Abstract: A paint spraying unit for generating a shaped paint jet, including a paint nozzle positioned in a gap, wherein the paint nozzle includes a needle with a needle head that deviates from a rotationally symmetrical cross sectional design and a paint outlet opening that deviates from a rotationally symmetrical cross sectional design. The needle head is displaceable in relation to the paint outlet opening along a longitudinal axis of the needle for controlling a needle valve formed by the paint outlet opening and the needle head. The needle head, with the paint nozzle in a closed position with reference to the longitudinal axis, closes the paint outlet opening in a positive locking manner. In this connection, the needle head and/or the paint outlet opening is/are formed by a material with elastic properties at least in a surface region with which the two components come in contact.

Abstract: Systems and methods that provide or restore a coating to a component are provided. The systems and methods utilized an atomizing spray device. A gas and a slurry that comprises fluid and ceramic particles are supplied to the atomizing spray device. The slurry and gas are discharged from the spray device to form two-phase droplets. The fluid within the droplets evaporates to prevent the fluid from becoming part of the coating as the droplets traverse through the air and prior to impacting the surface of the component.

Abstract: A shaping air spurting member (9) is formed in a tubular shape by using a conductive material, and is arranged on an outer peripheral side of a rotary atomizing head (4) in a state where a front end thereof is positioned in an intermediate section of the rotary atomizing head (4) in a length direction. The shaping air spurting member (9) has a front surface section (9D) that is provided with many numbers of air spurting holes (10, 12) for spurting shaping air toward paint particles sprayed from the rotary atomizing head (4). In addition, a shield member (14) composed of an annular body extending radially is provided on an outer diameter side of the front surface section (9D) in the shaping air spurting member (9) to shield electric flux lines traveling toward the rotary atomizing head (4) from each of electrodes (6C) in an external electrode member (6).

Abstract: Provided is an electrostatic coating method using a conductor such as a metal or a conductive resin as a coating target surface 21, the method including coating the coating target surface 21 with a charged paint by ejecting the charged paint from a spray gun 1 in a state where generation of an electrostatic field between a spray gun 1 and the coating target surface 21 is prevented and generation of free ions is prevented.

Abstract: An air cap for a spray gun, in particular a paint spray gun, having at least one central opening, which is delimited by a mouth, and two horns, each having at least one inner and one outer horn air duct and one inner and one outer horn air opening. The spacing between the front end of the central opening and an axis which perpendicularly intersects the central axis of the central opening and runs through the center of an inner horn air opening is between 0.6 mm and 2.6 mm. The spray pattern generated by the air cap has a longer core region and a steeper transition of the layer thickness between the external region and the core region, compared to conventional air caps leading to improvement in coating quality. A nozzle assembly and a spray gun, in particular a paint spray gun, can have an air cap having the above properties.

Abstract: Systems and methods that provide or restore a coating to a component are provided. The systems and methods utilized an atomizing spray device. A slurry that comprises a fluid and ceramic particles, and a gas are supplied to the atomizing spray device. The slurry and gas are discharged from the spray device to form two-phase droplets. The fluid within the droplets evaporates to prevent the fluid from becoming part of the coating as the droplets traverse through the air and prior to impacting the surface of the component.

Abstract: The invention relates to a painting booth for coating components, particularly for painting motor vehicle body components, with a booth wall (10) and a coating agent line (1), which runs from the exterior of the booth through the booth wall (10) into the interior of the booth. The invention proposes that the coating agent line (1) has an electrically conductive and axially running potential-compensating element (15) inside the line for electrically connecting the coating agent inside the line to an electrical reference potential, said potential-compensating element (15) extending from the exterior of the booth through the booth wall (10), so that the free end of the potential-compensating element (15) is inside the booth.

Abstract: An attachment to be employed with any spray device is disclosed. The attachment includes four vanes which are radially attached to an air hub with a central aperture, the central aperture adapted to receive the front portion of the spray device therethrough which when activated dispenses an atomizable substance in a pattern toward a workpiece. At the distal end of each of the four vanes, the vane is angled forward such that it generally points toward the workpiece. At the terminal end of each vane is a plurality of compressed air exit apertures. A compressed air source is attached to the air hub which guides the air through air conduits interiorly disposed within each of the vanes, where the compressed air is forced to exit each of the compressed air exit apertures forming an a second pattern which surrounds the atomizable substance pattern, and further boosts or pushes the atomizable substance onto the workpiece.

Abstract: An electrostatic spray system, comprising a hand held device having an inlet and an outlet. The hand held device includes a charging device for producing a high voltage charging field and a spray nozzle having an outlet, the outlet being disposed within the charging field. The system further includes an air movement system disposed within the hand held device, the air movement system configured to produce an airflow around the spray nozzle and through the high voltage charging field to create a directionally controllable electrostatic charged mist existing the hand held device at low velocities.

Abstract: A sachet (1) having walls of flexible material is disclosed. The walls are joined so as to form an impermeable seal, thereby defining a cavity within the sachet (1). A conduit (2) passing through the seal and having inner and outer ends is disposed with the inner end within the cavity and the outer end outside the sachet (1) such that the cavity is in fluid communication, via the conduit, with the outside of the sachet. The cavity contains a volume of liquid (8) in use, and the conduit (2) is adapted to prevent the liquid (8) flowing from the cavity without the application of an additional stimulus, irrespective of the orientation of the sachet (1).

Abstract: A compressed air throttle apparatus has at least one throttle valve adjusted by an electric motor, and an electric circuit fitted with contacting elements to alternatively interrupt and close the electric circuit in relation to the throttle valve settings. This throttle apparatus preferably is applicable to a compressed air path of powder spraycoating equipment.

Abstract: An electrostatic spray charging nozzle designed for optimum charge level over a wide range of liquid and air flow rates. The electrostatic spray charging nozzle includes a nozzle cap having an outlet, a nozzle body having a first bore, and a fluid tip assembly extending at least partially through the first bore. The fluid tip assembly further includes a liquid inlet adapted to be connected to a source of liquid, and a liquid outlet adapted to dispense the liquid through the outlet of the nozzle body. The electrostatic spray charging nozzle further includes an adjustment mechanism operable to move the fluid tip assembly within the first bore so as to adjust a longitudinal distance between the liquid outlet of the fluid tip assembly and the outlet of the nozzle cap.

Abstract: An electrostatic spraying device has a removable cartridge with a reservoir containing a volume of liquid compositions to be electrically sprayed. The device includes a nozzle for dispensing the liquid and an emitter electrode disposed adjacent to the nozzle for charging the liquid composition just being dispensed from the nozzle. A field electrode surrounds the reservoir in order to charge the liquid composition within the reservoir, thereby avoiding an occurrence of electric current which would deteriorate the composition remaining in the reservoir. The reservoir is at least partially made of deformable material such that the reservoir is capable of receiving pressure to deform and thus supply the liquid composition out of the reservoir. Thus, the reservoir can be designed into a simple and compact structure, thereby providing an increased liquid containing volume in relation to the bulk of the removable cartridge.

Abstract: An electrostatic spraying device has a capability of confirming that the device is ready for making an electrostatic spraying of the liquid composition on a user's skin. The device includes a nozzle and a pump for dispensing the liquid composition out through the nozzle. An emitter electrode is disposed to electrostatically charge the liquid composition being dispensed for making the electrostatic spraying. The device is provided with a power switch and a selector for selection between a spraying mode and a dripping mode. In the dripping mode, the pump is alone actuated to dispense the liquid composition absent electrostatic charge. In the spraying mode, both of the pump and the emitter electrode are activated to make the electrostatic spraying. Thus, the user can be easy to drip the liquid composition by simply manipulating the selector prior to initiating the electrostatic spraying.

Abstract: An electrostatic spraying device having a removable cartridge with a reservoir containing a volume of liquid compositions to be electrically sprayed on a user's skin. The device includes a nozzle for dispensing the liquid as well as an emitter electrode disposed adjacent to the nozzle for charging the liquid composition just being dispensed from the nozzle. A field electrode surrounds the reservoir in order to charge the liquid composition within the reservoir, thereby avoiding an occurrence of electric current which would otherwise flow in the liquid composition and would deteriorate the composition remaining in the reservoir. The reservoir is devoid of the field electrode, and therefor can be designed into a simple and compact structure without being restricted by the field electrode, assuring to have an enhanced liquid containing volume in relation to the bulk of the removable cartridge.

Abstract: A spray gun for electrostatic painting in which an external electrode sustaining a high voltage can be fixed/removed while sustaining insulation from a spray unit on the ground potential side by limiting current supply to paint appropriately when electrostatic painting is performed using conductive paint, e.g. water based paint, and safety and handling performance are enhanced while ensuring the painting efficiency as the spray gun for electrostatic painting. On the outside of the spray gun (1) having the spray unit (5) at the forward end thereof, the external electrode (7) having an electrode projecting from the forward end part thereof is provided removably at the part (13) of the gun body being connected with the electrode while being separated from the paint passage such that it can be replaced readily.

Abstract: A method and apparatus to improve the atomization of liquid and the efficiency of depositing liquid particles onto target objects, or to coat the target object with a thin film of liquid, to reduce the risk of high-voltage electrical shock, and to reduce the weight of an electrostatic spray system has been developed by inducing electrostatic charges onto the atomized liquid particles sprayed from a grounded metal nozzle.

Abstract: A powder coating gun with an internal fan and a quick-change powder cartridge. Pressurized air generated by the fan entrains the powder coating material from the powder cartridge and the entrained powder coating material is charged in the ionizing field created by an emitter. The replaceable cartridge contains an inlet line and an outlet line oriented in a manner that allows the powder gun to be positioned in different angles and orientations with minimal risk of a powder spill from the powder coating gun. The powder cartridge contains a lid for supporting an inlet line and a body part constructed of clear or translucent material that allows the user to easily view the color of the powder. An electric power supply is used to power the fan and the emitter. A trigger is present in the handle of the powder coating gun and both controls the speed of the fan and enables the charge to the emitter.

Abstract: A modular spray gun that can be configured and built to operate using a selectable spray process. The modular spray gun includes a gun body, an extension and a selectable spray atomizing component. The basic gun body and extension are used to configure a spray gun that can operate as an air spray gun, an airless spray gun, an AAA gun or an HVLP spray gun. The modular extension can be selected to allow circulating or non-circulating operation. The modular extension also permits a variety of spray nozzle assemblies to be mounted thereon depending on the selected spray process to be used with the specific gun. The modular gun body allows selective connection of an atomizing air supply and additional components specific to a particular spray process. An indicator device and/or a relief valve is provided for spray guns using an HVLP spray process to provide an indication that the spray gun is in compliance with the maximum nozzle air pressure limit, usually less than 10 psi.

Abstract: A coating material dispensing device includes a port adapted to be coupled to a source of coating material, an actuator for controlling a flow of compressed gas through the dispensing device, and a valve coupled to the actuator to be controlled by the actuator. The valve includes a valve housing, a valve closure member, and a valve seat. The valve closure member is movable in the housing under the control of the actuator between a closed position against the valve seat and an open position away from the valve seat. An inlet port is provided into the housing. The inlet port is oriented on a first side of the valve seat. The inlet port is adapted to be coupled to a source of the compressed gas. An outlet port is provided on the second side of the valve seat.

Abstract: An electrostatic method for increasing the transfer efficiency of spray finishing using lower voltages than are normally required and used with electrostatic spraying. The positioning and construction of ground electrodes (16) behind the air cap (18) helps ensure a clean operation.

Abstract: A high-speed rotary atomizer for applying powder coating comprises in a known manner a housing (1), in which a motor (13) is accommodated. The motor (13) rotates a bell-shaped plate (16) which is disposed at the front of the housing (1). At least one powder supply duct (28, 29, 22, 23, 24, 25, 11, 12, 9, 10) leads through the housing and opens at the front of the housing (1). Its cross section can therefore be kept very large, thereby increasing the powder output of the high-speed rotary atomizer. This also enables a plurality of powder supply ducts (28, 29, 22, 23, 24, 25, 11, 12, 9, 10) to be laid, which in turn results in a higher powder throughput and improved homogeneity of the powder cloud which is produced.

Abstract: A dust collector for collecting dust, in which the rarefaction of a dielectric at the rear part of electric field forming apparatus is prevented, whereby the collecting efficiency can be increased. The dust collector includes a charging device for charging a substance to be collected, such as dust and mist, contained in a gas; a sprayer device for spraying a dielectric on the substance to be collected which is charged by the charging device; an electric field forming device, having first and second electrodes and which form a direct current electric field and dielectrically polarize the dielectric sprayed by the spray device; and a dielectric collecting device for collecting the dielectric which has arrested the substance to be collected. The spray device includes grounding device and for electrically grounding the dielectric before being sprayed to let a charge of the dielectric escape.

Abstract: A dust collector for collecting dust, in which the rarefaction of a dielectric at the rear part of electric field forming apparatus is prevented, whereby the collecting efficiency can be increased. The dust collector includes a charging device (1) for charging a substance (9) to be collected, such as dust and mist, contained in a gas; a sprayer device (2) for spraying a dielectric (10) on the substance (9) to be collected which is charged by the charging device (1); an electric field forming device (3), having first and second electrodes (11) and (12) which form a direct current electric field and dielectrically polarize the dielectric (10) sprayed by the spray device (2); and a dielectric collecting device (16) for collecting the dielectric (10) which has arrested the substance (9) to be collected. The spray device (2) includes grounding device (17) and (18) for electrically grounding the dielectric (10) before being sprayed to let a charge of the dielectric (10) escape.

Abstract: A modular spray gun that can be configured and built to operate using a selectable spray process. The modular spray gun includes a gun body, an extension and a selectable spray atomizing component. The basic gun body and extension are used to configure a spray gun that can operate as an air spray gun, an airless spray gun, an AAA gun or an HVLP spray gun. The modular extension can be selected to allow circulating or non-circulating operation. The modular extension also permits a variety of spray nozzle assemblies to be mounted thereon depending on the selected spray process to be used with the specific gun. The modular gun body allows selective connection of an atomizing air supply and additional components specific to a particular spray process. An indicator device and/or a relief valve is provided for spray guns using an HVLP spray process to provide an indication that the spray gun is in compliance with the maximum nozzle air pressure limit, usually less than 10 psi.

Abstract: A coating dispensing apparatus includes an atomizer and a housing for the atomizer. The housing includes a forward end defining an opening through which coating material dispensed by the atomizer is discharged. The forward end includes an inner portion and an outer portion. One of the inner portion and the outer portion includes a first surface. The other of the inner and outer portions includes a second surface. At least one of the first and second surfaces includes grooves which extend to the forward end and terminate around the opening. Compressed gas supplied to the grooves remote from the opening flows toward the forward end and exits from the grooves around the opening.

Abstract: A rotary atomizing head type coating machine which is arranged to prevent occurrence of spark discharges, including a rotational shaft (9) which is formed of an insulating material, a rotary atomizing head (11) which is likewise formed of an insulating material and mounted on a fore end portion of the rotational shaft (9). An on-head semi-conductive coat film (14) is formed on outer peripheral surfaces of the rotary atomizing head (11). On the other hand, a first arcuate coat film (16) is formed on a first limiter ring (15) which is provided on a motor body (6), and a second arcuate coat film (18) is formed on a second limiter ring (17) which is provided on the rotary atomizing head (11). Further, a power supply semi-conductive coat film (19) is formed on and around outer peripheral surfaces of the rotational shaft (9) between the arcuate coat films (16) and (18).

Abstract: An electrostatic spray module for applying agricultural liquids such as a pesticide to crops where, externally to the spray module the number of connections is reduced to three, one for the liquid pesticide, one for compressed air and one for a low voltage signal. Internally to the spray module, the low voltage is converted to a high voltage signal, which is, along with the pesticide and the compressed air delivered to one or more electrostatic spray nozzles using only two electrically conductive pipes, a gas delivery pipe and a liquid delivery pipe. The nozzles fit into the gas delivery pipe and draw the compressed air through gas channel openings in the side of the nozzles. The gas delivery pipe doubles as the means to delivery the high voltage signal to the nozzles. Each nozzle has a liquid feed from the liquid delivery pipe, which carries ground voltage, maintaining the liquid at ground voltage. The grounded liquid merges with the compressed air in the nozzles to form an atomized liquid.

Abstract: A rotary atomizing head type coating machine which is capable of washing deposited paint from fore end portions of outer peripheral surface of a bell cup. Thinner passages are provided on the bell cup to communicate a paint reservoir with the outer peripheral surface of the bell cup. Thinner which flows out onto the outer peripheral surface of the bell cup through the thinner passages is guided toward the marginal releasing edge of the bell cup. To this end, assist air is spurted out through assist air outlet holes which are provided in the fore end face of a shaping air ring at positions radially on the inner side of shaping air outlet holes. Accordingly, at the time of a washing operation, the thinner which has come out onto the outer peripheral surface of the bell cup is forcibly pushed on the outer peripheral surface by the actions of assist air and shaping air as the thinner is guided toward the fore end of the bell cup to wash away deposited paint therefrom.

Abstract: A flat panel display spacer metering apparatus comprises a motor-driven rotatable disc, having a plurality of cavities distributed around a first surface of the disc. As the disc is rotated, its cavities are filled with spacers from a storage and fill device, configured as a hollow cylinder installed in a bore of a metering block. To facilitate transfer of spacer elements stored in the storage cylinder into cavities in the disc, an axially biased plunger continuously pushes the spacer elements against the first surface of the disc. As a result, whenever rotation of the disc exposes one or more of its cavities to the open end of the cylinder, spacers are forced into and fill the cavities. As the disc is further rotated and successive ones of its cavities are filled with spacers, the filled cavities are brought into alignment with a spacer element ejection head. The ejection head continuously directs a fluid, such as dry nitrogen gas against the cavity-containing surface of the disc.

Abstract: Induction charging apparatus for HVLP spray guns and air-assisted airless spray guns includes an air cap having a central orifice for receiving a spray gun nozzle. The cap includes one or more charging electrodes adjacent the orifice and carrying a voltage sufficiently large to induce on the spray droplets charges of a polarity opposite to that on the electrodes. A rotatable electrical connector enables the cap to rotate 360.degree. while maintaining electrical connections between the electrodes and a power supply. The spray gun nozzle is an airless nozzle receiving liquid at a pressure of about 1,000 psi and having a spray tip from which liquid is sprayed along a flow path coaxial with the electrodes. Air at less than about 10 psi is directed along the flow path to assist in the atomization of the liquid from the airless nozzle.

Abstract: An improved powder particle supply and transport apparatus and method include a hopper filled with powder particles, an ejection chamber spaced from the hopper and a movable conveying member with a plurality of cavities formed therein. During operation, the conveying member moves the cavities between the hopper and the chamber, and the cavities are filled with powder particles at the hopper and emptied of powder particles at the chamber. An ejector nozzle sprays pressurized air into the chamber toward an aligned outlet, thereby to: 1) create negative pressure in the chamber to draw powder particles from the cavities as the cavities are moved therethrough; and 2) transport powder particles through the outlet to a spray gun. Additional structure may be used to assure complete powder filling of the cavities at the hopper and/or complete powder emptying of the cavities in the chamber.

Abstract: A particle spray apparatus includes a spray gun having a deflector connected with a housing assembly. An electrode arrangement extends from the housing assembly into the deflector and is exposed to the flow of air with particles entrained therein to electrostatically charge the particles. The electrode arrangement is exposed to a flow of fluid to remove contaminants which may accumulate around components of the electrode arrangement. Accumulation of particles on an end surface of the deflector is discouraged by a flow of fluid from a chamber in the deflector through a porous member. The flow of fluid from the chamber is also conducted through a porous electrode sheet which extends along the porous member. Due to the relatively high voltage conducted through the electrode arrangement, an arc may tend to form in a passage along which fluid is conducted to the electrode arrangement. To prevent this from occurring, the passage through which fluid is conducted to the electrode arrangement is relatively long.

Abstract: An electrostatic powder-coating gun is provided which comprises a powder duct which is connected to a supply conduit for a powder-air-mixture and arranged along the longitudinal axis of the gun barrel and having an open mouth towards the work to be coated, a high-voltage generator, an electrode supporting tube extending through the powder duct in axial direction thereof, and a high-voltage electrode located on the supporting tube and protruding beyond the mouth of the powder duct towards the work. The high-voltage generator and the powder duct are disposed in series along the longitudinal axis of the powder tube in such a way that the powder duct is adjacent the muzzle of the gun barrel. The powder duct is comprised of a toroidal duct and an annular channel extending therefrom and opening to the outside.

Abstract: Induction charging apparatus for HVLP spray guns includes an air cap having a central fluid exit orifice for receiving the spray gun nozzle. The cap includes one or more charging electrodes surrounding the orifice and carrying a voltage sufficiently large to induce on the spray droplets charges of a polarity opposite to that on the electrodes. The cap includes a rotatable electrical connector to enable the cap to rotate 360.degree., while maintaining electrical connections between the electrodes and a power supply.

Abstract: A hand held electrostatic powdered paint spray gun that has a trigger which allows the user to vary the voltage and the paint density supplied to the gun. The trigger is coupled to a potentiometer that provides an output voltage to circuits that control the flowrate of the paint powder and a voltage supply to the paint powder.

Abstract: An adapter for converting spray guns to electrostatic or induction charging includes a housing mountable on a spray gun. A high voltage power source is contained in the housing and is connected to an electrode assembly mounted on the front of the housing. The electrode assembly includes four electrodes which extend in front of the spray gun nozzle and air cap and are spaced symmetrically around the spray axis. The nozzle is electrically grounded, while the electrodes carry a voltage in the range of 3-15 kV, to produce in the spray path from the nozzle an electrostatic field which produces electrical charges on the sprayed particles. When conductive liquids are sprayed, the particles are charged by induction at relatively low electrostatic field gradients, while nonconductive liquids require high electrostatic field gradients which produce corona effects. These corona effects are enhanced by the provision of a corona needle mounted on the nozzle at the spray axis.

Abstract: Electrostatically charged liquid such as water is supplied via rotating structure to impinge on a baffle. The latter deflects the charged liquid onto a rotating insulative, frusto-conical surface on which the charged liquid forms a film which flows forwardly to an annular edge. Gas such as air, sweeping past the edge, impacts the layer arriving at the edge and produces fine charged droplets of the liquid, forming a fog. This charged fog is usable for suppressing dust particles in the air.

Abstract: The nozzle assembly of an electrostatic spray gun has an adapter which is made of an electrically insulating material and has a front surface facing in the direction of propagation of material issuing from the orifice of the nozzle. The adapter has a frustoconical extension which surrounds the orifice and whose external surface defines with the front surface of the adapter an annular space for the tips of electrodes which ionize air flowing toward the spray of material that issues from the orifice. The locations of the tips of electrodes (preferably very close to the front surface of the adapter) and the inclination of the external surface of the frustoconical extension determine the location of contact of ionized air with the spray. The tips of the electrodes are shielded from mechanical damage by being located in the annular space.

Abstract: An electrostatic powder spray gun comprises a powder channel for a powder-air mixture to be sprayed, the powder channel extending through a pistol tube and discharging axially forward at the forward end of the gun through an annular opening which is coaxial with the longitudinal axis of the pistol tube. An auxiliary air line extends through the pistol tube and discharges at the forward end and is constructed in such a manner that the auxiliary air line discharges axially forward as an annular opening coaxial with the annular powder opening, in particular radially and slightly in front of the annular powder opening. An air deflecting member is arranged in front of the auxiliary air annular opening and is seated at the free end of a rod which extends centrally through the pistol tube and is axially displaceable therein. The rod is mechanically coupled to the trigger of the spray gun so that the air deflecting member can be adjusted from the trigger.

Abstract: An apparatus for the electro-kinetic charging of powder-like materials having a pair of supply channels, an input zone for each channel, one for the powder dispersed in a gas flow and one for another gas flow and which are shaped as dual annular nozzles with a pipe-shaped separating wall therebetween acting as an electrostatic ionizing electrode and made from an electrically semiconductive material having anti-sticking properties and, wherein the adjoining flow channel is formed as an annular channel by a pipe from an insulating material, and a centrally arranged rod, wherein the ratio between rod and pipe diameters is on the range from 0.75 to 0.9.

Abstract: A stream of carrier gas with powder particles is introduced at the feeding nd (2) of a powder pipe (1) in the direction of arrow (3) for coating workpieces. The material of the coating powder, of the powder pipe (1) and of displacement bodies (21, 22) built in the latter have different dielectric constants. At a certain distance from the outlet end (5) is mounted a charging device (12) provided with boosting electrodes (15) projecting inwardly and connected through a protective resistance (15) to a high-voltage supply (17). A rear counter-electrode (7, 26, 27) comprises an earthed conductive body (7). The displacement bodies (21, 22) accelerate the flow of powder particles. The latter come repeatedly in contact with the inner surface (11) of the powder pipe (1) and the displacement bodies (21, 22) communicating negatively charged particles (10) to them, after charge separation, whereas the positively charged particles (4) remain attached to the powder particles.

Abstract: A hand-operated electrostatic spraygun comprises a gun body, a pistol tube of insulating material, a handle, an insulation-clad high-voltage generator and a connection for paint delivery and is contructed such that the gun is particularly small, lightweight and can be effortlessly held in the hand. The gun body, preferably composed of aluminum, is an essentially cylindrical body which comprises the connection for paint delivery in the region of its forward end adjacent its forward face. The pistol tube, preferably formed of plastic, is secured to the forward face of the gun body in a manner to be secured against twisting and comprises a clover leaf-shaped cross section having two to four "leaves". The high-voltage generator is secured at the rear region of the end body to the underside thereof, whereby the cladding of the high-voltage generator is shaped as a pistol grip and forms a handle for the spraygun.

Abstract: The invention relates to a method and apparatus for electrostatic spraying of powder particles on a surface to be coated. The carrying gas powder mixture axially discharged from a nozzle is expanded by a radially discharged control air stream to thereby form the desired spray mist. The electrostatic charging of the powder is achieved by an ionized gas stream which is fed into the carrying gas powder mixture separately from the control air stream. Some of the advantages achieved by the invention are an improved spray pattern and a more uniform coating.

Abstract: A spraying gun for electrostatic spraying of coating material on an article contains a discharge electrode which is disposed entirely outside the region where the coating material flows. The coating material is accelerated through an annularly shaped and axially extending channel in which the coating material is electrically charged by friction between itself and the insulated walls that define the channel. A gas conduit extends from the discharge electrode and reaches into the annular feed channel of the coating material. Location of the gas conduit between the discharge electrode and the feed channel allows the gas flowing in the gas conduit toward the feed channel to serve the dual purposes of preventing coating material from flowing to and settling on the discharge electrode and providing an electrically conductive path through which undesired electrical charges which develop on the walls of the feed channel discharge to the discharge electrode.

Abstract: A feed channel is provided upstream of a powder-spraying discharge opening in a spray device, with a pipe having an injector which coaxially surrounds such pipe length for the coaxial introduction of accelerating gas. Downstream of the injector an elongated guide member is present in the feed channel. In this way the complete cross-sectional shape of the feed channel is progressively changed along the longitudinal axis of the feed channel to a cross-sectional shape which is annular and has a smaller cross section of flow passage. This results in a further accelerating of the stream of powder. The guide member and the region of the wall of the feed channel which surrounds the guide member at a distance therefrom consists of an insulating material on which powder particles which move past are charged electrically by friction.

Abstract: An air atomizing nozzle assembly for electrostatic spray guns. The nozzle assembly includes a fluid tip through which liquid coating material is emitted, an air cap having openings through which pressurized air passes to atomize the liquid coating material emitted from the nozzle and having a pair of opposed air horns through which pressurized air passes to shape the atomized coating material into a flat fan spray pattern, and a retaining ring for securing the air cap to the gun barrel and fluid tip. An annular diffuser is located within an internal chamber in the nozzle assembly which receives the prezzurized fan-shaping air from a passageway passing through the barrel of the gun, redirects it, and equalizes the flow of the fan-shaping air to the opposed air horns. The present invention is particularly useful in applications having low liquid coating material flow rates on the order of less than about 3 fluid ounces of material per minute.

Abstract: Disclosed is a spray gun having a gas nozzle and a fluid nozzle, each of said nozzles being in cooperative spatial relationship with the other to cause a fluid stream issuing from the fluid nozzle to be atomized and sprayed as fluid particles by gas issuing from the gas nozzle. In a preferred embodiment the fluid nozzle orifice has therein an axially disposed rod to increase surface area from which said fluid particles can be formed, said rod being electrically grounded at least during fluid issue from the nozzle. The spray gun additionally has an induction charging electrode disposed adjacent the gas and fluid nozzles, said electrode defining a charging zone wherein an electrostatic charge is imparted to atomized electrically-chargeable fluid particles.

Abstract: A high voltage charge at very low amperage is impressed on a bath of oil or other lubricant in a dielectric header through a submerged electrode. A grounded high speed moving metal strip attracts streams of the charged bath across its width through apertures or slots provided in the header. Pressurized air jets directed at these streams disperse the streams into a multitude of finer crossing streams which coat the strip completely and evenly. A recovery system for the oil or other lubricant is provided.

Abstract: An air atomizing nozzle assembly for electrostatic spray guns is disclosed. The nozzle assembly includes an air cap having a central bore which surrounds a fluid tip nozzle. The bore has a plurality of axially aligned holes evenly spaced about its circumference and intersecting the edge thereof thereby defining a plurality of uniformly dimensioned, circumferentially spaced axial gas flow passages with spaced, radially extending ribs therebetween. The ribs between the holes engage the outside diameter of the nozzle to align its center axis on the axis of the central bore. The air cap and nozzle tip thus cooperate to form a plurality of uniform gas flow passages around the nozzle thereby producing a uniform atomizing air flow pattern around the nozzle. The air cap is retained in a one-piece resilient retaining ring by snapping the air cap into position over an annular lip of the ring. The air cap and retaining ring form a seal which prevents control air from escaping to the atmosphere.