Liquid droplet jetting apparatus

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 which has a wiring and a circuit component connected to the jetting head unit, and which has, one surface electrically insulated from the wiring and the circuit component, and has, on the other surface opposite to the one surface, a plurality of connectors electrically connected to the wiring and the circuit component;
• 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;
• and
• a control board which controls the jetting head unit;
• wherein 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;
• the jetting head unit and the electric circuit board are electrically connected to each other in the head holder via a first wiring member connected to at least one connector among the connectors;
• the control board and the electric circuit board are electrically connected to each other via a second wiring member connected to another connector among the connectors;
• and
• the electric circuit board is fixed to the head holder to cover the upper surface opening of the head holder so as to airtightly close the inner space of the head holder with respect to the outside of the head holder, so that the surface on which the connectors are provided faces the inner space of the head holder.