EP3411240A1

EP3411240A1 - Printing method and printing device

Info

Publication number: EP3411240A1
Application number: EP17702870.1A
Authority: EP
Inventors: Andreas SCHMIDT E.K.
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-02-05
Filing date: 2017-02-03
Publication date: 2018-12-12
Anticipated expiration: 2037-02-03
Also published as: HRP20210346T1; US20190039386A1; US11084301B2; PL3411240T3; ES2856885T3; DK3411240T3; PT3411240T; CN109070603B; CN109070603A; WO2017134193A1; CA3012904C; EP3411240B1; WO2017134193A4; CA3012904A1; DE102016201821A1

Abstract

The invention relates to a method and a device for printing a large surface which is situated, in particular, on a substrate which cannot be fed to a printing device. The method is distinguished by the fact that the perpendicular spacing Azo of a reference point of the device (100) at a plurality of points which are distributed over the printing web from the surface (300) to be printed is determined in each case at the points which are distributed over the printing web, and the perpendicular spacing A_z of the print head (200) from the surface (300) to be printed is set in accordance with a previously recorded measured value. Here, the plurality of points can be distributed uniformly over the length of the printing web. The device (100) for carrying out the method has a measuring device (190) for contactless measurement of the spacing between a reference point of the device (100) and the surface (300) to be printed. Furthermore, the device (100) has a control unit for evaluating the measured values and producing control pulses for setting the spacing A _z of the print head (200) from the surface (300) to be printed.

Description

Printing method and printing device

Description:

The invention relates to a method and a device for printing a large area, in particular a large, located on a non-feedable to a printing substrate surface. Examples of such surfaces are building walls, walls of trucks or railway carriages, surfaces on containers or entire ship's side walls.

Large format printers have been known for many years. With such printers, it is possible to print paper, but also other substrates up to 5m wide or even beyond, and a theoretically endless length. The printing takes place in one plane, i. two-dimensional, over a printing table. In these printers, the printing table is formed more or less linear, i. its extension in the width direction transverse to the feed direction of the substrate is significantly greater than in the substrate feed direction. Typically, the substrate is rolled up on a roll and fed to the printer, which feed covers the first axis of the two-dimensional printing operation. Transversely to this axis, a printhead moves with a

Paint application system over the substrate. Ink jet printers are widely used, the ink to be applied being an ink which is sprayed onto the substrate in droplets via nozzles which are controlled by a controller. Several nozzles for different colors can be arranged side by side in the print head, whereby a multi-color print is possible. The printing plane usually corresponds to the horizontal. Because of the feed, the substrate must be flexible at least in the longitudinal direction.

In addition, flatbed printers are also known. In such printers, the substrate is clamped in a bed, the printing table. The print head is attached to a cross table, whereby the print head itself in the two directions of a Level is movable. With such flatbed printers, it is possible to print even rigid substrates. The dimensions of such cross tables are finite and can not be increased arbitrarily, since the axes of the cross table can be stored only at their end points and still have to have a minimum stability. Even with flatbed printers, the substrate is supplied to the printer.

In both systems, by feeding the substrate to a printing table, the spacing of the printhead in the spatial direction, i. perpendicular to the plane spanned by the x- and y-direction and here and in the following called z-direction, constant and precisely defined. This distance is important to get a clean print image. The ink nozzles are focused on this distance.

With both systems, it is not possible to change the area of a non-moving

Substrate, for example, the wall of a room or building to print.

Recently, wall printers have become known with which it should be possible to print on walls. These printers use printheads more commercially

Inkjet printers, which are in one direction, here and hereinafter named vertical direction or y-direction, movably mounted on an axis. This axle is mounted on a chassis with the chassis in one direction

Substantially perpendicular to the vertical direction, here and below

called horizontal direction or x-direction, is movable. The printing principle corresponds to that of the large format printer described first: The vertical direction of the print head is realized by its up and down movement in the y direction, while the horizontal direction is realized by the movement of the chassis in the x direction. The printhead now prints a vertical web with a y-directional extent defined by the printhead, i. with a web width in the horizontal direction. For printing one in a horizontal direction

adjacent track, the chassis is moved in the x-direction past a wall, while the printhead dwells in the upper or lower end position.

In practice, however, there are some problems: Is the floor is not even, which is the case, for example, with tiled floors because of the joints between the tiles Usually this is the case, these bumps are transferred to the printed image. To solve this problem drive known wall printer on a

Rail system that bridges such bumps. The disadvantage of this is that the rails must be designed and aligned, which means effort, and on the other hand for long walls to be printed long rails are required, which increases the transport cost of the wall printer to a job site, increases the cost of the wall printer and turn the Increased printing effort.

Another problem of known wall printers is the limited height of the printable area: the y-axis consists of a profile of a finite length of typically 2 m, the printhead movement being along this axis via a toothed belt. Thus, the length of the y-axis is initially not extendable or only with great effort. In addition, the attachment and design of the stability of the y-axis is designed for this length, so that a

Extension of the axis due to mechanical instability and associated fluctuations in the x and z directions of the y-axis would lead to a very unsatisfactory printed image. Furthermore, walls of structures are rarely aligned exactly perpendicular to the ground, but usually inclined relative to the ground. Although the inclination is in most cases only small angular dimensions of a few degrees. Above a room height of usually about 2.50 m for

Residential buildings and significantly more for commercial buildings but also 1 ° tilt already makes a difference of about 4 cm, causing the printed image in terms of

Contour sharpness between the bottom end and the top end very different. In the prior art, the measurement for a subsequent tracking of the distance of the print head to the wall is the

Use of ultrasonic sensors known. These sensors are mounted on the printhead and therefore are only able to detect the distance in real time, ie the moment the printhead is in place. A readjustment based on such a measurement can only be very imperfect because of the dead time between measurement and readjustment. In addition, a wall can also have unevenness that can destroy the print head when it collides with them. The y-axis of known wall printers are mounted in the x-direction more or less centrally on the chassis, at least they are not mounted on an x-axis end of the chassis. Thereby it is not possible to print in a corner. In other words, more or less wide, non-printable strips remain in the corners of the room. The rails for the chassis are only straight laid, ie the printing of curvy surfaces is not possible. Also, today it is only possible to print on surfaces that print perpendicular to the ground on which the chassis drives. The printing of differently oriented surfaces, such as ceiling or floor surfaces is not possible. Especially right, it is not possible to print three-dimensionally shaped surfaces, such as vaulted ceilings.

The object of the invention is therefore to provide a method for printing a large, in particular located on a non-feedable to a printing substrate large area specify that described above

Circumvents limitations and disadvantages. It is another object of the invention to provide a device for carrying out the method.

According to the invention, this object is achieved by a method having the features of independent claim 1. Advantageous developments of the method will become apparent from the dependent claims 2-6. The object is further achieved by a device according to claim 7. Advantageous embodiments of the device will become apparent from the dependent claims 8-13.

The inventive method is suitable for printing a large, located on a non-feedable to a printing substrate substrate. , Surfaces, such as walls of buildings, trucks or railway carriages, surfaces on containers, etc., wherein the area to be printed in one direction in printing webs according to the printing width of a printhead is divisible and wherein the printhead on a first axis along a

Movement web is movably mounted, the first axis is fixed to a horizontally movable in the x-direction chassis and the surface is printed by the sequential printing of the printing lines. The method is characterized in that the vertical distance A _{z0 of} a reference point of the device determines at several points distributed over the printing web to the surface to be printed and the vertical distance A _{z of} the print head from the surface to be printed at the points distributed over the printing web each one according to one previously recorded measured value. The multiple points can be distributed uniformly over the length of the printing web. When deciding on the number of dots, the flatness of the area to be printed and / or the expected number and extent of imperfections on the area to be printed can be taken into account. With a very even surface without significant impurities, a few points are sufficient, with uneven surfaces with many

Defects, especially if at least some of these impurities have large dimensions, many measurement points should be recorded. In extreme cases, the number of measurement points can be chosen so large that a quasi-continuous measurement is present. The recorded measured values of each printing web can be stored in measurement series for each point measured along the printing web, wherein a trend is determined from the measured values of at least one measurement series, wherein a steering movement of the horizontally movable

Chassis is triggered when the trend exceeds a previously defined threshold. For example, if the area to be printed is a vertical wall, for example a wall of a living space, substantially perpendicular to the floor surface on which the horizontally movable chassis moves, a steering movement of the chassis will be triggered as the distance of the wall from the undercarriage in the Changed during the movement of the chassis,

For example, because the wall direction kinks or the wall describes a curve. The measured values of each measurement at a specific height are combined in the control device into measurement series and a trend is calculated. If the trend of at least one series of measurements exceeds a predetermined one

Threshold changes, is outputted by the control device, a steering pulse to the chassis, so that the distance of the chassis moves from the wall back into the previously defined corridor. In this way, it is possible to print on walls that follow a curve or whose course changes from a direction initially taken

The device for carrying out the method has a measuring device for measuring the distance between a reference point of the contactless measurement

Device and the surface to be printed on. The device furthermore has a control unit for evaluating the measured values and generating Control pulses for the adjustment of the distance A _{z of} the printhead from the surface to be printed on.

With the adjustment of the distance A _{z of} the printhead from the wall to be printed, the problems of the prior art with respect to a contour-sharp printed image despite not exactly level and equidistant alignment to

printed surface opposite the printhead solved. In order to be able to set the distance A _{z of} the print head at each location on the printing web so that it is always the same despite unevenness or, for example, non-vertical walls, the distance A _z must be determined. This is done in a preferred embodiment without contact, preferably optically, for example with a

Laser rangefinder. Since the distance A _{z of} the print head from the

printing surface is set so that it always has the same distance A _z , it can not collide, for example, with a roughness on this surface. The measurement is made via a reference point of the device. This reference point may, for example, be located on the first axis at which the print head is moved along a print path. As a result, the reference point is moved together with the print head along a print path, so that the distance A _{z0 of} the reference point to the corresponding print head positions is known. About the known geometric relationships of the device, the required print head position with respect to the distance A _z of the zu

be determined on the printing surface. At the reference point can a

appropriate distance measuring device attached. The reference point can be arranged in the horizontal x-direction next to the print head, so that the distance A _{z0 of} the reference point from the surface to be printed precedes the print head when printing in one direction. This is the preferred printing direction. By anticipating the distance is already measured while the printhead still leaves the previous print path. This gives the control unit a time lead for the calculation of the print head distance A _z of the surface to be printed.

In a preferred embodiment of the inventive method, the first printing web is traversed without activating the print head at the beginning of a printing process, wherein the vertical distance A _{z0 of} a reference point of Printhead at several distributed over the vertical print path points to the surface to be printed vorausilend to the worn off in the measurement

Printing web is determined. The printhead travels the first swath of the print image without printing. Advantageously, the printhead is for this ride in a position as far away from the surface to be printed. In this driving only the distance measuring device is active. The recorded

Distances are sent to the control unit and there calculated for the position of the print head for a constant distance A _{z of} the print head from the wall for each location on the print web. Subsequently, the same printing web is traversed again, this time the print head is active and printed the area under the web.

In an advantageous embodiment, starting position of the print head is optically displayed at the beginning of a printing web. In a particularly advantageous

Embodiment, the start position of the printhead is optically displayed at the beginning of each print path. For this purpose, the printhead has an optical

Display means. This optical display device may be, for example, a laser lamp. In particular, the optical display device can

Be a laser pointer. A laser pointer projects in a conventional manner a point of light on the substrate to be printed and thus indicates at which point the print head is located. If this point is not identical to the point at which the print path begins, the print head can be readjusted accordingly.

It has proven to be advantageous if the printing is carried out by the application of ink to the substrate, wherein the ink to a temperature of about 43 ° C.

is tempered. The device has a corresponding

Tempering. The printing is done by a known

Inkjet printhead, which has several nozzles for example for the

Can have multi-color printing. The use of different inks is basically possible. Especially when the area to be printed in the

It is advantageous to use a waterproof and UV-stable ink, which withstands exposure to rain and irradiation with sunlight for at least a certain time. Such inks can be optimally processed at a temperature of about 43 ° C, the possible processing temperature interval is about 1 K. It has proven to be advantageous if the ink is stored in bags and conveyed from bags, the bags are made of an aluminum alloy. In a

Advantageously, the ink bags are stored in the device on a single surface heating in the form of boards, wherein the

Heating power of the surface heating systems are regulated, with the respective

Actual temperature of the surface heating is detected by a sensor and the information is fed to a control device. The aluminum alloy of the ink bags have a good thermal conductivity, so that the ink temperature can be controlled very well by the surface heating temperature.

In a further advantageous embodiment, the print head via a

Device shaded by UV radiation when it is not active. The device has a movable shading device. Inks which have good water resistance and UV stability, as well as good color brilliance and abrasion resistance properties, are for example UV-curing. After the ink has been applied to the substrate, it cures under UV light, i. polymerize the monomers in the paint and the

Color pigments are fixed in the solid polymer layer. Thus, these inks should be shaded by UV light, as long as they are not yet applied to the substrate. For this purpose, the device has a device, for example in the form of a displaceably mounted plate, which can be pushed over the print head when it is inactive. Does the print head have multiple nozzles?

For example, for different colors, so the plate can several

Have openings that cover the different nozzles or release after moving the plate for printing again. In a

Embodiment, the plate is a stainless steel sheet having a possible travel of, for example, 4 mm.

It is conceivable that the print head is pivoted in dependence on the orientation of the surface to be printed, so that the print head is always in the

Aligned substantially perpendicular to the surface to be printed. Walls of buildings, for example, have projections or recesses, wherein the wall course at an angle in the direction of projection or depression emotional. By pivoting the print head, it is possible to print even those running at an angle wall parts. It is also possible to print on ceilings or floors. In particular, it is also possible, for example

To print vaulted ceilings where a wall is continuously placed in a ceiling, i. a substantially perpendicular to the original orientation of the wall surface pivoted orientation extends.

A device according to the invention for printing large, in particular located on a non-feedable to a printing device substrate surface, such as walls of buildings, trucks or railway carriages, surfaces on containers, etc., in one direction in pressure paths according to the printing width of a printhead einteilbaren surface, said the printhead is movably mounted on a first axis along a printing web, the first axis being fixed to a chassis movable in the horizontal x-direction, and the surface being printable by the sequential printing of the printing webs, characterized in that the distance A _{z of} the print head of the surface to be printed is adjustable and the device _comprises a measuring device for contactless measurement of the distance A _z0 between a reference point of the device and the surface to be printed and the device further _comprises a control unit for evaluation the measured values and generating

Control pulses for adjusting the distance A _{z of} the print head from the surface to be printed.

The chassis is movable in the horizontal x-direction, wherein the chassis is designed steerable and the device further comprises a control unit for calculating the steering angle of the chassis. For this purpose, the recorded measured values of each printing web for each point measured along the printing web are stored in measurement series, and a trend is determined from the measured values of at least one measurement series, wherein a steering movement of the chassis movable in the horizontal direction is changed if the trend exceeds a previously defined threshold.

It is conceivable that the print head to at least 180 ° pivotable about the

Horizontal is movably mounted on a third axis along a pressure path. Due to the pivoting of the print head, it is possible to print in the room inclined surfaces. It is also possible to print walls or floors. Finally, it is even possible to print surfaces whose spatial orientation changes continuously, as is the case with vaults, for example.

In a further advantageous embodiment, the device has a

extendible first axis for the movement of the print head along a

Printing web, wherein the first axis has a rack. By the

Using a rack, the first axis is easily extendable, for example, by another axle module, also equipped with a rack, is applied to the existing first axis. A unit supporting the print head, in one embodiment, includes a servo motor which drives a gear meshing with the first axis rack, whereby the unit supporting the print head is very precisely and smoothly movable along the first axis, even if the first axis extends is.

In a further advantageous embodiment, the device has a second axis for adjusting the distance A _{z of} the print head from the

printing surface, wherein the second axis has a spindle.

Advantageously, the second axis is part of the unit which carries the print head. It has proven to be advantageous if the spindle of a servomotor

is driven. As a result, the distance A _{z of} the print head from the surface to be printed can be set very precisely and quickly.

The chassis has wheels that allow it to stand on a ground and move in a horizontal x-direction. It has proved to be advantageous if the chassis has at least three, in particular four wheels, wherein the wheels are arranged at its respective corners. Each wheel can have adjustable height compensation. The chassis itself may have a measuring device with which the horizontal orientation of the chassis is verifiable. In addition, the chassis may have at its corners in the vicinity of the respective wheel via a distance measuring device. This is preferably non-contact, preferably designed as an optical measuring device. Furthermore, the chassis may have a control device on the function of the measurement results of each distance measuring device, the height compensation of each wheel can be activated so that the chassis leveled itself at any time, especially if the floor is tiled, for example, and has deeper joints between the tiles. In addition, an activated affects

Height compensation of each wheel advantageous to the juddering freedom of the horizontal movement of the chassis.

The device can have a device for displacing the print head in the direction or opposite to the direction of the movement direction of the chassis, in particular via a third axis in this direction. This third axis can serve to move the print head to the end points or over the end points of the chassis in the direction of movement of the chassis. Is the area to be printed, for example, a wall of a

Living space, with the help of the third axis is possible to print in the corners and because of the necessary expansion of the chassis in

Direction of movement unprintable areas of the wall in

Minimize or even eliminate movement direction of the chassis.

The chassis is able to move forwards and backwards in the direction of movement. It has an engine for this purpose. This motor can be a stepper motor or a servomotor. You can move one or more wheels

be driven. The one or more wheels may be driven directly or via a gear, wherein the wheel or wheels may be rigidly or via a transmission member, such as a chain or a belt, such as a toothed belt, connected to the engine.

For the realization of the function of the pivoting of the printhead, the alternatives are to swing only the printhead or a

Print Head Carrying Unit consisting of the third axis with orientation in

Movement direction of the chassis together with the printhead to pivot. Further advantages, features and expedient developments of the invention will become apparent from the dependent claims and the following description of preferred embodiments with reference to the drawings.

From the pictures shows:

Fig. 1 An inventive device in a three-dimensional schematic diagram

Fig. 2 The device according to the invention in a plan view when printing a wall surface

Fig. 3 The device according to the invention in a plan view when printing a wall surface near a wall corner

4 shows a printhead 200 according to the invention in a schematic diagram

1 shows a device 100 according to the invention in a three-dimensional schematic diagram. The device 100 has a chassis 1 10 which is movable on four wheels 1 1 1 in the horizontal x-direction on the floor 400. At the corners of the chassis 110, a distance measuring device (not shown) is provided near each wheel. This optically measures the distance to the ground 400 and forwards the measurement signal to a controller (not shown). Each wheel 1 1 1 has an adjustable height compensation (not shown). In

Dependence of the measurement results of each distance measuring device is the

Height compensation of each wheel 1 1 1 activatable, so that the chassis 1 10 leveled itself at any time, especially if the floor 400, for example, tiled and has deeper joints between the tiles. The device 100 further has a first axis 120 in the y-direction. This first axis 120 has a rack which is mounted in the y-direction on the axis. The first axis 120 may be implemented in a standard industry profile, with the

Rack sunk and thus comes to lie protected in the profile. The first axis 120 is extendible by attaching one or more axis modules, which may also be implemented in the standard industry profile, to the first axis. The attachable axis modules also have a rack. For example, the first axis 120 in the non-elongated embodiment is about 2.50 meters long, allowing it to be used in residential buildings with standard ceiling heights. If higher areas 300 are to be printed, for example, in a commercial property or on an external facade, the first axis 120 can be extended with corresponding axis modules so that printing lines of more than 2.50 m in length can also be printed.

On the first axis 120, a second axis 130 is attached via a slide 121 with a main extent in the z-direction. The carriage 121 has a drive in the form of a servomotor and a meshing with the rack of the first axis 120 gear. By the up and down movement, which can exert the second axis 130 and attached to the second axis 130 printhead 200, a printing web in y-direction can be traversed by the print head 200 and printed. After completion of this printing web, the device 100 can be moved by means of the chassis 1 10 by a printing web width in the x direction, so that the next printing web can be printed. Attached to the carriage 121 is a measuring device 190 in the form of a laser rangefinder. This measuring device sends a measuring beam 192 in the direction of

printing surface 300 from where it impinges on a measuring point 191. The

Removal of the measuring device 190 from the surface to be printed 300 in this point 191 is recorded and as a reference _distance A _z0 to a

Control device of the device 100 is sent, where it is stored. The second axis 130 has a spindle. In the carriage 121 is another servo motor for driving the spindle. About the evaluation of the

Reference point _distance A _z0 in the control unit can be close to the current distance A _{z of} the print head 200 of the surface to be printed 300. The servo motor and spindle allow this distance to be set quickly and precisely to a preset value set in the control unit. As a result, the distance A _{z of} the print head from the to

very precise and fast adjustment of the printing area.

On the second axis 130, an axle head 131 is attached to the end facing the surface to be printed 300. This axle head 131

In turn, it houses a servomotor, which has a third axis 140 with alignment in x direction, ie the direction of movement of the chassis 1 10, drives. At this third axis 140, the print head 200 is movably mounted in the x direction. Thus, the print head 200 can be moved independently of the movement of the chassis 1 10 in the x direction. This is advantageous when it is to be printed in a wall corner, with a non-printable area to be minimized.

The third axis 140 is pivotally mounted on the axle head 131, wherein the pivoting range is at least 180 °. Thereby, the print head 200 can both be pivoted upwards, whereby, for example, a ceiling

is printable, as well as swung down, whereby the floor on which the chassis 1 10 is placed movable, can be printed.

For the printing of a room ceiling and the second axis 130 is rotatably mounted together with the axis head 131, third axis 140 and printhead 200 in the carriage 121, wherein the rotational movement is at least 90 °, so that at a corresponding rotation up the ceiling printable is.

FIG. 2 shows the device 100 when printing on a wall surface 300 in a plan view from above. At least two wheels 1 1 1 are steerable, so the

Chassis can also follow a curvy wall. The device has a control unit for calculating the steering angle of the chassis 1 10. The recorded measured values A _z0 of each printing web for each point measured along the printing web are stored in measurement series and a trend is determined from the measured values of at least one measurement series, wherein a

Steering movement of the horizontally movable chassis 1 10 is changed when the trend exceeds a previously defined threshold.

FIG. 3 shows the device 100 when printing on a wall surface 300 in a plan view from above, wherein the device 100 is located in a corner formed by two walls. The printhead 200 is moved to the corner end of the third axis 140 to print into the corners and to minimize or even eliminate the areas of the wall 300 in the direction of travel of the chassis 100 that are not to be printed due to the necessary expansion of the chassis 100 , 4 shows a printhead 200 according to the invention in a schematic diagram. The printhead 200 has four nozzles 220 located behind a shadow plate 210. The Abschattplatte 210 has four slots 21 1, wherein the Abschattplatte 210 is slidably mounted in a guide 212 in the y-direction, so that the nozzle 220 shaded by the Abschattplatte against UV radiation, when the nozzles are inactive. Furthermore, the print head 200 has a laser pointer 230, by means of which the position of the print head 200 can be displayed at the beginning of a printing web on the substrate to be printed. The print head 200 has printed circuit boards 240, which are arranged in a row above one another in the interior of the print head 200. The boards 240 have a tempering device. Certain inks can be optimally processed at a temperature of approx. 43 ° C. The ink is stored in bags and conveyed, the bags are made of an aluminum alloy. The ink bags are stored in the printhead 200 on individual area heaters disposed on the boards 240.

The embodiments shown herein are only examples of the present invention and therefore should not be considered as limiting. Alternative embodiments contemplated by one skilled in the art are

equally within the scope of the present invention.

LIST OF REFERENCE NUMBERS

100 Apparatus for printing large, non-movable, surfaces

1 10 chassis

1 1 1 wheel

120 first axis, y-axis

121 sleds

130 second axis, z-axis

131 axis head

140 third axis, x-axis

190 measuring device

191 measuring point

192 measuring beam

200 printhead

210 shadow plate

21 1 slot

212 leadership

220 nozzle

230 laser pointers

240 board

300 area to be printed, wall

400 floor

Claims

claims:

1. A method for printing a large and in particular on a non-feedable to a printing substrate, in one direction in printing paths corresponding to the printing width of a print head (200) a divisible surface (300), wherein the print head (200) on a first axis ( 120) being movably mounted along a printing web, the first axis (120) being affixed to a chassis 110 movable in the horizontal x-direction, and the surface (300) being printed by the sequential printing of the printing webs,

characterized,

the vertical distance A _{z0 of} a reference point of the device (100) is determined at a plurality of points distributed over the printing web to the surface (300) to be printed, and the vertical distance A _{z of} the print head (200) from the surface to be printed (300) to the points distributed over the print path are each set according to a previously recorded measured value, wherein the recorded measured values A _z0 of each

Print path for each point measured along the print path are stored in measurement series and from the measurements of at least one measurement series a trend is determined, wherein a steering movement of the horizontally movable chassis (110) is changed when the trend exceeds a previously defined threshold.

2. Method according to claim 1,

characterized,

at the beginning of a printing operation, the first printing web is traversed without activating the printhead (200), wherein the vertical distance A _{z0 of} a reference point of the printhead (200) at several points distributed over the vertical printing web to the surface to be printed (300)

in anticipation of the worn-out during the measurement printing web is determined.

3. The method according to claim 1 or 2,

characterized,

that the start position of the print head (200) at the beginning of a printing web is visually displayed.

4. Method according to one of the preceding claims,

characterized,

that the print head (200) is pivoted in dependence on the orientation of the surface to be printed (300), so that the print head (200) always in

Aligned substantially perpendicular to the surface to be printed (300).

5. Method according to one of the preceding claims,

characterized,

the printing is effected by the application of ink to the substrate, the ink being heated to a temperature of about 43 ° C.

6. Method according to one of the preceding claims,

characterized,

that the print head (200) is shadowed by a device of UV radiation when it is not active ..

7. Device (100) for printing a large and in particular on a non-feedable to a printing device substrate, einteilbaren in one direction in print paths corresponding to the printing width of a print head surface (300), wherein the print head (200) on a first axis (120 ) is movably mounted along a printing web, wherein the first axis (120) is fixed to a carriage (110) movable in the horizontal x-direction, and wherein the surface (300) is printable by the sequential printing of the printing webs,

characterized,

in that the distance A _{z of} the print head (200) from the surface (300) to be printed is adjustable, and the device (100) _comprises a measuring device (190) for measuring the distance A _z0 between a reference point of the device (100) and the print object Surface (300) and the device (100) further comprises a control unit for evaluating the

Measurement values and generation of control pulses for setting the distance A _{z of} the print head (200) from the area to be printed (300) wherein the chassis (110) is movable in the horizontal x-direction, wherein the chassis (110) is designed steerable and the device (100) further comprises a control unit for calculating the steering angle of the chassis (110).

8. Device (100) according to one of claims 8 to 9,

characterized,

in that the measuring device for measuring the distance A _z0 between a reference point of the device (100) and the surface to be printed (300) _comprises a laser rangefinder.

9. Device (100) according to one of claims 8 to 10,

characterized,

in that the print head (200) has an optical sensor for detecting the start point of the print head (200) at the beginning of each print web.

10. Device (100) according to one of claims 8 to 11,

characterized,

in that the device (100) has an extendable first axis (120) for the

Movement of the print head (200) along a pressure path, wherein the first axis (120) axis has a rack.

11. Device (100) according to one of claims 8 to 12,

characterized,

in that the device (100) has a second axis (130) for adjusting the distance A _{z of} the print head (200) from the surface (300) to be printed, the second axis (130) having a spindle.

12. Device (100) according to one of claims 8 to 13,

characterized,

the device (100) has a tempering device for tempering ink to a temperature of about 43 ° C.

13. Device (100) according to any one of claims 8 to 14, d a d e c e c e n e c e n e,

in that the device (100) has a movable shading device which shadows the print head (200) when UV radiation is not used.