Abstract: Electrically charging liquid droplets by causing a liquid sheet to expand in area and to break up into droplets in a region adjacent to an electrode.

Abstract: The electrostatic nozzle may be used to spray one or more charged clouds in different areas of an enclosed room to allow different materials to be deposited on different sections of the surfaces. The nozzle includes a conduit through which air passes over one or more airfoils to entrain a liquid across the surface. A charged electrode, facing the surface, inductively charges the liquid on the surface. The liquid is atomized at the trailing edge of the airfoil by a cross-current created by an air deflector near the trailing edge of the airfoil.

Abstract: The electrogasdynamic coating system includes an electrogasdynamic gun for charging material particles indirectly. The gun has a gas inlet which receives from a gas source a pressurized gas in which an condensable vapor is entrained. Corona and attractor electrodes are disposed in communication with the gas inlet for ionizing the ionizable vapor. A dielectric tube extends from the electrodes downstream to a mixing chamber. A first fluid material inlet is connected with a first source of powder or liquid material and a second fluid material inlet is connected with a second source of powder or liquid material. The first and second fluid material inlets are connected with the mixing chamber such that particles of the first and second fluid materials are mixed with the gas and vapor. The vapor condenses and coats the particles during mixing causing them to become charged. In use, a condensable vapor is entrained into a gas flow, the gas flow is passed across corona and attractor electrodes to ionize the vapor.

Abstract: An electrostatic air atomization spray coating system having a hand held spray gun, wherein a flow of air to the gun is sensed to control energization of a high voltage power supply for electrostatically charging spray particles, is characterized by a bypass valve on the spray gun which selectively permits air atomization spraying with or without electrostatics.

Abstract: The invention relates to a device for a nozzle of a powder sprayer, which by way of example can be used for spraying for example color powder, which is electrostatically charged, or for disintegration and distribution of solid particles in powder form transported in a gas stream. By means of the present device, which is easy to operate and easy to connect with a transportation circuit respectively, the particle material is effectively disintegrated and distributed. The device has means (17; 51, 58, 75, 76) for the introduction of a gas stream under pressure in the stream of particles flowing through the device, whereby the powder during its forward transportation through the device under simultaneous compression is mixed with the gas rushing in.

Abstract: A nozzle assembly for an electrostatic powder spray gun is disclosed. The powder spray gun includes an electrically non-conductive barrel through which a high voltage electrical path passes. The nozzle assembly is mounted in the open forward end of the barrel and includes a sleeve located on the center axis of the barrel for directing a flow of a pressurized gas, e.g., air, through the center of the nozzle assembly, a nozzle surrounding the sleeve defining an annular flow path for powder spray coating material encircling the flow of pressurized air and an air deflector cap for directing the pressurized air radially outwardly and into the flow of powder spray coating material being emitted from the nozzle. The air impacts the powder coating material to form a conical spray pattern of coating material. The gun also includes an electrode extending out of the nozzle assembly for electrostatically charging the powder. The nozzle assembly eliminates mechanical powder deflectors and the problems attendant therewith.

Abstract: A method of spraying electrically charged particulate material to ground from a low flying airplane. The method includes the steps of imposing an electrical charge of given polarity upon an emitted primary spray of particulate material of sufficient magnitude to electrostatically enhance the deposition thereof and concurrently emitting a secondary spray of oppositely charged particulate material of selective character from said airborne source at a charge level of a magnitude to avoid material degradation of the charge on said primary spray intermediate its loci of emission and deposition.

Abstract: A device for painting by electrostatic powder spraying including a nozzle member having a passage to which spray powder particles are supplied in a wafting state in air and in which the particles are triboelectrified. The nozzle member is provided with powder discharge windows from which the electrified powder particles are discharged and diffused by a diffuser. The inner wall of the nozzle passage, the peripheral walls of the windows and the surface of the diffuser are covered with fluorocarbon resin of a low friction coefficient.

Abstract: A method of generating a vapor stream is disclosed which comprises the steps of providing a jet of electrostatically chargeable liquid particles and electrostatically controlling the jet so as to meter some of the liquid particles into a vaporizer for a period of time sufficient to become vaporized.

Abstract: A method and apparatus are disclosed for spray coating one or a series of objects with at least two powder coating materials in succession or alternately. When a change of the material being sprayed is to be effected, the flow of the first material is terminated, preferably by means of a squeeze valve, the flow path of the first material is flushed with a fluid, preferably air, and the second spray material is sprayed. The relative positions of the apparatus forming the respective flow paths of the two spray materials are not changed during this process. In one preferred embodiment, feed conduits corresponding to respective spray materials converge into a single delivery conduit. Each feed conduit includes means for closing and opening it. Means are provided for flushing at least part of a given feed conduit, or the delivery conduit, or both, with a fluid. The flushing can preferably be done pulsatingly.

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

Abstract: An electrostatic powder coating system for selectively spraying any one of a plurality of different pulverant powder materials from a common spray gun without the necessity for physically disconnecting or reconnecting the spray source of the different pulverant materials to the common gun. This system includes the common spray gun, a plurality of powder material reservoirs and associated venturi pumps connected to a common manifold block. That manifold block is also connected to a source of purging air flow. Internally of the manifold block there are pinch valves operable to selectively connect and disconnect each of the different powder material reservoirs and the purging air flow to the common spray gun. Additional pinch valves separate the material reservoirs from the venturi pumps associated with each reservoir.

Abstract: A liquid atomizing and spraying device which can be operated with a relatively low air pressure. The spraying device has three coaxial tubular passages; an inner one for air, an intermediate one for liquid, and an outer one for air; which are shaped to have the liquid ejected as a thin film having a divergently conical shape which is caused to vibrate by the air which is being ejected in a vortex flow for generating cusps on the film in an electrostatic field for being finely atomized and projected.

Abstract: A device for moistening and discharging electrically insulating objects, comprises, an atomizer for atomizing a liquid, such as water, into a spray and for directing the spray through a path and onto the object. The spray is directed through a path which is provided with an electrode charger or a group of chargers arranged in a pattern for charging the spray particles with a charge opposite to the object so that when they contact the object, they discharge the object as well as moisten it. The device is usable in the printing industry by passing a paper web which has been either previously printed or will be printed through a path after it has been charged with a charge, such as a positive charge, and then directing a spray onto the web after the spray moves through a series of electrodes to impart an opposite charge to the spray particles from that of the paper, so that the particles both moisten the paper and discharge the charge therefrom when they are directed thereto.

Abstract: A powder feed device for supplying a powder dispensing apparatus such as a powder spray gun of an electrostatic powder deposition system. Entrained powder is extracted from a fluidization tank and transported through a half-inch diameter tube or hose to the dispensing apparatus. To prevent clumps of powder and/or powder adhering to the walls of the tube or hose while permitting reduced air flow speed of about 2 to 3 m/s an electric field is provided in the tube or hose and applied by an outer conductor extending around the tube or hose and an inner wire conductor inside the tube or hose extending in the direction of the flow of entrained powder, which conductors are connected across an AC voltage source. The electric field may operate constantly or intermittently.

Abstract: An electrostatic, coating-dispensing apparatus includes an electrode upon which an electrostatic potential is impressed. The electrostatic potential is developed by a switching circuit, autotransformer and voltage multiplier from rectified line voltage. The entire apparatus is housed in a hand-held applicator to which line voltage is supplied. The apparatus includes a socket defined at one end thereof for interchangeably receiving containers holding various colors or types of coating material. Each container includes an electrode for contacting the first-mentioned electrode. The containers are shaped to fit snugly into the socket to hold the two electrodes in contact. An outer end wall of each container has a mesh portion through which charged particles of coating material from the interior of the container pass when the apparatus is activated.