EP3888813B1 - Bending device for producing a continous lattice - Google Patents

Description

The invention relates to a bending device for a plant for the continuous production of a lattice girder, in which a diagonal belt wire running back and forth in a zigzag shape in the lattice girder can be produced in one production direction, with three bending mandrels arranged transversely to the production direction, of which two bending mandrels are at a variable distance from one another and constantly open are at the level of the supplied diagonal belt wire and the third bending mandrel is located between the other two bending mandrels and can be moved up and down from a starting position along the diagonal wire and actively causes bending with an adjustable upper reversal height.

In known bending devices, such as from AT283868 , GB 2 346 575 A , DE 2063041 , U.S. 3,487,861 and FR 71.44549 , diagonal wires can be generated with only isosceles triangles. Other teachings, such as the EP 2 789 406 A1 and WO-A-2013 000551 , which forms the basis for the preamble of claim 1, are very expensive in terms of apparatus.

The disadvantages are serious, since the customer often only orders a limited number of each type of girder, be it of different heights or widths of lattice girders or those with different thickness chords or with different zigzag shapes of the diagonal chords. The time-consuming conversion of the welding and bending machine makes orders considerably more expensive.

The object of the invention is to provide a bending device for all types of lattice girders without time-consuming conversion of the welding and bending machine. Likewise, a system that makes this possible should also be provided.

In a bending device of the type mentioned at the outset, the invention consists in that, for the purpose of bending the individual prongs of the diagonal belt wire, the bending mandrel, which can be moved up and down, is moved along an approximately circular path that lies in a vertical plane running through the respective diagonal wire, and additionally along the radius of the circular path is movable, so that the prongs of the diagonal belts can be designed either with the same limbs or with limbs of different lengths and angles, which is caused by the bending mandrel, which can be moved up and down, being attached to one end of a swivel arm and a roller to the other end attacks, the shaft of which is mounted at both ends at the end of a first of two parallel links, the other end of one link being fixed laterally to a first gear wheel that can be driven in rotation, whose shaft that can be driven in rotation remains on the same axis as the second at the level of the supplied diagonal wire ends, is a fixed bending mandrel, whereby the two links together with the roller and the swivel arm which rests on it and carries the bending mandrel that can be moved up and down can be pivoted by turning the gear wheel, and whereby by turning a further rotationally drivable shaft, which is also coaxial with the second, stationary bending mandrel that remains permanently at the level of the supplied diagonal wire, the two links together with the shaft and a second gear wheel, which meshes with the first, driven gear wheel and is mounted at the end of the shaft, which is also the rear end of the first of the two parallel links carries, are pivotable, whereby the effective length of the pivot arm acting on the bending mandrel that can be moved up and down is adjustable, so that the movable bending mandrel can be moved along an approximately circular path in a manner through the respective Diagonal wire running vertical plane is, and is also movable along the radius of the circular path.

An embodiment of the bending device is characterized in that the second bending mandrel remaining at the level of the supplied diagonal wire is stationary and the first bending mandrel can be clamped to the moving diagonal wire and can be run along with it to the desired bending point.

The bending device can also be part of a system for the continuous production of a lattice girder, the lattice girder being welded together from two lower chord wires and one upper chord wire, and from one diagonal chord wire running back and forth in a zigzag shape between the upper chord and each of the two lower chords and the lower chords and the upper chord in the cross section of the lattice girder lie at the corners of a triangle, at the apex of which is the upper chord, in which system all five chord wires can be fed from a plurality of wire threading and wire changing devices to a feed device and from there parallel in the production direction to a welding and bending machine , In which first for the bending of the two diagonal belt wires a bending device is provided, and wherein the feed device for the upper belt wire is adjustable in height, so that the diagonal belts optionally with different heights teeth for producing a Lattice girders can be shaped at different heights, and the welding and bending machine has welding devices for welding the upper chord wire to the upper angled portions of the teeth of the diagonal chord wires and for welding the lower chord wires to the lower angled portions of the teeth of the diagonal chord wires and a gripping and transport device acting on the upper chord , characterized by a present for each of the belt wires, available plurality of wire threading and wire changing devices for wires of the same or different thickness, quality and/or surface, which wire threading and wire changing devices can each be brought in the direction of the wire in the feed device and can be reversed in their running direction, as well as one for each of the belt wires on the input side existing scissors, which can be operated independently or together with the other scissors, the scissors for the upper belt wire being height-adjustable together with its feed device.

The invention is explained in more detail using an exemplary embodiment of a plant for the continuous production of a lattice girder, which is shown in the drawing. In the drawing shows 1 the system as a whole schematically in a side view, 2 the same system in plan view or show the Figures 3-5 the principle of the bending mechanism of the system for the diagonal chord wires of the lattice girder in perspective, top view or side view, 6 a perspective view of the bending mechanism, but different from that in FIG 3 seen from the opposite side and the Figures 7, 7A an exit ( 7 ) or final position ( Figure 7A ) of the bending mechanism when bending an unequal-sided prong of the diagonal belt wire, the Figures 8, 8A an exit ( 8 ) or final position ( Figure 8A ) of the bending mechanism when bending an isosceles point of the diagonal belt wire.

In the Figures 1 and 2 Wire threading and changing devices for each of the five chord wires of the lattice girder are denoted by 4, namely for two lower chord wires 1, 1', one upper chord wire 2 and two diagonal chord wires 3, 3', each of which is located on the finished girder between the upper chord 2 and one of the the two bottom flanges 1, 1' runs back and forth in a zigzag shape. The belt wires 1, 1', 2, 3, 3' and the belts made from them of the lattice girder have the same designation. As indicated in the drawing, for each of the belt wires 1, 1', 2, 3, 3' there are a number of wire threading and changing devices 4 with wires that can each have the same or different thicknesses, qualities and/or surfaces . The wire threading and changing devices 4 can each be brought in the direction of the line of the wire located in subsequent feed devices 6 and can be reversed in their running direction. A pair of scissors arranged on the input side in front of or on the respective feed device 6 is denoted by 5 and can be actuated independently or together with the other scissors 5 . The belt wires 1, 1', 2, 3, 3' can each be threaded in together or individually and cut. The scissors 5 for the upper chord wire 2 is located in the middle of a feed device 6 intended for this purpose, which is height-adjusted together with the scissors 5 in the event that the height of the lattice girder is to be changed. The scissors 5 for the diagonal chord wires 3, 3' and for the lower chord wires 1, 1' are arranged in front of the respective feed devices 6'. A bending device 8 for bending the diagonal belt wires 3, 3' into a zigzag shape follows in the direction of production indicated by an arrow 7. The bending device 8 has three bending mandrels 9-11, of which two bending mandrels 9, 10 are always at a distance from one another at the level of the supplied diagonal belt wire 3 or 3' and the third bending mandrel 11 from a starting position between the other two bending mandrels 9, 10 and can be moved up and down along the diagonal wire 3 or 3'. The upper reversal point of the bending mandrel 11, which can be moved up and down, can be adjusted in height in the event that the height of the lattice girder has to be adjusted. The zigzag shape of the diagonal belt wires 3, 3' has upper 12 and lower bends 13 on. The bending device 8 is below based on the Figures 3-6 described in more detail.

The bending device 8 is followed by a welding device 14 for welding the upper flange wire 2 to the upper bends 12 of the diagonal flange wires 3, 3', as well as a gripping and transport device 15 acting on the upper flange 2. This is followed by a welding device 16 for welding the lower bends 13 of the diagonal flange wires 3, 3' with the lower belt wires 1, 1'. This completes the lattice girder.

In addition, there can be scissors 17 on the outlet side for cutting the lattice girders to length in the case of large-scale production.

So that the production of lattice girders of different widths is also possible without tedious conversion work, there is also a spreading or narrowing device 18 at the end of the device, which acts on the bottom flanges 1, 1'.

By means of the device described, lattice girders of all kinds can be produced without time-consuming conversion of the welding and bending machine. The wires to be exchanged are cut off by means of the scissors 5 on the input side, returned to their respective wire threading and changing device 4 by the shortest possible route and then replaced by the new wire threading and changing device 4 already available with the appropriate wire, in which the wire then only needs to be must be advanced to the respective feed device 6.

the Figures 3-6 show the principle of the bending device 8, which can be used independently of the inlet section of the system described, but preferably subsequent to it.

The bending mandrel 11, which actively brings about the bending by its upward movement out of the direction of feed of the diagonal wire 3 or 3', is constantly between the two along the direction of feed of the diagonal wire arranged bending mandrels 9, 10 are arranged at one end of a swivel arm 20. Of the other two bending mandrels 9, 10, which are always in the feeding direction of the diagonal belt wire 3 or 3', the second one 10 in the production direction 7 is fixed and the first bending mandrel 9 clamps on the moving diagonal wire 3 or 3' and runs with this to the desired bending point with, in particular, the Figures 7, 7A, 8 and 8A demonstrate. The reversal height of the third bending mandrel 11, which can be moved up and down, is adjustable, as has already been mentioned above. A roller 23 acts on the end of the swivel arm 20 opposite the movable bending mandrel 11, the shaft 24 of which is fixed at both ends to one end of one of two parallel links 25 and 25'. The other end of a first 25 of the two links 25, 25' is fixed to a rotatably drivable shaft 27 and to the side of a first gear wheel 26 driven by the shaft 27. The shaft 27 has the same axis as the axis of the second, fixed bending mandrel 10. By turning the gear wheel 26, the links 25, 25' together with the roller 23 and the pivot arm 20 bearing the movable bending mandrel 11 and bearing against it can be pivoted. By rotating another rotatably drivable shaft 27', which is also on the same axis as the second fixed bending mandrel 10, which always remains at the height level of the supplied diagonal wire 3 or 3', the two links 25, 25' together with the shaft 24 and a second gear wheel 28 meshing with the first driven gear 26 and journalled on the end of the shaft 24 which also carries the rear end of the first 25 of the two parallel links 25, 25'. Thus, the effective length of the swivel arm 20 on the movable bending mandrel 11 can be adjusted, as indicated by the arrow 21, and the desired ellipse-like path of the movable bending mandrel 11 is obtained Production direction is in the Figures 4, 5 drawn reversely as in 3 .

With such a bending device 8, optional bending beams with isosceles teeth of the diagonal chords, as shown in 3 left and in figure 5 are shown on the right, or bending beams with differently long and inclined legs 31, 32 of the prongs of the diagonal belts 3, 3 'can be produced, as shown in 3 right and in figure 5 are shown on the left. The legs 31, 32, which are inclined at different angles, are connected by sections 33 running in the beam direction between the prongs of the diagonal chords 3, 3', which are welded to the lower chords 1, 1'.

The different phases of bending are in the Figures 7, 7A, 8 and 8A illustrated, where the clamping device connected to the first bending mandrel 9 in the production direction is also shown schematically.

Claims (3)

1. A bending device for a system for the continuous production of a lattice, in which a diagonal chord wire (3 or 3') running to and fro in a zigzag shape in the lattice can be produced in a production direction, having three bending mandrels (9-11) arranged transversely to the production direction, two of which bending mandrels (9, 10) being located at a variable distance from one another and constantly at the height level of the supplied diagonal chord wire (3 or 3 '), and the third bending mandrel (11) being located between the two other bending mandrels (9, 10) and being movable up and down from an initial position along the diagonal wire (3 or 3') and actively effecting the bending with an upper return height which can be set, characterised in that, for the purpose of bending the individual points of the diagonal chord wire (3 or 3'), the bending mandrel (11) which can be moved up and down is movable along an approximately circular path, which lies in a vertical plane running through the respective diagonal wire (3 or 3'), and additionally along the radius of the circular path, so that the points of the diagonal chords (3, 3') can be formed either with identical sides or with sides (31, 32) having different lengths and inclinations, which is effected in that the bending mandrel (11) which can be moved up and down is fastened to one end of a pivot arm (20), on the other end of which a roller (23) acts, the shaft (24) of which is mounted at both ends on the end of a first (25) of two parallel control arms (25, 25') in each case, wherein the other end of the one control arm (25) is fixed laterally on a rotationally drivable first gearwheel (26), the rotationally drivable shaft (27) of which is coaxial with the second, stationary bending mandrel (10) which remains constantly at the height level of the supplied diagonal wire (3 or 3'), wherein the two control arms (25, 25'), together with the roller (23) and the pivot arm (20) abutting thereon and supporting the bending mandrel (11) which can be moved up and down, are pivotable by means of the rotation of the gearwheel (26), and wherein, by rotating a further rotationally drivable shaft (27'), which is likewise coaxial with the second, stationary bending mandrel (10) which remains constantly at the height level of the supplied diagonal wire (3 or 3'), the two control arms (25, 25'), together with the shaft (24) and a second gearwheel (28), which meshes with the first, driven gearwheel (26) and is mounted at the end of the shaft (24), which also supports the rear end of the first (25) of the two parallel control arms (25, 25'), are pivotable, as a result of which the effective length of the pivot arm (20) acting on the bending mandrel (11) which can be moved up and down is adjustable, so that the movable bending mandrel (11) is movable along an approximately circular path, which lies in a vertical plane running through the respective diagonal wire (3, 3'), and additionally along the radius of the circular path.
2. The bending device according to Claim 1, characterised in that the econd bending mandrel (10) remaining at the height level of the supplied diagonal wire (3 or 3') is stationary, and the first bending mandrel (9) can be clamped on the moving diagonal wire (3 or 3') and can move together with the latter as far as the desired bending location.
3. A system for the continuous production of a lattice, wherein the lattice is welded together from two lower chord wires (1, 1') and an upper chord wire (2) and from a diagonal chord wire (3 or 3') running to and fro in a zigzag shape between the upper chord (2) and each of the two lower chords (1), and the lower chords (1, 1') and the upper chord (2) lie at the corners of a triangle in the cross-section of the lattice, at the apex of which triangle the upper chord (2) is located, in which system all five chord wires (1, 1', 2, 3, 3') can be supplied from a plurality of wire threading and wire changing devices (4) to a feed device (6, 6', 6") and from there in parallel in a production direction (7) to a welding and bending machine, in which a bending device (8) for bending the two diagonal chord wires (3, 3') is provided first, and wherein the feed device for the upper chord wire (2) is height-adjustable (6), so that the diagonal chords (3, 3') can optionally be formed with points of different heights to produce a lattice with different heights, and wherein the welding and bending machine has welding devices (14 or 16) for welding the upper chord wire (2) to the upper angled portions (12) of the points of the diagonal chord wires (3, 3') and for welding the lower chord wires (1, 1') to the lower angled portions (13) of the points of the diagonal chord wires (3, 3'), and a gripping and transporting device (15) which acts on the upper chord (2), characterised by an available plurality of wire threading and wire changing devices (4) present for each of the chord wires (1, 1', 2, 3, 3'), for wires of the same or different thickness, quality and/or surface, which wire threading and wire changing devices (4) can each be brought towards the wire located in the feed device (6) and reversed in their travelling direction, and shears (5) which are present on one side for each of the chord wires (1, 1', 2, 3, 3') and can be operated independently or jointly with the other shears (5), wherein the shears (5) for the upper chord wire (2) are height-adjustable together with the feed device (6) thereof, wherein the bending device (8) is designed according to Claim 1 or 2.

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