User manual
F-4 8580/8590 Vehicle-Mount Computer User Manual
Appendix F: Mechanical Dynamic Loading
Approximate Solution for Elastomer Spring Selection
• Total vibrating weight of 8580: approx. 5 kg
F.5 Approximate Solution for Elastomer Spring Selection
This model applies to the oscillatory mass at the device’s center of gravity. This lies around
120 mm above the mounting surface of the group of springs and is also displaced from it. To
determine the spring constant for an individual elastomer spring, the leverages and arrange-
ment of the springs (here in a triangle) must also be considered.
Furthermore, each of the 4 elastomer springs connected in parallel must deliver one third of
the total spring constant, i.e., 78 N/mm / 3 = 26 N/mm.
Since ² = c / m, we obtain the following relationship:
Where:
m = oscillatory mass = 5 kg
f
e
= natural frequency = 20 Hz
c = spring constant in N/mm
mmN
f
m
f
mc
ee
/78039,0
1000
²4
22