Kalmar DCE80-100E, Technical Handbook

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DCE80-100E
Technical Handbook
Main hydraulics
Description
7 P. Group 70
TDCE01
04GB
Hydraulic system with separate side-lift hydraulics
Hydraulic diabram A44866.0100
The hydraulic system consists of the following sub-systems:
z Working hydraulics, machine, that include:
Servo hydraulics that supply pressure to the electro-hydraulic
servo system
– TILT
– LIFT
z Attachment hydraulics (see group 80)
– SIDESHIFT
– TWIST-LOCKS
– LENGTH ADJUSTMENT 20-40’
– LEVELLING
z Service brake system, WDB system
– Brake circuit, hydraulically controlled, oil-cooled plate
brakes
– Cooling circuit
z Parking brake system, disk brake on the drive axle's ingoing
shaft. Applied by spring pressure, released hydraulically.
z Steering system
Electro-hydraulic servo system, principles
The working hydraulics are controlled via an electro-hydraulic
servo system, the principle components of which are illustrated
on the next page.
All hydraulic system functions are controlled via three independ-
ent sub-systems:
– El-servo
– hydraulic-servo
– working hydraulics
The el-servo system is controlled by the ECU5 central computer
unit as part of the truck's ECS system. Descriptions of the servo
circuits can be found in separate publications.
From ECU5, digital or analogue signals are fed to the control le-
ver. The signals are affected by the degree of movement of the
control lever, after which they are fed back to and processed in
ECU5.
The out-signals for LIFT/LOWER and TILT INWARDS/OUT-
WARDS from ECU5 are fed to converters. The converters are
electrically controlled pressure reduction valves that convert the
electrical signal to a proportional hydraulic pressure - servo pres-
sure.
The side-lift is controlled in the same way.
The servo pressure affects the control slide in the main valve for
the function in question and from there, the main flow.
ECS-system, see separate publications