Haulotte HA 41 PX, Operating And Maintenance Instructions Manual

Page: 29 / 82

Operation and Maintenance
17
3 -
OPERATING PRINCIPLES
3.1 - HYDRAULIC SYSTEM
All the movements of the machine are ensured by the hydraulic power
provided by a power pack.
3.1.1 - Lateral movement
3.1.1.1 -Lateral (displacement of the machine)
The lateral movement is fed by a hydraulic pump with closed loop, variable
flow and electric drive.
Four hydraulic motors with two cylinders mounted in the wheels ensure the
drive of the wheels via dampeners
The break release is automatic with electric drive. As soon as movement
stops, the brake springs back into position.
The two speeds (high or low) are controlled by a switch. .
The control handle proportionally controls the cubic capacity of the transfer
pump.
The four motors are supplied in parallel.
There is hydraulic differential gearing on each axle. They each receive a
quarter of the pump throughflow.
3.1.1.2 -Equipment
The movement of the equipment are ensured by an open circuit hydraulic
pump with 'LOAD SENSING' regulation.
3.1.2 - Movements for telescoping, orientation, lifting of
the arm and raising of the fly jib
are carried out through proportional distribution compensated by pressure.
The flow of the pump changes automatically on request through "LOAD
SENSING" drains. In neutral, there is no flow from the pump.
3.1.3 - Movements for raising the suspension platform,
platform rotation, platform compensation and
direction
are controlled by 4 way electro-valves, with all or zero flow. A slide-valve
in the proportional distributor provides the flow necessary to these
movements.
3.1.4 - The telescoping jacks for raising the fly jib, and
lifting the arm and suspension platform
are equipped with watertight sealed safety valves.
Low transfer speed Top speed of traverse
The four motors have a large cubic capacity.. The four motors are controlled by an electro-valve with
low cubic capacity.