US 12,441,464 B1
Rotor system for electrically powered rotorcraft
Brian L. Hinman, Carmel Valley, CA (US); and Muhammad Mubeen Javaid, Punjab (PK)
Assigned to SiFly Aviation, Inc., Monte Sereno, CA (US)
Filed by SiFly Aviation, Inc., Monte Sereno, CA (US)
Filed on Dec. 12, 2023, as Appl. No. 18/537,397.
Application 18/537,397 is a continuation in part of application No. 18/220,720, filed on Jul. 11, 2023, granted, now 12,049,305.
Application 18/220,720 is a continuation in part of application No. 18/306,108, filed on Apr. 24, 2023, granted, now 11,964,771.
Application 18/306,108 is a continuation in part of application No. 17/015,558, filed on Sep. 9, 2020, granted, now 11,634,235, issued on Apr. 25, 2023.
Claims priority of provisional application 63/359,944, filed on Jul. 11, 2022.
Claims priority of provisional application 62/897,688, filed on Sep. 9, 2019.
Int. Cl. B64C 27/57 (2006.01); B64C 11/30 (2006.01); B64C 27/59 (2006.01); B64C 27/80 (2006.01)
CPC B64C 27/57 (2013.01) [B64C 11/308 (2013.01); B64C 27/59 (2013.01); B64C 27/80 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A rotor system for a contra-rotating rotorcraft comprising:
a rotor hub coupled to an electric drive motor, a first set of rotor blades, and a second set of rotor blades;
a cyclic pitch adjustment mechanism coupled to the first set of rotor blades and configured to cause adjustment of the cyclic pitch of the first set of rotor blades;
a torque activated biasing mechanism configured to cause mechanical adjustment of a collective pitch of the second set of rotor blades based on a function of a torque applied to the rotor hub by the electric drive motor; wherein the function has a threshold torque such that when the applied torque is greater than the threshold torque adjustment of the collective pitch of the second set of rotor blades occurs.