An actuator is a component device responsible for activating or controlling movements in various types of machinery. It requires a source of energy, which it uses in order to operate the mechanism or system into which it was integrated.
These mechanical devices usually use a low amount of energy produced byelectricity, pneumatic pressure, hydraulic pressure,magnetic or thermal energy,or even manual operation. They convert the energy into mechanical motion, which the system uses to perform specific functions.
Now, a linear actuator is a type of actuatorthat converts energy to produce linear motion or movement along a straight line. This is in contrast to a rotary actuator, which produces rotary movement. Linear actuators are used in a variety of industrial applications, including manufacturing, agricultural, and construction machinery, as well as computer components, medical equipment, and various domestic tools. Some linear actuators are used in fields that require high-precision positioning to move linear stages and other instruments. These disciplines include the likes of microscopy and optics.
The major types of linear actuators are as follows:
Electric linear actuators
Electric linear actuators are mechanical devices powered by a motor and uses electric energy to convert rotary motion to linear displacement or straight-line, push-or-pull movement. Because they don’t use oil or other fluids, these actuators tend to be the cleanest type of linear actuators available,in addition to producing the least environmental impact.
Many electric linear actuators afford highly precise linear positioning capabilities. They are used in a wide range of applications, particularly for automation purposes where mechanisms or systems entail very exact displacements to specific positions.
Although electric linear actuators are the most readily available among all other types of linear actuators, they tend to be relatively more expensive, and not all of themare suitable for all kinds of environments. This doesn’t mean to say, however, that modern electric linear actuators are unreliable. As a matter of fact, the power capacity and toughness of actuators produced by reputable manufacturers have increased significantly in recent years.
Hydraulic linear actuators
A hydraulic linear actuator is a cylindrical-shaped device that contains a piston mechanism. Pressure is applied to the piston, which slides along the tube and is responsible for generating the force that creates linear displacement or movement along a single axis.Hydraulic linear actuators take advantage of the near incompressibility of liquids, using this to bring to bear a considerable amount of force. In fact, hydraulic actuators can hold the force constant even without the application of more pressure, because liquids almost don’t compress at all.
Although they can exert a large amount of force, hydraulic linear actuators can leak liquid, which couldsubject the device to quality- and maintenance-related problems. Furthermore, such actuators typically comprise numerous accompanying parts, which can add significantly to their heft.
Pneumatic linear actuators
Pneumatic linear actuators are like hydraulic linear actuators in that they typically have a cylindrical body with a piston. However, instead of a fluid, they use compressed air or vacuum.
One of the main draws of these actuators is that they tend to be safer when used in particular applications involving mechanical activity. They can be used in high-temperature environments, and because they don’t use a motor, explosions and similar risks can be avoided.
Nevertheless, the compressibility of air does make pneumatic linear actuators less efficient compared to those with hydraulic mechanisms. When weaker pressure is applied, the result is usually lower force and decreased speed. Because of this, pneumatic linear actuators are not always applicable for use in heavy duty applications.
These days, numerous types of actuators and other positioning technologies are available for an equally varied number of enterprises and industries. These devices and machinery can be precisely tailored to the needs of these customers.