Bending machine, in particular press brake

Abstract

The invention relates to a bending machine, in particular a press brake, with a machine body (10) having two side elements (8, 8') extending in a first direction (x) from an operator side to a rear side of the bending machine (1) facing away from the operator side, and with an upper beam (2) and a lower beam (5) arranged on the operator side of the bending machine (1) and both extending between the side elements (8, 8') in a second direction (y) running perpendicular to the first direction (x), and with an actuator system (9, 9') for moving the upper beam (2) relative to the lower beam (5) and for forming a workpiece between the upper beam (2) and the lower beam (5) by a bending process along a bending line (B) running in the second direction (y).The bending machine is characterized in that each side element (8, 8') is formed by an upper component (801), on which the upper beam (2) is arranged, and a lower component (802), on which the lower beam (5) is arranged, and the upper component (801) and the lower component (802) of a side element (8, 8') are each mechanically connected to one another by a pivot joint (12, 17) in order to enable the upper beam (2) with the upper components (801) to tilt relative to the lower components (802) and the lower beam (2), wherein a locking device (18) is provided for stiffening the side elements (8, 8').

Description

[0001] The invention relates to a bending machine and in particular to a press brake.

[0002] Bending machines are used to form or bend workpieces. For this purpose, a bending machine consists of an upper beam and a lower beam. During the bending process, the workpiece is positioned between the upper and lower beams. The upper beam, with its attached upper tool, is moved toward the lower beam and its attached lower tool pull to exert force on the workpiece. Since considerable forces are generated during the bending process, a bending machine has a massive machine body with considerable dimensions, which makes it difficult to transport.

[0003] Document EP 2 908 961 B1 discloses a bending machine according to the preamble of claim 1. This bending machine includes an upper beam and a lower beam arranged between two side supports. An alignment frame with a concave opening is provided on each side support, with the alignment frame having a sliding means between the upper beam and the upper part of the alignment frame. The alignment frame ensures movement of the bending tools on the upper beam along a predetermined path.

[0004] The document EP 3 208 007 B1 discloses a bending machine on which compensating actuators are provided in order to counteract a deformation of the machine body of the bending machine occurring during the bending process.

[0005] The object of the invention is to create a bending machine which can be transported more easily than conventional bending machines.

[0006] This object is achieved by the bending machine according to claim 1. Further developments of the invention are defined in the dependent claims.

[0007] The bending machine according to the invention, which in a preferred variant is a press brake, includes a machine body having two side elements extending in a first direction from an operator side to a rear side of the bending machine facing away from the operator side. Furthermore, the bending machine includes an upper beam and a lower beam arranged on the operator side of the bending machine, both extending between the side elements in a second direction perpendicular to the first direction. Furthermore, the bending machine includes an actuator for moving the upper beam relative to the lower beam and for forming a workpiece between the upper beam and lower beam by means of a bending process along a bending line extending in the second direction.

[0008] In the bending machine according to the invention, each side element is formed by an upper component, on which the upper beam is arranged, and a lower component, on which the lower beam is arranged. The upper component and the lower component of a side element are each mechanically connected to one another by a pivot joint to enable the upper beam with the upper components to tilt relative to the lower components and the lower beam. A locking device is provided to stiffen the side elements.

[0009] The bending machine according to the invention has the advantage that the dimensions of the bending machine can be changed by tilting the upper beam relative to the lower beam, thus facilitating transport of the bending machine. In particular, this makes it possible to load the bending machines according to the invention as a whole into standard freight containers. Disassembling the bending machines for transport in standard freight containers is no longer necessary. At the same time, the locking device ensures that the side elements can be stiffened, allowing the bending machine to absorb the forces occurring during the bending process.

[0010] The pivot joints provided in the bending machine can be designed in different ways. In particular, a corresponding pivot joint is a device for restricting all degrees of freedom except the pivoting of the upper component relative to the lower component. Preferably, the pivot joints each provide a detachable connection for reversibly separating the upper component and the lower component.

[0011] In a preferred embodiment, the pivot joints each have a pivot pin or a pivot bearing pin, about which the upper component can pivot relative to the lower component. Likewise, the pivot joints can each have a hinge for pivoting the upper component relative to the lower component.

[0012] In a further preferred variant, at least one of the pivot joints on one of the side elements includes one or more connecting components that are rigidly connected to the lower component and to which the upper component is pivotally attached, or that are rigidly connected to the upper component and to which the lower component is pivotally attached. Preferably, the pivot joint on both side elements includes the connecting component(s) described above. With this embodiment, the pivot joint is implemented in a structurally simple manner.

[0013] The above-described rigid connection of the connecting components to the lower component or the upper component is preferably a material connection, in particular a welded connection. The above-described pivotable fastening of the upper component or lower component to the connecting component(s) is preferably achieved via the pivot pin described above.

[0014] In a particularly preferred variant, a pair of connecting components is provided for at least one of the side elements, and preferably for both side elements, wherein the connecting components of the pair are arranged next to one another in the second direction, and wherein a section of both the upper component and the lower component is arranged between the connecting components of the pair. This achieves a very good mechanical connection between the upper component and the lower component.

[0015] In a further preferred variant of the bending machine according to the invention, the locking device for at least one of the side elements, and preferably both side elements, comprises one or more fixing elements each, which are intended to be inserted into the side element to stiffen it and removed from the side element to release the stiffening. This creates a simple and cost-effective design of the locking device. Bolts, pins, screws, or similar elements are advantageously suitable as fixing elements.

[0016] A preferred embodiment of the bending machine according to the invention comprises one or more compensation actuators designed to exert a force on the side elements that counteracts the deformation of the side elements during the bending process. This compensates for the springback of the side elements that occurs during the bending process and negatively affects the bending result.

[0017] Preferably, a compensation actuator is provided for each side element of the bending machine according to the invention. Depending on the configuration, the compensation actuators can comprise, for example, one or more hydraulic actuators, in particular lifting cylinders, and / or one or more electromechanical actuators. Furthermore, a compensation actuator can contain, for example, a wedge device.

[0018] In a further preferred embodiment, the bending machine according to the invention includes a control device configured to control the compensation actuator(s) based on a set of bending parameters for a bending process to be performed and / or based on sensor data from which the deformation of the side elements during the bending process results. The control is carried out in such a way that the force exerted on the side elements compensates for the deformation of the side elements up to a predetermined extent. With this embodiment, the springback of the side elements during the bending process is compensated very precisely and reliably.

[0019] Depending on the embodiment, the above bending parameters can include different variables. The bending parameters can, in particular, include parameters of the workpiece to be bent, such as the workpiece material, and / or parameters relating to the bending tools used.

[0020] The sensor data described above can be acquired in various ways. In particular, the sensor data can represent measurement data from a sensor system that directly measures the deformation of the side elements. It is also possible for the deformation of the side elements to be calculated by the control device from sensor data from a sensor system that does not directly measure the deformation. For example, the deformation can be determined from the hydraulic pressures of the (hydraulic) actuators for moving the upper beam. Another indirect determination of the deformation is possible through the direct measurement of the bending angle, followed by a comparison of the desired bending angle with the target bending angle.

[0021] In a further preferred embodiment, at least one of the side elements, and preferably each side element, has a gap in which at least one of the compensation actuators engages to force the gap apart by applying force, thereby counteracting the deformation of the side elements during the bending process. This achieves a simple and reliable transmission of force from the compensation actuators to the side elements. The compensation actuators can be activated either directly during the bending process or as pre-compensation before the bending process. With pre-compensation, the amount of compensation is determined in advance from known bending data for a bending step.

[0022] In a preferred variant of the embodiment just described, the gap extends from one end of the side element, which is adjacent to the rear of the bending machine, into the side element. This allows the force of the compensation actuators to be transmitted very efficiently into the side elements.

[0023] In a further preferred variant, the intermediate space is formed between the upper component and the lower component, whereby a simple integration of the compensation actuators into the bending machine is achieved.

[0024] Embodiments of the invention are described in detail below with reference to the attached figures.

[0025] They show: Fig. 1 is a perspective view of an embodiment of a bending machine according to the invention in the operating state; Fig. 2 is a side view of the bending machine from Fig. 1 ; Fig. 3 a side view of the bending machine from Fig. 1 in a variant; Fig. 4 a side view of the bending machine from Fig. 1 and 2 in a transport condition in which the upper beam is tilted relative to the lower beam and the bending machine is in an indicated standard freight container for transport; and Fig. 5 a side view of the bending machine from Fig. 3 in a transport condition in which the upper beam is tilted relative to the lower beam and the bending machine is in an indicated standard freight container for transport.

[0026] In Fig. 1 A perspective view of a variant of a bending machine 1 according to the invention is shown. Only components of the bending machine 1 that are essential to the invention are shown. The bending machine 1 is located in Fig. 1 in the operating state in which it is used to bend workpieces.

[0027] In all of the following Figuren 1 bis 3 The corresponding spatial directions are indicated by a Cartesian coordinate system with x-axis, y-axis, and z-axis. The direction of the x-axis corresponds to the direction from the front (operator side) to the rear of the bending machine 1. The direction of the y-axis is the transverse direction of the bending machine 1 and corresponds to the direction of the bending line B (see Fig. 2 ), along which a corresponding workpiece is bent by means of the bending machine 1. The direction of the z-axis is the height direction or vertical direction. The direction of the x-axis corresponds to the first direction within the meaning of claim 1, and the direction of the y-axis corresponds to the second direction within the meaning of claim 1.

[0028] The bending machine 1 comprises a machine body 10 with two side elements 8 and 8', which are offset from one another in the y-direction. The two side elements 8, 8' are shaped such that a bulge 11 is formed in them, arranged adjacent to the operator side. An upper beam 2 and a lower beam 5 extend between the side elements 8 and 8'. An upper tool 4 is located on an upper tool holder 3 of the upper beam 2, and a lower tool 7 is attached to a lower tool holder 6 of the lower beam 5. An actuator 9 is provided on the side element 8, and an actuator 9' is provided on the side element 8'. By means of these actuators 9, 9', the upper beam 2 can be moved along the z-axis relative to the lower beam 5. The upper beam 2 is guided on the side elements 8 and 8' (the guides are not shown). In contrast to the upper beam 2, the lower beam 5 is rigidly connected to the side elements 8 and 8'.

[0029] To perform a bending process, a workpiece, such as a metal sheet, is inserted by a human operator or by a connected automation unit via the front or operator side into the bending machine 1 between the upper tool 4 and the lower tool 7. The upper beam 2 with the upper tool 4 is then moved towards the lower tool 7 by means of the actuators 9, 9', whereby a force is exerted on the workpiece and thereby a bending of the same along the bending line B running in the y-direction.

[0030] The bending machine 1 is characterized in that both side elements 8, 8' each comprise a separate upper component 801 and a separate lower component 802, wherein the upper component 801 can be tilted toward the operator side relative to the lower component 802 if necessary. Tilting the upper components 801 of the side elements 8, 8' results in an upper section of the machine body 10, including the upper beam 2, being folded relative to a lower section of the machine body 10. This allows the bending machine to be placed in a compact transport state, as will be explained in more detail below.

[0031] The lower end of the upper component 801 and the upper end of the lower component 802 are arranged between two connecting components 12. One connecting component 12 is located on the outside of the corresponding side element 8 or 8', and one connecting component 12 is located on the inside of the corresponding side element 8 or 8'. The figures only show the connecting component 12 on the outside of the side element 8 or 8'. The connecting components 12 are integrally connected to the upper section of the lower component 802, for example via a welded connection. In contrast, the lower section of the upper component 801 is connected to the connecting components 12 via a pivot pin 17. The pivot pin 17 is inserted into aligned openings in the connecting components 12 and the upper component 801.

[0032] Furthermore, in the Fig. 1 In the illustrated operating state of the bending machine, the upper component 801 is fixed relative to the lower component 802 by means of a locking device 18, whereby the respective side elements 8, 8' are stiffened. This locking device 18 is realized by means of at least one fixing element, which is inserted into mutually aligned openings 18b (see Fig. 4 ) of the connecting components 12 and the upper component 801. The fixing element is designed as a bolt in the present case, but can also be designed, for example, as a pin, screw, or similar. For transporting the bending machine, the locking device 18 can be released by removing the at least one fixing element from both side elements 8, 8', so that tilting of an upper section of the bending machine 1 is made possible by pivoting the upper components 801 about the respective pivot pins 17.

[0033] Out of Fig. 1 It is also evident that an intermediate space 14 is formed between the upper component 801 and the lower component 802 of the side element 8', adjacent to the rear of the bending machine 1. A compensation actuator 13 is arranged in this intermediate space, which can be designed, for example, as a hydraulic or electromechanical actuator. A corresponding intermediate space 14 with a compensation actuator 13 is also provided in the side element 8. The respective compensation actuators 13 on the two side elements 8 and 8' can counteract the springback of the side elements 8, 8' that occurs during the bending of a workpiece, as will be described in more detail below.

[0034] Fig. 2 shows a side view of the bending machine 1 from Fig. 1 , where the side view shows the structure of the side element 8. The structure of the side element 8 is symmetrical to the structure of the side element 8', which in Fig. 1 is shown. From Fig. 2 The bending line B is visible, which extends in the y-direction. Furthermore, the pivot pin 17 and the locking device 18 in the form of a corresponding fixing pin can be clearly seen. Fig. 2 Also shown schematically is a control device 16 with which the bending machine 1 is controlled. In addition to the actual control of the bending process by actuating the actuators 9, 9', the control device 16 also controls the compensation actuators 13, which are arranged in the corresponding spaces 14. The control device 16 acts on the compensation actuators 13 in such a way that, upon deformation or springback of the side elements 8, 8', which occurs when the upper beam 2 exerts force on the workpiece being bent, the compensation actuators 13 are moved apart in the z-direction, so that the deformation or springback is counteracted and thus reliably ensured very good bending results.

[0035] In the embodiment of the Fig. 2 the control device 16 accesses data from a sensor system (not shown) which measures the deformation of the side elements 8 or 8' during the bending process. The stroke of the compensation actuators 13 is then suitably adjusted according to the magnitude of the deformation so that this deformation is compensated. The control device 16, in combination with the compensation actuators 13 and a corresponding sensor system, thus actively counteracts any springback of the side elements 8, 8'. Nevertheless, it is also possible if necessary to passively counteract the springback. In this case, corresponding bending parameters, such as parameters relating to the workpiece to be bent and / or the upper tool 4 and / or the lower tool 7, are read in by the control device 16. These parameters can, for example, be entered by an operator via a user interface (not shown).Based on the bending parameters, the control device 16 then determines the expected deformation of the side elements. Based on this expected deformation, the compensation actuators 13 are then controlled accordingly to compensate for the deformation.

[0036] Fig. 3 shows a side view of a bending machine 1 in a variant which, compared to the bending machine from Fig. 1 or Fig. 2 The structure of the bending machine 1 from Fig. 3 largely corresponds to the structure of the bending machine from Fig. 2 . In particular, the side elements 8, 8' in turn comprise an upper component 801 and a lower component 802, and a pivot pin 17 and a locking device 18 are provided, so that a tilting of an upper section of the bending machine 1 is enabled by pivoting the upper components 801 about the respective pivot pins 17 when the locking device 18 is released by removing the corresponding fixing element from both side elements 8, 8'. The difference between the embodiment of the Fig. 3 compared to Fig. 2 is that in the bending machine 1 the Fig. 3 no compensation actuators 13 are provided. Accordingly, no gap 14 is formed between the upper component 801 and the lower component 802 of the respective side elements 8, 8'.

[0037] Fig. 4 shows the bending machine Fig. 1 or Fig. 2 in transport condition. The bending machine 1 is located in a standard freight container 19 intended for transport. In contrast to Fig. 1 and Fig. 2 are in the transport condition of the Fig. 3 the upper tool holder 3 with the upper tool 4 and the lower tool holder 6 with the lower tool 7 are removed from the bending machine 1. In the transport state, the upper section of the bending machine 1 is folded down relative to the lower section.

[0038] To switch the bending machine from the operating state of Fig. 1 or Fig. 2 To bring the side elements 8 and 8' into transport state 3, the locking device 18 is released by removing the fixing element on both side elements 8 and 8'. This removes the stiffening of the side elements 8, 8'. Subsequently, the upper components 801 of the side elements 8 and 8' are tilted forward by pivoting about the pivot pins 17. After the upper components 801 have tilted relative to the lower components 802, the fixing element of the locking device 18 can be reinserted into the aligned openings 18b of the connecting components 12. Fig. 4 the fixing element is not in the openings 18b.

[0039] As from Fig. 4 As can be seen, by tilting the upper components 801 relative to the lower components 802, a significant reduction in the height of the bending machine 1 can be achieved, so that it fits into commercially available containers 19 and can therefore be easily transported.

[0040] Fig. 5 shows a view analogous to Fig. 4 , whereby now the variant of the bending machine 1 from Fig. 3 in the transport state in which the upper section of the bending machine 1 is folded down relative to the lower section. Fig. 5 differs from Fig. 4 only in the sense that the bending machine 1 of the Fig. 5 does not contain any compensation actuators in corresponding spaces 14. Therefore, a detailed description of the Fig. 5 and in this regard Fig. 4 referred to.

[0041] The embodiments of the invention described above offer a number of advantages. In particular, the dimensions of the bending machine 1 can be changed by pivoting its upper section, making the bending machine 1 easier to transport. Furthermore, compensation actuators 13 can optionally be easily integrated into the bending machine 1 to counteract springback of the side elements 8, 8' in the operating state of the bending machine 1, in which the side elements 8 and 8' are stiffened by the locking device 18. List of reference symbols:

[0042] 1 Bending machine 2 Upper beam 3 Upper tool holder 4 Upper tool 5 Lower beam 6 Lower tool holder 7 Lower tool 8, 8' Side elements 801 Upper component of the side element 802 Lower component of the side element 9, 9' Actuators 10 Machine body 11 Bulge in the side element 12 Connecting component 13 Compensation actuator 14 Intermediate space 16 Control device 17 Pivot pin 18 Locking device (fixing element) 18b Opening for locking device 19 Freight container B Bending line

Claims

1. Bending machine, in particular a press brake, comprising a machine body (10) having two side elements (8, 8') extending in a first direction (x) from an operator side to a rear side of the bending machine (1) facing away from the operator side, and comprising an upper beam (2) and a lower beam (5) arranged on the operator side of the bending machine (1) and both extending between the side elements (8, 8') in a second direction (y) running perpendicular to the first direction (x), and comprising an actuator system (9, 9') for moving the upper beam (2) relative to the lower beam (5) and for forming a workpiece between the upper beam (2) and the lower beam (5) by a bending process along a bending line (B) running in the second direction (y), characterized in thateach side element (8, 8') is formed by an upper component (801), on which the upper beam (2) is arranged, and a lower component (802), on which the lower beam (5) is arranged, and the upper component (801) and the lower component (802) of a side element (8, 8') are each mechanically connected to one another by a pivot joint (12, 17) in order to enable the upper beam (2) with the upper components (801) to tilt relative to the lower components (802) and the lower beam (2), wherein a locking device (18) is provided for stiffening the side elements (8, 8').

2. Bending machine according to claim 1, characterized in that the pivot joints (12, 17) each have a pivot pin (17) about which the upper component (801) can be pivoted relative to the lower component (802).

3. Bending machine according to claim 1 or 2, characterized in thatat least one of the pivot joints (12, 17) on one of the side elements (8, 8') includes one or more connecting components (12) which are rigidly connected to the lower component (802) and to which the upper component (801) is pivotally attached or which are rigidly connected to the upper component (801) and to which the lower component (802) is pivotally attached.

4. Bending machine according to claim 3, characterized in that the swivel joint (12, 17) on both side elements (8, 8') contains the connecting component(s) (12).

5. Bending machine according to claim 3 or 4, characterized in thata pair of connecting components (12) is provided for at least one of the side elements (8, 8') and preferably both side elements (8, 8'), wherein the connecting components (12) of the pair are arranged next to one another in the second direction (y) and a section of both the upper component (801) and the lower component (802) is arranged between the connecting components (12) of the pair.

6. Bending machine according to one of the preceding claims, characterized in that the locking device (18) for at least one of the side elements (8, 8') and preferably both side elements (8, 8') each comprises one or more fixing elements (18) which are intended to be inserted into the side element (8, 8') to stiffen it and to be removed from the side element (8, 8') to release the stiffening.

7. Bending machine according to one of the preceding claims, characterized in thatthe bending machine (1) comprises one or more compensation actuators (13) which are intended to exert a force on the side elements (8, 8') which counteracts the deformation of the side elements (8, 8') during the bending process.

8. Bending machine according to claim 7, characterized in that the bending machine (1) comprises a control device (16) which is configured to control the compensation actuator(s) (13) based on a set of bending parameters for a bending operation to be carried out and / or based on sensor data from which the deformation of the side elements (8, 8') during the bending operation results, in such a way that the force exerted on the side elements (8, 8') compensates for the deformation of the side elements (8, 8') up to a predetermined extent.

9. Bending machine according to claim 7 or 8, characterized in thatat least one of the side elements (8, 8') and preferably each side element (8, 8') has a gap (14) into which at least one of the compensation actuators (13) engages in order to force the gap (14) apart by the action of force, thereby counteracting the deformation of the side element (8, 8') during the bending process.

10. Bending machine according to claim 9, characterized in that the intermediate space (14) extends from one end of the side element (8, 8') which is adjacent to the rear of the bending machine (1) into the side element (8, 8').

11. Bending machine according to claim 9 or 10, characterized in that the intermediate space (14) is formed between the upper component (801) and the lower component (802).

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