EP3948456A1

EP3948456A1 - Offset compensation method

Info

Publication number: EP3948456A1
Application number: EP20717548.0A
Authority: EP
Inventors: Simon OCKENFUSS; Harald MATHIAS
Original assignee: Trumpf Werkzeugmaschinen SE and Co KG
Current assignee: Trumpf Werkzeugmaschinen SE and Co KG
Priority date: 2019-04-01
Filing date: 2020-03-31
Publication date: 2022-02-09
Also published as: JP7295266B2; WO2020201245A1; JP2022527522A; CN113632021A; US12055911B2; DE102019108388A1; US20220187782A1

Abstract

The invention relates to a method for detecting and compensating for a degree of offset between the punching coordinates of a punching device and the laser coordinates of a laser device when using a combination punch-laser machine for machining a plate-shaped workpiece, in particular sheet metal. The method has the following steps: a. introducing a structure into the plate-shaped workpiece by means of the punching device or by means of the laser device; b. ascertaining a measurement variable of the structure which is introduced using the laser device or using the punching device; c. comparing the measurement variable with an expected variable, wherein a deviation between the measurement variable and the expected variable corresponds to a degree of offset; and d. calculating the degree of offset using the coordinates of the laser device in the laser coordinate system or the coordinates of the punching device in the punching coordinate system in order to compensate for the degree of offset between the punching coordinates and the laser coordinates.

Description

Title: Procedure for offset dimension compensation

description

The invention relates to a method for detection and

Compensation of an offset between the punching coordinates of a punching device and the laser coordinates of a

Laser device in a combined punch-laser machine. The invention also relates to an associated one

Control device and an associated combined punch-laser machine. The invention also relates to a

Associated method for recognizing and compensating for an offset in a coordinate system of a

Processing machine for processing a workpiece, a Associated control device and an associated processing machine.

Combined punch-laser machines have proven themselves in recent years, in particular for the efficient processing of plate-shaped workpieces, in particular sheet metal.

Punch laser machines can take advantage of this

Stamping with the advantages of laser processing

combine. For example, standard contours and / or deformations, such as tabs or

Thread, by means of a punching head of the punching device

to be edited. On the other hand, for example

high-quality outer contours and / or filigree inner contours can be cut with the laser beam of the laser device.

Punch laser machines are especially used for that

Sheet metal processing used. In order to ensure an exact assignment of the laser to the punching process, the punch-laser offset is determined manually by a machine operator in combined punch-laser machines and then compensated by the machine operator through manual adjustment. This is comparatively complex and error-prone.

The punch-laser offset of a punch-laser machine can be different depending on the machine and can change for different reasons over the period of use. This is due to manufacturing tolerances of the machine elements, thermal expansion of the mechanics, collisions,

Manufacturing tolerances for different cutting heads, aging and any thermal expansion of the

processed workpieces over the processing time,

in particular due to the introduction of heat from the laser radiation. In other processing machines for processing a, in particular plate-shaped, workpiece

for example due to thermal expansion of the

processed workpieces over the processing time,

in particular due to a heat input during the

Machining, or due to a mechanical deformation during machining, result in an offset in the coordinate system of the processing machine.

The invention is therefore based on the object of enabling a simple and reliable way of determining and compensating for an offset in a processing machine. In particular, the invention is based on the object of ensuring a simpler and more reliable way of determining the punch-laser offset dimension and its compensation in a punch-laser machine.

This task is first carried out by a method with the

Features of claim 1 solved.

Accordingly, a method is proposed for the detection and compensation of an offset between the punching coordinates of a punching device and the laser coordinates of a

Laser device in a combined punch-laser machine for processing a plate-shaped workpiece, in particular a sheet metal, the method comprising the following steps: a. Introducing a structure into the plate-shaped workpiece by means of the punching device or by means of the

Laser device;

b. Determining a measured variable of the introduced structure by means of the laser device or by means of the

Punching device; c. Comparing the measured variable with an expected variable, a deviation of the measured variable from the expected variable corresponding to an offset; and

d. Calculating the offset with the coordinates of the

Laser device in the laser coordinate system or with the

Coordinates of the punching device in the punching coordinate system to determine the amount of offset between the punching coordinates and the

Compensate for laser coordinates.

The combined punch laser machine consequently has a

Punching device and a laser device.

According to the invention, a structure is introduced into the workpiece either by means of the punching device or by means of the laser device. The structure is consequently either punched or lasered.

A measured variable is then determined with the respective other device, that is to say either with the laser device or by means of the punching device. This measured variable is then compared with an expected variable. If the actually measured variable, i.e. the measured variable, deviates from the expected variable, the deviation corresponds to an offset between the laser coordinates in the laser coordinate system and the

Punch coordinates in the punch coordinate system.

The coordinates in the laser coordinate system and in the

Punching coordinate systems can already be compensated for by a previously known offset amount. One

misalignment determined according to the method

could therefore also be an error in the currently set

Offset measure are designated and around this error can then the coordinates of the laser device in Laser coordinate system or, alternatively, the coordinates of the punching device are compensated in the punching coordinate system. In other words: a determined offset represents a deviation by which the known and set offset between the laser and punching coordinates deviates from the actual offset between the laser and punching coordinates.

The punching coordinates in the punching coordinate system are programmed positions (X and Y position in

Coordinate system) on the workpiece at which a structure is to be punched into the workpiece by means of the punching device. The laser coordinates are accordingly programmed positions (X and Y positions in the coordinate system) on the workpiece, at which a structure is to be lasered, in particular cut, into the workpiece by means of the laser device.

If there is no offset between the punching device and

Laser device or accordingly between

Before punching operations on the workpiece and laser operations on the workpiece, the punching coordinate system and the laser coordinate system either have the same origin or, in particular, the origins are displaced by a known and correct offset relative to one another to the correct extent.

As already stated, there is usually an offset between the punching device and the laser device of a punch laser machine. Accordingly lies between

Stamping and laser processing regularly

Offset before. This offset can be different depending on the machine and in particular over the Change usage period. This can, for example, be due to manufacturing tolerances of the machine elements, to a

Thermal expansion of the mechanics, due to collisions

Manufacturing tolerances with different cutting heads, aging and thermal expansion of a

Workpiece during its machining. This

The offset can now be determined automatically according to the invention and corrected (after). The originally programmed position in the laser coordinates, at which a structure is to be introduced into the workpiece by means of the laser, is corrected by the offset. Alternatively, the originally programmed position could also be in the

Punch coordinates at which a structure is created using the

The punching device is to be introduced into the workpiece in order to correct the offset. Overall, compared to a manual determination and correction of the offset dimension, a significantly faster, simpler and less

error-prone determination and correction of the offset take place. Furthermore, due to the faster

Determine a determination and possible correction of the

Offset dimension can be carried out comparatively often without affecting the efficiency of the machining of the punch laser machine in a relevant manner.

An advantageous development of the invention provides that in step a. with the punching device or the

Laser device a breakthrough is made in the workpiece, wherein in step b. a clear breakthrough

descriptive point, especially the center of the

Breakthrough is determined by means of the laser device or by means of the punching device, wherein in step c. it is determined whether the position of the determined center point with the expected position of the center coincides, and wherein a deviation of the determined position from the expected position corresponds to an offset, and wherein in step d. In the event of a determined deviation of the actual center point from the expected center point, compensation of the offset dimension is carried out by calculating the offset dimension with the coordinates of the laser device in the laser coordinate system or with the coordinates of the punching device in the punching coordinate system in order to obtain the offset between the

Compensate punching coordinates and the laser coordinates.

In this case, the structure is consequently designed as a breakthrough. The measured variable is accordingly the center of the breakthrough. It is particularly conceivable that the opening is punched by means of the punching device and then the actual center point of the opening is determined by means of the laser device. However, the reverse is also conceivable.

It can then be determined whether the actual position of the center of the expected, programmed position

corresponds. A deviation corresponds to an offset and the coordinates of the laser device in the laser coordinate system can then be compensated for by this offset.

Another advantageous embodiment of the invention provides that the center point by emitting a

Detection light beam and based thereon detection of emitted or reflected light is determined.

This represents a particularly simple way of doing things

Offset measurement and correction. The center point is accordingly determined using an optical measuring method. The detection light beam can in particular be a

Be a laser light beam that is radiated onto the workpiece. Based on this, either process light emitted by the workpiece can then be detected, that is, the glowing of the hot workpiece due to the incident laser radiation. Additionally or alternatively, can also

reflected laser radiation can be determined. As long as the detection light beam is on the workpiece itself

can be a comparatively strong one

Detection light signal due to the emitted or

reflected light of the workpiece are detected. As soon as the breakthrough is reached, on the other hand, the strength of the detected signal collapses, since the detection light beam then shines through the breakthrough. In the opposite direction of travel, i.e. starting with the opening with

Direction of movement towards the workpiece, it behaves accordingly in reverse. Initially, no or a very low signal is detected. However, as soon as the detection light beam reaches the workpiece, a distinctive signal is detected. This way, the center of the

Breakthrough can be determined particularly easily. If the center point is determined by means of the laser device, the laser beam, which is otherwise used for processing the workpiece, can in this case be a corresponding one

Generate detection light beam. Such

Detection device is previously known, for example, from DE 10 2010 028 179 A1, the disclosure content of which is fully incorporated into the present application.

Alternatively, it is conceivable that a detection beam is emitted from a reflector below the workpiece is reflected. As soon as the workpiece interrupts this beam, the workpiece edge is reached.

With such a reflective light barrier configuration, the laser light is consequently reflected back in the break-through area via the reflector as long as the beam is not

Workpiece material meets. As soon as the beam reaches the workpiece, the beam is interrupted and the

Workpiece edge was recognized.

Finally, the detection of

transmitted laser light with the help of a photodiode underneath the workpiece. As long as the laser beam shines through the opening in the workpiece, the photodiode below the workpiece measures the laser radiation. If the laser beam is interrupted when the edge of the workpiece is touched, the signal measured by the photodiode underneath the sheet will also collapse.

If the center point is determined by means of the punching device, one provided on the punching head can be used for this purpose

Reflection light barrier or a punch breakage control sensor on the punching head can be used. Using the

Reflection light barrier or by means of the

Otherwise, the punch breakage control sensor can determine whether a punched-out structure has actually been removed from the workpiece. The retro-reflective sensor or the

Stamp breakage control sensors can in particular also generate a laser beam, with reflected or emitted

Detection light radiation can be detected for center point determination. Such a device is previously known, for example, from EP 2 878 393 A1, the disclosure content of which is also included in this application. Here, too, the process light of the workpiece can either be from a Reflector below the workpiece for reflected light or a signal from a photodiode below the workpiece

Midpoint determination can be used.

In this context, it is particularly advantageous if the opening is circular. The

Determination of the center point by moving the workpiece crosswise relative to the laser device or to the

Done punching device. Furthermore, the

Detection light beam are emitted by means of the laser device or by means of the punching device. In this way, the

Center can be determined. In order to move the workpiece relative to the laser device or the punching device, either only the workpiece or the

Laser device or the punching device are moved.

However, it would also be conceivable that both the workpiece and the laser device or the punching device are moved, for example along two axes offset by 90 °, in order to provide the relative displacement. Some punch laser machines have redundant axes with which the

Laser head can be displaced in a small area (highly dynamic), so that it is also conceivable that the laser device can be displaced crosswise relative to the workpiece.

It would be conceivable that the method is carried out as follows: First, an opening is punched in the workpiece. The workpiece is then displaced relative to the laser device in such a way that the detection laser beam passes through the

introduced breakthrough shines through. The detection laser beam is then displaced relative to the workpiece along a first straight line until the edge of the opening is achieved. The laser beam can then be shifted again along this first straight line in the opposite direction until the opposite edge is reached.

The laser beam can then be shifted by 90 ° along a second straight line until an edge is reached again and then finally in the opposite direction

Direction along the second straight line to this

opposite edge is reached. As a result, there is a cross-wise shift and it can be

Center of the breakthrough can be determined.

Alternatively, it could only be shifted once diagonally to the main axes of the punch laser machine in order to do so

to determine the actual center point.

It is particularly preferred if steps a. to d. be performed in multiple workpiece sections of the workpiece, with the offset amount for each

Workpiece section is determined, and the offset with the coordinates of the laser device in

Laser coordinate system in each workpiece section is calculated to the offset between the punching coordinates and the laser coordinates in the respective workpiece section

balance. The workpiece can consequently be divided into at least two, but in particular a multiplicity of workpiece sections. The workpiece sections can in particular be arranged regularly and have the same size. It is conceivable that the punch / laser offset dimension varies over the entire workpiece. By determining the

With the offset dimension in each workpiece section, the workpiece can be machined even more precisely by adding a corresponding local offset dimension in the corresponding Workpiece section is saved, stored and corrected in the workpiece section when it is processed accordingly.

Further it would be possible in areas between the

Workpiece sections for which the offset was determined between the respective determined offset

interpolate in order to achieve a particularly precise offset compensation in each area to be processed and still achieve a comparatively high process economy.

A method for detection and

Laser device in a combined punch-laser machine for processing a plate-shaped workpiece, in particular a sheet metal, the method comprising the following steps: a. Introducing one structure at a time into the

plate-shaped workpiece by means of the punching device and by means of the laser device;

b. Determination of measured variables of the introduced structures by means of the punching device or by means of the

Laser device;

c. Comparing the measured variables with expected variables, a deviation of the measured variables from the expected measured variables corresponding to an offset; and

d. Calculating the offset with the coordinates in

Laser coordinate system to measure the offset between the

Compensate punching coordinates and the laser coordinates. According to this proposal, a structure is consequently introduced into the plate-shaped workpiece by means of the punching device as well as by means of the laser device. The measured variables of the introduced structures can then either by means of the punching device or, in particular, by means of the

Laser device are determined. Based on this, the actual measured variables can be compared with expected measured variables, with a deviation corresponding to an offset measure, and the offset measure with the coordinates im

Laser coordinate system can be offset to a

Compensate for misalignment. This also enables the amount of offset to be determined comparatively quickly and easily

be performed. This is done in this case by

Introduction of one structure at a time using the

Punching device and the laser device, so that the punching processing introduced in this way with the laser processing

can be compared. The determination of the

Offset dimension in this case in particular by means of the

Punching device are carried out.

It is also particularly preferred if in step a. an opening is made in the workpiece with the punching device and with the laser device, wherein in step b. in each case a point clearly describing the openings, in particular the respective center point of the respective

Breakthrough is determined by means of the laser device or by means of the punching device, wherein in step c. it is determined whether the position of the determined center points to one another coincides with the expected position of the center points to one another, wherein a deviation of the determined position of the center points to one another corresponds to an offset, and in step d. in the event of a determined deviation in the actual location of the determined center points to each other from the expected position of the center points to each other a compensation of the offset dimension is carried out in that the offset dimension is offset against the coordinates of the laser device in the laser coordinate system in order to compensate for the offset dimension between the punching coordinates and the laser coordinates. Accordingly, two openings can first be made in the workpiece. The center points can then be determined and the actual position of the center points in relation to one another can be compared with the expected position of the center points in relation to one another. A deviation corresponds to an offset by which the coordinates in the laser coordinate system or in the punching coordinate system can finally be corrected.

The respective center point is advantageously through

Emission of a detection light beam and on it

based detection of emitted or reflected light from the workpiece. This represents a particularly simple way of determining and correcting the offset dimension. The respective center point is accordingly visualized

Measurement method determined. The detection light beam can in particular be a laser light beam which is radiated onto the workpiece. Based on this, either process light emitted by the workpiece can then be detected, that is, the glowing of the hot workpiece due to the incident laser radiation. In addition or as an alternative, reflected laser radiation can also be determined. As long as the detection light beam is on the workpiece itself

can be a comparatively strong one

Detection light signal due to the emitted or

reflected light of the workpiece are detected. As soon as the breakthrough is reached, the strength breaks of the detected signal, since the detection light beam then shines through the opening. In the opposite direction of travel, i.e. starting with the opening with

Direction of movement towards the workpiece, it behaves accordingly in reverse. Initially, no or a very low signal is detected. However, as soon as the detection light beam reaches the workpiece, a distinctive signal is detected.

This way the center of the breakthrough can be

can be determined particularly easily. If the center point is determined by means of the laser device, the

Laser beam, which is otherwise used to machine the workpiece, in this case a corresponding one

Generate detection light beam. Such

Alternatively, it is conceivable that a detection beam is emitted from a reflector below the workpiece

is reflected. Once the workpiece has this beam

interrupted, the workpiece edge is reached.

Workpiece edge was recognized.

Finally, the detection of

transmitted laser light with the help of a photodiode below of the workpiece. As long as the laser beam shines through the opening in the workpiece, the photodiode below the workpiece measures the laser radiation. If the laser beam is interrupted when the edge of the workpiece is touched, the signal measured by the photodiode underneath the sheet will also collapse.

Reflection light barrier or by means of the

Detection light radiation can be detected for center point determination. Such a device is previously known, for example, from EP 2 878 393 A1, the disclosure content of which is also included in this application. Here, too, the process light of the workpiece can either be from a

Reflector below the workpiece for reflected light or a signal from a photodiode below the workpiece

Edge detection can be used.

The openings are preferably circular. The determination of the respective center point can be made by moving the workpiece crosswise relative to the

Laser device or to the punching device. Furthermore, the detection light beam can be emitted by means of the laser device or by means of the punching device. In this way, the respective center point can be determined in a particularly simple manner. In order to move the workpiece relative to the laser device or to the punching device, either only the workpiece or the laser device or the punching device can be moved.

to determine the actual center point.

A particularly preferred development of the invention results from the fact that steps a. to d. be carried out in a plurality of workpiece sections of the workpiece, wherein the offset is determined for each workpiece section, and wherein the offset with the coordinates of the laser device in the laser coordinate system in each

Workpiece section is offset in order to compensate for the offset between the punching coordinates and the laser coordinates in the respective workpiece section. The workpiece can consequently in at least two, but in particular a plurality of

Workpiece sections are divided. The

Workpiece sections can in particular be arranged regularly and have the same size. It is conceivable that the punch laser offset dimension over the entire workpiece varies. By determining the offset in each workpiece section, the workpiece can be machined even more precisely by storing and storing a corresponding local offset in the corresponding workpiece section and, in the case of a corresponding machining, in the

Workpiece section is corrected.

Further it would be possible in areas between the

The object on which the invention is based is also achieved by a control device designed and set up to carry out an inventive method mentioned above

Procedure.

Finally, the object on which the invention is based is also achieved by a combined punch-laser machine, including the aforementioned one according to the invention

Control device.

A method is also proposed for recognizing and compensating for an offset of a coordinate system of a processing machine for machining a plate-shaped workpiece, in particular a sheet metal, the method comprising the following steps: a. Introducing a structure into the workpiece by means of the processing machine and determining a position of the

introduced structure in the coordinate system of

Processing machine by means of the processing machine; b. Processing the workpiece by means of the processing machine and, after a processing progress, again determining a position of the introduced structure in the coordinate system of the processing machine by means of the processing machine; c. Comparing the determined position with an expected position, a deviation of the determined position from the expected position corresponding to an offset; and d. Calculating the offset with the coordinates in

Coordinate system of the processing machine to compensate for the offset.

The offset corresponds to a change in position of the

introduced structure in the coordinate system of

Processing machine during the processing of the workpiece by means of the processing machine. The change in position can in particular the thermal expansion during the

Machining process or mechanical deformation during the machining process.

In the case of position change compensation, it is therefore a question of a change in the constitution of the workpiece

Any machining operations, for example due to heat and / or mechanical deformation, must be taken into account in the subsequent machining of the workpiece. The

Coordinates of the machining operations following an offset measurement and compensation according to the method are consequently corrected by the offset dimension. Overall, there can be an offset between the processing already introduced and the further processing to be introduced are compensated.

The structure can in particular be designed as an opening. Furthermore, the actual position of the center point of the opening with the expected position of the center point of the

Breakthrough can be compared. The center point can again be determined in a manner similar to that described above for the other proposals: Accordingly, the center point can through

Emission of a detection light beam and on it

based detection of emitted or reflected light of the workpiece can be determined.

This represents a particularly simple way of doing things

This represents the determination and correction of the offset dimension. The center point is therefore determined using an optical measuring method. Of the

Detection light beam can in particular be a

Laser light beam, emitted by the processing machine, which is radiated onto the workpiece. On the basis of this, either the emitted can be detected

Process light of the workpiece, that means the glowing of the hot workpiece due to the incident laser radiation. Additionally or alternatively, it can also be reflected

Laser radiation can be determined. As long as the

Detection light beam on the workpiece itself

can be a comparatively strong one

Detection light signal due to the emitted or

reflected light of the workpiece are detected. As soon as the breakthrough is reached, on the other hand, the strength of the detected signal collapses, since the detection light beam then shines through the breakthrough. In the opposite direction of travel, i.e. starting with the opening with Direction of movement towards the workpiece, it behaves accordingly in reverse. Initially, no or a very low signal is detected. However, as soon as the detection light beam reaches the workpiece, a distinctive signal is detected. This way, the center of the

Generate detection light beam. Such

is reflected. Once the workpiece has this beam

interrupted, the workpiece edge is reached.

With such a retro-reflective sensor configuration, the laser light is consequently reflected back in the break-through area via the reflector as long as the beam does not strike any workpiece material. On the other hand, as soon as the beam reaches the workpiece, the beam is interrupted and the edge is recognized.

Finally, the detection of

transmitted laser light with the help of a photodiode underneath the workpiece. As long as the laser beam shines through the opening in the workpiece, the photodiode below the workpiece measures the laser radiation. If the laser beam is interrupted when the edge of the workpiece is touched, the signal measured by the photodiode underneath the sheet will also collapse. In this context, it is particularly advantageous if the opening is circular. The

Determine the center point by moving the workpiece crosswise relative to the processing machine. Furthermore, the detection light beam by means of

Processing machine are broadcast. In this way, the center point can be determined in a particularly simple manner. To make the workpiece relative to

To move the processing machine, either only the workpiece or the processing machine can be moved. However, it would also be conceivable that both the workpiece and the processing machine are moved, for example along two axes offset by 90 °, in order to provide the relative displacement.

It would be conceivable that the method is carried out as follows: After a machining progress, the workpiece can be relocated relative to the machine tool that the

Detection laser beam shines through an introduced breakthrough. The detection laser beam is then displaced relative to the workpiece along a first straight line until the edge of the opening is reached. The

Laser beam in turn along this first straight line in

opposite direction until the

opposite edge is reached. The

The laser beam can be shifted offset by 90 ° along a second straight line until an edge is reached again and then finally in the opposite direction along the second straight line until the opposite edge is reached. As a result, there is a cross-wise shift overall instead and the center of the breakthrough can be determined.

Alternatively, it could only be shifted once diagonally to the main axes of the processing machine in order to achieve the

to determine the actual center point.

It is conceivable that the processing machine is designed as a punching or laser processing machine. In the case of a punching machine, mechanical deformation in particular can occur over the processing time of a workpiece, which leads to an offset which is corrected according to the invention.

In the case of a laser machine, thermal expansion can occur over the processing time of a workpiece due to the heat introduced, which leads to an offset which is corrected according to the invention.

The processing machine is advantageously as

combined punch-laser machine, with the

Coordinates of the laser device in the laser coordinate system and / or the coordinates of the punching device in the

Punching coordinate system with the determined offset

offset to compensate for the offset. Accordingly, in particular, an offset due to

Changes in the constitution of the workpiece, for example due to thermal expansion or mechanical deformation, are compensated for.

This has the following background: In the case of a workpiece, for example a sheet metal, the Punching operations carried out. The laser processing is then carried out regularly. For example be

Parts comprising individual punching processes are cut out one after the other by means of the laser. Because of the

Laser processing introduced into the workpiece, thermal expansion of the workpiece can occur. This results in a thermal expansion of the workpiece over the machining time and thus an offset by which the

actual position of the introduced structure in the workpiece deviates from the expected position. The laser coordinates in the laser coordinate system for the

subsequent laser processing can be corrected. It would also be conceivable, in particular if further punching operations are introduced into the workpiece, also to compensate the punching coordinates in the punching coordinate system in order to compensate for the offset.

A particularly preferred development of the invention results from the fact that steps a. to d. be carried out in a plurality of workpiece sections of the workpiece, wherein the offset is determined for each workpiece section, and the offset with the coordinates of the processing machine in each workpiece section

is offset by the offset in the respective

Compensate workpiece section. The workpiece can consequently in at least two, but in particular a plurality of

Workpiece sections are divided. The

Workpiece sections can in particular be arranged regularly and have the same size. It is conceivable that the offset varies over the entire workpiece. By determining the offset in each workpiece section, the workpiece can be machined even more precisely

take place by adding a corresponding local offset in the corresponding workpiece section is saved, stored and corrected in the workpiece section during a corresponding processing. A method is also proposed for recognizing and compensating for an offset dimension of a coordinate system of a processing machine for machining a, in particular plate-shaped, workpiece, in particular a sheet metal, the method comprising the following steps: a. Measuring the length and / or width of the workpiece, b. Processing of the workpiece by means of the processing machine and, after a processing progress, renewed determination of the length and / or width of the workpiece by means of the

Laser device; c. Determining a deviation of the determined length and / or width from the expected length and / or width, a deviation of the determined length and / or width from the expected length and / or width corresponding to an offset dimension, and d. Calculating the offset with the coordinates in

Coordinate system of the processing machine to compensate for the offset.

As a result, the length (X-axis) and / or the width (Y-axis) of the workpiece can first be measured.

After the processing progress, the length and / or width can then be measured again. The first measurement can take place before the start of the

Workpiece machining can be carried out. After the initial Machining of the workpiece can be started. After a certain processing progress, the length and / or width of the workpiece can then be measured again, in particular by measuring the recess, with a

Deviation in the actually measured length from the

expected length corresponds to an offset dimension that is specified in the coordinates in the machining machine coordinate system

can be compensated accordingly. A deviation in the length in the X direction corresponds to an offset in the X direction, while a deviation in the width in the Y direction corresponds to an offset in the Y direction.

After the offset dimension has been corrected, the further processing of the workpiece can consequently be carried out with a corrected offset dimension, so that despite an occurrence

Expansion of the workpiece, a sufficiently high machining accuracy can be achieved over the machining time.

The determination of the length or width can in particular again be carried out by means of an optical method. The length or width is therefore determined using an optical measuring method. The detection light beam can in particular be a laser light beam which is radiated onto the workpiece. Based on this, either process light emitted by the workpiece can then be detected, that is, the glowing of the hot workpiece due to the incident laser radiation. In addition or as an alternative, reflected laser radiation can also be determined. As long as the detection light beam is on the workpiece itself

can be a comparatively strong one

Detection light signal due to the emitted or reflected light of the workpiece are detected. In contrast, as soon as the end of the workpiece is reached, the strength of the detected signal collapses because the

The detection light beam then no longer shines on the workpiece. In this way, the center point, the length or the width can be determined particularly easily. In this case, a corresponding detection light beam can be generated by means of the laser beam, which is otherwise used for machining the workpiece. Such

is reflected. As long as the beam hits the workpiece, no or only a weak signal is detected.

With such a reflective light barrier configuration, however, the laser light is then transmitted via the reflector

reflected back when the beam is no longer on a

Workpiece material hits. As soon as the beam is the

Has reached the workpiece edge and strikes the reflector, the signal is immediately stronger so that reaching the workpiece edge and thus the length or width of the workpiece can be detected.

Finally, the detection of

transmitted laser light with the help of a photodiode underneath the workpiece. As long as the laser beam hits the workpiece, no signal is measured by the photodiode. As soon as the laser beam passes the workpiece edge, the beam hits the photodiode and a signal is detected. It is conceivable that in step b. only a partial length I ₂ and / or partial width is determined, and that in step c.

a deviation of the determined partial length I ₂ and / or

Section is determined from the expected part length I ₂ ^* and / or section. It is conceivable that future machining operations still have to be carried out in the area of these partial lengths or partial widths. By determining and compensating for the offset in these areas, particularly precise further processing can consequently be carried out.

It is also conceivable that the processing machine as

Stamping or laser processing machine is designed.

In the case of a punching machine, mechanical deformation, in particular, can occur over the processing time of a workpiece, which leads to an offset

is corrected according to the invention.

In the case of a laser machine, thermal expansion in particular can occur over the processing time of a workpiece, which leads to an offset that is according to the invention

is corrected.

It is also conceivable that the processing machine as

combined punch-laser machine is formed, the coordinates of the laser device in the laser coordinate system and / or the coordinates of the punching device in the

Punching coordinate system with the determined offset

offset to compensate for the offset. The length (in the X-axis direction) and / or the width (in the Y-axis direction) of the workpiece can consequently first be measured.

After the processing progress, the length and / or width can then be measured again. The first measurement can in particular before or after

Punching, but at least before

Laser machining of the workpiece. The workpiece can then be laser processed. After a certain processing progress, the length and / or width can then be measured again, with one

The deviation in the actually measured length and / or width from the expected length and / or width corresponds to an offset that can be compensated for in the coordinates in the laser coordinate system. A deviation in the length in the X direction corresponds to an offset in the X direction, while a deviation in the width in the Y direction corresponds to an offset in the Y direction.

After the offset dimension has been corrected, the further laser processing of the workpiece can consequently be carried out with a corrected offset dimension, so that despite any

Thermal expansion of the workpiece due to the laser processing, a sufficiently high processing accuracy can be achieved over the processing time.

It is conceivable that, after the initial measurement of the length, all of the punching operations are first introduced into the workpiece. The laser processing can then be carried out. The laser processing can, for example, initially in the X direction in a first part of the workpiece respectively. After a certain processing progress, for example when 2/3 of the processing has been carried out in the X direction, the length of the recess in the last third of the workpiece can be measured. If there is a difference to the original length of the last third of the recess, this corresponds to a

Offset dimension in the X direction, which is used for the remaining

Machining of the last third of the workpiece can be corrected.

The problem on which the invention is based is also solved by a control device designed and set up to carry out one of the aforementioned methods.

The problem on which the invention is based is finally also solved by a processing machine, in particular a combined punch-laser machine, laser machine or

A punching machine, comprising an aforementioned control device according to the invention.

Further details and advantageous embodiments of the invention can be found in the following description, on the basis of which the embodiments of the invention shown in the figures are described and explained in more detail.

Show it:

Figure 1 perspective view of a combined

Punch laser machine; FIG. 2 shows a schematic representation of a method for recognizing and compensating for a punch laser offset dimension according to a first embodiment;

Figure 3 schematic representation of a method for

Detection and compensation of a punch laser offset dimension according to a second

Embodiment; and

Figure 4 a) to e) schematic representation of a

Method for the detection and compensation of a punch laser offset dimension according to a third embodiment.

In Figure 1 is schematically an embodiment of a

combined punch laser machine 1 shown with the a

Workpiece 14, for example in the form of a sheet metal, can be punched both by means of punching processing and also processed by means of laser processing, in particular cut. A component of the processing machine 1 is a C-frame 2. The C-frame 2 consists of a torsionally rigid welded construction made of steel. The C-frame 2 can, however, also have a different shape. A control device 3 for controlling the functions of the processing machine 1 is provided at the rear end of the C-frame 2.

At the front inner end of the upper leg of the C-frame 2, the processing machine 1 has a punching device 17 with an upper tool holder 4 and a lower one

Tool holder 5 at the front inner end of the lower

Legs of the C-frame 2. An upper tool part of a punching tool 7 can be received in the upper tool holder 4 and a lower tool part of the punching tool 7 can be accommodated in the lower tool holder 5.

The upper tool holder 4 can be moved in an axial direction (Z-direction) by means of a plunger (not shown) and is controlled with the aid of the control device 3 so that it can both perform a complete stroke and stop in any position within its axial stroke . Furthermore, the upper tool holder 4, controlled by the control device 3, can optionally be rotated about an axial axis of rotation 6.

The lower tool holder 5 can optionally also be rotated about its axis of rotation 6. Furthermore is the lower one

Tool holder 5 immovable in its axial direction (Z direction), but can optionally also be designed as a so-called active die. Then it can also be moved in its axial direction as well as through the

Control device 3 controlled, in any

Stop the position of its axial stroke.

In addition to the upper tool holder 4 and the lower one

Tool holder 5, the processing machine 1 also has a laser processing device 8 with a laser processing head 16 with which, for example, the workpiece 14 can be processed, in particular cut. In a workpiece table 9 on the inner side of the lower leg of the C-frame 2, a circular opening 10 is provided. Of the

Laser processing head 16 can be moved by means of a movement unit (not shown) in an X direction and in a Y direction and, in order to set a suitable focus position, in the Z direction. The circular opening 10 sets in Essentially a processing area 11 of the

Laser processing head 16 fixed.

The workpiece table 9 has a cross rail 12 with a

Tool magazine up. Clamping claws 13 for holding the workpiece 14, which can in particular be in the form of a sheet metal plate, are arranged on the cross rail 12. The

Clamping claws 13 can be in suitable places on the

Cross rail 12 are attached, and can be moved so that the sheet metal plate 14 is securely held, but the sheet metal plate 14 is not on a surface to be processed

is grasped. In the tool magazine there are several, here three, tool holders 15 for several, here two,

Stamping tools 7 shown.

In operation, the workpiece table 9 can be punched in a Y direction together with the cross rail 12 on which the

Clamping claws 13 are attached, with which the workpiece 14 is held, can be moved into a programmed position. In the same way, the cross rail 12 can be moved in the X direction into the programmed position

Workpiece 14 slides over the workpiece table 9. A punching stroke can then be carried out from the upper tool holder 4. The next punching position can then be approached using the same principle. After the same

In principle, the workpiece 14 can be moved to a programmed position in order to carry out laser processing by means of the laser processing machine 8.

In order to now process a workpiece is regular

The procedure is as follows: First, at programmed positions on the workpiece 14 by means of the punching device 17 punching operations introduced. The positions for the punching operations are in one place as coordinates

Punching coordinate system stored. Thereupon 8 laser machining operations can be performed by means of the laser machining device

be performed. Individual parts that have been punched are regularly cut out of the workpiece 14 with laser cuts. The laser processing is also carried out at the programmed positions of the

Workpiece, which are stored in a laser coordinate system, performed.

If there is no offset between the punching coordinate system and the laser coordinate system, a point on the workpiece 14 has the same in both coordinate systems

Coordinates on. However, there is regularly an offset between the two coordinate systems. This offset can be different depending on the machine and can change in particular over the period of use of the combined punch-laser machine 1. This is due, for example, to manufacturing tolerances of the machine elements, thermal expansion of the mechanics, collisions, manufacturing tolerances

different cutting heads, aging as well as one

thermal expansion of the workpiece 14 during the

Machining, especially during laser machining. The resulting punch-laser offset can be saved as an offset, with the coordinates in

The laser coordinate system can be offset against the offset so that the laser processing actually takes place on the

desired location in the workpiece 14 can be carried out.

In the following three embodiments of a method for the automatic detection and compensation of a Offset between the punching coordinates of the

Punching device 17 and the laser coordinates of

Laser device 8 outlined:

Figure 2 shows a first embodiment of the method. If it has been decided that the offset should be determined or whether an offset that has already been stored is still correct, a circular opening 19, that is, a hole, is punched at a defined point on the workpiece 14. Alternatively, such a hole could be used which is already present in the workpiece 14 as a punching process. The laser processing head 16 is then moved over the hole 19 produced in the workpiece 14. A laser beam 18 is then generated with the laser device 8. If the laser beam 18 is used to direct laser radiation onto the workpiece 14, this is the case

Workpiece 14 is hot, so that this process light 24 emits. This process light 24 can be detected. Thus can

it can be determined whether the laser radiation 18 is incident on the workpiece 14. When the laser beam 18 shines onto the hole 19, at least almost no process light 24 occurs and the signal from the process light 24 collapses. A

Laser processing device 8 with a detection device for determining the intensity of the process light 24 is already known from DE 10 2010 028 179 A1

Revelation content with in the revelation content of

present application is included. The

The laser processing device 8 accordingly has such an evaluation device.

The laser beam 18 is then first moved in an X direction 35, specifically until the signal intensity 37 of the detected process light rises and a defined one Exceeds threshold. The

proceed in the opposite direction, again until the

Light intensity increases. An increase in the light intensity indicates that the edge 20, 21 of the hole 19 has been reached. The laser beam 18 is then moved in the Y direction 39 until the edge 22 of the hole 19 is reached and finally in the opposite direction again until the edge 23 of the hole 19 is reached. Overall, from the thus determined

Coordinates of the edges 20, 21, 22, 23 of the center m of the hole 19 can be determined.

The center m determined in this way points in

Laser coordinate system the actual coordinates of the center point m on the workpiece 14. This center point m is then compared with the expected coordinates of the expected center point m *. This expected center point m * has coordinates in the laser coordinate system that indicate the expected position of the center point without (correct)

Represent offset dimension compensation. In the case shown in FIG. 2, there is a not yet corrected offset between the punching coordinates and the laser coordinates in the X direction by an offset DC and in the Y direction by a

Offset dimension DU. The

programmed coordinates in the laser coordinate system are now (post-) corrected in the X and Y directions, so that the laser processing by means of the laser beam 18 is exactly where the actual

desired location on the workpiece 14 is performed.

FIG. 3 shows a second embodiment for determining the punch laser offset. First, a hole 25 is punched in the workpiece 14 by means of the punching device 17. In addition, a hole is made with the laser processing device 8 26 cut. The amount of offset between the two holes can then be determined by means of a detection device (not shown) arranged on the punching device 17. Such a detection device is previously known from EP 2 878 393 A1, for example

Disclosure content is fully incorporated into the disclosure content of the present patent application.

The procedure then proceeds as follows: The

The detection device in the punching device 17 has means for directing a laser beam onto the workpiece 14, as well as means for detecting the process light emitted by the workpiece or reflected laser light. The actual position of the respective center point is determined, as explained above for FIG. 2, by moving the laser beam crosswise and determining the signal intensity. The detected radiation intensity collapses when the laser beam is in the area of hole 25 or hole 26. Overall, a deviation of the position of the actual center points from the expected position of the center points in

Punching coordinate system determined. In the embodiment shown in Figure 3, the determination is made by means of

Detection device of the punching device 17 carried out. Consequently, the center ml of the hole 25 also lies where it is expected. However, the center m2 of the hole 26 lies on different coordinates than expected. The center would have been expected at the coordinates of position m *. This means that there is a not yet corrected offset dimension DC in the X direction or DU in the Y direction. The coordinates in the laser coordinate system can be (post-) corrected by this offset in order to compensate for the offset. FIG. 4a shows a workpiece 14 which is arranged on clamping claws 13, as described above. Along the length 27 of the workpiece 14 in the X direction, the

Laser radiation 18 of the laser processing device 8 determines the length li of the workpiece 14 in the X direction by again analyzing when the intensity of the reflected

Radiation or the detected process light collapses.

In a next step, as indicated in FIG. 4b, punching operations in the form of holes 28, 29 lying next to one another, which are repeatedly made in the workpiece 14, are introduced into the workpiece 14. Then, as shown in FIG. 4c, the workpiece 14 is laser machined, with a laser cut 30 around a pair of the holes 28,

29 is carried out, so that a workpiece part 31 is detached from the workpiece 14. In the course of this processing, heat is introduced into the workpiece 14, which

can be designed in particular as sheet metal instead. This causes the workpiece 14 to expand. This in turn results in a not yet corrected offset dimension between the

Punch coordinates and the laser coordinates, which are determined and corrected using the following procedure:

As shown in FIG. 4b, the last section of the workpiece 14 has not yet been processed by means of laser processing. By means of the laser cutting machine 8, the last part of the workpiece 14 is traversed from the starting point 32 until the edge 33 is reached at which the detected light signal

collapses, with a laser beam being directed onto the workpiece 14. On the basis of the previous measurement, a length I2 * was expected for this between the starting point 32 and the expected end point 33 * of the workpiece 14. Due to of the thermal expansion, however, the actual end point is at position 33, so that an actual length I2 is measured. In this respect, there is a difference between position 33 and position 33 * in the X direction. This difference represents a not yet corrected offset dimension DC. The coordinates in the

Laser coordinate system (post-) corrected. As a result, as shown in FIG. 4e, the laser cut 30 can take place

Coordinates are carried out in the laser coordinate system, which are (post-) corrected by the offset DC, so that a sufficient manufacturing accuracy of the workpiece parts 31 is also given towards the end of the cutting process.

The embodiment according to FIG. 4 can also be used with others

Processing machines are used. Would be conceivable

for example an offset compensation in pure

Punching machines or laser machines. With such

Processing machines can over the processing time of a workpiece due to thermal expansion, especially in the case of laser machines, and / or mechanical deformation,

In particular in the case of punching machines, a (not yet corrected) offset may occur which can be detected and compensated for using the procedure shown in FIG. In the case of punching machines, a detection device can be provided to determine the offset, which a

Includes laser beam source.

Overall, according to the invention, automatic detection and compensation of the punch-laser offset dimension can be implemented in one

combined punch laser machine 1 can be carried out. This eliminates the error-prone and time-consuming manual determination and compensation of the offset. Of course it could however, manual measurement and correction can be carried out in redundancy for the automatic measurement and correction according to the invention. According to the embodiment of Figure 4, a,

for example, heat or deformation-related,

Change of constitution of a workpiece during this

Processing in other processing machines, such as pure punching machines or laser machines, can be compensated.

Claims

1. Procedure for detection and compensation of a

Offset between the punching coordinates of a

Punching device (17) and the laser coordinates of a laser device (8) in a combined punch-laser machine (1) for processing a plate-shaped

Workpiece (14), in particular a sheet metal that

A method comprising the following steps: a. Introducing a structure (19) into the plate-shaped workpiece (14) by means of the punching device (17) or by means of the laser device (8); b. Determining a measured variable of the introduced structure (19, 25, 26) by means of the laser device (8) or by means of the punching device (17); c. Comparing the measured variable with an expected variable, a deviation of the measured variable from the expected variable corresponding to an offset; and d. Calculating the offset with the coordinates of the laser device (8) in the laser coordinate system or with the coordinates of the punching device (17) in

Punch coordinate system, around the amount of offset between the punch coordinates and the laser coordinates

balance.

2. The method of claim 1, wherein in step a. an opening (19) is made in the workpiece (14) with the punching device (17) or the laser device (8), wherein in step b. a clear breakthrough Descriptive point, in particular the center point (m) of the opening, is determined by means of the laser device (8) or by means of the punching device (17), wherein in step c. it is determined whether the location of the

determined center point (m) coincides with the expected position of the center point (m *), and where a

The deviation of the determined position from the expected position corresponds to an offset dimension, and in step d. if there is a deviation from the actual one

Center (m) from the expected center (m *) a compensation of the offset is carried out by calculating the offset with the coordinates of the laser device (8) in the laser coordinate system or with the coordinates of the punching device (17) in the punching coordinate system in order to determine the offset between the

Compensate punching coordinates and the laser coordinates.

3. The method according to claim 2, wherein the center point (m)

is determined by emitting a detection light beam and based thereon detection of transmitted, emitted or reflected light.

4. The method according to claim 3, wherein the breakthrough (19)

is circular, the determination of the center point by moving the workpiece crosswise

(14) relative to the laser device (8) or to

Punching device (17) takes place, the

Detection light beam is emitted by means of the laser device (8) or by means of the punching device (17).

5. The method according to any one of the preceding claims, wherein the steps a. to d. according to one of the preceding Claims are carried out in several workpiece sections of the workpiece (14), wherein the

Offset dimension is determined for each workpiece section, and the offset dimension with the coordinates of the

Laser device (8) in the laser coordinate system or with the coordinates of the punching device (17) in

Punching coordinate system in each workpiece section is calculated to the offset between the

Compensate punching coordinates and the laser coordinates in the respective workpiece section.

6. Procedure for detection and compensation of a

Offset between the punching coordinates of a

Workpiece (14), in particular a sheet metal that

A method comprising the following steps: a. Introduction of one structure (25, 26) in each case into the plate-shaped workpiece (14) by means of the

Punching device (17) and by means of the laser device (8); b. Determining measured variables of the introduced structures (25, 26) by means of the punching device (17) or by means of the laser device (8); c. Compare the measured variables with an expected variable, with a deviation of the measured variables from the

expected measured variables corresponds to an offset measure; and d. Calculating the offset with the coordinates of the laser device (8) in the laser coordinate system or with the coordinates of the punching device (17) in

balance.

7. The method of claim 6, wherein in step a. with the punching device (17) and with the laser device (8) an opening (25, 26) is made in the workpiece (14), wherein in step b. in each case a point clearly describing the breakthroughs, in particular the respective center point (ml, m2) of the respective

Opening (25, 26) is determined by means of the laser device (8) or by means of the punching device (17), wherein in step c. it is determined whether the position of the determined center points (ml, m2) to one another corresponds to the expected position of the center points (ml, m2) to one another, with a deviation of the determined position of the center points (ml, m2) to one another

Offset, and where in step d. if the actual position of the determined center points (ml, m2) to one another deviates from the expected position of the center points (ml, m2) to one another, the offset dimension is compensated for by comparing the offset dimension with the coordinates of

Punching coordinate system is calculated to the

Offset between the punching coordinates and the

Compensate for laser coordinates.

8. The method of claim 7, wherein the respective

Center point (ml, m2) by emitting a

Detection light beam and detection based on it of transmitted, emitted or reflected light is determined.

9. The method according to claim 8, wherein the openings (25,

26) are circular, and where the

The respective center point (ml, m2) is determined by moving the workpiece (14) crosswise relative to the laser device (8) or to the punching device (17), the detection light beam being emitted by means of the laser device (8) or by means of the punching device (17).

10. The method according to any one of claims 6 to 9, wherein steps a. to d. according to one of the preceding

Claims 6 to 9 are carried out in several workpiece sections of the workpiece (14), wherein the

11. Procedure for the detection and compensation of a

Offset dimension of a coordinate system of a

Processing machine for processing a, in particular plate-shaped, workpiece (14), in particular a sheet metal, the method comprising the following steps: a. Introducing a structure into the workpiece (14)

by means of the processing machine; b. Processing of the workpiece (14) by means of

Processing machine and after one

Processing progress Determination of a position of the introduced structure in the coordinate system of the processing machine by means of the processing machine; c. Comparing the determined position with an expected position, a deviation of the determined position from the expected position corresponding to an offset; and d. Calculating the offset with the coordinates in

Coordinate system of the processing machine to compensate for the offset.

12. The method of claim 11, wherein the

Processing machine as a punching or

Laser processing machine is designed.

13. The method of claim 11, wherein the

Processing machine is designed as a combined punch-laser machine, the coordinates of the laser device (8) in the laser coordinate system and / or the coordinates of the punching device (17) in the

The punching coordinate system must be offset against the determined offset in order to compensate for the offset.

14. Procedure for detection and compensation of a

Offset dimension of a coordinate system of a

Processing machine for processing a, in particular plate-shaped, workpiece (14), in particular a sheet metal, the method comprising the following steps: a. Measuring the length and / or width of the workpiece (14), b. Processing of the workpiece (14) by means of

Processing machine and after one

Processing progress again determining the length and / or width of the workpiece (14) by means of the

Processing machine; c. Determining a deviation of the determined length and / or width from the expected length and / or width, wherein a deviation of the determined length and / or width from the expected length and / or width corresponds to an offset; and d. Calculating the offset with the coordinates in

Coordinate system of the processing machine to the

Compensate for misalignment.

15. The method of claim 14, wherein in step b.

only a partial length (I2) and / or partial width is determined, and wherein in step c. a deviation of the determined part length (I2) and / or part width from the expected part length (I2 *) and / or part width is determined.

16. The method of claim 14 or 15, wherein the

Processing machine as a punching or

Laser processing machine is designed.

17. The method of claim 14 or 15, wherein the

18. Control device (3) designed and set up to carry out a method according to one of the

Claims 1 to 10.

19. Combined punch-laser machine (1), comprising a control device according to claim 18.

20. Control device (3), designed and set up to carry out a method according to one of

Claims 11 to 17.

21. Processing machine, in particular combined punch-laser machine (1), laser machine or punching machine, comprising a control device according to claim 20