US 9,809,300 B1
Torque-sensitive locking and release mechanism for a bistable pitch propeller
Steffen Kuentzel, San Francisco, CA (US); and Damon Vander Lind, Oakland, CA (US)
Assigned to Kitty Hawk Corporation, Mountain View, CA (US)
Filed by Kitty Hawk Corporation, Mountain View, CA (US)
Filed on Mar. 20, 2017, as Appl. No. 15/463,989.
Int. Cl. B64C 11/34 (2006.01); B64C 29/00 (2006.01); F16D 15/00 (2006.01); F16D 7/00 (2006.01); B64C 11/32 (2006.01); F04D 29/36 (2006.01); F04D 15/00 (2006.01); B63H 3/00 (2006.01); B63H 1/06 (2006.01)
CPC B64C 11/343 (2013.01) [B63H 1/06 (2013.01); B63H 3/002 (2013.01); B64C 11/325 (2013.01); B64C 29/0033 (2013.01); F04D 15/0055 (2013.01); F04D 29/366 (2013.01); F16D 7/005 (2013.01); F16D 15/00 (2013.01); F05D 2260/77 (2013.01); F05D 2260/78 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A bistable pitch propeller, comprising:
a clutch module, which includes a ball, a detent, and a Belleville spring, that is configured to:
in response to a torque that is applied to the clutch module not exceeding a torque threshold, lock the clutch module, including by using the Belleville spring to press the ball into the detent; and
in response to the torque that is applied to the clutch module exceeding the torque threshold, release the clutch module, including by popping the ball out of the detent; and
a blade that is configured to:
be at a first pitch angle in response to the clutch module being locked; and
have a range of motion which extends from the first pitch angle to a second pitch angle in response to the clutch module being released.