Patent ID: 8499713

Claim:
An application apparatus for applying a water-based coating to a painted workpiece, the apparatus comprising: a movable application nozzle unit; and first and second directional control valves; wherein the application nozzle unit comprises: a block having a coating reservoir defined therein for holding the water-based coating; a nozzle plate having a plurality of discharge ports defined therein for discharging the water-based coating from within the coating reservoir; a feed tube, provided on a top surface of the block, for feeding the water-based coating into the coating reservoir; front and rear plates provided on front and rear surfaces of the block, respectively; a pair of front and rear air-supplying tubes, provided on the front and rear plates, respectively, for supplying compressed air into gaps between the front plate and the front surface of the block and between the rear plate and the rear surface of the block; a pair of front and rear jet ports, defined between the nozzle plate and a lower portion of the front plate and between the nozzle plate and a lower portion of the rear plate, respectively, for emitting jets of the compressed air from the gaps to spread the water-based coating discharged from the discharge ports; a pair of front and rear water-supplying tubes provided on the front and rear plates, respectively; and spray ports, defined in the front and rear plates and communicating with the front and rear water-supplying tubes, for spraying pressurized water supplied from the front and rear water-supplying tubes, the first directional control valve allowing supply of compressed air to one of the pair of the air-supplying tubes on the basis of a direction of movement of the application nozzle unit, and the second directional control valve allowing supply of pressurized water to one of the pair of the water-supplying tubes on the basis of the direction of movement of the application nozzle unit.