Different Types of Actuators and How They Work

If you are a motor expert or someone who is gaining knowledge and experienced in this sector, you must be aware of actuators and their varied kinds. They serve a significant purpose in a machine, controlling its movements. There are different kinds of linear actuators that vary in actions and use different types of sources for power.

When you understand the difference between these actuators, you will be able to identify the correct type of actuator that would match the machine you are working with and refine its process. It will also enable you to troubleshoot any sort of issue without much hassle. Find more

What are Actuators?

Actuators are parts of a machine that work on the feedback they receive from a specific control signal for movement. It is given power for action and creates certain motions that vary according to the machine and its purpose. It works on the mechanism of hydraulic, electrical, or wind energy, which are converted into a mechanical force. In other words, actuators are devices in a machine that facilitates its movement. You can easily compare it with the muscles of the human body that converts energy into physical movements that allow the functioning of the hands and legs.

Source: Assembly Magazine

Types of Actuators

The different kinds of actuators based on their form of motion and energy source used by them are highlighted below.

  • Electric Linear Actuator

These actuators function by enabling movements in a straight line. A piston makes to and fro motions based on the electric signal it receives and can work on movements like pushing, blocking, pulling, clamping, lifting, descending or ejecting. These actuators work in a high-speed motion with a gearbox that controls their level of impact. If the connection polarity is switched to battery from motor, then the actuator’s motor rotates in the opposite direction.   

Source: Creative Mechanisms
  • Electric Rotary Actuator

These actuators also work on electrical energy as their motion is dependent upon it. They can work on a fixed angle or can have continuous movements like in the case of stepper motors or servo motors. The electric rotary actuators can be a combination of a multi-stage helical gearbox, an electric motor and a limit switch. Their operation process can begin in a magnetic field when a current-carrying conductor comes in contact. A relative force is created that aligns to the field’s flux density, its current flow and dimensions. This ensues electromotive force-generating torque and rotation.

  • Hydraulic Linear Actuator

These are similar to linear actuators, with the only difference being that they perform on unbalanced pressure applicable on a piston with hydraulic fluid in a cylinder which is hollow in nature that can create a strong enough torque capable of moving an external object. Their main advantage is that they are able to generate a massive torque amount. A single hydraulic linear actuator can make a movement in only one direction, and it requires a spring to work in the reverse motion. On the other hand, a double hydraulic linear actuator works on both ends.

Source: Yacht Bits
  • Hydraulic Rotary Actuator

Making use of an incompressible, pressurized liquid that allows rotation within mechanical devices is the way in which hydraulic rotary actuators function. The rotational components used in them can either be circular shafts containing keyway or bolt pattern tables that are used to mount other components. Their shaft (single or double) can work when the helical spline teeth connect with the piston splines corresponding to them, making rotational motion through the conversion of linear movements. 

  • Pneumatic Linear Actuator

Simple and cost-effective, these actuators can work on creating movements by using compressed air. They retract or extend the piston or use a carriage (in rare cases) that runs on a cylindrical tube or driveway. The piston gets retracted with the help of a supply of fluid from the other end or simply using a spring. In a relatively small footprint, pneumatic linear actuators can achieve torque and high speed. They do not get damaged easily even with hard stops and provide rapid point to point motion, a decisive advantage. They are typically used in devices that need to be resistant to difficult conditions, for example- high temperatures. They can also be used in explosion-proof devices.  

Source: txele.net
  • Pneumatic Rotary Actuator

The pneumatic rotary actuator devices produce oscillatory motions after coming into contact with compressed air. These are similar to the pneumatic linear actuators as their designs are also simple, long-lasting and can work in challenging environments. Standard configurations used in these actuators are vane design, rack and pinion, and scotch yoke. The racks in these actuators can be multiple, double or single racks that help in rotary movements.

  • Piezoelectric Actuator

Groups of ceramic-like solids that are able to react to electric charge are Piezo materials. They can expand or contract in order to generate energy when mechanical force is applied to them. A Piezoelectric Actuator can create fast response strokes and short high frequency when electrical signals allow it to make movements. These movements are parallelly aligned to the electric field, often. The actions can also be orthogonally aligned when the transverse piezoelectric effect is applied to the device.

You can choose the proper actuator depending on factors like availability of suitable power source, precision, safety concerns, environmental concerns, kind of movement required as well as official guidelines to work. Keeping a regular check on your mechanical device, measuring the data of performance and replacing the obsolete parts can help you to maintain and manage your actuators.

Whether you need linear actuators immediately or in the near future that can work best on your device is a thought that might keep bugging you, so without stressing too much over this, you can visit Tuli Shop online and arrange the perfect fit for your device within minutes! It is ‘the’ destination when it comes to linear motor actuators, ball transfer units, bearings and much more. Your worry to find the essential part of the motor device you own ends here. Make a call today to get simple solutions to your needs or request a quote.