Patent GB-847153-A (GB)
Title: Improvements in or relating to barrelling or tumbling apparatus
IPC: B24B31/02
Filed: 1958-12-17
Abstract: 847,153. Tumbling. ROLLS-ROYCE Ltd. Dec. 17, 1958 [Dec. 24, 1957], No. 40015/57. Class 60. In barrelling or tumbling apparatus the barrel or drum for holding the articles to be treated has a perforated wall and there is provided pump means to deliver liquid and abrasive continuously into the barrel or drum during operation of the apparatus, the liquid and abrasive so delivered flowing from the barrel or drum through the perforations therein. Barrelling apparatus comprises, Fig. 1, a rotating drum 15 consisting of nested cylinders 16, 17 each provided with square perforations 18 and each having an end plate 19 with a central aperture 20. The drum is removably mounted in three-armed spiders 21, 22, the ends of two arms of each spider having projections 23 and the end of the third arm having a pivoted catch 24. The projections 23 and catches 24 engage notches in the outer edges of the end plates 19. The boss of the spider 21 closes the aperture 20 in adjacent end plate 19 and has a stub shaft 25 projecting through the well of a tank 11 and chain driven by an electric motor 29. The boss of spider 22 projects through the tank well and is hollow, being connected by a pipe 31 to the outlet of a pump 13 driven by electric motor 14, the inlet of the pump being connected to the bottom of the tank. The desired quantity of liquid is fed into the tank through an inlet 32 controlled by a float valve. At least part of the required abrasive, which part may be in the form of tablets, is fed into the tank through shoot 36. A liquid outlet 33 contains a filter 34 and cock 35. With the drum 15 removed, the cylinders 16, 17 are rotated relative to one another to obtain an effective size of perforations 18 to pass stone or like chips but to retain articles being treated. The appropriate quantity of chips is then charged into the drum which is replaced and rotated until all the chips have passed into the tank 11. The drum is again removed, charged with articles to be treated, and replaced. A timing control then effects opening of a liquid supply valve to charge the tank with liquid, feeding of abrasive through shoot 36, and starting of the motors 14, 29. The drum rotates for the appropriate treatment time during which liquid, chips and other abrasive are pumped from the tank into the drum and return through the perforations to the tank. The motor 14 is then stopped, rotation of the drum being continued until all the chips have passed to the tank. The motor 29 is then stopped, and valve 35 opened to drain off the liquid from the tank. The drum with the treated articles therein is removed, and the apparatus is ready for treatment of the next batch of articles. To remove the chips, the pump motor 14 is started to transfer the chips into the drum, the perforations having been adjusted so as not to pass the chips. The drum with the chips therein is then removed. In another embodiment, Figs. 2 and 3, a ring 40 secured to the periphery of one end plate 19 has wedge portions 41 engageable behind dogs 44 on the flange 43 of a driving plate 42. The plate 42 has a hollow spigot 45 which carries a driving sprocket 47 and engages a pipe 48 leading from the pump. The other end of the drum has a charging aperture 49 closed by a disc 50 rotatable on a spindle 51 carried by closure member 52, the disc 50 being urged into contact with the end plate 19 by a spring 53. The closure has a window, is hinged at 54 and held closed by a catch 55. In both embodiments, a ring 37 may be welded to cylinder 16 and carry set screws 38a the heads of which are received in arcuate slots 38 in the end plate 19 welded to cylinder 17. The ring 37 may have a scale indicating the effective size of the perforations 18 viewed through a slot in the disc 19.