BENDING MACHINE, ESPECIALLY PRESS BRAKE

Description

[0001] The invention relates to a bending machine, and in particular a press brake. Bending machines are used for forming or bending workpieces. For this purpose, a bending machine comprises an upper jaw and a lower jaw. During the bending process, the workpiece is positioned between the upper jaw and the lower jaw, and the upper jaw, with the upper tool attached to it, is moved towards the lower jaw, with the lower tool attached to it, in order to exert force on the workpiece. Since considerable forces occur during the bending process, a bending machine has a massive machine body with considerable dimensions, which makes transporting the bending machine difficult.

[0002] Documents GB 1 159 954 A and CN 116 618 485 A each show a bending machine according to the preamble of claim 1.

[0003] The publication EP 2 908 961 B1 shows a bending machine with an upper jaw and a lower jaw arranged between two side frames. Each side frame has an alignment frame with a concave opening, the alignment frame having a sliding element between the upper jaw and its upper part. The alignment frame ensures that the bending tools move along a predetermined path on the upper jaw.

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

[0005] The object of the invention is to create a bending machine which is easier to transport compared to conventional bending machines.

[0006] This problem is solved 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 embodiment is a press brake, comprises 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 has an upper jaw and a lower jaw, both arranged on the operator side of the bending machine and extending between the side elements in a second direction perpendicular to the first direction. In addition, the bending machine includes an actuator for moving the upper jaw relative to the lower jaw and for forming a workpiece between the upper jaw and lower jaw by means of a bending operation 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, to which the upper jaw is arranged, and a lower component, to which the lower jaw is arranged. The upper and lower components of a side element are each mechanically connected to one another by a pivot joint to allow the upper jaw with the upper components to tilt relative to the lower components and the lower jaw, with a locking device being provided to stiffen the side elements.

[0009] The bending machine according to the invention has the advantage that its dimensions can be changed by tilting the upper jaw relative to the lower jaw, thus facilitating transport. In particular, it makes it possible to place the entire bending machine according to the invention into standard shipping containers. Disassembly of the bending machine for transport in standard shipping containers is no longer necessary. At the same time, the locking device ensures that the side elements can be stiffened so that the bending machine can 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 for pivoting the upper component relative to the lower component. Preferably, the pivot joints each provide a detachable connection for reversibly separating the upper and lower components.

[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 embodiment, 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 element and to which the upper element is pivotably attached, or that are rigidly connected to the upper element and to which the lower element is pivotably attached. Preferably, the pivot joint on both side elements includes the connecting component(s) described above. This embodiment provides a structurally simple way to implement the pivot joint.

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

[0014] In a particularly preferred embodiment, a pair of connecting elements is provided for at least one of the side elements, and preferably for both side elements. The connecting elements of the pair are arranged side by side in the second direction, and a section of both the upper and lower elements is arranged between the connecting elements of the pair. This results in a very good mechanical connection between the upper and lower elements.

[0015] In a further preferred embodiment 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, which are designed to be inserted into the side element to stiffen it and to be removed from the side element to release the stiffening. This results in a simple and cost-effective design of the locking device. Advantageously suitable fixing elements include, for example, bolts, pins, screws, or similar components.

[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. In this way, the springback of the side elements occurring during the bending process, which negatively affects the bending result, is compensated.

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

[0018] In a further preferred embodiment, the bending machine according to the invention includes a control unit configured to control the compensation actuator(s) based on a set of bending parameters for a bending operation to be performed and / or based on sensor data from which the deformation of the side elements during the bending operation results. The control is such 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 operation is compensated very precisely and reliably.

[0019] Depending on the specific design, the bending parameters mentioned above can vary. In particular, the bending parameters can 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 unit from sensor data from a sensor system that does not directly measure deformation. For example, the deformation can be determined from the hydraulic pressures of the (hydraulic) actuators used to move the upper jaw. Another indirect method for determining the deformation is through the direct measurement of the bending angle, followed by a comparison of the target bending angle with the actual 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, thereby counteracting the deformation of the side elements during the bending process. This achieves a simple and reliable force transmission from the compensation actuators to the side elements. The activation of the compensation actuators can occur either directly during the bending process or as pre-compensation prior to the bending process. In the case of pre-compensation, the magnitude of the compensation is determined in advance from known bending data for a given bending step.

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

[0023] In another preferred variant, the space between the upper component and the lower component is formed, thereby enabling simple integration of the compensation actuators into the bending machine.

[0024] Exemplary embodiments of the invention are described in detail below with reference to the accompanying figures.

[0025] They show: Fig. 1 a perspective view of an embodiment of a bending machine according to the invention in its operating state; Fig. 2 a side view of the bending machine made of Fig. 1 Fig. 3 shows a side view of the bending machine. Fig. 1 in one variant; Fig. 4 a side view of the bending machine made of Fig. 1 and 2 in a transport state in which the upper jaw is tilted relative to the lower jaw and the bending machine is located in an indicated standard shipping container for transport; and Fig. 5 a side view of the bending machine made of Fig. 3 in a transport state in which the upper jaw is tilted relative to the lower jaw and the bending machine is in a standard shipping container for transport.

[0026] In Fig. 1 A perspective view shows a variant of a bending machine 1 according to the invention. Only components of the bending machine 1 that are essential for 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 the following described 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 back of bending machine 1. The direction of the y-axis is the transverse direction of 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 vertical direction. The direction of the x-axis corresponds to the first direction in the sense of claim 1 and the direction of the y-axis corresponds to the second direction in the sense of claim 1.

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

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

[0030] The bending machine 1 is characterized by the fact that both side elements 8, 8' each comprise a separate upper component 801 and a separate lower component 802, whereby the upper component 801 can be tilted relative to the lower component 802 towards the operator's side if required. Tilting the upper components 801 of the side elements 8, 8' causes an upper section of the machine body 10, including the upper jaw 2, to fold down relative to a lower section of the machine body 10. This allows the bending machine to be folded into 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 the other connecting component 12 is located on the inside of the corresponding side element 8 or 8'. Only the connecting component 12 on the outside of the side element 8 or 8' is visible in the figures. The connecting components 12 are materially bonded to the upper section of the lower component 802, for example, by means of a weld. In contrast, the connection of the lower section of the upper component 801 to the connecting components 12 is achieved 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 depicted 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, thereby stiffening the respective side elements 8, 8'. This locking device 18 is implemented using at least one fixing element that engages in 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 this case, but could also be, for example, a pin, screw, or similar. For transporting the bending machine, the locking device 18 can be released by removing at least one fixing element from both side elements 8, 8', so that an upper section of the bending machine 1 can be tilted by pivoting the upper components 801 about the respective pivot bolts 17.

[0033] Out of Fig. 1 It is further evident that a gap 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 gap, which can be designed, for example, as a hydraulic or electromechanical actuator. A corresponding gap 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' counteract the springback of the side elements 8 and 8' that occurs during the bending of a workpiece, as described in more detail below.

[0034] Fig. 2 shows a side view of bending machine 1 from Fig. 1 , where the side view shows the structure of page element 8. The structure of page element 8 is symmetrical to the structure of page element 8', which is shown in Fig. 1 shown. From Fig. 2 The bending line B, which extends in the y-direction, is clearly visible. Furthermore, the pivot bolt 17 and the locking device 18, in the form of a corresponding fixing bolt, are clearly recognizable. Fig. 2 A control device 16, which controls the bending machine 1, is also shown schematically. In addition to controlling 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, in the event of deformation or springing of the side elements 8, 8', which occurs when the upper jaw 2 exerts force on the workpiece being bent, the compensation actuators 13 are moved apart in the z-direction, thus counteracting the deformation or springing and reliably ensuring very good bending results.

[0035] In the embodiment of the Fig. 2 The control unit 16 accesses data from a sensor (not shown) that measures the deformation of the side elements 8 and 8' during the bending process. Depending on the magnitude of the deformation, the stroke of the compensation actuators 13 is then adjusted accordingly to compensate for this deformation. Thus, the control unit 16, in combination with the compensation actuators 13 and the corresponding sensor, actively counteracts any springback of the side elements 8 and 8'. However, it is also possible to counteract the springback passively. In this case, the control unit 16 reads in relevant bending parameters, such as parameters relating to the workpiece to be bent and / or the upper tool 4 and / or the lower tool 7. These parameters can be entered by an operator, for example, via a user interface (not shown).Based on the bending parameters, the control unit 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 that differs from the bending machine made of Fig. 1 or Fig. 2 It has been modified. The construction of bending machine 1 from Fig. 3 largely corresponds to the design of the bending machine from Fig. 2 In particular, the side elements 8, 8' each comprise an upper component 801 and a lower component 802, and a pivot pin 17 and a locking device 18 are provided, 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 when the locking device 18 is released by removing the corresponding fixing element from both side elements 8, 8'. The difference in the embodiment of Fig. 3 compared to Fig. 2 consists of the fact that in bending machine 1 of the Fig. 3 No compensation actuators 13 are provided. Consequently, 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 designed for transport. In contrast to Fig. 1 and Fig. 2 are in the transport state of 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 remove the bending machine from the operating state of Fig. 1 or Fig. 2 To bring the assembly into transport state 3, the locking device 18 is released by removing the fixing element from both side elements 8 and 8'. This removes the stiffening of the side elements 8 and 8'. Subsequently, the upper components 801 of the side elements 8 and 8' are tilted forward by pivoting them about the hinge 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 located in 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 standard containers 19 and can therefore be easily transported.

[0040] Fig. 5 shows a view analogous to Fig. 4 , where now the variant of the bending machine 1 from Fig. 3 is shown 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 merely insofar as the bending machine 1 of the Fig. 5 does not contain any compensation actuators in the corresponding intervals 14. Therefore, a detailed description of the Fig. 5 waived and in this regard to Fig. 4 referred.

[0041] The embodiments of the invention described above offer a number of advantages. In particular, the dimensions of the bending machine 1 can be modified by pivoting its upper section, thus facilitating its transport. Furthermore, compensating actuators 13 can optionally be easily integrated into the bending machine 1 to counteract any springing of the side elements 8 and 8' when the bending machine 1 is in its operating state, in which the side elements 8 and 8' are stiffened by means of the locking device 18. Reference symbol list:

[0042] 1 Bending machine 2 Upper jaw 3 Upper tool holder 4 Upper tool 5 Lower jaw 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 Compensating actuator 14 Gap 16 Control device 17 Swivel bolt 18 Locking device (Fixing element) 18b Opening for locking device 19 Freight container B Bending line

Claims

1. A bending machine, in particular a press brake, having a machine body (10) which has 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 having an upper beam (2) and a lower beam (5) which are arranged on the operator side of the bending machine (1) and both extend between the side elements (8, 8') in a second direction (y) that runs perpendicular to the first direction (x), and having an actuator (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 operation along a bending line (B) which runs in the second direction (y), wherein 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 each other by a pivot joint (12, 17) to allow the upper beam (2) with the upper components (801) to tilt relative to the lower components (802) and the lower beam (2), characterised in that a locking device (18) is provided for stiffening the side elements (8, 8').

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

3. The bending machine according to claim 1 or 2, characterised in that at 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 pivotably attached, or which are rigidly connected to the upper component (801) and to which the lower component (802) is pivotably attached.

4. The bending machine according to claim 3, characterised in that the pivot joint (12, 17) includes the connecting component(s) (12) on both side elements (8, 8').

5. The bending machine according to claim 3 or 4, characterised in that for at least one of the side elements (8, 8') and preferably both side elements (8, 8') a pair of connecting components (12) is provided, wherein the connecting components (12) of the pair are arranged next to each other 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. The bending machine according to any one of the preceding claims, characterised in that the locking device (18) for at least one of the side elements (8, 8') and preferably both side elements (8, 8') comprises in each case one or more fixing elements (18), which are provided 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. The bending machine according to any one of the preceding claims, characterised in that the bending machine (1) comprises one or more compensation actuators (13), which are provided to exert a force on the side elements (8, 8'), which counteracts the deformation of the side elements (8, 8') during the bending operation.

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

9. The bending machine according to claim 7 or 8, characterised in that at least one of the side elements (8, 8') and preferably each side element (8, 8') has a gap (14) in each case into which at least one of the compensation actuators (13) engages in order to push the gap (14) apart by applying force, thereby counteracting the deformation of the side element (8, 8') during the bending operation.

10. The bending machine according to claim 9, characterised in that the gap (14) extends from an end of the side element (8, 8') adjacent to the rear side of the bending machine (1) into the side element (8, 8').

11. The bending machine according to claim 9 or 10, characterised in that the gap (14) is formed between the upper component (801) and the lower component (802).