Patent GB-999080-A (GB)
Title: Improvements in or relating to barrel finishing machines
IPC: B24B31/03
Filed: 1963-07-17
Abstract: 999,080. Barrel finishing. ALMCO SUPERSHEEN DIVISION OF GREAT BRITAIN Ltd., and C. J. A. KELLARD. July 9, 1964 [July 17, 1963], No. 28341/63. Heading B3D. A barrel-finishing machine comprises a tumbling barrel rotatably supported with its longitudinal axis extending substantially horizontally and having a peripheral wall extending between end plates, means for rotating the barrel in either direction about the said axis, an opening in one end plate for feeding parts and media into the barrel, an aperture in the other end plate and duct means for feeding the contents of the barrel from said aperture on to a discharge surface carried by the said other end plate, the relative disposition of said aperture, said duct means and said discharge surface being such that when the barrel is rotated in one direction the contents thereof are retained in the barrel and when the barrel is rotated in the other direction the contents are fed from the aperture and through the duct means on to the discharge surface. An octagonal barrel 1 comprises panels 2 secured between circular end plates 3, 4 having flanges for engagement with drive rollers; the panels are so tapered that the crosssectional area of the barrel increases progressively from plate 3 to plate 4. The plate 3 has a central aperture 5 through which workpieces and finishing media are fed into the barrel. Secured to the plate 4 is a frustoconical member 7 with a flange 8. An opening 9 in the plate 4 adjacent its periphery communicates with a duct 10 supported on the plate and leading to an opening 11 in the member 7. The shape and disposition of the duct 10 with respect to the openings 9, 11 is such that when the barrel is rotated anti-clockwise. Fig. 2, any workpieces and media entering the duct through the opening 9 fall back into the barrel, whereas when the barrel is rotated clockwise, workpieces and media flow through the duct to be discharged through the opening 11. In operation, workpieces and media, together with liquid and/or compound if required, are loaded into the barrel through the feed opening 5. The barrel is rotated anti-clockwise to finish the workpieces and at the end of the finishing period the rotation of the barrel is reversed to discharge the contents of the barrel. Two ducts 10 and associated openings 9, 11 may be provided angularly displaced 180 degrees with respect to each other. A degreasing unit 12, a deburring unit 13, and a burnishing unit 14 are arranged in tandem, each unit having a barrel 1 as described above driven by rollers 15 driven from an electric motor 16 to give a barrel speed for finishing, e.g. 24 r.p.m. and a slower reverse barrel speed for discharging, e.g. 12 r.p.m. In the unit 12, the flange 8 of the member 7 has secured thereto for rotation with the barrel a separator 19 comprising an openended cylinder having an internal helical flight 20 and a perforated peripheral wall formed of wire mesh comprising a first portion 19a of fine mesh through which only solution can pass and a second portion 19b of larger mesh which passes the media but not the workpieces. Solution passing through the portion 19a is collected in a cowling 21 and thence flows to a collecting tank 23. It is fed through a clarifier to a tank 29 containing an immersion heater 30 and is then fed by a pump 28 and pipe 26 to the barrel. Media passing through the portion 19b falls into a shoot 24. Water for rinsing the workpieces and media is pumped by a pump 32 from a tank 31 at the discharge end of the unit to a pipe 33 extending into the separator 19 and having spraying nozzles. The water drains into the shoot 24 and returns to the tank 31. In the units 13, 14 the rinsing arrangement is omitted, and the separator of unit 14 discharges the workpieces into a combination washerdrier in which they are finally rinsed and then dried. Also in the units 13, 14 the two tanks 23, 27 of the unit 12 are replaced by a single tank 23a. Workpieces are loaded into the feed shoot 25 of the unit 12 by any suitable means such as a skip-hoist. Media is supplied to the feed shoot from a hopper 36. Media collected in the shoot 24 may be fed to the hopper 36 by a pneumatic tube and a pneumatically-operated gate valve controlling the supply of media from the hopper to the barrel. The motors 16 and pumps 28, 32 may be controlled by time switches and/or limit switches.