GB921582A - Tube and bar bending apparatus - Google Patents

Abstract

921,582. Corrugating; angular bending; stretch bending. MACOMBER Inc. Nov. 24, 1961; No. 42159/61. Class 83 (4). Tube and bar bending apparatus comprises means for continuously moving a tube or the like longitudinally therethrough, a pair of dies spaced longitudinally in the path of the moving tube, tube clamping means associated with each of said dies, a third die located between said pair of dies and movable transversely across the path of said tube, each of said pair of dies and said third die being movable toward and from each other longitudinally of the path of the moving tube, and means actuated by the movement of the tube for operating said clamping means and moving said third die perpendicular to the path of the tube to continuously form successive V-shaped bends in the continuously moving tube. Tube 14 moving continuously from a tube mill 13 is clamped at its leading end between a grooved upper die 61 and a grooved circular lower die 62. The die 61 is slid downwardly, in guides 68 in a slide 7 movable horizontally, by toggle levers 69 operated by an hydraulic cylinder 78 so as to clamp the tube against the die 62 which is carried by a block 79 having rollers 82 engaged in cam slots in plates 83 so that, after bending, the die 62 may be moved by hydraulic means downwardly and transversely out of the path of the moving bent tube. The tube 14 is also held between a clamp 18 on a horizontally movable slide 5 and a cooperating clamp 17 moved by toggle levers 33 operated by a piston 40 of an hydraulic cylinder which also operates toggle levers 34 to bring a circular die 26 into tube-engaging position. A circular bending die 49 is then moved down by an hydraulic cylinder 43 on a horizontally movable slide 6 to engage the tube midway between the slides 5 and 7 so as to bend the tube into V-shape. During this operation the tube is under tension, so as to be stretch bent around the die 49, owing to the resistance of movement of the slides 5 and 7 towards the slide 6 due to pneumatic piston and cylinder means 103, 104 connecting the slides 5 and 6 and pneumatic piston and cylinder means 107, 108 connecting the slides 6 and 7. On completion of the bend a switch 200 on the slide 6 is contacted to cause the various dies and clamps to retract and the slides 5, 6, 7 to return to their initial position, the slide 5 being moved by a pneumatic cylinder 100. The tube 14 continues to move to the right until the previously formed bend contacts switches 188, 189 on the slide member 7 whereupon the cylinder 43 is actuated to produce a further bend in the tube. The previously formed bend is engaged by the dies 61, 62, dies 61<SP>1</SP>, 62<SP>1</SP> and 61<SP>11</SP>, 62<SP>11</SP> also slidable by toggle means on the slide 7, the dies 61<SP>11</SP>, 62<SP>11</SP> moving so as further slightly to stretch the bent tube around the die 62<SP>1</SP>. U.S.A. Specification 2,457,250 is referred to.