To manufacture a pump capable of delivering wind with a wind pressure by rotational movement like a bellows.

The ring pump comprises a discoidal air chamber, and a ring capable of deforming into an elliptical shape from a circular shape and capable of maintaining airtightness with the air chamber. One part of the ring is adhered between two air passages 5, 6 provided on an inner side wall surface of the air chamber, and by moving another portion around an interior of the air chamber along an inner wall of the air chamber while holding it, capacities of two spaces formed in the interior of the air chamber are changed, and pump action of taking in and discharging air from the air passages 5, 6 is carried out.