Abstract: A device for the powder coating of objects includes a main body on which an electrode arrangement designed for producing a powder cloud is arranged and on which a metering device is arranged above the electrode arrangement and is designed for the controlled discharge of an amount of a powder onto the electrode arrangement. A powder coating installation is equipped with at least one such device for powder coating.

Abstract: A system for fluid transport is provided where a quantity of fluid is held in a reservoir. A droplet generator is employed to generate droplets from the fluid, for example a nozzle-based system or a nozzleless system such as an acoustic ejection system. A generated droplet has a trajectory whereby it arrives at a target. A circuit is used to modify one or more characteristics of the generated droplet in a way which increases the likelihood that the droplet will not splash or bounce when it arrives at the target. The circuit may in different embodiments control the speed of the droplet or the Weber number of the droplet. The circuit may create an electric field in an area of space where the droplet passes. The circuit may charge the droplet by causing it to contact ions.

Abstract: A system for fluid transport is provided where a quantity of fluid is held in a reservoir. A droplet generator is employed to generate droplets from the fluid, for example a nozzle-based system or a nozzleless system such as an acoustic ejection system. A generated droplet has a trajectory whereby it arrives at a target. A circuit is used to modify one or more characteristics of the generated droplet in a way which increases the likelihood that the droplet will not splash or bounce when it arrives at the target. The circuit may in different embodiments control the speed of the droplet or the Weber number of the droplet. The circuit may create an electric field in an area of space where the droplet passes. The circuit may charge the droplet by causing it to contact ions.

Abstract: A processing apparatus includes a spin coating chamber, an ultraviolet curing chamber, a transfer module and an enclosure. The transfer module is assigned with a plurality transfer destinations, in which two of the transfer destinations are respectively located within the spin coating chamber and the ultraviolet curing chamber. The transfer module, the spin coating chamber and the ultraviolet curing chamber are enclosed by the enclosure.

Abstract: Methods are disclosed including applying a layer of binder material onto an LED structure. A luminescent solution including an optical material suspended in a solution is atomized using a flow of pressurized gas, and the atomized luminescent solution is sprayed onto the LED structure including the layer of binder material using the flow of pressurized gas.

Abstract: A plasma coating system includes at least one coating station with a first side and a second side defining a pathway with at least one bend. The coating station also includes a first plasma arc that provides a plasma jet directed towards a substrate. The first plasma arc is positioned on either the first side or the second side of the bend.

Abstract: Biocompatible coatings for implantable medical devices are disclosed. Embodiments of the invention provide methods for coating an object with a biocompatible coating wherein the device is suspended using a flowing gas during the coating process. Embodiments of the invention provide tropoelastin coatings and methods of creating tropoelastin coatings for implantable medical devices. Optionally, the biocompatible coating can be a drug eluting coating.

Abstract: Method for production of deposit or layer of nanoparticles or a layer of nanofibers from solutions or melts of polymers in electrostatic field of a high intensity, during which the produced nanoparticles or the produced nanofibers deposit on a substrate material passing through the active chamber, in which is positioned the active electrode. The electrostatic field for production, transfer and depositing of nanoparticles or production, transfer and depositing of nanofibers is induced between the active electrode and the substrate material, on which in the direction of its movement in front of and/or opposite to the active electrode there is applied an electric charge of opposite polarity than that of the active electrode, while an electric charge applied on the substrate material is being partially or totally consumed through depositing of nanoparticles or nanofibers on the moving substrate material.

Abstract: Method for treating a large number of meat products, in particular slaughtered poultry or parts thereof, in which an additive is added to the meat products. The meat products are supplied to additive-adding means using a conveyor means, the conveyor means being designed to feed the meat products sequentially in groups or separately. The additive-adding means subject each meat product or each group of meat products to an additive-adding treatment which is adapted to the corresponding meat product or to the corresponding group of meant products.

Abstract: The invention relates to a method for priming a substrate by contacting the substrate with a primer fed from a primer source and depositing the primer on the substrate. Compared to other priming methods, the claimed priming gives better results because the deposition is carried out electrostatically.

Abstract: A semiconductor light-emitting device has a semiconductor layer containing Al between a substrate and an active layer containing nitrogen, wherein Al and oxygen are removed from a growth chamber before growing said active layer and a concentration of oxygen incorporated into said active layer together with Al is set to a level such that said semiconductor light-emitting device can perform a continuous laser oscillation at room temperature.

Abstract: An applicator operable to apply an additive to a smoking article wrapping material comprises a conveyance mechanism for conveying the wrapping material along a path and an inlet to receive a gaseous flow for entraining additive, the applicator being configured such that in use, additive entrained in the gaseous flow is caused to be diverted towards the wrapping material.

Abstract: An electrostatic coating method in which a coating material cartridge is used. When a coating material feeding path (68, 88) is cleaned by a liquid fed from a coating material feeding unit (20), the liquid is fed from the coating material feeding unit to a storage part (13) and stored. The liquid in the storage part is then fed to a fluid chamber (83) inside a coating material cartridge (19) via a fluid circuit (10A). The liquid in the fluid chamber pushes out the electrically conductive coating material inside a coating material chamber (84) via a free piston (82), and the electrically conductive coating material is fed to a coating gun (14).

Abstract: A semiconductor light-emitting device has a semiconductor layer containing Al between a substrate and an active layer containing nitrogen, wherein Al and oxygen are removed from a growth chamber before growing said active layer and a concentration of oxygen incorporated into said active layer together with Al is set to a level such that said semiconductor light-emitting device can perform a continuous laser oscillation at room temperature.

Abstract: A liquid droplet ejection apparatus has a droplet ejecting portion and an energy beam radiating portion. The liquid droplet ejecting portion ejects droplets containing pattern forming material onto an ejection target surface. The energy beam radiating portion radiates an energy beam onto a boundary between the droplets that have been received by the ejection target surface at different timings so as to move boundary areas of the droplets. Accordingly, using the liquid droplet ejection apparatus, a pattern having an accurately defined shape can be formed.

Abstract: An SOD system (100A) comprises a process block (8) for performing a prescribed processing so as to form an insulating film on a wafer W, a carrier block (7) for transferring the wafer W from the outside into the process block (8), a sub-transfer mechanism (12) for transferring the substrate W between the process block (8) and the carrier block (7), and a main transfer mechanism (15). A process tower (T1) prepared by stacking one upon the other a plurality of process units for performing a series of processing for forming an insulating film on the wafer W is arranged detachable from the process block (8).

Abstract: A stent mandrel fixture for supporting a stent during the electrostatic application of a coating substance is provided.

Abstract: A method and apparatus are presented for electrostatic deposition of dry powder to a tablet, capsule, or a specific area of any of a wide range of pharmaceutical substrates. The apparatus includes: a magnetic brush having a rotatable multi-pole magnetic core and a stationary outer shell; a developer supply for supplying a magnetic developer powder, consisting of a magnetic carrier particles and pharmaceutical dry powder particles, to the magnetic brush; a print head on the outer shell; a tablet or other pharmaceutical substrate arranged in spaced relation to the print head to define a pharmaceutical powder transfer region through which the substrate can be moved.

Abstract: A powdery layer is formed on a first side of a web (W) which serves as a substrate by applying electrically charged particles on the web while a rotating grounding electrode is located at a second side of the web.

Abstract: The invention provides apparatus for electrostatically coating a pharmaceutical tablet core with powdered coating material. The apparatus comprises a first rotary drum (12) on which a core is held in electrical isolation from its surroundings but at a potential differecne to earth by an electrode which contacts the core. The core is carried past a coating station B at which particles of powder having an opposite potential difference to earth are held in a tray (18). The surface of the drum is held at the same potential difference to earth as the powder particles. The powder is attracted to the core, and not to the drum, coating the exposed surface of the core. The drum carries the coated core past a fusing station C at which a heater fuses the powder to form a continuous film coating. The core is then turned and transferred onto a second drum (12?) where the other surface is coated in the same way.

Abstract: A device for moistening a material web moved in the transport direction, is preferably used for re-moistening a paper or textile web dried after printing by means of spray device for spraying a water fog onto the material web under the influence of an electrostatic field produced by a device for electrostatic charging. The device includes a reversing roller provided in the transport direction upstream of the spray device for deflecting the material web. The reversing roller has associated with it a device designed as a corona-charging electrode for electrostatic charging and the spray device has two water spray heads located on both sides of the material web.

Abstract: An apparatus for applying powder to at least an interior surface of a hollow object includes a powder discharge device adapted to receive powder and discharge the powder through an outlet. An object holder is configured to hold the object such that the outlet is positioned within the hollow object adjacent the interior surface. A rotating mechanism is configured to engage and rotate the hollow object such that the powder discharged from the outlet coats the interior surface as the interior surface rotates past the outlet. The powder discharge device may be a powder fluidizing bed unit including a chamber with a powder discharge opening in the form of an elongate slot.

Abstract: A painting apparatus includes a conveyor having incrementally spaced attachment structures configured to secure objects thereon for painting and being movable to move the attachment structures between consecutive incremental positions in a downstream direction. The distance between consecutive incremental positions is generally equal to an incremental spacing between consecutive attachment structures. A washing station is disposed beneath the conveyor and is operable to clean objects disposed therein. A painting station downstream of the washing station includes a paint reservoir disposed beneath the conveyor and which contains a volume of paint. The reservoir can be raised to dispose the object within the volume of paint and lowered to thereby allow the object to be conveyed downstream from the painting incremental position. A heating station downstream of the paint reservoir applies heat to objects in a heating incremental position.

Abstract: An apparatus for and method of coating the outer surface of a non-rotating pipe with a fluid including a fluid reservoir for containing fluid to be discharged onto the surface of a pipe, and a pipe receiving chamber extending through and separate from the fluid reservoir. The apparatus further includes a fluid application assembly having a plurality of fluid intake openings positioned in the fluid reservoir for the intake of fluid therefrom. The fluid intake openings are rotatable in a circular pattern within the reservoir about a path extending through the chamber. The assembly has a plurality of fluid discharge outlets in fluid communication with the fluid intake openings and directed towards the path. The fluid discharge outlets are rotatable in unison with the fluid intake openings about the path, whereby fluid entering the fluid intake openings from the reservoir is discharged through the fluid discharge outlets to coat the outer surface of a pipe being conveyed along the path.

Abstract: An electrostatic powder coating apparatus including a housing with an interior coating area for receiving a workpiece. The interior coating area includes a vortex inducing surface and a pressurized air input device directs air against the surface to form a swirling pattern of air around the workpiece. A powder introducer directs charged powder into the swirling pattern of air and the powder is then electrostatically attracted to the workpiece. The powder introducer may be a powder fluidizing bed disposed in the housing or other suppliers, such as electrostatic powder spray guns. In alternative embodiments, vortex generators in the form of tubular structures connected proximate the housing inlet and outlet have tangential ports for introducing positive pressure air or inducing vacuum in the tubular structures.

Abstract: The invention relates to a method and device for improving the coating surface of a coating mass deposited on or applied to a paper web (8, 23) by a film press. An anionic aqueous coating mass or an anionic paper web are provided with an opposite electric charge by an electric charger, whereby the applied coating is attracted to the oppositely charged paper (8, 23) in a nip exit area of the film press. The electric charger is, for example, a corona generator (13, 17) or a direct current voltage source (9) that is connected to the paper (8, 23) and coating slip by electrodes (5, 5a, 7, 7a).

Abstract: A coating method and apparatus are taught for coating a liquid composition onto a surface of a moving web. A coating hopper for delivering the liquid composition to the surface of the moving web is provided with a rotatable backing roller. The moving web is wrapped around a portion of the rotatable backing roller with the rotatable backing roller supporting the moving web through a dynamic wetting line. The rotatable backing roller includes a plurality of circumferential grooves therein at a groove pitch of at least two per millimeter. An electrostatic field generated across the gap between the moving web and the liquid composition immediately prior to the dynamic wetting line. The method and apparatus permit either coating at a higher speed or higher viscosity than may be achieved in the prior art, or greatly reduced groove line nonuniformity at a given coating speed and viscosity.

Abstract: In equipment for powder-coating, workpieces such as escalator steps are subjected to a current treatment in an anodizing unit. A conveying means advancing carriers for the workpieces is lowered over a tank so that the workpieces in transit are immersed in and continue transit within a bath and after a specific dwell time are lifted back out of the bath at the end of the tank. Arranged in the tank region is a current feed, such as a bus bar, which extends parallel to the travel path of the conveying means. Each carrier is provided with a current take-off which connects the carrier with the current feed. The current connection is produced on lowering the carrier into the bath and interrupted on raising the carrier from the bath.

Abstract: An electrostatic powder coating system that comprises a booth, the lower part of which is designed in the shape of a V, and a collecting channel (13), connected to a suction device (2) underneath, the booth having two ends, each of which has a pass-through opening for the workpieces. The collecting channel (13) is covered by floor plates (17), which can be walked upon or swung up into a vertical position, and which are provided with exhaust slots (18, 19, 20) extending in the longitudinal and transverse directions, it being advantageous for the total area of the slots be a function of the discharge of exhaust air and the velocity of the exhaust air.

Abstract: A treatment method for the internal surface of a moulded polyethylene plastics material container such as a drum, comprising the steps of: introducing an ionisable gas, such as argon, into the container; generating a plasma of the introduced gas by applying electric field of sufficient strength to the container and introduced gas, so as to cause an interaction with the internal surface of the container; coating the internal surface of the container with a curable epoxy-based first polymeric composition; and then curing the polymeric composition to form a coating on the internal surfaces of the container. A second coating, preferably with electrical conductive properties, may be applied and cured over the first coating. Conductive properties may provided by including conductive particles such as antimony doped tin dioxide, graphite or metal powders, in the second composition.

Abstract: Plant for powder coating the surfaces of objects with polymeric powder having a melting and softening temperature below 100° C. The polymeric powder includes a polymer curable under the influence of electromagnetic radiation. Objects to be coated are prepared to retain powder charged with static electricity. The objects are then sprayed with powder charged with static electricity and thereafter heated to a surface temperature of about 100° C. thereby melting the powder retained on the surface by exposure to infrared radiation and heated air. The objects are radiated by electromagnetic radiation for curing of the powder over the surface of the objects.

Abstract: An apparatus for the coating of flat-form substrates, especially of printed circuit boards, solder masks and the like, wherein there is arranged between two coating stations a turning station for the printed circuit boards, which are conveyed on a transporter pathway through the coating stations and the turning station, wherein in the turning station (4) there are provided in the same plane as the incoming transporter pathway (2) receiving elements (5) located, spaced apart, opposite one another, which enter into engagement with the edge of a printed circuit board (11) or a holding element attached to the printed circuit board, it being possible to pivot those receiving elements (5) through 180.degree. so that, when the printed circuit board is discharged, they again lie in the plane of the onwards-leading transporter pathway (2').

Abstract: A chemically washed workpiece is heated and degreased by a heating and degreasing section in a process for delivering the workpiece in a base which is then cooled down in a cooling section. The workpiece is then delivered onto the base by a lift-up unit and is coated by the adhesion of the powder coat and the curing operation during the passage of pipes of an electrostic coater, a curing section and the like. Furthermore, the workpiece is again delivered into the base by a lift-down unit and discharged after being cooled down during the passage of pipes of the cooling section i.e., the units of each step being arranged separately into a lower mechanism group and an upper mechanism group, and the cooling section also serving to cool the workpiece after the heating, degreasing and curing. Accordingly, the overall length of the apparatus is shortened.

Abstract: A device for applying powder to sheets passing sequentially through a printing press in a conveying direction along a conveyor route, the sheets being combinable into a sheet pile in a manner that one respective side of upper and rear sides of a respectively following sheet is situated opposite the other respective side of the upper and rear sides of a respectively preceding sheet, includes a device for generating a powder-bearing gas curtain associated with the conveyor route and formed of a carrier gas conveying powder particles, and for applying the powder of said gas curtain to the rear side of the respective sheets prior to the combination of the sheets into the sheet pile.

Abstract: A composite manufacturing system moves a multi-fiber tow through a processing space. A resin particle source provides particles to the space. This source may include an airstream entrained with particles which is discharged into the space through an orifice; the airstream diverging as it enters the space. An electrode is disposed in the space to electrostatically charge the particles and facilitate deposition of the charged particles on the tow. In one embodiment, the electrode includes a corona wire disposed proximate to the tow to provide a generally cylindrical charging region. An electric field useful to direct deposition of the particles may be generated by appropriately shaping a wire electrode and orienting it in a predetermined manner relative to the tow. After the particles are deposited, a fixation unit may be used to at least partially melt the deposited particles. A processing stage may be included which has a pair of surfaces configured to heat and compress the tow therebetween.

Abstract: An apparatus 100 is provided with: a supply section 1 for supplying a paper base material P; a storage section 21 for storing a white fine particles coating; a development section 2 having a sleeve 22 for holding the white fine particles coating from the storage section 21, a blade 23 for controlling a thickness of the white fine particles coating held by the sleeve 22, and a charge drum 24 for absorbing the white fine particles coating from the sleeve 22; a transfer section 3 for electrostatically transferring the white fine particles coating absorbed by the charge drum 24 onto the paper base material P; a fixing section 4 having a heat roller 41 and a press roller 42, and for fixing the white fine particles coating on the paper base material P; and a ejection section 5 for ejecting the paper base material P fixed the white fine particles coating by the fixing section 4. By using the apparatus 100, the thermal transfer image receiving sheet S on which a high quality image can be formed, is produced easily.

Abstract: The present invention provides an apparatus for controlling the spray of positively-charged coating particles towards a grounded or negatively-charged dielectric material having a dielectric constant less than 4.0 and in the form of a hollow container.

Abstract: The electrostatic fluidized bed coating apparatus and system employ a vertically extending gaseous vortex of charged particles. Effects of variations in particle distribution, size, and electrostatic charge strength are minimized by the vertical orientation, enabling the production of coatings of exceptional uniformity. The apparatus is especially suited for construction to simultaneously coat a number of strands of wire or the like.

Abstract: Apparatus for electrostatically applying a coating to articles in a chamber includes nozzles for discharging a fluid stream of coating composition, usually a dry powder, into the chamber. An electrical charge is applied to the individual particles of the coating composition. An endless conveyor supports suspended racks on which the articles to be coated are supported. Electrically grounded conductive strips having a projecting edges electrically ground each of the racks they move through the chamber. The strips have a thin flat profile with a laterally projecting edge to frictionally engage the racks moving through the chamber. Preferably the edge is vertically inclined so that the point on the racks contacted by the edge continually varies as the racks are conveyed, thus insuring a scraping action and good electrical contact between the grounding strip and the rack.

Abstract: A support for parts being electrostatically coated or painted as mounted upon an electrically charged rack wherein the support is formed of a flexible material and includes a flexible electrical conductive portion engaging the rack and part permitting the part to be charged, and a flexible non-conductive portion frictionally engaging the part. The support may include a masking cover defined on either of the portions engaging and protecting the part from painting. The support may be formed of thermoset rubber material, thermoplastics, polyvinylchloride material, or the like.

Abstract: This method and apparatus provide for uniformly coating a hot elongate member with a powder coating. The elongate member and power carry an electrostatic charge which aids in providing the uniform powder coating. This method and apparatus electrostatically charge and heat the elongated member prior to entering a powder coating booth. In the booth, we sequentially discharge the powder coating, electrostatically charge the powder coating and then coat the elongated member with the charged powder coating. In one development, this method and apparatus uniformly powder coats window lineals directly on a pultrusion line.

Abstract: A conveyor device for applying a high voltage to a work transported in a coating booth includes a conveyor device main body having a running base running in the coating booth and an electrode attachment attached to the running base being insulated therefrom for carrying the work and applying a high voltage to the work, an electromagnetic wave transmitter disposed in the coating booth for transmitting electromagnetic waves to the running base during running in a high voltage application zone and a low voltage generator means for receiving electromagnetic waves from the electromagnetic transmitter means and a high voltage generator for stepping-up a low voltage outputted from the low voltage generator and supplying a high voltage to the electrode attachment, mounted on the running base.

Abstract: Apparatus for applying powdered coating to a workpiece--particularly to electric motor armatures and stators--including features relating to handling and masking of workpieces before, during and after coating, is provided. A first feature of the invention is the inclusion of all coating steps--e.g., coating, cleaning and precuring--as modules in a single treatment station on the production line. The treatment station can also be enclosed in a single housing to contain excess powder from both the coating and cleaning processes, so that a single powder recovery system can be used to recover the excess powder from both processes. The invention also includes a handling system for removing the workpiece from the production line, inserting it into the treatment station and moving it past the various modules in the treatment station, withdrawing it from the treatment station, and returning it to the armature production line.

Abstract: Non-magnetic and non-conductive powdered toner is applied to a rotating image cylinder having an electrostatic pattern. A container having a closed bottom and sides and open top contains the powdered toner. The powder is fluidized by introducing air through a pervious closed bottom of the container, and by vibrating the container. The toner is simultaneously stirred and electrically charged to a potential of greater than about 7 kv (plus or minus polarity) by rotating elements with radial pointed appendages in the container. Toner is transferred from the container to an image cylinder at an exposed nine o'clock position of the image cylinder by a plurality of transfer cylinders. A first transfer cylinder is mounted so that its periphery is just above the open top of the container and an applicator cylinder has its axis below the axis of the first cylinder, and its periphery adjacent both the first cylinder and the image cylinder.

Abstract: A method of electrostatically painting and an apparatus for producing an electric field within a booth includes a paint spray gun charged to a first potential and a target to be painted to a second potential with one of the panels in the booth charged to a third potential intermediate the first potential and the second potential to repel paint particles away from the panel. The paint particles and the panels are charged to the same polarity and the target is of the opposite polarity. The panel is usually a wall, a ceiling and/or a conveyor protection housing within the paint spray booth. The preferred panel comprises an outer insulating layer of plastic, glass or porcelain that is easily wiped of paint and an interior, electrically-conducting layer such as a thin sheet of aluminum. Variations of the panel include a version which is completely enclosed in plastic and a version which is bonded to plastic.

Abstract: A conveyer for transporting a part to be painted through a paint booth and drying and curing apparatus. The conveyer includes a transporter having an upwardly extending post, a tubular lifter disposed on the post and having a contoured lower surface which engages a pin on the post for supporting the lifter at a first elevation on the post when the lifter is in a first angular position and at a second lower elevation when the lifter is at a second higher elevation on the post. A fixture includes a pipe telescopically received on the post and having a lower end rotatably supported on the lifter when the lifter is in its first angular position and being lowered into engagement with a stop pin on the post when the lifter is in its second angular position. The fixture includes a support at the upper end of the pipe for supporting the part to be painted.

Abstract: A full automatic coating system includes an endless metal tape driven to run in one direction along an endless traveling path, a product supplying station for automatically selecting products of a desired type and supplying them to the endless metal tape according to a production control procedure stored in a control unit, a coating station disposed in the traveling path downstream of the product supplying station and including a spray gun for selectively spraying one of coatings of different colors according to instructions received from the control unit, a drying and baking station and a coating removing station disposed in the traveling path downstream of the coating portion in the order named. All the components are linked to operate in timed relation to one another according to the instructions received from the control unit.

Abstract: In a system and method for forming a metal oxide coating on glassware, heated glassware is provided in a coating zone, preferably by a grounded conveyor. An electrostatic charging and depositing field is established to a surface of the glassware in the coating zone, and a flow of metallic vapor is generated and introduced into the electrostatic charging and depositing field. The metallic vapor is electrostatically deposited on the surface of the heated glassware, and reacts with oxygen at the surface of the heated glassware to form a metal oxide coating on the surface of the glassware. The system and method can be used in either cold end coating or hot end coating, and can provide a dual cold end coating with an initial metal oxide cold end coating and a subsequent conventional cold end coating, providing improved surface lubricity at reduced costs.

Abstract: An apparatus for and method of coating an article by the use of electro-static attraction of ionized particles which are subsequently cured. The apparatus includes a first foraminous conveyor for carrying the article through a powder coating zone and a second conveyor for carrying the article through a curing zone. The surface of the article which rests on the foraminous conveyor is cleaned of particles as the article is transferred from the first foraminous conveyor to the second conveyor. The first foraminous conveyor is also cleaned of particles after the article has been transferred. After the articles have been cured to form a coating on the article, the article is put through the coating system again except that the article is supported on the conveyor so that the surface which was not coated in the first pass through the system is out of contact with the conveyor.

Abstract: An electrostatic spray apparatus, including a spray hood having an electrode. The hood defines a top region with a depending skirt and comprises first and second hood elements, either or both of which may comprise molded shells, with an electrode sandwiched therebetween. The electrode extends over the top region and down the skirt and terminates short of the lower regions of the skirt. The hood is constructed such that, other than at the lowermost regions of the skirt, the hood does not have any junction of its planar surfaces having a radius less than one hundred and fifty millimeters. The hood has an opening in its top region, through which an electrostatic spray head is placed into the hood. The electrode presents a connection for an electrical supply, and the potential applied to the spray head is substantially the same as that applied to the electrode.