What are electric linear actuators?

Linear actuators are a type of actuator that convert rotational motion in motors into linear or straight push/pull movements. Linear actuators are ideal for all types of applications where tilting, lifting, pulling or pushing with pounds of force are required. Electric linear actuators are often the preferred solution when you need simple, safe and clean movement with accurate precision and smooth motion control.

Electric linear actuators use a DC motor or AC motor with a series of gears and a lead screw to push the main rod shaft. The difference between actuators is determined by the size of the motor, which can range from 12v DC to 48v DC.

Static and dynamic are the load capacity variables for a linear actuators. Dynamic load capacity is the amount of force being applied when the actuator is in motion. Static load capacity is when the actuator is motionless and holding a load in place.

Actuators open automatic doors, move car seats forwards and back, and open and close computer disk drives. The basic principle behind a linear actuator is the concept of an inclined plane, where the lead screw of the actuator continues along a ramp of small rotational force.

How does an electric linear actuator work? 

An electric linear actuator typically consists of a motor, a lead screw or belt drive, and a mechanical linkage. The motor rotates the lead screw or belt, which in turn moves the mechanical linkage, typically a rod or a plate, in a linear motion. The amount and speed of the linear motion is controlled by the rotation of the motor.

When the linear electric motor rotates in one direction, the mechanical linkage moves in one direction along the lead screw or belt. When the motor rotates in the opposite direction, the mechanical linkage moves in the opposite direction. The speed and distance of the linear motion can be controlled by controlling the speed and duration of the motor rotation.

Some electric linear actuators use a feedback mechanism, such as a linear encoder or a potentiometer, to provide precise control over the position and speed of the mechanical linkage.

In summary, an electric linear actuator converts the rotary motion of the motor into linear motion of a mechanical linkage via a lead screw or belt drive, and the motion can be controlled by controlling the rotation of the motor.

Types of Electric Linear Actuators

There are several types of electric linear actuators, each with their own unique characteristics and advantages. Some of the most common types include:

• Screw-driven actuators: These use a lead screw and a nut to convert rotary motion into linear motion. They are known for their high thrust force and precision, but they can be slower than other types of actuators.
• Belt-driven actuators: These use a belt and pulley system to convert rotary motion into linear motion. They are known for their high speed and low noise operation, but they can be less precise than screw-driven actuators.
• Rack-and-pinion actuators: These use a gear system to convert rotary motion into linear motion. They are known for their high thrust force and speed, but they can be less precise than screw-driven actuators.
• Linear Motor Actuators: These actuators use linear motors, which generate force in a straight line, instead of rotating motors. They are known for their high speed, precision, and accuracy, but they can be more expensive than other types of actuators.
• Voice Coil Actuators: These actuators use a magnetic field and a coil to generate force. They are known for their high speed, precision, and accuracy, but they can be more expensive than other types of actuators
• Piezoelectric Actuators: These actuators use the piezoelectric effect to generate linear motion, They are known for their high precision and nanometer resolution, but they have relatively low force output and high cost.

The selection of a specific type of linear electric actuator depends on the specific requirements of the application, such as force, speed, precision, cost and environment.

Electric Linear actuators are used:

Electric actuators are used in a wide range of applications, including:

• Automation, such as assembly lines, conveyor systems, and packaging machines, to provide precise linear motion control.
• Robotics and other automated machinery to provide linear motion control for tasks such as grasping, moving, and positioning.
• Medical equipment such as adjustable beds, hospital beds, patient lifts, and surgical tables.
• Industrial machinery, such as machine tools, packaging equipment, and material handling systems.
• Aerospace and defense: such as aircraft and spacecraft for tasks such as deploying flaps and landing gear.
• Automotive industry, such as in electric vehicles, hybrid vehicles, and autonomous vehicles, for tasks such as adjusting the position of mirrors and seats, opening and closing doors and windows.

Electric linear actuator and servo motor

Electric linear actuators and servo motors are both types of electric motors that are used in motion control applications.

They can be used together in a control system to achieve precise control over linear movement. For example, a servo motor can be used to drive the lead screw or belt of an electric linear actuator, and a feedback mechanism, such as an encoder, can be used to monitor the position of the mechanical linkage of the actuator. This allows the control system to precisely position the mechanical linkage to a specific location.

Spindle and toothed belt axes ELGC and mini slides EGSC From Festo.

Compact, flexible, powerful

When it comes to extremely limited space in test and inspection systems, small parts handling, the electronics industry and desktop applications, the axis series ELGC and mini slide EGSC are a great option for various industrial automation solutions.

The spindle and toothed belt axes ELGC offer an outstanding internal guide and are designed to have virtually no gaps so they are protected from external influences and yet are still extremely durable and robust.

The mini slide EGSC with built-in linear guide for high guide precision and force absorption makes it the first choice for vertical motions in extremely limited spaces or for guided single linear motions.

A handling system based on the combination of ELGC and EGSC offers smart features for your machines and systems in factory automation. The optimum ratio of installation to working space, the unique "one-size-down" assembly system and the simple mounting and fastening technology ensure an optimum and efficient use of space and a streamlined system layout.