pitch actuation system (202) coupled to a blade (150) of a propeller, the fan pitch actuation system moveable in a first direction to rotate the blade from a first pitch angle to a second pitch angle based on an amount of hydraulic fluid pumped into the fan pitch actuation system (Fig.3; ¶56);
a fluid supply/reservoir (212) to store the hydraulic fluid;
a valve (240/242) coupled to an output (via 218) of the fluid supply/reservoir and an input of the fan pitch actuation system (¶72, note “the pitch hydraulic fluid exiting the protective control valve 240 flows downstream to the oil transfer bearing 186 of the pitch actuation assembly 202”), the valve to, when open provide the hydraulic fluid from the fluid supply/reservoir to the fan pitch actuation system based on a control signal (¶70-71); and
a controller (250) to:
detect a triggering event (¶83, note “control valve 230 fails, becomes unresponsive, or erroneously drives the pitch of the propeller blades 150 toward a fine pitch position”) ; and
based on at least one of user preferences, flight characteristics, or engine characteristics, output the control signal to open the valve based on the detected triggering event (¶83, note “the protective control valve 240 takes over operation of governing overspeed conditions as well as feathering the propeller blades 150 to a full feather position. The controller 250 then utilizes the protective speed sensor 244 and may use the protective blade angle feedback sensor 246 in conjunction with the protective control valve 240 to control the propeller assembly 106”).
Calkins does not explicitly teach an accumulator to store the hydraulic fluid, the valve, to when open, cause the accumulator to discharge the stored hydraulic fluid to the fan pitch actuation system.
Hawkins teaches a controllable pitch blade actuation system (¶2). Hawkins further teaches (Fig.5) the controllable pitch propeller actuation system including multiple valves (V1/V2), a fluid supply (15) with hydraulic fluid and an accumulator (151/152) that further stores pressurized hydraulic fluid to be used in controlling the pitch of the propeller. This configuration provides a fail-safe emergency pitch system (¶9-10).
It would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify the apparatus of Calkins by having an accumulator to store the hydraulic fluid, the valve, to when open, cause the accumulator to discharge the stored hydraulic fluid to the fan pitch actuation system based on the teachings of Hawkins because this configuration provides a fail-safe emergency pitch system.
Regarding claim 12, Calkins and Hawkins further teach the triggering event is at least one of a malfunction or an error (Calkins ¶83, note “in the event the primary control valve 230 fails, becomes unresponsive, or erroneously drives the pitch of the propeller blades 150 toward a fine pitch position, the protective control valve 240 takes over operation of governing overspeed conditions as well as feathering the propeller blades 150 to a full feather position”).
Regarding claim 15, Calkins and Hawkins further teach a reservoir to store the hydraulic fluid output from the fan pitch actuation system (Calkins ¶65, note lines 224 are drain lines where the hydraulic fluid can be scavenged to the hydraulic fluid supply 212).
Claim(s) 16-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Calkins and Hawkins as applied to claim 15 above, and further in view of Amerling et al (US 6,261,062 B1).
Regarding claim 16, Calkins and Hawkins teach all the limitations of claim 15, see above, and further teach the valve is a first valve, wherein the apparatus further includes:
a hydraulic source (Calkins Fig.3, 210) coupled to the reservoir, the hydraulic source to receive the hydraulic fluid from the reservoir (Calkins Fig.3);
however, do not teach a second valve coupled to the hydraulic source and the accumulator, the second valve to, when open, cause the hydraulic fluid in the hydraulic source to flow into the accumulator.
Amerling teaches a controllable pitch propeller actuation system (column 1 line 6-7). Amerling further teaches (Fig.4) the controllable pitch propeller actuation system including multiple valves (210/240/242/251/252/253/254), a fluid supply (42) with hydraulic fluid (44) and an accumulator (200) that further stores pressurized hydraulic fluid to be used in controlling the pitch of the propeller; a hydraulic source (40) coupled to a reservoir (42); a second valve (240) coupled to the hydraulic source and the accumulator, the second valve to, when open, cause the hydraulic fluid in the hydraulic source to flow into the accumulator (Fig.4). This configuration allows, with other elements, monitoring a system pressure and control the hydraulic source operation (column 10 line 35-41).
It would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to further modify the apparatus of Calkins and Hawkins by having a second valve coupled to the hydraulic source and the accumulator, the second valve to, when open, cause the hydraulic fluid in the hydraulic source to flow into the accumulator based on the teachings of Amerling because this configuration allows, with other elements, monitoring a system pressure and control the hydraulic source operation.
Regarding claim 17, Calkins, Hawkins and Amerling further teach the controller is to output the control signal to a control coil (Calkins Fig.3, note 242 is an electrohydraulic servovalve which is controlled via control signals to a control coil), however, do not explicitly teach wherein the control signal being applied to the control coil causes the second valve to open. Note that Calkins’ control signal controls the first valve and the second valve of Amerling is a check valve.
However, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to further modify the apparatus of Calkins, Hawkins and Amerling by having the check valve being a valve with an electrohydraulic servovalve controller as disclosed by Calkins because this would provide better control features to the overall apparatus.
Regarding claim 18, Calkins and Hawkins teach all the limitations of claim 15, see above, and further teach the valve is a first valve and the fan pitch actuation system, the accumulator, and first valve is included in a first engine (Calkins Fig.3),
however, do not teach a second valve coupled to a hydraulic source and the accumulator, the second valve to, when open, cause the hydraulic fluid in the hydraulic source to flow into the accumulator, the hydraulic source being included in a second engine.
Amerling teaches a controllable pitch propeller actuation system (column 1 line 6-7). Amerling further teaches (Fig.4) the controllable pitch propeller actuation system including multiple valves (210/240/242/251/252/253/254), a fluid supply (42) with hydraulic fluid (44) and an accumulator (200) that further stores pressurized hydraulic fluid to be used in controlling the pitch of the propeller; a hydraulic source (40) coupled to a reservoir (42); a second valve (240) coupled to the hydraulic source and the accumulator, the second valve to, when open, cause the hydraulic fluid in the hydraulic source to flow into the accumulator,
This configuration allows, with other elements, monitoring a system pressure and control the hydraulic source operation (column 10 line 35-41).
It would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to further modify the apparatus of Calkins and Hawkins by having a second valve coupled to the hydraulic source and the accumulator, the second valve to, when open, cause the hydraulic fluid in the hydraulic source to flow into the accumulator based on the teachings of Amerling because this configuration allows, with other elements, monitoring a system pressure and control the hydraulic source operation.
With respect to the hydraulic source positioning, it has been held that if shifting the position of a component in a device would not have modified the operation of said device, said position shift of said component is unpatentable, additionally, a particular placement of a component in a device has been held to be an obvious matter of design choice. In the current instance, there is no evidence that having the hydraulic source being included in a second engine, would change the operation of the apparatus, therefore, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to further modify the apparatus of Calkins, Hawkins and Amerling by shifting the position/placement of the hydraulic source to be included in a second engine as an obvious matter of design choice (MPEP 2144.04 VI C).
Allowable Subject Matter
Claims 13-14 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JUAN G FLORES whose telephone number is (571)272-3486. The examiner can normally be reached Monday - Friday, 8:30am - 5:30pm Pacific Time.
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/JUAN G FLORES/Primary Examiner, Art Unit 3745
