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 (10) for the spray application of electrically conductive materials includes a shield (24) to prevent the build-up of electrically conductive flash deposits on preselected non-conductive surface areas (26) of the gun (10). By prohibiting the build-up of electrically conductive flash on preselected areas of the gun surface, the shield (24) is effective in preventing the completion of an electrical circuit between a charged electrode (18) and an electrically grounded gun...

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...

An electrostatic atomizer has a power source powering a charge injection device. The power source is arranged to vary the net charge injected by the charge injection device cyclically in accordance with a pattern of variation so that the net charge repeatedly increases to a higher value at or above a long-term breakdown value. The net charge injected is reduced by the power source to a lower value below the long-term breakdown value so that corona-induced breakdown is reduced. A method for elect...

An electrostatic atomizer comprises a power source for powering a charge injection device, a controller for controlling the net charge injected by the charge injection device, and a sensor for sensing breakdown precursors in the vicinity of the orifice and producing a feedback signal upon the occurrence of the breakdown precursors. The sensor is in communication with the controller and the controller is responsive to the feedback signal so that upon occurrence of the feedback signal, the control...

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 rotary atomizer spray painting device having a nonconductive fixed, axial tube for feeding paint, and having a nonconductive rotor supported for rotation in a nonconductive housing about the tube on air bearings or nonconductive ball bearings, and having turbine drive blades proximate one end thereof, the rotatable rotor supported inside of a nonconductive housing which has a high voltage electrical path therethrough, electrically connected to one or more symmetrically spaced forwardly project...

A high speed non-incendive rotary painting assembly including a high voltage power supply, an air supply means and a paint supply means is disclosed. The rotary painting assembly comprises a non-conductive body. A high speed, non-conductive turbine is connected to a non-conductive atomizer bell. In one embodiment, the non-conductive turbine is connected to a non-conductive rotatable shaft which mounts the non-conductive atomizer bell. In another embodiment, the non-conductive shaft is fixed. The...

A laboratory microchip includes a carrier with a micro spray tip projecting vertically out of a plane of the carrier. The carrier and spray tip are designed as a monolithic or single unit. The spray tip includes a passage channel which conveys the substances to be sprayed from a channel to a spray tip aperture. The channel is a part of a channel structure which is enclosed to the outside by a cover plate. The spray tip includes, on the sides of the spray aperture, an area which tapers conically ...

A spraying apparatus without electrical connections comprising means for controlling air supplies with signals generated with compressed air. The apparatus may further include a metering device which delivers metered amounts of powder to a spray gun and which may be controlled by the same compressed air which controls the air supplies.