Psion Teklogix Vehicle-Mount Computer 8590 - Manual (Page 177)

8580/8590 Vehicle-Mount Computer User Manual D-7
Appendix D: Mechanical Dynamic Loading
Determining Insulating Effects
In our selected example, softer elastomer springs with the same construc-
tion could be used. In that case, it would still be possible that a Shore hard-
ness of A55 activates approx. 13 Hz.
• However, if the resonance deflections are too high (10 mm and more), the
natural frequency should be increased.
For example, using 3 elastomer springs with a diameter of 40 instead of 30
mm or using 4 instead of 3 springs.
The number, form, material type and arrangement of the elastomer springs can be
used to control the natural frequency. As a rule, constructions with vulcanized
fittings are used.
Important: Static tensile loads on the elastomer springs should be avoided, as
the elastomer can tear easily. A 8580/8590 should therefore never
be suspended from elastomer springs.
D.4.3 Determining Insulating Effects
A transmission function can be used to reach an exact calculation. However, we will
not detail this function here. The following equation is based on this transmission
function (very small damping factors of approx. 0.05) and is good for making
estimates: