Compact pump and diaphragm assembly used therein

A compact pump comprising:

• a hollow case which is symmetrical with respect to a motor rotation axis extending in a longitudinal direction;
• a diaphragm assembly which is disposed in the case at an upper position and includes a plurality of diaphragm units which form a plurality of pump chambers, respectively;
• and
• a swing body which is disposed in the case at a lower position and moves the plurality of diaphragm units in the longitudinal direction when swung by an eccentric rotary shaft, wherein:
• the plurality of diaphragm units have a plurality of through-holes at centers of bottom portions thereof, respectively;
• the swing body has a plurality of air introduction holes which communicate with the plurality of through-holes, respectively;
• the diaphragm assembly has a plurality of intake valve elements which open and close the plurality of air introduction holes, respectively;
• the case has an upper cover which is provided at an upper portion of the case;
• the upper cover has an exhaust hole formed along the motor rotation axis and a plurality of ring-shaped recesses which are disposed around and communicate with the exhaust hole;
• the upper cover has a plurality of tubular inner wall surfaces which define the plurality of ring-shaped recesses, respectively;
• the diaphragm assembly has a plurality of flanges which project from top ends of the plurality of diaphragm units in a direction perpendicular to the longitudinal direction, respectively;
• the diaphragm assembly has a plurality of tubular exhaust valve elements which are disposed in the plurality of ring-shaped recesses in a state that the plurality of tubular exhaust valve elements are in contact with the plurality of tubular inner wall surfaces, respectively;
• and
• the diaphragm assembly has a rib which is disposed at a center of the diaphragm assembly, extends toward the exhaust hole from the plurality of flanges, and connects center-side outer wall surfaces of the plurality of tubular exhaust valve elements.