The random number drawing machine has a set of numbered balls (B) that are tumbled inside a rotating drum (1) made of a transparent material. The balls are lifted upward toward the top of the drum by a jet of air injected (3) at the bottom of the drum. Balls can leave the drum singly, through a hole (4) at the top. A surface (5) inside the drum projects into the interior of the drum, and is positioned adjacent to the hole through which the balls leave the drum. The face of the surface is tilted to guide a ball which bounces of it toward the exit hole. The projection does not extend the full width of the drum. A retaining rod (7,8) traps a ball as it emerges. The ball may be returned to the draw by reducing air flow and/or retracting the retaining rod (8) so the ball falls back into the drum. The balls can be loaded via a curved upright tube (17) at the side of the drum.
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