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 first reason for designing a linear actuator right into a system is for the necessity to move a payload in a linear fashion rather than a rotary one. As most typical electrical motors are rotary, a linear actuator is used to convert 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. Quite a lot of motor sizes can 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 help either the lead screw, ball screw or belt pulleys. This then allows them to operate as ‘stand-alone’ gadgets, making them easy to mount into current machines and eliminating the need to design/manufacture very costly customized parts. To extend the load capacity and stability of a linear actuator system, they can be paired up with the payload carried between them, comparable to in an XY gantry fashion stage. In this case, a shaft or belt is often used to keep the 2 actuators in sync with every other.

Features of Linear Actuators

Linear Actuators have the next features:

High repeatability

Positioning accuracy

Easy operation

Lengthy life

Easy maintenance or maintenance 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 various applications that require a load to either be lifted, lowered, pushed, pulled, rotated or positioned. Linear Actuators are used in industries together with:

Packaging

Food processing

Industrial vehicles

Factory automation

Materials handling

Clean energy

Printing

Automotive

Machine tool

Marine

Aerospace

Defence

Pharmaceutical

Types of Linear Actuators

Picking the proper type of linear actuator on your motion application might help you achieve the very best results. Lead Screw Actuators, Ball Screw Actuators and Belt Actuators are three types of linear actuators that can be used in numerous applications to produce motion.

A Lead Screw Actuator makes use of 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 the most commonly used strategies to produce the rotary motion, as they are generally utilized in low price and low precision applications. The ability of the actuator to ‘back drive’ is reduced over ball screw actuators because of the low efficiency of the screw/nut. In some applications, this may be an advantage as it helps to keep the payload stationary whilst not in motion. Applications embrace agricultural equipment and manual lift systems, where safety and reliability are more critical than precision and performance.

A Ball Screw Actuator uses a high precision nut with recirculating ball bearings that rotate round a ground screw thread. In precept this is similar to a typical 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 really efficient methodology of changing rotary motion to linear motion. Stepper or servo motors are generally used to produce the rotary motion. Ball screw actuators are well suited to repeatable indexing and quick cyclic applications comparable to machine instruments, scientific instruments and medical systems.

Belt actuators work where a belt is carried between pulleys and hooked up to the moving carriage, then because the belt rotates the carriage is pulled along the actuator. One of the pulleys is driven by a motor which is generally mounted perpendicular to the actuator and matched utilizing a versatile coupling. They provide a comparatively low-cost different, as they inherently have a lower level of precision. Belt pushed linear actuators are excellent for lengthy travel and high linear pace applications akin to packaging and automated materials handling systems.