In the Milner continuously variable transmission altering the axial separation between two moveable halves of the outer race set allows the radial position of the planet balls to vary, along with the contact positions on the inner and outer races and, hence, the transmission ratio changes. An inelastic analytical model implemented in SIMULINK is presented which allows the component positions, speeds, forces, and torques to be calculated. Use of a free body approach for individual components allows both individual and coupled component motions to be studied. Examples of the steady-state results and experimental verification are presented. Use of the model for dynamic investigations and to improve future versions of the transmission is discussed.

1.
Hewko
,
L. O.
, 1986, “
Automotive Traction Drive CVTs—An Overview
,” SAE Paper No. 861355.
2.
Akehurst
,
S.
,
Parker
,
D. A.
, and
Schaaf
,
S.
, 2006, “
CVT Traction Drives—A Review of Research Into Their Design, Functionality and Modeling
,”
ASME J. Mech. Des.
1050-0472,
128
, pp.
1165
1176
.
3.
Akehurst
,
S.
,
Vaughan
,
N. D.
,
Parker
,
D. A.
, and
Simner
,
D.
, 2004, “
Modelling of Loss Mechanisms in a Pushing Metal V-belt CVT. Part I: Torque Losses due to Band Friction
,”
Proc. Inst. Mech. Eng., Part D (J. Automob. Eng.)
0954-4070,
218
, pp.
1269
1281
.
4.
Akehurst
,
S.
,
Vaughan
,
N. D.
,
Parker
,
D. A.
, and
Simner
,
D.
, 2004, “
Modelling of Loss Mechanisms in a Pushing Metal V-belt CVT. Part 2: Pulley Deflection Losses and Total Torque Loss Validation
,”
Proc. Inst. Mech. Eng., Part D (J. Automob. Eng.)
0954-4070,
218
, pp.
1283
1293
.
5.
Akehurst
,
S.
,
Vaughan
,
N. D.
,
Parker
,
D. A.
, and
Simner
,
D.
, 2004, “
Modelling of Loss Mechanisms in a Pushing Metal V-belt CVT. Part 3: Belt Slip Losses
,”
Proc. Inst. Mech. Eng., Part D (J. Automob. Eng.)
0954-4070,
218
, pp.
1295
1306
.
6.
Akehurst
,
S.
,
Brace
,
C. J.
,
Vaughan
,
N. D.
,
Milner
,
P.
, and
Hosoi
,
Y.
, 2001, “
Performance Investigations of a Novel Rolling Traction CVT
,” SAE Paper No. 2001-01-0874.
7.
World Patent number: WO9935417, “
A Continuously Variable Transmission Device
,” Publication date: 1999-07-15, Inventor: Milner Peter James (GB).
8.
Carbone
,
G.
,
Mangialardi
,
L.
, and
Mantriot
,
G.
, 2004, “
A Comparison of the Performances of Full and Half Toroidal Traction Drives
,”
Mech. Mach. Theory
0094-114X,
39
, pp.
921
942
.
9.
Yamamoto
,
T.
,
Matsuda
,
K.
, and
Hibi
,
T.
, 2001, “
Analysis of the Efficiency of a Half Toroidal CVT
,”
JSAE Rev.
0389-4304,
22
(
4
) pp.
565
570
.
10.
Tanaka
,
H.
, 2002, “
Speed Ratio Control of a Parallel Layout Double Cavity Half-Toroidal CVT for Four-Wheel Drive
,”
JSAE Rev.
0389-4304,
23
(
2
), pp.
213
217
.
11.
Osumi
,
T.
,
Ueda
,
K.
,
Nobumoto
,
H.
,
Sakaki
,
M.
, and
Fukuma
,
T.
, 2002, “
Transient Analysis of Geared Neutral Type Half-Toroidal CVT
,”
JSAE Rev.
0389-4304,
23
(
1
), pp.
49
53
.
12.
Newall
,
J.
, and
Lee
,
A.
, 2004, “
Measurement and Prediction of Spin Losses in the EHL Point Contacts of the Full Toroidal Variator
,” in Transient Processes in Tribology, proceedings of the 30th Leeds-Lyon Symposium on Tribology, LYON, September 2-5.
13.
Yamamoto
,
T.
,
Osidari
,
T.
, and
Nakano
,
M.
, 2002, “
Improvement of Loading Cam Performance in a Toroidal CVT
,”
JSAE Rev.
0389-4304,
23
(
4
), pp.
481
487
.
14.
Dowson
,
D.
,
Taylor
,
C. M.
, and
Xu
,
H.
, 1991, “
Elastohydrodynamic Lubrication of Elliptical Contacts with Spin and Rolling
,”
Proc. Inst. Mech. Eng., Part C: J. Mech. Eng. Sci.
0954-4062,
205
, pp.
170
174
.
15.
Tevaarwerk
,
J. L.
, and
Johnson
,
K. L.
, 1979, “
The Influence of Fluid Rheology on the Performance of Traction Drives
,”
ASME J. Lubr. Technol.
0022-2305,
101
, pp.
268
274
.
16.
Tevaarwerk
,
J. L.
, 1979, “
Traction Drive Performance Predictions for the Johnson and Tevaarwerk Traction Model
,” NASA Technical Paper No. 1530.
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