Airless spray gun having improved nozzle assembly and electrode circuit

Abstract

A spray gun for airless atomization for electrostatic deposition of a coating material upon a substrate includes a novel dual electrode element having a spring loop portion. The two electrodes are the respective end portions of a single electrode wire, which has its major portion between the electrodes formed into a spiral spring. A tip resistor is provided with a conductive fitting that presents a broad and sturdy bearing surface which abuts the electrode spring portion to thereby directly connect the electrode with a high voltage charging circuit. The electrode spring accommodates spacing variations between the electrode and tip resistor, and provides a continuous electrical connection regardless of the rotational position of the electrode relative to the tip resistor. The dual electrode spring further serves to secure a number of otherwise loose parts of the gun nozzle assembly together, and prevents the parts from falling out and getting lost when the nozzle assembly is removed from the spray gun. An improved electrical circuit is also achieved through the use of a conductive cap which surrounds one end of a high voltage barrel resistor used in the gun. The conductive cap has a portion which extends along the barrel resistor body which is electrically connected to the tip resistor by a spring lead from the tip resistor.