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 electrostatic atomizer can include a paint supply path configured to supply paint to a paint discharge section; and a high voltage supply path configured to supply a high voltage to a discharge electrode, wherein the discharge electrode comprises a semi-conductive material, and wherein the high voltage supply path includes a high resistance near the discharge electrode, and is electrically segregated from the paint supply path.

An alternator, such as for use in an electrostatic spray gun, comprises an electromagnetic alternator, a housing and an impeller. The electromagnetic alternator has a shaft. The electromagnetic alternator is disposed within the housing. The housing has an air aperture. The impeller is mounted to the shaft within the housing so as to be aligned with the air aperture. The impeller includes blades having curved leading and trailing edges. In one embodiment, each blade has a curvature so as to be perpendicular to the air aperture across an entire arc over which each impeller blade has a line of sight of the air aperture.

An electrostatic fluid delivery system that is configured to deliver fluid, such as a disinfectant fluid, onto a surface by electrically charging the fluid and forming the fluid into a spray that can be directed onto a surface, such as a surface to be cleaned. The system is powered by a DC (direct current) power system. The device can electrically or positively charge a liquid or gas.

A generator usable in an explosive atmosphere zone, and having a power greater than or equal to 8 Watts, preferably greater than 10 Watts, and an assembly including an electrostatic sprayer for a coating product and the generator.

Exemplary coating methods and coating systems, e.g., for coating the component surface of a component with a coating agent by means of an atomizer in a coating system, for example to paint a body part of a motor vehicle with paint, are disclosed. An exemplary method comprises moving the atomizer over the component surface of the component to be coated, or moving the component in the spray jet, thereby applying the coating agent to the component surface by means of the atomizer. The atomizer may be operated with at least one electrical and/or kinematic operating variable comprising a certain voltage for the electrostatic charging of the coating agent and/or a certain rotational speed of a rotating spray element of the atomizer. In one example, the electrical and/or kinematic operating variable of the atomizer may be dynamically varied during the movement of the atomizer.

A switch mode power supply circuit with high voltage output, an electrostatic spray apparatus and agricultural plant protection apparatus using the same are provided. The switch mode power supply circuit is electrically connected in series with at least a pre-stage power converter and a post-stage power converter. In order to simplify the control, the switch of the pre-stage power converter is omitted, only one switch of the post-stage power converter is adopted to perform synchronous control. Since the multiple sets of power conversion circuits in the previous stage are connected in series, the turn ratio of the transformer in the power converter in the subsequent stage can be reduced. Therefore, the transformer can be miniaturized and the power supply circuit would be more suitable for agricultural plant protection machine and electrostatic spray apparatus.

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).

A paint tank-equipped electrostatic coating device includes a paint tank device which is provided in a housing and supplies paint stored in a paint chamber to a rotary atomizing head through a pint flow path. In addition, the electrostatic coating device includes a tank cleaning flow path which supplies a cleaning flow for cleaning the paint chamber of the paint tank device, and a control unit which performs control of cleaning the paint chamber after the coating by a coating machine is completed until a paint inflow port of the housing is connected to a color change valve unit.

An alternator, such as for use in an electrostatic spray gun, comprises an electromagnetic alternator, a housing and an impeller. The electromagnetic alternator has a shaft. The electromagnetic alternator is disposed within the housing. The housing has an air aperture. The impeller is mounted to the shaft within the housing so as to be aligned with the air aperture. The impeller includes blades having curved leading and trailing edges. In one embodiment, each blade has a curvature so as to be perpendicular to the air aperture across an entire arc over which each impeller blade has a line of sight of the air aperture.