Automatic spray gun

An automatic spray gun for use in an automatic spray system which is a modular unit, wherein each working component is a separate module that can be removed from and re-assembled on the spray gun body itself for cleaning, repair and replacement without disturbing the setting of the gun body in the automatic spray set-up, such as distance from the work pieces to be sprayed, angle and the like. The needle valve which stops and starts the flow of liquid to be atomized and sprayed is operated by an air pressure piston and cylinder component which is a separate module and designed in a way whereby the pressurized air which powers and initiates operation of the piston and cylinder module can also be utilized to start and stop the flow of a separate source of pressurized air to atomize the liquid as it flows from the nozzle orifice and to delay the stop of atomizing air until after flow of pressurized air to hold the needle valve in its open position has been stopped. The atomizing component of the spray gun, the needle valve component, the fluid regulator component, nozzle and nozzle block component are each separate modules which can be removed from and re-assembled on the gun body without disturbing its setting in the automatic spray set-up.