GB565184A - Improvements in and relating to tools for bending tubes and rods - Google Patents

Abstract

565,184. Angular bending. COWLIN & SON, Ltd., W., and HURLEY, R. E. March 8, 1943, No. 3759. [Class 83 (iv)] In an apparatus for bending tubes and rods of the kind having at least two co-operating parts with complementary shaping surfaces movable towards one another, a bending member pivoted on one of the co-operating parts is rocked on its pivot by means on the other co-operating part in timed relation with the movement of the movable part so as to cause it to perform a bending operation on the tube or rod additional to that effected by the co-operating parts. A tool of box construction to be placed on the bed of a press has a fixed tool 1 cooperating with a spring-returned tool 2 movable on guides thereon. On the part 1 is pivoted at 16 a lever 15, one limb of which is grooved to receive the tube &c. 17 and the other limb 151 of which is engaged by an element 18 on the part 2 so as to bend the tube against the side 51, 5<11> of the part 2 after it has first been bent between the edges 5, 4 of the parts 2, 1. The lever 15, which may be spring-returned, is not moved until the element engages the surface 151 at a point towards its pivot, so that the initial motion is rapid but diminishes as the element travels down the surface 15<1>. The other side of the tool may have shaping surfaces for bending the tube in a plane at right angles to the first bends. In another form, the stationary part 1 is provided with a shaping surface 31 and with the element 28 which operates a bending lever 25 pivoted at 26 to the spring-returned movable part 2 and bends one limb of the U-shaped tube 27 over the surface 30 on the upper part 2 after the surface 29 thereon has bent upwards the other limb of the tube by co-operation with the surface 31. The rate of rocking of the lever 25 is varied to adapt its motion to that of the part 2. The lever 25 is returned to initial position by a spring or by a cable or chain on maximum separation of parts 2, 1. The tool may' be provided on the other side with dies for bending the tube to U -shape. The limbs of the U are slightly twisted out of a common plane. Antifriction rolls may be provided at the ends of the element 28 and lever 25. In a further form, Fig. 6, a lever 35 provided with a channelled fibre block may be pivoted at 36 on the part 1 of the tool and operated by an element 38 on the movable part 2 so as to bend the tube against the side of the die block 32 carried by the part 2 after the latter has first forced the tube down into contact with the block on the lever 35. In another form, the movable part 2 has pivoted thereon at 46 a lever 45 provided with rollers 43 which run on a pair of spaced inclined straight or curved guides 48 surfaced with metal or other wear-resisting material to bend the tube round a former 50. The lever is restored to position by a spring 42. The wearing surfaces of the tool may be of compressed fibre whilst the bending lever and its operating element may be of metal, plastics or wood.