Filter
Top Products
50
Power
Train
Tractors,
Lawn
and
Garden
- 110
and
112
10-2
Clutch,
Brake
and
Variable
Speed
Drive
SM-2059-{Apr-67)
VARIATOR
The
variator
(Fig.
4),
has
two
outside
half
sheaves
fixed
to
a
common
hub.
The
center
sheave
is
free
to
slide
on
the
shaft.
In
operation,
the
variator
is
moved
like
a
pendulum,
between
the
engine
drive
sheave
and
transmission
driven
sheave
(Fig.
5).
CLUTCH
POSITION
When
the
variator
is
moved
forward
to
the
"clutch"
pos
ition
(Fig.
5),
the
primary
be
It
ten-
sion
is
relieved
and
the
belt
is
forced
out
of
the
engine
drive
sheave
groove,
disengaging
the
drive.
SLOW
SPEED
POSITION
When
the
variator
is
moved
rearward
(Fig.
6),
the
primary
belt
tension
is
increased,
forcing
th
e
belt
into
the
e
ngine
drive
sheave
and
engaging
the
drive.
The
primary
belt
now
revolves
around
a
larger
radius
on
the
variator
while
the
second-
ary
belt
revolves
around
a
smaller
radius.
This
reduces
the
secondary
belt
speed
c
ausing
the
d
riven
sheave
on
the
transaxle
to
turn
slower.
This
results
in
a
slow
tractor
travel
speed
while
the
engine
speed
remains
constant.
HIGH
SPEED
POSITION
When
the
variator
is
moved
still
farther
to
the
rear
(Fig.
7),
the
primary
belt
is
forced
deep-
er
into
variator,
exerting
side
pressure
on
the
center
variator
sheave.
Because
the
center
sheave
is
free
to
slide
on
the
shaft,
the
pressure
exerted
by
the
side
of
the
primary
V-beltforces
the
center
sheave
towards
the
secondary
belt.
This
causes
the
secondary
belt
to
ride
up
the
sides
of
the
variator
and
revol
ve
around
a
larger
radius.
The
primary
belt
now
revolves
around
a
smaller
radius,
thereby
increasing
the
second-
ary
belt
speed
and
increasing
the
speed
of
the
transaxle
driven
sheave.
This
results
in
a
faster
tractor
travel
speed
while
the
engine
speed
remains
constant.
In
this
manner,
the
tractor
ground
speed
is
variable
in
all
transmission
gear
positions
and
at
any
engine
speed.
NOTE:
The
belts
change
position
in
the
variator
only
when
the
engine
is
'running.
fig.4-Voriator
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RY
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AR
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5-Cfutch
Position
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M 56
05
fig.
6-Slow
Speed
Position
S
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O
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ARY BELl
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ll
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M 56
06
fig.
7-High
Speed
Position
Litho
in
U.S.
A.