| 摘要 |
<p>Closed-circuit blasting apparatus comprises a plurality of turbine blowers (21, fig. 4) arranged side-by side, a reservoir 19 for blast medium, a cyclone 16 for separating used blast medium and feeding it into the reservoir 19, all mounted in a hand portable housing. A filter 18 lies between the cyclone 16 and the turbines. By using a variable air inlet (263, fig. 4) for the turbines the action of the cyclone 16 can be controlled. The turbines may be mounted in a dome (24, fig. 4) removably attached to the remainder of the housing. Rotation of the dome alters the amount of air entering the turbines. Air is supplied by the blowers to a hand tool having a Venturi device to entrain the blasting medium. A brush mounted on an elastic collar surrounds the exit of the hand tool. The blast medium may be pellets of non-woven fabric, some of which are impregnated with a substance (e.g. polish) which transfers to the workpiece upon impact. Also disclosed is a shoulder mounted recycling container (figs. 6 and 7).</p> |
