Abstract:
A system, in certain embodiments, includes a nozzle. The nozzle includes a liquid passage, a first pneumatic passage, and an exit surface. The exit surface includes at least one recirculation inducing feature configured to reduce deposits adjacent to the first pneumatic passage.
Abstract:
An apparatus for spraying and inducing an electrostatic charge upon a liquid in excess of 0.8 millicoloumb/kilogram is connectable to a boom fitted to a vehicle, such as an aircraft, having a dc power supply. The apparatus comprises a nozzle constructed from a substantially non-conductive material and includes a spray tip designed to provide a hollow conical spray pattern. A support member extends from the nozzle and supports a charging electrode for inducing an electrostatic charge upon the liquid sprayed through the nozzle. The charging electrode attaches to the support member and is electrically connectable to the dc power supply. The charging electrode includes a cylindrical portion and a plurality of corona discharge members extending inwardly from a distal end of the cylindrical portion adjacent to the spray tip. The charging electrode is positioned to permit the hollow conical spray pattern to pass unhindered therethrough.
Abstract:
An atomizer has a chamber holding a liquid containing particles of a desired material. Aerosol particles are formed by using an aspirating nozzle or ultrasonic vibrator and the aerosol particles are carried in a gas flow. The aerosol particles are treated by increasing the charge on the aerosol particles by contact with a high voltage electrode and the aerosol particles are passed through inertial separator stages to remove large aerosol particles from the flow so they are not discharged from the atomizer.
Abstract:
Air atomizing induction charging spray nozzles suited for use with conductive liquids, solutions, suspensions or emulsions. These systems feature a high level of the spray charging at low induction--electrode voltage and current. Primary benefits include consistent, reliable operation in harsh agricultural and industrial environments with a wide range of spray formulations, especially those having relatively high concentrations of abrasive and conductive materials. Internal and external surfaces are configured to minimize potential differences between electrode and ground. Such nozzles may employ external cavities, field concentrators, hoods and other structures and arrangements to affect aerodynamic flow of gases within the vicinity of the nozzles and electrostatic and electrodynamics effects such as those caused by electrical fields within the vicinity of the nozzles.
Abstract:
Particles of spray solution are given with an electrostatic charge by applying voltage of 300 to 800 V thereon as the solution passes through the tip of the spray nozzle of an electrostatic spray dispenser. The tip of the spray nozzle is separate and adjustable with respect to the nozzle and has on its inner surface the electrode
Abstract:
A tribo-electric powder spray gun includes a diffuser for mixing powder with a conveying gas, a charging portion downstream of the diffuser, and a sprayhead at the outlet of the charging portion for dispensing the charged powder. The charging portion has an inner core removably positioned within a hollow outer cylinder with an annular gap formed between the outer cylinder and inner core providing a charging flowpath for the powder. The inner core and the outer cylinder have undulating or wavy charging surfaces made of an electrically insulating material, so that the annular gap provides a tortuous path for the powder, enhancing powder contact and the charge imparted to the powder. Grounding is provided by surface conduction of the electrically insulating contact material through a ground ring located outside the powder path at the inlet to the charging portion of gun where the greatest amount of charging occurs. By locating the ground ring outside the powder path, the ground ring is kept clean and the amount of charging surface is maximized. The inner core and the outer cylinder are longitudinally symmetrical to facilitate re-assembly.
Abstract:
A spray arrangement including means to form and direct a spray of liquid droplets and means to apply an electrostatic charge to droplets in said spray, said charge applying means including an insulating body to support a spray-charging electrode in association with the spray-forming means, the spray-forming means [10] forming the spray hydraulically, the body [20] having a smoothly-constricted bore [26, 27, 28] for the free passage of spray with the electrode [23] housed to expose only inward-facing electrode surface [28] as the constriction to passing spray [40] for the acquisition of charge therefrom, the bore surface turning back upon itself [29] as it expands beyond the constriction to form an end of the body, the end of the body where the surface turns back upon itself [29] and the part of the bore remote from said end being formed to assist the shedding of liquid [22, 51, 52]. The arrangement is suitable as a dairy sprayer to direct charged spray upwardly from said turned-back end on to the teats and udder of a dairy animal such as a cow, ewe or goat.
Abstract:
A device for electrostatically charging and dispensing a high resistivity cutting lubricant to a workpiece includes a source of high resistivity cutting lubricant and a capillary tube having an entrant end in fluid communication with the high resistivity cutting lubricant and a tapered discharge end forming a sharp point. A high voltage power supply is used for generating a high voltage of less than 5,000 volts d.c. The power supply has a positive terminal and a negative terminal. A high voltage electrode has its one end connected to the positive terminal of the power supply and has its other end operatively coupled to the discharge end of the capillary tube. A nearby grounded electrode is disposed in a spaced-apart relationship from the discharge end of the capillary tube so as to create a high electric field therebetween for electrostatically charging the lubricant. The lubricant is atomized and projected in the form of a steady and controlled stream of charged particles away from the discharge end of the capillary tube to within the vicinity of or all the way to the workpiece before the stream of charged particles bursts into an aerosol cloud of charged droplets for dispensing them onto the workpiece.
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:
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.