Air conveyor

An air conveyor segment comprising:

• a first end and an opposite second end spaced from the first end;
• a main air duct extending from the first end to the second end;
• a conveyance surface being disposed adjacent to the main air duct and extending from the first end to the second end of the main air duct;
• a first wall extending from the first end to the second end, the first wall in the main air duct and separating the main air duct into an upper air duct and a lower air duct, a first wall opening in the first wall extending from the first end to the second end, the first wall opening fluidly communicating the upper air duct and the lower air duct;
• the main air duct comprising an outer wall defining a portion of the upper air duct, the outer wall comprising at least one opening extending through the outer wall and opening into the upper air duct, each at least one outer wall opening fluidly communicating the upper air duct with a source of pressurized air when a source of pressurized air supplies pressurized air through the opening and into the upper duct;
• a plurality of openings in the lower air duct away from the first wall, the plurality of openings in the lower air duct fluidly communicating the lower air duct with the ambient atmosphere and being disposed to impinge air flowing therethrough to the ambient atmosphere against the conveyance surface, and
• a valve assembly configured for selectively opening and closing the first wall opening, the valve assembly comprising a first valving member attached to the first wall and being movable between opened and closed positions, the first valving member closing the first wall opening when in the closed position, the first wall opening being open when the first valving member is in the opened position;
• and
• the first valving member being pivotally mounted to the first wall for movement between opened and closed positions.