FI68785B - YTBEKLAEDNINGSFOERFARANDE OCH ANORDNING - Google Patents

Description

68785 ι

Coating method and apparatus - Ytbeklädninsförfarande och anordning

The invention relates to a coating method for applying a coating plate or film mainly to one or both sides of a plate-like body using adhesive and vacuum compression between two surfaces to be arranged outside them, which method uses surfaces made of airtight material and hermetically connected at their edges.

The gluing of a veneer or laminate surface to the main surfaces of chipboard pieces is generally carried out in industrial production by pressing the surfaces to be joined together between which the adhesive is applied between two rigid, usually heated, planar surfaces, usually in a hydraulic press. Compression is continued until the adhesive has set.

The disadvantage of such a method is the high cost of the equipment required, in which case small carpentry shops usually have to subcontract the work in question or use, for example, contact glue and slow handicraft methods.

On the other hand, the compression between two rigid planar surfaces also brings with it some technical problems. For example, variations in the thickness of the sheet to be coated or, correspondingly, irregularities in the compression levels cause the coating sheet not to adhere to the sheet to be coated at every point. Also, in some cases, bending of the plates may occur due to the different rate of heat evaporation of the upper and lower surfaces when the compression takes place between the planar surfaces to be heated.

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When the coating sheet is a highly glossy laminate, the above method does not achieve a completely satisfactory result because the compression is never completely uniform at every point on the surface, and thus an unevenness remains on the surface, which is easy to detect on the glossy surface.

The method according to the invention provides a decisive improvement in the above-mentioned drawbacks. To achieve this, the method according to the invention is characterized in that at least one of the compression-transmitting surfaces is made of a flexible material, preferably rubber.

The most important advantage of the invention is that the necessary equipment is inexpensive and very simple in structure compared to the past. In addition, the method according to the invention achieves a completely flawless result more reliably than before.

In the following, the invention will be explained in detail with reference to the accompanying drawing.

Figure 1 shows a cross-section of a device according to the invention. Two plates to be coated simultaneously.

Figure 2 shows a cross-section of a device according to the invention.

To be coated, the other main surface of the board and two opposite, rounded edges.

Figure 3 shows an embodiment of the device according to the invention, in which the rim is made compressible.

Fig. 1 schematically shows a cross-section of a device according to the invention, where the number 1 denotes a rectangular base plane of the device, which is supported (not shown 3 68785) so that the coating plates 2, 3 on it cannot bend under its own weight. The lid of the device is formed, for example, by a rim 4 made of steel rectangular tube and a rubber film 5 hermetically connected to it. There is a seal 6 between the rim 4 and the base plane 1. Air is sucked out of the airtight space 7 thus formed through the tube 8.

In the application example of Fig. 1, there are two plates 2 and 3 to be coated on both sides with the coating plates 9-12 and on top of these a support plate 13, the purpose of which is only to prevent the uppermost coating plate 12 from folding from its edge. Of course, edge folding can be prevented in many other ways.

Figure 2 shows the coating of an edge-curved plate 14 with a coating plate 15 with the plate 16 preventing the edge of the coating from bending.

There is an air gap between the top plate and the rubber film 5 when the system is at rest, which decreases as the pressure is reduced and finally said surfaces contact each other. The contact begins in the middle of the rubber film 5 and continues as a flat front to the edges of the plate as a vacuum is applied, allowing any air or excess adhesive between the surfaces to be glued to escape, avoiding air bags, wrinkles, etc. This is all the more important the thinner the film.

In the embodiment of the invention shown in Figure 3, the steel rectangular tube rim 4 shown in Figures 1 and 2 has been replaced by a suitably stiffened rubber hose rim 20, the interior 21 of which is connected via a tube 22 to a non-shown 4 68785 pressure control valve the control valve is designed in such a way that, if necessary, it also takes into account the pressure prevailing in the space 7.

The compressible rim 20 shown in Fig. 3 is used in such a way that after the lid 5 has been compressed in the middle due to the lower pressure in the space 7, air is also slowly sucked from the interior 21 of the rim 20, whereby the rim 20 is compressed. By means of the pressure control valve, the compression of the rim 20 is arranged to take place synchronously with the emptying of the space 7. Thus, pieces with edges above the center can also be coated.

In particular, it should be noted that the device according to the invention can also be applied to coating curved surfaces with a laminate sheet when a heating mat is placed between it and the rubber film 5, the purpose of which is to heat the brittle laminate to a flexible temperature. In complex bending, the laminate can be pre-bent in advance, in which case only the actual fixing takes place in the device according to the invention.

The invention has been described above only with reference to some preferred embodiments thereof. However, this is in no way intended to limit the invention to these examples only, but many modifications are possible within the scope of the inventive idea defined by the following claims.

Claims (4)

1. Surface coating method for attaching a cladding disc or film (9-12, 15) to one or both sides of an almost disc-shaped piece (2, 3, 14) using glue and a surface outside (2, 5) by vacuum Sustainable pressure, in which the method is used of airtight material made and with its edges airtightly interconnected surfaces (1, 5), the air being removed from the well-formed space (7), as indicated therein, that at least one of the pressure mediating surfaces (1, 5) is made of elastic material, most preferably rubber. Apparatus for attaching to one or both sides of an almost disc-shaped piece (2, 3, 14) a cladding disc or film (9-12, 15) using glue and a surface disposed between two of these (1, 5) by vacuum obtainable pressure, to which the device belongs to airtight material made and with its edges airtightly connected to each other (1, 5), the space thus formed (7) being connected to the vacuum attaching devices, characterized therein; that at least one of the pressure mediating surfaces (1, 5) is made of elastic material, most preferably rubber.