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 somewhat than a rotary one. As most typical electric motors are rotary, a linear actuator is used to transform rotary motion to linear motion.
The electrical 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 could be mounted to those actuators depending on requirements.
Linear actuators have incorporated linear bearings that support 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’ devices, making them simple to mount into existing machines and eliminating the need to design/manufacture very pricey custom parts. To increase the load capacity and stability of a linear actuator system, they are often paired up with the payload carried between them, similar to in an XY gantry style stage. In this case, a shaft or belt is often used to keep the two actuators in sync with each other.
Options of Linear Actuators
Linear Actuators have the following options:
High repeatability
Positioning accuracy
Clean operation
Long life
Easy upkeep or maintenance free
Protection ratings 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
Materials dealing with
Clean energy
Printing
Automotive
Machine software
Marine
Aerospace
Defence
Pharmaceutical
Types of Linear Actuators
Picking the proper type of linear actuator on 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 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 essentially the most commonly used strategies to provide the rotary motion, as they’re generally used 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 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 embody 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 precept this is similar to a normal 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 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 quick cyclic applications resembling machine instruments, scientific devices and medical systems.
Belt actuators work where a belt is carried between two pulleys and hooked up to the moving carriage, then because the belt rotates the carriage is pulled along the actuator. One of many pulleys is pushed by a motor which is generally mounted perpendicular to the actuator and coupled using a flexible coupling. They provide a comparatively low-cost various, as they inherently have a decrease stage of precision. Belt driven linear actuators are very good for long travel and high linear velocity applications such as packaging and automatic material handling systems.