Saeco ODEA, Service Manual

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Page 8 / 14 Saeco Internationa Group
04 FUNCTIONAL PRINCIPLES TALEA / ODEA - LINE
Ceramic coffee grinder
The coffee grinder is driven by a direct current
motor (1) using a worm gear (2).
The worm (2) drives a plastic gear wheel (3)
where the lower ceramic disc (4) and the
copper pre-draw worm (5) is driven at the
bottom.
Two magnets (6) are built into the drive gear.
A Hall sensor is mounted on the bottom side
of the housing that sends 2 pulses to the
electronics using two magnets per rotation.
4.8. Coffee grinder
4.9. Dosing quantity control, coffee grinder blockage when machine is
low on beans
Low bean quantity
If the machine is low on beans, it is detected
from the speed difference (frequency Hall
sensor pulses) of the grinder between its idle
state and the bean grinding process.
If no beans are found in the grinder (idle
state), the speed and therefore the frequency
of the pulses is higher - small
t1 = “Beans low” message .
If beans are in the grinder, this results in a
reduced grinding speed due to the resistance
that is generated by the beans in the grinding
process and therefore, a greater
t2 = no message displayed .
t3 and t4 = This measurement is carried
out when the grinding process slows
down at the end.
Dosing quantity control
The dosing quantity is controlled using
the recorded pulses (number of rotations
proportional to the choose of aroma, mild,
medium and strong).
Coffee grinder blockage
If external objects enter the grinder, the
electronics detects the blockage from the missing
fl ow and stops the grinder.
with beans n=50%
without beans
n=50%
with beans
n=100%
without beans
n=100%
t
t
t
t
V
t4
t3
t2
t1
6
4
2
3
1