Abstract: A electrohydrodynamic aerosol sprayer wherein a gas flow deflector is used for creating a gas flow past the spray nozzle to stabilize the Taylor cone and to transport at least a portion of the aerosol away from the region downstream of the spray nozzle. This stabilization of the cone and transport of aerosol improves the droplet size and distribution and may also reduce the deposit of droplets on the internal components of the device.

Abstract: A device and method for atomizing a liquid medium, including an electrically conductive nozzle body with an internal volume for holding the liquid medium, at least one nozzle opening as well as a high-voltage electrode arranged inside the internal volume coaxially to a longitudinal axis of the nozzle body. The high-voltage electrode is provided in the area of its greatest lateral expansion with a circumferential, sharp edge that extends at a small distance to the nozzle body in order to be able to bring about the electrostatic charging of the passing liquid medium. This construction enables the electrostatic atomization in a simple manner even for multi-hole nozzles, so that the electrostatic atomization also can be used in the field of gas turbine technology for improving the injection in the start-up and partial load range.

Abstract: In accordance with the present invention there is provided an apparatus for electrostatically dispensing small volumes of biological or chemical material from a dispensing tip or array of dispensing tips. The apparatus includes a voltage generator, a dispensing head containing the liquid to be dispensed, and an electrode that is in electrical communication with the liquid such that when a voltage pulse is applied to the electrode, the liquid is dispensed from the dispensing head onto a receptacle. The apparatus also can include an electrostatically charged counterplane and can include a guard shield. The invention also provides for means for movement of the dispensing apparatus and the receptacle relative to each other. The invention also provides methods for dispensing fluids onto a receptacle surface, including 96-, 384- and 1536-well plates.

Abstract: A comminuting liquid device, a medicament delivery device, an inhaler, a method of providing droplets for delivery to the respiratory tract, a pocket-sized dispenser, and a method of mixing liquids by droplet coalescence. Liquids are subjected to electrical potentials to produce electrically charged droplets for delivery to the upper respiratory tract.

Abstract: The slurry distributor comprises two or more square pipe sections in end-to-end relation having an inlet at one end for connection to a slurry supply and provided with discharge openings equally spaced longitudinally thereof; on each side of the square pipe for discharge of the slurry, the openings being successively obstructed manually or by deposited solids from the slurry itself piling up on the original ground level. The distributor is used to control the slurry composition for dyke building and general tailings disposal consisting of mine tailings.

Abstract: A device for comminuting liquid has a liquid supply with first and second outlets, a first electrohydrodynamic comminuter for subjecting liquid issuing from the first outlet to an electrical potential to cause the liquid to be commrinuted to form a comminution of one polarity and a second electrohydrodynamic comminuter for subjecting liquid issuing from the second outlet to an electrical potential to cause liquid to be commninuted to form a comminution of the opposite polarity. The first and second electrohydrodynamic comminuters are arranged so as to cause substantial admixing of two opposite polarity comminutions.

Abstract: A powder spray gun, and method for using same, is disclosed. The powder gun includes a corona discharge tip and mesh screen within the passage for powder flow. A potential is applied to the corona discharge tip, resulting in an electric field between the corona discharge tip and mesh screen. This electric field efficiently charges powder particles passing through the spray gun, but the mesh screen blocks most of the free ions that are generated by the corona discharge tip. Any free ions that pass through the mesh screen are captured by a conductive end piece on the spray gun. A potential difference is applied between the end of the spray gun and the workpiece to guide the charged powder particles to the workpiece.

Abstract: A device for dispensing a comminuted liquid to the upper respiratory tract, which comprises an electrohydrodynamic comminution device and a supplier of a liquid to the comminution device. And a device for comminuting a liquid, the comminution site of which is provided by fibers projecting from an end surface or edge, the edge or surface being composed substantially of fibers.

Abstract: Apparatus for powder spray coating comprises means for electrostatically-charging powder entrained in air, a conduit for transporting the electrostatically charged powder from the charging means to a spray head adapted to discharge the powder in a hollow conical spray pattern, wherein the spray head comprises means for diverting at least a portion of the flow of charged powder towards a spray device mounted to the spray head and adapted to discharge powder in a substantially uniform conical spray pattern, the spray head, spray device and the hollow conical and conical spray patterns being substantially symmetrical about a common longitudinal axis. The apparatus is particularly suitable for coating a large surface area. Preferably multiple tribo-electric charging means are used and a pump is used to supply powder to the multiple charging means through a common distributor. After passing through the multiple charging means the powder flows are then recombined and sprayed through a common spray apparatus.

Abstract: An improved apparatus for applying coating material includes a spray head having a housing which encloses a deflector. The deflector and housing cooperate to form a plurality of coating material flow channels which diverge in a direction of flow of coating material through the spray head. The deflector and housing cooperate to define a long thin outlet with relatively wide channel outlet sections at opposite ends of the outlet. An electrode assembly includes an electrode element having a long thin surface area which extends between opposite end portions of the long thin outlet and is exposed to the flow of coating material through the outlet. A wear tube encloses a portion of the electrode assembly and connects the deflector with the housing. The electrode element may be a plate which is molded into the deflector with a minor edge portion of the plate exposed to the flow of coating material.

Abstract: A durable electrospray needle uses a capillary having a substantially large outside diameter. Provision of a porous bead at the spray tip advantageously allows a fine electrospray to be formed without the need for finely machining a needle tip and orifice, which allows for economical construction. Further, because the bead itself may serve as the anode in an electrospray field circuit, costs associated with electrode placement are eliminated.

Abstract: An electrospray adapted fuel injection valve includes an anode and cathode to inject monopolar electric charge into electrically insulating fuel. On exiting the injector, the charge containing fuel atomizes and disperses to reduce electrostatic energy. Additional electrodes with an appropriate method of biasing extend the range of applicability of the process by adjusting space charge distribution within the injector to compensate for variability in component manufacture and variability in the electrical conductivity of the fuel.

Abstract: Electrostatic spray appliance for coating material for the spray-coating of articles comprisesa single carrier (4) which carries a plurality of gun barrels (6, 8), so that the carrier (4), together with the gun barrels, forms spray guns. The gun barrels (6, 8) are releasably fastened to the carrier (4). The supply lines (54, 56, 58, 60, 62, 64, 78) are combined to form a line bundle and are led through a movable robot arm (68) in the longitudinal direction of the arm on the side of the carrier (4) facing away from the gun barrels (6, 8). The spray nozzles (12) are preferably slit nozzles having slits arranged obliquely relative to their theoretical connecting line.

Abstract: Relatively low resistivity liquids are formed into sprays under the influence of an applied electric field acting between a nozzle and the nozzle surroundings which may be at earth potential. The liquid issues from the nozzle as a ligament which undergoes necking to a diameter smaller than that of the nozzle orifice, thereby producing droplets with a volume median diameter less than the orifice diameter.

Abstract: An electrostatic spray nozzle that is positioned at an angle above horizontal and less than vertical having a body with an upper fluid emitting end and a lower bottom end. The body having an interior cavity therein. Within the cavity is a shim capable of conducting electricity that defines an opening at the fluid emitting end and a channel that joins the fluid emitting end opening to a supply of flowable material. The body has an enclosed electrode external adjacent to and below the emitting end. Both the shim and the electrode are electrically connected to a voltage source. The nozzle, in operation, bends the field adjacent the emitting end upwardly in accordance with the method of the invention.

Abstract: A nozzle assembly for electrostatically dispensing a flowable material at a controllable rate and in a reliable and uniform manner includes a housing with a dispensing edge and front and rear members joined together to provide a continuous dispensing slot along the dispensing edge. The nozzle is a unitary device having a plurality of substantially hydraulically independent chambers therewithin in fluid communication with the substantially continuous and uninterrupted dispensing slot, whereby flowable material can be selectively supplied to the individual chambers to control the width of material application without structurally modifying the nozzle itself. Field gates are provided at each end of the nozzle to further control the deposition of the charged material, and the nozzles can be oriented to dispense flowable material in substantially any orientation, including vertically upwardly.

Abstract: An electrostatic spraying apparatus is in the form of a device suitable for hand held use. The device uses a high voltage generator of the rectified pulsed type and includes an earth return path which is completed via the operator through a contact (38) associated with the hand grip (4) of the device. Resistance (36), typically of the order of 50 megohm, suppresses pulsed electrical sensations that may be experienced by the operator in the event that the nozzle (12) is contacted with an earthed object, and the nozzle (12) is designed so that the liquid therein presents, by virtue of the length and cross-sectional area of a liquid conducting passage(s) in the nozzle, a high resistance between the voltage generator (26) and the nozzle thereby reducing the energy that can be drawn to earth by electrical discharge.

Abstract: An electrostatic spraying device is designed in such a way that potential surface leakage paths (FIG. 1b) along which current may leak from the HT generator (2b) are sufficiently long to allow the use of a generator having a smaller than conventional maximum current output.

Abstract: Imaging apparatus including an electrostatic imaging surface, latent image forming apparatus for forming an electrostatic latent image on said electrostatic imaging surface and development apparatus for developing said electrostatic latent image which includes supply apparatus for supplying a liquid toner to the image forming surface, the supply apparatus including a multiplicity of independently controllable outlets, preferably spray outlets, and a development surface for developing the electrostatic latent image using the liquid toner. The supply apparatus is preferably a multi-color supply apparatus and the multiplicity of outlets includes a plurality of individually controllable outlets, for supplying liquid toner of each of a plurality of colors.

Abstract: An improved nozzle modulator, an improved nozzle modulator assembly, and an improved coating method comprises a nozzle having a housing. A fluid reservoir communicates with the housing. The nozzle has a nozzle outlet about which a meniscus is formed. A high voltage source is connected to the nozzle. The fluid is dispensed as one or more charged fluid paths from the nozzle upon the actuation of the high voltage source. A plurality of repulsive and attractive electric fields are positioned to surround the fluid path. An electrical biasing means is connected to the electrical fields for biasing the fields and modulating the fluid path to form a homogeneous fog comprising uniformly disbursed droplets moving in a wide variety of directions.

Abstract: In electrostatic atomization of liquids wherein a stream of electrically charged liquid is atomized under the influence of the electrical charge, the stream is surrounded by a mist to increase the dielectric breakdown strength of the surrounding atmosphere. This permits use of higher charge levels and hence more efficient atomization. The mist may incorporate minute droplets of the liquid to be atomized. An insulating vapor may be formed from the liquid by heating a portion of the liquid and employed in place of or in addition to the mist.

Abstract: Improved apparatus for indirectly charging atomized electrically conductive fluids discharged from a spray gun. One or more high voltage electrodes are located outside of the atomized fluid envelope for imparting a charge to the fluid droplets. Air curtains are established to surround insulated electrode holders for preventing a buildup of electrically conductive deposits on the holders. The air curtain is strongest at the end of the holder closest to the atomized paint envelope. The electrodes may be supported from an adapter which permits retrofitting on existing direct charge electrostatic spray guns.

Abstract: Pesticide spraying apparatus for spraying crops in the field, grapes, and seedling trees. The spraying apparatus includes a wheeled arcuate canopy open at the bottom providing a rounded arcuate interior wall and a spacing at the open bottom related to the width of one or more conventional rows of crops of the like. The canopy has an arcuate peripheral flange at each end and a downwardly extending skirt or air curtain along the bottom of each side of the canopy to confine the pesticides to the open bottom area of the spraying apparatus. One or more blowers and pesticide assembly is provided for blowing droplets along the interior inner wall of the canopy at spaced locations. An air door or curtain is also created at each open end of the canopy and droplets of pesticide are thus blown into contact with the plants to treat the same under the canopy.

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: A flat spray nozzle for a powder spray gun comprises a nozzle body formed with an axial powder flow passageway, a pair of spaced powder discharge slots intersecting the powder flow passageway and a bore located between the powder discharge slots. The bore in the nozzle body receives an electrode which extends forwardly of the spray nozzle, between the powder discharge slots for electrostatically charging particulate powder material emitted from the powder discharge slots without disrupting the spray pattern of particulate powder material.

Abstract: An apparatus and process for the electrostatic spraying of a mixture of a plurality of liquids, suitably liquids which react together rapidly to form a solid, liquids which are physically imcompatible, or liquids, such as paints, to provide novel optical effects. The apparatus includes a sprayhead formed with a plurality of channels which communicate with a common outlet means. The liquids are supplied to respective channels and meet at the outlet means. There they are subjected to an electrical field which causes a mixture of the liquids to be drawn from the sprayhead in the form of one or more filaments, the or each filament constaining a mixture of liquids in the proportions equal or substantially equal to the proportions in which the liquids were supplied to the sprayhead.

Abstract: A nozzle apparatus and method for electrically charging and dispensing fluids and other flowable materials, comprising a fluid reservoir and a housing. The housing includes walls which define a chamber having an elongated slot at the tip thereof. The slot is resiliently compressible. The reservoir communicates with the chamber such that the fluid is introduced into the chamber at a controlled rate and a low hydrostatic pressure. A shim is placed within the chamber slot partially occluding fluid flow through the slot. The shim and the amount of compression of the slot defines with precision the size and shape of the slot. The shim and fluid are electrically connected to a high voltage source through the housing. The fluid forms a meniscus about the housing slot whereby upon actuation of the high voltage source, the fluid is dispensed as one or more charged fluid paths or a plurality of charged droplets.

Abstract: An electrostatic coating system for applying very thin coating to a substrate in air at atmospheric pressure comprises a plurality of spaced capillary needles positioned in at least two rows and fed with coating liquid via a manifold. The needles are disposed concentric within holes in an extractor plate, a potential is developed between the capillary needles and the extractor plate affording a reduction of the liquid to a mist of highly charged droplets drawn to the substrate by a second electrical field. Insulative layers on the extractor plate provide increased droplet control.

Abstract: A spray gun for applying a film to a workpiece has a spray head provided with an annular nozzle designed to discharge material which is to undergo pneumatic atomization. A second annular nozzle surrounds the pneumatic material discharge nozzle and is designed to discharge atomizing air for pneumatic atomization of the material issuing from the pneumatic material discharge nozzle. The spray head is further provided with an additional material discharge nozzle designed to discharge material which is to undergo hydrostatic atomization. The hydrostatic material discharge nozzle is disposed centrally of, and is surrounded by, the pneumatic material discharge nozzle. The hydrostatic material discharge nozzle forms a first spray of hydrostatically atomized material while the annular nozzles form a hollow conical second spray which surrounds the first spray when both sprays are on simultaneously.

Abstract: A multinozzle electrostatic spraying apparatus wherein flow restrictors are provided in the liquid supply paths to the nozzles to render the liquid flow rates through the nozzles more uniform irrespective of the spatial orientation of the apparatus.

Abstract: The invention relates to a device for the powder-dusting of moving objects, particularly flat substrates in the form of webs and sheets of paper, plastic or textile with a nozzle housing made of electrically insulating material, with at least one nozzle provided on the housing for releasing a powder air stream laden with dusting powder and with metallic electrodes and counter-electrodes disposed on the housing for producing an electrical high-voltage field. To obtain a powder air stream with powder particles as neutral as possible, it is envisaged that at least one electrode and a counter-electrode cooperating with the latter are disposed on the outside of the housing in the vicinity of the nozzle whereby an electrical high AC voltage is applied to the electrode and counter-electrode, whereby, after being released from the nozzle, the powder air stream penetrates the thus produced high AC voltage field on the outside of the housing.

Abstract: Spray combination of two liquids is advantageously accomplished by applying a high potential of one polarity to a first liquid thereby converting the first liquid into finely divided ionized particles, spraying a second liquid through a porous member and applying thereto a high potential of the other polarity thereby converting the second liquid into finely divided ionized particles, and combining the two masses of finely divided particles of the two liquids electrostatically with each other.

Abstract: Oil is delivered by a single pumping means to an application header which extends across the path of movement of an electrically grounded metal strip requiring oiling. A perforated plate within the header divides it into two chambers and forms a diffuser between the two chambers to assure an even distribution of oil in the chamber which receives its oil by passage through the diffuser. The perforated plate also forms a charging electrode for oil filling the header and serves a third purpose in that it is a final filter for the oil passing through the header. The header has oil delivery orifices or a continuous delivery slot leading from the chamber of the header which faces the metal strip. Oil is attracted in small discrete streams onto the surface of the grounded strip traveling in near proximity to the header and the strip is uniformly coated with oil across its full width. Excess oil is recovered and returned to the pumping means for recycling in the system.

Abstract: A method and apparatus are disclosed for the spraycoating of the interior of a hollow body, one region of which, e.g. a seam, must receive a heavier coating than the remainder of the surface to be sprayed. A single spray coating operation is performed, in which a relatively heavy spray jet is concentrated on the seam and a relatively thin cloud of coating material is used to coat the entire interior surface of the body. Preferably, a cloud of electrostatically charged coating material is formed by an atomizer fed by a feed conduit from which a certain amount of coating material is diverted to be formed into the relatively highly concentrated spray jet directed at the seam. The relatively high-velocity particles of material of the spray jet which is concentrated onto the seam and the relatively low-velocity particles of material of the coating cloud together produce on the seam a thinner layer of material than would normally suffice and which, nonetheless, adheres well.

Abstract: A jet device for depositing fluid drops upon a moving fluid receiving medium, such as a fabric web, includes a coating head defining a fluid receiving reservoir and including an orifice plate defining a row of orifices which communicate with the fluid receiving reservoir. Fluid is supplied to the reservoir under pressure such that the fluid flows through each of the orifices and emerges therefrom as a fluid filament. The fluid filaments are stimulated to break up into jet drop streams. A charging plate of electrically conductive material defining a charging slot for charging drops formed from the fluid filaments is mounted adjacent and aligned with the coating head means such that the fluid filaments extend into the charging slot of the charging plate and break up of each of the filaments occurs within the slot.

Abstract: This invention is in an improvement in electrostatic spraying apparatus for coating objects with electrostatic powder, or dust. The apparatus includes a housing or body member having a discharge nozzle at one end and internal flow passages for conducting compressed gas supplied from an external source to the discharge nozzle and a deflector element coaxially disposed adjacent the discharge end of the nozzle. A source of powder or dust is provided and is mixed with the compressed gas to produce a powder gas mixture which is fed to the flow passage. Electrodes connected to a high voltage source are provided within the flow passage and at the discharge end of the nozzle to ionize the powder gas mixture. The invention provides a hollow oval shaped charging chamber within the nozzle communicating with the flow passage so that the powder gas mixture passes therethrough and is ionized therein.

Abstract: An electrostatic fuel injector includes a plurality of threadlike tubes for ejecting charged fuel, an accelerator electrode for accelerating the fuel and a control electrode for modulating the amount of fuel ejected. A method for controlling the fuel injector includes applying a control bias to the control electrode with respect to the accelerator electrode in response to an engine operating parameter so as to modulate the amount of fuel in proportion to engine load. A plurality of such fuel injectors is stepwisely operated in response to the engine operating parameter to provide a wide range of variations in fuel quantity.