Accuracy and repeatability are dominated by electric actuators, which makes them perfect for multi-point positioning applications. Electric actuators can precisely regulate their position and reproduce it with the same motion profile because voltage and current are easier to manage than air pressure. Compared to rotary actuators, electric linear actuators offer incredibly high precision.
Linear Actuators
The type of actuator known as a linear actuator transforms the rotational motion of motors into straight or linear push/pull movements. For any application requiring tilting, lifting, tugging, or pushing with pounds of force, linear actuators are the best choice.
Electric linear actuators are frequently the go-to option when you need a straightforward, secure, clean motion with precision and fluid motion control. Linear actuator types include the following:
• Hydraulic actuators
Similar to how heavy construction equipment frequently runs on hydraulic pressure, they are primarily employed for moving huge weights.
• Pneumatic actuators
They are better for rapid applications, in contrast, where heat increases are negligible thanks to the lightweight design and reduced friction of the parts.
• Electro-Mechanical actuators
Compare favorably to the other two options in terms of precision and accuracy.
Rotary Actuators
A device that generates rotary motion from an energy source is known as a rotary actuator. The rotation is produced by the simplest actuator of this kind using linear motion in a single direction.
Electrical rotary actuators use electric motors or another type of electrical energy source. Although rotational actuators can also employ hydraulic energy from pneumatic tubes or mechanical energy from springs, this form is the most typical. The following are some types of rotary actuators:
• Manual Rotary Actuators
A worm drive is frequently used in manual rotary actuators to improve the torque that a worker can physically apply to close a valve.
• Electric Rotary Actuators
Usually, a worm-gear reducer is used to drive electric rotary actuators. The valves are moved between the open and closed positions using reversible motors.
• Rack-and-Pinion Rotary Actuators
In rack-and-pinion designs, the rack or racks are propelled past the pinion by at least one cylinder and occasionally two or four.
• Scotch Yoke Rotary Actuators
Scotch-yoke actuators also use cylinders; they are typically single-acting with spring returns.
• Helical Actuators
Typically, pneumatic pressure is used with the helical rotary actuator style.
• Electrohydraulic Actuators
In order to benefit from each, electrohydraulic actuators combine electrical hydraulic pumps with conventional hydraulic actuators.
How Rotary and Linear Electric Actuators Differ From One Another
A linear actuator provides motion in a straight line back and forth. The distance traveled, velocity, and acceleration is essential performance indicators.
Electric linear actuators have a crucial distinction that might occasionally be misunderstood because a rotating electric motor produces the motion. Thus, an electric linear actuator transforms rotary motion into linear motion.
On the other hand, a rotary actuator produces motion that revolves around an axis. Most rotary actuators have an infinite range of motion, ranging from a single degree or even less to several rotations. The angular distance traveled, the torque exerted, the velocity and the acceleration are essential performance characteristics.
The Bottom Line
With their simple installation, integration, and operation, high positional accuracy, high repeatability, shallow maintenance requirements, high level of ruggedness, and ability to tolerate inclement weather, linear actuators have several advantages.
On the other hand, rotating actuators have hollow shafts, zero backlashes, any degree of rotation, high torque availability, compatibility with a wide range of diameters, and very little maintenance.
Linear actuators are used to translate from one position to another. Pneumatic linear actuators cannot be stopped mid-movement. However, electric linear actuators can. They are, therefore, a valuable option for moving objects a short distance in a straight line and, more broadly, for material handling jobs.
Rotary actuators enable accurate angular movement in applications like robot joints. Other instances include the operation of valves and the motion of conveyor gates.