摘要 |
<p>An improved electrostatic spray gun for the deposition of powdered coating material on a workpiece is disclosed. The spray gun includes a housing having a barrel to which a nozzle is attached for directing the powdered material to the workpiece. A charging electrode which is connected to a high voltage power supply, is mounted on a diffuser assembly which is clamped between the nozzle and the housing, on which the nozzle is threaded. A regulated gas flow supplied through the housing and the diffuser assembly provides a gas shield around the charging electrode to prevent a buildup of the coating material on the electrode. A novel pneumatic safety interlock continuously monitors the pressure of the gas supplied to the diffuser assembly. The interlock turns off the high voltage power supply and a pump for the coating material in response to a drop in such pressure resulting from a loose nozzle.</p> |