US 12,480,567 B2
Harmonic gear systems having redundant load paths between input and output shafts
Derick Balsiger, Prescott Valley, AZ (US); and Keith A. Bloxham, Gilbert, AZ (US)
Assigned to HAMILTON SUNDSTRAND CORPORATION, Charlotte, NC (US)
Filed by Hamilton Sundstrand Corporation, Charlotte, NC (US)
Filed on Feb. 16, 2024, as Appl. No. 18/443,864.
Prior Publication US 2025/0264152 A1, Aug. 21, 2025
Int. Cl. F16H 49/00 (2006.01); F16C 19/18 (2006.01)
CPC F16H 49/001 (2013.01) [F16C 19/18 (2013.01); F16C 2361/00 (2013.01); F16H 2049/003 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A harmonic gear system, comprising:
a housing having forward and aft ends;
an input shaft having a forward end that is forward of the housing, and an aft end that is within the housing, wherein the aft end defines a wave generator;
a wave generator bearing surrounding the wave generator;
first and second cup-shaped flex splines,
wherein the second flex spline is nested within the first flex spline, and the first and second flex splines are grounded to the forward end of the housing, and the first and second flex splines are simultaneously biased by the wave generator via the wave generator bearing;
an output shaft having a forward end that is within the housing and an aft end that is aft of the housing, and a radial flange at the forward end;
first and second circular splined shafts, within the housing, wherein the second circular splined shaft is nested within the first circular splined shaft, and the first and second circular splined shafts are connected to the radial flange of the output shaft and are driven by ones of the first and second flex splines, to thereby drive the output shaft; and
a bearing between the first and second circular splined shafts.