US 11,655,880 B2
Multi-speed gear box for a rotary wing aircraft
Bruce D. Hansen, Shelton, CT (US)
Assigned to LOCKHEED MARTIN CORPORATION, Bethesda, MD (US)
Filed by LOCKHEED MARTIN CORPORATION, Bethesda, MD (US)
Filed on Jul. 8, 2020, as Appl. No. 16/923,445.
Prior Publication US 2022/0010862 A1, Jan. 13, 2022
Int. Cl. F16H 3/34 (2006.01); B64C 27/14 (2006.01); B64C 27/06 (2006.01)
CPC F16H 3/34 (2013.01) [B64C 27/06 (2013.01); B64C 27/14 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A gear system for a rotary wing aircraft comprising:
a first gear including an inner gear portion having a first pitch and an outer gear portion having a second pitch that is distinct from the first pitch;
a second gear including a third pitch which is driven at a driving rotational speed;
an actuator coupled to the second gear while the second gear is driven at the driving rotational speed, the actuator configured to shift the second gear along a radius of the first gear to selectively engage with one of the inner gear portion and the outer gear portion to drive the first gear at a first rotational speed, and to selectively engage with the other of the inner gear portion and the outer gear portion to drive the first gear at a second rotational speed other than the first rotational speed;
a controller operable to selectively control the actuator to shift the second gear between the inner gear portion and the outer gear portion
a first sensor mounted to the first gear and operably connected to the controller; and
a second sensor mounted to the second gear and operably connected to the controller, the controller being operable to determine a rotational position of the second gear relative to the first gear.