Patent ID: 7370946

Claim:
A pump comprising: a liquid chamber which stores a liquid having a conductivity and which includes an inlet port through which the liquid flows into the liquid chamber and an outlet port through which the liquid flows out of the liquid chamber; a reverse-flow preventing mechanism which prevents a flow of the liquid flowing into the liquid chamber through the inlet port and out through the outlet port to an outside of the liquid chamber from reversing; a pressure adjustment channel which communicates with the liquid chamber and which changes a pressure of the liquid in the liquid chamber; a first electrode which is provided on a wall surface which defines the pressure adjustment channel; and an insulating film which is provided on a surface of the first electrode and in which, when a predetermined voltage is applied to the first electrode, a wetting angle of the liquid on a surface of the insulating film is decreased to be smaller than a wetting angle of the liquid on the surface of the insulating film when the predetermined voltage is not applied to the first electrode.