seen and machine for treatment of a surface by means of blestermedelspartiklar which is thrown to the surface

摘要

1496268 Blasting WORLDWIDE BLAST CLEANING Ltd 29 Sept 1975 [21 April 1975] 39770/75 Heading B3D A method of treating a surface 3 comprises projecting abrasive particles 7 at an inclined angle relative to the surface to abrade the surface and to cause the particles to rebound from the surface, and striking the rebounding particles 9 to throw said particles along a predetermined path 12. An apparatus for carrying out the method has an enclosure 1 formed with an opening 2 which faces the surface 3 to be abraded and has a resilient seal 6. A centrifugal blast wheel 4 projects a stream of particles 5 towards the surface at an inclined angle of between 10 and 60 degrees. The particles rebound along a path 10 and are propelled by an anticlockwise rotating brush 11 along a path 12 to a further clockwise rotating bush 13 which propels the particles along a path 15 to a hopper 14 for feeding the blast wheel 4. Rotating paddles may replace the brushes. The enclosure is made of thin gauge steel or aluminium and the housing 18 for the blast wheel is lined with manganese steel, cast alloy or hardened plate. The abrasive particles may be metal shot, slag, sand, volcanic ash, glass beads, metal oxide particles, zircon, garnet, carborundum, stone, &c. The brushes or paddles 11, 13 are driven by a belt or chain drive 25 from a drive sprocket 19, the lower brush 11 rotating at a higher speed than the upper brush 13. Three or more brushes may be arranged in series. The lower brush may contact the surface 3 or be, as shown, spaced therefrom. The resilient seal 6 may have a portion 28 adjacent a rear zone 27 of the opening formed as a resilient brush to permit the entry of fluid 29, such as air, to the rear zone 27 to remove abrasive particles which may accumulate in the zone. The air flow 29 may be produced by vacuum and proceed along paths 10 and 15. The spent abrasive falls into the hopper and foreign material proceeds along path 31 into a trough 34, where any entrained abrasive particles fall through an adjustable gate 35, the air and remaining foreign material passing along a path 36 to a dust collector. The apparatus may have a steering handle, one or more drive wheels 39 and a front castor wheel assembly 40 and operate on horizontal or vertical surfaces. The apparatus may remain stationary and treat a surface moving past the opening.