Patent ID: 8025363

Claim:
A liquid droplet jetting apparatus which jets liquid droplets of a liquid, comprising: a jetting head unit having a nozzle which jets the liquid droplets; an electric circuit board having a wiring and a circuit component which are connected to the jetting head unit and having one surface which is electrically insulated from the wiring and the circuit component; and a box-shaped head holder which supports the jetting head unit and the electric circuit board and which has an upper surface opening and a bottom plate in which a through hole is formed, wherein the jetting head unit and the electric circuit board are electrically connected with each other in the head holder; the jetting head unit is fixed to the bottom plate of the head holder to cover the through hole so as to airtightly close an inner space of the head holder with respect to an outside of the head holder; and the electric circuit board is fixed to the head holder to cover the upper surface opening so as to airtightly close the inner space of the head holder with respect to the outside of the head holder, so that the one surface, of the electric circuit board, which is electrically insulated from the wiring and the circuit component, faces the outside of the head holder.