Product Description
EN-US · 30.30.01.01721 · 01 · 09/19
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3 Product Description
3.1 Description of the Mini Compact Valve
3.1.1 Suction of the Workpiece (Vacuum Generation)
The ejector is designed for vacuum handling of parts in combination with suction systems. The vacuum is
generated in a nozzle according to the Venturi principle, i.e. by using suction generated by the flow of ac-
celerated compressed air. Compressed air is channeled into the ejector and flows through the nozzle. A
vacuum is generated immediately downstream of the motive nozzle; this causes the air to be sucked
through the vacuum connection. The air and compressed air that have been removed by the suction exit
together via the silencer.
The venturi nozzle on the ejector is activated and deactivated using the suction command:
•
In the NO (normally open) variant, the venturi nozzle is deactivated when the suction signal is re-
ceived.
•
In the NC (normally closed) version, the venturi nozzle is activated.
•
In the IMP variant, the venturi nozzle is actuated using the same principle as the NC variant.
In the ejector variant IMP, the ejector remains in “Suction” mode if the power supply fails during auto-
matic mode. This prevents objects that have been picked up from falling off the suction cup in the event
of a power supply failure. This also applies when the ejector was in the “Venturi nozzle inactive” state
with the air-saving function activated. In this case, the ejector switches to “Venturi nozzle active,” i.e., to
continuous suction. When the power supply returns, the ejector remains in automatic mode with the air-
saving function activated. If the ejector is in blow-off mode when the power supply fails, the blow-off is
stopped and the ejector is set to “pneumatically OFF”. This prevents unnecessary consumption of com-
pressed air, thus saving energy and additional costs. When the power supply returns, the ejector remains
in “pneumatically OFF” mode.
An integrated sensor records the vacuum generated by the venturi nozzle. The exact vacuum level is
shown on the display and can be read from the IO-Link process data.
The diagram below shows the vacuum curve for when the air saving function is activated:
H1
H1-h1
H2
H2-h2
Vacuum
[mbar]
Vacuum on
Time [s]
OUT=on
OUT=off
The ejector has an integrated air saving function and automatically regulates the vacuum in suction
mode:
•
The electronics switch the venturi nozzle off as soon as the set vacuum limit value (switching point
H1) is reached.
•
When objects with airtight surfaces are picked up, the integrated non-return valve prevents the vac-
uum from dropping.
•
If the system vacuum drops below the limit value switching point H1-h1 due to leaks, the venturi
nozzle is switched back on.
•
Depending on the vacuum, the H2 process data bit is set once a workpiece is picked up safely. This
enables the further handling process.
