EP2814627B1 - Bending press with adjustable beam element - Google Patents

Description

The invention relates to a bending press as described in the preamble of claim 1.

When reshaping workpieces with relatively large dimensions, the problem often arises, in particular when folding, that the pressing beam of a bending machine bends due to high forming forces and curved workpieces have non-uniform bending angles along the forming edge. In addition to the ability to increase the rigidity of the forming forces receiving components, other approaches are already known to reduce the adverse effects of machine deformation.

Out WO 01/43896 A1 a press brake for producing bent-formed workpieces is known, comprising a fixedly arranged on a machine frame table beams, a relative thereto by means of a drive assembly and in guide assemblies on the machine frame adjustable pressing beams and on opposite support surfaces of the table beam and the press bar arranged tool holders with bending tools. The arranged on the machine frame table joists extending from lateral edges in the direction of the center of the table beam slot-shaped recesses extending over portions of the length of the table beam and in which symmetrically to the center of the table and at their distance simultaneously adjustable spacer elements are arranged. Depending on the positioning of the spacer elements, the table beam above the recesses on a variable deformation resistance and the occurring during a pressing process deflection of the pressing beam center can be compensated for upward by a corresponding deflection of the ends of the table beam down.

From the document US 5,426,966 A is a bending press with a fixed table bar and a relative to the tabletop adjustable means of drive means pressing beam known. The press beam is formed in two parts, wherein a first beam part is drivingly connected to the drive means and a table beam facing, another beam part is drivingly connected in the region of a central axis via a flexible connecting element with the first beam part. Starting from this connecting element run between the first beam part and the second beam part in the direction of the opposite end portions of conically widening slots. At the end regions, the slots are provided with wedge-shaped extensions in which spacer elements are arranged to be adjustable perpendicular to a central axis, wherein depending on their position a bending deformation occurring under load of the press beam during a forming process can be counteracted.

Out US 4,426,873 A is a bending press with a arranged on a support surface of a table beam, a tool holder for the bending tool carrying over an entire length of the press beam extending adjusting device for a variable design of a longitudinal embossing of a footprint for the tool holder known. The adjusting device is essentially formed by a wedge-shaped in cross-section longitudinal profile, which is divided by cuts in wedge sections and thus has a flexibility in a plane perpendicular to a bending plane extending. By appropriate adjustment of the wedge sections in the plane of a crowning of the support surface of the tool holder for compensating a bending deformation occurring under load of the table beam is achieved on the profile.

Furthermore, it is off DE 37 09 555 A1 a device is known in which for setting up a pressing tool in a convex state between the lower pressing tool and the press table at intervals along the longitudinal direction of the press brake, a plurality of pairs of upper and lower wedges are arranged. A coordinated displacement movement of the wedges is achieved via a, acted upon by a control drive, extending over the entire length of the press brake, elastic spring element, whereby a support surface for the tools or a receiving device for the tools occupies a tailored to the requirements curvature and thus a compensation for the bending of the table beam and / or press beam is achieved over an entire bending length and so the immersion depth of the bending tools over the entire bending length is approximately equal. However, the production of the wedge pairings and the displacement mechanism is structurally very complex.

The object of the invention is to provide a bending press, in which a support surface for bending tools on a press table or pressing beam with structurally simple embodiment is actively changeable in its course. The object of the invention is achieved by a generic bending press with the characterizing features of claim 1.

Characterized in that the support structure has at least one elongate support member which can take at least partially a helix angle with respect to the adjustment direction of the press beam, and the actuating device comprises a transversely to the adjustment on the support structure, in particular the support member acting actuator, with the helix angle of the support member can be changed within the table and / or press beam, it is possible to optimally adjust the course of the support surface to the deflections caused by the deformation of the bending press, whereby uneven degrees of deformation of the workpiece and thereby caused geometric errors can be substantially reduced. Such support elements are very simple components and the manufacturing cost of such a bending press is relatively low. The adjustment can be made so that the helix angle is increased by the actuator, either starting from an initially absent skew or relatively small skew or is reduced starting from an initially existing skew. The helix angle of a support element can therefore be present either before the adjustment by the actuator or only after the adjustment by the actuator.

The oblique portions of the support member cause a greater elastic mobility and it can be relatively easily adjusted by means of the actuators, the inclination and thus the crown height of the support surface. The desired course of the support surface can be adjusted before the start of a forming process, but the design of the actuator allows an active adjustment of the curve even during a forming process. As actuators here are systems that correspond to the drive means of the press beam so for example hydraulic cylinders or servomotors with adjusting spindles. Thus, the existing press control can be easily supplemented by the control of the actuators. The angular displacement of the at least one support element by the at least one actuator and the resulting curvature of the support surface can be adapted to the deflection of the press beam in various ways. So it is possible, for example, that the expected maximum forming force is calculated in advance and based on a determined in test series dependence between forming force and Pressbalkendurchbiegung the required curvature of the support surface and thus the required Angle adjustment of the support element before reaching the maximum forming force or already made before the start of the forming. Alternatively, it is also possible that by means of suitable sensors, such as strain gauges or on the detection of the current forming force, for example via the hydraulic pressure or the drive current of the drive means, which is measured during a forming process currently occurring deflection of the press beam or calculated and the press table by adjustment the supporting element is actively set during the forming process a curvature of the support surface corresponding to the respective current value of the deflection.

The at least one support element is not only actively adjusted by the actuator in its helix angle, it is also possible during a bending operation to use the actuator in such a way that an unwanted deformation of the beam element by the forming forces and thereby caused too strong spring back of a support member by the Aktuatorkraft counteracted. The actuator preferably has a holding function with which e.g. a retraction of a hydraulic piston can be blocked or a parking brake. Furthermore, it is possible that the actuator counteracts by means of a position control and a controlled increase in the actuating forces of an unwanted deformation of the support structure.

Preferably, the respective deformation state of the press beam, preferably also the support structure by means of suitable sensors, e.g. Strain gauges are detected and based on the corresponding activation of the actuators done.

If the support structure comprises a plurality of inclined support elements, the beam element can be actively changed at a plurality of support points and the curve of the support surface can be more uniform. The adjustment of the support elements can be effected by means of an actuator, but preferably by a plurality of actuators, whereby the adjustment movements of the individual support elements can be varied and independent of each other influenced. By means of a plurality of support elements, it is further possible to optimally compensate for asymmetrical deflections of the press beam, which can occur in off-center bending operations, by means of a corresponding asymmetrical adjustment of the support elements. The required curvature or crowning of the support surface can In this case, suitable for a pre-calculated or measured during the forming process directly or indirectly measured deflection of the press bar can be produced.

The support elements of a support structure may also be formed from a plurality of spring plates, which are provided in a corresponding number and with corresponding cross sections. The spring plates can be connected with their ends relatively rigid or even relatively articulated to the beam member or a base member. A rigid version of the attachment may e.g. in that the ends are inserted in grooves or slots which extend horizontally and transversely to the adjustment of the adjustable pressing beam.

Preferably, the helix angles of all inclined support elements lie within a plane and parallel to the adjustment plane of the press beam. The adjustment movements can thereby also take place within a plane, which is structurally simpler with an elongated beam element and the depth of the press table or beam is not substantially increased by the actuators and support elements. Due to the arrangement of the helix angles in one plane, the adjustment forces of the actuators are also essentially in one plane, and a plurality of support elements can be adjusted in a simple manner by means of an actuator.

In order to avoid undesirable deflection of the oblique support elements transversely to the adjustment plane of the press beam, it is advantageous to guide them between two parallel to the adjustment plane of the press bar guide plates or aprons with little play. The requirements for the rigidity of the support elements transversely to the adjustment are thereby lower. Further, by the guide plates, the rigidity of the beam member can be increased when these are fixedly connected to beam member e.g. are bolted, whereby the beam element point loads, resulting from bending operations on short tool stations can provide sufficient rigidity and no local deformations occur.

To further increase the guide plates or aprons may be connected to each other at their distant from the beam element edges by means of a lower chord or with a arranged from the beam element after the support element arranged base element to be fixed, which as well as a lower flange, the rigidity of the beam element can further increase local deformations due to punkartiger loads during bending operations are avoided.

Increased elasticity and thus easier adjustability of the support elements is achieved if a longitudinal dimension of the at least one support element in its support direction corresponds to at least three times its cross-sectional dimension in the direction parallel to the beam element.

In order to avoid forces acting in the longitudinal direction of the beam element, it is advantageous if a displacement bearing movable in the longitudinal direction of the beam element is formed between the support element and the beam element or between the support element and the base element which forms the stationary part of the support structure. The second variant is provided if the actuator engages the distanced from the beam element end of the support element.

For the common designs of press beams with symmetrical arrangement of the drive means and symmetrical arrangement of the guides on the machine frame, it is advantageous if the support elements and the actuators are arranged symmetrically with respect to a longitudinal axis of the beam element perpendicular center plane of the press brake.

An easily manufactured and particularly stable embodiment of a support structure can be produced when a plurality of adjacent support elements are formed by introduced into a plate-like base member of the table or the press beam inclined slots, wherein the slots completely pass through the base member. These slots can be introduced, for example, by laser cutting economically and flexibly modifiable.

The course of the support surface, which arises upon activation of the actuators, can also be adapted to the deformation behavior of the press beam by the support structure comprises a plurality of obliquely extending support elements with different sized cross-sectional areas and / or the support structure a plurality of inclined support elements with respect to the adjustment different Includes helix angles. A locally stronger adjustment of the beam element at the same adjustment of the actuator can be achieved by a arranged in this zone support member with a larger helix angle. Support elements with smaller cross-sectional areas have a higher elasticity and can such be provided where a greater compliance of the beam element is desired.

For bending presses in which the drive means for the forming operation engage the end portions of the pressing beam, it is advantageous if the helix angles of support members in the central portion of the beam member are greater than those of support members located closer to the end portions, as in this most common drive form of a pressing beam the crowning or raising of the curve of the support surface in the middle is most required and this can be achieved by the centrally larger helix angle, even if all the support elements of the same horizontal adjustment path is impressed.

A simple production of a beam element and calculation of the curve and the required adjustments of the support elements is possible if the beam member has a substantially constant bending stiffness over its entire length.

A good relationship between sufficient adjustability and sufficient rigidity of the support structure is achieved when the helix angle of the support member or the support elements with respect to the adjustment is between 0 ° and 45 °, wherein the effect according to the invention can be realized in a support element oriented in the adjustment that this is moved from the vertical base position by the actuator in an oblique position, whereby the beam element can be locally lowered or raised. Larger helix angles result in an unfavorable force transmission, if the force introduction direction of the actuator is approximately in the horizontal direction, but a stronger vertical adjustment of the supported beam element. For small helix angles, however, a good force transmission or a toggle effect can be achieved.

If adjacent support elements are oriented obliquely oriented in the same direction within a subsection of the beam element, a larger number of support elements can be accommodated on a short subsection of the beam element than in the case of alternating orientation.

A largely smooth course of the support surface and avoiding the introduction of force in the longitudinal direction of the beam element is achieved when the support element or the support elements is formed with respect to a symmetrical to the adjustment symmetry plane in the form of a herringbone pattern substantially symmetrical with two opposite in relation to the adjustment of the press beam inclined sections or are and the force introduction direction of the actuator or the actuators is located substantially in the plane of symmetry of the support element. By substantially mutually parallel support elements within such a structure, a large number of adjustable support elements can be accommodated in a small space. The individual support elements in this case have to absorb only a small portion of the forming forces and can have smaller cross sections.

An alternative embodiment having similarly advantageous effects results when the support structure comprises a plurality of support wires formed from support elements with oblique support sections and the force introduction direction of the actuator lies substantially in the plane of symmetry of the support rails perpendicular to the adjustment direction.

If in each case a separate actuator is provided between adjacent support rods, horizontal displacements of the connection points on the beam element or on the base element can be prevented and a displacement bearing at the upper and lower ends of the support elements can be dispensed with here.

A simple embodiment of a support structure results when at least one oblique support element connected to the actuator is arranged in the middle section of the beam element and the support structure at the end sections of the beam element has a higher rigidity in the adjustment direction than the oblique support element not force-urged by the actuator. For applications in which a workpiece is bent in the middle section beam element, this simple construction, the harmful deflection of the press beam can be largely compensated.

An embodiment also with a low number of support elements can consist in that at least two oblique support elements connected to an actuator are arranged at the end portions of the beam element and the support structure in the middle section of the Beam element has a higher rigidity in the adjustment direction, as the non-force actuated by the actuators oblique support elements.

To avoid or reduce bending moments and multiaxial stress states within the support structure, it is advantageous if the at least one support element is mounted with at least one end on the beam element, on the support structure, on the table or on the pressing beam by means of a joint or bearing. In particular pivot bearings or slide bearings can be used as joints.

The number of components required for a support structure is reduced if the at least one support element is integrally formed with at least one end on the beam element, on the support structure, on the table or on the pressing beam.

The number of actuators can be reduced or kept low even when installing a plurality or many support elements by a support element or more support elements with an actuator only indirectly with the interposition of another support member is in connection or stand.

The forwarding of the adjustment forces exerted by the actuators can advantageously be effected by webs or support elements arranged between adjacent support elements for the mutual transmission of force.

In order to be able to adapt the curve of the support surface flexibly to the application of the dependent bending of the press beam, it is advantageous if a plurality of actuators acting transversely to the adjustment on the support elements are arranged in the support structure. which are controlled by a control of the bending press and individually or at least in groups with different adjustment can be activated.

For a better understanding of the invention, this will be explained in more detail with reference to the following figures.

Fig. 1

eine Gesamtansicht einer Biegepresse mit einer möglichen Ausführungsform einer Stelleinrichtung und Stützstruktur zur aktiven Verstellung einer Stützfläche;

Fig. 2

eine Ansicht eines Presstisches mit einer möglichen Ausführungsform einer Stelleinrichtung und Stützstruktur;

Fig. 3

eine Ansicht eines Presstisches mit einer weiteren möglichen Ausführungsform einer Stelleinrichtung und Stützstruktur;

Fig. 4

einen Ausschnitt aus einer weiteren möglichen Ausführungsform einer Stützstruktur mit einem gewinkelten Stützelement;

Fig. 5

einen Ausschnitt aus einer weiteren möglichen Ausführungsform einer Stützstruktur mit Stützelementen in Form einer Fischgrätstruktur;

Fig. 6

eine Ansicht einer weiteren möglichen Ausführungsform einer Stelleinrichtung und Stützstruktur mit rautenförmig angeordneten Stützelementen;

Fig. 7

einen Schnitt durch einen Presstisch mit einer Stelleinrichtung und einer in Fig. 6 dargestellten Stützstruktur;

Fig. 8

eine Ansicht einer weiteren möglichen Ausführungsform einer Stelleinrichtung und Stützstruktur mit geraden Stützelementen und einem Verschiebelager zum Ausgleich von Horizontalverschiebungen der Stützelemente und

Fig. 9

eine Ansicht einer weiteren möglichen Ausführungsform einer Stelleinrichtung und Stützstruktur mit abgewinkelten Stützelementen in Fischgrätstruktur.

Each shows in a highly schematically simplified representation:

Fig. 1

an overall view of a bending press with a possible embodiment of an actuating device and support structure for active adjustment of a support surface;

Fig. 2

a view of a press table with a possible embodiment of an actuating device and support structure;

Fig. 3

a view of a press table with another possible embodiment of an actuating device and support structure;

Fig. 4

a section of another possible embodiment of a support structure with an angled support member;

Fig. 5

a section of a further possible embodiment of a support structure with support elements in the form of a herringbone structure;

Fig. 6

a view of another possible embodiment of an actuating device and support structure with diamond-shaped support elements;

Fig. 7

a section through a press table with an adjusting device and a in Fig. 6 illustrated support structure;

Fig. 8

a view of another possible embodiment of an actuating device and support structure with straight support elements and a sliding bearing to compensate for horizontal displacements of the support elements and

Fig. 9

a view of another possible embodiment of an adjusting device and support structure with angled support elements in herringbone structure.

By way of introduction, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numerals or the same component names, wherein the disclosures contained in the entire description can be mutatis mutandis to the same parts with the same reference numerals or component names. Also, the location information selected in the description, such as above, below, laterally, etc. related to the immediately described and illustrated figure and are to be transferred to a new position in a change in position. Furthermore, individual features or combinations of features from the different exemplary embodiments shown and described can also represent independent, inventive or inventive solutions.

All statements on ranges of values in the description of the present invention should be understood to include any and all sub-ranges thereof, e.g. the indication 1 to 10 should be understood to include all sub-ranges, starting from the lower limit 1 and the upper limit 10, i. all subregions begin with a lower limit of 1 or greater and end at an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1 or 5.5 to 10.

Fig. 1 shows a front view of a bending press 1 in the form of a press brake, based on which the inventive principle is explained.

The bending press 1 comprises a machine frame 2, with which a fixed table 3 is connected. The machine frame 2 is further supported by means of guide assemblies 4 a vertically adjustable pressing bar 5, wherein the adjustment is effected by drive means 6, for example in the form of hydraulic cylinders. The machine frame 2 comprises, in a common embodiment, two spaced-apart side cheeks 7, for example in the form of C-stands, which are connected by means of transverse connectors 8. At the table 3 and the pressing bar 5 are opposing or mutually facing support surfaces 9 and 10 are formed, on which cooperating bending tools 11 and 12 can be arranged. The bending tools can also be attached by means of their own tool receiving devices, the execution of the bending tools themselves or any adapter or tool holders is not relevant to the subject of the invention.

A common form of the bending tools is an arrangement of a bending die on the support surface 9 of the table 3 and the attachment of a punch on the support surface 10 of the press beam 5. When approaching the press bar 5 to the table 3 can by cooperating Bending tools 11 and 12 forming forces are exerted on an inserted therebetween workpiece 13, whereby this is subjected to a bending deformation.

The support surface 9 on the table 3 is thereby formed by a beam element 14 on the table 3 and the upper support surface 10 by a beam element 15 on the pressing beam 5. The beam elements 14 and 15 extend over the total length 16 of the table 3 and the press beam 5, whereby the bending tools 11, 12 can be selected and positioned according to the requirement of the workpieces 13 to be bent.

As in Fig. 1 shown, cause the forming forces occurring during a pressing process a deflection 17 of the press beam, which is problematic especially for long workpieces 13, as along the forming zone, here the bending edge, no uniform degree of deformation is given and therefore an uneven deformation is possible. Thus, with a folded workpiece 13, the bending angles at the outer ends of the bending edge do not coincide with the bending angle in the middle of the bending edge.

In order to prevent or reduce this disadvantageous effect, it is provided in the bending press 1 according to the invention, on the opposite support surface 9 on the table 3 to create a corresponding bow 17 corresponding to the curve 18. This results in a uniform degree of deformation of a workpiece to be bent 3 along the bending edge and a uniform, constant bending angle is achieved in a press brake.

The lower beam element 14 on the table 3 is supported by a support structure 19 of the table 3 and an adjusting device 20 is arranged in the table 3, with which this cambered course 18 of the beam element 14 can be effected. The lower beam member 14 and the upper beam member 15 extend by this measure under the influence of forming forces at a constant distance, with the maximum deflection of the press beam at a total length 16 of the table 3, for example, 2500 mm in the range of a few millimeters, for example a maximum of 3 mm moves , The deflection of the press beam 5 with the upper beam element 15 results essentially in the adjustment direction 21 of the press beam 5 and in the adjustment plane, which in Fig. 1 corresponds to the drawing plane.

In order to produce such a cambered course 18, the lower beam element 14 must be raised slightly upwards in the middle region upwards against the pressing direction, that is, in the illustrated embodiment, at least at the conclusion of the pressing process or forming process. The amount by which the lower beam element 14 must be raised can be calculated in advance by a controller in a good approximation, based on the known deflection behavior of the press beam 5, or the corresponding values for the required crowning of the lower beam element 14 can be known on the basis of series of tests on specific load situations be.

The support structure 19 has an elongate support element 22, which has a helix angle 23 with respect to the adjustment direction 21 of the press beam. In order to be able to actively effect a displacement of the beam element 14, the adjusting device 20 comprises an actuator 24, for example in the form of a hydraulic cylinder, with which the helix angle 23 of the support element 22 within the table 3 can be changed. As in Fig. 1 is easy to see causes a reduction of the helix angle 23, a lifting of the beam member 14, whereby the cambered profile 18 is effected.

In Fig. 1 For the sake of simplicity, only an oblique support element 22 is shown, which acts like a point load from below on the beam element 14; However, in order to obtain a continuous and the deflection 17 of the press beam 5 corresponding cambered course 18, advantageously, a plurality of oblique support members 22 may be provided, the helix angle 23 by means of at least one actuator 24 can be changed. The support element 22 is at least slightly displaceable by its elongated design within the support structure 19 and the elongated embodiment is to be understood such that a longitudinal dimension of the support member 22 is greater than its dimension transverse to its longitudinal axis and in the direction of its slight displacement. Preferably, the longitudinal dimension of the support element 22 is more than three times its cross-sectional dimension in the longitudinal direction of the beam element 14.

The actuator 24 acts in the illustrated embodiment directly on the support member 22 and in turn is supported on the rest of the support structure 19, which are considered in the illustrated embodiment in comparison to the support member 22 as rigid and immovable can. That part of the supporting structure 19, on the table 3 or on the pressing beam 5, which can essentially be regarded as rigid, may also be referred to as the base section. The beam elements 14 and 15 are executed in the illustrated embodiment as separate components, but may also be an integral with the table 3 or pressing beam 5 related element. The longitudinal axis 25 of the support member 22 has with respect to the adjustment direction 21 a helix angle of preferably between 10 ° and 45 °, depending on the actual helix angle 23 different effects come to bear more. At a smaller helix angle 23 results in a good power transmission, that is, with relatively little force of the actuator 24, a high biasing force can be achieved on the beam member 14. If a relatively large helix angle 23 is selected, a better movement ratio is achieved, that is to say a small adjustment path on the actuator 24 causes a relatively large, vertical adjustment path for the prestressing of the beam element 14.

The deflection 17 of the beam element 15 during a forming process will in many cases be substantially symmetrical with respect to a longitudinal plane of the beam element 14 perpendicular extending center plane 26 of the bending press 1 and it is therefore advantageous if the adjusting device 20 with the inclined support elements 22 so executed is that the cambered profile 18 of the lower beam member 14 is also effected symmetrically to the center plane 26. In Fig. 1 a very simplified embodiment of a support structure 19 is shown with a sloping support member 22, and are shown in sequence various embodiments of support structures 19, with which using a transverse to the adjustment 21 of the press beam acting on the support structure 19 actuator 24 a cambered course 18 of a Beam element 14 can be achieved.

The use of a support structure 19 with actively adjustable, inclined support member 22 is not limited to a table 3, but can of course also be used on a press bar 5 to a caused by the forming forces bending of the press bar 5 ddddurch an opposite, active deformation of the beam element 15 balance. Accordingly, the above and following embodiments are also to be interpreted for embodiments of bending presses 1 in which such oblique support elements 22 are provided only on the table 3 or only on the pressing bars 5 or both on the table 3 and on the pressing bar 5.

The support structure 19 includes in certain embodiments as a fixed part next to the adjustable support members 22 lein plate-like base member 27, such as those are also used in known from the prior art bending presses 1 both for the press table and for the pressing beam. However, columnar embodiments of support structures 19 are also conceivable, which likewise include oblique support elements 22 and actuators 24 acting thereon.

An important effect of an oblique support element 22 is the comparatively great mobility in the adjustment direction 21, which is greater than in the case of support elements which are arranged parallel to the adjustment direction 21. This mobility is used in conjunction with the actuator 24 to bias a beam member 14 accordingly.

The illustrated embodiments of support structures with oblique support members 22 may, as already described, by active reduction of the helix angle 23 a cambered profile 18 of the respective beam element 14 and 15 cause, but it is also possible by actively increasing the helix angle 23, a beam element 14 locally lower or to produce a concave profile 19. This could be applicable, for example, if the upper press beam 5 only comprises a drive means 6 in its central region.

At the in Fig. 1 In the illustrated embodiment, the lower end of the support element 22 is integrally formed on the base member 27 of the table 3, that is, the support member 22 is elastically deformed upon activation of the actuator 24 relative to the rest of the table 3 and the base member 27 and thereby the beam member 14 in the cambered History 18 brought. This deformation of the oblique support member 22 is made possible or substantially facilitated by its elongated embodiment.

In Fig. 2 is a simplified view of a similar embodiment of a support structure 19 on a table 3 and a press bar 5 in a partial view of a bending press 1 shown. In this embodiment, as in the previously described in the central region 28 of the beam member 14 and 15, a sloping support member 22 is arranged, which can be changed by means of an actuator 24 in its helix angle 23. The end sections 29 of the beam element 14 or 15 are supported by a part of the support structure 19, which have a higher rigidity in the adjustment direction 21 at the end sections 29 than the inclined support element 22. The inclined support element 22 arranged in the middle region 28 can, as already described above, be replaced by a plurality of such inclined support members 22, 22 ', ....

If the actuator 24 exerts a compressive force to the left, the support element 22 is moved to a steeper position, thereby slightly raising the beam element 14 in its middle region 28. Since this adjustment of the support member 22 shifts its upper end not only in the vertical direction but also in the horizontal direction, it is in such an arrangement of the support member 22 is advantageous if, as in Fig. 2 illustrated, between the upper end of the support member 22 and the beam member 14 is a movable in the longitudinal direction of the beam member 14 sliding bearing 30 is formed. With the in Fig. 2 It is also possible to make a concave profile 18 ', for example by the actuator 24 pulling the upper end of the support element 22 to the right or to the left of the upper end of the support element 22 and increasing the helix angle 23 of the support element 22 by applying a compressive force , whereby its upper end is slightly lowered.

In Fig. 3 is a partial view of another embodiment of a support structure 19 for a beam element 14 of a bending press 1 is shown. The two end portions 29 of the beam member 14 are supported by obliquely extending support members 22, while the central portion 28 is supported by the rest of the support structure 19 and in the central portion 28 has a higher rigidity in the adjustment direction 21, as the inclined support members 22. The two support members 22 can be adjusted by actuators 24 in their position relative to the base portion 27 and with respect to the rest of the support structure 19 in its helix angle 23, whereby the end portions 29 of the beam member 14 can be actively adjusted. Again, it is possible depending on the operation of the actuators 24 and their arrangement, as already based on Fig. 2 described to achieve a concave or a convex course of the support surface 9 on the beam element 14. Before being adjusted by the actuators 24, the support elements 22 can also have a helix angle of 0 ° with respect to the adjustment direction 21, which can be increased by the actuators 24 and thereby the beam element 14, 15 is adjusted.

In the Fig. 3 illustrated variant could also be modified to the effect that the support elements 22 are slidably mounted at its lower end relative to the base member 27 by means of sliding bearings 30 and the actuators for lowering the lateral ends of the beam member 14, 15 at the lower end of the support elements 22 attack and in the direction of vertical mid-plane pressure forces can exercise.

In Fig. 3 is further indicated by dashed lines on the right support member 22 that it can also assume a helix angle of 0 ° in the normal position, which can be increased by the actuator 24, whereby also the course of the support surface 9, 10 can be actively changed.

In Fig. 4 a detail of a further embodiment of a support structure 19 is shown, with which a beam element 14 can be adjusted under the action of an actuator 24 between a flat and a convex or concave curved course by a support member 22, which the beam member 14 relative to the rest of the support structure 19 that is, the base member 27, the rest of the table 3 or the press bar 5, supported and can be adjusted in its helix angle 23 by the actuator 24.

The support element 22 has according to Fig. 4 two oblique sections 31 and 32, which extend obliquely with respect to the adjustment direction 21, wherein the helix angle 23 of the two inclined sections 31 and 32 in opposite directions with respect to the adjustment direction 21. The support member 22 is thus V-shaped and the two free ends of the V-angle with the beam member 14 and the base member 27 are connected. As Fig. 4 shows, the two inclined portions 31 and 32 of the support member 22 may be connected to each other by means of a hinge 33, as well as the other ends of the inclined portions 31 and 32 may be articulated by means of joints 33 on the base member 27 and the beam member 14. Of course, it is also possible that between the two inclined sections 31 and 32, no joint is formed, but these merge into one another in one piece. Likewise, the connection of the support member 22 may be performed on the base member 27 and the beam member 14 without joint.

The special shape of the support member 22 with two opposing, oblique inclined portions 31 and 32, in which the actuator 24 engages transversely to the adjustment direction 21 in the middle of the support member 22 offers special advantages, since this embodiment of a support member 22 no horizontal relative displacement between the beam element 14 and the base member 27 causes, but only in the upper pivot point a lowering or lifting. In the area of small helix angles, for example below 30 °, this embodiment of a support element 22 also brings about a certain toggle effect, as a result of which large actuating forces can be exerted on the beam element 14 with relatively small actuating forces of the actuator 24. This effect can also be achieved if no separate joints 33 are provided or these are arranged only at certain points of the support element 22.

It is advantageous if the two inclined sections 31 and 32 have identical but opposing helix angles 23 and the two inclined sections 31 and 32 have identical lengths, that are substantially symmetrical with respect to a plane perpendicular to the adjustment direction 21 symmetry plane 34 are executed. The actuator 24 is in Fig. 4 simplified represented by an arrow, which also represents the optimal direction of force introduction, which is also substantially in the plane of symmetry 34 of the support element.

In Fig. 4 For the sake of simplicity, only a single support element 22 of a support structure 19 is shown, however, an arrangement of a plurality of support elements 22 is preferably provided in the various embodiments of a bending press, whereby the forces required or occurring during an adjustment process and a bending operation on several support elements 22nd to distribute. Furthermore, the trajectory 18 of the support surface 9 by the use of multiple support elements 22 is more uniform.

Fig. 5 shows a partial view of another embodiment of a support structure 19 for a beam member 14 which includes a plurality of support members 22 which can be changed by means of an actuator 24 in its helix angle 23, and thereby the beam member 14 in the area above the support members 9 are actively raised or lowered can. The individual support elements 22 are arranged side by side in the longitudinal direction 35 of the beam element 14 below the beam member 14 and have in this embodiment, similar to the embodiment according to Fig. 4 in each case two inclined sections 31 and 32, the with respect to the adjustment direction 21 opposing helix angle 23 and with respect to a plane parallel to the longitudinal direction 35 symmetry plane 34 are arranged and executed substantially symmetrically.

Adjacent support elements 22 in this case have an orientation in the same direction, ie corresponding inclined sections 31 and 32 adjacent support members 22 have in the same direction oriented helix angle 23. These helix angle 23 adjacent support members 22 may be identical, but it is also possible that the helix angle 23 of a support element 22 and the support portions 31 and 32 to the adjacent support member and the adjacent support portions 31 and 32 increases and decreases. As previously described, causes a larger helix angle 23 at the same adjustment of the actuator 24, a greater height adjustment of the beam member 14, as a smaller helix angle 23, whereby different helix angle 23 allow for the same adjustment of the actuator 24 locally different adjustments of the beam element 14 to achieve.

In principle, each support element 23 can be actuated or adjusted by its own actuator 24, such as Fig. 5 However, it is also possible that by means of a single actuator 24 a plurality of juxtaposed support members 22 can be adjusted simultaneously, whereby a small number of actuators 24, a large number of support members 22 can be adjusted.

Adjacent support elements 22 are based in this case in particular in the direction of the introduction of force of the actuator 24 from each other, whereby the adjusting force of the actuator can be introduced into several consecutive support elements 22 at the same time. In Fig. 5 the mutual support of the support elements 22 is realized by webs 36 which connect adjacent support members 22 integrally with each other. It is of course also possible that between the individual support elements 22 separate spacers 37 are arranged, as in Fig. 5 indicated by dashed lines. The support structure 19, which supports the beam element 14 with respect to the stationary remainder of the table 3 or of the press beam 5, forms in the illustrated embodiment a herringbone structure 38 which makes it possible, by means of a single actuator 24, for a section or a large part of a beam element 14 to support very stable and at the same time be able to adjust the support surface 9 between a flat and a curved course.

The individual support elements 22 can be similar as in Fig. 4 be designed as separate components that connect the beam member 14 with the base member 27, but is also advantageous in Fig. 5 illustrated embodiment in which the herringbone structure 38 is formed by integrally connected support members 22 which is used as a single contiguous component between the base member 27 and beam member 14 or as shown also integrally connected to the base member 27. In Fig. 5 It is further indicated that the herringbone structure 38 can also be integrated into the beam element 14 'in one piece, whereby, for example, the entire table 3 can consist of only one component.

The individual support elements 22 can, as in Fig. 5 represented, are prepared in such a way that in a plate-like base member 27, a sequence of inclined with respect to the adjustment direction 21 slots 39 is introduced, whereby between adjacent slots, the individual support members 22 and support portions 31, 32 are formed. These slots 39 can be made for example by laser cutting with relatively little effort. With the help of programmable laser cutting machines such herringbone structures 38 can also be made very flexible and adapted to the requirements of a bending press 1.

In Fig. 6 a further embodiment of a support structure 19 for a bending press 1 according to the invention is shown; and in Fig. 7 a cross section through a table 3 of a bending press 1 with a support structure 19 according to Fig. 6 ,

The support structure 19 in Fig. 6 has a plurality of support members 22 formed with inclined portions 31 and 32 Stützrauten 40 which support the beam member 14 either directly or, as in Fig. 6 shown, with the interposition of a cross connector 41 can act on the underside of the beam member 14.

In the region of the horizontal plane of symmetry 34 of the support grooves 40, the support grooves 40 are mutually supported in the horizontal direction by means of actuators 24, with which also the respective helix angle 23 of the inclined sections 31, 32 can be adjusted and thus the curvature of the beam element 14 can be influenced. The two outer support rods 40 were supported by further actuators 24 relative to the base element 27 of the table 3. In Fig. 6 however, it is also possible for any number of supportive slits 40 or a single supportive slit 40 to be provided. Due to the symmetry of the support grooves 40 with respect to the symmetry plane 34 parallel to the beam element 14 and symmetrical adjustment of the support elements 22 with respect to the adjustment direction 21, the upper and lower connection points of the support elements 22 are not displaced in the horizontal direction and therefore do not produce appreciable forces in the horizontal direction inter alia, the cross connector 41, as already described with reference to FIG Fig. 5 also form the beam element 14 '.

The operation of this Stützrauten 40 in conjunction with the actuators 24 is similar to that of a scissors jack and can also be based on Fig. 4 described and also in Fig. 5 possible toggle effect can be achieved.

As actuators 24 preferably hydraulic cylinders are used which represent an optimal solution for the low adjustment path required and high adjustment forces.

In support structures in which larger adjustment of the support members 22 are required, the use of spindle drives is possible, in which case preferably a plurality of support members 22 are simultaneously adjusted by a spindle drive, since it would not be economical for each support member 22 to provide its own spindle drive.

In the case of a plurality of actuators 24 acting on the support elements 22 of a support structure 19, it is advantageous if these allow individually adjustable adjustment paths, as this also allows a curve 18 of the beam element 14 adapted to the respective application to be adjusted, which makes possible a deflection 17 of the press beam 5 in the best possible manner compensated. This individual control of the actuators 24 may be of an in Fig. 1 The controller 42, which can also take into account, among other things, measured values of the deflection of the press beam 5 as well as measured values of the active deformation of the beam element 14, and a regulation of the course 18 of the support surface 9 based on measured values of the deflection of the beam Pressbar 5 can generate. The control can alternatively or additionally also be based on force measurements on the press beam 5 or on the beam element 4.

In Fig. 7 is a cross section through a table 3 of a bending press 1 according to the invention shown, wherein a support structure 19 according to Fig. 6 is used. The support structure 19 with the support elements 22 may, as Fig. 7 shows, be performed on both sides of the adjustment plane of the press bar 5 parallel guide plates 43 or aprons with little play, whereby a possible buckling of support members 22 can be avoided transversely to the adjustment of the press bar 5. The guide plates 43 can cause a substantial increase in the rigidity of the beam member 14 so that no local deformations of the beam element occur at punctual loads by bending operations with short bending edges.

Fig. 7 shows in dashed lines nor the variant that the beam member 14 is connected to increase the rigidity with the guide plates 43. The guide plates 43 may further be connected to one another at their spaced from the beam member 14 end portions 44 by means of a lower chord 45 with each other, whereby the basic stiffness of the beam member can be further increased. The same effect as a separate lower flange 45 can also cause a fixation at the lower end of the base member 27.

In Fig. 8 is simplified, a further embodiment of a support structure 19 is shown, with which a support surface 9 of a beam member 14 can be adjusted starting from a flat initial state in a convex or concave curved course 18. The support structure in this case comprises a plurality of support elements 22, which are arranged symmetrically to a median plane 26 of the bending press and on both sides of the median plane 26 in the same direction oriented helix angle 23 have. The upper ends of the oblique support members 22 of a half are combined by means of a cross connector 41 and presses it on the underside of the beam member 14 when the actuators 24 which act in this embodiment on the cross connector 41 are activated. To compensate for the inevitably arising horizontal movement component of the cross connector 41 is between the cross connectors 41 and the underside of the beam member 14 is a displacement bearing. 30 provided, whereby no or no significant horizontal forces are transmitted between the cross connectors 41 and the beam member 14. The sliding support 30 is preferred formed by a sliding bearing, which is inexpensive to manufacture and has lower surface pressures than, for example, a rolling bearing.

Fig. 9 shows a further embodiment of a support structure 19, which on both sides of the median plane 26 comprises a herringbone structure 38, which can be adjusted by means of lateral actuators 24 which are arranged in the region of the plane of symmetry 34 of the herringbone structures 38. By lateral pressure forces of the actuators 24, the central portion 28 of the beam member relative to the end portions 29 are raised, thereby to allow optimum adaptation of the support surface 9 to a deflection 17 of the press beam 5. The herringbone structures 38 according to Fig. 9 essentially correspond to those of the embodiments of Fig. 5 or 6 , Since all support elements 22 are adjusted horizontally by the actuators 24 in the region of the plane of symmetry 34, and in the central region 28, the beam member 14, however, must be raised more, the support elements 22 are arranged in the central portion 28 with a larger helix angle 23 than the outer and the end portions 29 adjacent support members 22, which have a smaller helix angle 23 '.

The embodiments show possible embodiments of the bending press, it being noted at this point that the invention is not limited to the specifically illustrated embodiments thereof,

In the various figures, several embodiments of the bending press are shown, wherein in the figures for the same parts the same reference numerals or component designations are used throughout. In order to avoid unnecessary repetitions of the component descriptions, reference is made to the descriptions in the above-described figures.

For the sake of order, it should finally be pointed out that in order to better understand the structure of the bending press, these or their components have been shown partially unevenly and / or enlarged and / or reduced in size.

The task underlying the independent inventive solutions can be taken from the description. <B> Reference Numbers </ b> 1 bending press 26 midplane 2 machine frame 27 base element 3 table 28 the central region 4 guide assembly 29 end 5 pressing bars 30 sliding bearings 6 drive means 31 oblique section 7 side cheek 32 oblique section 8th cross-connector 33 joint 9 support surface 34 plane of symmetry 10 support surface 35 longitudinal direction 11 bending tool 36 web 12 bending tool 37 spacer 13 workpiece 38 herringbone 14 beam element 39 slot 15 beam element 40 supporting diamond 16 total area 41 cross-connector 17 deflection 42 control 18 course 43 guide plate 19 support structure 44 end 20 setting device 45 lower chord 21 adjustment 22 support element 23 helix angle 24 actuator 25 longitudinal axis

Claims (15)

1. A bending press (1), comprising a stationary table (3) that is connected to a machine frame (2), a press beam (5) that can be adjusted in the direction to and from the table (3) along guide arrangements (4) on the machine frame (2) with the aid of at least one driving means (6), opposing support surfaces (9, 10) on the table (3) and on the press beam (5) for bending tools (11, 12) and/or tool receptacle devices, and an adjusting device (20) on the table (3) or on the press beam (5) for actively adjusting a support surface (9) between an essentially plane and an arched extent (19), wherein the support surface (9) is formed by a beam element (14) of the table (3) or the press beam (5) that extends over the entire length (16) of the table (3) and/or the press beam (5) and is supported by means of a support structure (19) of the table (3) or the press beam (5), characterized in that the support structure (19) features at least one elongate support element (22) that can at least sectionally assume an angle of inclination (23) relative to the adjustment direction (21) of the press beam (5), and in that the adjusting device (20) comprises an actuator (24) that acts upon the support structure (19), particularly the support element (22), transverse to the adjustment direction (21) and makes it possible to change the angle of inclination (23) of the support element (22) within the table (3) and/or the press beam (5).
2. The bending press (1) according to claim 1, characterized in that the support structure (19) comprises multiple inclined support elements (22).
3. The bending press (1) according to claim 1 or 2, characterized in that the angle of inclination (23) of the at least one inclined support element (22) lies within a plane extending parallel to the adjustment plane of the press beam (5).
4. The bending press (1) according to one of the preceding claims, characterized in that the at least one support element (22) is guided between two guide plates (43) extending parallel to the adjustment plane of the press beam (5).
5. The bending press (1) according to one of the preceding claims, characterized in that a longitudinal dimension of the at least one support element (22) in its supporting direction corresponds to at least triple its cross-sectional dimension in the direction extending parallel to the beam element (14).
6. The bending press (1) according to one of the preceding claims, characterized in that a displacement bearing (30), which is movable in the longitudinal direction of the beam element (14), is arranged between the support element (22) and the beam element (14) or between the support element (22) and the stationary part of the support structure (19).
7. The bending press (1) according to one of the preceding claims, characterized in that the support elements (22) and the actuators (24) are arranged symmetric referred to a center plane (26) of the bending press (1) extending perpendicular to a longitudinal axis of the beam element (14).
8. The bending press (1) according to one of the preceding claims, characterized in that multiple adjacent support elements (22) are formed by inclined slots (39) produced in a plate-like base element (27) of the table (3) or the press beam (5), wherein the slots (39) extend through the entire base element (27).
9. The bending press (1) according to one of the preceding claims, characterized in that the angles of inclination (23) of support elements (22) arranged in the central section (28) of the beam element (14) are greater than those of support elements (22) arranged closer to the end sections (29).
10. The bending press (1) according to one of the preceding claims, characterized in that the angle of inclination (23) of the support element (22) or the support elements (22) relative to the adjustment direction (21) lies between 0° and 45°.
11. The bending press (1) according to one of the preceding claims, characterized in that the support element (22) or the support elements (22) respectively is or are realized essentially symmetrical referred to a plane of symmetry (34) extending perpendicular to the adjustment direction (21), namely in the form of a fishbone structure (38) with two sections (31, 32) that are oppositely inclined referred to the adjustment direction (21) of the press beam (5), and in that the force application direction of the actuator (24) essentially lies in the plane of symmetry (34) of the support element (22).
12. The bending press (1) according to one of the preceding claims, characterized in that the support structure (19) comprises multiple support diamonds (40) that are formed by support elements (22) with inclined support sections (31, 32), and in that the force application direction of the actuator (24) essentially lies in the plane of symmetry (34) of the support diamonds (40), which extends perpendicular to the adjustment direction (21).
13. The bending press (1) according to one of the preceding claims, characterized in that the at least one support element (22) is mounted on the beam element (14), on the support structure (19), on the table (3) or on the press beam (5) by means of a joint (33) with at least one end.
14. The bending press (1) according to one of the preceding claims, characterized in that the at least one support element (22) is integrally formed on the press beam (14), on the support structure (19), on the table (3) or on the press beam (5) with at least one end.
15. The bending press (1) according to one of the preceding claims, characterized in that multiple actuators (24), which act upon the support element (22) transverse to the adjustment direction (21), are arranged in the support structure (19), wherein said actuators are driven by a control (42) of the bending press (1) and can be activated with different adjustments individually or at least in groups.

Images