An electrically isolating pressure feed paint reservoir suitable for holding electrically conductive paint applied with an electrostatic spray gun. A paint container is located in an electrically insulated housing which is mounted on a dolly for portability. The housing also mounts a pneumatically operated paint pump for delivering pressurized paint to the spray gun. When a lid to the housing is removed the high voltage power source is turned off and any high voltage present in the housing is discharged through a resistor.
A grounded insulated electrostatic supply tank comprised of a conductive tank that has several liners to fully insulate a waterborn fluid in the tank from ground. The interior of the tank and a sealed lid are coated with an insulating liner. An intermediate lining is placed in the tank and third interior insulating inner liner is inserted in the tank and has a lip that wraps around the upper rim of the tank and is sealed between the lid and the tank. Electrostatic spray equipment is connected to the tank by a coaxial hose having an inner non-conductive hose and preferably, an outer hose that is conductive. Inner non-conductive hose extends through the lid into an insulating teflon pick-up tube that extends to near the bottom of the tank. Depleted waterborn fluid in the tank is grounded after use by a manual probe or by a piston operated automatic grounding system.
Apparatus for spraying an ice surface with a white paint comprises a trailer having a tank carried on the trailer, a pump and a boom having a plurality of spray nozzles. The tank has a large opening in the top for receiving bags of paint pigment. The pump is a high capacity pump which generates a flow rate significantly greater than necessary to supply the nozzles. The excess is returned to the tank through a jet mixing system including four arms each having a pair of jet nozzles. A mixing wand is also provided which receives mixed materials from the pump for the jet nozzle for stirring within the tank. The nozzles are closely spaced so as to generate an overlapping spray pattern. The nozzles generate a fine mist and are directed slightly upwardly and rearwardly.
An electrostatic spray coating device for electrically conductive, non-combustible coating fluid. The coating fluid is accommodated in a pressure container (2) of electrically insulating plastic and connected over a tube (10) of electrically insulating material with a spraying device (8). An electric conduction path (53) heads off high voltage from the coating fluid (6) which is present in the pressure container (2) when the high voltage is switched off. Thereby the electrical capacitance of the device is reduced and simultaneously it is ensured that after the switching-off of the high voltage the coating fluid present in the pressure container (2) in a few seconds is no longer electrically charged. Thereby, immediately after the switching-off of the high voltage, the pressure container (2) can be opened, for example for the replenishing of coating fluid.
An electrostatic spray system has a high voltage section where an electric charge is applied to a liquid and the high voltage section is isolated from a lower potential section, such as a frame. The spray system has components on the high voltage section that communicate for operating functions with other components on the low voltage section, such as a liquid level sensor that controls flow into a liquid reservoir or valves on the high voltage section controlled from the low voltage section. Radio controls are provided for the components so there are no physical links for the operation of the components that can provide current leakage paths back to ground.
An apparatus for transferring electrically conductive coating material comprises a filling station having a first coupling element connected to a source of the coating material and a shuttle carrying a second coupling element which is movable with respect to the filling station between a paint transfer position in which the coupling elements engage and a neutral position physically spaced from the filling station. The shuttle, in turn, is connected to the reservoir of a piston pump which communicates with one or more air operated or air assist spray guns. A high-voltage power supply is connected to the metal body of the piston pump to charge the electrically conductive coating material immediately before it is supplied to the spray gun. A pneumatic/mechanical control system controls the operation of the shuttle, pump and electrostatic power supply to ensure that a voltage block is maintained between the source of coating material and the electrostatically charged coating material which is discharged from the spray gun.
