The main components of an electric linear actuator include a motor, screw, nut, and controller—all working together to create precise linear motion.
An actuator also has housing, limit switches, and feedback sensors, which help ensure smooth operation and prevent damage.
Together, these parts convert rotary motion into a straight-line push or pull, making actuators essential for automation.
Let’s take a closer look at the key linear actuator parts and their roles.
What Makes Up an Electric Linear Actuator?
Here’s an overview of the core components and their functions:
Motor
The motor is what drives the actuator, turning electrical power into movement.
Most actuators use DC motors because they’re compact and precise, but AC motors are better for handling heavy loads.
If fine-tuned movement is needed, like in automation or robotics, stepper motors provide more control.
Screw and Nut
The screw is a long, threaded rod that moves back and forth when the motor turns.
A lead screw is the standard option, simple and reliable, but a ball screw has tiny ball bearings inside that reduce friction and make movement smoother.
The nut sits on the screw and moves when the screw turns, pushing or pulling whatever is attached to the actuator.
In a ball screw actuator, the nut is packed with ball bearings to reduce wear and provide more precise movement.
Controller
The controller tells the actuator when to move and when to stop.
Basic models use simple switches, while more advanced ones connect to automation systems like PLCs to control speed and positioning.
Some controllers can also adjust how far the actuator extends, preventing overtravel.
Housing and Gear Assembly
The housing protects all the internal parts from dust, moisture, and damage.
Most are made from aluminum or steel, so they hold up well in rough environments.
Inside, there’s a gear assembly that adjusts the actuator’s speed and torque.
Some use spur gears for a direct drive, while others rely on worm gears, which hold their position better when power is off.
Limit Switches and Feedback Sensors
Limit switches prevent the actuator from overextending or retracting too far, cutting power when it reaches its set limits.
Feedback sensors track movement and positioning, making sure the actuator moves exactly how it should.
Some actuators use Hall effect sensors, which detect motion with magnets, while others use potentiometers or reed switches for positioning.
Mounting and Clevis Attachments
At both ends of the actuator, clevis attachments let it connect to machinery or mounting points.
These attachments allow the actuator to pivot as needed, making installation easier.
For high-load applications, reinforced clevis mounts prevent excessive wear over time.
Replacement Parts and Maintenance
If an actuator fails, replacing worn parts keeps it running like new.
A damaged screw or nut can cause uneven movement, while a failing motor might struggle to handle the load.
Faulty limit switches can lead to overextension, which can damage both the actuator and the equipment it’s controlling.To keep everything in top shape, check out AOX electric actuators for reliable replacement parts built for industrial use.
