How does a Linear Actuator work?

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

The electrical motor is generally related to the linear actuator by a flexible coupling or a belt, enabling the motor to be mounted either axially or perpendicular to the linear actuator. Quite a lot of motor sizes may be mounted to those actuators depending on requirements.

Linear actuators have incorporated linear bearings that help the moving payload, as well as rotary bearings that help either the lead screw, ball screw or belt pulleys. This then permits them to operate as ‘stand-alone’ units, making them easy to mount into present machines and eliminating the need to design/manufacture very pricey 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, equivalent to in an XY gantry fashion stage. In this case, a shaft or belt is usually used to keep the two actuators in sync with each other.

Features of Linear Actuators

Linear Actuators have the following features:

High repeatability

Positioning accuracy

Smooth operation

Lengthy life

Easy maintenance or upkeep free

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

Packaging

Food processing

Industrial vehicles

Factory automation

Material handling

Clean energy

Printing

Automotive

Machine tool

Marine

Aerospace

Defence

Pharmaceutical

Types of Linear Actuators

Picking the proper type of linear actuator to your motion application may also 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 various 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 essentially the most commonly used strategies to produce the rotary motion, as they’re generally used in low cost and low precision applications. The ability of the actuator to ‘back drive’ is reduced over ball screw actuators because of the low effectivity of the screw/nut. In some applications, this could be an advantage as it helps to keep the payload stationary whilst not in motion. Applications include agricultural equipment and handbook 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 round a ground screw thread. In precept this is similar to a standard 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 technique 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 reminiscent of machine instruments, scientific instruments and medical systems.

Belt actuators work the place a belt is carried between two pulleys and connected to the moving carriage, then because the belt rotates the carriage is pulled along the actuator. One of the pulleys is pushed by a motor which is generally mounted perpendicular to the actuator and paired using a versatile coupling. They offer a comparatively low-cost different, as they inherently have a decrease degree of precision. Belt pushed linear actuators are superb for long travel and high linear pace applications akin to packaging and automatic materials dealing with systems.