Diaphragm pump

A diaphragm pump comprising:

• a diaphragm including a deformation portion having a cup shape;
• a partition configured to close an opening portion of the deformation portion and form a pump chamber together with the deformation portion;
• a suction through hole extending through the partition;
• a suction passage communicating with the pump chamber via the suction through hole;
• a discharge through hole extending through the partition;
• a discharge passage communicating with the pump chamber via the discharge through hole;
• a driving mechanism configured to convert rotation of a motor into a reciprocating motion and alternately deform the deformation portion in a direction of increasing a capacity of the pump chamber and in a direction of decreasing the capacity of the pump chamber;
• a suction valve attached to the partition and configured to open the suction passage in a stroke of increasing the capacity of the pump chamber and close the suction passage in a stroke without increasing the capacity;
• and
• a discharge valve attached to the partition in the discharge passage and configured to open the discharge passage in a stroke of decreasing the capacity of the pump chamber and close the discharge passage in a stroke without decreasing the capacity,
• wherein the partition includes a seat surface on a side facing the pump chamber, and
• the suction valve includes a valve body configured to come into contact with or separate from the seat surface, and the valve body includes a leak structure configured to form a channel between the valve body and the seat surface.