The split torque gearbox is a practical solution to the transmission of high torques with the lowest possible weight. In this article, we perform the mathematics necessary to calculate possible solutions for the simultaneous meshing of four wheels on the basis of geometric conditioning factors. These calculations will be illustrated by numerical applications. Finally, particular cases of planetary gearboxes and a gearbox with equal idler pinions are studied, with the conclusion that their application is appropriate in specific conditions.

1.
Gmirya
,
Y.
, 2003, “
Split-Torque Face Gear Transmission
,” Sikorsky Aircraft Corporation, U.S. Patent No. 6,612,195.
2.
Craig
,
G. A.
,
Heath
,
G. F.
, and
Sheth
,
V. J.
, 1998, “
Split Torque Proprotor Transmission
,” McDonnell Douglas Helicopter Co., U.S. Patent No. 5,823,470.
3.
Filler
,
R. R.
,
Heath
,
G. F.
,
Slaughter
,
S. C.
, and
Lewicki
,
D. G.
, 2002, “
Torque Splitting by a Concentric Face Gear Transmission
,”
Proceedings of the 58th Annual Forum of the American Helicopter Society
, Montreal, Canada, Jun. 11–13.
4.
Litvin
,
F. L.
,
Wang
,
J. C.
,
Bossler
,
R. B.
,
Chen
,
Y. J. D.
,
Heath
,
G.
, and
Lewicki
,
D. G.
, 1994, “
Application of Face Gear Drives in Helicopter Transmissions
,”
ASME J. Mech. Des.
0161-8458,
116
(
3
), pp.
672
676
.
5.
Bechhoefer
,
E.
,
Li
,
R.
, and
He
,
D.
, 2009, “
Quantification of Condition Indicator Performance on a Split Torque Gearbox
,”
J. Intell. Manuf.
0956-5515, in press.
6.
Southcott
,
B.
, 1999 “
Gear Arrangement
,” Adelaide Gear Pty. Ltd., U.S. Patent No. 5,896,775.
7.
Gmirya
,
Y.
, 2005, “
Split Torque Gearbox With Pivoted Engine Support
,” Sikorsky Aircraft Corp., U.S. Patent No. 6,883,750.
8.
Kish
,
J. G.
, 1993, “
Sikorsky Aircraft Advanced Rotorcraft Transmission (ART) Program
,” Report No. NASA CR-191079, ARL-CR-49.
9.
Henriot
,
G.
, 1979,
Traité théorique et pratique des engrenages (I)
, 6th ed.,
Dunod
,
Paris, France
, pp.
587
662
.
10.
Parker
,
R. G.
, and
Lin
,
J.
, 2004, “
Mesh Phasing Relationships in Planetary and Epicyclic Gears
,”
ASME J. Mech. Des.
0161-8458,
126
(
2
), pp.
365
370
.
11.
Akinori
,
F.
,
Kuniaki
,
S.
, and
Mitsuoki
,
M.
, 2001, “
Drive Transmission Apparatus for Twin-Screw Extruder
,” Toshiba Kikai Kabushiki Kaisha, U.S. Patent No. 6,298,751.
12.
Krantz
,
T. L.
, and
Rashidi
,
M.
, 1995, “
Vibration Analysis of a Split Path Gearbox
,”
31st Joint Propulsion Conference
, San Diego, CA, Jul. 10–12.
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