Patent GB-569130-A (GB)
Title: Improvements relating to appliances for bending tubes, rods and the like
IPC: B21D7/06
Filed: 1942-10-20
Abstract: 569,130. Angular bending. DRAPER, F. C., and SHAW, J. Oct. 20, 1942, No. 14715. [Class 83 (iv)] Formers.-A fixing bracket for supporting tube or rod bending dies or formers consists of two flat plates at right angles, one for securing it in position and the other formed with a number of holes lying in a circular arc struck about another hole as centre so as to secure thereto by two bolts in various angular positions an arm carrying directly or indirectly the former. The number of standardised parts required in making a series of irregularly spaced bends about different axes, such as in the bending of tubes for hydraulically-operated aircraft turrets, is thus reduced. The bracket comprises an angle plate with the part 19 secured to a horizontal or vertical support and the part 20 provided with three holes 21, 22, 23, at the corners of an equilateral triangle and two series of holes 30 on arcs struck about the holes 22, 23 as centres. An arm 18 carrying the former 31 may thus be secured thereto by bolts 27, 28 in various angular positions. A further hole 30a or a third series on an arc struck about the hole 21 as centre may also be provided. The arm is slotted at 28a where it engages the bolt 28 so that the arm may be swung out of the way if it obstructs the formation of a bend at another point of the work. The bolt 28 is held in position by a finger nut. The arm 18 may be straight, cranked or doublecranked and the former may be secured thereto direct or through an angle piece. The former 31 which is shaped by turning and milling a U-grooved circular blank so as to form a semicircular groove 31d and straight sides 31a, is mounted on a bolt 32 which is angularly adjustable on the arm or angle-piece and secured in position by hardened bushes 40a, 40b on a bolt 39. The bolt 32 is provided with a collar 33 having a number of flutes 37 so that the former may be secured thereon in various angular positions by a pin 36. The upper end 34 of the bolt 32 serves as a pivot for a bending lever which consists of a head 46 welded to a screwed stem 45 and having a pair of holes 47 for counter-clockwise and clockwise bending. Adjustable by a nut 52 on the stem 45 is a housing 48 carrying rollers 49, and between the rollers and the tube is provided a grooved slidable slipper 50 which is guided by pins 51 in the housing engaging grooves in the sides of the slipper. The tube may be held in clamps 9 consisting of bars 11 connected to angle iron base members 10 and provided with a series of holes 12 for a bolt 14 for adjusting the height of the clamping jaw 13. This jaw is kept parallel with the bar 11 by a small roundheaded bolt 16. A stop for the end of the tube may be provided consisting of an adjust. able stud 7 in a bar 5 which is secured by a. bolt to angles 6 so that it may be turned down out of the way when necessary. When making a series of bends in a tube, the tube may be secured in the clamps 9 with its end adjacent the stop and bending effected over a former A. The arm 18 is in this case mounted on a bracket whose other limb is secured back-to-back to a similar limb of a second bracket, the drilled limb of which in this case serves to secure the bracket to a base 3 of moulded synthetic resin. The arm 18 with former B is then brought into position and a second head effected. Further bends are then effected round formers C, D and E, whereupon the other end is bent successively over formers F, G, H. Specification 567,743 is referred to.