Abstract: Methods and apparatus are disclosed for spraying powder into the interior of welded hollow can bodies from a spray gun mounted to the welding arm of a can forming machine. The spray gun can either apply a stripe of highly charged powder on the welded seam areas of hollow can bodies, or can simultaneously apply a coating of powder having a first thickness on the longitudinally welded seam areas and a second thickness less than the first thickness on the remainder of the interior surface. Air is vented off from the powder flow being transported through the welding arm so that the powder to air ratio is increased. Air is introduced at the downstream end of the welding arm to provide a suction force to help draw the powder flow through the welding arm and to increase the velocity of the powder flow for better tribo charging of the powder in the gun and to improve spray pattern stability.

Abstract: A powdered lubricant applicator is provided which utilizes a venturi nozzle to draw powder from a fluidized hopper. The amount of powder delivered from the hopper is controlled by the air flow rate through the nozzle and by the length of time that the air flows through the nozzle. As air passes through the nozzle, powdered lubricant is drawn from the fluidized hopper and passed with the air along a delivery tube. As the fluidized powdered lubricant passes along the delivery tube, additional "atomizing" air is introduced into the delivery tube to assist powder delivery to the destination mechanism to be lubricated. In addition, fluidizing air is added to the delivery tube. The air used to assist the powder delivery (i.e., the atomizing air) and the air used to fluidize the powder (i.e., the fluidizing air) impact the powder delivery. Three pressure regulators are used to independently control the flow air, the atomizing air and the fluidizing air.

Abstract: A rotary atomizing electrostatic coating apparatus includes a plurality of shaping air nozzles for expelling shaping air having a pressure of about 80-250 kPa at an exit of each shaping air nozzle and having an amount of air to be expelled per nozzle of about 10-20 Nl min. Each shaping air nozzle has a diameter of about 0.6-1.5 mm. The number of shaping air nozzles is determined so that a summation of diameters of all shaping air nozzles is equal to between about 1/6-1/4 times an entire circumferential length of a greatest outside diameter of the atomizing head.

Abstract: An apparatus and method are disclosed for the aerial spraying of agricultural chemicals with improved spray deposition and reduced drift. The spraying apparatus includes two oppositely charged sets of spray nozzles which may be fitted onto an aircraft. Both sets include one or more nozzles having spraying tips which produce a hollow cone spray pattern, and at least the tips of these nozzles are constructed of a substantially non-conducting material. Cylindrical electrodes are positioned concentric to the nozzle tips for inducing an electrostatic charge upon liquid spray emitted from the nozzles. The electrodes are in turn connected to high voltage power supplies, with the electrodes corresponding to the first nozzle set being connected to a power supply of opposite potential than the electrodes corresponding the second nozzle set. Consequently, the spray issuing from the nozzle sets will be oppositely charged.

Abstract: This invention relates to a triboelectric projector of pulverulent coating product, comprising a channel for charging the coating product, a supply conduit connecting a source of coating product to said projector, a mixture of air and of coating product circulating in said conduit, an injector of air for dilution and/or acceleration of said mixture of air and coating product, characterized in that the outlet orifice of said injector is disposed on the path of said mixture of air and coating product in an inner chamber of the projector, downstream of the admission of said conduit in said projector and upstream of the inlet of the charging channel. The invention also relates to a process for controlling such a projector, consisting in measuring the charge obtained in the charging channel and in servo-controlling by this charge the instantaneous flowrate of air injected by the injector.

Abstract: An atomizer has a chamber holding a liquid containing particles of a desired material. Aerosol particles are formed by using an aspirating nozzle or ultrasonic vibrator and the aerosol particles are carried in a gas flow. The aerosol particles are treated by increasing the charge on the aerosol particles by contact with a high voltage electrode and the aerosol particles are passed through inertial separator stages to remove large aerosol particles from the flow so they are not discharged from the atomizer.

Abstract: A powder spray coating system includes a spray gun for spraying powder in a spray pattern onto a part. The spray gun includes an electrode connected to a power supply, the electrode charging powder as the powder is dispensed from the gun toward the part. A first current sensor measures gun current from the power supply to the electrode. An ABI probe or ion collector is mounted with the gun for collecting free ions produced by the electrode. The collector has a forward portion positioned near the spray pattern and spaced from the electrode. A second current sensor measures return current from the ion collector. A regulating assembly regulates the return current from the ion collecting device. A controller is connected to the first and second current sensors and to the regulating assembly for operating the regulating assembly in accordance with a predetermined setting representing the difference between the gun current and the return current.

Abstract: A plurality of linear elements or meshed elements are arranged in a powder paint transportation path in an electrostatic powder coating gun. The materials of the linear elements and meshed elements are capable of charging the powder paint by static electricity generated by friction between the powder paint and the elements.

Abstract: An electrospray apparatus incorporating the invention includes a capillary with an exit for ejecting a fluid, and an electrode positioned downstream from the exit. A gas source is used to establish a region of gas, at least immediately about the exit. A voltage supply creates a potential difference between the capillary exit and the electrode, the potential difference being sufficient to both establish a cone jet mode of operation at the exit of the capillary, to ionize the region of gas about the exit and create a current flow between the exit and the electrode. The current flow exhibits an increased value upon the gas becoming ionized, thus enabling detection of the establishment of a corona. This action creates a corona-assisted cone jet mode of electrospray operation which enables the fluid to disperse into highly uniform sized particles. The preferred gas is carbon dioxide.

Abstract: A rotary atomizing electrostatic coating apparatus having a rotating spray head, and a paint nozzle for feeding paint on the front surface of the spray head, in which the spray head is comprising a spray head main body made of an electrically insulating material, and a plurality of discharge electrodes having nearly band-form pattern extending outward approximately along the rear side shape of the spray head main body from the central side of the spray head main body with a mutual phase difference or extending symmetrically about the axis of rotation of the spray head main body. The plurality of discharge electrodes rotate together with the spray head main body, and the discharge current in the front side direction of the axis of rotation of the spray head is made uniform and increased, thereby enhancing the painting efficiency.

Abstract: A coating dispensing head includes a rotary dispensing device, a rotator for rotating the rotary dispensing device and a tachometer for generating a light signal in response to rotation of the rotator. The head includes a first connection for supplying the coating to the dispensing device, a second connection for supplying motive power to the rotator and a first optical fiber having a first end for receiving the light signal and a second end. At least one of the first and second connections includes first and second passageways terminating at respective first and second generally flat surfaces and connectors for holding the first and second surfaces against each other with the first and second passageways aligned so that the one of coating and motive power supplied to one of the first and second passageways flows into the other of the first and second passageways and thence to the one of the dispensing device and rotator.

Abstract: A spray gun for applying powder to coat a work piece uses triboelectric and optionally a corona discharge electrode to charge powder particles electrostatically. The gun communicates with a source of pressurized air through a handle with an air valve controlling flow of the air. Powder in a container in fluid communication with the air flow is fluidized and entrained when the valve is opened. A nozzle with an internal surface defining a passageway to an open end communicates with the powder container. The internal surface of the nozzle frictionally imparts a net electrical charge of a first polarity to part of the powder by frictional contact during spraying. A plurality of discrete tubes are disposed in the central passageway and impart a net electrical charge of a second polarity to another part of the powder due to frictional contact as that part flows around and through the tubes.

Abstract: A method and an apparatus for powder spraying can be used, for example, for electrostatic enameling. In order to achieve an easily regulatable high powder output rate, it is proposed to fluidize powder in a closed container, extract it in the region of the fluid bed and cause it to emerge through a nozzle on the container. The container is subdivided by a frit into a first chamber to which air is fed and a second chamber which contains the powder and out of which air is discharged through a valve. A powder output rate can be regulated by the regulation of air pressures.

Abstract: A device for dispensing a liquid for inhalation, which comprises an unshielded electrohydrodynamic comminution means (1), a means for supplying a liquid to the comminution means, a sharp discharge electrode (12) and, optionally, a means for charging the discharge electrode to a polarity opposite to that of the comminution means, wherein the discharge electrode is located so as to direct gaseous ions into the body of the comminuted liquid and thereby to fully or partially discharge the comminuted liquid.

Abstract: A spray gun type electrostatic paint coating machine which is capable of improving quality of coated surfaces, the coating machine including an air nozzle (8) and a paint nozzle (21) respectively provided at the fore end of a spray gun body (6). The spray gun body (6) and the air nozzle (8) are made of an electrically insulating material, while the paint nozzle (21) is made of a metallic material including a paint spouting orifice (21C) which is projected on the front side through the air nozzle (8). The paint spouting orifice (21C) is connected to ground through a paint supply passage (10) to serve as a grounding electrode. Sprayed paint particles are at the earth potential, so that they are less susceptible to influences of dielectric polarization and negatively charged quickly by the high negative voltage of the external electrode.

Abstract: An electrostatic painting system for painting an object or article under corona discharge. The system comprises a spray gun which is formed at its tip end with annular air ejection opening through which air is ejected under pressure to atomize liquid paint ejected from a paint ejection opening formed at the tip end of the spray gun. An annular wire netting-like negative electrode is fixedly disposed at the tip end of the spray gun and located coaxially around the air ejection opening. The electrode functions to form an electrostatic field and a corona discharge field between the electrode and the object to be painted and to provide electric charge to the atomized paint, upon a high negative voltage being applied to the electrode.

Abstract: Methods and apparatus are disclosed for spraying powder into the interior of welded hollow can bodies from a spray gun mounted to the welding arm of a can forming machine. The spray gun can either apply a stripe of highly charged powder on the welded seam areas of hollow can bodies, or can simultaneously apply a coating of powder having a first thickness on the longitudinally welded seam areas and a second thickness less than the first thickness on the remainder of the interior surface. Air is vented off from the powder flow being transported through the welding arm so that the powder to air ratio is increased. Air is introduced at the downstream end of the welding arm to provide a suction force to help draw the powder flow through the welding arm and to increase the velocity of the powder flow for better tribo charging of the powder in the gun and to improve spray pattern stability.

Abstract: For a rapid and simple assembly, the rotary atomizer of the coating arrangement described has a fastening pin (34) arranged on a valve unit (12). The fastening pin is inserted into a matching opening of a mounting flange (70) and is retained therein by a clamping device that exerts a force pressing the valve unit (12) against the flange (70). The atomizer is composed of individual modules (2,4,6,10,12) connected by screw connections and additionally comprises a rigid light guide rod for the transmission of optical rpm measuring signals, which remains in the valve unit (12) during disassembly of the atomizer.

Abstract: A device for delivering a finely divided coating product to a sprayer. The device includes a conveyer composed of a tube and a worm screw mounted in the tube for transporting the coating product, and a motor coupled to the worm screw for rotating the worm screw. The device is constructed for limiting the torque which must be transferred from the motor to the worm screw for rotating the worm screw.

Abstract: A system for atomizing and dispensing powder comprises a fluidized powder bed for entraining the powder fluidized in a bearing air stream, a dispenser, and a motor for rotating the dispenser. The dispenser has a somewhat bell-shaped interior. The motor has an output shaft having a first passageway extending lengthwise thereof. A feed tube extends through the first passageway. The fluidized powder is fed to an end of the feed tube passageway remote from the dispenser to be supplied through the feed tube to the interior as the motor rotates the dispenser. A diffuser is mounted within the interior. A discharge slot is defined between the dispenser and an edge of the diffuser. The feed tube is mounted so that it does not rotate with the output shaft. The diffuser includes a back side facing the interior and bounded by the edge. The back side includes a generally part-spherical concavity into which the fluidized powder is directed from the feed tube.

Abstract: In a triboelectric powder spray gun in which a charge is imparted to the powder triboelectrically by repeated impacts of the powder with contact surfaces, the charging effectiveness of the gun is enhanced by using an electrode to produce corona treatment of the contact surfaces. The corona treatments discharge the contact surfaces and eliminate the need for adjacent grounds with the powder flow path.

Abstract: Apparatus and methods for pumping a uniform flow of air entrained powder at low flow settings to a diffuser of an electrostatic spray gun which disperses the powder and cools the spray gun. A single or double stage pump with a bleed port design draws powder into the pump from a powder container when compressed air directed into the pump is above a predetermined pressure. In another embodiment, a pump delivers a constant velocity of air entrained powder to the spray gun.

Abstract: A process and apparatus for controlling high vegetative and brush growth along a narrow, continuous strip of land along the sides of a roadway or other right-of-way comprising preparing a dilute aqueous herbicidal solution, particulating said solution into coarse or large droplets and imparting an electrostatic charge to the droplets of herbicidal solution, and spraying the particulated and electrostatically charged droplets of said solution upon a narrow, continuous strip of land along the side of a roadway with minimal encroachment of the spray upon the environmental land adjacent said strip, and apparatus for effectively and accurately performing such operations.

Abstract: Apparatus for mounting and moving coating dispensers within the interior of a spray booth, and particularly the coating dispensers located above an object moving through the booth. A first embodiment comprises a dispenser housing having an aerodynamically shaped outer surface formed with a leading edge, a trailing edge and opposed generally curved sides. A second embodiment includes a dispenser housing an outer surface with a convexly curved leading edge, flat side walls and a flat bottom wall. A pair of support assemblies isolated from the booth interior mount the dispenser housings within the booth interior such that the leading edge of each dispenser housing faces the top of the spray booth and the trailing edge faces the objects moving through the booth. One or more coating dispensers are mounted at the trailing edge of the dispenser housings in a position to discharge coating material downwardly onto the object.

Abstract: A frictional electrification gun for use in electrostatic painting which can electrostatically charge power paint to a sufficient degree without the need of an elongated and twisted charging portion made up of nonconductive resin tubes. At the inlet of the charging portion made up of nonconductive resin tubes is provided a pre-charging portion for dispersing and charging powder paint. It has a nonconductive resin ring through which powder paint is fed swirling along its inner surface. The paint is thus sufficiently charged.

Abstract: In a method of electrostatic painting, the air to be conveyed towards the spraying nozzle (10) of a gun (9) together with the powdered paint, is enriched with at least one additive gaseous fluid consisting of at least one gas supplied from a feeding bottle (136, 137, 138, 139) and/or vapor obtained by submitting the air to bubbling through a working liquid (115). The additive fluid which has a greater electric conductivity than the air, causes an increase in the paint amount coated on the workpiece (11) in relation to the paint amount sprayed from the nozzle (10).

Abstract: A hand-held powder spray gun includes a wand type handle that extends from the top of the handle and away from the rear of the gun, which provides for ergonomic operation of the gun. The wand handle can be converted to a pistol handle by removal of the handle from the gun body. The parts of the wand handle and the pistol handle are interchangeable to facilitate conversion and repair. The wand handle can be used with a diffuser having hose connections extending from the rear of the spray gun to make the gun easier to operate when held from above. A diffuser having hose connections at the bottom is also provided for use with a pistol type handle.

Abstract: An apparatus for mounting and moving coating dispensers within the interior of a spray booth, and particularly the coating dispensers located above an object moving through the booth, comprises a dispenser housing having an aerodynamically shaped outer surface formed with a leading edge, a trailing edge and opposed generally curved sides. A pair of support assemblies isolated from the booth interior mount the dispenser housing in the path of a downward flow of air within the booth interior within which oversprayed coating material is entrained for collection such that the leading edge of the dispenser housing faces the top or ceiling of the spray booth and its trailing edge faces the objects moving through the booth. One or more coating dispensers are mounted at the trailing edge of the dispenser housing in a position to discharge powder coating material downwardly onto the object, such as the hood, roof and trunk of a vehicle body.

Abstract: A portable electrostatic liquid sprayer including a small internal combustion engine with a magneto-type ignition system providing a high voltage source to inductively charge atomized droplets being sprayed onto crops or plants. A conductive voltage tap is coupled between a spark plug boot from the magneto and the high voltage terminal of a spark plug for access to the high voltage provided by the magneto. A wire is connected to the voltage tap and routed and connected to an RC filter and rectifier circuit mounted in the sprayer head. A ground wire is electrically coupled to the chassis of the engine and also routed and connected to the RC filter and rectifier circuit. An electrode mounted near the outlet of the sprayer head and connected to the RC filter and rectifier circuit establishes an electrostatic field within the sprayer head effective to inductively charge the atomized droplets as they are being ejected from the sprayer head.

Abstract: An electrostatic sprayer installation for powder coating product comprises a plurality of powder sprayers and a plurality of powder storage tanks each adapted to contain powder of a specific color. Connecting ends of a plurality of suction tubes for each storage tank are disposed side by side on a connecting socket of the storage tank. A connecting block is provided with powder suction devices each establishing communication between a hose connected to a sprayer or a group of sprayers and one of the suction tubes. The connecting block is removable so that it can be mounted on the connecting socket of a selected storage tank. An air blower station has a connecting socket analogous to that of a storage tank and comprises air ejector orifices disposed to be connected to the suction devices.

Abstract: The invention relates to a fluid distribution device in the form of a sprayer. A preferred embodiment of the sprayer uses a rotating fluid conduit which makes use of centrifugal force to break up fluid emerging from the conduit into fine droplets. Air flow though the preferred embodiment may shear the fluid droplets and assist in carrying them to the desired target. An apparatus for placing an electrostatic charge on the droplets may also be used.

Abstract: An electrostatic spray apparatus comprises a source of electrostatically charged liquid connected to an annular nozzle which discharges a hollow tube of electrostatically charged liquid, a source of atomizing air under pressure, an annular atomizing air discharge nozzle surrounding the liquid discharge nozzle, and an annular swirl chamber for the atomizing air. A plurality of apertures connect the source of air to the swirl chamber, the apertures being oriented at an angle to the radial direction to initiate a substantially tangential swirling flow of air in the chamber and being disposed to allow air to pass radially outwardly into the chamber. The chamber is defined by walls which tend to converge in an axial direction from the plurality of apertures towards the air discharge nozzle.

Abstract: The present invention is directed to methods and apparatus for spraying liquid compositions by airless spray techniques which avoid fishtail spray patterns and desirably obtain feathered spray patterns through use of spraying coating formulations which contain supercritical fluid.

Abstract: An apparatus for charging droplets of a volatile liquid and for directing the charged droplets against an oppositely-charged member. The apparatus comprises a source of a mist of uniform fine droplets of a volatile liquid and a droplet-charging zone associated with said source for applying a charge to the droplets in the mist. The droplet-charging zone comprises a source of ionized air ions for imparting the charge and a predetermined velocity to the droplets. A discharge conduit is provided having a discharge nozzle for directing the charged droplets against the surface of a member for attraction and deposit onto areas thereof charged to an opposite polarity. Preferably, the droplet-charging zone is associated with an air ionization zone comprising a source of air, a means for ionizing the air, and a means for directing the ionized air at a predetermined velocity into the droplet-charging zone to apply the charge to the droplets.

Abstract: An apparatus is disclosed suitable for electrostatic spraying from fixed wing aircraft. The apparatus includes a linear electrostatic spraying nozzle 2 and electrodes 4 placed near the nozzle's spraying edge to intensify the electric field strength at the spraying edge sufficiently to produce ligaments of the liquid to be sprayed from the spraying edge. In order that the airstream due to the aircraft's movement does not destroy the ligamets, the sprayhead and the electrodes are positioned so that part of the airstream flows between them. The spray head and the electrodes are so shaped and positioned that when directed to spray in substantially the same direction as the airstream, a turbulence free wake is left in the region of the ligaments.

Abstract: A spray gun with electrokinetic charging of powdered material for the purpose of electrostatically coating workpieces with a powder coating. As the powder flows pneumatically through a channel of insulation material in the form of an annular gap, the plastic powder to be applied is charged by superimposition of triboelectric effects with ionization processes initiated by these effects at a passive ionizer electrode, and completed by friction against a semiconductive insert within the annular gap. Thus, the effective area of the electrostatic induction ionizer is expanded, the charge on the powder is increased and spark-like sliding discharges in the flow channels as well as dielectric breakdowns of the channel wall are prevented.

Abstract: 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 non-conductive shaft rotatably mounts a non-conductive turbine and rotary atomizer bell assembly.

Abstract: A hand held powder spray gun is disclosed. The spray gun includes a casing enclosing a plurality of helical charging ducts mounted on parallel cores. The ducts receive powder from a diffusor mounted in a depending gun handle and discharge charged powder towards a nozzle mounted at one end of the casing.

Abstract: An electrostatic spray head is charged with high voltage from a high voltage source. As a liquid to be sprayed is supplied to the spray head, the liquid is atomized predominately due to the high voltage. The spray head is located within or closely adjacent to a gas stream flowing along a path which extends in the spraying direction, so that at least some of the atomized liquid becomes entrained in the gas stream. The gas stream has a lower velocity region and a high velocity region, of which the lower velocity region is transversally closer to the spray head.

Abstract: An electrostatic powder spray gun comprises a powder cup and is constructed such that the powder cup comprises a removable cover which is secured to the pistol tube of the gun in an easily-detachable manner, whereby a conveying tube and an air tube extend through the cover and are held thereat. The air tube projects beyond the cover and, given the cover secured to the pistol tube, projects into a spring-loaded discharge valve of the compressed air feed line and thereby holds the same in the open position against spring pressure. Given the cover secured to the pistol tube, the orifice of a powder channel extending in the pistol tube is constructed as a connection for a powder feed line leading from a remote powder preparation system.

Abstract: A power spray system for applying particulate powder material to a substrate includes a volumetric or gravimetric dry material feeding device having an outlet connected to a manifold formed with an internal cavity and a plurality of passageways communicating with the internal cavity. A highly accurately metered quantity of powder is transmitted into the internal cavity of the manifold, which is either applied to the substrate or recirculated back to the powder source. An air amplifier connected to one of the passageways is operable to draw ambient air through a vent passageway into the internal cavity of the manifold to form a stream of air-entrained powder. The powder stream is then drawn out of the internal cavity of the manifold by the air amplifier into a spray gun for discharge onto the substrate.

Abstract: An inductor nozzle assembly for use with an air blast sprayer of the type having a tank holding waterborne pesticides, delivery lines connected to the tank and an air blast fan mounted in close proximity to the delivery lines, includes a spray nozzle mounted to the delivery lines which is disposed in the hollow interior of a conical-shaped housing mounted thereto. The housing is formed with an enlarged entrance opening, and a reduced diameter discharge opening which mounts an inductor ring charged with high electrical potential. A high velocity stream of air produced by the air blast fan is directed into the housing through its entrance opening where the air stream is accelerated by the conical shape of the housing toward its discharge opening.

Abstract: A versatile spraying gun includes main tool and several attachment tools any one of which can be inserted in the main tool. Each attachment tool is designed to atomize powder particles that are to be sprayed on an article in accordance with a specific spraying method and atomization principle and method. The main common tool is comprised primarily of a body that defines a powder delivery channel and a coupling piece and discharge electrode located upstream in the delivery channel. The attachment tools have a flow guide member disposed axially within the delivery channel and an attachment piece for attaching the attachment tool to the coupling piece of the main tool. In some attachment tools, the flow guide member also houses a high voltage circuit and appropriate electrodes needed for electrostatic charging of the powder which passes through an electrical field set up between the electrodes.

Abstract: A powder spray gun for applying particulate powder material onto a surface includes a gun body having a venturi transfer pump which receives air-entrained particulate powder material from a supply conduit and distributes the powder for discharge into a discharge conduit connected to the gun body. A spray head formed with a powder discharge slot is mounted to said discharge conduit. The discharge conduit is formed with a bend, preferably of about 90.degree., to concentrate the powder material along an outer wall formed by the bend for delivery in a concentrated stream to the spray head. A deflector is preferably mounted within the discharge conduit to direct the concentrated powder stream into the spray head in a predetermined manner. The powder discharge slot, which has a predetermined width and is formed by angled side walls meeting at an apex, receives the concentrated powder stream from the discharge conduit and sprays the powder in a wide, uniform spray pattern onto a surface.

Abstract: A spray gun is designed for mounting on the end of a robot arm. The construction of the gun is provided such that nearly all of the main components with the exception of the spray head itself are located in a main body to which is mounted a pivotal spray head assembly which may pivot approximately 90.degree. to either side of the normal straight-ahead position. The power supply and power generating units are located in the main body. The electrostatic power supply connection to the spray head enters the spray head shaft on the opposite side from the fluid supply entry. The fluid control valve may be located in the spray head shaft.

Abstract: An electrostatic powder spray gun is provided with an arcuate nozzle tube forming a curved passage between an inlet and outlet orifice. A mixture of powder particles and a carrier gas injected into the inlet orifice is subjected to a swirling motion prior to exiting the outlet orifice. This swirling motion is caused by helical grooves cut into the inside surface of the arcuate tube adjacent to the outlet orifice. An electrode imparts an electrical charge to the particles as they exit from the nozzle tube.

Abstract: A method of and apparatus are disclosed for spraying powder, particularly for the coating of articles, by introducing a spray gas into the powder as the latter is expelled from a spray opening. An additional gas is injected into the stream of powder upstream of the point where the spray gas is introduced, in such a manner as to exert a cyclone effect on the stream of powder, force the powder radially outward and simultaneously drive it in the direction of flow of the powder.

Abstract: This invention relates to the fabrication of an improved electrode for an electrostatic atomizing device. The electrode consists of metal oxide-metal composite fragments dispersed and bonded in a metallic matrix. The composite fragments contain submicron metallic fibers uniformally arrayed in a nonconducting (insulating) matrix. The electrostatic atomizing device includes a cell having a chamber disposed therein, a discharge spray means in communication with the cell, at least two electrodes disposed in the chamber and being in liquid contact with the liquid in the chamber, the liquid in the chamber being transported to the discharge spray means and atomized into droplets, and a mechanism for generating by means of the electrodes, a charge through the liquid within the chamber, wherein the charge enamating from the improved electrode is sufficient to generate free excess charge in the liquid within the chamber, and the liquid is atomized into droplets.

Abstract: A powder sprayer to be charged electrostatically, comprising a plurality of elongated, curved charging ducts made of an electrically non-conducting material and coated with an electrically-conducting layer over part of their length and connected via a lead to earth or to a voltage source, so that when the sprayer is used the powder material is charged by close contact with the internal walls of the ducts as it passes through the charging ducts. The ducts are curved around to form at least one loop and/or undulation with their longitudinal center plane extending substantially in the supply direction of the powder.

Abstract: This invention relates to an electrostatic atomizing device and a process thereof for the formation of electrostatically charged droplets having an average diameter of less than about 1 millimeter for a liquid having a low conductivity wherein the device includes a cell having a chamber disposed therein, a discharge spray means in communication with the cell, the liquid in the chamber being transported to the discharge spray means and atomized into droplets, and a mechanism for passing a charge through the liquid within the chamber, wherein the charge is sufficient to generate free excess charge in the liquid within the chamber.