A vacuum device for a material handling system includes a vacuum device
body and a sealing element. The vacuum device body has a vacuum
passageway in which a vacuum is generated in response to activation of a
pressurized air supply that forces pressurized air through a venturi
device. The sealing element moves to a sealing position to substantially
seal the vacuum passageway when the air supply is activated, and is urged
toward the sealing position via pressurized air that is diverted from an
inlet of the vacuum device to the sealing element. The sealing element
moves to substantially vent the vacuum passageway when the air supply is
deactivated. The vacuum passageway may be in fluid communication with a
vacuum cup, which seals against the object when the sealing element is at
the sealing position and the vacuum generating device generates at least
a partial vacuum in the vacuum passageway.