A voltage application device according to the present disclosure includes a voltage application circuit and a control circuit. The control circuit causes the voltage application circuit to alternately repeat a first mode and a second mode. The first mode is a mode that raises a voltage while time elapses, and generates a discharge current by promoting corona discharge to dielectric breakdown. The second mode is a mode that lowers the voltage to cut off the discharge current by causing a load to be in an overload state against the voltage application circuit. This can suppress an amount of ozone generated, while increasing an amount of radicals produced.

An integrated liquidjet system capable of stripping, prepping and coating a part includes a cell defining an enclosure, a jig for holding the part inside the cell, an ultrasonic nozzle having an ultrasonic transducer for generating a pulsed liquidjet, a coating particle source for supplying coating particles to the nozzle, a pressurized liquid source for supplying the nozzle with a pressurized liquid to enable the nozzle to generate the pulsed liquidjet to sequentially strip, prep and coat the part, a high-voltage electrode and a ground electrode inside the nozzle for charging the coating particles, and a human-machine interface external to the cell for receiving user commands and for controlling the pulsed liquidjet exiting from the nozzle in response to the user commands.

An integrated liquidjet system capable of stripping, prepping and coating a part includes a cell defining an enclosure, a jig for holding the part inside the cell, an ultrasonic nozzle having an ultrasonic transducer for generating a pulsed liquidjet, a coating particle source for supplying coating particles to the nozzle, a pressurized liquid source for supplying the nozzle with a pressurized liquid to enable the nozzle to generate the pulsed liquidjet to sequentially strip, prep and coat the part, a high-voltage electrode and a ground electrode inside the nozzle for charging the coating particles, and a human-machine interface external to the cell for receiving user commands and for controlling the pulsed liquidjet exiting from the nozzle in response to the user commands.

This coating system (2) for coating a workpiece (W1) with a liquid coating product, includes an ultrasonic spray head (14) for generating droplets of coating products, an electrode (32A) for generating an electrostatic field (E) between the electrode and the ultrasonic spray head (14) and a high-voltage generator (52) connected to the electrode for supplying the electrode with high voltage. The shape of the electrode (32A) is advantageously configurable on the basis of the geometry of the workpiece (W1).

An integrated liquidjet system capable of stripping, prepping and coating a part includes a cell defining an enclosure, a jig for holding the part inside the cell, an ultrasonic nozzle having an ultrasonic transducer for generating a pulsed liquidjet, a coating particle source for supplying coating particles to the nozzle, a pressurized liquid source for supplying the nozzle with a pressurized liquid to enable the nozzle to generate the pulsed liquidjet to sequentially strip, prep and coat the part, a high-voltage electrode and a ground electrode inside the nozzle for charging the coating particles, and a human-machine interface external to the cell for receiving user commands and for controlling the pulsed liquidjet exiting from the nozzle in response to the user commands.

An integrated liquidjet system capable of stripping, prepping and coating a part includes a cell defining an enclosure, a jig for holding the part inside the cell, an ultrasonic nozzle having an ultrasonic transducer for generating a pulsed liquidjet, a coating particle source for supplying coating particles to the nozzle, a pressurized liquid source for supplying the nozzle with a pressurized liquid to enable the nozzle to generate the pulsed liquidjet to sequentially strip, prep and coat the part, a high-voltage electrode and a ground electrode inside the nozzle for charging the coating particles, and a human-machine interface external to the cell for receiving user commands and for controlling the pulsed liquidjet exiting from the nozzle in response to the user commands.

A method of stripping, prepping and coating a surface comprises first stripping the exiting coating from a surface, using continuous or pulsed fluid jet, followed by prepping the surface by the same fluid jet. The method also provides entraining particles into a fluid stream, if desired to generate a particle-entrained fluid stream that is directed at the surface to be stripped and prepped. The particles act as abrasive particles for prepping the surface to a prescribed surface roughness required for subsequent application of a coating to the surface. The method then entails coating the surface by electrically charging particles having the same chemical composition as the particles used to prep the surface. Finally, a charged-particle-entrained fluid stream is directed at high speed at the charged surface to coat the surface. The particles form both mechanical and electronic bonds with the surface.

A method of stripping, prepping and coating a surface comprises first stripping the exiting coating from a surface, using continuous or pulsed fluid jet, followed by prepping the surface by the same fluid jet. The method also provides entraining particles into a fluid stream, if desired to generate a particle-entrained fluid stream that is directed at the surface to be stripped and prepped. The particles act as abrasive particles for prepping the surface to a prescribed surface roughness required for subsequent application of a coating to the surface. The method then entails coating the surface by electrically charging particles having the same chemical composition as the particles used to prep the surface. Finally, a charged-particle-entrained fluid stream is directed at high speed at the charged surface to coat the surface. The particles form both mechanical and electronic bonds with the surface.

An electrostatic atomizer electrostatically atomizes a fluid into a charged spray, wherein the charged spray includes a plurality of charged droplets. The electrostatic atomizer includes a chamber forming an inlet and an exit aperture, wherein the chamber is configured for fluid to flow into the chamber from the inlet and to flow out of the chamber from the aperture. An emitter electrode is in liquid contact with the fluid in the chamber and injects an electrical charge into the fluid in the chamber. An impedance circuit is coupled to the chamber and configured to obtain a voltage difference between the emitter electrode and the exit aperture, wherein the voltage difference is at least a minimum voltage threshold.

An electrostatic atomizer electrostatically atomizes a fluid into a charged spray, wherein the charged spray includes a plurality of charged droplets. The electrostatic atomizer includes a chamber forming an inlet and an exit aperture, wherein the chamber is configured for fluid to flow into the chamber from the inlet and to flow out of the chamber from the aperture. An emitter electrode is in liquid contact with the fluid in the chamber and injects an electrical charge into the fluid in the chamber. An impedance circuit is coupled to the chamber and configured to obtain a voltage difference between the emitter electrode and the exit aperture, wherein the voltage difference is at least a minimum voltage threshold.