EDGE-COATING A PANEL WITH A COATING MEDIUM

Abstract

The disclosure relates to a coating device for edge-coating a panel with a coating medium, the device comprising at least one medium line, for guiding a coating medium, which comprises an inlet and an outlet, wherein the medium line comprises a recess for introducing a panel into a coating-medium stream, and wherein the medium line and the recess are designed such that the coating medium can be applied to the edge of the panel by means of suction in the flow direction of the medium. The present disclosure also relates to a coating system for edge-coating a panel with a coating medium.

Claims

1. A coating system for edge coating a panel with a coating medium, wherein the system comprises: a medium line system for guiding a coating medium; a pump system connected to the medium line system for conveying the coating medium; and at least one coating device connected to the medium line system, wherein the coating device comprises: at least one medium line for guiding a coating medium, comprising an inlet and an outlet, wherein the medium line comprises a recess for introducing a panel into a coating medium stream, and wherein the medium line and the recess are designed in such a way that the coating medium can be applied onto the edge of the panel by means of suction in the medium flow direction, wherein the pump system comprises a vacuum device arranged downstream of the outlet in the medium flow direction, wherein the vacuum device is configured to generate a negative pressure at the outlet.

2. The coating system according to claim 1, wherein a medium line cross-section of the medium line system is also configured to generate a negative pressure at the outlet.

3. The coating system according to claim 2, wherein a separator system is interconnected in the medium flow direction between the vacuum device and the outlet, wherein the separator system is configured to separate gas supplied from the vacuum device from the coating medium, wherein the separator system comprises a screen system for separatingly filtering the coating medium from the gas, wherein the separator system comprises a lid for making the separator system accessible.

4. The coating system according to claim 3, wherein a pump of the pump system is interconnected in the medium flow direction between the separator system and the inlet, wherein the pump is configured for meterable conveyance of the coating medium up to the inlet.

5. The coating system according to claim 4, wherein the pump is a shear force-free pump, preferably a peristaltic pump, wherein the preferred peristaltic pump comprises a hose comprising chlorosulfonated polyethylene, CSM, wherein in particular the hose consists of CSM.

6. The coating system according to claim 4, wherein the pump, and in particular a medium line cross-section of the medium line system, is configured to convey the coating medium in such a way that the inlet is fed with the coating medium with a supply pressure greater than or equal to the medium pressure at the recess (3c), preferably with a supply pressure greater than or equal to 3.5×10.sup.3 Pa, particularly preferably with a supply pressure of 10.sup.4 Pa to 2×10.sup.4 Pa.

7. The coating system according to claim 3, wherein a heater is interconnected in the medium flow direction between the separator system, in particular between the pump, and the inlet, wherein the heater is configured for heating the coating medium to a temperature in a range from 30° C. to 45° C.

8. The coating system according to claim 1, wherein the panel is a conveyed panel.

9. The coating system according to claim 1, wherein the medium line and the recess are configured in such a way that the coating medium can be applied to the edge of the panel at a medium pressure at the recess in a range from 3.5×10.sup.3 Pa to 5.5×10.sup.3 Pa, preferably at a medium pressure of 5×10.sup.3 Pa.

10. The coating system according to claim 1, wherein the recess and a medium line cross-section have an aspect ratio relative to one another and the medium line extends in such a way that the coating medium can be applied onto the edge of the panel by means of suction in the medium flow direction, in particular that the coating medium can be applied onto the edge of the panel at a medium pressure in a range from 3.5×10.sup.3 Pa to 5.5×10.sup.3 Pa, preferably at a medium pressure of 5×10.sup.3 Pa.

11. The coating system according to claim 1, wherein the recess is arranged at an outer bend of an arc-shaped or bent medium line section, wherein in particular the arc-shaped or bent medium line section has an acute inner angle, wherein in particular an inlet piece, which extends from the inlet to the recess, extends vertically in the state in which the medium line is connected via the inlet.

12. The coating system according to claim 1, wherein the medium line is U-shaped with two legs, wherein in particular the inlet piece is a first leg and an outlet piece extending in the medium flow direction from the recess to the outlet is a second leg.

13. The coating system according claim 1, wherein an edge profile of the recess is configured to be adapted form-fittingly to the edge of the panel, and wherein in particular the edge profile of the recess is configured as a counter profile to a profile of the edge of the panel.

14. The coating system according to claim 1, wherein two medium lines are provided for guiding the coating medium.

15. (canceled)

Description

[0045] FIG. 1 is a schematic view of the coating device according to a preferred exemplary embodiment of the disclosure;

[0046] FIG. 2 is another schematic view of the coating device according to the preferred exemplary embodiment of the disclosure;

[0047] FIG. 3 is a schematic view of a coating system according to a preferred exemplary embodiment of the disclosure;

[0048] FIG. 4 is a schematic view of a coating system according to the prior art; and

[0049] FIG. 5 is a flow chart of an exemplary coating method.

[0050] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

[0051] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0052] The exemplary embodiments described are merely examples that can be modified and/or supplemented in various ways within the scope of the claims. Each feature described for a particular exemplary embodiment may be used independently or in combination with other features in any other exemplary embodiment. Any feature described for an exemplary embodiment of a particular claim category may also be used in a corresponding manner in an exemplary embodiment of another claim category.

[0053] FIG. 1 shows a schematic view of the coating device 1 according to a preferred exemplary embodiment of the disclosure. The coating device 1 is adapted for edge-coating a panel 2 with a coating medium B. The panel 2 is conveyed in a conveying direction during coating (see FIG. 3). The conveying direction and speed can be adapted according to a speed of the medium stream of the coating medium B.

[0054] The coating device 1 according to the exemplary embodiment comprises: two medium lines 3, each configured to guide the coating medium B, and each provided with an inlet 3a and an outlet 3b. Inlet 3a and outlet 3b are connected to a coating medium circuit of a coating system 100 (see FIG. 3). The coating medium B flows through each of the medium lines 3 in a medium flow direction M. The medium lines 3 can be connected to the coating medium circuit individually or together, for example via a Y-shaped connecting piece. The coating device 1 can have an overall width of 20 mm, for example. The line diameter in the area of the outlet 3b or the outlet piece 3B can be 19 mm at the medium lines 3.

[0055] Each of the medium lines 3 has a recess 3c for introducing the panel 2 into a coating medium stream. According to the exemplary embodiment, one edge of the panel 2 is introduced into the coating medium stream of the coating medium B. The coating medium B flows past the edge of the panel 2 and wets a surface of the panel 2 in the region of this edge.

[0056] The medium line 3 and the recess 3c are configured such that the coating medium B can be applied onto the edge 2a of the panel 2 by means of a suction in the medium flow direction M. The edge 2a comprises the edge described above. In particular, an edge profile of the recess 3c is configured to be adapted in a form-fitting manner to the edge 2a of the panel 2. In FIG. 1, it can be seen that the edge profile of the recess is configured as a counter profile to a profile of the edge 2a of the panel 2. The aforementioned suction in the medium flow direction M advantageously enables a uniform medium flow and a bubble-free conveying and coating of the panel 2.

[0057] The medium line 3 and the recess 3c are designed in such a way that a medium pressure acting as suction is generated at the recess 3c in a range from 3.5×10.sup.3 Pa to 5.5×10.sup.3 Pa for the coating medium B at the edge 2a of the panel 2. A medium pressure of 5×10.sup.3 Pa is particularly preferred. In this case, an aspect ratio of the recess 2a and of a cross-section of the medium line and the constructional design of the medium line 3 contribute to the desired medium pressure.

[0058] For this purpose, it is preferred that the coating medium B is conveyed into the inlet 3a of the coating device 1 with an inlet pressure of 10.sup.4 Pa to 2×10.sup.4 Pa. Such a low supply pressure reduces the risk that the coating medium B unintentionally reaches the panel 2 to be coated by suction in a coating manner. Nevertheless, this advantageous supply pressure is sufficient to allow the coating medium B to be conveyed through the coating device 1 by means of suction in such a way that a panel 2 can be coated in the desired manner.

[0059] The recess 3c is arranged at an outer bend of a bent medium line section. The bent medium line section has an acute inner angle (alpha), wherein the inner angle (alpha) is enclosed by an outlet piece 3B and an inlet piece 3A. The inlet piece 3A, which extends from the inlet 3a to the recess 3c, extends vertically in the state in which the medium pipe 3 is connected via the inlet 3a. The inlet 3a is then connected to the coating system 100 of FIG. 3. The medium line 3 according to the exemplary embodiment is configured U-shaped with two legs, wherein the inlet piece 3A is a first leg and the outlet piece 3B extending in the medium flow direction M from the recess 3c to the inlet 3b is a second leg.

[0060] FIG. 2 shows another schematic view of the coating device 1 according to the preferred exemplary embodiment of the disclosure. Here, the two medium lines 3 can be viewed from a different perspective.

[0061] FIG. 3 shows a schematic view of a coating system 100 according to a preferred exemplary embodiment of the disclosure.

[0062] The coating system 100 comprises: a medium line system 30 for guiding the coating medium B; a pump system connected to the medium line system 30 for conveying the coating medium B; and a coating device 1 connected to the medium line system 30 as previously described. The medium line system 30 includes a plurality of valves 80. Moreover, a coating medium container 90 filled with the coating medium B is part of the medium line system 30.

[0063] The pump system comprises a vacuum device 40 downstream of the outlet in the medium flow direction M, wherein the vacuum device 40 and a medium line cross-section of the medium line system 30 are configured to generate a negative pressure at the outlet 3b, i.e. to generate the suction behind the recess 3c.

[0064] A separator system 50 is interconnected in the medium flow direction M between the vacuum device 40 and the outlet 3b. The separator system 50 is configured to separate gas supplied to the vacuum device 40 from the coating medium B. The separator system 50 comprises a screen system 51 for separatively filtering the coating medium B from the gas. The separator system 50 further comprises a lid 52 made of acrylic glass, which is part of a housing 53 of the separator system 50. The lid 52 can be opened in order to clean the separator system 50 or to view a production process in the separator system 50. Further, the separator system 50 comprises a guide wall 54 configured to guide the gas-coating medium mixture to the screen system 51.

[0065] In the medium flow direction M between the separator system 50 and the inlet 3a a pump 60 of the pump system is interconnected, which is configured exem-plarily as an shear force-free pump 60, wherein the shear force-free pump 60 is configured for meterable conveyance of the coating medium B to the inlet 3a. The shear force-free pump 60 is a peristaltic pump, wherein the peristaltic pump comprises a hose comprising chlorosulfonated polyethylene (CSM). In principle, other pumps are also possible.

[0066] The shear force-free pump 60 and a medium line cross-section of the medium line system 30 are configured to convey the coating medium B such that the inlet 3a is supplied with the coating medium B with an inlet pressure greater than/equal to the medium pressure at the recess 3c, for example with an inlet pressure greater than 10.sup.4 Pa.

[0067] A heater 70 is interconnected in the medium flow direction M between the separator system 50, i.e. between the shear force-free pump 60, and the inlet 3a. The heater 70 is configured to heat the coating medium B to a temperature in a range from 30° C. to 45° C.

[0068] FIG. 4 shows a schematic view of a coating system according to the prior art. The coating system comprises in its medium line system a medium container 1400, which feeds the circuit with the medium for coating a panel 2. A plurality of valves 1700 are provided as part of the medium line system, wherein valves having particular functions are described in more detail below. In the coating system according to the prior art, the medium is supplied from a base machine 1100 by use of a vacuum device 1200 configured as a double diaphragm pump through a filter designed as a medium filter 1300. Subsequently, the medium is pumped by means of a pump 1500 into a pressure vessel, which is a pulsation damper 1600. The medium is then conveyed by the pressure of the pressure vessel to a coating head 1000 for coating. In this case, the line for conveying the medium must first be vented. Subsequently, the medium is pressed via a ball valve 1800, which is configured as a metering valve, at a constant pressure against the nozzle at the coating head 1000. Subsequently, the medium must be sucked off with a constant negative pressure applied to the coating head 1000. In this way, a medium flow is created at the nozzle of the coating head 1000. The coating system is then operated in a stationary state. Here, the medium is pumped in the circuit of the coating system. Here the base machine 1100 separates the medium for coating the panel 2 and a gas kept at negative pressure, which is required for coating and for the cycle. If now a panel 2 passes the coating head 1000, in a coating area of the coating head 1000, i.e., the nozzle, the vacuum can no longer suck off the medium and the panel 2 is coated, i.e., lacquered. The excess medium is sucked off and is returned into the circuit. Here, the quantity regulation is effected manually and is adjustable in a complicated way. The medium pressure in the coating head 1000 is between 15×10.sup.4 Pa and 20×10.sup.4 Pa in order to ensure that the panel 2 is sprayed or coated with the coating medium without interruption. Depending on foam formation due to spraying, an uneven coating is applied to the panel 2.

[0069] FIG. 5 shows a flow chart of an exemplary coating method.

[0070] According to a method step with the reference number “S100”, an edge 2a of the panel 2 is introduced into a coating medium stream via a recess 3c of the coating device 1.

[0071] According to a method step with the reference number “S200”, the coating medium B is conveyed in the medium flow direction M to the inlet 3a of the coating device 1 by means of a shear force-free pump 60 arranged upstream of an inlet of the coating device 1. In this case, the medium is pumped out of the separator system 50 by means of a peristaltic pump and is pumped to the coating device 1 through the heater 70, which is configured as a continuous flow heater. In this case, the coating medium B is pumped almost without pressure to the inlet 3a of the coating device 1.

[0072] According to a method step with the reference number “S300”, the coating medium B is conveyed in the medium flow direction M within the coating device 1 by means of a vacuum device 40 arranged downstream of an outlet of the coating device 1. In other words, the coating medium B is sucked through the coating device 1 to the separator system 50 while being subjected to a negative pressure.

[0073] Subsequently, according to a step with the reference number “S400”, the separator system 50 separates the coating medium B from a gas subjected to a negative pressure. The medium can be gently filtered by the screen system configured as a screen basket, and the medium can be conveyed in the circuit of the coating system 100.

[0074] During operation of the coating system 100, an air-medium mixture is generated at the recess 3c of the coating device 1, which is designed with a counter profile to the coating area of the panel 2. If now a panel 2 is moved past the coating device 1—irrespective of a travel direction—the panel 2 is coated in its coating area by the incoming flow of the air-medium mixture, i.e. lacquered. The excess medium is sucked off and returns into the circuit of the coating system 100. Here, the quantity regulation of the coating medium is fully automated.

[0075] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchange-able and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are to be re-garded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.