Glossary · Pneumatics and hydraulics
Vacuum ejector
Also known as: Venturi vacuum generator, Vacuum generator
German: Vakuumejektor
In pneumatics, a vacuum ejector is a vacuum generator without moving parts that uses the Venturi effect: compressed air flowing through a nozzle creates a vacuum at a suction port, used for example with suction cups for gripping.
- Fluid power
In one sentence
A vacuum ejector creates vacuum from compressed air via the Venturi effect, without moving parts, e.g. for suction cup grippers.
Example
A robot's vacuum gripper uses compact ejectors with air-saving function and a vacuum switch that confirms the part is picked.
How it applies
- Engineering: Ejectors are compact and fast and can be placed close to the suction cups. Air-saving circuits switch the ejector off once the vacuum level is reached. Holding force depends on vacuum level, cup area and surface.
- Commissioning: Vacuum levels and switching points are set and tested with real parts, including porous or oily surfaces.
- Operation: Loss of compressed air or power can release the part, unless check valves or non-return functions hold the vacuum for a limited time.
- Documentation: Describe what happens to held parts on power or air loss (Ejection hazard, falling parts) and include cleaning of filters and silencers in maintenance.
Vacuum ejector vs. vacuum pump
A vacuum ejector needs compressed air and has no moving parts. An electric vacuum pump needs no compressed air and is more energy efficient for continuous high flow.