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. A new air valve seal assembly is also provided. The modular gun design can accommodate electrostatic and non-electrostatic versions.
Abstract:
A coating-powder spray gun includes a gun housing (2) of which the front end face is sealed pressure-hermetically with respect to compressed gas by a front end wall (28). A current-limiting resistor (32) and at least a portion of a high-voltage generator (10) are potted in an integral electrically insulating block. The potted block may be received in the gun housing (2).
Abstract:
A powder spraying gun generates a desired pattern of electrostatically charged particles for coating a workpiece without rotating parts or particle deflectors. The powder pattern is generated with a funnel-shaped output in conjunction with air introduced into a powder charging chamber of the gun in a tangential swirling motion. The swirling air is additionally used to purge agglomerated powder particles from the charging electrodes in the charging chamber. The charging chamber surface is fashioned from material exhibiting low friction or high resistance to powder impact fusion.
Abstract:
A corona charge spray gun for dispensing powders for powder coatings. The spray gun includes a housing defining a chamber terminating in an outlet passageway. A high voltage electrode is mounted in the chamber spaced upstream of the outlet passageway and a ground electrode is mounted in the chamber spaced upstream from the high voltage electrode. The ground electrode is selected to have a surface area sufficiently larger than the surface area of the high voltage electrode in order to allow high voltages to be applied to the high voltage electrode without arch discharging occurring in the chamber. An inlet opens into the chamber for conducting a powder-gas mixture into the chamber and the electrodes receive cleaning gases for avoiding powder deposits on the electrodes.
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. The atomized liquid then passes through an electrode, which is electrically charged by the high voltage signal to form an electrostatic spray. The electrical charge in the spray leads to better dispersal of the spray due to the droplets in the spray repelling from each other, and further improves the adherence of the spray to crops which attract the charged droplets.
Abstract:
A method of introducing biological material into cells includes providing one or more target cells and establishing a spray of substantially dispersed particles including biological material. The substantially dispersed particles have an electrical charge applied thereto such that one or more of the substantially dispersed particles of the spray is introduced into one or more of the target cells. The spray of substantially dispersed particles may be established by dispensing a spray of microdroplets suspending particles. The electrical charge is concentrated on the suspended particles as the microdroplet evaporates. The suspended particles may include carrier particles with biological material or the suspended particles may be particles of biological material alone. The space charge effect of the concentrated electrical charge on the substantially dispersed particles of the spray enable one or more of the particles to be introduced into one or more of the target cells.
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. The atomized liquid then passes through an electrode, which is electrically charged by the high voltage signal to form an electrostatic spray. The electrical charge in the spray leads to better dispersal of the spray due to the droplets in the spray repelling from each other, and further improves the adherence of the spray to crops which attract the charged droplets.
Abstract:
A high voltage generated by a high voltage generator is applied to corona electrodes, and powder supplied from a powder flow passage collides against a diffuser main body while being moved in a vortex by air ejected from a vortex air introduction port and is ejected from a nozzle opening. After the powder is charged by ions generated by corona discharge, it is sprayed to an object to be coated. Free ions generated by the corona discharge are trapped by ion trap electrodes. The adhesion of the powder can be prevented by the ejection of compressed air through a diffuser front portion cover and an outer cylinder cover each composed of a porous member and the ejection of compressed air from a nozzle hole.
Abstract:
A powder spray coating system includes a spray gun for spraying powder in a spray pattern onto a part. The spray gun includes an electrode connected to a power supply, the electrode charging powder as the powder is dispensed from the gun toward the part. A first current sensor measures gun current from the power supply to the electrode. An ABI probe or ion collector is mounted with the gun for collecting free ions produced by the electrode. The collector has a forward portion positioned near the spray pattern and spaced from the electrode. A second current sensor measures return current from the ion collector. A regulating assembly regulates the return current from the ion collecting device. A controller is connected to the first and second current sensors and to the regulating assembly for operating the regulating assembly in accordance with a predetermined setting representing the difference between the gun current and the return current. The system automatically adjusts the position or effective position of the forward tip of the ABI probe relative to tip of the gun as parts of different shapes and geometry pass before the gun.
Abstract:
A multiple charged developing gun provides a multiple charged electrode portion comprising a body and a flow path that is formed in an inner portion of the body and through which powder flows; an entrance, which is formed on one side of the body, connected to the flow path, and in which the powder flows through a powder supply line by being connected to a powder supply apparatus; an exit that is formed on the other side of the body, which is connected to the flow path that becomes gradually narrow; a multiple charged electrode portion that is disposed in an inner portion the body, which is near to the exit; and a cable, which connects the multiple charged electrode portion to a power supply apparatus. The multiple charged electrode portion comprises an electrode supply assembly, which is disposed in an inner portion of the body; a multiple electrode on which plural strip type electrodes is arranged at the electrode support assembly in forming a line toward the longitudinal direction of the body and the multiple electrode is connected to a power supply apparatus through the cable.