How does a Linear Actuator work?

Linear actuators work by moving an object or piece of equipment in a straight line, moving an object extraordinarily accurately and repeatably if required. The primary reason for designing a linear actuator right into a system is for the need to move a payload in a linear fashion moderately than a rotary one. As most standard electrical motors are rotary, a linear actuator is used to transform rotary motion to linear motion.

The electric motor is generally connected to the linear actuator by a versatile coupling or a belt, enabling the motor to be mounted either axially or perpendicular to the linear actuator. A wide range of motor sizes might be mounted to these actuators relying on requirements.

Linear actuators have incorporated linear bearings that assist the moving payload, as well as rotary bearings that support either the lead screw, ball screw or belt pulleys. This then permits them to operate as ‘stand-alone’ gadgets, making them simple to mount into existing machines and eliminating the necessity to design/manufacture very costly custom parts. To extend the load capacity and stability of a linear actuator system, they are often paired up with the payload carried between them, comparable to in an XY gantry model stage. In this case, a shaft or belt is usually used to keep the two actuators in sync with every other.

Options of Linear Actuators

Linear Actuators have the next features:

High repeatability

Positioning accuracy

Clean operation

Long life

Easy maintenance or upkeep free

Protection rankings available for some models

Suitable for harsh environments

Compact design

Rugged and reliable

Safe operation

Versatile

Industries and applications for Linear Actuators

Linear Actuators can be utilized in varied applications that require a load to either be lifted, lowered, pushed, pulled, rotated or positioned. Linear Actuators are utilized in industries including:

Packaging

Food processing

Industrial vehicles

Factory automation

Material handling

Clean energy

Printing

Automotive

Machine device

Marine

Aerospace

Defence

Pharmaceutical

Types of Linear Actuators

Picking the right type of linear actuator to your motion application may help you achieve the best results. Lead Screw Actuators, Ball Screw Actuators and Belt Actuators are three types of linear actuators that can be utilized in varied applications to produce motion.

A Lead Screw Actuator uses a plain screw/nut arrangement to translate the rotary motion from a motor to linear motion. A manually pushed screw or an AC induction motor are probably the most commonly used methods to provide the rotary motion, as they are generally used in low price and low precision applications. The ability of the actuator to ‘back drive’ is reduced over ball screw actuators as a result of low efficiency of the screw/nut. In some applications, this can be an advantage as it helps to keep the payload stationary whilst not in motion. Applications include agricultural equipment and guide lift systems, the place safety and reliability are more critical than precision and performance.

A Ball Screw Actuator makes use of a high precision nut with recirculating ball bearings that rotate around a ground screw thread. In principle this is very similar to an ordinary ball race with the load being transmitted by the rolling balls. The significant advantages of this system are high-precision and low friction, giving a very environment friendly method of converting rotary motion to linear motion. Stepper or servo motors are generally used to provide the rotary motion. Ball screw actuators are well suited to repeatable indexing and fast cyclic applications corresponding to machine tools, scientific devices and medical systems.

Belt actuators work the place a belt is carried between two pulleys and attached to the moving carriage, then as the belt rotates the carriage is pulled alongside the actuator. One of the pulleys is driven by a motor which is generally mounted perpendicular to the actuator and matched using a flexible coupling. They offer a comparatively low-cost alternative, as they inherently have a lower stage of precision. Belt driven linear actuators are very good for long travel and high linear speed applications akin to packaging and automated material handling systems.