Orienting device for orienting a workpiece, printing device, and method for orienting a workpiece

Abstract

The invention relates to an orienting device (15) for orienting a workpiece (12), which preferably consists at least in sections of wood, wood-based material, plastic or the like, having an orienting section (16) which is set up to orient the workpiece (12) through contact with a workpiece surface, in particular a narrow surface (13) of the workpiece (12), with respect to a direction of movement (R) of the workpiece (12), the orienting section (16) having at least one contact element (17) which forms a point-shaped and / or linear contact region (20). The invention also relates to a printing device (10) and to a method for orienting a workpiece (12).

Description

[0001] Alignment device for aligning a workpiece, printing device and method for aligning a

[0002] WORKPIECE

[0003] Technical area

[0004] The invention relates to an alignment device for aligning a workpiece, a printing device and a method for aligning a workpiece.

[0005] State of the art

[0006] Workpieces made of wood, wood-based materials, plastic, or similar materials are often used to manufacture furniture parts or other construction elements. Such workpieces can be, for example, particle boards or fiberboards, whose wide and / or narrow surfaces are coated with a coating material for aesthetic and functional reasons and are usually provided with a decorative or surface coating. Before applying the decorative or surface coating, it is also important to avoid even the slightest contamination, static charges, or similar on the workpiece, as these could impair its visual appearance.

[0007] Description of the invention

[0008] The invention is based on the object of proposing an alignment device, a printing device and a method for aligning a workpiece, by means of which high-quality printing of a workpiece is possible in order to achieve an optically high-quality printing result.

[0009] An alignment device is defined in claim 1. A printing device is defined in claim 9. A method is defined in claim 10. Subclaims relate to specific embodiments.

[0010] The invention is based on the knowledge that one of the main causes of impairment of a printing and / or coating process lies in contamination, unwanted static charge, surface tension or the like of a surface of the workpiece to be printed. To achieve an optimal printing result, the surfaces to be printed are pre-treated, which can include both the removal of dust, grease, oil or the like and measures to increase the polar surface energy, for example by plasma treatment, corona treatment or flame treatment. After pre-treatment and before printing, in order to achieve an optimal printing result, it must be ensured that the pre-treated surface does not become even slightly dirty again and / or does not experience any change in surface energy, which can inevitably occur, for example, through contact with machine components.

[0011] Against this background, the invention provides that a generic alignment device for aligning a workpiece, which preferably consists at least in sections of wood, wood-based material, plastic or the like, has an alignment section which is designed to align the workpiece with respect to a direction of movement of the workpiece by contact with a workpiece surface, in particular a narrow surface of the workpiece, wherein the alignment section has at least one contact element which forms a point-shaped and / or linear contact area. Such an alignment device ensures that the pre-treated workpiece surface, in particular the narrow surface of the workpiece, is not affected by the pre-treatment or is only affected to a minimal extent by the alignment by the alignment device.This is achieved in that the at least one contact element only forms the point-shaped and / or linear contact area, so that the workpiece moving in the direction of movement along the alignment section is only contacted by the contact element in a small partial area of ​​the workpiece surface, i.e. in a minimal area which extends linearly along the workpiece surface due to the movement of the workpiece. In other words, the contact area between the at least one contact element and the workpiece surface can tend towards zero by a correspondingly small design of the point-shaped and / or linear contact area. The linear contact area formed by the at least one contact element is aligned in particular parallel to a plane of extension of the workpiece or parallel to the direction of movement.Such a contact element ensures only linear contact with the workpiece surface due to the movement of the workpiece relative to the at least one contact element. The point-like or linear contact area thus ensures minimal contact with the entire workpiece surface, thus minimizing the impact on the pretreatment.

[0012] In a further development of the alignment device, the contact region formed by the at least one contact element can have a cross section, a length and / or a width of approximately 2 mm or less, preferably approximately 1 mm or less, particularly preferably approximately 0.5 mm or less. Such a dimension can form a contact region of the at least one contact element which provides a particularly small contact surface for aligning the workpiece. The term “approximately” can be understood to mean a deviation from the stated value of + / - 10%. For example, the contact region can have a cross section, a length and / or a width of approximately 0.2 mm or less. The value of approximately 0.2 mm can therefore be in the range from 0.18 mm (-10%) to 0.22 mm (+10%).

[0013] A further embodiment of the alignment device can provide that the contact region formed by the at least one contact element has a cross section, a length and / or a width of approximately 20% or less, preferably approximately 10% or less, particularly preferably approximately 5% or less, of a workpiece thickness of the workpiece to be aligned.

[0014] In this way, the dimension of the contact region of the at least one contact element can be designed to be as minimal as possible in relation to a dimension of the workpiece to be aligned, in particular a thickness of the workpiece, i.e. a width of the narrow surface. For example, the contact region can also have a cross-section, a length and / or a width of approximately 1% or less of the workpiece thickness of the workpiece. A lower limit of the dimension of the contact region can be limited in particular by a mechanical strength of the contact element.

[0015] Particularly advantageously, the alignment device can be provided with at least one contact element in the form of a contact roller having different outer diameters, with an outermost outer circumference of the contact roller forming the contact area. Such a contact roller rolls along the workpiece surface to align the workpiece, while the workpiece moves in the direction of movement along the alignment section. The contact roller is provided in a fixed location, while the workpiece moves with the workpiece surface along the at least one contact roller.

[0016] By having at least one contact roller having different outer diameters and the outermost outer circumference of the contact roller forming the contact area, it is easy to form the smallest possible contact area. In this way, the contact area of ​​the at least one contact roller can be formed by only a partial section of a surface line of the surface of the contact roller. For example, the contact roller can form a surface which, in a longitudinal section of the contact roller, has a conically running surface line, a doubly counter-conical surface line, a convex surface line or the like, so that the contact roller has an outermost outer circumference which forms the contact area.

[0017] In an alternative embodiment, the at least one contact element can be designed as a disc-shaped contact roller. The disc-shaped contact roller can have the thinnest possible design. For example, the disc-shaped contact roller can have a thickness of approximately 2 mm or less, preferably approximately 1 mm or less, particularly preferably approximately 0.5 mm or less.

[0018] Alternatively or additionally, the contact element can also be designed, for example, in the form of a band, a strip and / or a thread.

[0019] Likewise, the disc-shaped contact roller may have a thickness of about 20% or less, preferably about 10% or less, particularly preferably about 5% or less, of the workpiece thickness of the workpiece to be aligned.

[0020] In a preferred development of the alignment device, the at least one contact roller can form a surface which has a conical, roof-shaped, convex, spherical and / or groove-shaped surface line with respect to a rotational axis.

[0021] The surface line forms the outer contour of the surface. This means that the surface line is formed in a longitudinal section through the outer side of the contact roller, which forms the surface. As the surface line is conical, roof-shaped, convex, crowned and / or grooved with respect to the rotational axis of the contact roller, the contact roller has an outermost circumference which forms the point-like contact area. In other words, in order to align the workpiece, the contact roller only contacts the workpiece surface with a minimal section of the surface line in the area of ​​the outermost circumference.

[0022] An embodiment of the alignment device can also provide that a plurality of contact elements are provided, each of which forms a contact area, wherein the contact areas of the plurality of contact elements are arranged in alignment with one another in an alignment direction.

[0023] In particular, the alignment section comprises a plurality of contact rollers arranged corresponding to one another, the respective contact regions of which are aligned with one another. The contact rollers preferably have an identical design. In this way, a point-shaped contact region can be formed by each contact element, wherein the contact regions together form the alignment section in an alignment direction. In this case, the workpiece moving in the direction of movement towards the contact elements is contacted along the workpiece surface only in the form of a linear, preferably needle-line-shaped, contact by the contact elements.

[0024] Advantageously, the alignment device can have a pretreatment device for carrying out one or more pretreatment steps on the workpiece surface, in particular a narrow surface, wherein the pretreatment device is arranged downstream of the alignment section in the direction of movement of the workpiece and preferably comprises a pre-cleaning unit, degreasing unit, unit for improving the adhesion and wetting properties and / or unit for reducing the electrical (in particular electrostatic) charge.

[0025] The pretreatment device can preferably be aligned correspondingly to the at least one contact element. For example, the pretreatment device can be configured to pretreat the workpiece surface, in particular the narrow surface, only in the area contacted by the at least one contact element. In this way, a reduced cleaning requirement, in particular a reduced consumption of process materials, e.g., auxiliary materials and consumables, can be achieved, since these only need to be applied in the area of ​​contact of the alignment elements.

[0026] In particular, the alignment device can be provided to align the workpiece for a subsequent processing operation, in particular printing and / or coating, of the workpiece surface, in particular the narrow surface of the workpiece.

[0027] The printing can preferably provide that the workpiece surface, in particular the narrow surface, is printed with printing ink by a printing unit, for example an inkjet printing unit, or that surface varnish is applied to the workpiece surface.

[0028] A particularly advantageous application of the alignment device according to the invention is, according to a further development of the invention, a printing device according to claim 9. In such a printing device, the advantages described above unfold their full effect, since such printing devices require defined physical properties of the workpiece surface to be printed in order to achieve an optimal printing result.A printing device according to the invention provides that at least one printing unit is provided for applying a printing ink and / or surface coating to at least one workpiece surface, in particular a narrow surface of the workpiece, a transport device for bringing about a transport movement of the workpiece relative to the printing unit and at least one alignment device, wherein the alignment device is arranged upstream of the printing unit and is set up to align the workpiece by means of the transport movement, wherein the alignment device is designed according to one of the preceding claims.

[0029] A method for aligning a workpiece is defined in claim 10 and serves to realize the above-mentioned advantages. The method provides that a movement of the workpiece is brought about relative to an alignment device, wherein a workpiece surface, in particular a narrow surface of the workpiece, is brought into contact with at least one contact element of the alignment device, and the workpiece is aligned with respect to the direction of movement of the workpiece by moving the workpiece surface, in particular a narrow surface of the workpiece, along the at least one contact element, wherein the workpiece surface, in particular a narrow surface of the workpiece, is contacted by a point-shaped and / or linear contact region of the at least one contact element. Brief description of the drawings

[0030] Further features and advantages of a device, a use and / or a method will become apparent from the following description of embodiments with reference to the accompanying drawings. These drawings show:

[0031] Fig. 1 is a schematic plan view of an embodiment of a printing device according to the disclosure;

[0032] Fig. 2 is a schematic side view of the printing device in Fig. 1;

[0033] Fig. 3 is a schematic perspective view of an embodiment of an alignment device according to the disclosure of the printing device in Fig. 1;

[0034] Fig. 4 is a schematic detailed view of several contact elements of the alignment device according to detail A in Fig. 3;

[0035] Description of embodiments

[0036] The same reference symbols appearing in different figures indicate identical, corresponding, or functionally similar elements.

[0037] Fig. 1 shows a schematic plan view of a printing device 10 and Fig. 2 shows a schematic side view of the printing device 10.

[0038] The printing device 10 comprises a printing unit 11 for applying a printing ink and / or a surface coating, for example a surface varnish, to a workpiece 12. In particular, the printing unit 11 is designed to print a narrow surface 13 of the workpiece 12 with the printing ink and / or the surface coating. The narrow surface 13 can be provided with a coating material, for example an edge band. The edge band can advantageously be made of an antistatic material, for example.

[0039] The workpiece 12 is, in particular, a workpiece that consists at least in sections of wood, wood-based material, plastic, or the like. The workpiece 12 is preferably designed as a plate-shaped workpiece, for example, as a solid wood panel, chipboard, fiberboard, or the like. Such workpieces 12 can be intended, for example, for the production of furniture or building elements.

[0040] The printing unit 11 is preferably designed as an inkjet printing unit. The printing unit 11 can have one or more print heads (not shown in detail) for dispensing the printing ink and / or surface coating. The printing unit 11 preferably carries out an inkjet printing process. In particular, the printing unit 11 is a digital printing unit.

[0041] The printing device 10 additionally comprises a transport device 14 for transporting the workpiece 12 in a direction of movement R relative to the printing unit 11. The transport device 14 can be, for example, a conveyor belt, a conveyor chain or the like. Preferably, the transport device 14 forms a support surface on which the workpiece 12 to be printed rests during the transport movement. In particular, the workpiece 12 rests loosely on the transport device 14 so that an alignment of the workpiece 12 to the printing unit 11 as described below is possible for the printing process. A large number of workpieces 12 can be transported successively relative to the printing unit 11 by means of the transport device 14. The printing device 10 can be designed as a through-feed device by means of the transport device 14.

[0042] For aligning the workpiece 12 relative to the printing unit 11, the printing device 10 comprises an alignment device 15. The alignment device 15 is configured to align the workpiece 12 with respect to the direction of movement R by contact with the narrow surface 13 of the workpiece 12.

[0043] For this purpose, the alignment device 15 comprises an alignment section 16 which comprises a plurality of contact elements 17. The alignment device 15 preferably comprises a carrier 18 on which the contact elements 17 are arranged. The contact elements 17 are provided in order to be brought into contact with the narrow surface 13 in order to align the workpiece 12. For this purpose, the workpiece 12, which is lying loosely and possibly crookedly on the transport device 14, is brought into contact with the contact elements 17 due to the transport movement and is aligned parallel to these during the movement by this contact, i.e. aligned with the narrow surface 13 in the direction of movement R.

[0044] Fig. 3 shows a schematic perspective view of the alignment device 15 and Fig. 4 shows a schematic detailed view of several contact elements 17 of the alignment device 15 according to detail A in Fig. 3.

[0045] The plurality of contact elements 17 are arranged on the carrier 18 so as to correspond to one another along the direction of movement R. As can be seen from Figs. 3 and 4, the contact elements 17 are each designed as a contact roller 19. The contact rollers 19 preferably have an identical configuration. Each contact roller 19 forms a contact region 20 on an outermost circumference 21 of the respective contact roller 19, wherein the contact regions 20 of the contact rollers 19 are aligned with one another in the direction of movement R. In this way, the workpiece 12 can be brought into contact with the narrow surface 13 with the contact regions 20 of each contact roller 19.

[0046] Each contact roller 19 has a design in which a circumferential surface 22 of the contact roller 19 is formed by at least two different outer diameters. This ensures that the contact rollers 19 do not roll along the narrow surface 13 with their entire circumferential surface 22, which would create a large contact area, but rather only roll along the narrow surface 13 with a portion of the circumferential surface 22, the contact area 20.

[0047] According to the embodiment shown in Figs. 3 and 4, the contact rollers 19 have a conical shape. In other words, in a longitudinal section along a rotational axis 23 of the contact roller 19, the outer surface 22 forms a conical or tapered surface line 24, with the outermost outer circumference 21 of the outer surface 22 forming the contact area 20.

[0048] However, the contact rollers 19 are not limited to such a conical or tapered configuration. The contact rollers 19 can also have a surface 22 that has a roof-shaped, convex, spherical, or grooved surface line 24 with respect to the rotational axis 23, with the outermost outer circumference 21 of the contact roller 19 forming the contact area 20.

[0049] Preferably, each contact roller 19 forms a contact point or a point-shaped contact region 20. This contact region 20 has a dimension with a cross-section, a length and / or a width of approximately 2 mm or less, preferably approximately 1 mm or less, particularly preferably approximately 0.5 mm or less.

[0050] This makes it clear that the contact rollers 19 contact only a minimal area in relation to the dimension of the narrow surface 13, which may, for example, have a width of approximately 10 mm to 50 mm or more (i.e., a thickness of the workpiece 12 of approximately 10 mm to 50 mm or more), in order to align the workpiece 12.

[0051] In an alternative embodiment, the contact rollers 19 can also be designed as disc-shaped contact rollers 19. Such disc-shaped contact rollers 19 can be designed to be particularly thin, for example with a thickness of approximately 2 mm or less, preferably approximately 1 mm or less, particularly preferably approximately 0.5 mm or less, so that a minimal contact area 20 is already formed by the outer surface 22 as such.

[0052] The contact rollers 19 can also be designed such that the dimensions of the contact regions 20 are determined in relation to the workpiece dimensions. For example, the contact region 20 formed by the contact roller 19 can have a cross-section, a length, and / or a width of approximately 20% or less, preferably approximately 10% or less, particularly preferably approximately 5% or less, of the thickness of the workpiece 12 to be aligned (i.e., the width of the narrow surface 13).

[0053] The printing device 10 also has a pretreatment device 25 for performing one or more pretreatment steps on the narrow surface 13 of the workpiece 12. This pretreatment device 25 can, for example, comprise a pre-cleaning unit, a degreasing unit, a unit for improving the adhesion and wetting properties, and / or a unit for reducing electrical charging.

[0054] The pretreatment device 25 is arranged downstream of the alignment section 16 of the alignment device 15 and upstream of the printing unit 11 in the direction of movement R of the workpiece 12. The pretreatment device 25 can be provided as a component of the alignment device 15. For example, the pretreatment device 25 can be arranged adjacent to the alignment section 16 on the carrier 18.

[0055] The pretreatment device 25 can preferably be designed such that the pretreatment of the narrow surface 13 takes place only in the area contacted by the contact rollers 19. In this way, pretreatment expenditure, for example the use of process and cleaning agents, after the alignment of the workpiece can be minimized.

[0056] It will be apparent to those skilled in the art that individual features described in different embodiments may also be implemented in a single embodiment, provided they are not structurally incompatible. Likewise, various features described in a single embodiment may also be provided in multiple embodiments, individually or in any suitable subcombination.

Claims

CLAIMS 1. Alignment device (15) for aligning a workpiece (12), which preferably consists at least in sections of wood, wood-based material, plastic or the like, comprising an alignment section (16) which is designed to align the workpiece (12) by contact with a workpiece surface, in particular a narrow surface (13) of the workpiece (12), with respect to a direction of movement (R) of the workpiece (12), wherein the alignment section (16) has at least one contact element (17) which forms a point-shaped and / or linear contact region (20).

2. Alignment device according to claim 1, wherein the contact region (20) formed by the at least one contact element (17) further has a cross section, a length and / or a width of approximately 2 mm or less, preferably approximately 1 mm or less, particularly preferably approximately 0.5 mm or less.

3. Alignment device according to claim 1 or 2, wherein the contact region (20) formed by the at least one contact element (17) further has a cross section, a length and / or a width of approximately 20% or less, preferably approximately 10% or less, particularly preferably approximately 5% or less, of a workpiece thickness of the workpiece (12) to be aligned.

4. Alignment device according to one of the preceding claims, wherein the at least one contact element (17) is further designed as a contact roller (19) having different outer diameters, wherein an outermost outer circumference (21) of the contact roller (19) forms the contact area (20), and / or is designed as a disc-shaped contact roller (19).

5. Alignment device according to claim 4, wherein the at least one contact roller (19) further forms a lateral surface (22) which has a conical, roof-shaped, convex, spherical and / or groove-shaped surface line (24) with respect to an axis of rotation (23).

6. Alignment device according to one of the preceding claims, in which a plurality of contact elements (17) are further provided, each forming a contact region (20), wherein the contact regions (20) of the plurality of contact elements (17) are arranged in alignment with one another in an alignment direction.

7. Alignment device according to one of the preceding claims, in which a pretreatment device (25) is further provided for carrying out one or more pretreatment steps on the workpiece surface, in particular narrow surface (13), wherein the pretreatment device (25) is arranged downstream of the alignment section (16) in the direction of movement (R) of the workpiece (12) and preferably comprises a pre-cleaning unit, degreasing unit, unit for improving the adhesion and wetting properties and / or unit for reducing the electrical charge.

8. Alignment device according to one of the preceding claims, in which the alignment device (15) is further provided in order to align the workpiece (12) for a subsequent processing operation, in particular printing and / or coating, of the workpiece surface, in particular narrow surface (13) of the workpiece (12).

9. Printing device (10) for printing and / or coating a workpiece (12), which preferably consists at least in sections of wood, wood material, plastic or the like, comprising at least one printing unit (11) for applying a printing ink and / or surface coating to at least one workpiece surface, in particular a narrow surface (13) of the workpiece (12), a transport device (14) for bringing about a transport movement of the workpiece (12) relative to the printing unit (11) and at least one Alignment device (15), wherein the alignment device (15) is arranged upstream of the printing unit (11) and is configured to align the workpiece (12) by the transport movement, wherein the alignment device (15) is designed according to one of the preceding claims.

10. A method for aligning a workpiece (12), which preferably consists at least in sections of wood, wood material, plastic or the like, in particular with an aligning device (15) according to one of claims 1 to 8, comprising the steps: bringing about a movement of the workpiece (12) relative to an aligning device (15), wherein a workpiece surface, in particular a narrow surface (13) of the workpiece (12), is brought into contact with at least one contact element (17) of the aligning device (15), aligning the workpiece (12) with respect to the direction of movement (R) of the workpiece (12) by moving the workpiece surface, in particular a narrow surface (13) of the workpiece (12), along the at least one contact element (17), wherein the workpiece surface, in particular a narrow surface (13) of the workpiece (12), is contacted by a punctiform and / or linear contact area (20) of the at least one contact element (17).

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