EP1837189B1 - Device for refining of workpieces - Google Patents

Description

Technical area

The invention relates to a device for refining workpieces, which are preferably at least partially made of wood, wood-based materials or the like, according to the preamble of claim 1.

State of the art

A device of the type mentioned is, for example, from the DE 100 31 030 B4 known. In this device, workpieces are delivered and stored on a conveyor. In order to detect the positioning of the workpieces on the conveyor, the apparatus has stationary sensors mounted on the conveyor or on a gantry. These sensors must also detect the geometry of the workpieces, or the geometry data must be transferred from an upstream processing machine and read and transformed by the sensors taking into account the new positioning data. This leads to a high constructive and procedural effort.

Furthermore, the filed by the Applicant, post-published European patent application EP 05 009 326.9 also a device with a printing device, a workpiece support device and a conveying device, as these devices are reproduced in the preamble of claim 1.

EP 1 479 524 A1 shows an ink jet printing device, which is located above a transport plate, and which includes an ink jet head, which is pivotable on an arm about an axis and which can be telescoped. To control the printhead, an electronic control unit is provided which contains a microprocessor with associated program and data memory. Outputs of the controller are connected to the print head and various drive means for the pivoting movement and the telescopic displacement of the printing device. This makes it possible to move the inkjet printhead relative to a base body below it such that the printhead can reach the entire surface of the chrome body.

DE 100 31 030 A1 discloses a method for producing sheet-like components with a predetermined surface appearance, in particular front panels of kitchen elements. For this purpose, a crossbeam is arranged above a conveyor with a moving conveyor belt on which a carriage is movably guided. On the carriage, a print head is attached to which liquid can be sprayed by ink nozzles.

The doctrine of US 2003/218663 A1 Aim to a method and apparatus for generating an image on a product. The printing device itself is stationarily arranged on a transport device and comprises a printer which has at least one print head and is connected to a control device. The controller includes an image processor to generate the image to be applied to the product

DE 20 2004 000662 U1 discloses a printing device for printing on the narrow sides of plate-shaped workpieces.

The doctrine of EP 0 993 903 A2 refers to a machine for processing wood products. This machine includes a tool holder which is movably mounted on bearing means. The machine has a portal with two upwardly directed struts along which a beam can move. On both sides of the bar tool holding heads are arranged, which can slide on these beams. In these tool holding heads, an inkjet marking tool can be installed.

Presentation of the invention

It is therefore an object of the present invention to provide a generic device for finishing workpieces, which allows a high quality finishing with simple design and easy operation.

This object is achieved by a device for finishing workpieces according to claim 1. An advantageous development of the invention is specified in claim 2.

The invention is based on the idea to avoid the re-clamping of the workpieces to be finished in the course of finishing as much as possible. For this purpose, it is provided according to the invention in a generic device that it further comprises at least one processing device for processing the workpiece. In this way, it is possible not only to print the workpieces in the device according to the invention, but also to carry out individual or numerous machining operations, which can be before, after or even temporarily stored for printing. As a result, can be dispensed with a re-clamping between these finishing steps, so that no multiple workpiece alignment and / or sensor detection is required, which simplifies the construction of the overall device and its operation, without affecting the finishing quality.

Although the use of at least one ink-jet printing device is preferred within the scope of the invention, other printing devices may alternatively or additionally be used.

In the context of the invention, it is in principle possible to arrange the ink-jet printing device and / or the processing device stationary and to be finished workpieces feed this along using the conveyor along. It is likewise possible to make the printing device and / or the machining device movable or to provide a combination of both variants, ie that both the workpieces and the printing device and / or the machining device are moved during the printing or machining operation using the conveying device ,

In the context of the present invention, the processing device for processing the workpiece can be configured in a wide variety of ways and designed for one or more types of processing.

In the context of the present invention, the conveyor device can also be designed in many different ways, for example by a single workpiece conveyor table, but also by a multiplicity of movable components which can be moved in relation to one another. According to one embodiment of the invention, however, it is preferred that the conveying device is set up to bring about a relative movement between the workpiece to be finished and the processing device, preferably in such a way that the workpiece can be processed and printed without changing its relative position to the workpiece carrier device. In this way, a re-clamping of the workpieces to be finished in the course of finishing in the device according to the invention can be avoided, resulting in a simple and precise operation with high quality finishing.

The ink-jet printing device and the processing device can in principle be placed anywhere in the device according to the invention, for example also on a movable or stationary robot.

According to the invention, the printing device is received einwechselbar in a spindle unit.

Such a spindle unit is very well suited as a basic component of a processing device, in a combination with a plurality of Machining tools and / or aggregates, which are interchangeable according to the invention in the at least one spindle unit and can be stored in at least one magazine. This results in low design effort, such as a small number of drives, a wide variety of processing options for the workpieces.

In addition, the at least one spindle unit will not only be used for operating a wide variety of machining tools and / or assemblies, but also for operating a printing unit. For this purpose, according to the invention mentioned in claim 1, the printing unit is provided, which is einwechselbar in the at least one spindle unit, via an interface. In this way, the printing unit can also be used flexibly and only brought into an operating position in the spindle unit when it is needed for finishing the workpiece. In order to enable a safe replacement of the printing unit in the spindle unit, it is provided according to the invention that the printing unit has connection means by means of which it is exchangeable in the tool holder of a spindle unit. Thus, the spindle unit does not have to be adapted to accommodate the printing unit, but the printing unit has suitable connection means which can be included in the already existing tool holder of the spindle unit.

Brief description of the drawings

Fig. 1

shows schematically a perspective view of a device for finishing workpieces according to an embodiment of the invention;

Fig. 2

schematically shows a partial plan view of the in Fig. 1 shown device;

Fig. 3

schematically shows a partially sectioned front view of in Fig. 1 shown device;

Fig. 4

shows more details of the printing device in Fig. 1 shown device;

Fig. 5

shows further details of the printing device in Fig. 1 shown device;

Fig. 6

illustrates the operation of in Fig. 1 shown device.

Detailed description of preferred embodiments

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

An apparatus 1 for refining workpieces as a preferred embodiment of the present invention is disclosed in US Pat Fig. 1 shown schematically in a perspective view. The device is used for processing and patterning of workpieces 2, which in the present embodiment at least partially made of wood, wood materials, plastics or the like, as they are often used for example in the field of furniture and components.

The device 1 comprises an ink-jet printing device 10, which operates in the present embodiment according to the drop-on-demand principle. As in Fig. 4 As best seen, the ink-jet printing device 10 includes a plurality of nozzles 12 from which ink droplets may be ejected and which are arranged in a plurality of rows in the present embodiment, each row being for ejecting a predetermined color, for example the colors cyan, magenta, yellow and black.

Furthermore, drying units 14, for example UV dryers, are provided on the printing device 10, which serve to rapidly increase the ink applied by the printing device dry to prevent possible printing with inaccurate "passer".

The printing device 10 is provided in the present embodiment on a spindle unit 6 or in this changed, which in Fig. 3 best seen. The spindle unit is such a spindle unit which is also suitable for receiving and exchangeable receiving of machining tools or processing units and which for this purpose has a tool holder 6 'and an interface 6 ", wherein the interface can be used, for example, for transmitting data, Energy, drive, fluids, etc. can be designed ..

In order to enable the replacement of the printing device (printing unit) 10 in the spindle unit, the printing unit 10 is provided in the present embodiment with a connecting piece 18 which is einwechselbar in the tool holder 6 'of the spindle unit (see. Fig. 3 ). Furthermore, the printing unit 10 has transmission means 16 (cf. Fig. 3 For example, data, energy, drive, fluids, etc., and in particular ink, may also be transferred, and the printing unit 10 may include an ink supply and / or a wireless data transfer device, although this may be the case not shown in the figures.

The spindle unit 6 is provided in the y-direction movable on a portal 4, which in turn can be designed to be movable in the x-direction. In this case, two portals 4 are provided in the present embodiment, each of which may carry one or more spindle units 6, which may optionally be arranged on opposite sides of the respective portal 4. It should be noted that the portals 4 may optionally be designed as a boom.

The spindle units 6 can be automatically or manually equipped with processing tools and / or processing units 30 and one or more printing units 10 via tool magazines 32 respectively provided on the portals 4 (FIG. Fig. 3 ). D. h., The printing units 10 are configured such that they can also be stored in the magazines 32.

In the context of the present embodiment, a very wide variety of processing tools 30 and / or processing units 30 can be used; such as cutting tools (drills, milling cutters, etc.), Kantenanleimaggregate, Extrudieraggregate, coating units, laminating units, cleaning units, degreasing units, aggregates to improve the adhesion and wetting properties of the surfaces to be printed and units for reducing the electrostatic charge of the surfaces to be printed. Of course, these tools and units can also be fixed (independent of a spindle unit). To perform the types of cleaning, degreasing, improving the adhesion and wetting properties and reduction of the electrostatic charge is applied to the filed by the Applicant European Patent Application No. 06 004 713.1 whose priority is claimed.

Below the gantries 4 extends in the present embodiment, a workpiece table 20 for supporting the respective to be sampled workpieces 2, which in the in Fig. 1 shown x-direction is movable. The workpiece table 20 can be designed in various ways and, for example, also be formed by a circulating conveyor belt or the like. The workpiece table 20 forms by its movability at the same time Workpiece carrier and a part of the conveyor device according to the present invention.

The arrangement of a plate-shaped workpiece 2 on the workpiece table 20 is in Fig. 2 shown in more detail in a plan view. In the present embodiment, the workpiece table 20 has extendable stop bolts 22, to which the workpiece 2 can be applied for coarse positioning. Further, a plurality of distance sensors 52 are arranged on the workpiece table 20, which are part of a coarse detection device 50. In the Fig. 2 Distance sensors shown are arranged to detect the distance between the sensors and a side surface (narrow surface) of the respective workpiece 2. In this case, the sensors 52 in the present embodiment are rotatable about an axis extending orthogonally to the surface of the workpiece table 20 and optionally movable parallel to the surface. The coarse detection device 50 thus serves for coarse detection of the geometry and positioning of the respective workpiece 2.

Further details of the workpiece table 20 are in Fig. 3 shown a partially sectioned front view of the in Fig. 1 shown device shows. There, it can be seen that the respective workpiece 2 can be fixed on the workpiece table 20, for example via vacuum cups 24. It is also possible to integrate corresponding suction or suction openings in the workpiece table or a workpiece band.

Furthermore, the device 1 according to the invention comprises a detection device 40 for detecting the relative position of the ink-jet printing device 10 and the respective surface of a workpiece 2 to be patterned. The detection device 40 in the present embodiment has several types of sensors 42, 46 which are arranged in the Figures 3 . 4 and 5 are best seen. First, the detection means 40 in the present Embodiment three distance sensors 42, which are arranged on the pressure device 10 adjacent to the nozzles 12 and measure in a direction which is substantially parallel to the ink ejection direction of the nozzles 12 ( Fig. 4 ). On the one hand, the absolute distance between the pressure device 10 and the workpiece 2 can be determined with these distance sensors, but beyond that, it is also possible to deduce the exact contour of the respective workpiece 2 from the distance data obtained.

As in the Figures 3 and 5 can best be seen, more distance sensors 42 are each arranged on the pressure device 10 via a pivotable element 44 in the present embodiment. By the pivotable element 44 of the respective sensor can be brought into an extended position, the in Fig. 5 best seen. In this position, the in Fig. 5 shown sensors 42 in a direction which is substantially orthogonal to the ink ejection direction of the nozzles 12. As a result, the thickness or height of the respective area to be printed can be detected and an "overspray" avoided.

Moreover, on the printing device 10 adjacent to the ink ejection nozzles 12 in the present embodiment, an image sensing sensor 46 is arranged, which also measures in a direction substantially parallel to the ink ejection direction of the nozzles 12. The image-capturing sensor 46 can be, for example, a CCD camera or the like, which can produce a complete image of a region of the respective workpiece 2 to be printed or already printed.

Although not shown in the figures, on the one hand all sensors and on the other hand the printing device and preferably also the other operating components of the device 1 are connected to a control device which evaluates the respective data detected by the sensors and on this Basis controls the operation of the device, in particular the printing device. The operation of the device can be represented as follows.

First, a workpiece 2 is roughly positioned over the stopper pins 22 on the workpiece table 20 and fixed via the vacuum cups 24. Subsequently, the positioning and / or contour of the workpiece 2 are detected on the workpiece table 20 by the sensors 52 and passed this data to the control device.

The workpiece table 20 is then moved in the x-direction, so that the workpiece 2 can be processed or finished by tools, units or printing units that are inserted into the spindle units 6. In this case, the operation of the printing device takes place, for example, as follows.

On the basis of the data from the sensors 52, the printing device 10 is moved with the corresponding spindle 6 along the portal 4 to the workpiece 2 to be printed. The sensors 42, 46 continuously perform a measuring operation, so that the presence and optionally the distance of the respective workpiece and beyond (by the image detection sensor 46) also further information about the workpiece 2 can be obtained. Based on these data, the controller outputs pressure signals to the respective nozzles 12 (or the associated piezoelectric actuators or thermocouples) so that the workpiece 2 is printed. Depending on the detection data of the sensors 42, 46, individual nozzles or nozzle groups can be switched on or off in order to compensate for dimensional, position or other tolerances or deviations of the workpiece 2. Alternatively or additionally, within the scope of the invention it is equally possible for individual or multiple nozzles of the printing device 10 to be produced via piezo-adjusting means or the like in order to adapt their position or ejection direction to the workpiece 2. When printing a large side surface of a workpiece 2 in addition to the image detection sensor 46 primarily arranged next to the nozzles 12 sensors 42, which work in Fig. 4 are best seen. For printing on a narrow surface of the workpiece 2, alternatively or additionally, the sensors 42 are used, which are extendable via pivotable elements 44 in order to detect the height of the narrow surface and thus to prevent overspray.

After printing on a surface section, it may optionally be dried by the drying units 14, possibly also simultaneously with the printing process.

The travel paths of the printing device 10 and / or the workpiece 2 are in Fig. 6 shown schematically. The left drawing in Fig. 6 shows an operation in the so-called transverse pressure, in which the printing device 10 along with the spindle unit 6 along the portal 4 reciprocates in the y-direction and the workpiece 2 is further clocked by the workpiece table 20 in the x-direction.

Alternatively, it is equally possible that in Fig. 6 Right-hand print scheme used, which can be referred to as longitudinal pressure. In this case, the printing device 10 is substantially stationary during the printing process itself, and the workpiece 2 is reciprocated with the workpiece table 20 in the x-direction. The printing device 10 thus only needs to be clocked in the y-direction after the printing of a web has been completed. In addition, in the context of the present invention, combinations of both operations are possible, and it can be printed, for example, obliquely arranged tracks or the like.

Claims (2)

1. Apparatus (1) for refining workpieces (2) which are preferably at least partially made of wood, derived timber products or the like, having:

   a printing device (10) which is preferably designed as an ink jet printing device having a plurality of jets (12) from which ink droplets can be ejected,

   a workpiece carrying device (20) for carrying the workpiece (2) to be patterned,

   a conveying device for bringing about a relative movement between the workpiece (2) to be refined and the printing device (10), and

   at least one processing device (30) for processing the workpiece,

   wherein the apparatus further comprises a spindle unit having a tool holder (6') for holding processing devices in a manner allowing them to be exchanged,

   characterised in that

   the apparatus has at least one magazine,

   the apparatus further has a plurality of processing tools and/or units (30) which can be inserted in the tool holder of the at least one spindle unit (6) and deposited in the at least one magazine (32), and

   the printing device (10) has connecting means (18) by means of which it can be inserted via an interface (6") in the tool holder (6') of the at least one spindle unit (6).
2. Apparatus according to claim 1, characterised in that the conveying device is designed also to bring about a relative movement between the workpiece (2) to be refined and the processing device (30), this being preferably in such a way that the workpiece (2) can be processed and printed on without changing its position relative to the workpiece carrying device (20).

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