GB1011949A - Centrifugal wheel blasting machine - Google Patents

Abstract

1,011,949. Blasting. VACU-BLAST Ltd. Oct. 27, 1964, No. 43864/64. Heading B3D. [Also in Division F2] An abrasive blasting machine comprises a rotatable wheel having a plurality of vanes extending radially outwardly from an open space around the axis of the wheel, a collecting hopper for the spent abrasive thrown from the wheel, a main conduit communicating at one end with the open space of the wheel, open at its other end to a source of air and adapted to receive abrasive material from the collecting hopper and entrain the abrasive in an air stream and convey it through she conduit towards the wheel, a separator connected in the main conduit above the wheel, to remove the abrasive from the air stream in the main conduit, means for moving a stream of abrasive from the separator to one side of the open space within the wheel, means for driving the wheel and means for dispersing the abrasive radially outwardly into contact with the wheel vanes, whereby the abrasive is admitted to the wheel free from the influence of the air from the main conduit being sucked into the wheel and is centrifugally propelled by the wheel vanes into a predetermined work area. A wheel 11 driven by an electric motor 17 controllable to give the desired speed, e.g. 10,000 R.P.M., throws abrasive particles through an opening 33 in the top of a cabinet 12 on to the workpiece which is supported by a rotary table 35 having an expanded metal or wire screen 38. The table 35 and its driving motor 41 are carried by a door 40 of the cabinet. Spent abrasive falls through a grate 44 into a hopper 14 having an orifice 47 communicating with a duct 48. The lower end of the duct 48 is connected to an opening 49 near the upper end of the hopper 14; alternatively it can be open to atmosphere or any other source of air. The upper end of the duct 48 is connected to the inlet of a cyclone separator 15, the top of which is connected by a duct 30 to a member 28 leading into the central space of the wheel 11. The suction in this central space causes spent abrasive from the hopper 14 to be conveyed pneumatically to the separator 15. Abrasive particles from the bottom of the separator pass, under the control of a manually operated valve 55, into a tube 29 projecting through the member 28 into the central space of the wheel 11. The end of the tube 29 in the central space has a radial opening 31 and the other end of the tube is connected by a pipe 32 to the cabinet 12. The suction in the central space of the wheel 11 causes a small air flow in the tube 29 to convey abrasive from the separator to the opening 31 whence it passes to the vanes of the wheel 11. Specification 498,601 is referred to.