Patent GB-156633-A (GB)
Title: Flange bending machine
IPC: B21D19/04
Filed: 1921-01-06
Abstract: 156,633. Palmer, R. K., and Milne, W. G. June 7, 1918, [Convention date]. Angular bending.-A machine for bending the flanges of channel bars particularly for ships' ribs, comprises a pair of rolls for each flange, which are bodily adjustable to different angular positions to bend the flanges to different angles along their length according to the location of the bar in the ship's frame. The two flanges may thus be bent simultaneously either outwardly or inwardly in a single passage of the bar through the machine. A pair of bevelled rolls 41, 42 are mounted in each of a pair of rings 26, angularly adjustable in fixed heads 25, which are secured by bolts through elongated slots to a base 29 secured to a wheeled frame 20 and which are relatively adjusted along the base by screws 31 according to the width of the bar. The rolls are mounted so that the point of bend is in the centre of the ring. The wheeled frame moves along a track between a furnace or a series of furnaces and a bed on which the bars are afterwards bent to the required longitudinal curvature, a small platform being placed in front of the furnace to facilitate handling of the bars. The frame has an operator's platform 64 and also a raised platform 64<a> at the same elevation as the furnace floor, small platform, and bending bed to serve as a furnace-charging platform, or, where there are a series of furnaces, to serve as a platform for supplying the bars to one furnace while flange bending is effected on bars drawn from a second furnace. This raised platform also serves for the operator and other operatives to pass from one side of the machine to the other and also as a shelf for the operator's mask, goggles, gloves, etc. Each ring 26 is retained in its head by plates 27 and is angularly adjustable by a toothed quadrant 28 engaged by a pinion 28<a>, Fig. 4, mounted on a shaft in the head, the other end of which carries a worm wheel 28<c> engaging a worm 28<d> on an inclined shaft 28<e> which is operated either by hand or by a reversible compressed-air motor 78 through gearing 79. Air is supplied through a pipe 82 to the motors 78, either independently through valves 80 or simultaneously through the valve 81. The rolls are mounted in brackets 45, Fig. 12, secured to the rings 26 by bolts passing through enlarged holes and each capable of slight angular adjustment by a hand-operated eccentric 49 to suit flanges of different sections. The rolls are held in set position by eye bolts 50, Fig. 1, pivoted to the brackets and secured by nuts to lugs on the rings. The roll shafts are also axially adjustable through threaded split locking rings 51, 52. The rolls are driven so as to feed as well as bend the bars by worm wheels 43<a> engaging worms 44, Fig. 4, in the brackets 45<1>, the shafts of which carry sprocket wheels 46, which are driven by separate chains from a shaft 59 rotated by a belt from a motor 62, preferably electric. The sprocket wheels are arranged so that the distance round them is substantially constant for any position of the wheels. In the case of the rolls for bending the flange furthest away from the shaft 59, an idle sprocket 63, Fig. 4, is provided in addition for this purpose and so as to prevent the chain from fouling the bar. For heavy bars, the feed may be assisted by hand or by furnishing the furnace with devices for pushing or pulling the bar or jarring or loosening it from the furnace floor. The bar is supported in each head by a roll 33 on a fixed shaft 34 secured by clamps to a projection 35 from the fixed head having a screw 38<1> for vertical adjustment. For bending the flange outwardly as shown in Fig. 1, the bar is held on the roll 33 to prevent bending of the web by a bevelled roll 53 on a bar 54 adjustable by a screw 56 in a housing 55 extending from the head. This roll is supported by a friction roll 57. A similar roll is also mounted on the rear head, for use when bending flanges outwardly. When bending inwardly, as in the present case, to the shaft 34 mounted in the rear head is adjustably secured a roll mounted on a vertical axis which bears against the outside of the other flange to take the thrust. A similar roll may be carried on the shaft 34 shown in Fig. 1. The angular position of the rings is indicated by pointers 65 moving over seales on the peripheries of the heads. The distance in feet which the bar has travelled at any moment is indicated by a dial 67, Figs. 1 and 17, which is mounted on one of the heads and has two pointers, one for each head, the pointer for one head being jointed so that it can be set back or ahead to represent the position of the bar in that head. The pointers are connected by chain gear 77 to a shaft 75<1> carrying a pinion 73, Fig. 14, meshing with a pinion 72 on the shaft of a wheel 68 in frictional engagement with the roll 33. The shaft 75<1> is mounted at one end in a support 75 and at the' other end in a slide 74 pressed by a spring 71 along a guide 69 secured to the projection 35. In order that the angular adjustment of the rolls may be made by the operator at the required times without mental effort, a chart may be clipped over each scale on the heads, graduated at the centre similarly to the scales and provided with lines, Fig. 17, separated by dots at which the number of feet of traverse are marked. The lines s, t, u, v, and f, x represent distances traversed with rolls in fixed angular positions, and the series of lines t, v and u, x represent distances traversed at other angular positions. The position of the rolls may thus be adjusted by observing the dial and the charts. The adjustment should be made gradually so that the pointers moving over the charts are brought to the required positions in synchronism with the pointers on the dial. To compensate for the tendency of the flange to straighten when the bar is subsequently bent, the bend in'the flange may be slightly increased beyond the required angle. The wheeled frame is propelled by spur gear from one of the wheel axles through a shaft 84 driven by chain gear from the shaft 59 through a clutch controlled by a hand lever 90. The motor may be reversible under control of a hand controller 91 or may be connected by a double friction clutch and gearing.