What Are the Different Types of Electric Linear Actuators?

An electric linear actuator is a device that converts an AC or DC electric motor's rotational motion into linear motion. The linear motion is generated by the motor rotating the screw of the push rod. Rotating the screw clockwise or counterclockwise allows the shaft to move up and down in a straight line, creating a push/pull effect against the load.

What Are the Types of Actuators?

1. Pneumatic linear actuator
   The pneumatic linear actuator consists of a simple piston in a hollow cylinder. A manual pump or external compressor will move the piston in the cylinder housing. As the pressure increases, the cylinder moves along the piston axis, generating the required linear force. It can be returned to the original retracted length by rebounding force or adding liquid to the opposite side of the piston.
2. Hydraulic linear actuator
   The hydraulic linear actuator is very similar to the pneumatic actuator, except that an incompressible liquid supplied from the pump is used instead of compressed air to move the cylinder in a linear motion. The hydraulic push rod includes control equipment and push rod accessories.
3. Electric linear actuator
   Electric linear actuators are also called electric cylinders. Electric cylinder actuators or electric lift cylinders use the rotational force (electricity) of the motor to convert the rotational force into linear movement (torque). Using the motor to rotate the screw of the push rod, the core will move up and down in a straight line, producing a push/pull effect on the load.

Analysis and Forecast of Global and China Electric Actuator Industry

The electric push rod, also known as linear actuator, is a small transmission part, which is composed of the drive motor, reduction gear, screw, nut guide sleeve, pushrod, sliding seat, spring, shell and turbine, micro-control switch, and so on. The linear actuator is sensitive in action, stable in operation, small, and high in accuracy. It can realize linear motion, replace hydraulic and pneumatic actuators, improve the control accuracy of the linear drive unit, and achieve high-precision operation.

With the development of electric actuator technology, various types and specifications of electric actuator series products have been widely used in many civil and industrial fields. According to different application fields, electric actuators can be divided into:

• Industrial putters, medical putters, home putters, etc.  Industrial push rods mainly refer to linear actuator used in mining and machinery manufacturing production lines.
• Medical pushrods are mainly used in products such as electric medical beds, making them more controllable and convenient.
• Home pushrods are mainly used in the driving system of lifting tables, functional sofas, etc., to realize multiple functions of smart home products, and make people's lives more convenient, faster, and more comfortable.

In recent years, with the development of modern computer technology and numerical control technology, the intelligent equipment industry has made great progress in machining accuracy and processing efficiency.  This has promoted the diversification of linear actuator applications and electric pushers. In addition to the wide application of rod products in traditional fields such as medical equipment, office furniture, home furnishings, and machine tools, their application in new fields such as wind power generation, rail transit, and electric vehicles are also gradually increasing.

The U.S. has well-developed, global, industrial and technological innovation capabilities. It is the world's major producer and consumer of electric actuators.  In Japan and South Korea actuator production is driven by automotive, medical equipment, smart home, and other industries. Market demand has also grown year by year. Electric actuators originated in Europe, and both Denmark and Germany have the world's leading linear drive product manufacturers. The downstream applications of electric actuators in the European market are more mature, and the demand for electric actuators is also relatively large.

As global light industry has shifted to developing countries in recent years, the electric actuator industry and related industries in developing countries, such as China has developed relatively quickly. China has now become the world's major producer and consumer of electric actuators, and several large-scale production enterprises have emerged. However, compared with developed countries such as Europe and Japan, China's electric actuators are relatively backward in terms of key technologies and processes. There is still a certain gap between the quality and performance of products and well-known foreign brands.

It is expected that in the future, with the development of global integration, and the continuous development of the automobile, smart home, medical equipment, and other products, light industrial industries such as electric actuators will continue to transfer from developed countries to developing countries such as China and India. With the progress of China's electric actuator series production technology and the expansion of production capacity, it is estimated that by 2025, the output of China's electric actuator series will exceed 4 million sets, and the demand will exceed 3.5 million sets. The development prospects of the electric actuator industry are broad.