True Linear Actuator for Servo Motor

Designed to convert servo angle to true linear displacement, as oposed to the trigonometric displacement of direct coupling. intended for the short-travel Z axis of CNC PCB milling machines.
Displacement = angle * K1 + K2
One-way force, push only. Requires a spring or gravity to pull the actuator back.
May be used with a flat surface or a roller bearing as the pushed surface. Bearing may be aligned to axis or displaced so that the resulting force vector is vertical.