Being one of the most interesting actuator types, vacuum actuators work by artificially creating a state of vacuum inside of enclosed spaces. Today, we want to discuss a question – how do vacuum actuators work? But before we start, we need to clarify some concepts.

What Is A Vacuum Actuator?

Vacuum linear actuator is a mechanism that creates an artificial vacuum pressure to move its piston or diaphragm. This is similar to the way other actuators use electric energy, hydraulic pressure or compressed gases to produce motion force. Vacuum actuators can be found in a wide range of machines, from car engines to various air conditioning systems.

How Does A Vacuum Actuator Works And What Does It Consist Of?

The principle behind a vacuum actuator is fairly simple. It consists of an air-tight vacuum chamber with a diaphragm or a piston and a usual actuator rod. The vacuum chamber is connected to the vacuum-producing part of the device, and the actuator rod is connected to whatever mechanism the actuator provides motion to. When the vacuum state is reached and the air leaves the chamber, the diaphragm or piston is sucked with it, creating the motive force for the actuator rod.

The same mechanism can be seen in the usual drinking straw. The vacuum drains the air up the straw, and the liquid you want to drink follows the same course.

By increasing and decreasing the potency of the created vacuum, it’s possible to change the speed and magnitude of the movement created, so vacuum actuators are very useful in situations when the precise translation of motive force is necessary.

Examples Of  Vacuum Actuators Usage

This kind of actuators is used in systems that provide the source of vacuum – for example, car engines. In a car, an actuator is connected to the vacuum system via a set of hermetic tubes and is used to control the throttle.

Another usage of a vacuum actuator in a car is cruise control technology. A vacuum actuator is attached to the ‘gas’ pedal and is itself attached to the throttle valve via a cable. Cruise control computer sends a signal to the actuator, which makes the throttle engage or disengage accordingly.

Vacuum actuators also control the air conditioning, headlights, and even door locks in some cars, being a reliable alternative to electrical actuators.


Vacuum actuators require a specific set of other mechanisms to work, but when they do work, they’re undoubtedly effective. If your project meets the prerequisites to use those mechanisms, you have no reason not to do so.