Philips HD8841/09 - 3.4.2. Coffee Lack Detection and Grinder Blocked; 3.6.1. Bean Level, Dose, Grinder Blocked Logic

PHILIPS 4000 03 OPERATING LOGIC
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When the coee grinder is working, the soware monitors the current consumption. If the current value is
very low, the machine concludes that coee is missing; if the current value is very high, the machine concludes
that the coee grinder is blocked; instead, if the current value is in the middle, the machine concludes that all
is ok and it goes on to do the product.
Because the current consumption of grinder changes depending on the situations (motor new or old, cold or
hot, coee blends, etc.), these current targets are not static, but dynamic.
3.4.2. Coee lack detection and coee grinder blocked
3.5. Coee grinder 120V
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1
e coee grinder is driven by a direct current motor (1) using a worm screw helicoidal wheel transmission
(2). e worm screw (2) drives a plastic gear wheel (3), which turns the lower grinder (4) and the increment
pin (5) ere are two magnets (6) in the gear wheel; at every rotation these induce two pulses to a Hall sen-
sor, which in turn transmits them to the electronic system to grind the correct amount of coee.
3.6.1. Low bean level detection, dose quantity adjustment, coee grinder blocked
Without beans n=100%
With beans n=100%
Without beans n=50%
With beans n=50%
No coee
A low coee bean level is detected by the Hall sensor, aer
variations in the pulse frequency (with or without coee).
If there are no coee beans (operation while empty), the
number of rotations – and therefore the number of pulses –
will be greater.
t1 = no coee indication
If, however, there are coee beans, the number of rotations
will be lower due to the force created by the grinding.
t2 = no indication
t3 and t4 = this measurement is performed at the end of
each grinding process
Dose quantity adjustment
e dose quantity is adjusted in accordance with the pulses
detected (number of rotations proportional to the selected
avor – mild, medium or strong) and those established by
the soeware.
Coee grinder blockage
If the coee grinder becomes blocked for any reason, pulses
will no longer be transmitted to the electronic system and
the grinder will come to a stop.