Single flow direction miniature pump

Abstract

A pump for use in a doll having a transparent front torso through which is viewed simulated internal organs, the pump being connected to coiled transparent tubing for passage therethrough of a liquid-air mixture. The pump has a main body portion with a generally cylindrical recess having a circular surface with a coaxial annular groove in the surface and an arcuate groove disposed radially outwardly from the annular groove. An inlet aperture is disposed radially outwardly from the annular groove and is in fluid communication therewith while an outlet aperture is in fluid communication with the arcuate groove with the two grooves being interconnected by a groove segment. A one-piece diaphragm is provided with a flange adapted to sealingly engage the surface, the diaphragm having a deformable dome-shaped portion extending outwardly from the surfce to form a chamber, the diaphragm having a skirt portion fitting within the annular groove with the skirt having a cutaway portion in proximity to the groove segment. The diaphragm flange is also provided with a tongue portion arcuate in cross section for abuttingly engaging a surface of the arcuate groove to provide a check valve between the groove segment and the outlet aperture. The skirt portion is so configured within the groove to act as an inlet check valve.