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 into a system is for the necessity to move a payload in a linear fashion somewhat than a rotary one. As most standard electric motors are rotary, a linear actuator is used to convert 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. A variety of motor sizes can be mounted to those actuators relying on requirements.

Linear actuators have incorporated linear bearings that help the moving payload, as well as rotary bearings that assist 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 expensive customized parts. To extend the load capacity and stability of a linear actuator system, they are often paired up with the payload carried between them, reminiscent of in an XY gantry type stage. In this case, a shaft or belt is usually used to keep the 2 actuators in sync with every other.

Features of Linear Actuators

Linear Actuators have the next options:

High repeatability

Positioning accuracy

Smooth operation

Lengthy life

Easy maintenance or maintenance 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 used in industries including:

Packaging

Meals processing

Industrial vehicles

Factory automation

Material handling

Clean energy

Printing

Automotive

Machine instrument

Marine

Aerospace

Defence

Pharmaceutical

Types of Linear Actuators

Picking the correct type of linear actuator on your motion application may also 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 utilized 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 essentially the most commonly used strategies to supply the rotary motion, as they’re generally utilized in low cost and low precision applications. The ability of the actuator to ‘back drive’ is reduced over ball screw actuators due to the low effectivity 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 embrace agricultural equipment and manual lift systems, the place 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 principle this is similar to a regular 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 environment friendly methodology of changing rotary motion to linear motion. Stepper or servo motors are generally used to supply the rotary motion. Ball screw actuators are well suited to repeatable indexing and quick cyclic applications reminiscent of machine tools, scientific devices and medical systems.

Belt actuators work where a belt is carried between two pulleys and hooked up to the moving carriage, then as the belt rotates the carriage is pulled alongside the actuator. One of many pulleys is driven by a motor which is generally mounted perpendicular to the actuator and coupled utilizing a versatile coupling. They provide a relatively low-cost different, as they inherently have a lower level of precision. Belt driven linear actuators are very good for lengthy travel and high linear velocity applications similar to packaging and automated material handling systems.