A pump includes a diaphragm vibrated by a piezoelectric element and a
case. An inlet orifice and an outlet orifice are disposed on an outer
surface of the case. An inlet path connects the inlet orifice to an inlet
and an outlet path connects the outlet orifice to an outlet. At least one
portion of the inlet orifice and at least one portion of the outlet
orifice are positioned higher than the diaphragm in the case, and
portions of the inlet path and the outlet path connecting to the inlet
orifice and the outlet orifice are positioned higher than the diaphragm.