A fluid stud and resistor design for electrostatic spray guns has a fluid passage which is shaped like a cloverleaf in cross section. By providing this cross-sectional shape, the resistor is allowed to reside in one wall of the fluid stud and run, nearly, the complete length of the stud, thereby providing an increased effective resistor length, thus reducing flash-over and providing a smaller contact wire, thereby reducing capacitance. The design of the fluid needle and electrode is provided so as to reduce the length of the electrode wire, thereby reducing capacitance and allowing an increased diameter wire for increased durability.

A method and apparatus are provided to regulate the flow of compressed air and steam utilized in treating spots in cloth or clothes with a spotting table having a spotting gun. The method comprises first turning on the steam or compressed air of the spotting table using conventional foot valves and next throttling the steam or compressed air flow to a desired level by manipulating a valve provided on the spotting gun, which valve can be manipulated and set by the spotting gun operator with the same hand holding the spotting gun.

An air atomizing nozzle assembly for electrostatic spray guns is disclosed. The nozzle assembly is made of plastic parts and includes an air cap having a central bore which surrounds a fluid nozzle tip. The nozzle has a nut formed on its forward end to facilitate threading of the rearward end of the nozzle tip into a threaded bore of the gun body. Formed on the front part of the nozzle, either as a part of the nut or a cylindrical surface adjacent the nut, is an accurately machined surface engageable in press fit relationship with a mating accurately machined bore of the air cap. These mating press fit surfaces center the bore of the air cap relative to the nozzle tip so as to leave an annular, evenly dimensioned air flow passage surrounding the nozzle tip and defined between the nozzle tip and the bore of the air cap. The air cap is retained in a one-piece resilient retaining ring by snapping the air cap into an annular lip of the retaining ring. The retaining ring is then threaded onto the gun body to secure the nozzle assembly onto the gun body.

An improved control shaft seal and air valve for a portable paint gun with the seal having a radial clearance with the shaft except at a shaft sealing surface of limited axial length. The shaft seal has a conical surface radially outward of the shaft sealing surface to provide a sealing surface and also to provide transfer of axial forces at that surface to a radial direction to provide a force to urge the shaft sealing surface against the control shaft. A second conical surface of the seal provides for retention of the seal on an air valve spring when the paint gun is disassembled. An improved air valve for portable paint guns is also disclosed having a rigid axial hub and radial support carrying a relatively flexible rim portion adapted to engage a tapered seating surface in the gun.

An improved control shaft seal and air valve for a portable paint gun with the seal having a radial clearance with the shaft except at a shaft sealing surface of limited axial length. The shaft seal has a conical surface radially outward of the shaft sealing surface to provide a sealing surface and also to provide transfer of axial forces at that surface to a radial direction to provide a force to urge the shaft sealing surface against the control shaft. A second conical surface of the seal provides for retention of the seal on an air valve spring when the paint gun is disassembled. An improved air valve for portable paint guns is also disclosed having a rigid axial hub and radial support carrying a relatively flexible rim portion adapted to engage a tapered seating surface in the gun.