Eliminating Malfunctions - IKA MF 10 Mode D'emploi

Now the filter Pos. Z 1 that is suitable for the grinding pro-
cedure can be inserted; to do so the filter is pushed into the
grinding chamber from the front. The filter and the filter
holder surface in the grinding chamber must be free from
dirt and dust.
Now the grinding chamber door can be closed and locked
with the operating knob Pos. P 10. The screw mounting of
the operating knob is screwed in by pressing and twisting
it into the internal thread on the drive cover. The first turns
are easy, if turning becomes difficult then the door may be
closed, but the safety switch is not yet unlocked. Continue
turning until stop (approximately two revolutions), only then
is the safety switch unlocked and the mill ready to start.
Grinding operation with impact grinding mill:
The suitable filter is pushed in and the door is locked before
beginning the grinding procedure.
Afterwards a collecting pan is fastened to the discharge
cone (standard ground joint NS 29). Suitable containers are
e.g. Erlenmeyer flasks Pos. Z 3, round-bottomed flasks, test
tubes made of either glass or plastic. The containers are to
be secured with a fixing clip Pos. Z 2 (see fig. 1).
For heat sensitive materials or with ground materials that
have a very high increase in volume during cut up, it is ad-
visable to use a erlenmeyer flasks with a filter attached to
its second (e.g. cotton wool, etc...). The ground material is
cooled from the air flow and no excess pressure is created.
For very critical ground materials (very fine powder after be-
ing cut up) the ground material can also be sucked off by
means of a commercial vacuum cleaner with a suction tube
adapted at the discharge cone. The powder is then in the
vacuum cleaner bag where it can be removed for further
processing steps.
The ground material which has prepared to the correct feed
grain size is filled into the funnel and then the cover Pos. P 17
is applied. The speed knob Pos. A 12 is turned to the left stop
(3000 rpm).
The mill is started by shifting the rocker switch Pos. A 13
to Position 1. First the green „Power" LED is lit and then
„Overload" LED lights up briefly before the motor smoothly
starts. The speed can be set by turning the speed knob to
the desired speed. A speed of more than 4500 rpm is rec-
ommended for impact grinding.
Now the ground material can be metered by turning the
dosing sluice Pos.P6 in a clockwise direction. You can hear if
ground materials gets into the grinding chamber and if too
much materials has been metered then the rotor speed de-
creases. This drop in speed is clearly indicated by the lower
grinding noises and the orange „Overload" LED lights up.
Metering of the ground material should only be resumed
when the speed has returned to the adjusted value or if the
„Overload"-LED is no longer lit.
If this is done then the mill becomes overloaded and switch-
es off after some time because of overheating. This is then
indicated by the red „Error" LED. In addition, a beep sounds
to indicate that the mill should be switched off using the
rocker switch Pos. A 13. The mill must then cool off for
a period in order to be able to start in again (see chapter

"Eliminating malfunctions").

In addition, the ground material is no longer cut up the low-
er speed when the unit is operated with an overload because
the impact energy no longer suffices for breaking the ground
material. Keeping the ground material in the grinding cham-
ber and the ground material to heat up. In extreme cases
this can result in the ground material caking on the grinding
chamber parts which then entails a time-consuming clean-
ing operation.
If the funnel is empty then the mill remains turned until all
of the ground material from the grinding chamber is in the
container. This is the case if cutting up noises can no longer
be heard.
When it comes to cleaning the grinding chamber experi-
ence has shown that it makes sense to briefly switch the
unit to maximum speed after the grinding operation has
been completed and only then to turn the speed knob to
the left stop. The mill is then shut off with the switch.
The filter is removed after opening the grinding chamber
door and any remaining ground material is wiped into the
collecting pan.
Attention! After longer grinding cycles the grinding cham-
ber and the filters may have an increased temperature. Pro-
tective personal equipment should be worn in this case.
It may help to crush the ground material in several steps, i.e.
a filter with large perforations is used for pre-crushing and
finer ones in each of the following steps. (see fig. 4).
Advantages:
• Fewer failures, e.g. due to clogged filters or overloading
the motor.
• Less heat-up of ground material since the retention time
of the ground material in the grinding chamber is sub-
stantially reduced.
• Closer grain size spectrum for the final material.
• Normally less total grinding with better results as despite
several runs comminution is performed more quickly and
more effectively.
Disassembling the impact grinding head:
Before disassembling the head of the mill, the mill itself
must first cool down as the grinding chamber and the beat-
er rotor cannot detached otherwise.
The power supply plug must be disconnected before disassem-
bly. After opening the door, the countersunk screw, P 15, is
loosened using an Allen key, while the rotor is held by the face
spanner that is included in delivery. The spanner is positioned
so that the pins of the spanner are inserted into the bore holes
on the face of the rotor. The disc must be turned so that the
bore hole in the rotor is accessible for the spanner pins.
If the hexagon socket is dirty then it must be cleaned by
means of a brush. After the countersunk screw and the
disc, P 11, have been removed the hammer rotor, P 13, is
removed. The adjustment spring must be in the area of the
opening (in the back wall of the mill chamber). Now the three
screw mountings Pos. P5 are loosened by means of a fork
wrench and the grinding chamber is rotated in a clockwise
direction and taken off.
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