EP3245475A1

EP3245475A1 - Measuring system and method for calibrating printing stations

Info

Publication number: EP3245475A1
Application number: EP15813082.3A
Authority: EP
Inventors: Markus Reiniger; Sascha Koers; Katrin Preckel; Daniel Teufert; Werner Van De Wynckel
Original assignee: KHS GmbH
Current assignee: KHS GmbH
Priority date: 2015-01-12
Filing date: 2015-12-21
Publication date: 2017-11-22
Also published as: US10336109B2; DE102015100337A1; US20180009246A1; WO2016113086A1

Abstract

The invention relates to a measuring system for measuring a printing station (3) comprising a printing head (2). Said printing head (2) can be held in its position and can be adjusted on the printing station (3). The measuring system (10) comprises the following: at least one measuring device (11) which is designed to detect measuring information of a position-modifiable component of the printing station (3) during the movement thereof; a calculating unit (12) which is designed to capture the measurement information provided by the measuring device (11), said calculation unit (12) being designed to determine the actual positional information of the position-modifiable component from the captured measuring information, for comparing said actual positional data to predetermined desired positional data and for determining calibration information based on the actual positional data and the desired positional data; an interface (13) for transmitting the calibration information.

Description

Measuring system and method for calibrating printing stations

The invention relates to a measuring system according to the preamble

Claim 1 and to a method for calibration of printing stations according to the preamble of claim 12.

Devices for printing containers are known in different designs. In particular, printing systems for printing on containers using digital ink jet or ink jet printing heads are known. In particular, are also known

Printing systems or printing presses (for example, DE 10 2007 050 490 A1), in which they are driven in rotation on at least one vertical axis

Transport element a plurality of treatment or printing stations are formed for receiving a respective container to be printed on which the container under

Use of electronically controllable, operated on the inkjet or ink-jet principle, digital printheads are printed.

An essential factor for optically high-quality printing of containers is the most exact alignment of the print head relative to the container to be printed. In this case, the calibration of the printhead within the respective printing station is of decisive importance.

From the document DE 10 2012 005 046 A1 a method for detecting errors in the alignment of printed images has become known. In this case, at least two print heads are assigned to the respective print head

Print image generated. Subsequently, the printed images are optically detected and evaluated by means of image processing means in order to determine a deviation of the printed images of the at least two print heads to their nominal arrangement. A disadvantage of the known method is that of different

Override alignment errors of the print head caused alignment errors, so that often insufficient conclusions can be drawn on to be made alignment corrections of the print head. Proceeding from this, it is an object of the invention to provide a measuring system by means of the highly accurate and time-saving measurement and calibration of the at least one print head of the printing station is possible.

The object is achieved on the basis of the preamble of independent claim 1 by its characterizing features. A method for calibrating printing stations is the subject matter of the independent patent claim 12. According to a first aspect, the invention relates to a measuring system for measuring a printing station having a printing head. The printhead is adjustable in position, in particular held by a motor adjustable at the printing station. In this context, "adjustable" in the sense of the invention means, in particular, a translatory movement or a displacement in at least one, preferably in a plurality of spatial directions and / or a pivotability about at least one pivot axis. transmission) interface.

The measuring device is designed in particular for detecting measurement information of a positionally variable component of the printing station during its movement. The positionally variable component may in particular be the print head itself, but also the positionally variable print head carrier on which the print head is held. The measuring device is connected to the computer unit for the transmission of

Coupled with measurement information. The computer unit is designed to receive the measurement information provided by the measuring device, i. has a suitable interface, which is connected to an interface of the measuring device. The computer unit is for determining actual position data of

position-variable component from the received measurement information, for comparing these actual position data with predetermined desired position data and for determining calibration information based on the actual position data and the desired position data formed. The nominal position data are included Position information indicating a desired position or a desired trajectory of the position-variable component. They can be stored, for example, in a storage unit connected to the computer unit. This storage unit can be the measuring system, but also the respective printing station or these

Be assigned printing station having printing device (central storage unit). The calibration information determined in this way is provided at the (transmission) interface and can then be suitably reused.

For example, these can be assigned to one of the respective printing station

Memory unit are transmitted in order to calibrate by accessing this memory unit, the at least one printhead this print station can. Alternatively, the calibration information can also be transmitted to a central storage unit assigned to the printing device. Moreover, it is possible the

To connect print station directly to the measuring system via the (transmission) interface to perform a direct calibration of the at least one printhead this print station.

The main advantage of the measuring system is that the print head can be calibrated very accurately and quickly to a defined target position, without any conclusions about a printed image of a printed container.

According to one embodiment, the measuring device is designed to determine three-dimensional measurement information. This allows an accurate recording of the actual position of the print head in three-dimensional space. According to one embodiment, the measuring device is a camera,

preferably a 3D camera or a laser scanner, preferably an SD laser scanner. By means of these measuring devices, measurement information relating to the surfaces of the positionally variable component in the printing station can be determined, which contains information about the local position, in particular the three-dimensional position of the positionally variable component. Based on this

Measurement information position correction quantities can be determined as calibration information. According to one embodiment, the positionally variable component is the print head carrier or a defined region of the print head carrier or a region of the print head. The print head carrier can be, for example, a print head holder which can be displaced in different spatial directions and / or a print head holder which can be swiveled about at least one pivot axis. By recording measurement information on the printhead carrier or on the printhead itself can be used to determine the

Calibration information necessary measurement information can be obtained.

According to one embodiment, the positionally variable component is at least one printhead nozzle. The printhead nozzle represents the delivery point of the ink or printing ink and thus forms an ideal, from the measuring device to

measuring point. By using the print head nozzle as the measurement point to be detected, optimized print head calibration can be achieved. According to one embodiment, the positionally variable component is at least one reference surface of the print head. Depending on the printhead type used, an area can be provided, for example, on the housing of the printhead or in the area of the printhead nozzles, which can be used as the reference area to be detected in order to determine the actual position data from the measurement information.

According to one embodiment, the print station is a replaceable one

Printing module, wherein the measuring system for registration alignment and / or

Holder and measurement of this pressure module is formed. For example, the measuring system has a receptacle or a stop for the printing module, so that the printing module in the disassembled state, i. detached from the rotor or the support element to which the pressure module in the installed state at the

Pressure device is attached, can be measured. This ensures that a predetermined alignment between the measuring device and the

measuring position variable component is achieved.

According to one exemplary embodiment, the interface is designed for coupling to a memory unit provided in the printing station or in the printing module and for transmitting the calibration information to this memory unit. In the event that the printing station is designed as an exchangeable printing module, can the measurement of the printing module can be measured after its first production or after an inspection at the manufacturer. The calibration information can then be stored in the memory unit. After the installation of the printing module in the printing device, a calibration of the printing module can then be carried out on the basis of the calibration information. Furthermore, it is possible that the printing station or the printing module is recalibrated, for example, at certain intervals on the basis of the calibration information.

Alternatively, it is possible that the interface is designed for coupling to a central storage unit connected to a multiplicity of printing stations and for transmitting the calibration information to this storage unit. Thus, the calibration information of all printing stations of a printing device can be stored centrally, wherein an assignment of the calibration information has to be made to a defined printing station, for example by an identifier or an addressing. For calibration purposes, the calibration information can then be read out and the printing stations can be assigned according to their assigned

Calibration information to be calibrated.

According to one embodiment, the computer unit for determining

Calibration information is formed, the movement information for the

position-variable component for calibrating the same to a desired position. For example, the calibration information may indicate the direction of movement and the amount of movement required to move from an actual position to a desired position. For this purpose, one or more encoders can be provided on the mechanism moving the print head, by means of which either an absolute position (absolute encoder) or a relative position (relative to a reference point, for example a reference mark or an end position) can be determined. This allows the printhead to be moved exactly to a desired setpoint position. Other positioning methods known from the prior art are also possible.

According to one embodiment, means are provided for the exact positioning and / or alignment of the measuring device relative to the printing station. Such means may be, for example, optical means, which by detecting a Reference surface or other defined area of the printing station allow a desired orientation of the measuring device relative to the printing station. Also mechanical alignment means are conceivable. This calibration inaccuracies can be minimized.

In another aspect, the invention relates to a method of calibrating print stations having a printhead comprising the steps of:

- Providing a measuring device for the detection of

Measurement information of a positionally variable component of

Print station is formed;

- Moving the position-variable component relative to

Measuring device;

- Acquire measurement information during the movement of the

position-variable component by the measuring device;

- Transferring the measurement information to a computer unit or a corresponding data storage unit;

- determining actual position data from the measurement information;

- Determining calibration information from the actual position data and predetermined desired position data;

- Calibrate the printhead based on the calibration information.

Data storage can work on different systems and on

done in different places. In particular, the measurement information is stored in a memory unit of the print module itself, so that this measurement and calibration information is always available temporally and spatially together with the respective print module. Thus, each printing module brings with it its own, unique characteristic of its own geometry and tolerance deviation when connecting or during installation at the intended location (printing station or printing device).

In a particularly advantageous embodiment, the printing module or the printing station has a port or recording option and data interface for removable, portable storage medium, such as a USB flash drive (USB flash drive), micro SD card, a USB security dongle or the like. The measurement and calibration data are then stored on these removable storage media, which may also be stored, secured and / or shipped separately from the print modules or stations.

Thus, a print module can not be accessed without the associated portable

Storage medium to be put into operation. On the portable storage medium, in addition to the measurement and calibration data, advantageously further suitable data in particular are stored for the print module and / or the print station.

In a variant of this, the measurement and calibration data for a number of printing modules or stations are stored on only one of the portable storage media, wherein only a printing module, a printing station or the printing device itself has a recording facility and interface for this storage medium.

The data transfer from the measuring system to the portable memory is carried out in a known manner directly on the measuring system or downstream of a central control and computer unit.

Of course, the measured values can be stored and provided solely or additionally in the control or storage unit of the printing device, the printing stations or on a central server, here in particular also in an online cloud. An online storage space offers esp. The advantages that easy availability of the data is given, which is advantageous in addition to the installation of modules for batch tracking and quality management.

The main advantage of the method according to the invention is that the print head can be calibrated very accurately and quickly by measuring at least one positionally variable component to a defined desired position, without any conclusions about a printed image of a printed container. According to one embodiment, the position-variable component is moved during acquisition of the measurement information at least in two, preferably three independent spatial directions and / or by at least one

Swivel axis pivots. This makes it possible to record measurement information containing information about the trajectory of the position-variable component. This can advantageously a more accurate calibration of

Printing station to be made.

According to one embodiment, measurement information of a

Printhead support and / or a region of the printhead, in particular at least one printhead nozzle or a reference surface of the printhead won.

According to one embodiment, the calibration method becomes two-stage

performed, wherein in a first measuring step, first a set of

Measurement information regarding the moving printhead support and in a second measuring step, a set of measurement information with respect to a range of the moving printhead, in particular at least one printhead nozzle or a reference surface of the printhead is determined. Based on the measurement information determined in the first and second measurement steps, the

Calibration information determined. This allows a more accurate calibration information obtained and thus a more accurate calibration of the printing station can be achieved. In addition, it is possible to reuse the measurement information obtained in the first measurement step during a printhead change, so that only the second measurement step has to be performed again.

According to one embodiment, the printing station is calibrated directly by the determined calibration information. That the won

Calibration information is transmitted via the interface of the measuring system directly to the printing station and there is a direct calibration of the

Print station based on this calibration information.

Alternatively, it is possible for the calibration information to be stored in a central memory unit provided for a plurality of print stations and for the each print station is calibrated after transmission of Kalibrie nformationen to this printing station on the basis of this Kalib erinformationen.

Furthermore, it is alternatively possible for the calibration information to be stored in a memory unit provided in the respective print station and for the print station to be calibrated using this calibration information stored in the memory unit. This makes it possible that, for example, in the case of a replaceable printing station designed as a printing module, the measurement and determination of the calibration information is carried out spatially and temporally separate from the actual calibration of the printing station, wherein, for example, the measurement is carried out by the manufacturer or a maintenance company for the printing stations and the calibration is performed only after the installation of the printing station in the printing device. When storing the calibration information in a central or the respective printing station associated storage unit, it is possible that the printing station at certain intervals or when determining the need for a

Recalibration is recalibrated based on the stored calibration information.

Under container in the context of the invention, all containers are understood, especially bottles, cans, etc.

The expression "essentially" or "approximately" in the sense of the invention means deviations from the exact value by +/- 10%, preferably by +/- 5% and / or deviations in the form of changes that are insignificant for the function.

Further developments, advantages and applications of the invention will become apparent from the following description of exemplary embodiments and from the figures. In this case, all described and / or illustrated features alone or in any combination, in principle, the subject of the invention, regardless of their summary in the claims or their Dependency. Also, the content of the claims is made an integral part of the description.

The invention will be explained in more detail below with reference to the figures of exemplary embodiments. In the drawings: By way of example, a printing device in a schematic plan view; 2 shows by way of example a printing station to be arranged on the printing device as a printing module in a perspective view;

3 shows by way of example an arrangement of a measuring system in front of a printing station in a schematic plan view; and

4 shows by way of example an arrangement of a measuring system in front of a rotor comprising a plurality of printing stations in a schematic plan view.

In Figure 1, the reference numeral 1, a printing device of rotating design for printing bottles or similar containers shown. The

Printing device 1 has a plurality of printing stations 3, on each of which at least one print head 2 is provided. The printheads are in particular after the inkjet or ink-jet principle working digital printheads 2. Die

Printheads 2 each have a multiplicity of nozzles, which are provided successively on each print head 3, for example in a row in the vertical direction, and are individually electrically activatable. The application of the printing ink or printing ink to the nozzles is carried out by appropriate control of electrodes or piezo elements.

In more detail, the printing device 1 in the illustrated embodiment consists of a rotatable around a vertical machine axis MA, preferably continuously circulating rotatably driven rotor 6, at the periphery of a plurality of printing stations 3 are formed. Preferably, each printing station 3 is respectively associated with at least one print head 2, which is moved together with the respective printing station 3. The to be printed containers are the

3 pressure stations fed via a container inlet 7 and then moved together with this printing station 3 associated printhead 2, wherein the printing of the container 2 takes place during this movement. The printed containers 2 are taken from the respective printing station 3 at a container outlet 8.

The printing of the containers at the printing stations 3 is carried out, for example, line by line by relative movement of the container to the print head 2, in the illustrated embodiment in that each with its container axis in the vertical direction, i. oriented parallel to the axis of rotation of the rotor 6 container during printing is controlled by its container vertical axis rotated. The printing stations can be formed on the rotor 6 by individual circumferentially distributed arranged functional elements, for example, in each case at least one print head 2 and a container carrier, which is designed to receive a respective container, form a printing station 3. Furthermore, more

Functional elements, for example means for curing the printing ink or

Printing ink, etc. be provided. Alternatively, the peripherally provided on the rotor 6 printing stations 3 may each be formed by a pressure module, which is provided as such in entirety interchangeable on the rotor. Each printing module in this case has a housing or at least one support structure, in / on which all the functional elements necessary for the function of the printing modules are arranged, for example at least one print head 2 and at least one holding and

Centering unit for a container or means for holding and re-releasing such a holding and centering unit.

FIG. 2 shows, by way of example, a printing station 3 in the form of a printing module 20. As described above, the printing module 20 has a print head 2 with print head nozzles 2. 1. Furthermore, a receptacle 21 for a holding and centering unit (not shown) is provided on the printing module 20. Alternatively, the holding and

Centering also be part of the print module 20. In order to enable a highly accurate printing of the container, it is necessary to calibrate the at least one printhead 2 of each printing station 3, so that this printhead 2 occupies a desired position, hereinafter referred to as nominal position, during printing.

FIG. 3 shows a measuring system 10 for calibrating a printhead 2 of FIG

Printing station 3, which is designed for example as a printing module 20 as shown in FIG. However, the measuring system 10 can also be used to measure and calibrate a non-modular printing station 3, which is arranged on the rotor 6 of several

Single components is used (see Fig. 1).

The measuring system 10 comprises at least one measuring device 1 1, a

Computer unit 12 and an interface 13, preferably a

Transmission interface is. The measuring system 10 is based on an optical measuring method for position measurement of a position-variable component of the printing station 3. This position-variable component may be, for example, the print head 2 itself or a device for holding the print head 2. This device is referred to below as the printhead carrier 4. The measuring device 1 1 of the measuring system 10 is for detecting measurement information of the

position-variable component formed within the printing station 3. It can be formed for example by a camera, in particular a 3D camera or a laser scanner, for example a 3D laser scanner. The

Measuring device 1 1 is particularly for receiving multi-dimensional, in particular three-dimensional position information of the positionally variable

Component formed. For example, a 3D laser scanner provides three-dimensional point clouds and thus a complete multi-dimensional image of the

position-variable component or at least a portion of the component, which serves as a measuring point. Using the point cloud, for example, geometric variables such as lengths and angles can be determined. In the case of using a 3D camera as a measuring device 1 1 will contain image information that allow a geometric measurement of the recorded components of the printing station 3. Preferably, the measuring information during movement of the

Position variable component added. The component can be moved, for example, in different spatial directions, for example in mutually orthogonal stationary spatial directions (x-y-z-direction). Furthermore, the component may be provided pivotable at least about a pivot axis at the printing station, for example, to be able to print on inclined surfaces (container shoulder) on a container. Preferably, the position variable component is moved and / or pivoted over its entire adjustment. During this movement, measurement information is received by the measuring device 1 1. Alternatively, it is possible that only parts of the

Adjustment be traversed or individual points are approached in the travel range and at these individual points measurement information

be recorded.

The measurement information provided by the measuring device 11 is transmitted to a computer unit 12 of the measuring system 10. The computer unit 12 can be coupled to the measuring device 11, for example, by wire or wireless. In one embodiment, the computing unit 12 receives the

Measurement information and determines from this received measurement information a set of actual position data of the measured, positionally variable component. This set of actual position data includes, for example, a plurality of

Position values in three-dimensional space, in particular x, y and z coordinates, at which the positionally variable component was located at different times during the measurement.

Furthermore, setpoint position data are stored in the measuring system 10, which indicate target position values of the position-variable component after the calibration. In other words, the desired position data are those position data at which the positionally variable component should ideally, ie, be in the calibrated state. The desired position data contain, for example, a multiplicity of position values in three-dimensional space, in particular x, y and z coordinates, at which the positionally variable component moves along the should preferably be multi-dimensional displacement. The measuring system 10 may for example comprise a memory unit in which the desired position data are stored. By comparing the actual position data with the desired position data, calibration information can be obtained which can be used to calibrate the printhead 2. For example, the deviations between the actual position data and the desired position data are determined and based on the deviations calibration information, for example in the form of

Versteilgrößen determined based on which the print head 2 must be adjusted to achieve its calibration. The calibration information or the magnification variables are preferably determined by the arithmetic unit 12.

Preferably, the computer unit 12 for performing a

Optimization routine be designed to be based on a variety of

Position values in the actual position data and position values in the desired position data are the most suitable for calibrating the print head 2

To determine the size of the part. The Versteilgrößen can specify, for example, by what amount and in which direction the position variable component has to be moved or pivoted.

The obtained calibration information or the adjustment variables are provided by the measuring system 10 at the interface 13.

The calibration of the printhead 2 based on the calibration information can be done in different ways. In a first embodiment, the calibration information can be transmitted directly to the respective printing station 3 and thus a calibration of the print head 2 can be performed.

For example, actuators, in particular motor drives, the one

Adjusting the position of the printhead 2 in the printing station 3, driven based on the calibration information, so that the printhead 2 is moved to a calibrated position. It can also be a caching in one

Storage unit of the measuring system 10 are made. In a second embodiment, as shown in FIG

Calibration information stored in one of the printing station 3 associated memory unit 5. This is particularly advantageous when designed as interchangeable printing modules 20 printing stations 3. By means of the calibration information stored in the printing station 3 or in the printing module 20, it is possible for each printing station 3 to calibrate without access to a central memory unit.

For example, calibration information may be after maintenance or

Repair of components of a printing module 20 determined by the measuring system 10 far away from the installation of the device 1 and stored in the printing module 20. The actual calibration then takes place after connection of the printing module 20 with connection points provided on the rotor 6. In other words, after attaching the printing module 20 to the rotor 6, the print head 2 of the respective printing module 20 is calibrated based on the calibration information stored in the memory unit 5.

In a third embodiment, as shown in Figure 4, the

Calibration information in one of the printing device 1 associated

Memory unit 14 stored. The associated with the printing device 1

Memory unit 14 may in particular be a central memory unit which is coupled to all the printing stations 3 of the printing device 1, so that in this memory unit 14 the respective printing stations 3 associated

Calibration information can be stored. If necessary, for example in the

Commissioning of the printing device 1 or even at a

Interim calibration, the calibration information can be read and transmitted to the respective printing stations 3, so that they can make the calibration of the printheads 2 based on the calibration information. Alternatively, the memory unit may also be provided in the measuring system 10 or assigned to this measuring system 10. The measuring system can preferably be adapted to the given design of the printing station 3 or the printing device 1. In the event that the printing stations 3 are designed as exchangeable printing modules 20, the measuring system 10 can be designed to receive a respective printing module 20. For example, on the measuring system 10 may be provided a holder, a receptacle or a stop, by means of which the printing module 20 can be aligned in a desired relative position to the measuring device. Other measures are conceivable. In the event that the printing stations 3 are not provided interchangeably on the rotor 6 or in the event that several printing stations 3 are to be measured or calibrated when arranged on the rotor 6, the measuring system 10, as shown in Figure 4, before the the printing stations 3 having rotor 6 are placed.

For example, the measuring device 1 1 on a tripod or similar. be placed at the level of the printheads 2 in front of the rotor 6, in such a way that a

Recording of measurement information of the printhead 2 or a printhead support 4 is possible.

In the calculation of the actual position data from the measurement information obtained from the measuring device 1 1 can not as a reference point with the

position variable component mitbewegter area of the printing station 3 can be used. This may in particular be the receptacle 21 for holding a holding and centering unit or, in the case in which the holding and centering unit is part of the printing station 3, an area of the holding and centering unit itself.

In a preferred embodiment, the measurement or calibration of the printing station 3 is performed in several steps. As a result, a higher accuracy in the printing station calibration can be achieved. The measurement can be carried out in particular in two separate steps. In a first step, for example, the position of the print head carrier 4, by means of the

Printhead 2 positionally variable in the printing station 3 is held, measured, and that when moving the same over a portion of its adjustment or over the entire adjustment. This measurement of the print head carrier 4 can preferably take place with the print head 2 removed. During the first step, a first set of measurement information is thus obtained, which contains information about the actual position of the print head carrier 4 in different adjustment positions. This first set of measurement information can be found in the central storage unit 14 or the printing station 3 associated storage unit 5 are stored.

Subsequently, or in the temporal offset to the first surveying step, a second measuring step is carried out, in which the position of the print head 2 is measured, namely when it moves over part of it

Adjustment range or over the entire adjustment range. In other words, between the first surveying step and the second surveying step, the printhead 2 is installed on the printhead carrier 4. When measuring the print head 2, as described above, a specific area of the print head 2 can be selected as a reference point, for example a reference area of the print head 2

Printhead 2 or printhead nozzle 2.1. The calculation of

Calibration information is then based on the

Measurement information that in the first survey step and in the second

Surveying step were obtained.

The invention has been described above by means of exemplary embodiments. It is understood that a variety of changes or modifications are possible without thereby departing from the inventive concept underlying the invention.

LIST OF REFERENCE NUMBERS

1 printing device

2 printhead

2.1 printhead nozzle

3 printing station

Print head carrier

5 storage unit

6 rotor

7 container inlet

8 container outlet

10 measuring system

1 1 measuring device

12 computer unit

13 interface

14 storage unit

20 printing module

21 recording

MA machine axis

Claims

claims

1 . Measuring system for measuring a printhead (2)

Printing station (3), wherein the print head (2) is held in position adjustable at the printing station (3), wherein the measuring system (10) comprises:

- At least one measuring device (1 1), for the detection of

Measuring information of a position-variable component of the printing station (3) is formed during its movement;

- A computer unit (12) adapted to receive the measurement information provided by the measuring device (1 1), wherein the

Computer unit (12) for determining actual position data of the position-variable component from the received

Measurement information, for comparing this actual position data with predetermined desired position data and for determining

Calibration information is formed based on the actual position data and the target position data;

- An interface (13) for transmitting the calibration information.

2. Measuring system according to claim 1, characterized in that the

Measuring device (1 1) is designed to determine three-dimensional measurement information.

3. Measuring system according to claim 1 or 2, characterized in that the

Measuring device (1 1) is a camera, preferably a 3D camera or a laser scanner, preferably a 3D laser scanner.

4. Measuring system according to one of the preceding claims, characterized

in that positionally variable component is the print head carrier (4) or a region of the print head (2).

5. Measuring system according to one of the preceding claims, characterized

in that the positionally variable component is at least one printhead nozzle (2.1).

6. Measuring system according to one of the preceding claims, characterized in that the positionally variable component is at least one reference surface of the print head (2).

Measuring system according to one of the preceding claims, characterized

in that the printing station (3) is an exchangeable printing module (20) and that the measuring system (10) is designed for the positionally accurate alignment and / or mounting and measuring of this printing module (20).

Measuring system according to one of the preceding claims, characterized

in that the interface (13) is designed for coupling to a memory unit (5) provided in the printing station (3) or in the printing module (20) and for transmitting the calibration information to this memory unit (5).

Measuring system according to one of the preceding claims, characterized

in that the interface (13) is designed for coupling to a central memory unit (14) and transmission of the calibration information to this memory unit (14), wherein the memory unit (14)

- Part of a printing device (1) for a plurality of printing stations (3) and / or printing modules (30) is or

- is part of a central server and / or a data cloud.

Measuring system according to one of the preceding claims, characterized

characterized in that the computer unit (12) for determining

Calibration information is formed, the movement information for the position-variable component to calibrate the same contained on a target position. 1 1 measuring system according to one of the preceding claims, characterized

in that means for exact positioning and / or alignment of the measuring device (11) relative to the printing station (3) are provided. Method for calibrating a printhead (2)

Printing stations (3) comprising the following steps:

- Providing a measuring device (1 1), for the detection of

Measurement information of a positionally variable component of

Printing station (3) is formed;

- Moving the position-variable component relative to

Measuring device (1 1);

- Acquire measurement information during the movement of the

position-variable component by the measuring device (1 1);

- transferring the measurement information to a computer unit;

- determining actual position data from the measurement information;

- Determining calibration information from the actual position data and

predetermined desired position data;

Calibrating the printhead (2) based on the calibration information.

A method according to claim 12, characterized in that the

Position variable component during detection of the measurement information at least in two, preferably three independent spatial directions moved and / or is pivoted about at least one pivot axis.

A method according to claim 12 or 13, characterized in that

Measurement information of a print head carrier (4) and / or a region of the print head (2), in particular at least one print head nozzle (2.1) or a reference surface of the print head (2) are obtained.

Method according to one of claims 12 to 14, characterized in that the calibration method is carried out in two stages, wherein in a first measurement step, first a set of measurement information regarding the moving printhead support (4) and in a second measurement step, a set of measurement information with respect to a region of the moving Printhead (2), in particular at least one printhead nozzle (2.1) or a reference surface of the print head (2) is determined and that based on the in the first and second measurement step determined measurement information, the calibration information can be determined.

6. The method according to any one of claims 12 to 15, characterized in that the printing station (3) is calibrated directly by the determined calibration information.

7. The method according to any one of claims 12 to 15, characterized in that the calibration information in a central, for a plurality of printing stations (3) provided storage unit (14) are stored and the respective

Printing station (3) is calibrated after transmission of the calibration information to this printing station (3) based on this calibration information.

8. The method according to any one of claims 12 to 15, characterized in that the calibration information in a in the respective printing station (3)

provided storage unit (5) are stored and the printing station (3) using this in the memory unit (5) stored

Calibration information is calibrated.