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 .
Response to Arguments
Applicant's arguments filed 09/08/2025 have been fully considered but they are not persuasive.
Regarding the argument that “Hampton ex(p)ressly discloses that its flapping bearing 232, 234 are mounted within an interior of the central portion 204 of its yoke 202. Therefore it is clear that the flapping bearings 232, 234 of Hampton are not spaced outward from respective sides of its yoke 202.”
The Examiner respectfully notes that claim 1 requires, “at least one bearing disposed adjacent a side of the hub portion and spaced outward from the side of the hub portion” and does not require bearings to be spaced outward from respective sides of its yoke as argued by the Applicant.
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.
Claims 1-17 and 21-23 are rejected under 35 U.S.C. 103 as being unpatentable over Verna et al. (US PGPUB 2020/0385130 A1) in view of Hampton et al. (US Patent 10,308,356 B2).
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Regarding claim 1, Verna et al. discloses a propulsor assembly (Fig. 6), comprising:
a motor ([0017]);
a blade (112) driven by the motor (Fig. 6), the blade including:
a hub portion (206);
a first blade portion (Fig. 6, the blade is shown to have two portions) extending radially outward from the hub portion; and
a second blade portion (Fig. 6) extending radially outward from the hub portion;
However, Verna et al. does not teach or suggest, “a coupling assembly coupling the blade to a shaft of the motor such that the blade rotates together with the shaft about a first axis, the coupling assembly including at least bearing disposed adjacent a side of the hub portion and spaced outward from the side of the hub portion, the at least one bearing coupling the blade to the shaft of the motor,” or “wherein the at least one bearing, in response to pivoting of the blade about a second axis extending through the hub portion and oriented at an angle with respect to the first axis exerts a restoring force that urges the blade toward a neutral position.”
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Hampton et al. teaches, in the field of rotorcraft hubs, a rotorcraft hub assembly (12, 206 “mast bore” e.g., a hub) with a coupling assembly (Fig. 5) coupling the blade (214, 216) to a shaft (208) of the motor such that the blade rotates together with the shaft about the first axis (246), the coupling assembly including at least one bearing (232, 234) disposed adjacent to a side of the hub portion (Fig. 5, 206 the mast bore is being considered the hub as it is the portion of the assembly that rotates with the shaft) and spaced outward from the side of the hub portion (Fig. 5), the at least one bearing coupling the blade to the shaft of the motor (Fig. 5); wherein the at least one bearing, in response to pivoting of the blade about a second axis (230) extending through the hub portion (Fig. 5) and oriented at an angle with respect to the first axis (Fig. 4) in response to external forces applied to at least one of the first blade portion of the second blade portion of the blade (¶20), and a stiffness of the at least one bearing exerts a restoring force that urges the blade to a neutral position (¶20).
It would have been obvious to one of ordinary skill in the art before the effective filing date, to modify the propulsor assembly of Verna et al. to have the rotorcraft hub with the teeter mechanism of Hampton et al., as both references are in the same field of endeavor, and one of ordinary skill would appreciate that, “It may be advantageous to allow a pair of oppositely disposed rotor blades to flap or teeter in a seesaw motion about a teetering axis while the rotor hub assembly is rotating. Such flapping may be regulated by a flapping bearing disposed in the yoke between the pair of rotor blades. The flapping bearing may have radial and torsional spring rates that accommodate asymmetrical thrust between the pair of rotor blades as well as any Coriolis torque. (¶2)”
Regarding claim 2, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above, wherein the coupling assembly also includes:
a yoke (Hampton et al.; 202) coupled to the shaft of the motor (Hampton et al.; Fig. 4, Fig. 5), the yoke supporting the at least one bearing (Fig. 5; the yoke supports the bearings); and
a least one bracket (Hampton et al.; 274, 276) coupled to the hub portion of the blade (Hampton et al.; Fig. 5, Fig. 6, the Examiner notes that the brackets are coupled to the hub through yoke) and supported by the at least one bearing.
Regarding claim 3, the combination of Verna et al. and Hampton et al. teach all of claim 2 as above, wherein the at least one bracket includes:
a first arm portion fixed to an upper surface portion of the hub portion of the blade (Hampton et al., Fig. 6 shows the bracket 274 having a first arm portion attached to the upper surface portion of the hub);
a second arm portion fixed to a lower surface portion of the hub portion of the blade (Hampton et al., Fig. 6 shows the bracket 274 having a second arm portion attached to the lower surface portion of the hub); and
a base portion (Hampton et al., Fig. 6) extending from the first arm portion and the second arm portion, and coupled in the at least one bearing (Fig. 6; the base portion is the central portion of the bracket).
Regarding claim 4, the combination of Verna et al. and Hampton et al. teach all of claim 3 as above, wherein the at least one bearing is a torsional bearing (Hampton et al.; 232, 234, ¶20), including:
an elastomeric member (Hampton et al., ¶20 discloses elastomeric layers 240, 242) having an inner surface portion (Hampton et al.; 260, Fig. 5, Fig. 6, 4120 teaches that the flapping bearing are disposed about the trunnion arms 226, 228) defining a central opening (Hampton et al.; Fig. 5, Fig. 6) and an outer surface portion (Hampton et al., Fig. 5), wherein the base portion of the at least one bracket is coupled to one of the inner surface portion r the outer surface portion (Hampton et al., Fig. 6); and
a bearing housing (Hampton et al.; Fig. 5, the Examiner notes that the bearings appear to be held in a housing) fixed to the yoke (Hampton et al., Fig. 6), wherein the elastomeric member is coupled to the bearing housing (Hampton et al., Fig. 6).
Regarding claim 5, the combination of Verna et al. and Hampton et al. teach all of claim 4 as above, wherein the outer surface portion of the elastomeric member is fixedly coupled to an inner surface portion of the bearing housing (Hampton et al., Fig. 6), and the inner surface portion of the elastomeric member is fixedly coupled to an outer surface portion of the base portion of the at least one bracket (Hampton et al., Fig. 6).
Regarding claim 6, the combination of Verna et al. and Hampton et al. teach all of claim 4 as above, wherein the elastomeric member has at least one of a cylindrical or a conical geometry (Hampton et al.; Fig. 5).
Regarding claim 7, the combination of Verna et al. and Hampton et al. teach all of claim 4 as above,
wherein the base portion and the elastomeric member a concentrically arranges bout the second axis (Hampton et al., Fig. 5) such that, in response to a pivoting of the blade in a first rotational direction about the second axis (Hampton et al., ¶20):
the elastomeric member exerts a restoring force on the hub portion of the blade in a second rotational direction that is opposite the first rotational direction (Hampton et al., ¶20-¶21); and
a displacement of a tip end portion of the second blade portion of the blade is opposite and equal to a displacement of a tip end portion of the first blade portion of the blade (Hampton et al., Fig. 3).
Regarding claim 8, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above.
Verna et al. shows a monolithic blade in (Fig. 1, 112) including the hub portion, the first blade portion and the second blade portion formed as a single element; (the Examiner notes that this component has been replaced by the combination with Hampton et al. which shows the blades attached to the hub by trunnions (210, 212).
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify the rotor assembly of the combination of Verna et al. and Hampton et al. to have a monolithic blade including the hub portion, the first blade portion and the second blade portion formed as a single element, as one of ordinary skill would appreciate "that the use of a one piece construction instead of the structure disclosed in [the prior art] would be merely a matter of obvious engineering choice. (See MPEP 2144.04 V. B.)”.
Regarding claim 9, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above, wherein the pitch angle of the first blade portion and the second blade portion are not independently adjustable (Hampton et al.; Fig. 3, 244).
Regarding claim 10, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above, wherein the coupling assembly includes:
a first bracket (Hampton et al., 274) fixed to a first side portion of the hub portion of the blade (Hampton et al.; Fig. 5, Fig. 6);
a second bracket (Hampton et al., 276) fixed to a second side portion of the hub portion of the blade (Hampton et al.; Fig. 5, Fig. 6);
a first elastomeric bearing (Hampton et al., 232) coupled between the first bracket and a corresponding portion of a yoke (Hampton et al., 202) coupled to the shaft (Hampton et al., 208) of the motor; and
a second elastomeric bearing (Hampton et al., 234) coupled between the second bracket and a corresponding portion of the yoke (Hampton et al.; Fig. 5, Fig. 6).
Regarding claim 11, the combination of Verna et al. and Hampton et al. teach all of claim 10 as above, wherein at least one of the first elastomeric bearing or the second elastomeric bearing is a laminated bearing (Hampton et al.; Fig. 5, 232, 234 ¶20-¶21),
wherein a stiffness of the first elastomeric bearing and the second elastomeric bearing restricts a pivoting motion of the blade about the second axis to within a preset range (Hampton et al., ¶20-¶21), and wherein in response to a pivoting of the blade in a first rotation direction about the second axis, the first elastomeric bearing and the second elastomeric bearing exert a resorting force on the hub portion of the blade in a second rotation direction that is opposite the first rotational direction (Hampton et al., ¶20-¶21).
Regarding claim 12, the combination of Verna et al. and Hampton et al. teach all of claim 10 as above.
However, the combination of Verna et al. and Hampton et al. do not explicitly teach, “wherein a stiffness of the first elastomeric bearing and the second elastomeric bearing is in a range of between 120 Ft-Lbf/degree and 150 Ft-Lbf/degree.”
Hampton further teaches, in ¶2 “The flapping bearing may have radial and torsional spring rates that accommodate asymmetrical thrust between the pair of rotor blades as well as any Coriolis torque. While the radial and torsional spring rates of the flapping bearing may be tailored for these purposes, the flapping bearing may also have a propensity to move or deform in an axial direction along the teetering axis.” indicating the stiffness of the elastomeric bearings of Hampton et al. as a result effective variable in the changing the stiffness of these elastomeric to the expected forces (Coriolis torque and asymmetrical thrust).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to modify the propulsor assembly created by the combination of Verna et al. and Hampton et al. to have a stiffness of between 120 Ft-Lbf/degree and 150 Ft-Lbf/degree as a matter of routine optimization since it has been held that “where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). (See also MPEP 2144.05 II.).
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Regarding claim 13, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above, wherein a central axis of hub portion (Hampton et al., 230) of the blade corresponding to the second axis is offset from a central axis of the blade (Hampton et al., 294), the central axis of the blade corresponding to a span of the blade extending from a tip end portion of the first blade portion to a tip end portion of the second blade portion of the blade (Hampton et al., the span axis line 294 extends from tip to tip through the hub).
Regarding claim 14, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above, wherein the second axis is oriented at 45 degrees (Hampton et al., 126 “Angle 296 may be any angle, such as 90 degrees, 40 degrees, an acute angle of less than 60 degrees or another angle suitable for the application”) relative to a span of the blade (Hampton et al., 294) extending from a tip end portion of the blade portion to a tip end portion of the second blade portion of the blade (Hampton et al., Fig. 4).
Regarding claim 15, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above, wherein, in response to an external force applied to one of the first blade portion of the second blade portion:
the blade pivots about the second axis such that a plane of rotation of the blade is tilted relative to a plane of rotation of the blade in a neutral state (Hampton et al.; Fig. 3, 244, 21);
a degree of pivoting of the blade is restricted in response to a restoring force exerted by the at least one bearing (Hampton et al., 21); and
the restoring force exerted by the at least one bearing urges the blade back toward the neutral state (Hampton et al., ¶21).
Regarding claim 16, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above, wherein:
a leading edge of the first blade portion (Hampton et al.; Fig. 4, the leading edge is indicated by the direction of travel 246) is arranged in parallel to and offset from a trailing edge of the second blade portion in a chord direction of the blade (Hampton et al., Fig. 4);
a leading edge of the second blade portion (Hampton et al., Fig. 4) is arranged parallel to and offset from a trailing edge of the first blade portion in the chord direction of the blade (Hampton et al., Fig. 4);
the hub portion is defined between a root end portion of the first blade portion and a root end portion of the second blade portion (Hampton et al.; Fig. 4 the hub is between the root portions of the blades, 204); and
the hub portion is oriented at an angle (Hampton et al.; ¶26, 296) with respect to the leading edge of the first blade portion and the leading edge of the second blade portion (Hampton et al., Fig. 4), and defines substantially flat portions (Hampton et al., 210, 212) configured to be coupled to the coupling assembly (Hampton et al., Fig. 4).
Regarding claim 17, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above, wherein the propulsor assembly comprises four lift propulsor assemblies (Verna et al., Fig. 6 shows 4 propulsors) included on an electric (Verna et al., ¶17) vertical takeoff and landing aircraft (Verna et al., ¶37) each generating thrust (Vernal et al., ¶37).
Regarding claim 21, the combination of Verna et al. and Hampton et al. teach all of claim 1 as above,
wherein the at least one bearing is a first bearing (232) and the side of the hub portion is a first side (Hampton et al., Fig. 5; the Examiner notes there are two bearings opposite of the hub 206), the coupling assembly further including:
a second bearing (234) disposed adjacent a second side of the hub portion and spaced outward from the second side of the hub portion (Hampton et al., Fig. 5; the Examiner notes there are two bearings opposite of the hub 206), the second side opposite the first side (Hampton et al., Fig. 5);
a yoke (Hampton et al., 202) coupled to the shaft of the motor, the yoke supporting the first bearing and the second bearing (Hampton et al., Fig. 5);
a first bracket (Hampton et al.; 274, Fig. 5) coupled to hub portion at the first side and supported by the first bearing; and
a second bracket (Hampton et al.; 276, Fig. 5) coupled to the hub portion at the second side and supported by the second bearing.
Regarding claim 22, the combination of Verna et al. and Hampton et al. teach all of claim 21 as above,
wherein the first bracket is coupled to an upper surface portion of the hub portion (Hampton et al.; Fig. 5, the brackets are coupled to the entirety of the hub portion), to a lower surface portion (Hampton et al.; Fig. 5, the brackets are coupled to the entirety of the hub portion) of the hub portion, and to the first bearing (Hampton et al., Fig. 5), and
wherein the second bracket is coupled to the upper surface portion of the hub portion (Hampton et al.; Fig. 5, the brackets are coupled to the entirety of the hub portion), to the lower surface portion of the hub portion ((Hampton et al.; Fig. 5, the brackets are coupled to the entirety of the hub portion), and to the second bearing (Hampton et al., Fig. 5).
Regarding claim 23, the combination of Verna et al. and Hampton et al. teach all of claim 21 as above,
wherein the coupling assembly further includes:
a first elastomeric member (Hampton et al.; 232, the Examiner notes that the bearings are laminated elastomeric bearings) coupled to the first bracket and to a housing of the first bearing (Hampton et al., Fig. 5); and
a second elastomeric member (Hampton et al.; 234, the Examiner notes that the bearings are laminated elastomeric bearings) coupled to the second bracket and to a housing of the second bearing (Hampton et al., Fig. 5),
wherein the first elastomeric member of the first bearing and the second elastomeric member of the second bearing exert respective torsional forces that urge the blade toward the neutral position (Hampton et al., ¶21).
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 RYAN C CLARK whose telephone number is (571)272-2871. The examiner can normally be reached Monday - Thursday 0730-1730, Alternate Fridays 0730-1630.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Courtney D Heinle can be reached at (571)-270-3508. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/R.C.C./ Examiner, Art Unit 3745
/COURTNEY D HEINLE/ Supervisory Patent Examiner, Art Unit 3745