Angle measuring device for a press brake

The invention relates to an angle measuring device for a bending press.

For the production of precisely shaped bent parts compliance with the bending angle required by the design is of particular importance, so that the formed angle is determined during or after the bending process, compared with the desired target angle and, if necessary, a further bending process must be carried out. However, this requires additional process steps, since to measure the angle, the press has to be opened so far that the bending part is relieved and that access to the bent angle with angle measuring devices is possible. In particular, such a measurement is always associated with a delay in the workflow.

To reduce the effort involved in checking the angle, it is known from the prior art to integrate the measurement of the angle into the bending process, so that the bent angle can be determined without the intervention of an operator. In this regard, DE 10 2008 038 932 A1, for example, discloses a swivel bending machine in which a light sensor is arranged in the bending tool, which detects the point in time and thus the angle at which light enters the gap when the bending part is relieved, i.e. when the bending beam is swiveled back falls between the bent workpiece and the bending beam. Knowing the pivoting angle of the bending beam allows conclusions to be drawn about the bent angle.

Another embodiment is known from DE 43 12 565 C2, in which a light source directs a light trail onto the cheeks of the bent workpiece, which light trail is recorded by a camera arranged on the press beam and this recorded image is analyzed by an evaluation device to calculate the bending angle from this. The light source is in the punch or arranged integrated in the counter tool, so that a light trail can be formed on the sheet metal limb when the tool is moved together. Since the image recording means must be able to capture the light trail on the sheet metal cheeks, it must be aligned at a corresponding angle to the section of the bent part illuminated by the light trails. When the sheet metal part is pressed into the counter tool, the bending punch will at least partially cover the work area, so that detection by the camera is no longer possible.

From JP 2-280920 A an angle measuring device is known in which an image recording device detects the end face of a bent sheet metal part and determines the bending angle via an image evaluation device. To ensure a high quality of resolution, it is disclosed that the distance between the image capturing device and the end face of the workpiece is determined and the focusing device of the image capturing device is set accordingly to this distance.

When bending longer parts, due to the forces acting, there is always the risk that, for example, the machine bed or the press beam will deform slightly, so that the bending angle in the middle of the bending part can be different compared to the edge sections. In order to form a correct bending angle, it is therefore not expedient to detect the end faces of the bending part, since this only allows a local snapshot to be formed. The design known from the prior art, according to which an optical detection device is integrated in the bending tool, has the disadvantage, however, that very complex and therefore very expensive tools have to be produced and that the arrangement of the detection device in the tool structurally weakens it, so that there is also the risk of incorrect bending. It is also necessary for this to determine the position of the angle measurement along the bending line before the bending is carried out, since the detection device has to be arranged in the desired section. Such a configuration therefore requires a considerable amount of manipulation and thus a delay in the bending process.

The formation of a detection device as a camera, which at an angle to / 16

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Patent Office directed an illuminated section of the sheet metal part, has the disadvantage that a lowering and bending punch restricts the field of vision of the camera on the workpiece and thus the essential section for the detection of the bending angle is covered by the bending punch. Furthermore, since the detection of a light trail on the bending part and the subsequent determination of the angle requires a certain minimum angle at which the camera must be directed at the workpiece, there is a risk, especially with long bending parts, that only a section of the bending part with such a Angle measuring device can be evaluated.

The devices known from the prior art now have the particular disadvantage that the determination of the bending angle either requires very complex bending tools, or that the angle determination is essentially only possible for the edge sections of the bending part.

The object of the invention is to create an angle measuring device in which the bending angle can be determined contactlessly and along the bending line without the need for expensive or complex bending tools. In particular, the angle measuring device according to the invention should be easy to retrofit for existing bending presses.

The object of the invention is achieved by an angle measuring device in which a lighting device with at least one illuminant illuminates a portion of the surface of the sheet metal part on at least one side of the working plane, the working plane through the direction of travel of the press beam and through the bending line, as a contact line is clamped between the press beam and the sheet metal part. According to the invention, the optical axis of an optical image acquisition device is arranged in the working plane and, furthermore, the optical axis and the bending line enclose an angle of less than 2 ° in the illuminated section.

By this angle, which corresponds to an almost parallel arrangement of the optical axis and the bending line, it is ensured that along the bending line each illuminated section can be recorded by the image capture device without the detection area by the lowering and bending die performing the bending completely is covered. When a section of the sheet metal part is illuminated by a light source, the individual rays of the beam incident on the sheet metal part are diffusely reflected due to the given surface roughness of the sheet metal part. For the angle measuring device according to the invention, however, only those reflected rays are relevant or are recorded by the image capturing device, which leave the illuminated section at a very small angle in relation to the bending line, that is, quasi parallel to the bending line, and thus enter the detection area of ​​the image capturing device. This also ensures in particular that no direct components of the beam leaving the lighting means are recorded by the image capturing device. By positioning the lighting device along the bending line, the angle measuring device according to the invention makes it possible to determine the bending angle at any point without restricting the angle determination by the components involved in the bending process.

In addition to the solution set out above for the bending press described, the object of the invention is also achieved in that the optical axis and a normal projection track of the optical axis on the surface of the sheet metal part in the illuminated section enclose an angle of less than 2 °. In this embodiment, an optical image acquisition device is arranged to the side of the press beam, so that the angle between the optical axis and the bending line has a component parallel to the working plane and a component normal to the working plane. The development ensures that, according to the invention, the image capturing device captures only those radiation components which leave the illuminated section essentially parallel to the sheet metal surface. The image capturing device is arranged in such a way that the angle according to the claims is formed in any case when the desired bending angle is reached. During the bending process

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Patent Office, this angle steadily decrease from a starting angle. With this design, half the bending angle is determined so that, assuming a symmetrical course of the bending, the entire bending angle is obtained from twice the angle determined according to this design.

According to the invention, the lighting device is formed by at least one lighting means, which can be arranged, for example, centrally on the press beam and thus illuminates sections on both sides of the working plane. According to a development, the lighting device can have at least two lighting means, which lighting means are arranged on both sides of the working plane, in particular on the press beam. This design has the particular advantage that the two illuminants can, for example, be arranged very easily directly on the press beam and aligned with the section to be illuminated and thus always maintain their position correctly aligned when the press ram is lowered. For example, the lighting means can have a magnetically acting holding device and are therefore very easy to attach to the metallic press beam. This has an advantage in particular for service or configuration tasks and also enables a very simple definition of the position along the bending line at which the angle measurement is to take place.

Since it is of particular interest, especially for long bent parts, to detect the bending angle in the central areas of the bending line, a further development is advantageous, according to which the illuminant is arranged to be displaceable in the direction along the bending line. For example, a longitudinal guide can be arranged on the press beam or on the machine frame, on which the lighting means is arranged or in which guide rail a guide of the lighting means engages. In the course of setting up the machine or during bending monitoring, the light source can now be moved into the position at which the bending angle is to be recorded. The advantage of this further development is that the alignment of the lighting means on the section to be illuminated is reliably maintained, regardless of the arrangement position. This design also enables the measuring position to be adjusted very quickly and easily without the need for complex reconstruction work on the bending press.

To simplify the measurement and in particular with regard to the automation of the measurement, a further development is advantageous, according to which the lighting device has a selectively controllable drive means which is in operative connection with the lighting means. For example, the drive means can be formed by a linear motor which is selectively controlled by a control module, which is preferably arranged in the image evaluation device, in order to move the lighting means to the desired position along the bending line. It is also possible that the drive means is formed, for example, by a revolving cable system, the lighting means being guided in a longitudinal guide and being moved to the desired position by a positioning motor by means of the cable pull.

To simplify the angle measurement and to increase the throughput or with regard to the best possible automation, a further development is also advantageous, according to which a plurality of illuminants are arranged in the direction along the bending line. The lighting means are preferably selectively controlled by a control module of the image evaluation device in order to illuminate a sheet metal section on both sides of the plane of travel. According to a further development, it can be provided that the lighting means are activated cyclically in order to be able to continuously determine the currently bent angle at a plurality of positions along the bending line during the bending process.

Since strong vibrations can occur again and again when the angle measuring device is used as intended, a further development is advantageous, according to which the lighting means is formed by a semiconductor component. Such semiconductor components are very advantageous with regard to their mechanical resistance, since they can withstand major vibrations without damage due to their structural structure. In contrast to thermal radiators, it is also advantageous that such semiconductor components have a smaller

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Have self-heating and thus make lower safety requirements necessary in the vicinity of flammable lubricants or hydraulic oils. Another advantage is the significantly higher optical efficiency and the lower energy consumption, with a high luminance at the same time.

According to a further development, the illuminant has a club-shaped radiation pattern, which has the advantage that the predominant luminous flux emitted by the illuminant is directed in a radiation lobe onto the section to be illuminated and thus a high luminance is achieved there, which is the case in the direction The radiation components diffusely reflected from the image capturing device is advantageous, since the captured light intensity will thus be higher. The lighting means can for example have a reflector with focusing optics in order to emit the radiation in a correspondingly club-shaped manner. The club characteristics also ensure that no direct radiation components of the illuminant get in the direction of the detection device. For example, a light-emitting diode can be used as the lighting means, which in one possible embodiment has an opening angle of the radiation characteristic between 45 ° and 65 °.

According to a further development, the lighting means has a directional radiation pattern with an opening angle less than 10 °, which has the advantage that by means of a directional radiation pattern, such as that emitted by a laser, for example, the portion to be illuminated on the sheet metal part has a high Will have luminance, because with a directed radiation pattern, the entire luminous flux emitted by the illuminant is directed onto the section to be illuminated.

To increase the luminance in the section to be illuminated or to suppress scattered light, which can optionally reach the image capturing device directly from the light source, a further development is advantageous, according to which the lighting device has a beam shaping device, in particular to a Generate luminous patterns. The luminous pattern can, for example, be a strip with a preferred width, which illuminates the sheet metal part normal to or at an angle to the bending line. A line pattern can also be applied in order to illuminate discrete sections on the sheet metal part. The beam shaping device can be formed, for example, by a diaphragm or lens system, but prism systems or scanning deflection systems are also possible.

A further development according to which the lighting device is arranged integrated in the press beam or in the punch is also advantageous. This design achieves a very close arrangement of the lighting device on the bending line, which has the advantage that an undesired incidence of light from the lighting device directly on the image capture device can be largely suppressed and that even if the stamp is deeply immersed in the bending tool, a there is good lighting of the sheet metal part in the area of ​​the bending line.

Since the invention provides to detect the bending angle along the bending line and therefore the image capturing device must be well adapted to the respective section to be captured, a further development is advantageous, according to which the image capturing device has a focusable and / or selectively adjustable focal length Has optics. By setting the focal length of the optics, the focal point can be placed exactly on the section to be captured, so that for each section to be captured along the bending line, there is an adapted capture optics; in particular, the image opening angle of the optics is adapted to the capture area using optics that can be adjusted in focal length being. As a result of the selective focusing, the focal point in the detection area can be selected in such a way that the highest possible light intensity is detected. If necessary, the focal point can be varied slightly, with an averaging being carried out by the image evaluation device, in order to thus acquire an intensity of the detected reflection that is as delimited as possible and at the same time high. The more clearly the detected reflected radiation is restricted to a narrow section of the detection area, the more precisely a line can be drawn from it

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Form patent office.

With regard to automation, a further development is advantageous, according to which the selectively adjustable optics are connected to an adjusting means of the image evaluation device, since this enables the optics of the image capturing device to be set automatically and therefore not by the operator. This setting is preferably carried out by a control module of the image evaluation device.

Since, according to the invention, the optical axis of the image capturing device and the bending line in the illuminated section enclose an angle, but this angle is very small, so that an approximately parallel alignment of the optical axis and the bending line is given, a development is advantageous after the the image capturing device is arranged to be pivotable, in particular is designed to be pivotable by an adjusting means. Since according to the invention only the scattered light of the illuminated section is detected, which scattered light leaves the illuminated section quasi parallel to the sheet metal surface in the direction of the image capturing device, there are very small angular dimensions in the case of illuminated sections that are far away from the image capturing device along the bending line, so that is advantageous if in this case the viewing angle of the image capturing device on the illuminated portion can be changed, in particular can be enlarged. For example, the position of the image capturing device along the plane of travel can be changed by choosing a larger distance between the optical axis and the bending line. In addition, the optical axis can be inclined towards the bending line, so that the viewing angle for distant, illuminated sections is improved, i.e. the angle between the optical axis and the bending line is changed. Since the optical axis of the image capturing device is arranged in the plane of travel, this adjustment range will have to be very small in order not to cover the illuminated section by the punch moving down.

Another possibility for preventing direct incidence of light from the light source on the image capturing device is characterized in that a polarization element is arranged in the beam path of the illuminant and in the optics of the image capturing device, the polarization planes of the two polarization elements enclosing an angle greater than 0 ° . However, this angle is preferably a right angle or be an approximately right angle, so that those radiation components emanating directly from the light source cannot reliably pass the polarization element of the image capturing device. With this development, part of the light diffusely reflected in the illuminated section is lost for the evaluation, but the evaluation reliability can be increased by simplifying the evaluation, since no undesired scattered light is to be expected.

A further development consists in that an optical image capturing device is arranged on both sides of the working plane. This means that both bending legs can be detected at the same time and the entire bending angle can be determined.

Since, according to an embodiment of the invention, the arrangement of the image capturing device must be adapted to the bending angle to be achieved, in particular the image capturing device is to be arranged in such a way that when the desired bending angle is reached, the angle according to the invention is set between the optical axis and the normal projection track Further development provided that the image capturing device is arranged on a positioning device, which positioning device is designed to be adjustable at least in the direction parallel to the working plane. Thus, the image capturing device can be moved to the corresponding position before the bending process, for example by moving it along a longitudinal guide, which can be arranged on the machine frame.

For automated production, in particular to simplify the setting, a further development is advantageous, according to which the positioning device is connected to a machine control, since a direct and in particular automated setting option is thus given. For example, the positioning device can have a longitudinal guide, in

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Patent Office which the image capturing device is arranged displaceably, the displacement movement being brought about by a drive means controlled by the machine control.

For a better understanding of the invention, it is explained in more detail with reference to the following figures.

[0030] In each case, in a highly schematically simplified representation, the following are shown:

[0031] FIG. 1 shows an illustration of a bending press with the angle measuring device according to the invention;

[0032] FIG. 2 shows a basic illustration of the determination of the bending angle;

3 a) to c) a further possible embodiment of the angle measuring device according to the invention.

1 shows an angle measuring device according to the invention on a bending press 1, the bending press 1 having a press table 2 with a bending die 3 and a press beam 4 with a punch 5 that is movable relative thereto. The press beam 4 is moved towards the bending die 3 in a travel direction 7 by drive means 6, the punch 5, in particular the working edge of the punch, making contact with a sheet metal part 8 to be formed along the bending line 9. The bending line 9 and the direction of travel 7 span the working plane 10.

The angle measuring device according to the invention now has a lighting device 12 with a lighting means 13, an optical image capturing device 14 and a data processing image evaluation device 15. The three components are preferably in terms of data or communicatively connected to one another so that, for example, a control module of the image evaluation device 15 controls the activation of the luminous means 13 of the lighting device 12 and at the same time initiates the image acquisition by the image acquisition device 14. A user interface 16, in particular an input / output device, is preferably connected to the image evaluation device 15 in order to present the result of the angle detection to the operator of the bending press 1 so that he can continue the bending process until the desired bending angle is reached. For automated bending, the image evaluation device can also be connected directly to the control of the bending press 1 or For example, the image evaluation device 15 can be part of the control of the bending press 1, so that the required bending angle is produced automatically and in particular without any operator action.

According to the invention, a beam 17 is emitted from the lighting means 13 onto a section 18, on at least one side of the working plane 10, of the surface of the sheet metal part 8 to be formed. The lighting means can be formed, for example, by a light-emitting diode which, due to its structural design or due to an existing beam shaping device, emits a beam 17 in the direction of the sheet metal part 8. Since the optical axis 20 of the image capturing device 14 is arranged in the working plane 10 and also approximately parallel to the bending line 9, only those rays of the beam 17 incident on the section 18 are captured by the capture area of ​​the image capturing device 14 which, due to the diffuse reflection in the section 18, are reflected essentially parallel to the sheet metal surface. According to the invention, the optical axis 20 and the bending line 9 in the illuminated section 18 enclose an angle 21 of less than 2 °. This small angular dimension justifies the specification of a quasi-parallel arrangement of the optical axis 20 and the bending line 9. In order to be able to represent the angular relationships, the thickness of the sheet metal part 8 and the arrangement of the image capturing device 14, in particular the distance 22 of the optical axis 20 from the bending line 9 and the angle 21 resulting from this arrangement, have been exaggerated. The inventive arrangement of the image capturing device 14 now ensures that it is largely ensured that no direct light from the lighting device 12 reaches the capturing area of ​​the image capturing device 14 and that the image capturing from the 7 press beam 4 moving down is not impaired even during the bending process and, in particular, that the Detection of the bending 6/16

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Angle is possible at any point along the bending line 9 and not only, as known from the prior art, on the end portion of a sheet metal part facing an image detection device.

According to an advantageous development, however, it is also provided that the lighting device 12 is designed in such a way that a section on the sheet metal surface 8 is illuminated on both sides of the working plane 10. For this purpose, a light source can be attached, for example, on both sides of the working plane; these are preferably arranged on the press beam. With such a design it is also possible to determine the bending angle at two different positions along the bending line at the same time by arranging two lighting means at different positions or activating lighting means arranged at different positions.

According to a development it is provided that the lighting device 12 is arranged displaceably in the longitudinal direction of the bending line. For this purpose, a guide device 23, for example a toothed rack, is arranged on the press beam 4, in which a drive means 24 of the lighting device 12 engages, the drive means 24 being selectively controlled by a control module of the image evaluation device 15 in order to move the lighting device to the desired position along the bending line move and thus also move the illuminated section accordingly. With this development it is possible at any time during the bending process to record the currently formed bending angle at any section along the bending line without manual measurements being necessary or without the sheet metal part 8 having to be removed from the bending press 1 for measurement . In this regard, it is also advantageous if, according to a further development, the image detection device 14 can be adjusted in its focal length, preferably again by a control module of the image evaluation device 15, so that the operator can make several angle measurements at different positions along the line at any time during the bending process and without additional adjustment effort Bending line 9 can perform.

To adjust the angle 21 between the optical axis 20 and bending line 9, it can be provided according to a development that the image capturing device 14 is pivotably arranged, in particular that the distance 22 between the image capturing device 14, in particular the optical axis 20, and the bending line 9 and the pivoting of the image capturing device in the travel plane 10 is adjustable. If, for example, an angle is to be recorded at the maximum distant section of the sheet metal part, the large length distance will result in a very small angle 21 between the optical axis 20 and the bending line, which will have a negative effect on the readout accuracy. If, in this case, the image acquisition device 14 is removed somewhat further from the bending line, an angle 21 which is more favorable for image acquisition is established, so that, in turn, more diffusely reflected light is acquired.

FIG. 2 shows an exemplary representation of the image captured by the image capture device on a display device 25 of a user interface. For reasons of illustration, both the end face area 26 and the end area 27 spaced therefrom are shown in sharp focus. Due to the focal length setting and focusing of the image capturing device, the focus area of ​​the imaging optics is preferably set on the illuminated section 18, so that in particular the end areas 26, 27 are mostly displayed out of focus. Due to the quasi-parallel arrangement of the optical axis and the bending line 9 according to the invention, only those rays of diffuse reflection are detected by the illuminated section 18 which leave the illuminated section quasi parallel to the sheet metal surface 28 in the direction of the detection area of ​​the image detection device. In FIG. 2, these diffusely reflected radiation components are shown in a simplified manner by light points 29. Because of the surface roughness that is always present, the point of reflection will be statistically distributed over the illuminated section, so that no clearly straight and sharply delimited reflection is recorded, but essentially a reflection band. The individual reflection points are then analyzed by an interpolation process analy7 / 16

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Patent office and generated an interpolation line 30, for example by averaging for the reflection points on each cheek of the sheet metal part 8. The angle between the two interpolation straight lines 30 is now the bending angle 31 at the position of the illuminated section 18.

Since, according to a further development, the lighting device is designed to be longitudinally displaceable or that several illuminants are arranged in the longitudinal direction, the currently formed bending angle 31 can now be determined during the bending process at several positions along the sheet metal part and thus by correspondingly pressing the stamp or by a mechanical counter-control of the bending die or of the press table and / or by differently controlling the drive means of the press beam, the formed bending angle is corrected and the desired bending angle can thus be produced along the sheet metal part.

3a to 3c show a further embodiment of the angle measuring device according to the invention, in which the optical axis of the image capturing device is arranged essentially parallel to the working plane.

3a shows a side view of the machine frame 11, the viewing direction being arranged in the working plane 10. A lighting device 12 with a lighting means is arranged on the press beam 4 and emits a beam 17 onto the surface 32 of the sheet metal part 8, so that a section on the surface 32 is illuminated. This illuminated section is captured by an image capturing device 14, the optical axis of the image capturing device 14 being arranged essentially parallel to the working plane 10, as will be described in detail in the following figures.

An embodiment is advantageous according to which a lighting device 12 and an image capturing device 14 are arranged on both sides of the working plane 10, since both flexural legs can thus be captured at the same time and thus the entire flexural angle 31 can be captured. In Fig. 3a it is also shown that the image capturing device 14 must be arranged in such a way that when the desired bending angle 31 is reached, the image capturing device 14 can capture the illuminated section on the surface 32 of the sheet metal part 8, so that the optical axis must be above the sheet metal surface. This alignment is described in more detail in the following figures.

3b shows a view of the sheet metal part 8, the viewing plane lying in the surface 32 of the sheet metal part 8.

In an embodiment with two lighting devices on both sides of the working plane, a section 18 is illuminated on the surface 32 on both legs of the sheet metal part 8. Due to the selected view, Fig. 3b the bending line 9 together with the normal projection track 33, whereby according to the invention the angle 21 between the optical axis 20 of the image capturing device 14 and the normal projection track 33, the optical axis 20 onto the surface 32 of the sheet metal part, is less than 2 °. To illustrate the relationships, this angle is shown clearly exaggerated in the figure.

Upon reaching the bending deformation, the detection area of ​​the image capture device 14 must be directed to the illuminated section 18 of the sheet metal surface 32 of the sheet metal part, in particular to form the angle according to the invention between the optical axis 20 and the normal projection track 33. For this purpose, the image capturing device 14 is preferably arranged on a positioning device 34, which positioning device is preferably arranged on the machine frame 11. The positioning device 34 will in turn have a drive means which is connected, for example, to the machine control so that the drive means of the positioning device is controlled accordingly and the image capturing device is moved to the corresponding position before the bending deformation is carried out. This is particularly possible in an automated manner, because at this point in time, due to a stored programming or stored work instruction, the bending angle to be trained is already known and thus the adjustment work for positioning the image capture device is relieved of the operator.

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3c shows a view parallel to the bending line 9 of the image capturing device 14. In FIG. 3c, two possibilities are shown as to how the image capturing device 14 can be arranged in a positioning device 34, the arrangement in the positioning device not being absolutely necessary , since the image capturing device can optionally be arranged directly on the machine frame.

In one possible embodiment, the image capturing device 14 is arranged in the positioning device so as to be displaceable parallel to the working plane, and is moved in the positioning device by means of a drive means 35 so that the exit point of the optical axis 20 is moved parallel to the working plane 9.

When bending very small bending angles 31, an arrangement of the image capturing device 14 according to the embodiment shown on the right in the figure can lead to a reduction in the captured, illuminated section, since the image capturing device in particular usually has a rectangular image capturing area. Therefore, a training as shown in Fig. 3c, shown on the left, is advantageous because it allows the largest possible area of ​​the illuminated sheet metal surface to be captured even for very small bending angles. Here, too, the image capturing device 14 is again accommodated displaceably in a positioning device 34 and is preferably displaced along the direction of movement by a drive means 35 in order to be able to adapt the position to the angle 31 to be bent. The direction of displacement will preferably be aligned essentially normal to the sheet metal surface.

In order to be able to make the greatest possible use of the detection width of the image capturing device 14, a further development is advantageous, according to which the image capturing device 14, as shown, for example, in FIG. 3c on the right, additionally about an axis through the exit point of the optical axis 20 is designed to be pivotable. Thus, the image capturing device can be pivoted about the axis of rotation during the movement parallel to the working plane 9, so that the largest possible capture width is always arranged essentially parallel to the sheet metal surface.

In a further development, it is also possible to successively track the image acquisition device to the moving sheet metal leg as the bending deformation progresses, in order to be able to detect a direct and immediate course of the bending deformation.

In FIG. 3, a further and possibly independent embodiment of the angle measuring device is shown, the same reference numerals or component names being used for the same parts as in the previous figures. In order to avoid unnecessary repetition, reference is made to the detailed description in the preceding figures.

For the sake of clarity, it should finally be pointed out that, for a better understanding of the structure of the angle measuring device, it or its components have been shown partially not to scale and / or enlarged and / or reduced.

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REFERENCE SIGNS LISTING

Bending press

Press table

Bending die

Press beam

rubber stamp

Drive means

Direction of travel

Sheet metal part

Bending line

Working level

Machine frame

Lighting device

Bulbs

Optical image capture device

Data processing image evaluation device

User interface

Bundle of rays

Illuminated section

Opening angle

Optical axis

angle

distance

Guide device

Drive means

Display device

Face

End area

Sheet metal surface

Point of light

Interpolation line

Bending angle

surface

Normal projection track

Positioning device

Drive means

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