| 摘要 |
<p>1530508 Electrostatic powder-spray coating VOLSTATIC COATINGS Ltd 11 May 1977 [27 May 1976] 22072/76 Heading B2L Powder spray apparatus comprises a tubular enclosure 11 having spaced therealong an inlet and an outlet 19 for gaseous medium, means 21 for injecting powder into said enclosure adjacent said inlet whereby to form a powder cloud, means for moving the cloud to said outlet, and an insulating surface 11a in the enclosure between the inlet and outlet and surrounding objects 15 to be coated, which serves to triboelectrically charge powder, which is attracted to objects 15 to coat them. As shown, objects are conveyed through enclosure 11 and are earthed; powder is injected at 21 and air is supplied through slots in the chamber ends; triboelectric charging is reinforced by point electrodes 22 connected to a voltage source; deposition of powder on chamber floor 26 is inhibited by air from blowers 28 permeating floor 26. Air and over sprayed powder are removed at 19 and separated in cyclone 20; the powder is recycled to 21. After coating, the objects are heated to cure the coating.</p> |
