EP3030359B1 - Bending press - Google Patents

Description

The invention relates to a bending press according to the preamble of claim 1 and a method for bending a workpiece with a bending press according to claim 6.

The tool selection and arrangement in bending presses, also called press brakes or bending machines, is done to a high degree manually and only partially supported by the machine control. For this purpose, a bending plan is created, which calculates the product-specific upper and lower tools as well as their theoretical position. However, there is no monitoring of whether or not these tools are actually being used in the machine. In addition, the tools can be placed in positions that do not correspond to the process and have a potential risk.

However, the exact positioning of the tools is necessary in order to carry out bending sequences in high quality and to align the backgauge fingers or a robot accordingly. Appropriate positioning is only possible through precise and labor-intensive measurement by hand and transfer to the machine control.

Inaccurate positioning, disregarding the bending plan or an incorrect number of tools can damage the machine and the periphery. This is also possible due to an incorrect selection of the tool geometry. Furthermore, upper and lower tools with maximum loads are defined - here too, improper handling can result in damage. Damage to press brakes and tools caused by incorrect assembly can also lead to claims of any kind against the manufacturer. Devices are already known which attempt to solve the aforementioned problems in parts, but have a number of disadvantages. So z. B. a display device on the machine only specify a target position, but not its control and detection.

JPH0952124A discloses a bending machine with upper and lower tools, a stop and a barcode reader which is arranged on the stop. The upper and lower tools are each provided with a barcode on the back, which can be read by the barcode reader. The barcode contains information about the nature of the tool. This information are transferred to an NC control. In addition to the barcode reader, a touch sensor or limit switch is provided on the stop with which the dimensions of the respective tool can be determined. Such a procedure is complex and time-consuming since the touch sensor has to be moved directly to the tool several times and in different positions.

With such a system e.g. Tools on the outside of the machine are not recognized, since due to the mechanics no (back) stop can move. In addition, only individually positioned tools can be recognized. Several tools pushed together (or lined up) on a tool holder cannot be distinguished, since the center tools cannot be recognized as such by the known system. In particular, individually positioned tools can only be recognized if the distances between the tools are large enough to be able to move with the backgauge or the fingers in between. A barcode requires a relatively large amount of space, so that it cannot be displayed on very small stamps (upper tool), matrices (lower tool). In addition, the detection of the bar code on inclined surfaces of the tool is very faulty, so that not all tools can be reliably recognized. Also, specially shaped tools cannot be recognized if the backgauge cannot be moved mechanically between the tools. If no approximate position of the tool is known before the acquisition process, there is a high risk of collision with the backgauge. Since the workpieces to be machined also hit the backgauge during positioning, the touch sensors are heavily used and are easily damaged.

The WO2012 / 103565A1 discloses a method for loading a bending press with a bending tool. A controlled handling device with a gripper is used for the bending tool. A control device generates control commands in order to move the tool from an ACTUAL position to a TARGET position when it is introduced into the tool holder. Only when the tool has reached the TARGET position is it inserted into the tool holder and fixed there. The tools held by the handling device must be approached directly from the (back) stop in order to determine their actual position. The process is complex and is based on the basic principle that the tools have to take an exact position within the tool holder so that the desired bending plan can be carried out.

The EP0919300B1 (or. DE69736112T2 ) discloses a bending machine in which the upper tools are provided with bar codes. On the tool clamp for the upper tools, a guide for a scanner for reading the bar codes is provided in the Z direction on the side facing the operator. Furthermore, a linear scale, for example a magnetic scale, is arranged as a position detection device on this tool clamp on the side facing the operator. The position data of the upper tools captured by the scanner are saved and made available again later in a display. In order to manufacture the same product again, the operator has to position the tools by hand based on the stored data exactly according to the stored position. This bending machine is also based on the basic principle that the tools have to take an exact position within the tool holder so that the desired bending plan can be carried out. However, the exact positioning and adjustment of the tool position requires a lot of time and personnel.

The EP1517761B1 and the DE602005005385T2 refer to special tools and tool holders, which can detect tool positions relatively imprecisely via sensors. It is sometimes not possible to classify tools qualitatively and geometrically. Another disadvantage is the high cost of the necessary peripherals, the maintenance intensity, the need to purchase new punches and dies and their restricted geometry. Due to the sensor technology incorporated in the machine and tool, limited pressing forces can still be expected. In addition, movable sensors on the upper and lower beams, as well as the necessary data and supply cables, reduce the variability of a press brake. The number of possible bent parts is restricted.

The EP1510267B1 (or. DE69736962T2 ) discloses a method for displaying a tool arrangement in a press brake. Based on a displayed diagram, it is determined whether the planned bending process is also possible. Subsequently, further tools for certain bend line sections are added and the process is repeated with the new constellation. Just like the previous methods, this method requires exact positioning of the tools in the tool holder.

The DE3830488A1 discloses an electronic tool detection system for press brakes. With this system, it is possible with the help of an electronic control to recognize the built-in tool geometry, to protect the tools against overloading and to keep the operator safe.

The DE4442381A1 relates to a device for position and shape detection of upper cheek tools on folding machines and press brakes. Behind the top beam there is a motor-driven slide in a guide on which a holder for a laser light barrier is mounted. With this, the length of the built-in upper beam tools and their gaps are determined. The values are represented numerically and graphically. In addition, there is a read / write head in the holder, which reads the codes on the back of the upper beam tools.

All known systems relate to reading codes and / or recording the tool dimensions. The exact positioning of the tools within the tool holder plays an important role. In the prior art it is therefore necessary to position the tools exactly in relation to the tool holder, which has the disadvantage of complex and time-consuming assembly of the bending machine.

The object of the present invention is therefore to eliminate the disadvantages of known solutions and to provide a bending press in which an exact positioning of the upper tool and lower tool is no longer necessary. Nevertheless, the entire bending process, including the positioning of the workpiece relative to the tools, should be reliable and deliver bent parts exactly according to the bending plan.

This object is solved by the features of the independent claims.

According to the invention, the sensor device is designed for contactless detection of the position or the position and type of the upper tool and the lower tool within the bending press and the control device is designed to, depending on the position or position and type of the upper tool and the lower tool detected by the sensor device Movement process with which the at least one stop is positioned relative to the tools to adapt.

An important advantage of the invention is that the tools no longer have to be positioned exactly within the tool holder when loading the bending press. This can save time and manpower. The invention is based on the principle that the tools (or their position within the tool holder) are not adapted to the bending plan, but that the movement processes of the at least one stop at the position of the upper and lower tools within the bending press or within the respective one Tool holder can be adjusted. This creates a highly flexible system that automatically regulates the movement processes of the stop required before and during the bending process.

First, the position of the tool already inserted in the tool holder relative to (or in the) tool holder is recorded. Depending on this relative tool position, the movement processes with which the stop (s) (e.g. back stops) are / are then automatically adjusted. A 'non-exact' insertion of the tool into the tool holder or an insertion at a completely different location is thereby automatically 'compensated' or taken into account. In fact, according to the present invention, there is no 'incorrect' insertion or positioning. Any position of the upper and lower tool in the tool holder leads to an automatic adjustment of the stop control and to a correct bending result. For this purpose, a bending program is stored in the control device, which takes into account the position data of the upper and lower tool detected by the sensor device as an input variable and, depending on this input variable, generates control commands for the drive of the stop as an output variable.

"Movement process of the stop" or "method of the stop" is understood to mean any conceivable movement of the stop, in particular also its stop elements such as stop fingers and the like.

With the contactless sensor device, in particular in the form of a camera, it would also be possible to detect a plurality of tools distributed along the Z axis and inserted in the tool holder. An automatic determination of the gap width between two adjacent upper or lower tools would also be conceivable. If the detection area of the sensor device is large enough, all tools can be held in a single receptacle. With smaller ones The camera can be moved so that the individual tools are captured one after the other along the Z axis.

In one embodiment of the invention, the detection of the tool data by means of the sensor device can initially take place independently of the position or at all of the presence of a (back) stop. A stop could therefore only be installed or used after the step of detection. In a further embodiment, other or additional tool data could also be recorded, which are not used to correct the stop, but are used for other purposes.

The at least one stop for positioning the workpiece is preferably a back stop, which can be moved parallel to the bending line, and the sensor device is arranged in the region of the back stop. At this point, the detection area of the sensor device is not disturbed by operating personnel and workpieces to be inserted. This arrangement of the sensor device also does not restrict the working range of the bending press. The sensor is also well protected and, due to its arrangement, can provide reliable images of the back of the tools.

The sensor device is preferably on the stop, e.g. on the backgauge, arranged and, together with the stop, preferably movable parallel to the bending line. The travel axis of the stop, e.g. Back gauge, is used in two ways. In addition, other directions of movement of the stop can also be controlled according to the invention (adapted to the position of the tools). The (back) stop could e.g. be movable in three different spatial directions.

The arrangement of the sensor device, in particular in the form of a reading head or a camera, on the guide of the backgauge or directly on it offers the following advantages: simple arrangement; no additional interference contours on the outside of the machine; no hindrance to the bending process or personnel; the exterior appearance of the machine does not change for the user; the sensor device can be easily retrofitted and also allows the upper tool (punch) and lower tool (die) to be read simultaneously; the sensor device is protected from contamination; several tools along the Z axis can be recognized at the same time; and the Sensor device can be positioned as required. In addition, the position of the tools could also be calculated from the reference position of the backgauge along the Z axis.

The sensor device can preferably be moved into a position in which the detection area of the sensor device at least partially includes both the upper tool and the lower tool. As a result, all the necessary data can be acquired by means of a measurement process or a single image acquisition. Due to the large detection area, only one sensor device is required.

In a further embodiment, the sensor device comprises at least two non-contact, in particular optical sensors with different spatial detection areas. The method of a sensor, e.g. along the bending line, can be omitted. The detection areas of the sensors can overlap.

In a preferred embodiment, the bending press comprises an operator interface, in particular in the form of a screen, sensor data from the sensor device and / or data derived from the sensor data can be displayed on the operator interface (or automatically output on the operator interface during operation). It is preferred if the sensor device comprises at least one camera and the images or image sequences recorded by the camera are displayed on the screen for the operator.

The sensor device is preferably a camera, particularly preferably a matrix camera. This means that not only codes or scales can be recorded, but - especially if they are missing - the tool itself and its contours. A large amount of different information can therefore be acquired with a single measurement / image recording.

A scale or a position marker is preferably applied to the upper tool and / or the lower tool and / or the respective tool holder. This enables a reliable and exact determination of the relative position from tool to tool holder.

A two-dimensional code, in particular a data matrix code, is preferably applied to the upper tool and / or the lower tool, the code preferably containing information about the tool used, in particular about the type and dimensions of the tool. Data matrix codes have several advantages for this application, for example they allow the codes to be read at an angle. As a result, codes from upper tools and lower tools can be evaluated at the same time, provided the camera has a correspondingly large reading window. It is also possible to affix the code on sloping surfaces. Furthermore, this type of coding allows a relatively large error tolerance, i. H. if damaged, the code is still recognized. As already mentioned, even the smallest code dimensions can be read from a relatively large distance. A code is advantageously applied to the front and the back of the tools in order to enable the corresponding tool to be detected even when the tool is rotated (mirrored insertion).

• Erfassen der Position oder der Position und Art des Oberwerkzeuges und/oder Unterwerkzeuges, die in den jeweiligen Werkzeughaltern fixiert sind, innerhalb der Biegepresse mittels der Sensoreinrichtung,
• Anpassen des Bewegungsvorganges, mit dem der zumindest eine Anschlag relativ zu den Werkzeugen positioniert wird, in Abhängigkeit der mit der Sensoreinrichtung erfassten Position oder Position und Art des Oberwerkzeuges und/oder Unterwerkzeuges,
• Positionieren des zumindest einen Anschlages entsprechend dem angepassten Bewegungsvorgang durch Verstellen (Verfahren bzw. Positionieren) des Anschlages mittels eines durch die Steuereinrichtung angesteuerten Antriebes relativ zu den Werkzeugen,
• Durchführen eines Biegevorganges durch relatives Verfahren von Oberwerkzeug und/oder Unterwerkzeug.

The object is also achieved with a method for bending a workpiece with a bending press according to one of the preceding embodiments. This procedure includes the steps:

• Detecting the position or the position and type of the upper tool and / or lower tool, which are fixed in the respective tool holders, within the bending press by means of the sensor device,
• Adapting the movement process with which the at least one stop is positioned relative to the tools, as a function of the position or position and type of the upper tool and / or lower tool detected by the sensor device,
• Positioning the at least one stop in accordance with the adapted movement process by adjusting (moving or positioning) the stop by means of a drive controlled by the control device relative to the tools,
• Carrying out a bending process by relative movement of the upper tool and / or lower tool.

It is a flexible system that, regardless of the position of the tools used, the execution of a specific bending plan enables. By adapting the controlled movement processes of the stop, the system is flexibly adjusted to every tool position.

During the step of detecting the position of the upper tool and / or lower tool, its position relative to the respective tool holder in which the tool is fixed is preferably recorded. This is a particularly reliable method because the spatial proximity of the tool and tool holder means that they can be easily captured and recorded in one holder.

A travel path of the stop parallel to the bending line is preferably calculated during the step of adapting the movement process. The stop is, so to speak, 'tracked' the tool. The traversing path is the output variable here, while the position data of the tools represent the input variable of the bending program.

Before and / or during the step of detecting the position or the position and type of the upper tool and / or lower tool, the sensor device is preferably moved parallel to the bending line. As a result, tools can be positionally recorded along the entire length of the bending press.

The position or position and type of the upper tool and the position or position and type of the lower tool are preferably recorded simultaneously. For this purpose, the detection range of the sensor device includes both the upper tool and the lower tool or, if appropriate, also their tool holder.

The position of the upper tool and / or lower tool is preferably detected using a scale or position marker applied to the upper tool and / or the lower tool and / or the respective tool holder. This increases the accuracy of the position detection. The size and shape of the tools can also be recognized in relation to the scale or at a distance from the camera.

The position or position and type of the upper tool and / or lower tool is preferably detected by a contour detection of the tool. The position of the tool, for example in relation to the (known) position of the sensor device, can be determined here independently of aids such as scales or codes. The camera is able to trace the contours of the tools used recognize and compare with (eg in the control device) stored data. If no data is stored or there is no code at all, the tools are identified based on their geometry and assigned accordingly.

The method preferably comprises a step of reading out information from a two-dimensional code applied to the upper tool and / or the lower tool, in particular a data matrix code. The use of a data matrix code also enables the marking of extremely narrow tools.

The present invention also enables the simultaneous recognition of several codes. The distance to the tools can be changed by connecting the camera to the backgauge. Depending on the resolution of the camera, several codes and contours can be recognized at the same time.

The present idea is based on the fact that the tools used are recognized in their position (optionally also in their type). The parameters determined from this are used via the machine control in such a way that the periphery of the machine is adapted to the bending process at hand. Here is z. B. to call the backgauge, it is then positioned in relation to the tools.

This saves both the measurement and the control between an actual value and a target value - the tools can be inserted at any point and the bending process can be started easily. Among other things, it is no longer necessary to achieve exactly the same tool and workpiece positions for a recurring bent part. As mentioned, it doesn't matter where the tools are. By recognizing and converting to the product, all relevant machine parts (stops) are positioned accordingly and a collision during the bending process is excluded at the same time.

In a preferred embodiment, the upper tool (punch) and lower tool (dies) are recognized simultaneously. The position of these tools relative to one another can be safety-relevant and important for the quality of the bend. In this case, safety-relevant means that an incorrectly positioned upper tool can lead to a collision. Thus, in addition a control corresponding to the bending process is carried out between the upper and lower tools. This prevents incorrect assembly.

In one embodiment, the invention also relates to the determination of the type of tool and the tool position of all upper tools (bending dies) and all lower tools (dies) within a bending press or bending machine.

2D codes (preferably data matrix codes) and a reading head should be used to determine the type of tool (including all its descriptive parameters) and the exact Z-direction position in the bending press. For this purpose, the reading head, preferably a matrix camera, is attached to a Z axis of the back stop of the bending press, as a result of which it is automatically adjustable. Due to the relatively small dimensions of this camera and an existing cable chain on the axis, both installation and data transmission can be easily implemented.

A specific data matrix code is applied to each tool to describe the parameters. This code stores, for example, a simple number, which can be assigned in the database with the necessary parameters of the tool. These include, for example: geometry, maximum load, material, number of bending cycles that have already been carried out, wear, etc. By means of a description using simple numbers, the data matrix codes can also be produced in the smallest version and thus enable application to extremely narrow tools ( Stamps and dies).

A possible process could look like this. After inserting the tools in the bending press, the upper tool (punch) and lower tool (dies) are clamped and are now fixed in their position. The (matrix) camera then moves with the Z axis over the entire length of the bending press. Depending on the reading speed of the camera, images of the tools are generated and evaluated via the machine control and database. The detection of the position of the tools used enables or simplifies a simple scale - attached to the tool clamp of the machine - preferably directly at or at the same height of the data matrix code. The scale is then part of the generated image and thus allows a precise position determination.

• komplette Kontrolle der eingesetzten Werkzeuge
• der Biegeplan kann automatisch auf reale Werkzeugpositionen umgerechnet werden
• deutlich geringere Standzeiten der Biegepresse bei einem Werkzeugwechsel, da ein exaktes Einmessen entfallen kann,
• das Risiko einer Überlastung von Biegepresse und Werkzeug wird deutlich minimiert,
• im Vergleich zu bekannten Lösungen extrem wartungsarm und kostengünstig,
• es können alle bzw. verschiedene Werkzeuge verwendet werden (unabhängig von Geometrie, Hersteller oder Klemmungsart),
• eine Aufrüstung bereits vorhandener Werkzeuge ist möglich,
• die Werkzeuge werden aufgrund des berührungslosen Messprinzips nicht in ihrer maximalen Belastung beschränkt,
• verschmutzte oder beschädigte Codes werden einfach gesäubert bzw. neu aufgebracht,
• keine zusätzlichen Störkonturen an der Biegepresse oder Ketten für Datenkabel,
• die auf die Werkzeuge aufgebrachten Datamatrix-Codes können die Lagerhaltung vereinfachen: In der Beschreibung des Codes können auch entsprechende Lagerplätze, bzw. maximale Nutzungszeiten der Werkzeuge oder dergleichen hinterlegt werden;
• Abrufen von Biegeteilen und Programmen: Mit Hilfe der (Matrix)Kamera können auch Codes von Arbeitsplänen oder Blechen gelesen werden, die beispielsweise für einen bestimmten Ablauf, ein entsprechendes Programm oder eine Blechqualität stehen.

Further advantages of preferred embodiments of the invention are listed below:

• complete control of the tools used
• the bending plan can be automatically converted to real tool positions
• Significantly shorter service life of the bending press when changing tools, since exact calibration can be omitted
• the risk of overloading the bending press and tool is significantly minimized,
• compared to known solutions extremely low maintenance and inexpensive,
• all or different tools can be used (regardless of geometry, manufacturer or type of clamping),
• it is possible to upgrade existing tools,
• the tools are not limited in their maximum load due to the contactless measuring principle,
• dirty or damaged codes are simply cleaned or reapplied,
• no additional interference contours on the bending press or chains for data cables,
• the data matrix codes applied to the tools can simplify storage: in the description of the code, corresponding storage spaces or maximum usage times of the tools or the like can also be stored;
• Retrieving bent parts and programs: With the help of the (matrix) camera, codes of work plans or sheets can also be read, which, for example, stand for a specific sequence, a corresponding program or sheet quality.

In addition, the camera used can visualize the (rear) stop area. It is often difficult to position metal sheets precisely on the backgauge fingers, since the installation height of the bending press is too low or the tools used have a view of the backgauge fingers prevent. To simplify the process, the camera image, which represents the backgauge area, can be transferred to a screen visible to the operator.

It is preferably indicated on an operator interface if the position of the upper tool and / or lower tool detected with the sensor device is incorrect, in particular if the tools are not in alignment with one another. Correction values relating to the positioning of the upper tool and / or lower tool can be transferred to the control or the user interface (e.g. screen) in order to indicate to the operator that the tools are not in alignment and the position of at least one tool must be corrected.

The bending process or the setting-up process is preferably terminated if the position or position and type of the upper tool and / or lower tool detected with the sensor device is incorrect. In the case of incorrectly placed or incorrectly dimensioned tools, damage to the machine or dangers to operating personnel due to tool breakage can be excluded in this way.

The method preferably comprises a calibration of the position of the stop, the calibration preferably being carried out by means of a preferably optical position mark which is attached to a component of the bending press or to a reference tool. The (back) stop can be calibrated in the X, R and Z directions by means of an optical reference (position marking) on the upper beam, on the tool clamp, within the bending press or by means of a reference tool, so that the (back) ) Stop by hand can be omitted if the stop has been adjusted due to improper use.

The workpiece to be bent is preferably provided with a readable code, which contains a reference to an associated bending program, and that after reading out the code, the associated bending program is preferably loaded and / or processed automatically in the control device with the sensor device. A loading of the bending program associated with the bent part into the control can thus be carried out on the basis of a code on the bent part (bent or sheet metal blank) in which the associated bending program is encoded. done automatically. The code is, for example, applied to the bent part with a laser. For example, the operator holds the sheet in front of the sensor device, for example a camera, and the control automatically loads the corresponding bending program. The code can also be read out when the bent part is positioned on the stop, advantageously automatically by the sensor device.

The sensor device is preferably a camera and the images or image sequences recorded with the camera are displayed on an operator interface.

The transfer of the live camera image to the control or the operator interface enables the operator to be shown the current situation within the bending press.

• eine Bedienerführung des Bleches vor bzw. während des Anschlagen des Bleches am Anschlag mittels Kamerabild und eingeblendeten Führungslinien (ähnlich wie beim Einparken mit dem Auto);
• eine Bedienerführung beim Einsetzen der Werkzeuge mittels Kamerabild und eingeblendeten Führungslinien;
• eine Anlageerkennung des Bleches am (Hinter-)Anschlag mittels Kamera. (Wenn die Kamera erkennt, dass das Blech korrekt am Anschlag positioniert wurde, gibt die Steuerung ein entsprechendes Signal aus und der Bediener kann den Biegevorgang starten).
• eine Überwachung des Maschinenraumes durch die Kamera. Dies kann dazu verwendet werden, um die Annäherungsgeschwindigkeit des Anschlages an den Tisch zu überwachen und diesen damit schneller als bei bisherigen Biegepressen verfahren zu können.

This embodiment enables, among other things:

• an operator guidance of the sheet before or during the striking of the sheet at the stop by means of a camera image and superimposed guide lines (similar to when parking with the car);
• Operator guidance when inserting the tools using a camera image and displayed guide lines;
• system detection of the sheet at the (back) stop using a camera. (If the camera detects that the sheet has been correctly positioned at the stop, the control system issues a corresponding signal and the operator can start the bending process).
• surveillance of the machine room by the camera. This can be used to monitor the speed of approach of the stop to the table and thus to be able to move it faster than with previous bending presses.

The sensor device can also measure the deflection of the upper and lower cheeks. During the bending process, the upper and lower cheeks undergo a deflection that can be compensated for by crowning cylinders. The crowning is calculated in the control on the basis of theoretical values and is to be calculated in the future on the basis of the real state recorded by the sensor device. This enables a higher accuracy to be achieved in the bent part.

The sensor device can also be designed to detect the (sheet) thickness of the inserted (sheet) workpiece. If the workpiece corresponds to the entered data in the control device (machine control) or the corresponding values move within the defined tolerance range, the bending process can be started or continued, otherwise the bending process can be interrupted or interrupted.

Likewise, workpiece or bent part dimensions (correct cutting, correct positioning) can be recorded with the sensor device, which enables improved operator guidance.

In a preferred embodiment, the subject method also includes the creation of thermographic images of the bending press or parts thereof. This is preferably done by means of at least one IR sensor or at least one thermal imaging camera, which can be arranged within the bending press. This enables the various heating conditions of the bending press (e.g. the tools, the machine frame, etc.) to be monitored and evaluated. The machine body may expand indefinitely as a result of the heating, which leads to displacements of important reference points and thus to poorer bending results. A critical factor is a machine body that is not fully warmed, i.e. local temperature differences, such as may occur directly after the bending press is switched on. With the help of the thermographic state images, individual reference axes can compensate for the occurring displacements and thus ensure a constant bending quality.

Further advantages, features and details of the invention emerge from the following description, in which exemplary embodiments of the invention are described with reference to the drawings. The features mentioned in the claims and in the description can each be essential to the invention individually or in any combination.

The list of reference symbols is part of the disclosure. The figures are described coherently and comprehensively. The same reference symbols mean the same components, reference symbols with different indices indicate functionally identical or similar components.

Fig. 1

eine erfindungsgemässe Biegepresse von vorne,

Fig. 2

die Biegepresse aus Fig. 1 in seitlicher Ansicht,

Fig. 3

die Biegepresse aus Fig. 1 von hinten,

Fig. 4

einen Detailausschnitt einer Biegepresse von vorne, mit Ober- und Unterwerkzeug und dem Anschlag,

Fig. 5

ein Oberwerkzeug, das in einem Werkzeughalter fixiert ist,

Fig. 6

zwei Unterwerkzeuge, die in einem Werkzeughalter fixiert sind,

Fig. 7

einen möglichen Verfahrensablauf in Art eines Fliessdiagramms,

Fig. 8

eine schematische Darstellung einer Biegepresse mit Steuerleitungen und Verfahrwegen, und

Fig. 9

eine schematische Darstellung einer Verknüpfung der Sensoreinrichtung mit einer Bedienerschnittstelle der Biegepresse.

It shows:

Fig. 1

a bending press according to the invention from the front,

Fig. 2

the bending press Fig. 1 in a side view,

Fig. 3

the bending press Fig. 1 from behind,

Fig. 4

a detail of a bending press from the front, with upper and lower tools and the stop,

Fig. 5

an upper tool, which is fixed in a tool holder,

Fig. 6

two lower tools, which are fixed in a tool holder,

Fig. 7

a possible procedure in the form of a flow diagram,

Fig. 8

is a schematic representation of a bending press with control lines and travel paths, and

Fig. 9

a schematic representation of a link between the sensor device and an operator interface of the bending press.

Fig. 1 shows a bending press 1 for bending workpieces, with 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 holder 4, 5 along the Z-axis, ie parallel to the bending line, is so great that several upper and lower tools 2, 3 can be inserted and fixed side by side in the tool holder 4, 5. This case is in Fig. 6 shown where two lower tools 3 sit in the tool holder 5.

The upper tool 2 and the lower tool 3 can be fixed in different positions within the respective tool holder 4, 5. I.e. the tools can be arranged differently relative to the respective tool holder in the direction of the Z axis.

The bending press 1 has at least one stop 6 for positioning the workpiece 14 ( Fig. 2 ) within the bending press 1, the stop 6 by means of a control device 13 (in Fig. 8 shown) driven drive 9 is movable relative to the tools 2, 3. This movability relates in particular to a movability along the Z axis, however, is Movability in other - in particular perpendicular - spatial directions is also conceivable. The embodiment from Fig. 1 shows two stops 6, which can be moved independently of each other.

As seen from the side view of the Fig. 2 recognizable, the present exemplary embodiment is a backgauge, that is to say a stop which, seen from the operator side of the bending press 1, is arranged behind the tools 2, 3. The stop 6 serves a workpiece 14, for. B. to position a sheet to be bent, relative to the tools 2, 3. The back gauge can be moved parallel to the bending line (along the Z axis). The sensor device 8 is arranged on the backgauge and can be moved together with the backgauge parallel to the bending line.

In an alternative embodiment, the sensor device 8 could be independent, e.g. B. sitting in its own holder, be movable from the backgauge. However, the sensor device is preferably arranged in the region of the backgauge.

In the embodiment shown, the stop 6 comprises stop fingers 7 which are additionally movable. In addition to the stop fingers 7 there is a sensor device 8 based on the contactless measuring principle, in particular in the form of a camera. The sensor device 8 is designed for contactless detection of the position of the upper tool 2 and lower tool 3 within the bending press 1. The stop 6 is in the Fig. 3 and 4th recognizable in detail.

In the embodiment described here, the sensor device 8 detects the position of the tools 2, 3 in the direction along the Z axis, ie. H. along the bend line. This measurement can be carried out 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.

Fig. 8 shows a schematic representation of the functional relationships in a bending press 1 according to the invention, which also includes a control device 13 for controlling the bending press 1. The control device 13 controls in particular the drive 12 for the upper tool 2 and thus the actual pressing process. Another 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,

The control device 13 is now designed to adapt the movement process with which the at least one stop 6 is positioned relative to the tools 2, 3 as a function of the position of the upper tool 2 and the lower tool 3 detected by the sensor device 8.

As an example, two possible positions of upper tool 2 and lower tool 3 are shown, one of which is dashed. For the first position (solid line), a travel z _{1 is} calculated depending on the position in order to align the stop 6 with respect to the tools 2, 3. The stop 6 does not necessarily have to lie behind the tool, as shown, but other positions relative to the tool are also conceivable, depending on the bending plan.

For the second position (dashed line), a travel path z _{2 is} calculated depending on the position in order to align the stop 6 with respect to the tools. With this principle, the approach coordinates of the stop 6 are adapted to the respective position of the tool, so that a corresponding bending process can be carried out in accordance with the bending plan. The adaptation or adaptation of the movement process can of course also relate to the movements of the stop fingers 7.

Also like in Fig. 6 indicated - several tools are seated in a tool holder, whereby several bending line sections are defined. The associated bends can be transferred to the workpiece simultaneously or one after the other. In any case, the starting coordinates of the stop 6 are automatically adjusted.

• Schritt 20: Bestücken der Biegepresse mit zumindest einem Oberwerkzeug und/oder zumindest einem Unterwerkzeug, das/die innerhalb des jeweiligen Werkzeughalters fixiert wird/werden.
• Schritt 21: Erfassen der Position des Oberwerkzeuges 2 und/oder Unterwerkzeuges 3, die in den jeweiligen Werkzeughaltern 4, 5 fixiert sind, innerhalb der Biegepresse 1 mittels der Sensoreinrichtung 8. Beispielsweise kann vor und/oder während des Schrittes 21 die Sensoreinrichtung 8 parallel zur Biegelinie (d. h. entlang der Z-Achse) verfahren werden.
• Schritt 22: Anpassen des Bewegungsvorganges, mit dem der zumindest eine Anschlag 6 relativ zu den Werkzeugen 2, 3 positioniert wird, in Abhängigkeit der mit der Sensoreinrichtung 8 erfassten Position des Oberwerkzeuges 2 und/oder Unterwerkzeuges 3. Dieser Schritt kann beispielsweise dadurch erfolgen, dass ein Verfahrweg z₁, z₂ des Anschlages 6 parallel zur Biegelinie (d. h. entlang der Z-Achse) berechnet wird.
• Schritt 23: Positionieren des zumindest einen Anschlages 6 entsprechend dem angepassten Bewegungsvorgang durch Verfahren des Anschlages 6 mittels eines durch die Steuereinrichtung 13 angesteuerten Antriebes 9 relativ zu den Werkzeugen 2, 3.
• Schritt 24: Durchführen eines Biegevorganges durch relatives Verfahren von Oberwerkzeug 2 und/oder Unterwerkzeug 3.
• Schritt 25: Austauschen und/oder Hinzufügen von Ober- und/oder Unterwerkzeugen sowie deren Fixierung in dem jeweiligen Werkzeughalter.

The method for bending a workpiece with a bending press 1 can now include the following steps, which are shown in the flow diagram of FIG Fig. 7 are shown:

• 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.
• 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 means of the sensor device 8. For example, before and / or during step 21, the sensor device 8 can be parallel to Bending line (ie along the Z axis).
• Step 22: adapting the movement process with 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 can be carried out, for example, in that a travel path z ₁ , z _{2 of} the stop 6 parallel to the bending line (ie along the Z axis) is calculated.
• Step 23: positioning the at least one stop 6 according to the adapted movement process by moving the stop 6 by means of a drive 9 controlled by the control device 13 relative to the tools 2, 3.
• Step 24: Execution of a bending process by relative movement of upper tool 2 and / or lower tool 3.
• Step 25: Exchange and / or add upper and / or lower tools and fix them in the respective tool holder.

Steps 21 to 25 can then be repeated.

The position of the upper tool 2 and the position of the lower tool 3 arranged at the same height are preferably detected simultaneously. For this purpose, the sensor device 8 can be moved into a position in which the detection area of the sensor device 8 at least partially includes both the upper tool 2 and the lower tool 3.

The 5 and 6 show preferred variants of the invention, 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.

The detection or detection of the position of the upper tool 2 and / or lower tool 3 can take place in this embodiment with the help of this scale 10. For this purpose, image recordings of the sensor device 8 designed as a camera are evaluated with regard to the relative position of the tool in relation to the scale (for example by using appropriate image recognition software). Like from the 5 and 6 can be seen, the scale division extends parallel to the bending line.

The position of the upper tool 2 and / or lower tool 3 is preferably detected by a contour detection of the tool 2, 3 using corresponding image processing programs.

In a preferred variant, a two-dimensional code 11, in particular a data matrix code (from an arrangement of black and white rectangles within 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 the type and dimensions of the tool 2, 3.

A code 11 is advantageously applied to both the front and the back of a tool 2, 3. Thus, the tool 2, 3 can also be inserted mirror-inverted into a tool holder 4, 5 and easily recognized by the sensor device 8.

In this embodiment, the code information can also be read out by means of the sensor device 8. It can then be checked whether a tool complies with the specified specifications or is compatible with the bending plan.

Fig. 9 shows an embodiment in which the sensor device 8 comprises two non-contact sensors with different spatial detection ranges. The sensors here are optical sensors, especially cameras. The cameras depict different areas along the bending line Z (also called the Z axis). The detection areas of the sensors can overlap.

Furthermore is out Fig. 9 to see that the bending press comprises an operator interface 27 (here in the form of a screen), which is connected to the control device 13 or the sensor device 8. Sensor data of the sensor device 8 and / or data derived from the sensor data can be displayed on the operator interface 27. This data can be automatically output on the operator interface 27 during operation.

The sensor device 8 can also comprise only one sensor or camera. In particular, the images or image sequences recorded with the camera can be displayed on the user interface 27.

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 is not correct, especially if the tools 2, 3 are not in alignment. This information, which can also already contain correction values, enables the operator to easily correct the position of the tools 2, 3.

The invention is not restricted to the described embodiments and the aspects emphasized therein. Rather, a large number of modifications are possible within the scope of the inventive concept, which lie within the framework of professional action. It is also possible to implement further design variants by combining the means and features mentioned without leaving the scope of the invention.

Reference symbol list

1

Bending press

2nd

Upper tool

3rd

Lower tool

4th

Tool holder for upper tool 2

5

Tool holder for lower tool 3

6

attack

7

Stop finger

8th

Sensor device

9

Actuator for stop 9

10th

Scale

11

code

12

Upper tool drive 2

13

Control device

14

workpiece

20-26

Procedural steps

27th

Operator interface

Z

Bending line

Claims (17)

1. A bending press (1), in particular a press brake, for bending workpieces (14) 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),

   - at least one stop (6) for positioning the workpiece within the bending press (1), wherein the stop (6) is movable in relation to the tools (2, 3) by means of a drive (9) controlled by the control device (13), wherein
   the sensor device (8) is designed to detect the position or the position and the type of the upper tool (2) and of the lower tool (3) within the bending press (1), without contact, characterised in that
   the control device (13) is designed to adapt the movement process by means of which the at least one stop (6) is positioned in relation to the tools (2, 3), in dependence on the position or the position and the type of the upper tool (2) and of the lower tool (3) detected by means of the sensor device (8).
2. The bending press according to claim 1, characterised in that the at least one workpiece-positioning stop (6) is a rear stop, which can be moved parallel to the bending line, and in that the sensor device (8) is arranged in the region of the rear stop.
3. The bending press according to claim 1 or 2, characterised in that the sensor device (8) is arranged on the stop (6) and, together with the stop (6), can be moved preferably parallel to the bending line.
4. The bending press according to any one of the preceding claims, characterised in that the sensor device (8) can be moved into a position in which the detection range of the sensor device (8) at least partially comprises both the upper tool (2) and the lower tool (3); and/or
   in that the sensor device (8) is a camera.
5. The bending press according to any one of the preceding claims, characterised in that a scale (10) or a position marking is applied to the upper tool (2) and/or the lower tool (3) and/or the respective tool holder (4, 5); and/or in that a two-dimensional code (11), in particular a data matrix code, is applied to the upper tool (2) and/or the lower tool, wherein preferably the code (11) contains information about the tool (2, 3) used, in particular about the type and dimensions of the tool (2, 3).
6. A method for bending a workpiece (14) with a bending press (1) according to any one of the preceding claims, characterised by the steps of:

   - detecting the position or the position and the type of the upper tool (2) and/or the lower tool (3), which are fixed in the respective tool holders (4, 5), within the bending press (1) by means of the sensor device (8),

   - adapting the movement process with which the at least one stop (6) is positioned relative to the tools (2, 3) in dependence on the position or the position and the type of the upper tool (2) and/or the lower tool (3) detected by the sensor device (8),

   - positioning the at least one stop (6) according to the adapted movement process by adjusting the stop (6) by means of a drive (9) controlled by the control device (13), relative to the tools (2, 3),

   - carrying out a bending process by relative movement of the upper tool (2) and/or the lower tool (3).
7. The method according to claim 6, characterised in that during the step of detecting the position or the position and the type of the upper tool (2) and/or the lower tool (3), its/their position relative to the respective tool holder (4, 5) in which the tool (2, 3) is fixed, is detected.
8. The method according to claim 6 or 7, characterised in that during the step of adapting the movement process, a travel path (z₁, z₂) of the stop (6) is calculated parallel to the bending line.
9. The method according to any one of claims 6 to 8, characterised in that before and/or during the step of detecting the position or the position and the type of the upper tool (2) and/or the lower tool (3), the sensor device (8) is moved parallel to the bending line.
10. The method according to any one of claims 6 to 9, characterised in that the position or the position and the type of the upper tool (2) and the position or the position and the type of the lower tool (3) are detected simultaneously.
11. The method according to any one of claims 6 to 10, characterised in that the detection of the position of the upper tool (2) and/or the lower tool (3) is carried out by means of a scale (10) or position marking applied to the upper tool (2) and/or the lower tool (3) and/or the respective tool holder (4, 5).
12. The method according to any one of claims 6 to 11, characterised in that the position detection and/or the type identification of the upper tool (2) and/or the lower tool (3) is carried out by means of contour identification of the tool (2, 3).
13. The method according to any one of claims 6 to 12, characterised in that the method comprises a step of reading information from a two-dimensional code (11) applied to the upper tool (2) and/or the lower tool (3), in particular a data matrix code.
14. The method according to any one of claims 6 to 13, characterised in that a user interface (27) indicates if the position of the upper tool (2) and/or the lower tool (3) detected by the sensor device (8) is incorrect, in particular if the tools (2, 3) are not aligned; and/or
    in that the bending process or the setting-up process is interrupted if the position or the position and the type of the upper tool (2) and/or the lower tool (3) detected by the sensor device (8) is incorrect.
15. The method according to any one of claims 6 to 14, characterised in that the method comprises a calibration of the position of the stop (6), wherein the calibration is preferably carried out by means of a preferably optical position marking, which is attached to a component of the bending press (1) or attached to a reference tool.
16. The method according to any one of claims 6 to 15, characterised in that the workpiece (14) to be bent is provided with a readable code which contains a reference to an associated bending program, and in that after the code has been read, preferably with the sensor device (8), the associated bending program is automatically loaded and/or processed in the control device (13).
17. The method according to any one of claims 6 to 16, characterised in that the sensor device (8) comprises at least one camera and the images or image sequences recorded with the camera are displayed on an operator interface (27).

Images