An improved electrostatic spray gun is disclosed including an electrically conductive metal handle assembly, an electrically insulative barrel assembly, and an electrically insulative nozzle assembly terminating at its forward end in a small diameter discharge orifice through which the coating material is ejected. An ionizing electrode protrudes from the discharge orifice. The flow of material through the barrel and the nozzle assembly is controlled by a trigger actuated needle and seat valve as...

Electrostatic coating apparatus including apparatus for establishing an electrostatic field for indirectly charging atomized droplets of paint or other coating material discharged from an atomizer. A flexible tube is formed into an annulus and is positioned coaxially with the atomizer. Pins extend through the tube and have short ends which project towards a workpiece to be coated. The tube is formed from an insulating outer layer and a semi-conducting inner layer having a high distributed resist...

A voltage isolating device selectively electrically isolates from each other two points (13 and 15) of an electrically conductive flow medium having different electrical potentials along a flow path. The electrically conductive flow medium is conveyed in the inner space (18') of a freely protruding carrier (17') having at least one discharge opening (29). The carrier (17') moves back and forth between a first isolating position and a second docking position to allow a transfer flow. The discharg...

A spray coating device includes a ring (14) surrounding a spray device (4) radially spaced and supporting at least one electrode (28). Gas flowing across the ring (14) and electrode transmits electrical charges from the electrodes to particles of atomized coating material, downstream from a spray head (6) of the spray device (4). The electrical charging of the coating material is considerably increased thereby.

An electrostatic spray gun is disclosed which comprises a high valued resistance in the barrel portion of the gun, and a second resistor in the nozzle of the gun closely adjacent to a charging electrode projecting from the nozzle to provide safer operation.

An electrostatic air atomization spray coating system having a hand held spray gun, wherein a flow of air to the gun is sensed to control energization of a high voltage power supply for electrostatically charging spray particles, is characterized by a bypass valve on the spray gun which selectively permits air atomization spraying with or without electrostatics.

Apparatus is disclosed for resistively damping capacitively stored energy in electrostatic spray guns, wherein a fluid spray valve incorporates an electrode for carrying high electrostatic voltage, the electrode terminating in the spray valve and the spray valve having a conductor contacting the electrode and extending externally thereof. A resistive element at least partially encloses the spray valve and electrically contacts the conductor, permitting electrical conductivity while also permitti...

The invention relates to a process and apparatus for the electrostatic spraying of electrically conductive paint. Paint free of electric charge is intermittently fed from a main supply system to a buffer supply vessel, from which the paint is intermittently fed to a spray paint supply vessel which contains electrically charged paint. The paint in the buffer supply vessel is already electrically charged prior to the replenishing of the spray paint supply vessel from the buffer supply vessel. The ...

An apparatus is provided for transferring electrically conductive coating materials, such as water-based paint, from at least one source to one or more coating dispensers for discharge onto a substrate. One voltage block is provided to avoid the creation of an electrical path between one or more sources of coating material and the coating material which is electrostatically charged during a coating operation, and a secondary voltage block is provided between each of a number of individual spray ...

A spray malfunction detector system for electrostatic spraying apparatus having a sprayhead connectable to a high voltage source and for directing spray of charged particles of fluid towards an earthed target. The system comprises an earth circuit from the earthed target, a by-pass electrode located in the vicinity of the sprayhead and maintained in use at such a potential as to attract corona discharge from the sprayhead, and a current detector located in the earth circuit between the earthed t...