Features Of Linear Actuators

Linear actuators are almost always computer-controlled, although some can be guided by hand. A linear actuator can be powered by either hydraulic, pneumatic, mechanical, electromechanical and piezoelectric force.

Linear motion is achieved in most actuators through a ball screw design. A screw rod rotates in and out of a housing, causing linear motion. A timing belt drive, worm gear or direct drive is used to rotate a ball screw actuator. As the screw turns, it pushes a drive nut along the length of the screw, and this causes the rod to be pushed out. When this motion is reversed, the rod retracts. A cover over the screw keeps out dirt and other contaminants that could hinder movement. Even when it is loaded, special radial thrust bearings allow the screw to move freely.