Editing Stacked spring (section)

==Operation==
#When depressing the switch, the helical spring will take up the initial pressure and compress in a linear fashion; this lead-in period provides the pretravel that a snap-action spring cannot offer by itself, which will only snap by a fraction of this distance.
#Once the pressure in the helical spring reaches the buckling point for the snap-action spring or dome, that component will snap down into its unstable state, and actuate the switch.
#The buckling action will allow the helical spring to expand, reducing its pressure and providing a tactile event; the snap-action component will not release, because the force required to hold it down is lower than that required to buckle it, so the switch will sit comfortably in its actuated state without jitter.
#Although the snap-action component is held in place, the helical spring can be compressed further; this extended period provides overtravel (achieved without any motion in the snap-action component, which is now held firm).
#When releasing the slider back to the point where the switch actuated, it won't release, per step 3; the slider must be released further before the snap-action component snaps back up, providing hysteresis.