US 11,926,408 B2
Failsafe valve for geared rotary actuator
Lowell Van Lund Larson, Huntington Beach, CA (US); and Robert Justin Sielaff, Holland, NY (US)
Assigned to Moog Inc., Elma, NY (US)
Appl. No. 17/420,432
Filed by MOOG INC., Elma, NY (US)
PCT Filed Jan. 27, 2020, PCT No. PCT/US2020/015227
§ 371(c)(1), (2) Date Jul. 2, 2021,
PCT Pub. No. WO2020/209924, PCT Pub. Date Oct. 15, 2020.
Claims priority of provisional application 62/797,927, filed on Jan. 28, 2019.
Prior Publication US 2022/0081103 A1, Mar. 17, 2022
Int. Cl. B64C 13/42 (2006.01); F15B 20/00 (2006.01); F15B 13/04 (2006.01)
CPC B64C 13/42 (2013.01) [F15B 20/002 (2013.01); F15B 20/004 (2013.01); F15B 2013/0409 (2013.01); F15B 2013/0413 (2013.01); F15B 2211/3058 (2013.01); F15B 2211/31547 (2013.01); F15B 2211/31594 (2013.01); F15B 2211/41581 (2013.01); F15B 2211/7058 (2013.01); F15B 2211/7107 (2013.01); F15B 2211/8623 (2013.01); F15B 2211/8633 (2013.01); F15B 2211/8752 (2013.01); F15B 2211/8757 (2013.01)] 16 Claims
OG exemplary drawing
 
1. An actuation system for displacing a movable member relative to a fixed member, the movable member having a failsafe position and being displaceable away from the failsafe position, the actuation system comprising:
an actuator connecting the movable member to the fixed member;
a hydraulic system having a hydraulic supply line, a first hydraulic control line, a second hydraulic control line, and a hydraulic return line;
a hydraulic rotary motor powered by the hydraulic system and arranged to drive the actuator to displace the movable member relative to the fixed member, the hydraulic rotary motor including a first control port in hydraulic communication with the first hydraulic control line, a second control port in hydraulic communication with the second hydraulic control line, and a return port in hydraulic communication with the hydraulic return line; and
a failsafe valve in hydraulic communication with the hydraulic system and the hydraulic rotary motor, the failsafe valve being operably connected to the movable member;
wherein the failsafe valve has a non-activated state when hydraulic pressure in the hydraulic supply line is greater than or equal to a predetermined normal pressure and an activated state when hydraulic pressure in the hydraulic supply line is less than the predetermined normal pressure;
wherein, when the failsafe is in the non-activated state, the first hydraulic control line is in hydraulic communication with the first control port of the hydraulic rotary motor, the second hydraulic control line is in hydraulic communication with the second control port of the hydraulic rotary motor, and the return port of the hydraulic rotary motor is in hydraulic communication with the hydraulic return line, such that the hydraulic rotary motor operates normally;
wherein, when the failsafe valve is in the activated state and the movable member is away from the failsafe position, the first hydraulic control line and the first control port of the hydraulic rotary motor, or the second hydraulic control line and the second control port of the hydraulic rotary motor, are in hydraulic communication with the hydraulic return line.
 
12. A method of operating an actuation system for displacing a movable member relative to a fixed member, the movable member having a failsafe position and being displaceable away from the failsafe position, the actuation system comprising an actuator connecting the movable member to the fixed member, a hydraulic system, and a hydraulic rotary motor powered by the hydraulic system and arranged to drive the actuator to displace the movable member relative to the fixed member, the method comprising:
A) providing a failsafe valve in hydraulic communication with the hydraulic system and the hydraulic rotary motor;
B) providing a mechanical connection between the failsafe valve and the movable member;
C) providing hydraulic communication between a first hydraulic control line of the hydraulic system and a first control port of the hydraulic rotary motor, between a second hydraulic control line of the hydraulic system and a second control port of the hydraulic rotary motor, and between a return line of the hydraulic system and a return port of the hydraulic rotary motor, when the hydraulic pressure in the hydraulic supply line is greater than or equal to a predetermined normal pressure; and
D) operating the failsafe valve by way of the mechanical connection to provide hydraulic communication between the first control port of the hydraulic rotary motor and the return line of the hydraulic system, or between the second control port of the hydraulic rotary motor and the return line of the hydraulic system, when the hydraulic pressure in the hydraulic supply line is less than or equal to the predetermined normal pressure and the movable member is away from the failsafe position.