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 primary reason for designing a linear actuator into a system is for the necessity to move a payload in a linear fashion fairly than a rotary one. As most standard electric motors are rotary, a linear actuator is used to transform rotary motion to linear motion.
The electrical motor is generally linked 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 variety of motor sizes may be mounted to these actuators depending 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’ devices, making them easy to mount into present machines and eliminating the need to design/manufacture very pricey custom parts. To extend the load capacity and stability of a linear actuator system, they can be paired up with the payload carried between them, resembling in an XY gantry style 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 options:
High repeatability
Positioning accuracy
Smooth operation
Long life
Easy upkeep 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 numerous 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 software
Marine
Aerospace
Defence
Pharmaceutical
Types of Linear Actuators
Picking the correct type of linear actuator for your motion application might help you achieve one of the 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 driven screw or an AC induction motor are the most commonly used methods to supply the rotary motion, as they are generally utilized in low value 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 will be an advantage as it helps to keep the payload stationary whilst not in motion. Applications include 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 around 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 method 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 such as machine instruments, scientific instruments and medical systems.
Belt actuators work the place a belt is carried between two pulleys and attached 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 matched utilizing a flexible coupling. They provide a comparatively low-cost different, as they inherently have a decrease level of precision. Belt driven linear actuators are superb for long travel and high linear speed applications similar to packaging and automatic material handling systems.