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3 - 4
Automatic 2-Speed Switching
Speed range changing is achieved by altering the angle of
the traction motor swash plate. A solenoid operated valve
routes pilot oil to the swash plate adjusting mechanism, as
appropriate, in response to range selection commands.
Low speed Operation
When ‘low speed’ is selected there is no pilot oil pressure at
port
D
. Spool
186
is pushed upwards by spring
189
and
pressure from port
A
or
B
. Oil is released from chamber
E
into the motor case via spool
186
and drain
H
, allowing
swash plate
103
to pivot on fulcrum
F
to the maximum angle
(O1) up against surface
Y
of spindle
2
. In this swash plate
position the piston stroke volume is maximised to produce
low speed revolution.
High Speed Operation
When ‘high speed’ is selected, pilot pressure greater than 39
bar (569 lbf/in
2
, 40 kgf/cm
2
) is applied to port
D
where it
overcomes the force of spring
189
and the pressure from
port
A
or
B
to push spool
186
down. The pressurised oil at
port
C
goes via spool
186
into chamber
G
and thence into
chamber
E
. Piston
161
pivots swash plate
103
about its
fulcrum
F
until it contacts surface
X
of spindle
2
. At this
minimum angle (O2) position, the piston stroke volume is
minimised to produce high speed revolution.
Section F
Transmission
9803/6410
Section F
3 - 4
Issue 1
Operation
JS01670
JS01680
Summary of Contents for JS130
Page 65: ...Section 3 Section 3 9803 6410 Issue 1 9 1 9 1 Routine Maintenance Component Location Diagram...
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Page 119: ...3 1 Section C Electrics 9803 6410 Section C 3 1 Issue 1 Layout Operator s Cab...
Page 142: ...5 3 Section C Electrics 9803 6410 Section C 5 3 Issue 1 Pump Control FLOW CHART...
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Page 210: ...3 4 Section E Hydraulics 9803 6410 Section E 3 4 Issue 2 Schematics Shuttle Block...
Page 532: ...Contents Page No Technical Data 1 1 i Engine 9803 6410 i Issue 1 Section K Section K...