GB827823A - Improvements in or relating to seaming mechanisms for securing ends on can bodies - Google Patents

Abstract

827,823. Seaming. METAL BOX CO. Ltd. May 30, 1958, No. 17445/58. Class 83 (4). Seaming mechanism for securing ends on can bodies comprises a non-rotatable chuck 1, a seaming roll support 24 rotatable about the axis of the chuck, at least one rotatable seaming roll 18 supported by one of a pair of arms 22 secured to a spindle 23 journalled in the support for rocking movement about an axis parallel with the axis of rotation of the support, a pair of frusto-conical cam followers 33, 34 spaced apart axially with their bases directed towards each other and supported by the other of said arms for rotation in opposite directions about an axis coaxial with the axis of the seaming roll, and a pair of seaming cams 31, 32 having parallel faces each co-operating with one of said followers to effect movement of the seaming roll towards the chuck to perform a seaming operation and to cause the axis of the seaming roll to move in a path conforming to the peripheral contour of the chuck. The upper end of the chuck stem 2 co-operates with a tubular extension 4 which has a cain 6 engaging rollers 7 carried by a rotatable frame 8 driven by a pinion 12. The cam 6 effects axial movement of the chuck. An ejector rod 13 extending through the chuck is operated by a cam 14 rotatable with the frame 8, said cam engaging rollers 15 carried by an arm 16 slidable in a grooved bracket 17. The seaming roll support 24 is rotated by a pinion 25. The seaming roll 18 is annular and is separated from the spindle 21 by a washer 26 which provides clearance permitting, should the seaming pressure become excessive, lateral movement of the roll which is retained coaxial with the spindle by balls 27 and spring- plates 28. The cam followers 33, 34 are preloaded to eliminate vibration and the cams 31, 32 are each connected to a sleeve 37 axially slidable on the chuck stem 2 and mounted on pillars 38 which carry a control cam 39 cooperating with rollers 40 on the frame 8. As the frame 8 rotates, the control cam 39 causes the cams 31, 32 to be raised or lowered to vary the seaming pressure exerted by the roll 18. In operation, when the chuck has been located in a can end to be seamed to a can body the periphery of the chuck is aligned with the first seaming groove 19 of the roll. Rotation of the frame 8 then causes cams 31, 32 to be lowered to apply the seaming pressure. The support 24 rotates for a predetermined number of revolutions for each rotation of the frame 8 which rotates only once for each can end fully seamed on a can body. Thus, after a predetermined number of revolutions of the support 24, the cam 39 causes cams 31, 32 to be raised so as to disengage the roll from the seam after which the cam 6 lowers the chuck into alignment with the other groove 20 in the roll. Cam 39 then again applies seaming pressure to the roll to effect the second seaming operation after which cam 39 relieves the seaming pressure and cam 6 restores the chuck to its starting position. To displace the can end from the chuck, cam 14 moves the arm 16 to operate the ejector rod 13.