Die for a bending or folding apparatus, and a bending or folding apparatus

Abstract

The invention relates to a die (1) for a bending or folding apparatus, comprising: a main body (2); at least one pair of bending aprons (3) which are mounted in the main body (2) so as to be able to pivot passively about axes (B) symmetrically with respect to a central plane (M), and which form a flat bearing surface (4) in the neutral position and a V-shaped swage in the main body (2) in the folded position; at least one restoring component (5) for each bending apron (3) which acts on the bending apron (3) to move it towards the neutral position; at least one sliding component (6) for each bending apron (3), wherein two sliding components (6) in each case rest against the bending aprons (3) in the neutral position symmetrically with respect to the central plane and form, with flat bearing sections, a flat bearing surface for a workpiece (W), and which can slide on the bearing surface of the bending apron (3) transversely to the axis together with a workpiece to be machined. One support section (9) is arranged fixed to the sliding component (6), rests in a neutral position of the bending apron (3) and of the sliding component (6) against a stationary support point (11) on the main body (2) and in the folded position is free of force and lifted off the support point (11).

Description

[0001] DIE FOR A BENDING OR BENDING DEVICE AND A BENDING OR BENDING DEVICE

[0002] The invention relates to a die for a bending or folding device, as well as a bending or folding device with such a die.

[0003] When bending sheet metal in lower tools with adjustable die elements, especially around a bending beam that rotates parallel to the center plane of the die, as described in JP H03 14010 U, the force applied from the tools to the workpiece is already distributed over a single surface. In contrast to bending in V-shaped dies, this has already achieved a significant improvement; however, due to the process, there is still a relative movement between the workpiece and the support surface of the rotating bending beams or rotating jaws. This leads to small scratches on the produced bent parts.

[0004] In order to reduce the scratch marks on the bent part caused by the relative movement between the workpiece and the bending beam during the forming process, it was proposed that a sliding element, for example made of spring steel, be inserted between the workpiece and the bending beam. In this case, relative movement only occurs between the bending beam and the sliding element. Between the workpiece and the sliding part, however, there is no relative movement, and thus no or only a few scratches can occur. An example of such a device is disclosed in EP 3127626 B1. The return of the sliding elements is achieved by spring elements orAn elastic design of a portion of the sliding elements is achieved, which exerts a preload force to move the sliding elements parallel to the support surface on the bending beams in a mutual separation direction, but still allow them to move in a mutual approach direction towards the pivoting element against the preload force along with the stretching of the workpiece during the bending process. The movable plates are secured to the pivoting elements by locking elements, with heads of the locking elements positioned outside the movable plates and serving as stop means to limit the pivoting elements in their initial position under the preload force. A similar construction is also disclosed in US 2017259316 A1.If the spring elements were omitted or broken, the sliding element would be able to move without force, but would have to be moved back to its original position manually or by an additional device after each bending process.

[0005] Finally, DE 19840563 CI discloses a device for die bending, free bending, or stamping bending, comprising a die having a notch and a punch for pressing a workpiece to be bent, which lies above the notch. The device comprises intermediate plates that span the notch edges, act as a shield against the workpiece, and are each pivotable about axes running parallel to the notch edges. The intermediate plates keep the workpiece away from the notch edges, thereby preventing damage to the workpiece caused by the notch edges or mutual entanglement and distortion of the deformation. These intermediate plates are pivotable or can be displaced in the form of sliding elements without pivoting and without force, in the sense that they can at least partially and substantially follow the movement and deformation of the workpiece during bending.

[0006] The object of the present invention was to develop a device that enables the effective and material-friendly machining of workpieces with increased functional reliability and a simple design. To ensure a sufficient range of motion for the sliding elements, a further objective of the invention is to provide an advantageous design.

[0007] This object is achieved by a device according to the claims.

[0008] The device according to the invention is based on a die for a bending or folding device, comprising a base body; at least one pair of bending jaws which are mounted in the base body symmetrically to a center plane of the die about axes parallel to this center plane and which form a flat support surface in the home position and a V-shaped die in the folding position; at least one return element for each bending jaw, which applies a force to the bending jaw towards the home position;at least one sliding element for each bending beam, wherein two sliding elements in each case rest symmetrically to the center plane on the bending beams in the basic position and form a flat, preferably closed support surface for a workpiece parallel to the support surface of the bending beams with flat support sections, and which are arranged such that they can slide parallel to the support surface and transversely to the axis with a workpiece to be machined on the support surface of the bending beam during the bending process, wherein a widened edge section of each sliding element projects further outwards away from the center plane beyond the outer edge of the bending beam facing away from the center plane;

[0009] To achieve the stated objectives, the die according to the invention is characterized by a support section that is rigidly mounted on the sliding element. In the initial position of the bending beam and the sliding element, it rests against a support point on the base body that is stationary during the bending process. In the bending position, it is free of force and lifted from the support point. This avoids spring elements or springy sections of the sliding elements, which not only represent increased structural complexity but can also break or cause other malfunctions that could lead to disruptions in the process and / or damage to the workpiece.

[0010] Preferably, the support section is offset outside the plane of the support section of the sliding element in the direction of the base body and is arranged parallel to the support section offset from the outermost edge of the support section of the sliding element to the center plane.

[0011] A structurally simple solution for providing the sliding element with sufficient mobility is an embodiment according to the invention in which at least one connecting section, preferably concave in the direction of the base body, extends between the outermost edge of the support section of the sliding element and the support section. This shape of the outer section of the sliding element allows it to slide into the die with the workpiece without prematurely hitting the bending beams or associated components.

[0012] An advantageous embodiment with a support section formed by an edge strip of the connecting section arranged perpendicular to the support section results in a large-area contact area between the sliding element and the support section, which ensures a low surface load and can thus significantly reduce or completely prevent damage to the sections of the sliding elements and the support points that come into contact.

[0013] A further embodiment of a die according to the invention is characterized in that a preferably adjustable limiting element is arranged in the area of ​​the articulation of the return element on the bending beam, which defines the outermost position of the sliding element on the bending beam. This limits the sliding elements' displacement away from the center plane of the device, and a consistent starting position for the beginning of the machining process can be reproduced.

[0014] Preferably, the sliding elements are removably attached to the bending beams.

[0015] A further advantageous embodiment of the invention provides that at least one mushroom-shaped fixing element is arranged in the region of the articulation of the return element on the bending beam, and that at least one keyhole-shaped recess is arranged in the region of the support section of the sliding element, matching and cooperating with the fixing element. This secures the sliding elements on the bending beams against accidental falling, while still allowing for simple and quick replacement of the sliding elements if necessary.

[0016] A simple retrofitting of existing devices is the advantage of a further embodiment of a die in which at least one retaining clamp is inserted in the area of ​​the articulation of the return element on the bending beam, to which the limiting element and / or the fixing element is attached or can be attached.

[0017] According to a first embodiment, the retaining clip comprises a first section that has a receptacle for the limiting element or the fixing element. This receptacle is preferably a threaded bore into which a screw can be inserted, acting as a limiting element or fixing element. The first section preferably runs parallel to the support section of the sliding element. The retaining clip further comprises a second section with a connection structure to the bending beam, preferably its spring anchor.

[0018] A particularly quick and easy assembly of the retaining clip is possible with an embodiment in which the second section of the retaining clip has an opening through which the spring anchor of the bending beam can be passed, wherein the second section runs substantially transversely to the first section.

[0019] In the use position, the second section of the retaining clip is preferably located between the bending beam and a transverse bore for suspending the return element. Preferably, fixation is provided by means of the return element suspended in the transverse bore, thus avoiding the need for additional fixing devices.

[0020] The present invention also relates to a complete bending or folding device, comprising at least one die with a base body and at least one pair of bending jaws, which are mounted in the base body symmetrically to a center plane of the die about axes parallel to this center plane, passively pivotable, and which form a flat support surface in the home position and a V-shaped die in the folding position; at least one return element for each bending jaw, which return element applies a force to the bending jaw toward the home position;at least one sliding element for each bending beam, wherein two sliding elements in each case rest symmetrically to the center plane on the bending beams in the basic position and form a flat, preferably closed support surface for a workpiece parallel to the support surface of the bending beams with flat support sections, and which are arranged such that they can slide parallel to the support surface and transversely to the axis with a workpiece to be machined on the support surface of the bending beam during the bending process, wherein a widened edge section of each sliding element projects further outwards away from the center plane beyond the outer edge of the bending beam facing away from the center plane;and at least one punch, which is arranged to be movable along the center plane, for exerting a push-pull force on a workpiece resting on the bending jaws and the sliding elements, thereby causing the bending jaws to pivot and simultaneously bending the workpiece along a bending line lying in the center plane. To achieve the stated object, at least one die of such a device is designed as in one of the preceding paragraphs.

[0021] Advantageously, several dies can also be arranged in a row in a longitudinal direction with a common center plane for bending a workpiece that is longer than a single die. In this case, an advantageous embodiment of the invention provides that at least one sliding element is longer than a single die, preferably equal to or longer than the workpiece.

[0022] For a better understanding of the invention, it is explained in more detail using the following figures.

[0023] They each show in a highly simplified, schematic representation: Fig. 1 the upper area of ​​a die with pivoting bending cheeks, according to the prior art, in a perspective view;

[0024] Fig. 2 shows the upper region of a die according to a preferred embodiment of the invention, with an attached sliding element, in a perspective view;

[0025] Fig. 3 is a vertical cross-section through the die of Fig. 2, perpendicular to the center plane, on the right side with a retaining clip for the sliding element according to a preferred embodiment;

[0026] Fig. 4 a view according to Fig. 2 of a die with secured sliding elements on both bending cheeks as a support surface;

[0027] Fig. 5 shows a vertical cross-section according to Fig. 3 of a bending or folding device with a die according to Fig. 4, in a position at the beginning of the forming process;

[0028] Fig. 6 is a vertical cross-section through a device according to Fig. 5, in a position at the end of the forming process.

[0029] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations, whereby the disclosures contained in the entire description can be applied analogously to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and if the position changes, these positional information must be applied analogously to the new position. For a better understanding of the structure, some elements may be shown not to scale and / or enlarged and / or reduced.

[0030] The die 1 for a bending or folding device comprises a base body 2 in which at least one pair of bending jaws 3 are held. The bending jaws 3 are mounted in the base body 2 symmetrically to a center plane M of the die 1 and are passively pivotable about axes B parallel to this center plane. In the basic position - shown in Fig. 1 - they form a flat support surface 4 for the workpiece W to be machined and in the folding position - see Fig. 5 and Fig. 6 - they form a V-shaped die in the base body 2. At least one return element 5, preferably in the form of a tension spring, is provided for each bending beam 3; advantageously, several return elements 5 are present which act on one and the same bending beam 3, wherein the area of ​​the articulation of the return element 5 on the bending beam 3 is designed, for example, as a pin-shaped spring anchor 3a with a transverse bore for suspending the tension spring used as the return element 5.The return element 5 applies a force to the bending beam 3 which is capable of returning the bending beam 3 from any position rotated about the axis B from the basic position back to the basic position if no other forces act on the bending beam 3.

[0031] As already disclosed in the prior art, at least one sliding element 6 is provided for each bending beam 3 - only one sliding element 6 is shown in Fig. 2 -, wherein two sliding elements 6 are each arranged symmetrically to the center plane M of the die 1, associated with the bending beams 3 which are symmetrically opposite one another with respect to the center plane M of the die 1, in the basic position. The sliding elements 6 - as shown in Fig. 4 - rest on the support surfaces 4 of the bending beams 3 and, with their flat support sections 7, form a flat, preferably closed support surface for a workpiece which lies parallel to the support surface 4 of the bending beams. A widened edge section 8 of each sliding element 6 projects further outwards away from the center plane M beyond the outer edge of the bending beam 3 facing away from the center plane M of the die 1.

[0032] Each sliding element 6 further comprises at least one support section 9, which is rigidly arranged on the sliding element 6, preferably formed integrally with the sliding element 6 as an edge strip arranged perpendicular to its support section 7. The support section 9 lies outside the plane of the support section 7 of the sliding element 6 and is additionally arranged offset in the direction of the base body 2 or in the direction of the center plane M from the outermost edge of the support section 7 of the sliding element 6 to the center plane M. The support section 9 is preferably offset inwards from the edge section 8, in particular from its inner region.

[0033] In order not to impede the mobility of the sliding element 6 parallel to the support surface 4 of the bending cheeks 3 in a functionally disruptive manner, at least one connecting section 10 preferably extends between the outermost edge of the support section 7 of the sliding element 6, i.e. the edge remote from the center plane M, inwards towards the base body 2 and to the support section 9. The connecting section 10 is preferably concavely curved towards the base body 2 so that it can nestle against the outside of the bending cheek 3. The connecting section 10 then merges into the support section 9, which thus forms the edge strip of the connecting section 10.

[0034] As a counterpart to the support section 9 of the sliding element 6, a support point 11 is provided which is stationary at all stages of the machining process of the workpiece. This support point 11, which is stationary at least during the machining process of the workpiece, is preferably arranged on the base body 2 of the die 1 and is formed in particular by its outer side surface, and possibly also by projections, strips, bulges or similar structures. In the basic position of the bending cheek 3 and the sliding element 6 - as shown in Fig. 4 - the support section 9 of the sliding element 6 is in contact with the stationary support point 11 on the base body 2 of the die 1. During the deformation of the workpiece W, i.e. during the bending or folding process, with the bending cheeks 3 rotated about the axis B, the support section 9 is free of forces and is lifted off the support point 11.

[0035] Advantageously, a preferably adjustable limiting element 12 is arranged in the area of ​​the articulation of the return element 5 on the bending beam 3. This limiting element 12 forms a stop for the sliding element 6 during its outward movement, away from the center plane M of the die 1, and thus defines the outermost position that the sliding element 6 can assume on the bending beam 3. At the same time, the limiting element 12, designed, for example, as a screw or rivet with a narrower shaft 13 and a widened or mushroom-shaped head 14, can also serve as a fastening for the sliding element 6.

[0036] Preferably, however, the sliding elements 6 are removably attached to the bending beams 3. A particularly simple and therefore preferred arrangement for the removable, temporary fixation of the sliding elements 6 to the bending beams 3 comprises a fixing element that is mushroom-shaped and widened at the outer end, wherein in the illustrated embodiment, the limiting element 12 also assumes the function of the fixing element. The fixing element - if designed as a separate element - is also positioned in the area of ​​the articulation of the return element 5 on the bending beam 3. In order to fix the sliding element 6 to the bending beam 3, preferably removably, at least one keyhole-shaped recess 15 is preferably arranged in the area of ​​the support section 9 of the sliding element 6, matching and cooperating with each limiting element 12 or fixing element.This recess 15 has a section whose width is slightly larger than the widened part of the fixing element, for example, larger than the diameter of the head 14 of a screw. The recess 15 also has a narrower section whose width is smaller than the diameter of the head 14, but slightly larger than the diameter of the shank 13 of the screw or of any fixing element or limiting element 12. When the sliding element 6 rests on the bending beam 3, the narrower section of the recess 15 lies below the head 14, whereby on the one hand the sliding element 6 is fixed to the bending beam 3 and, at the same time, its outward mobility, away from the center plane M of the die 1, is limited at the underside of the head 14.When the sliding element 6 is lifted perpendicular to the support surface 4 of the bending beam 3, however, the wider section of the recess 15 finally reaches the area of ​​the head 14, so that the sliding element 6 can then be pulled off and removed laterally, ie parallel to the support surface 4, from the limiting element 12 or fixing element and thus from the bending beam 3 after being lifted.

[0037] A simple solution for attaching the limiting element 12 or fixing element, which is also well suited for retrofitting existing devices, can be clearly seen in Fig. 3, but also in Figs. 5 and 6. At least one retaining clamp 16 is inserted in the area of ​​the articulation of the return element 5 on the bending beam 3.

[0038] A first section of the retaining clip 16 has a receptacle for the limiting element 12 or the fixing element and preferably runs parallel to the support section 9 of the sliding element 6. In the basic position of the die 1, this first section of the retaining clip 16 preferably also lies parallel to the lateral surface of the base body 2 of the die 1 and does not protrude beyond the base body 2 at any point. An opening with an internal thread is preferably provided as the receptacle, into which a screw can be screwed as the limiting element 12. Depending on how deeply the screw is screwed into the opening, the lateral limitation for the sliding element 6 can be adjusted.

[0039] A second section of the retaining clip 16 has a connection structure with the bending beam 3. Its spring anchor 3a is advantageously suitable for this purpose, whereby additional components or a more complicated shape of the bending beam 3 can be avoided. Preferably, an opening is machined in the second section of the retaining clip 16 with a width such that the peg-shaped spring anchor 3a of the bending beam 3 fits through and thus the retaining clip 16 can be pushed onto the spring anchor 3a. The angle between the first and the second section of the retaining clip 16 depends on the position of the spring anchor 3a. Typically, these sections run at an angle between 60° and 90°, preferably between 75° and 90°, which results in a retaining clip 16 that is hook-shaped in longitudinal section.

[0040] In order to securely connect the retaining clip 16 to the bending beam 3 even without additional fastening means, the second section of the retaining clip 16 is arranged in the use position between the bending beam 3 and a transverse bore in the spring anchor 3a for suspending the return element 5. The thickness of the second section of the retaining clip 16 must be selected accordingly to enable this positioning. After suspending the return element 5 into the transverse bore of the spring anchor 3a, the retaining clip 16 is secured against slipping off the spring anchor 3a and is securely connected to the bending beam 3, yet can still be removed after the return element 5 is removed.

[0041] A bending or folding device according to the invention comprises, in addition to at least one die 1 in one of the embodiments described so far, at least one upper tool or at least one punch 17 which is arranged to be movable along the center plane M. By means of this punch 17, as can be seen in the snapshots of Fig. 5 and Fig. 6 from the process sequence, a compressive and pushing force can be exerted on a workpiece W when lowered onto the die 1, which workpiece rests on the bending cheeks 3 and the sliding elements 6. At the beginning of the bending or folding process, the sliding elements 6 are still parallel to one another and are in their furthest outward position from the center line M. This also applies after the first, slight deformation of the workpiece W, with a still slight rotation of the bending cheeks 3 about the axes B.

[0042] As the punch 17 continues to be lowered, the bending cheeks 3 are increasingly pivoted and finally form a V-shaped die in the die 1, into which the workpiece W is pressed by the punch 17 and bent or folded along a bending line lying in the center plane M. As the workpiece W is deformed, i.e. as the depth of insertion of the punch 17 increases, the sliding elements 6 are carried along due to the friction between the workpiece W and the sliding element 6 and slide along the support surfaces 4 of the bending cheeks 3 in the direction of the center plane M. In contrast, there is no or only a slight relative movement between the workpiece W and the sliding elements 6. As a result, the support sections 9 also move away from the underside of the widened section of the limiting element 12 and approach the side of the bending cheek 3 and the side of the base body 2 of the die 1.

[0043] However, since no other elements of the arrangement act on the sliding element 6 and the support section 9, and in particular no forces parallel to the support surfaces 4 of the bending beams 3 act on the support section 9, the sliding elements 6 can move in an optimal manner adapted to the deformation of the workpiece W. Disturbances in the movement sequence, blocking of the sliding elements 6 on the bending beams 3 and resulting damage to the workpiece W, as well as damage to the device due to broken additional components can thus be reliably avoided.

[0044] When the device is returned after completion of the machining process and removal of the workpiece W from the bending cheeks 3 and the sliding elements 6, from the position shown in Fig. 6 back to the position shown in Fig. 4, the bending cheeks 3 are rotated back into their home position by the action of the return elements 5. During the rotation, the support sections 9 of the sliding elements 6 finally come to rest against the support sections 7 on the base body 2. Upon further rotation of the bending cheeks 3 towards the home position, the support section 7 fixes the sliding element 6 in such a way that the bending cheek 3 can continue to rotate under the held sliding element 6 and the two parallel sections of the sliding element 6 and the bending cheek 3 can slide past each other.

[0045] For workpieces W that are longer than a single die 1, several dies 1 can be arranged in a row, aligned in a longitudinal direction with a common center plane M. In this case, an advantageous embodiment provides a device in which at least one sliding element 6 is longer than a single die 1, preferably equal to or longer than the workpiece W.

[0046] The scope of protection is determined by the claims. However, the description and drawings must be used to interpret the claims. Individual features or combinations of features from the various embodiments shown and described may represent independent inventive solutions. The problem underlying these independent inventive solutions can be derived from the description.

[0047] Reference symbol list

[0048] 1 die

[0049] 2 basic bodies

[0050] 3 bending beam

[0051] 4 Support surface

[0052] 5 Reset element

[0053] 6 Sliding element

[0054] 7 support section

[0055] 8 Edge section

[0056] 9 Support section

[0057] 10 Connection section

[0058] 11 Support point

[0059] 12 Limiting element

[0060] 13 shaft

[0061] 14 heads

[0062] 15 Recess

[0063] 16 retaining clip

[0064] 17 stamps

[0065] B axis of rotation

[0066] M Middle level

Claims

P a t e n t a n s p r ü c h e 1. Die (1) for a bending or folding device, comprising a base body (2); at least one pair of bending jaws (3) which are passively pivotable in the base body (2) about axes (B) lying parallel to a central plane (M) of the die (1) symmetrically to this central plane (M), and which form a flat support surface (4) in the home position and form a V-shaped die in the base body (2) in the folding position; for each bending jaw (3) at least one return element (5) which applies a force to the bending jaw (3) towards the home position;at least one sliding element (6) for each bending jaw (3), wherein two sliding elements (6) in the basic position rest symmetrically to the central plane on the bending jaws (3) and with flat support sections form a flat, preferably closed support surface for a workpiece parallel to the support surface of the bending jaws (3), and which are arranged so that they can slide parallel to the support surface and transversely to the axis with a workpiece to be processed on the support surface of the bending jaw (3) during the bending process, wherein a widened edge section of each sliding element (6) projects further outwards from the central plane beyond the outer edge of the bending jaw (3) facing away from the central plane;characterized by a support section (9) which is rigidly arranged on the sliding element (6), in the basic position of the bending cheek (3) and the sliding element (6) rests against a support point (11) on the base body (2) which is stationary at least during the bending process and is lifted from the support point (11) without force in the bending position.

2. Die (1) according to claim 1, characterized in that the support section (9) is offset outside the plane of the support section (7) of the sliding element (6) in the direction of the base body (2) and is arranged parallel to the support section (7) offset from the outermost edge of the support section (7) of the sliding element (6) towards the central plane (M).

3. Die (1) according to claim 2, characterized in that at least one connecting section (10) which is preferably concave in the direction of the base body (2) extends between the outermost edge of the support section (7) of the sliding element (6) and the support section (9).

4. Matrix (1) according to claim 3, characterized in that the support section (9) is formed by an edge strip of the connecting section (10) arranged perpendicular to the support section (7).

5. Die (1) according to claim 4, characterized in that in the area of ​​the pivoting of the return element (5) on the bending cheek (3) a preferably adjustable limiting element (12) is arranged which defines the outermost position of the sliding element (6) on the bending cheek (3).

6. Die (1) according to claim 5, characterized in that the sliding elements (6) are detachably attached to the bending cheeks (3).

7. Die (1) according to claim 6, characterized in that at least one mushroom-shaped fixing element (12) is arranged in the area of ​​the pivot point of the return element (5) on the bending cheek (3), and that at least one keyhole-shaped recess (15) matching and thus cooperating with the fixing element (12) is arranged in the area of ​​the support section (10) of the sliding element (6).

8. Die (1) according to claims 5 to 7, characterized in that at least one retaining clip (16) is inserted in the area of ​​the pivot point of the return element (5) on the bending cheek (3), to which the limiting element (12) and / or the fixing element is or can be attached.

9. Die (1) according to claim 8, characterized in that the retaining clip (16) comprises a first section which has a receptacle, preferably a threaded bore, for the limiting element (12) or the fixing element, wherein the first section preferably runs parallel to the support section (9) of the sliding element (6), and that a second section of the retaining clip (16) has a connection s structure with the bending cheek (3), preferably its spring anchor (3a).

10. Die (1) according to claim 9, characterized in that the second section of the retaining clip (16) has an opening through which the spring anchor (3 a) the bending cheek (3) can be passed through, with the second section running essentially perpendicular to the first section.

11. Die (1) according to claim 10, characterized in that the second section of the retaining clip (16) is located in the operating position between the bending jaw (3) and a transverse bore for hooking the return element (5), and that preferably a fixation is provided by means of the return element (5) hooked into the transverse bore.

12. Bending or folding device comprising at least one die (1) with a base body (2) and at least one pair of bending jaws (3), which bending jaws (3) are passively pivotable in the base body (2) symmetrically to a median plane of the die (1) about axes (B) lying parallel to this median plane (M), and which in the home position form a flat support surface (4) and in the bending position form a V-shaped die in the base body (2); at least one return element (5) for each bending jaw (3), which return element (5) applies a force to the bending jaw (3) towards the home position;at least one sliding element (6) for each bending jaw (3), wherein two sliding elements (6) in the basic position rest symmetrically to the central plane (M) on the bending jaws (3) and with flat support sections (7) form a flat, preferably closed support surface for a workpiece (W) parallel to the support surface (4) of the bending jaws (3), and which are arranged so that they can slide during the bending process parallel to the support surface (4) and transversely to the axis (B) with a workpiece (W) to be processed on the support surface of the bending jaw (3), wherein a widened edge section of each sliding element (6) projects further outwards from the central plane (M) beyond the outer edge of the bending jaw (3) facing away from the central plane (M);and at least one punch (17) which is movably arranged along the central plane (M) to exert a push-slide force on a workpiece (W) which rests on the bending jaws (3) and the sliding elements (6) in order to cause the bending jaws (3) to pivot and simultaneously to bend the workpiece (W) along a bending line lying in the central plane (M), characterized in that at least one die (1) is configured according to one of claims 1 to 11.

13. Device according to claim 12, wherein several dies (1) are arranged in a row in a longitudinal direction with a common central plane (M), for bending a workpiece (W) that is longer than a single die (1), characterized in that at least one sliding element (6) is longer than a single die (1), preferably the same length or longer than the workpiece (W).

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