Infinitely Variable Transmission Utilizing Oscillating Torque
William Terry Lester
Lestran Engineering
Fort Worth, Texas, USA
Abstract
A unique infinitely variable transmission utilizing
oscillating torque to transmit mechanical power will
be presented. Modeling of the dynamics for an
automotive application will demonstrate its high
performance characteristics. Analysis indicates
that the upper design load limit is nearly unlimited
and mechanical efficiency exceeds 98% for most
operational conditions, due to pure dynamic
coupling and the small number of energydissipating components.
The control system
requires only minimal electrical components that
integrate easily with internal combustion engines.
Introduction
Unlike conventional transmissions, this infinitely
variable transmission (IVT) controls the output
torque as opposed to the output speed ratio (Fig.
1). Infinitely variable torque, from zero torque to
the full capability of torque output, can be produced
with no clutching or torque conversion required at
the input. The power from the centrifugal forces of
eccentric rotating masses is harnessed to create an
oscillating torque. One-way clutches convert the
oscillating torque to a unidirectional torque.
Variable control of the amplitude of the torque
results from the change in the center of gravity of
the rotating masses.
pair of eccentric masses, rotatably coupled thereto.
An input shaft driven by the engine rotates the
eccentric masses about the ends of the arm
assembly, causing the rotating masses to produce
an oscillating torque to the arm assembly.
The arm assembly is coupled to an output
assembly that uses two one-way clutches, with one
clutch reversed relative to the other. Unique oneway clutches, developed and manufactured by KerTrain Research Inc. of Kingston, Ontario, Canada,
convert the bidirectional torque of the arms to
unidirectional torque. These one-way clutches
allow rotation in one direction. Reverse motion is
accomplished by reversing the action of the oneway clutches.
Variation of the phase of the eccentric masses is
achieved by means of a rotary actuator. The
changes of phase alter the center of gravity of the
masses, thus controlling the amplitude of the torque
applied to the arm assembly and the output speed
to the load.
Components
The transmission consists of an Input Assembly,
Arm Assembly and Output Assembly (Fig. 2). The
components are grouped as follows:
Input Assembly
Fig. 1 - IVT
Function: produces the variable oscillating
torque
Elements: (1.) input shaft, (2.) rotary actuator,
(3.) bearing mount, (4.) outer drive
yoke, (5.) inner drive yoke, (6.) links,
(7.) rotatable mass bearings, (8.)
rotatable masses, (9.) hubs
An arm assembly is rotatably coupled to a casing.
Positioned at each end of the arm assembly is a
The input shaft is the input member that is rotated
by an engine (rotational power source). The input
shaft, rotary actuator, and outer drive yoke are
directly coupled and rotate together. The rotary
actuator controls the angular position of the inner
drive yoke relative to the outer drive yoke.
1 Input Shaft
2 Rotary Actuator
3 Bearing Mount
4 Outer Drive Yoke
5 Inner Drive Yoke
6 Links
7 Rotatable Mass Bearings
8 Rotatable Masses
9 Hubs
10 Alignment Bearing
11 Shafts
12 Mounting Tube
13 Casing
14 Alignment Bearings
15 Slip Ring
16 One-Way Clutches
17 Output Shaft
Input Assembly
6
7
8
5
9
8
8
2
4
7
6
1
9
3
10
11
8
12
Arm Assembly
Output Assembly
11
13
14
14
15
16
17
16
Fig. 2 - IVT Components
The inner and outer drive yokes transmit the input
torque through the links to the rotatable masses.
The rotary actuator, combined with the inner and
outer drive yokes, furnishes the variable control of
the phase of the rotatable masses. The rotary
actuator ranges from 0 to 180 degrees.
The one-way clutches, functioning in directions
reversed from one another, convert the oscillating
torque to a unidirectional torque. The first one-way
clutch connects the arm assembly to the casing;
the second one-way clutch connects the arm
assembly to the output shaft.
Several types of rotary actuator devices are
available for this transmission. The computercontrolled actuator relies on inputs from engine
speed and throttle position.
The internal
components of the rotary actuator are not shown in
the figures.
The output shaft relays the resultant power to the
transportation application.
The rotatable masses are two pairs of side-by-side
eccentric masses. Roller bearings placed inside
the hubs of the rotatable masses facilitate rotation
of the masses about the shafts of the arm
assembly. As the masses rotate about the arm
assembly, centrifugal forces generate oscillating
torque.
Arm Assembly
Function: supplies the structural interface
between the input and output
assemblies
Elements: (10.) alignment bearing, (11.) shafts
(12.), mounting tube
The arm assembly resembles a crankshaft and
operates as the interface between the input and
output assemblies.
Rotatably coupled to the
casing, the shafts support the rotatable masses.
The moment arm for the output torque is the offset
distance of the shafts, called the Arm Assembly
Radius.
The alignment bearings support the rotating
components within the casings. The slip ring
provides the electrical interface to the rotary
actuator.
Mechanics
The IVT utilizes an oscillating torque to vary the
mechanical power transmitted to a load. The arm
assembly is rotatably coupled to the casing.
Rotatably coupled to the shafts of the arm
assembly are the rotatable masses, two pairs of
side-by-side eccentric masses. The input shaft
rotates the masses about the shafts of the arm
assembly. The centrifugal forces from the rotating
masses produce an oscillating torque that causes
the arm assembly to oscillate.
The inner and outer drive yokes and the links
provide the means to transmit the input torque to
the rotatable masses (Fig. 3). This mechanism
resembles a four bar linkage.
Rotatable Mass
Link
Drive Yoke
The mounting tube attached to the shafts functions
as the coupling component for the one-way
clutches to the output assembly.
Output Assembly
Function: converts the oscillating torque to a
unidirectional torque
Elements: (13.)
casing,
(14.)
alignment
bearings, (15.) slip ring, (16.) oneway clutches, (17.) output shaft
The output assembly comprises a casing that acts
as a stationary support structure for the assembled
transmission and incorporates two one-way
clutches and an output shaft.
Fig. 3 – Rotating the Rotatable Masses
The arm assembly is coupled to an output
assembly. The output assembly employs one-way
clutches, with one clutch reversed relative to the
other clutch, to convert the bidirectional torque of
the arm assembly to a unidirectional rotation for the
output load.
In a cyclic process, the torque oscillates from a
clockwise to a counter-clockwise direction as the
eccentric masses rotate about the shafts of the arm
assembly. The one-way clutches engage and
disengage, conforming to four stages of the
process (Fig. 4). The cyclic process is described
below.
Centrifugal Force
Rotatable Mass
Arm Assembly
Stage 3


the one-way clutch to the output shaft is
disengaged
zero torque
Process from Stage 3 to Stage 4 (Process 3-4)
 counter-clockwise torque is applied to
the arm assembly
 arm assembly decelerates
Stage 4


the one-way clutch to the casing is
engaged
rotational velocity of arm assembly is
zero
Process from Stage 4 to Stage 1 (Process 4-1)
 counter-clockwise torque is applied to
the casing
Stage 1
Stage 2
Stage 3
Stage 4
Zero Torque Clockw ise Torque Zero Torque Counter-Clockw ise Torque
Fig. 4 – Four Stages of the Cyclic Process
(The arm assembly radius is exaggerated in the illustration.)
Cyclic Process
Stage 1



the one-way clutch to the casing is
disengaged
zero torque
zero rotational velocity of the arm
assembly
Variable control is achieved by changing the
amplitude of the centrifugal forces produced by the
rotatable masses. The masses are paired so that
their phases range from 0° in phase for maximum
torque to 180 out of phase for zero torque or any
intermediate setting.
The output amplitude of the oscillating torque is
dependent on the phase of the rotatable masses.
The phase changes the center of gravity of the
masses, thereby controlling the torque applied to
the arm assembly (Fig. 5).
The computercontrolled actuator attached to the input shaft
regulates the phase.
Center of Gravity
Rotatable Masses
Process from Stage 1 to Stage 2 (Process 1-2)
 clockwise torque is applied to the arm
assembly
 arm assembly accelerates
Stage 2


the one-way clutch to the output
component is engaged
rotational velocity of the arm assembly
and the output shaft are equal
Process from Stage 2 to Stage 3 (Process 2-3)
 clockwise torque is transmitted to the
output shaft via the arm assembly
In Phase
Maximum Torque
90° Out of Phase
Intermediate Torque
180° Out of Phase
Zero Torque
Fig. 5 – Phase Angle Controls Output Torque
Amplitude
Reverse motion is carried out by reversing the
action of the one-way clutches. The capability
to switch the action of the clutches is provided
by the revolutionary clutch developed and
manufactured by Ker-Train Research Inc., of
Kingston, Ontario (U.S. Patent 6,409,001).
This clutch has a load capacity five times
greater than a sprag-type clutch, with an
indexing rate of up to 100 Hz. This indexing
rate would allow the IVT to operate at engine
input speeds of up to 6000 rpm. (The indexing
rate is the number of load cycles that the clutch
engages and disengages per second.)
Although the IVT rapidly engages and disengages
the one-way clutches, the clutches do not
experience impact or shock loads due to the fact
Table 1 – Maximum Output Torque
The product of the centrifugal force of the rotatable masses
(Table 2) and the arm assembly radius is illustrated.
Phase
Angle
Automotive Application
The transmission design presented herein is sized
to demonstrate the transmission’s capabilities in an
automotive application. The cylindrically-shaped
casing measures 75 cm in length and 25 cm in
diameter. The IVT mass is estimated to be less
than 70 kg. The data presented in the following
sections pertain to this automotive application.
Performance
Performance characteristics depend on the input
and output speeds (Figs. 6, 7, 8 and 9). The power
and average output torque increase as input and
output speeds increase, with the output speed
being less than or equal to the input speed.
Alterations of the phase angle of the rotatable
masses maintain optimum engine speed as the
vehicle accelerates.
The Dynamics Characteristics (Figs. 10, 11, 12, 13,
14 and 15) result from the cyclic process in which
power is transmitted:
Stage 3
Stage 4
degree
cm
0.0
64.4
92.3
114.8
134.8
153.3
6.5
5.5
4.5
3.5
2.5
1.5
Maximum Output Torque
N-m
Input
Speed
1000
rpm
97
82
67
52
37
22
Input
Speed
2000
rpm
388
328
268
209
149
89
Input
Speed
3000
rpm
872
738
604
470
336
201
Input
Speed
4000
rpm
1551
1312
1074
835
597
358
Table 2 – Rotatable Mass Centrifugal Force
One of this IVT’s strengths is its ability to produce
high output torque, as exhibited in Tables 1, 2 and
3.
Stage 1
Stage 2
Radius to
C.G. of
Rotatable
Masses
The process begins.
The arm assembly speed matches
the output speed.
The arm assembly begins to
decelerate.
The arm assembly reaches zero
velocity.
The output torque resembles the performance
characteristics of a two-piston internal combustion
engine. The arm assembly transmits torque to the
one-way clutches, which then distribute the torque
to the output shaft and to the casing.
The
maximum magnitude of the reaction torque to the
casing and the output shaft are equal.
The product of the rotatable masses and their centrifugal
acceleration (Table 3) is illustrated.
Phase
Angle
Radius to
C.G. of
Rotatable
Masses
degree
cm
0.0
64.4
92.3
114.8
134.8
153.3
6.5
5.5
4.5
3.5
2.5
1.5
Rotatable Mass
Centrifugal Force
N
Input
Speed
1000
rpm
9700
8200
6700
5200
3700
2200
Input
Speed
2000
rpm
38800
32800
26900
20900
14900
8900
Input
Speed
3000
rpm
87200
73800
60400
47000
33600
20100
Input
Speed
4000
rpm
155100
131200
107400
83500
59700
35800
Table 3 – Rotatable Mass Centrifugal Acceleration
The magnitude of the centrifugal acceleration is a function of the
input speed and the radius to the center of gravity of the rotatable
masses from the center of the arm assembly shafts. The radius
varies from 6.5 cm for 0° phase angle to 0.0 cm for 180° phase
angle. The arm assembly radius and the total mass of the
rotatable components amount to 1.0 cm and 13.6 kg, respectively.
Phase
Angle
Radius to
C.G. of
Rotatable
Masses
degree
cm
0.0
64.4
92.3
114.8
134.8
153.3
6.5
5.5
4.5
3.5
2.5
1.5
Rotatable Mass
Centrifugal Acceleration
m/sec2
Input
Speed
1000
rpm
713
603
493
384
274
164
Input
Speed
2000
rpm
2851
2413
1974
1535
1097
658
Input
Speed
3000
rpm
6415
5428
4441
3454
2467
1480
Input
Speed
4000
rpm
11405
9650
7896
6141
4386
2632
0.0°
114.8°
6
64.4°
134.8°
Average Output
Torque (N-m)
Power (kw)
8
92.3°
153.3°
4
2
0
0
200
400
600
800
Output Speed (rpm)
(a)
80
0.0°
114.8°
60
64.4°
134.8°
92.3°
153.3°
40
20
0
1000
0
200
400
600
800
Output Speed (rpm)
(b)
1000
60
50
40
30
20
10
0
0.0°
114.8°
0
64.4°
134.8°
Average Output
Torque (N-m)
Power (kw)
Fig. 6 – Performance Characteristics for 1000 rpm Input Speed (Legend: Phase Angle of Rotatable Masses)
92.3°
153.3°
500
1000
1500
Output Speed (rpm)
(a)
300
250
200
150
100
50
0
0.0°
114.8°
2000
0
64.4°
134.8°
92.3°
153.3°
500
1000
1500
Output Speed (rpm)
(b)
2000
Power (kw)
200
0.0°
114.8°
150
64.4°
134.8°
Average Output
Torque (N-m)
Fig. 7 – Performance Characteristics for 2000 rpm Input Speed (Legend: Phase Angle of Rotatable Masses)
92.3°
153.3°
100
50
0
0
1000
2000
Output Speed (rpm)
(a)
3000
750
0.0°
114.8°
600
64.4°
134.8°
92.3°
153.3°
450
300
150
0
0
1000
2000
Output Speed (rpm)
(b)
3000
Power (kw)
500
0.0°
114.8°
400
64.4°
134.8°
Average Output
Torque (N-m)
Fig. 8 – Performance Characteristics for 3000 rpm Input Speed (Legend: Phase Angle of Rotatable Masses)
92.3°
153.3°
300
200
100
0
0
1000
2000
3000
Output Speed (rpm)
(a)
4000
1250
0.0°
114.8°
1000
64.4°
134.8°
92.3°
153.3°
750
500
250
0
0
1000
2000
3000
Output Speed (rpm)
(b)
4000
Fig. 9 – Performance Characteristics for 4000 rpm Input Speed (Legend: Phase Angle of Rotatable Masses)
Arm Speed (rpm)
Arm Position (degree)
75
50
25
0
0.00
0.05
0.10
Time (sec)
(a)
0.15
0.20
75
50
25
0.00
150
100
50
0.05
0.10
Time (sec)
(c)
0.05
0.10
0.15
0.20
0.15
0.20
Time (sec)
(b)
Output Torque (N-m)
Input Torque (N-m)
100
0
200
0
0.00
125
0.15
400
350
300
250
200
150
100
50
0
0.00
0.20
0.05
0.10
Time (sec)
(d)
300
Arm Speed (rpm)
Arm Position (degree)
Fig. 10 – Dynamics Characteristics, 2000 rpm Input Speed, 100 rpm Output Speed, 0.0° Phase Angle
250
200
150
100
50
0
0.00
0.10
Time (sec)
(a)
0.15
0.20
300
200
100
0.00
250
200
150
100
50
0.05
0.10
Time (sec)
(c)
0.05
0.10
0.15
0.20
0.15
0.20
Time (sec)
(b)
Output Torque (N-m)
Input Torque (N-m)
400
0
0.05
300
0
0.00
500
0.15
0.20
400
350
300
250
200
150
100
50
0
0.00
0.05
0.10
Time (sec)
(d)
Fig. 11 – Dynamics Characteristics, 2000 rpm Input Speed, 400 rpm Output Speed, 0.0° Phase Angle
Arm Speed (rpm)
Arm Position (degree)
600
500
400
300
200
100
0
0.00
1000
800
600
400
200
0
0.05
0.10
0.15
0.20
0.00
0.05
Time (sec)
(a)
Output Torque (N-m)
Input Torque (N-m)
400
300
200
100
0
0.00
0.05
0.10
Time (sec)
(c)
0.10
0.15
0.20
0.15
0.20
Time (sec)
(b)
0.15
400
350
300
250
200
150
100
50
0
0.00
0.20
0.05
0.10
Time (sec)
(d)
1200
Arm Speed (rpm)
Arm Position (degree)
Fig. 12 – Dynamics Characteristics, 2000 rpm Input Speed, 800 rpm Output Speed, 0.0° Phase Angle
800
400
0
0.00
0.05
0.10
0.15
1400
1200
1000
800
600
400
200
0
0.20
0.00
0.05
Time (sec)
(a)
Output Torque (N-m)
Input Torque (N-m)
500
400
300
200
100
0
0.00
0.05
0.10
Time (sec)
(c)
0.10
0.15
0.20
0.15
0.20
Time (sec)
(b)
0.15
0.20
400
350
300
250
200
150
100
50
0
0.00
0.05
0.10
Time (sec)
(d)
Fig. 13 – Dynamics Characteristics, 2000 rpm Input Speed, 1200 rpm Output Speed, 0.0° Phase Angle
Arm Speed (rpm)
Arm Position (degree)
1600
1200
800
400
0
0.00
2000
1500
1000
500
0
0.05
0.10
0.15
0.20
0.00
0.05
Time (sec)
(a)
Output Torque (N-m)
Input Torque (N-m)
600
500
400
300
200
100
0
0.00
0.05
0.10
0.15
Time (sec)
(c)
0.10
0.15
0.20
0.15
0.20
Time (sec)
(b)
400
350
300
250
200
150
100
50
0
0.00
0.20
0.05
0.10
Time (sec)
(d)
4000
Arm Speed (rpm)
Arm Position (degree)
Fig. 14 – Dynamics Characteristics, 2000 rpm Input Speed, 1600 rpm Output Speed, 0.0° Phase Angle
3000
2000
1000
0
0.00
2000
1500
1000
500
0
0.10
0.20
0.30
0.00
Time (sec)
(a)
Output Torque (N-m)
Input Torque (N-m)
500
400
300
200
100
0.10
Time (sec)
(c)
0.20
0.20
0.30
Time (sec)
(b)
600
0
0.00
0.10
0.30
400
350
300
250
200
150
100
50
0
0.00
0.10
0.20
Time (sec)
(d)
0.30
Fig. 15 – Dynamics Characteristics, 2000 rpm Input Speed, 1900 rpm Output Speed, 0.0° Phase Angle
that there is no instantaneous change in velocity.
The driver (arm assembly) and driven members
(casing and output shaft) rotate at the same
velocity when the one-way clutches are engaged
(Stages 2 and 4).
Mechanical Efficiency
In addition to the transmission’s ability to match
continuously the optimum engine speed to any
vehicle speed, the small number of energydissipating components yields a high mechanical
efficiency that exceeds 98% for most operational
conditions. The energy losses are attributable to
the rotatable mass bearings, the rotary actuator
and the one-way clutches. The primary power loss
emanates from the bearings for the rotatable
masses. Power losses from the rotary actuator and
one-way clutches are negligible.
Endurance
The compact design and small number of
components enable the IVT to be manufactured for
long service life, primarily by selecting rugged and
efficient one-way clutches and the rotatable mass
bearings.
Ker-Train Research Inc. of Kingston, Ontario,
Canada offers a one-way clutch for low Hertz
stresses which measures 3.8 cm in length and
12.8 cm in outer diameter and has a maximum
torque rating of 10000 N-m. The IVT’s
maximum output torque of 1551 N-m (Table 3)
would merely consume 1/8 of the torque rating
for this one-way clutch, translating into a
transmission service life that will exceed the
vehicle’s life. (Fig. 16)
Bearing power losses are the product of the input
speed in radians per second and the bearing
friction torque. Equation 1 governs the bearing
friction torque (Mfriction). The input speed, as shown
in Table 4, affects the magnitude of these losses.
The centrifugal force from the rotatable masses
produces the load on the bearing (F).
The
percentage of the power loss from the bearings
results from the power transmitted by the IVT, and
is small for any significant power transmission.
Mfriction = f F dm
Equation 1
coefficient of friction (f) = 0.0003
bearing pitch diameter (dm) = 7.9 cm
Incremental usage of the rotary actuator combined
with its maximum power rating of 0.20 kw produces
a minimal power loss projection of less than 0.02
kw. Maximum power is not required for most of the
changes in the phase angle of the rotatable
masses. The resulting incremental usage of the
actuator is estimated to be less than 10%.
Tests conducted by Ker-Train Research Inc.
conclude that the power losses for the one-way
clutches should amount to less than a fraction of
one percent.
Table 4 – Bearings Power Losses
Input Applied
Bearing
Bearing
Speed
Load
Friction Torque Power Loss
rpm
N
N-m
kw
1000
9700
0.229
0.023
2000
38800
0.916
0.192
3000
87300
2.062
0.648
4000 155200
3.666
1.536
Fig. 16 – One-Way Clutch
The service life for the rotatable mass bearings
is determined by the input speed and the
applied load, presented in percentage of
bearing life and time in Table 5. For this
design eight Torrington spherical roller
bearings (22211CJ) are used, with a dynamic
loading of 120000 N per bearing and
dimensions of 5.5 cm bore diameter, 10.0 cm
outer diameter and 2.5 cm width.
Table 5 – Rotatable Mass Bearing Life
Input Applied
Service
Service
Speed
Load
Life
Life
rpm
N
Percentage Hours
1000
9700
0.3
200000
2000
38800
8.6
30000
3000
87300
63.0
10000
4000 155200
28.2
500
Development History and Status
While in graduate school, I read an article about the
importance and advantages of CVTs. My interest
in CVTs was piqued by a statement in the article
that it is physically impossible to engineer a CVT
that is practical for high power applications. I took
on this issue as a personal challenge and began a
twenty-three year quest to develop a high torque
CVT. In the mid-nineties, I recognized that the
centrifugal force from a rotating mass generates
high torque, spurring me to pursue the
development of a new class of IVT. During the
development process extensive kinematic analyses
were performed, several working models were
constructed, and patents were issued (U.S. Patents
6,044,718 and 6,062,096).
A model (Fig. 17 and 18) was installed in a go-kart
to demonstrate my concept. The transmission
supplied smooth acceleration and high torque. Two
large men attempted to hold back the go-kart from
1
2
3
4
5
6
7
an idling position as the driver depressed the
accelerator, but were unable to do so. This model
had only one pair of rotatable masses; therefore,
the center of gravity of the rotatable masses did not
change in this model.
It performed like a
mechanical torque converter. Also, gears were
used to transfer torque to the rotatable masses.
Subsequently, a second go-kart model (Fig. 19)
was constructed with the improved simpler design
to transmit the input torque to the rotatable masses
by means of the drive yoke and links, yielding a
smoother performance.
The IVT presented herein is being developed for a
full-sized automotive application.
In the
development process a desktop model is being
designed to demonstrate the computer control
system in a controlled environment.
After
verification of the control system is completed, the
IVT will be constructed and tested in a full-sized
vehicle.
Input Shaft
Timing Gears
Rotatable Masses
Arm Assembly
Frame
Output Shaft
One-Way Clutches
3
7
1
2
3
4
6
5
Fig. 17 – Test Model Components
but would result in a 70% reduction in overall
performance.
Fig. 18 – Test Model Installed in Go-Kart
Fig. 20 – Constantinesco CVT
The process of power transmission presents
another difference between the Lester IVT and
previous designs.
The inertia reaction loads
applied to the differential lever provides the variable
transmission of power in the Constantinesco CVT.
The differential lever functions as a gear that
supplies the interface for the input from the crank
shaft, the reaction loads from the inertia wheel, and
the output to the drive shaft. Conversely, the
centrifugal force from the rotatable masses directly
transmits power in the Lester IVT.
Fig. 19 – Improved Go-Kart Model
Conclusion
Prior Art
This unique IVT design harnesses the power from
the centrifugal force of a rotating mass. High
torque is smoothly generated from the centrifugal
force of a small mass. This design satisfies the
torque, size, mass and endurance requirements for
all transportation applications. Additionally, the
small number of energy-dissipating components
provides a high mechanical efficiency under all
driving conditions and keeps manufacturing costs
low. In addition, exotic materials are not required.
Previous CVTs, including the Belt, toroidal, and
Constantinesco, control the speed ratio. Their
output torque is the product of the input torque and
the speed ratio.
In contrast, the Lester IVT
operates as an infinitely variable mechanical torque
converter. It controls the magnitude of the output
torque instead of the speed ratio.
Similarly, the Constantinesco CVT (Fig. 20) and the
Lester IVT apply a ratcheting or one-way clutching
device to convert an oscillating torque into a
unidirectional torque. Also, they both utilize an
inertial reaction force to achieve variable control.
However, both of the one-way clutches transmit
power for the Constantinesco CVT, while the
one-way clutch that is constrained to the casing
does not transmit power in the Lester IVT.
Incorporating the Constantinesco CVT’s ratcheting
methodology in the Lester IVT would be possible,
This rugged and economical IVT can easily be
engineered for even a semi-truck application (Table
6).
Table 6 – Semi-Truck IVT Specifications
Length
125 cm
Diameter
50 cm
Maximum Output Torque
10000 N-m
Mass
150 kg
Input Speed
2000 rpm
Endurance Life for continuous 50000 hours
operation at maximum torque.
References
1. Tedric A. Harris, “Rolling Bearing Analysis,
Third Edition,” Wiley-Interscience Publication,
dated 1991, pages 149 and 504-511.
2. “The Torrington Company Service Catalog,”
dated 1991, pages 244 and E54-E57.
3. George Constantinesco: Inertial Transmission,
http://www.rexresearch.com/constran/1constran.htm
Contacts
1. William Terry Lester
4008 Shannon Dr.
Fort Worth, Texas 76116
Phone:
817.735.1824
E-mail:
wmterrylester@aol.com
2. Mitch Kerr
Ker-Train Research Inc.
Kingston, Ontario, Canada
Phone:
613.531.3155 Ex 100
E-mail:
mitch@kertrain.com