A rotational atomizer turbine of the present invention is designed to drive a bell-shaped disk in a rotational atomizer for a coating unit. The rotational atomizer turbine includes a housing, a rotatable turbine wheel with several turbine blades connected to a shaft and rotatably disposed in the housing. A plurality of nozzles are defined in the housing and are positioned relative the turbine wheel to drive fluid, i.e. gas onto the turbine blades. An intermediate chamber formed in the housing is fluidly communicated with and connected to the nozzles to hold gas therein. The intermediate chamber has a first inlet to supply gas. At least a second inlet is defined in the intermediate chamber for delivering gas into the intermediate chamber thereby increasing amount of gas therein to multiply a rotational speed of the rotatable turbine wheel as increased amount of gas is introduced to the turbine blades.

A turbine assembly for use with a rotary atomizer rotates an atomizer bell for atomizing paint. A turbine housing is disposed within the rotary atomizer. A locking element is received by the turbine housing. A rotary shaft is rotatably supported within the turbine housing and has a distal end adapted to receive the atomizer bell. The distal end extends outwardly from the turbine housing. The rotary shaft has a proximal end adapted to receive the locking element. The locking element is moveable between a neutral position and a locking position for locking the rotary shaft in a non-rotatable position.

Apparatus for measuring the velocity of shaping air in a rotary bell atomizer for a paint sprayer, including a funnel that collects substantially all of the shaping air, a means for straightening the collected shaping air and a means for measuring the velocity of the straightened shaping air. These techniques enable the average velocity of the shaping air to be calibrated from a single velocity sample.

A powder spray gun includes a rotary distributor which is capable of operating at slower speeds than liquid spray gun to reduce the problem of powder fusing, increases bearing life, reduce wear on moving parts while generating larger fan patterns and optimized charge transfer capabilities. The powder spray gun has a powder flow path which extends through a gun body to a powder outlet. The rotatable powder distributor is located at the powder outlet. A drive mechanism in the form of a motor is located within the housing and connected to the distributor the rotate the distributor. A spindle, which is mounted for rotation within the body, has a passageway therethrough which forms a part of the powder flow path. The distributor communicates with the passageway and is attached for rotation with the spindle. The powder thus enters the passageway in the rotating spindle before it passes into the rotating distributor. A chamber is formed within the body around the spindle, and the chamber is connected to an air supply to pressurize the chamber. A nonrotating flow tube through which powder flows into the passageway in the spindle, with a gap being formed between the nonrotating flow tube and the rotatable spindle. The gap communicates with the chamber whereby pressurized air from the chamber escapes through the gap to provide a rotary seal between the tube and the spindle. A sealing member may be used to prevent back flow of air through the gap.

An electrostatic coating system having a rotary atomizing device formed of a non-conductive body member having an opening in an outer end thereof, a semiconductive member is disposed on a side portion of the body member, a first lip devoid of the semiconductive member is disposed about the opening of the body member proximate the outer end thereof, and a second lip is disposed radially outwardly of the first lip, between the first lip and the inner end of the body member.