| 摘要 |
The spraying method is achieved using a spray head (11) which receives liq. paint from a reservoir and compressed air using two supply lines (12,13). The head includes a conical bell (14) rotated about its axis (15). Liq. paint is fed to the surface of the bell and flows along the surface to the outer edge (16) from which it is thrown under centrifugal action to form a cloud of paint droplets. In the absence of any external influence the cloud would be planar and at right angles to the axis. However, either in one supply line (12) or within the head, the paint receives a high voltage electrostatic charge so that the droplets in the cloud are highly charged and electrostatically attracted to an earthed target (17) positioned in front of the head. - The cloud leaving the edge of the bell migrates towards the workpiece by virtue of the electrostatic attraction. In order to confine the cloud migrating towards the workpiece, the fixed part of the head is provided with air jets (18) presented towards the target and arranged in a circular row concentric with the axis of the bell. Air from the supply issues from the jets and defines an air shroud containing the cloud and also guiding the cloud towards the workpiece. |
