ROSTA
2.23
Oscillating Mountings
conveying direction
Technology
3. One mass shaker conveyor systems: Installation instructions
4. Average material speed on shakers v
m
Main influence factors
– layer height of material
– property trough bottom (slip-
resistance)
– mounting angle
β
of the rockers
– feeding capability of the material
depending on size, form and hu-
midity of the grains, e.g. very dry
and fine grained material is submit-
ted to slippage factors up to 30 %.
Example: One mass system
with eccentric drive
Out of the intersection point
R = 12 mm
and the revolutions
n
s
= 340 min
-1
is resulting a
theoretical material speed of
v
m
= 12 m/min
or
20 cm/sec.
By acceleration factors
K > 2
and
rocker mounting angles of
β
= 30°
(to the perpendicular line) the vertical
acceleration is getting bigger than
1 g, therefore the material starts lift-
ing from the trough bottom = material
throw.
m/min
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
cm/s
67
63
60
57
53
50
47
43
40
37
33
30
27
23
20
17
13
10
7
4
6
8
10
12
14
16
18
20 22
24 26
28 30
32
34
Average material speed
v
m
Eccentric radius R [mm]
K = 2
K = 1.8
K = 1.6
K = 1.4
K = 1
K = 1.2
n
s
= 380
K = 2.2
K = 2.5
K = 3
K = 4
K = 5
n
s
= 600
n
s
= 520
n
s
= 460
n
s
= 420
n
s
= 360
n
s
= 340
n
s
= 320
n
s
= 300
n
s
=
400
K = 3.3
Speed graph by rocker
mounting angle
β
= 30°
K
≥
2 material throw
K < 2 material sliding, v
m
speed not exactly definable
Distance between rockers L
max
:
–
Usually, the distance between the rocker arms on the trough along-
side is up to 1.5 meters, depending on the stiffness of the trough.
– By trough widths >1.5 m we do recommend to provide the trough
bottom side with a third, centrical row of rocker arms for stability
reasons.
Mounting position drive head ST:
For one mass shaker systems it is recommendable to position the
drive head slightly ahead of the center of gravity of the trough,
towards the discharge end.
Depth of thread engagement Z:
The depth of engagement should be at least
1.5 x the thread nominal width.
Angle of oscillation
α
:
The machine parameters, angle of oscillation
and revolutions should be determined in the ad-
missible area of operations (see chapter 5).
Screw quality:
The screw quality should be grade 8.8 secured
by the required tightening moment.
Rocker mounting angle
β
:
According to the relevant processing function of
the shaker conveyor, the rocker arms are posi-
tioned at
mounting angles between 10° to 30° in
relation to the perpendicular line. (The ideal com-
bination of fast conveying speed with high materi-
al throw is given by a rocker inclination angle of
30°.) The power input position of the drive-rod
from the eccentric drive should stay at right an-
gles to the rocker arms, this orthogonal position-
ing offers a harmonic course of the drive system
.