OPTIMAL ADJUSTMENT OF THE PLUCKING SYSTEM
In order to get a good and quick result during the harvest, it is important that all parts
are adjusted perfectly to one another, in particular the plucking system, that ensure nice,
correct cut off fruits.
ADJUSTEMENT OF THE PLUCKING SYSTEM
The adjustment of the plucking system has to be done according to following pattern :
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Adjustment
Adjustment
Adjustment
Adjustment
Adjustment
of the detection field of the photo switch
of the speed of the plucking heads and the stem gripping rollers
of the first plucking pressure and T1
of the second plucking pressure and T2
start eject rollers T3
DETECTION FIELD PHOTO SWITCH
The detection of the present of a sprout
stick in the centring mechanism
happens by a photo switch (1). The
detection field (2) is the area from the
photo switch where the detection
happens. The detection field (2) can be
adjusted with the regulation nut above
the photo switch. The field must be
adjusted so that the detection happens
just a bit over the middle of the plucking
head opening.
The photo switch can also be rotated so
this one detects more or less to the
inside or to the outside. When turning
the photo switch to the outside the
plucking head will come into effect
faster because then it will take longer
before you will reach the knifes with the
stick, turning more to the inside gives
extra time to bring the plant into the
centring mechanism. However it is not
usual to adjust the operation like this. It
is better to adjust the times T1, T2, T3.
STEM GRIPPING ROLLERS
The faster the plucking head is turning, the more the arms of the knifes will be loaded by
the middle flying force. Because of this the arms are pulled to the outside and then the
closing pressure of the knifes is smaller. Therefore is the necessary to adjust first the
speed of the stem gripping rollers before you regulate the pressure.
The stem gripping rollers must be calibrated on a speed of 90 to 100 rotations per
minute while the engine is turning 1500 rotations per minute.
FIRST AND SECOND PLUCKING PRESSURE
The first pressure must be adjusted so that the knifes will cut just under the fruit; the
feet need to be short as possible. As starting pressure you can take 25 BAR, and so
adjust gradually. When the fruits themselves will be cut, then you need to increase the
pressure. When the fruits are being cut at the end of the stem then you need to increase
the second pressure. The maximum settable pressure is 40 BAR. When you still do not
get the required result, then you need to change to another type of knifes.
Standard value:
P1 :25 bar
P2 : 30 bar
TIME ADJUSTMENTS
Next to the pressure, the time is also important.
The time T1 gives you the time to bring the plant correctly in the machine via the
centring mechanism, before this will open and the first pressure will enter. Next the time
T2 needs to be regulated so that the second pressure that enters will run analogue with
the narrowing of the stem and the reducing of the sprouts. The time T3 that activates the
eject rollers may not start to early because this can snap off the stick.
Standard value:
T1: 0.2 sec
T2: 1.0 sec
T3: 1.5 sec
THE KNIFES
There are 9 kinds of knifes. The higher the number of the blade, the farther this will cut
on the stem, in other words the closer it will cut into the fruit.
The sprout harvesters are standard equipped with knifes with number 3. These have
approximately an angle of 30°.
However when you are still cutting with full pressure into the fruits, then there has to be
switched to a lower number of blade, so you receive the same result with a lower
pressure.
The opposite, when the sprouts have to much feet when the
pressure is very low, means switching on a higher number of
blade , that cuts farther from the stem.
+
The schedule on the right gives a survey of the existing
knifes.
In order to get an adjustment between the pressure
adjustment and the type of blade, the blade can be possibly
refined with an oilstone.
In order to let the knifes cut
farther from the stem, you
can whet the knifes on
the inside with an
oilstone.
Picture 1
Do you wish that the blade
stays a bit closer because
the sprouts are being
damaged it is advisable
to refine the outside of
the blade.
Picture 2
ALIGN
When the plucking head is turning the ends of the knifes must show one complete circle.
When there are two or more circles visible then one or more knifes are placed in the
wrong way. In this case the machine must be shut down.
By putting a bar in the input opening of the plucking head (between the knifes) you can
check which knifes are placed wrong. Never bent the knifes but adjust the arms of the
blade in order to get a circle.
In order to let the plucking head function as good as possible, this one needs to be
cleaned regularly. Always do this with a shut down engine.
When there is a noticeable margin on the entire plucking head or on the arms of the
knifes, this can be the result of wear on the bearings. In part IV you can find back how
you can dismantle a plucking head. In order to bring no damage to the plucking head,
bring it after the dismantlement to our company for revision. We advise you strongly not
to work on it by yourself.
Problem shooting
Problem
Engine will not start
Stick turns around in
plucking head
Can’t find the opening
Stick in torn off in the
plucking head
Cutted sprouts
Cause
Battery key ON
Emergency stops out
Main switch position 0
Direction fotoswitch not
correct
T1 too short
P1 too low
P1 too high
Speed plucking head
too high
T3 too short
P1 too low
T2 too long
Speed plucking head
too high
Blade broken off
Wrong type of blade
Sprouts have too much feet
P1 too high
Speed plucking head
too low
Wrong type of blade
Sprouts on the top are
cutted
T2 too long
P2 too low
Wrong type of blade
Sprouts on the leafs
T3 too short
P2 too high
Mounting of a boll
between the blades
Wrong type of blade
Speed and pressure of the
plucking head descends
Play on de blade arms
Sound from the head
bearing
Head stays closed
Head opens while plant is
moving through
V belt slips
Solution
Control of direction
T1 increase to max 0.5 sec
P1 increase to max 40 bar
P1 decrease to min 20 bar
Lower the speed to min 70
tr/min
T3 increase to max 5 sec
P1 increase to max 40 bar
T2 decrease to min T1
Decrease the speed to min 70
tr/min
Replace the blade
Mount other blades or fill the
blades
P1 decrease to min 20 bar
Increase the speed to max 110
tr/min
Mount other blades or fill the
blades
T2 decrease to min T1
Increase to max 40 bar
Mount other blades or fill the
blades
Increase to max 5 sec
P2 decrease to fully open
Mount other blades or fill the
blades
Check the V belt tension or if
necessary degraesing
Revision
Revision
Fotoswitch is dirty
Detection distance of
fotoswitch is wrong
Direction of the
fotoswitch is wrong
Clean the fotoswitch
Control of direction