Gradall 544D-10 (9136-4142) Operation Manual - Manual (Page 23)

Form No. 20220 z z z z z 544D-10 Owner/Operator Manual
General
The brake system includes a service brake and a parking brake. Service and
parking brakes are applied through wet disc brake packs located within axle
housing.
Because service braking and “inching” (slow travel) functions overlap, some
features of inching will be discussed here. See “Drive Train” Section, Page
10.0, for additional information on inching travel. (See Figure 3-1 for layout
of controls)
Inching Travel
Overlap between braking and inching occurs because the same pedal controls
both functions; also because both functions control travel speed. However, the
methods of controlling travel speed are quite different. Service braking involves
a controlled stopping force applied to the front wheels. Inching involves a
controlled driving force applied to the driving wheels.
Figure 7-1
Most of the inching travel pedal stroke controls the speed of inching travel. As
the pedal nears the bottom of its stroke, service brakes are engaged.
Service Brakes
Depressing service brake/inching travel pedal to braking portion of pedal travel
causes controlled hydraulic pressure to be applied to service brakes. The greater
the pedal travel, the greater the braking force.
If power-assist fails, it will require much greater force on pedal to apply brake,
and stopping distance will be greater.
Parking Brakes
The parking brakes are spring-applied and hydraulically-released.
Hydraulic power to release parking brakes is provided by the hydraulic system
and is controlled by the parking brake switch located on the dashboard.
With the engine running and the parking brake switch “Off,” parking brakes
are disengaged. Moving the switch to “On” releases hydraulic pressure to apply
the parking brakes. With switch in “ON” position, four-wheel drive is disabled.
BRAKE SYSTEM 7.0
WARNING !
Practice inching/braking in a safe,
open area until you are thoroughly
familiar with handler response.
WARNING !
If power-assist feature should fail
for any reason, it would require
greater effort to apply service
brake. It is extremely important
that you never stop the engine
while traveling. If power assist
fails, stop as soon as possible. Do
not drive the handler until problem
has been corrected.
WARNING !
Always move parking brake switch
to “On” position before leaving cab.
Never stop engine while traveling.
Parking brake will be fully-applied
and unit may stop abruptly. A
sudden stop could cause load loss.
NOTE!
In the event of engine or hydraulic
failure, parking brakes can be
released for towing. See “To
Release Parking Brake,” Page
16.1.
SERVICE BRAKE/INCHING
TRAVEL PEDAL
HIGHEST INCHING TRAVEL SPEED
LOWEST INCHING TRAVEL SPEED
SERVICE BRAKING