Pump device

A pump device comprising:

• a supply chamber to which a liquid-supply-side connection port is connected and that has a supply-side accommodation part configured to accommodate a predetermined volume of dialysate;
• a drain chamber to which a liquid-drain-side connection port is connected and that has a drain-side accommodation part configured to accommodate a predetermined volume of drain liquid;
• dividing membranes each being a flexible member attached to a corresponding one of the supply chamber and the drain chamber in such a manner as to close a corresponding one of the supply-side accommodation part and the drain-side accommodation part, the dividing membranes being displaceable relative to the supply-side accommodation part and the drain-side accommodation part in such a manner as to cause the dialysate to be suctioned into and discharged from the supply-side accommodation part through the liquid-supply-side connection port and cause the drain liquid to be suctioned into and discharged from the drain-side accommodation part through the liquid-drain-side connection port;
• and
• a pump body from and to which the supply chamber or the drain chamber is detachable and attachable with the supply-side accommodation part or the drain-side accommodation part being closed by the corresponding dividing membrane, the pump body including a driven part configured to move with activation of a drive source and in such a manner as to displace the dividing membranes.