Abstract: A drain for a compressed air system which drains the condensate without losing compressed air. The drain has a valve member with a cavity rotatable from a condensate receiving position to a condensate emptying position and a standpipe with its lower end communicating with the cavity in both positions and its upper end closed so that the compressed air which accumulates in the upper end of the standpipe expels the liquid from the cavity in the emptying position.

Abstract: An improvement on U.S. Pat. No. 4,058,240 in which the condensate is collected in cavities in the valve member having open ends on opposite sides of a plane normal to the valve member and perpendicular to its axis of rotation. The inner ends of the cavities intersect a vent opening extending along the axis of the valve member. The material of the valve member between the cavities provides better support for the valve seals. The vent provides more rapid drainage of the cavities so the cavities are substantially completely emptied each revolution, thereby increasing the drainage capacity of the device. The ball valve member could be hollow, in which case the entire interior of the ball would be available for collecting condensate.

Abstract: An automatic drain system for compressed air systems, air dryers, aftercoolers, separators and the like, which eliminates the loss of compressed air and is not clogged by sediment in the accumulated liquid or slurry.