METHOD AND MACHINE FOR PRINTING ON A WORKPIECE

Abstract

The invention relates to a method for printing on a panel-like workpiece (W), which has wide faces and lateral faces, in the machine, which comprises at least one digital printing device (10), in particular an inkjet printing device, comprising the following steps: bringing ab out a relative movement between the workpiece and the at least one digital printing device and printing on at least one of the wide faces and at least one of the lateral faces of the workpiece (W) in the machine.

Claims

1. A method for printing on a panel-like workpiece, which has wide faces and lateral faces, using a machine that comprises at least one digital printing device, the method comprising the following steps: bringing about a relative movement between the workpiece and the at least one digital printing device; and printing on at least one of the wide faces and at least one of the lateral faces of the workpiece in the machine.

2. The method according to claim 1, wherein and entire surface of each face of the workpiece is printed on.

3. The method according to claim 1, wherein the machine comprises a conveyor system in order to bring about a relative movement between the workpiece and the at least one digital printing device.

4. The method according to claim 1, wherein the wide or lateral faces of the workpiece are printed on in a number of passes.

5. The method according to claim 4, wherein the digital printing device is pivoted after printing on one of the wide or lateral faces of the workpiece.

6. The method according to claim 1, wherein the machine comprises a number of digital printing devices for printing on the wide or lateral faces of the workpiece.

7. The method according to claim 6, wherein the machine comprises at least four digital printing devices, wherein two of the digital printing devices are configured to print on in each case one of the wide faces of the workpiece and two of the digital printing devices are configured to print on in each case one of the lateral faces of the workpiece.

8. The method according to claim 6, wherein the relative movement is a movement of the workpiece and that a change of direction takes place as the workpiece passes through the machine.

9. The method according to claim 1, wherein the workpiece, at least in sections, consists of wood or wood-based materials.

10. A machine for printing on a panel-like workpiece, which has wide faces and lateral faces, comprising: at least one digital printing device; and a device for bringing about a relative movement between the workpiece and the at least one digital printing device, wherein the machine is configured to print on at least one of the wide faces and at least one of the lateral faces of the workpiece.

11. The machine according to claim 10, wherein the at least one digital printing device is pivotable.

12. The machine according to claim 10, wherein the machine comprises a number of digital printing devices for printing on the wide or lateral faces of the workpiece.

13. The machine according to claim 10, wherein the machine comprises at least four digital printing devices, wherein two of the digital printing devices are configured to print on in each case one of the wide faces of the workpiece and two of the digital printing devices are configured to print on in each case one of the lateral faces of the workpiece.

14. The machine according to claim 10, further comprising a device for rotating the workpiece.

15. The machine according to claim 10, further comprising a conveyor system in order to bring about a relative movement between the workpiece and the at least one digital printing device.

16. The method according to claim 1, wherein the at least one digital printing device is an inkjet printing device.

17. The method according to claim 3, wherein the conveyor system is a conveyor belt or one or more transport belts.

18. The machine according to claim 10, wherein the at least one digital printing device is an inkjet printing device.

19. The machine according to claim 14, wherein the device for rotating the workpiece is configured to rotate the workpiece through 180°.

20. The machine according to claim 15, wherein the machine comprises a device for bringing about a change of direction of the workpiece.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG. 1 shows a schematic view of a process flow in accordance with a first embodiment.

[0029] FIG. 2 shows a process flow in accordance with a second embodiment.

[0030] FIG. 3 shows a process flow in accordance with a third embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] The invention is described by way of example with the help of the attached figures, which show schematic embodiments for process flows. Although the embodiments that are described are intended as examples and have no limiting effect, possible embodiments can also be drawn upon to provide details of the invention. Moreover, individual features or modifications thereof can be used in another embodiment to form additional embodiments that are not described in detail.

[0032] The method described hereafter is used for printing on a number of, preferably all, faces of a panel-like workpiece. An inkjet printing device is used for this purpose. The workpiece to be printed on is a panel-like workpiece which has two wide faces and a number of lateral faces. The lateral faces are also referred to as narrow faces.

[0033] Sections of the workpiece that is processed as part of the methods described below comprise wood or a wood-based material. In particular, it can b e a kitchen worktop, a piece of furniture, a floor panel, a ceiling panel, a panel for use in the structural components industry, or the like.

[0034] The printing device described in the embodiments is an inkjet printing device which comprises a plurality of individually controllable nozzles, through which a printing medium is expelled.

First Embodiment

[0035] In the process flow illustrated in FIG. 1, the workpiece W is moved in a conveying direction by means of a conveyor system 20. In the embodiment example, the conveyor system is a circular conveyor belt, at least sections of which extend through the machine. By means of the conveyor system 20, the workpiece W is moved into the range of a printing device 10, which in a first process flow is arranged in such a way that a wide face of the workpiece is printed on. A full-surface printing process is employed here, so that a color is applied to the entire wide face of the workpiece.

[0036] Once the workpiece W has passed through the machine in a first pass, the workpiece is removed from the conveyor system 20 or is moved back to the entrance to the machine by a return mechanism (not shown). In a second pass, the printing device 10 is first pivoted through 90°, so that the printing device 10 is configured to print on a narrow face of the workpiece W.

[0037] Since the printing device 10 is equipped with a plurality of nozzles, each of which is individually controllable, it is possible to vary the application amount, and hence the application thickness, of the printing device 10 and hence to use the printing device 10 for both the full-surface coating of the wide face and the full-surface coating of the narrow face.

[0038] Once the workpiece W has been moved through the machine in a second pass, the workpiece W can be moved back to the infeed manually or by means of an appropriate return device, so that a further narrow face can be printed on. This process is continued until all faces of the workpiece W have been printed on in the machine.

Second Embodiment

[0039] An example of a process flow for printing on a workpiece W is illustrated in schematic form in FIG. 2. The machine used for this process flow is characterized in that it comprises a plurality of printing devices, which are arranged in the machine.

[0040] The workpiece W is first moved by a conveyor system in a transport direction (step S1) and guided into the range of a first printing device 10-1. The first printing device 10-1 is configured to print on the entire surface of a wide face of the workpiece W.

[0041] The workpiece is then rotated through 180°, so that the second wide face of the workpiece W can be printed on by means of a second printing device 10-2 (step S2).

[0042] The workpiece W is then guided by the conveyor system into the range of a third printing device 10-3, which is configured to print on a narrow face of the workpiece (step S4). The printing in step S4 is also carried out in a pass. The workpiece W is then transported onwards (step S5), and a further narrow face (opposite the above-mentioned narrow face) is then printed on by a fourth printing device 10-4.

[0043] In a further step, the workpiece W is transported in a transport direction changed by 90° in relation to the original transport direction (step S7) and is guided into the range of a fifth printing device 10-5 (step S8). Then, after being transported onwards, a final narrow face of the workpiece W is printed on.

Third Embodiment

[0044] FIG. 3 shows a third embodiment of a method according to the invention. First of all, the workpiece W is moved in a first conveyor system (step S1′) and is then printed on in the region of a first wide face by means of a first printing device 10-la (step S2′).

[0045] In a further transport operation, the workpiece W enters the range of a second printing device 10-2a, which is configured to print on opposing narrow faces of the workpiece moved by the conveyor system (step S3′).

[0046] After being transported onwards (step S4′), the workpiece W is moved in a second conveyor system, which is designed substantially at right angles to the first convey or system. In this way, the workpiece W enters the range of a third printing device 10-3a, which is configured to refine the opposing narrow faces of the workpiece that have not yet been printed on (steps S5′, S6′).

[0047] After the workpiece has been rotated through 180°, it enters the range of a fourth printing device 10-4a, which is configured to print on a second wide face of the workpiece W (step S7′). Transporting the workpiece W within the machine ensures that the first wide face of the workpiece W, which was printed on in step S2′, is already dry, so that when the workpiece is rotated through 180°, the already printed surface of the workpiece W is not damaged.