Patent ID: 7648219

Claim:
A liquid-droplet jetting apparatus for jetting liquid droplet, comprising: a liquid-droplet jetting head having a liquid droplet jetting surface in which a plurality of nozzles are arranged in a predetermined direction, the plurality of nozzles forming groups of the nozzles; a movable body which moves in the predetermined direction relative to the liquid-droplet jetting head, the movable body having a detector which detects jetting states of the nozzles, and a purge cap which is provided on the movable body and which is movable in the predetermined direction integrally with the movable body; a cap driving mechanism which is provided on the moveable body and which moves the purge cap between a purge position at which the purge cap covers a part of the liquid droplet jetting surface and a purge standby position which is apart from the liquid droplet jetting surface; and a controller which controls the movable body and the cap driving mechanism; wherein the controller controls the moveable body and the cap driving mechanism such that the purge cap is at the purge standby position when a jetting state of a nozzle of the nozzles is detected by the detector; further when the purge cap driven by the cap driving mechanism moves from the purge standby position to the purge position, the movable body is at a position at which the purge cap covers a jetting port of the nozzle being detected; and wherein jetting state detection is performed for each of the groups of the nozzles which is covered by the purge cap at a time, and when at least one of the nozzles belonging to one of the groups is detected to be in an abnormal jetting state, the nozzles belonging to the group are purged simultaneously; and the detector has a light-emitting element which emits light in a direction crossing the predetermined direction and a light-receiving element which receives the light from the light-emitting element; and the light emitted from the light-emitting element to the light-receiving element is blocked by liquid droplets jetted from the nozzles.