The Principle and Function of Vacuum Generator

Vacuum Generator is a highly efficient, clean, economical, and compact vacuum component that uses positive pressure air sources to generate negative pressure. This makes obtaining negative pressure in places with compressed air or in a pneumatic system that requires both positive and negative pressure extremely easy and convenient. Vacuum generators are widely used in industrial automation, machinery, electronics, packaging, printing, plastics, and robotics. This article provides a detailed explanation of the principle and function of the vacuum generator.

Principle of the Vacuum Generator

The principle of the vacuum generator is mainly based on the jet phenomenon and the Venturi effect in fluid dynamics. Specifically, its working principle is as follows:

Compressed Air Power

Vacuum generator uses compressed air as the power source. High-pressure compressed air enters the vacuum generator through the inlet connected to the compressed air supply system.

Nozzle Design

The compressed air entering the vacuum generator passes through a carefully designed nozzle, which is usually convergent-divergent shaped. In this process, the airspeed sharply increases while the pressure correspondingly decreases. This is due to the fluid accelerating in the narrow passage, following the Bernoulli principle, which states that as the fluid velocity increases, its static pressure decreases.

Entrainment Flow

When the high-speed airflow is ejected from the nozzle, a low-pressure area is formed around the nozzle outlet. This low-pressure area can "entrain" the surrounding air into it. This phenomenon is called "entrainment flow."

Vacuum Generation

The jet airflow forms a low-pressure area in the suction chamber (or diffusion chamber), making the pressure inside the suction chamber lower than the surrounding atmospheric pressure, thereby generating a vacuum. As external air continuously gets entrained into the suction chamber to supplement the low-pressure area, the function of adsorption or extraction of the target object is ultimately achieved. Moreover, multi-stage vacuum generators enhance this process further by using multiple series of nozzles and expansion sections, generating a greater vacuum suction volume while consuming the same amount of compressed air.

Vacuum generators are widely used in various fields, and their main functions include:

Industrial Automation

Vacuum generators are widely used in the fields of machinery, electronics, packaging, printing, plastics, and robotics in industrial automation. In these fields, vacuum generators are often used for adsorption, handling, positioning, and other processes.