Storage container

A storage container comprising:

• a storing section including a storage space capable of storing liquid and including an inflow port for causing the liquid to flow into the storage space;
• and
• a water sealing section including a coupling space linked to the storage space and a suction space linked to a suction source, the water sealing section being capable of sealing the coupling space and the suction space off from each other with water, wherein
• the storing section includes an inflow section connectable to a tube to allow the inflow port and an inner side of the tube to communicate and a volume changing section capable of changing volume of the storage space, and
• the volume changing section is deformed to increase the volume of the storage space when pressure in the storage space is about to rise to be equal to or higher than a reference pressure set in advance and is deformed to reduce the volume of the storage space when the pressure in the storage space is about to drop to be lower than the reference pressure, wherein:
• the storing section further includes a storing section main body having rigidity higher than rigidity of the volume changing section,
• the volume changing section is shaped to be accommodated on an inner side of the storing section main body when the pressure in the storage space reaches the reference pressure and also when the pressure in the storage space is lower than the reference pressure, and
• the storing section main body is shaped to define the storage space between an inner surface of the storing section main body and the volume changing section.