| 摘要 |
<p>1349541 Abrasive blasting BADISCHE MASCHINENFABRIK GmbH 15 July 1971 [29 July 1970 7 April 1971] 33229/71 Heading B3D An abrasive blasting machine includes a cleaning device 15 for recycled blasting material, means for measuring the degree of soiling of the material in use, and means 21 for returning sufficiently clean material, e.g. to a centrifugal wheel 2 or nozzle means (not shown), while excessively soiled material is returned to the cleaning device 15. Used material from a blasting chamber 1 is transported to the cleaning device 15 by conveyers 6, 13 air suction through a pipe 16 separating impurity particles, e.g. sand, into a conduit 18, while the blasting material enters a conduit 20. Radiation from a source 19 is monitored by a receiver 25 connected to an evaluator 37 controlling a drive 26 of a flap 21. When the receiver indicates excessive soiling, the flap 21 directs the material into a hopper 23, the material falling directly on to the conveyer 6 for return to the cleaning device 15, while if sufficiently clean, the material is directed into a container 27 for feeding to the wheel 2. A second measuring means 9, which may be used alone for controlling contamination by magnetic material, comprises non-magnetic conduits (31), (33), Fig. 2 (not shown), surrounded by induction coils (32), (34), hot air being supplied to a housing (39) containing the conduits (31), (33) by a fan (41) and heater (42). One conduit (33) is packed with a control material, e.g. pure blastant, while discharged material from the conveyer 6 passes through the other, a control device 12 governing the speed of the conveyer 6 in accordance with the differential outputs of respective lines (46), (47) from the coils (32), (34). With excessive soiling, the conveyer speed is reduced, to reduce the load on the cleaning device 15, a throttle element 57 also being actuated to control the rate at which the blasting material is supplied to the wheel 2. New material may be supplied from a container 54 by a regulating device 55.</p> |
