Fluid supplying apparatus, fluid ejecting apparatus, and fluid supplying method

A fluid supplying method for supplying fluid through a fluid supplying passage from a fluid supplying source, which is provided at an upstream side, toward a downstream side, the fluid being supplied as a result of operation of a pump that includes a pump chamber and a first displacement portion, the pump chamber being formed as a part of the fluid supplying passage, the first displacement portion being able to become displaced in such a way as to increase or decrease capacity of the pump chamber to drive the pump, the fluid supplying method comprising:

• closing the fluid supplying passage as a result of operation of a pressure chamber and a second displacement portion, the pressure chamber being formed as a part of the fluid supplying passage at a downstream position viewed from the pump chamber, the second displacement portion being able to become displaced in such a way as to increase or decrease capacity of the pressure chamber, the second displacement portion being displaced in a direction for decreasing the capacity of the pressure chamber in accordance with negative pressure that is applied from the downstream side of the fluid supplying passage to close the fluid supplying passage;
• and
• opening the fluid supplying passage by reducing internal pressure of a pressure reduction chamber that is formed next to the pressure chamber and is partitioned from the pressure chamber with the second displacement portion being formed as a partition between the pressure reduction chamber and the pressure chamber and applying negative pressure to the second displacement portion as a result of pressure reduction to cause the second displacement portion to be displaced in a direction for increasing the capacity of the pressure chamber while suppressing the displacement of the first displacement portion in a direction for increasing the capacity of the pump chamber to open the fluid supplying passage.