GB171560A - Improvements in means for bending tubes and the like - Google Patents

Abstract

171,560. Goodyear, H. J., Inns, W. J., Jackson, G., ritter, C. H., and Poulton, J. Sept. 21,1920. Angular bending; formers; mandrels.-In an apparatus for bending tubes or metal mouldings &c. of the type in which a sweep-arm with a flatfaced bearer is moved round a fixed former or a former rotated in contact with a fixed external support and in which an internal mandrel with a flexible nose-piece is used which is drawn relatively through the tube, the convex surface of the flexible nose-piece is arranged so that it supports the tube directly at the point of bend. For bending at two points, a pair of grooved formers 2, Fig. 1, secured together at the requisite distances apart by interchangeable plates 5, 6 are clamped by bolts 3 to the bed-plate 1. Mounted on the bolts are levers 16 and bottom plates, between which are secured by removable pins 15 grooved flat bending-blocks 12, the side flanges of which overlap the edges of the formers. The blocks are clamped to arms 14, which are connected to the levers 16 by stays 19 and which have lugs 20 at their outer ends for carrying the rods 21 of internal mandrels 22, Fig. 9, connected by links 23 to nose-pieces 24. In order to insert the tube 8 to be bent, the pins 15 are removed and the arms 14 swung round the bolts 14'. The tube is then secured by a grooved block 9 through a U- shaped clamp 10, and the arms then replaced, the ends of the tube resting against hinged stops 26. The mandrels are then inserted. Bending is then performed by swinging the lever 16 round the bolt 3, stops being provided for limiting the amount of the bend. The mandrel may then be removed by drawing through the tube and lugs 20. In a modification, the tube is pushed by a projection 29, Fig. 11, on a hand tool 28 over a fixed internal mandrel 22, through a fixed externally grooved block 12 provided with U-shaped guide strips 27 until it abuts against a pivoted stop carried by the block 12. It is then secured by a clamp 10 to a grooved former 2 which is rotated by a handle 16 to bend the tube. After bending, the tube is removed from the former h<y> a plunger 30, Fig. 16, operated by a lever 31. The tube is of D-section and the internal mandrel consists of a pair of D-shaped blocks 22, 24, Fig. 14, connected by links 23 and carried by a pair of rods 21.