Necta Koro Espresso, Installation, Use And Maintenance Manual

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© by N&W GLOBAL VENDING SpA 0512 264 - 00
COFFEE UNIT OPERATION
COFFEE DISPENSING CYCLE
When confirming the switch on cycle of the machine, by
pressing a selection button, the coffee unit is rotated
completely before the normal cycle, to ensure that the
device is in the correct start position.
When making a coffee selection, the grinder will run for the
time necessary to fill the brewing chamber with the coffee
dose set via software.
When the ground coffee dose is reached, the ratiomotor
engaged with the handle (2) located outside the assembly
rotates by 180°, making the brew chamber swing and
lowering the upper piston (3) (see Fig. 16).
Due to the water pressure, the pre-brewing spring (7) sinks
and the lower piston (4) goes down 3 mm, thus forming a
water cushion which allows an even use of the coffee dose.
At the end of the dispensing cycle and during a pause of 3
seconds, the pre-brewing spring (7) will discharge the water
through the third way of the dispensing solenoid valve,
lightly pressing the used coffee dose.
By completing its rotation, the ratiomotor makes the swing-
ing lever (6) lift the pistons and the coffee dose.
At the same time, when the brewing chamber returns to its
vertical position, the scraper on the coffee hopper stops the
used coffee dose and drops it.
Pulled by the spring (5), the lower piston now returns to the
bottom dead centre.
Fig. 16
1 - Brewing chamber
2 - Handle
3 - Upper piston
4 - Lower piston
5 - Piston return spring
6 - Swinging lever
7 - Pre-brewing spring
Fig. 17
1 - Brewing chamber
2 - Handle
3 - Upper piston
4 - Lower piston
5 - Piston return spring
6 - Swinging lever
7 - Pre-brewing spring