Volume pump including a bellows and a suction valve and a discharge valve wherein the valves comprise a valve seat and a valve body and wherein a fixed section of the valve body includes a communicating flow path

A volume pump that transfers a transfer fluid, the volume pump comprising:

• a pump head including a suction port of the transfer fluid and a discharge port of the transfer fluid;
• a bellows fixed to the pump head, the bellows being configured to expand and contract to transfer the transfer fluid, and the bellows has a bottomed cylindrical shape forming a pump chamber on an inside of the bellows;
• a suction valve provided on the pump head to guide the transfer fluid from the suction port to the pump chamber;
• and
• a discharge valve provided on the pump head to guide the transfer fluid from the pump chamber to the discharge port, wherein:
• each of the suction valve and the discharge valve includes a valve seat and a valve body,
• each valve body is formed of a flexible material and includes:
• (i) a fixed section having a fixed positional relationship with the valve seat, and (ii) a valve section extending in a certain direction between a direction directed from the fixed section to the valve seat and a direction that the transfer fluid moves,
• an end of the fixed section of each valve body is screwed into the pump head, and
• the fixed section of each valve body includes a flow path communicating one of either the suction port or the discharge port, and a space between the valve seat and the valve body.