These two mounting
methods were devised to protect PC boards from vibration when installed
in the engine compartment of a car. They could also be used in other
applications where vibration is a problem. Method 1 involves rigidly
mounting the PC board inside a diecast box and then mounting the box
itself to provide vibration isolation. As shown, small grommets are
installed in suitably sized holes in the sides of the box. The box is
then secured to angle mounting brackets using M4 screws, washers and
nylock nuts. Method 2 involves mounting the diecast case onto the
chassis of the car and then mounting the PC board as shown, using M3
screws, grommets, hollow spacers and nylock nuts. In this case, the
grommets are fitted into suitably sized holes in the PC board itself.
Once the nuts are tightened, the PC board should be able to move
slightly, relative to the box. If there is not enough space on the board
to fit the grommets, then Method 1 is the way to do it.
Author: David Boyes – Copyright: Silicon Chip Electronics