A bush (31) is fitted into a housing (10) and an ultrasonic pump
(12) is supported liquid tightly by the bush (31). The ultrasonic
pump (12) is constituted by a pump shaft (21) formed to include a
pump bore (22) passing through it axially and having upper and lower ends
which are open, and an ultrasonic vibrator (23) mounted on the pump shaft
(21) in the vicinity of the midpoint thereof in terms of the axial direction.
A liquid vessel.(16) is mounted in the housing (10) in a freely attachable
and detachable manner, and the lower end portion of the pump shaft (21)
is received inside the liquid vessel (16). A cap (15) is freely detachably
attached to the upper end portion of the housing (10) so as to cover the
upper end portion of the pump shaft (21). The top side of the cap (15)
is provided with a spray port (51), and a step portion (57) is formed
for supporting a mesh plate (14) at the periphery thereof at a position
below the spray port (51). A compression spring (42) is provided
between a portion of the top side of the cap and the mesh plate. The mesh plate
(14) is formed to have a multiplicity of minute holes (14a)
and is held in pressured contact with the upper end face of the pump shaft (21)
by the compression spring (42).
