US 12,140,213 B2
Compound harmonic gear system with dual output arms
Derick S. Balsiger, Prescott Valley, AZ (US); and Andrzej Ernest Kuczek, Bristol, CT (US)
Assigned to HAMILTON SUNDSTRAND CORPORATION, Charlotte, NC (US)
Filed by Hamilton Sundstrand Corporation, Charlotte, NC (US)
Filed on Aug. 11, 2021, as Appl. No. 17/399,289.
Prior Publication US 2023/0048660 A1, Feb. 16, 2023
Int. Cl. F16H 49/00 (2006.01); B64C 13/34 (2006.01)
CPC F16H 49/001 (2013.01) [B64C 13/34 (2013.01); F16H 2049/003 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A gear system, comprising:
first and second ground gear;
a drive shaft disposed along a rotation axis of the gear system and configured to rotate about the rotation axis; and
an output gear supported by the first and second ground gear and configured to rotate by engagement between a wave generator portion of the drive shaft, a wave generator bearing, a flex spline, the output gear and the first and second ground gear,
the output gear defining:
an output gear body; and
first and second output arms respectively extending radially outward from opposite sides of the output gear body to respectively define first and second radial inner ends and radial outer ends of the first and second output arms, so that the first and second radial outer ends are disposed on a radial axis that extends through a radial center of the gear system;
wherein:
the first ground gear defines a first ground gear body that is ring shaped, the first ground gear body defines a first ground gear aperture boundary, which defines a first ground gear aperture through which the wave generator portion of the drive shaft, the wave generator bearing and the flex spline extend, the first ground gear is disposed on a first side of the output gear along the rotation axis;
the second ground gear is disposed on a second side of the output gear along the rotation axis, wherein the first and second ground gears are connected to each other with the output gear therebetween along the rotation axis, the second ground gear is a same shape as the first ground gear such that the second ground gear defines: a second ground gear body with a second ground gear aperture boundary that defines a second ground gear aperture;
the first and second ground gear respectively include mounting features disposed on the radial axis that are configured to mount to a movable component; and
the first ground gear includes a first set of mount segments, including first and second mount segments, that extend along the rotation axis from the first ground gear body, and are circumferentially spaced apart from each other about the first ground gear body and to define rotation limiters for the first and second output arms, and that are configured to mount to a stationary component.