Bending press

Abstract

The invention relates to a bending press (1) for bending workpieces, comprising an upper tool (2) and a lower tool (3), a tool holder (4), in which the upper tool (2) is inserted, and a tool holder (5), in which the lower tool (3) is inserted, wherein the upper tool (2) and the lower tool (3) can be fixed in various positions within the respective tool holder (4, 5), a control device (13) for controlling the bending press (1), a sensor device (8), which is connected to the control device (13), and a stop (6) for positioning the workpiece within the bending press (1), wherein the stop (6) can be moved in relation to the tools (2, 3) by means of a drive (9) controlled by the control device (13). The sensor device (8) is designed to detect the position of the upper tool (2) and of the lower tool (3) within the bending press (1) without contact, and the control device (13) is designed to adapt the movement process by means of which the stop (6) is positioned in relation to the tools (2, 3), in dependence on the position of the upper tool (2) and of the lower tool (3) detected by means of the sensor device (8).

Claims

1. A bending press comprising: an upper tool; a first tool holder configured to hold said upper tool; a lower tool; a second tool holder configured to hold said lower tool; a workpiece-positioning stop movably mounted relative to said upper and lower tools; a drive operatively connected to said workpiece-positioning stop to controllably position said workpiece-positioning stop relative to said tools; a sensor configured to detect, respectively for each of said upper and lower tools, at least one respective tool parameter selected from the group of tool parameters consisting of tool position and tool type; and, a controller in operative communication with said drive, said controller being in operative communication with said sensor to receive therefrom, respectively for each of said upper and lower tools, detected respective values of the at least one tool parameter, said controller having electronic circuitry and programmed instructions that control said drive to controllably position said workpiece-positioning stop relative to said upper and lower tools depending on at least one detected respective value of the at least one tool parameter respectively for each of said upper and lower tools.

2. The bending press as claimed in claim 1, wherein: said workpiece-positioning stop is a rear stop movably mounted for movement parallel to a bending line; and, said sensor is disposed in a region of said workpiece-positioning stop.

3. The bending press as claimed in claim 1, wherein: said sensor is disposed on said workpiece-positioning stop, and said workpiece-positioning stop is movably mounted for movement parallel to a bending line.

4. The bending press as claimed in claim 1, wherein: said sensor has a detection range; and, said sensor is movably mounted to attain at least one operational position where its detection range covers said upper tool and covers at least in-part said lower tool.

5. The bending press as claimed in claim 1, wherein: said sensor is a camera.

6. A bending press as claimed in claim 1, further comprising: at least one scale situated on at least one of said upper and lower tools.

7. A bending press as claimed in claim 1, further comprising: at least one position marking situated on at least one of said first and second tool holders.

8. A bending press as claimed in claim 1, further comprising: at least one two-dimensional code situated on at least one of said upper and lower tools, said at least one two-dimensional code yielding to said sensor feedback about tool type and tool dimensions.

9. A process for bending workpieces with a bending press, comprising the steps of: fixing upper and lower tools in respective upper and lower tool holders; detecting with a sensor at least one tool parameter selected from the group of tool parameters consisting of tool position and tool type; automatically controlling the movement of a workpiece-positioning stop relative to the upper and lower tools, based on the at least one tool parameter from the group of tool parameters consisting of tool position and tool type; automatically positioning the workpiece-positioning stop with a drive motor by said step of automatically controlling the movement of a workpiece-positioning stop relative to the upper and lower tools based on the at least one tool parameter from the group of tool parameters consisting of tool position and tool type; and, bending a workpiece by relative movement of the upper and lower tools relative to one another.

10. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the step of: detecting a respective position of at least one of said upper and lower tools relative to its respective tool holder, during said step of detecting with the sensor at least one tool parameter from the group of tool parameters consisting of tool position and tool type.

11. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the step of: electronically calculating the workpiece-positioning stop displacement path parallel to a bending line, during said step of automatically controlling the movement of the workpiece-positioning stop relative to the upper and lower tools based on the at least one tool parameter from the group of tool parameters consisting of tool position and tool type.

12. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the step of: moving the sensor parallel to a bending line.

13. The process for bending workpieces with a bending press as claimed in claim 9, wherein: said step of detecting with the sensor at least one tool parameter selected from the group of tool parameters consisting of tool position and tool type includes, (a) detecting with the sensor at least one tool parameter of the upper tool selected from the group of tool parameters consisting of tool position and tool type and simultaneously, (b) detecting with the sensor at least one tool parameter of the lower tool selected from the group of tool parameters consisting of tool position and tool type.

14. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the step of: automatically detecting a tool position using at least one position indicator selected from the group of position indicators consisting of a scale and a position marking.

15. The process for bending workpieces with a bending press as claimed in claim 9, wherein: said step of detecting with the sensor at least one tool parameter selected from the group of tool parameters consisting of tool position and tool type includes contour recognition of the tool.

16. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the step of: automatically reading at least one two-dimensional code associated with a tool.

17. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the step of: automatically providing a tool misalignment indication when the upper and lower tools are not aligned with one another.

18. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the step of: calibrating the position of the workpiece-positioning stop using an optically-readable position mark.

19. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the steps of: reading a workpiece-attached code; and, controlling the bending of the workpiece based on said step of reading the workpiece-attached code.

20. A process for bending workpieces with a bending press as claimed in claim 9, further comprising the steps of: including a camera at the sensor; and, electronically returning images recorded with the camera to an operator interface.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The appended list of reference labels is part of the disclosure. The figures are described cohesively and comprehensively. The same reference numbers means the same components, reference numbers with different indices indicate components that have the same function or are similar.

(2) In the figures:

(3) FIG. 1 depicts an exemplary bending press from the front;

(4) FIG. 2 depicts the bending press from FIG. 1 in side view;

(5) FIG. 3 depicts the bending press from FIG. 1 from behind;

(6) FIG. 4 depicts a detailed section of a bending press from the front, with upper and lower tool and the stop;

(7) FIG. 5 depicts an upper tool which is fixed in a tool holder;

(8) FIG. 6 depicts two lower tools which are fixed in a tool holder;

(9) FIG. 7 schematically depicts a possible process sequence in the manner of a flow diagram;

(10) FIG. 8 depicts a schematic view of a bending press with control lines and travel paths; and,

(11) FIG. 9 depicts a schematic view of a link of the sensor device to an operator interface of the bending press.

DETAILED DESCRIPTION

(12) FIG. 1 depicts a bending press 1 for bending workpieces including an upper tool 2 (punch) and a lower tool 3 (die), a tool holder 4 in which the upper tool 2 is inserted and a tool holder 5 in which the lower tool 3 is inserted. The length of the tool holders 4, 5 along the Z-axis, that is, parallel to the bending line, is so great that a plurality of upper and lower tools 2, 3 may be inserted and fixed adjacent to one another in the tool holder 4, 5. This case is shown in FIG. 6 where two lower tools 3 sit in the tool holder 5.

(13) The upper tool 2 and the lower tool 3 can be fixed in various positions inside the respective tool holders 4, 5. That is, the tools can be arranged differently relative to the respective tool holder in the direction of the Z-axis.

(14) The bending press 1 has at least one stop 6 for positioning the workpiece 14 (FIG. 2) inside the bending press 1, where the stop 6 can be moved by means of a drive 9 controlled by a control device 13 (shown in FIG. 8) relative to the tools 2, 3. This movability relates in particular to a movability along the Z-axis but a movability in otherin particular perpendicular theretospatial directions is also feasible. The exemplary version from FIG. 1 shows two stops 6 that are movable independently of one another.

(15) As can be seen from the side view of FIG. 2, in the present exemplary version this recognizably comprises a rear stop, that is, a stop that, when viewed from the operator side of the bending press 1, is located behind the tools 2, 3. The stop 6 serves to position the workpiece 14, for example a sheet to be bent, relative to the tools 2, 3. The rear stop is movable parallel to the bending line (along the Z-axis). The sensor device 8 is located on the rear stop and can be moved together with the rear stop parallel to the bending line.

(16) In an alternative version, the sensor device 8 could be moved independently of the rear stop, for example sitting in its own holder. Preferably, however the sensor device is disposed in the region of the rear stop.

(17) In the version shown, the stop 6 includes stop fingers 7 that are additionally movable. Located next to the stop fingers 7 is a sensor device 8 based on a non-contact measurement principle, in particular in the form of a camera. The sensor device 8 is configured for non-contact detection of the position of the upper tool 2 and lower tool 3 inside the bending press 1. The stop 6 can be seen in detail in FIGS. 3 and 4.

(18) In the version described here, the sensor device 8 detects the position of the tools 2, 3 in the direction along the Z-axis, that is, along the bending line. This measurement can be made by detecting the position of a tool 2, 3 relative to the respective tool holder 4, 5 in which the tool 2, 3 is fixed.

(19) FIG. 8 depicts in schematic view the functional relationships in a bending press 1 which also includes a control device 13 for controlling the bending press 1. The control device 13 in particular controls the drive 12 for the upper tool 2 and therefore the actual pressing process. A further control line connects the control device 13 to the drive 9 for the stop 6. The sensor device 8 is also connected to the control device 13.

(20) The control device 13 is now configured to adapt the movement process by which the at least one stop 6 is positioned relative to the tools 2, 3 depending on the position of the upper tool 2 and the lower tool 3 detected by the sensor device 8.

(21) In FIG. 8, two possible positions of upper tool 2 and lower tool 3 are depicted as an example, one of which is indicated by a dashed line. For the first position (continuous line) a travel path z.sub.1 is calculated as a function of the position in order to align the stop 6 in relation to the tools 2, 3. In this case, as shownthe stop 6 need not necessarily come to rest behind the tool but other positions relative to the tool are also feasible according to the bending plan.

(22) For the second position (dashed line) a travel path z.sub.2 is calculated as a function of the position in order to align the stop 6 in relation to the tools. By means of this position the approach coordinates of the stop 6 are adapted to the respective position of the tool, so that a corresponding bending process may be executed according to the bending plan. The adapting or adaptation of the movement process can naturally also relate to the movements of the stop fingers 7.

(23) Alsoas indicated in FIG. 6a plurality of tools can sit in one tool holder whereby a plurality of bending line sections are defined. The bendings associated therewith can be transferred simultaneously or consecutively to the workpiece. In this case, the approach coordinates of the stop 6 are adapted automatically.

(24) The method for bending a workpiece with a bending press 1 can now comprise the following steps which are shown in the flow diagram of FIG. 7:

(25) Step 20: equipping the bending press with at least one upper tool and/or at least one lower tool which is/are fixed within the respective tool holder.

(26) Step 21: detecting the position of the upper tool 2 and/or lower tool 3 which are fixed in the respective tool holders 4, 5 within the bending press 1 by the sensor device 8. For example, the sensor device 8 can be moved parallel to the bending line (i.e. along the Z-axis) before and/or during the step 21.

(27) Step 22: adapting the movement process via which the at least one stop 6 is positioned relative to the tools 2, 3 depending on the position of the upper tool 2 and/or lower tool 3 detected by the sensor device 8. This step may be accomplished, for example, by calculating a travel path z.sub.1, z.sub.2 of the stop 6 parallel to the bending line (i.e. along the Z-axis).

(28) Step 23: positioning the at least one stop 6 according to the adapted movement process by moving the stop 6 via a drive 9 controlled by the control device 13 relative to the tools 2, 3.

(29) Step 24: performing a bending process by relative movement of upper tool 2 and/or lower tool 3.

(30) Step 25: exchanging and/or adding upper and/or lower tools and the fixing thereof in the respective tool holder.

(31) Steps 21 to 25 may then be repeated.

(32) Preferably the position of the upper tool 2 and the position of the lower tool 3 located at the same height are detected simultaneously. To this end, the sensor device 8 can be moved into a position in which the detection range of the sensor device 8 covers both the upper tool 2 and also the lower tool 3 at least partially.

(33) FIGS. 5 and 6 show preferred variants in which a scale 10 is applied to the respective tool holder 4, 5. Alternatively or additionally, a scale could also be applied to the upper tool 2 and/or the lower tool 3.

(34) In this version, the detecting or the detection of the position of the upper tool 2 and/or the lower tool 3 can be made with the aid of a scale 10. To this end, image recordings of the sensor device 8 configured as a camera are evaluated in view of the relative position of the tool in relation to the scale (e.g., by using appropriate image recognition software). As can be seen from FIGS. 5 and 6, the scale division extends parallel to the bending line.

(35) Preferably, the detection of the position of the upper tool 2 and/or the lower tool 3 is made by contour recognition of the tool 2, 3 by employing appropriate image processing programs.

(36) In a preferred variant, a two-dimensional code 11, in particular a data matrix code (comprising an arrangement of black and white rectangles inside a field) is applied to the upper tool 2 and the lower tool 3. The code 11 contains information about the tool 2, 3 used, in particular about type and dimensions of the tool 2, 3.

(37) Advantageously one code 11 each is applied to the front side and to the rear side of a tool 2, 3. Consequently, the tool 2, 3 can also be inserted in a mirror-inverted manner into a tool holders 4, 5 and detected simply by the sensor device 8.

(38) In this version, the code information can also be read out by the sensor device 8. It can subsequently be checked whether a tool complies with predefined specifications or is compatible with the bending plan.

(39) FIG. 9 depicts a version in which the sensor device 8 includes two non-contact sensors with different spatial detection ranges. The sensors here are optical sensors, in particular cameras. The cameras image different regions along the bending line Z (also called Z-axis). The detection ranges of the sensors may overlap in this case.

(40) It can furthermore be seen from FIG. 9 that the bending press includes an operator interface 27 (here in the form of a screen) that is connected to the control device 13 or the sensor device 8. Here, sensor data of the sensor device 8 and/or data derived from the sensor data can be shown on the operator interface 27. These data can be output automatically to the operator interface 27 during operation.

(41) The sensor device 8 may also include only one sensor or camera. In particular, the images or image sequences recorded with the camera can be displayed on the operator interface 27.

(42) In a preferred method, it can be displayed on the operator interface 27 when the position of the upper tool 2 and/or lower tool 3 detected by means of the sensor device 8 is not correct, in particular when the tools 2, 3 are not aligned with one another. As a result of this information, which may already contain correction values, it is possible for the operator to correct the position of the tools 2, 3 in a simple manner.

(43) The invention is not merely restricted to the described exemplary versions and the aspects emphasized therein. On the contrary, a multiplicity of modifications are possible which lie within the framework of technical disclosure and action. It is also possible to achieve further versions by combining the elements and features without departing from the scope of claimed protection.

LIST OF REFERENCE LABELS

(44) 1 Bending press 2 Upper tool 3 Lower tool 4 Tool holder for upper tool 2 5 Tool holder for lower tool 3 6 Stop 7 Stop finger 8 Sensor device 9 Drive for stop 9 10 Scale 11 Code 12 Drive for upper tool 2 13 Control device 14 Workpiece 20-26 Process steps 27 Operator interface Z Bending line