GB817184A - Apparatus for abrasively surfacing continuous webs - Google Patents

Abstract

817,184. Cleaning metals. TRU-SCALE Inc., and PELLEY, P. H. Dec. 5, 1956 [Dec. 8, 1955], No. 37233/56. Class 82(2) [Also in Group XXIII] Apparatus for abrasively treating a surface of a continuous web 2, e.g. of copper or aluminium, comprises an enclosed cabinet 5, means for feeding the web thereinto, windup means 16 adapted to draw the web through the cabinet, a back-up bolt 18 within the cabinet above the web having a downwardly arcuately disposed lower run which is adapted to be moved together with the web without any relative movement therebetween, idler rolls 24, 26 at each end thereof and under the web, means within the cabinet disposed to hurl abrasive granules against at least a portion of the lower surface of the web supported by the arcuately disposed run and at an acute angle to the surface, and cleaning means 12 for removing residual abrasive granules from surfaces of the web. The web is taken from a roll 8 provided with drag or brake means to resist unwinding of the web therefrom so as to tension the web; wind-up roll 1 may be driven by an electric motor through a variable speed drive. The downwardly arcuate path of the lower run of the back-up belt 18 is caused by a shoe 21 or by a plurality of shoes independently adjustable vertically; the upper run of belt 18 may be supported by a shoe 22. The belt 18 is preferably made of rubber reinforced with cotton or rayon. Two throwing wheels 28, 30 are located below the belt 18. The housing 5 has a grating floor 34 and a hoppered bottom 36 extending downwardly into a pit in concrete base 37; the hoppered bottom 36 opens into the lower end of flight elevator 38 which raises spent abrasive and dumps it into screw conveyer 46 which carries it to cleaning chamber 48. Impurities removed by screening devices are carried by the screw conveyer into chamber 50 and then fall through tube 52 into a receptacle. Clean abrasive granules fall into hopper 54 and thence pass downward through metering devices into tubes 56, 58 feeding the granules into the hubs of wheels 28, 30. Any granules which have lodged on the upper surface of the web are removed by air supplied by blower 43 to a cleaning nozzle 42. The air introduced into the cabinet 5 by nozzle 42 passes downward through grating floor 34, upward through elevator 38 and thence outward through duct 60 into cyclone seperator 62 and thence through tube 64 into blower 66. From the latter air passes downward through duct 68 into device 70 where light-weight dust is filtered from the air; heavier dust removed in cyclone separator 62 passes downward through tube 63 into cabinet 5 from whence it may be recycled. Within cleaning chamber 48 a current of air passes through a cascade of abrasive falling therefrom into hopper 54 and relatively light-weight dust is thus removed from the abrasive granules and caused to be suspended in the air which passes thence through duct 69 into device 70. The cleaning apparatus 12 for removing any adherent granules includes a rotating brush 71 operating against back-up roll 72, rotating brushes 77, 78 immersed in washing solution 74 in tank 73, and a tank 75 containing clean rinsing water. The drier 79 consists of radiant electrical resistance elements 97 with reflectors 98; alternatively an oven or tunnel with a through flow of hot air, a gas-heated oven or other drying means may be used. Instead of using throwing wheels, the granules may be projected by air, steam, water or a mixture of water and steam.