Part 1: What is an Electric Linear Actuator? Definition & Types Explained

Electric linear actuators play a vital role in modern machinery, offering a reliable solution for converting electrical energy into linear motion.  These versatile devices power applications ranging from industrial automation to home appliances.  In this white paper series, we’ll dive into the fundamentals of electric linear actuators, their working principles, types, and how to select the right actuator for specific applications.

 

 

What is an Electric Linear Actuator?

An electric linear actuator is an electromechanical device mainly composed of a motor, a set of gears, and a motion mechanism consisting of a worm and tube. It converts the motor’s rotary motion into linear motion by driving the gears and worm gear.

 

Unlike rotary actuators, which create rotational movement, electric linear actuators are designed to move objects along a straight line. They are commonly used in applications that require precise positioning, such as lifting, lowering, pushing, or pulling loads.
 
If you want to know more about the components of an electric actuator, please read our following white paper series.
 

 

How Do Electric Linear Actuators Work?

The core mechanism of an electric linear actuator includes a motor (often DC or AC), a lead screw, and a nut. As the motor rotates, it drives the lead screw, causing the nut to move along the screw’s axis. This movement translates into linear motion, which is used to perform tasks such as opening windows, adjusting hospital beds, or automating industrial processes. 

 

Here’s a step-by-step breakdown of how they work:

1. Power Input: The actuator receives electrical energy from a power source, such as a battery or direct electrical supply.
2. Motor Activation: The motor begins rotating, generating torque.
3. Screw Mechanism: The motor’s rotation drives a threaded lead screw, which moves a nut attached to the load.
4. Linear Motion: The nut’s movement creates linear motion, allowing the actuator to push, pull, or lift the load.

Modern electric linear actuators often include advanced features like position sensors, limit switches, and feedback systems for greater control and precision. This makes them suitable for high-precision tasks in industries such as robotics and medical equipment.
 

 

What Are the Advantages and Disadvantages of Electric Linear Actuators?

1. Advantages:

• Precision and Control: Electric linear actuators provide accurate and repeatable positioning, ideal for automation tasks.
• Energy Efficiency: They consume less power than hydraulic or pneumatic actuators, particularly in static hold applications.
• Low Maintenance: With fewer moving parts and no fluid systems, they require minimal upkeep.
• Versatility: They can operate in various environments and are easily programmable for complex movements.
• Quiet Operation: Compared to hydraulic and pneumatic systems, electric actuators operate more quietly.
   

2. Disadvantages:

• Force Limitations: Electric actuators produce less force compared to hydraulic systems, limiting their use in heavy-duty applications.
• Dependency on Power Supply: A consistent power source is essential, which may not be ideal for all settings.

 

 

What Are the Different Types of Electric Linear Actuators?

Electric linear actuators come in various types to meet diverse application needs. Linear actuators, lifting columns, gear motors, and others all have their unique features and strengths. Discover below the list of the different types of actuators and adapt to the needs of equipment manufacturers.

 

1. Parallel electric actuators

The motor is parallel to the worm gear. Parallel electric linear actuators are usually driven by spur gears, which offer a wider range of gear ratios. These actuators allow for a greater range of loads and speeds but aren’t as quiet as actuators with worm gearing.

 

MA2	TA16

 

2. Right angle or "L" shaped electric actuators

The motor is placed perpendicular to the worm gear. A worm gear usually drives L-shaped electric linear actuators. These actuators offer fewer gear ratio choices than spur gear motors but are quieter and offer increased irreversible force.

 

TA23	TA43

 

3. In-line electric actuators

The motor is in line with the worm gear. In-line electric linear actuators, therefore, have a longer retracted length. They are usually driven by a set of planetary gears and are specifically designed to fit into tight spaces. However, they have a higher noise level.

 

JP4	VN2

 

4. Dual engines

Dual motors operate in two different directions, independently or simultaneously. They are usually driven by gears with a worm wheel and, therefore, offer a quieter movement.

 

TT1

 

5. The electric sliding actuators

Electric slide actuators allow linear movement without the use of an outer tube. The front attachment is linked to the nut, which moves along the worm gear.

 

TA5P	TA25

 

Discover our entire range of electric linear actuators.

 

6. Geared motors

Gearmotors allow the design of economic and versatile systems when combined with one or more worms. Compact, they are usually driven by gears with a worm wheel and are an ideal choice for achieving mechanical synchronization.

 

TGM3	TIG1

 

Discover our entire range of geared motors.

 

7. Variable height electric columns

We manufacture lifting columns for industrial, medical, and ergonomic applications. They allow the vertical movement of high loads while maintaining a high level of stability. Our industrial and medical columns are designed for applications such as medical beds, bariatric beds, or industrial workstations with adjustable heights. Thus, they preserve the safety and comfort of all users.

We also offer a range of ergonomic columns that comply with the BIFMA standard for variable-height offices. This range offers different colors, shapes, orientations, and a 2 or 3-tier design.

 

TL18AC	TL31K

 

Discover our entire range of electrical columns.

 

8. Electric frames for standing desks

We provide electric frames for height adjustment of desks and worktops. Available in several shapes and colors, they allow the design of sit-stand, straight, parallel, angled, or 120° desks. Delivered in pre-assembled kits, they offer quick and easy assembly. With smooth, quiet movement, the electric frames are the ideal solution for ergonomic desks in the workplace and at home.

 

TEKaiir	TEK30

 

Discover our entire range of pre-assembled kits for ergonomic desks.

 

You now know more about how electric actuators work, the different types of actuators, and their advantages. Find out how to choose an electric actuator according to your needs and constraints.

 

 

How to choose an electric linear actuator?

 

Selecting the correct electric linear actuator is crucial for the success of any electrical equipment development project. Actuators suit a wide range of applications, but each project has its unique requirements. To identify the most suitable electric linear actuator, consider several critical factors: the speed of operation, load capacity, duty cycle, spatial constraints, and the operating environment.

 

1. Load to be pushed

This includes not just the weight but the direction of movement (e.g., push, pull, lift) and the distance. The load affects the actuator's design and the safety measures required.

 

2. Required speed of movement

High speeds under heavy loads can lead to rapid wear and tear, shortening the actuator's lifespan. Each actuator has a maximum speed and load capacity that shouldn't be surpassed to prevent damage.

 

3. Duty cycle

The duty cycle, or the balance between operating and idle times, significantly impacts the choice of an actuator. A higher-duty cycle demands robust materials and designs to ensure longevity and prevent overheating or mechanical wear.

 

4. Available installation space

Spatial considerations also influence actuator selection. The available space within the equipment dictates the actuator size and configuration (e.g., parallel, L-shaped, in-line). For instance, in-line actuators, with their compact design, are ideal for limited spaces.

 

5. Environment

Factors such as indoor or outdoor operation, exposure to contaminants, moisture, and the need for intensive cleaning, dictate the actuator's design and protective measures.

 

By carefully evaluating these aspects—load capacity, speed, duty cycle, space, and environment—you can choose the right electric linear actuator for your project, ensuring performance, durability, and reliability.

 

With more than 15 years of experience in the manufacturing of electric actuation devices, TiMOTION supports equipment manufacturers from all sectors in their product development projects. Industry, medical, domestic, or professional furniture, we manufacture complete solutions and customize our devices to the specific needs of our customers.

 

Want to learn more about electric linear actuators? Contact a local sales representative

 

 

Frequently Ask Questions

 

1. What is the purpose of an actuator?

Actuators are devices designed to convert electrical, hydraulic, or pneumatic energy into mechanical motion. They serve to control a mechanism or system by moving or controlling a mechanism or system, enabling automated or remote control operations.

 

2. What are the examples of an actuator?

Actuators find versatile applications across numerous fields, enhancing functionality and automation. 

• At home automation, they adjust comfort beds and kitchen extractor hoods. 
• Healthcare benefits from actuators in medical care bedding, hospital beds, medical chairs, and patient lifts, facilitating patient care and mobility. 
• Ergonomically, they enable adjustments in height for desks and assist in media setups through screen and TV lifts. 
• In industry fields, actuators are crucial in agriculture, operating machinery like combine harvesters, sprayers, and tractors, and controlling ventilation systems and solar shading systems, including pergolas and sun shading louvers, optimizing environmental conditions and energy use.

 

3. What is an actuator vs motor?

An actuator is a broader term for devices that produce motion, often used for specific control actions, such as opening a valve. A motor is a type of actuator that converts electrical energy into rotary motion. Motors can drive components directly or be part of a larger actuator system.

 

 

Further reading:
→	Part 2: Components Of An Electric Linear Actuator
→	Part 3: Electric Linear Actuators With Integrated Safety Option
→	Part 4: Load And Speed Characteristics Of An Actuator
→	Part 5: Dustproof And Waterproof Linear Actuator's IP Rating
→	Part 6: Electric Linear Actuators With Feedback Sensors
→	The Ultimate Guide To Actuators
→	How To Choose An Electric Linear Actuator?
→	Advantages And Drawbacks Of Three Types Of Actuator Systems: Pneumatic, Hydraulic, And Electric