2. Description of the machine
The excavator is made up of a front chassis section, a rear chassis section, a turntable, a cab and equipment
consisting of four elements.
2.1
Central joint
The ground contact of the four wheels is provided by the oscillation of the rear axle. The ground contact
of the four wheels is provided by the oscillation of the rear axle.
2.2
Stabilizers
Two independently-controlled stabilizers combined with the oscillation lock stabilize the machine during
operation.
2.3
Rear chassis
The rear chassis section is equipped with a water-cooled 4 in-line-cylinder engine.
- The engine drives two variable displacement pumps which perform the following functions:
• Transfer movement pump: coupled in a closed circuit with a variable displacement motor, the
assembly forming a hydrostatic transmission.
• Equipment pump: movements of the rams, power-assistance of the controls and associated
functions.
- The engine also drives a fixed displacement pump which performs the machine’s steering and slewing
movements.
2.4
Transmission
The transmission is of the permanent 4x4 type, with a limited-slip differential on both axles.
2.5
Turntable
The turntable is connected to the front chassis section by a slewing crown wheel. The turntable supports
the operator’s cab, the excavator’s equipment and the counterweight.
The slewing internal crown wheel is driven by a hydraulic motor equipped with a negative brake in the
event of a power-assistance pressure fault.
2.6
Cab
The monocoque cab is closed and heated. It is “FOPS” and “ROPS” approved (falling objects and roll-over
protective structure).
2.7
Controls
The cross position of the equipment controls makes it possible to combine the various actions flexibly and
efficiently.
2.8
Seat
The seat is sprung, dampened, height-adjustable and adjustable lengthwise.
2.9
Equipment
The equipment is in the centre of the machine. It is made up of four elements: the boom, the intermediate
boom, the coupling and the dipper.
The boom is controlled by the parallelogram formed by the boom ram, the braces and the boom
connecting rods. This gives it the advantage of a 140° travel.
The equipment can be offset on both sides by means of a hydraulic ram.
12MXT
28000
4
M1
Summary of Contents for 12 MXT
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