Patent GB-614915-A (GB)
Title: Improvements in or relating to machine for bending and shaping rolled irons and the like
IPC: B21D7/08
Filed: 1945-05-22
Abstract: 614,915. Angular bending. BUGATTI, E. May 22, 1945, No. 12788. Convention date, May 31, 1944. [Class 83 (iv)] In a machine for bending and altering the flange angle of rolled sections such as angles, tees, &c., a bending and shaping head is mounted in parallel relation to a surface table for lateral and longitudinal movement across the table. The head has three conical rollers, one of which bears on the flange lying on the table and the remaining two grip either side of the upstanding flange of the work. A series of pegs outline the shape to which the work is to be bent and the head is displaced accordingly to strain the work against the pegs ; at the same time shaping the vertical flange to the required contour. The head is slidably mounted on two beams 21, 22, Fig. 3, supported at their ends in bosses 23, 24 of posts 19, 20, which are adapted to move longitudinally of the bed on rollers 17, 18. A shell 27 and side cheeks 31 provide a slide for a sector 32 carrying rollers 7 and 8, and a trunnion 28 integral with the shell is mounted for pivotal movement about a vertical axis in a sleeve 29 of support 26. A nut 52 having tommy holes 53 adjusts the pressure of a washer 47, fitted between a shoulder 48 on trunnion 28 and a sleeve 49 riveted at 50 to a reduced diameter 51 of the trunnion, to urge the shell against the surface of the bed, thereby increasing the pressure on roller 12 which is supported on a bearing 62 fast with a bracket 60 secured to the shell. A conical roller 66 is mounted in a housing in bracket 60 on an eccentric spindle 68 which is held by a bolt 70 having a cylindrical tip to engage a groove 69 in the spindle. Holes 71 are provided in the head of the spindle to rotate it and impart further pressure adjustments to roller 12 through roller 66 ; the spindle being afterwards held against rotation by a ball 74 and screw 73. In operation pegs 3 are fitted into the holes in the bed to define the curvature of the work ; the pegs having eccentric heads so that slight rotation can give accurate form to the curve. A bolt 85 passes through the pegs to lock them by drawing a cone 87 into the split lower shank of the peg. Clamping dogs 84 hold the horizontal flange of the work 13 at points near the pegs. Angular adjustment of rollers 7 and 8 is transmitted by a bar 101 engaging tommy holes in the head of a spindle 94 which carries a pinion 93 in a bore of the shell 27 to mesh with a toothed sector integral with sector 32 carrying the rollers. A manually operable lever 88 is splined at 89 to engage the top 90 of the trunnion. 28 and controls swinging movement of the head to enable the rollers to lie in a plane normal to the curve of the work. The head may be tensioned laterally by a winch having a cable 80 attached to a fork 81 which carries a roller 82 to engage a stirrup 83 which girdles the head and is adapted to swing about a pin 79 to allow the free movement of sector 32 necessary for shaping the work. The carriage and head are moved longitudinally by roller chains secured to the bottom of posts 19, 20 and running on wheels supported in brackets at each corner of the bed. The chains may be driven by an electric motor or other means and may incorporate a gearing system in the drive. In a modification using fluid pressure to operate the lateral movement of the head on beams 21, 22, a tank 124, Fig. 7, communicates with the atmosphere through plug 125 and is connected to the suction side of pump 126 which forces liquid into a chamber 112 of a cylinder 109 which may be attached to the post 20. The piston 110 has a rod 114 connected to the head support 26 and therefore holds the rollers against the work, keeping them in close contact with the path defined. by pegs 3. As the loci of the work changes direction the rollers transmit pressure through support 26 to move piston 110 against the fluid pressure in chamber 112 and when the pressure in this chamber exceeds a predetermined limit a valve 127 opens, allowing the fluid circulated by pump 126 to flow back into tank 124. When the pressure falls by reason of a change in the loci to the opposite direction the spring valve 127 shuts and pump 126 again operates to ensure the close contact of the work through support 26 and the rollers, with the path of the pegs.