DE29708003U1 - Pressing / heating plate for hydraulic short-cycle and coating presses - Google Patents

Description

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Djpl.-lng. FH Anton Hartdegen, patent engineer, D-82205 Gilching

DP 1179 G, Machine factory
J. Dieffenbacher GmbH & Co.
PO Box 162

D-75020 EPPINGEN

Press/heating plate for hydraulic short-cycle and coating presses

The invention relates to a press/heating plate for hydraulic short-cycle and coating presses according to the preamble of claim 1.

When coating flat wood or other material panels with pre-glued foils, the most even distribution possible over the product in terms of both temperature and pressure is crucial for quality. In the processes and coating presses known to date, the necessary pressure is generated using rigid pressing plates and the necessary heat energy is transferred via channel holes with heat transfer media in the pressing plate.

The disadvantage of the previous process lies in the rigid press plate, which due to product tolerances and thermal deformations only allows a limited isobaric pressure distribution on the product, as well as in the channel drilling system, which only allows a limited uniform temperature distribution due to heat transfer differences under or between the channel drillings.

In a known hot plate press according to DE-AS 25 46 944, standard press plates with channel holes are used to pass the heat transfer medium through. The press plates are pressed onto the material being pressed using flexible expansion bodies that can be subjected to media pressure. This does not eliminate the disadvantage of a rigid press plate. In addition, a coating press equipped with such press plates and expansion bodies is very expensive to set up and maintain.

The invention is based on the object of creating a press/heating plate for hydraulic presses of the type mentioned, which ensures sufficient contact pressure on the coating layers at all points, even if the plane parallelism of the carrier plate to be coated deviates.

The advantages of the invention lie in the quasi-isobaric transfer of the pressing pressure and the evenly distributed temperature profile across the pressing membrane. These advantages also mean that the overall pressing force of the press can be reduced, since no more power reserves are required to bridge plate tolerances or pressing/heating plate bends.

The invention is described in more detail with reference to the drawing, three exemplary embodiments and other expedient embodiments.

Show it:

Figure 1 shows a schematic side view of a short-cycle press without a press frame with the press/heating plate according to the invention,

• it

Figure 2 shows a detail from Figure 1 of a second embodiment of the

movable upper pressing/heating plate and Figure 3 shows a detail from Figure 1 of a third embodiment of the movable upper pressing/heating plate.

Figure 1 shows a schematic representation of the press/heating plate 8 or 8' according to the invention in a short-cycle press in side view and the press pressure cylinders 6 responsible for the up and down movement of the upper press/heating plate 8, which are supported in a press frame (not shown). The press/heating plates 8, 8', the lower fixed press/heating plate 8' is constructed in a mirror image to the upper press/heating plate 8, each consist of a stable base plate 1, 1', the channels 3, 3' cut into the base plate 1, 1' and thin, easily deformable pressure plates 2, 2', which are connected to the base plates 1, 1' in a pressure-tight manner and serve as a membrane for the quasi-isobaric press pressure transfer to the material to be pressed 9. The heat transfer medium is initially pumped through the channels 3, 3' without pressure. If the pressure cylinders 6 reach a minimum pressure on the material to be pressed 9, the heat transfer medium is subjected to the necessary pressure via a temperature-insulated reverse pressure amplifier and thereby separates the pressure plates 2, 2' from the base plate 1, 1' in a quasi isobaric manner.

According to a second embodiment in Figure 2, the heat transfer medium can also be supported by a flexible pipe system consisting of pressure hoses 4,4' against the base plates 1,1' and the quasi isobaric pressing pressure can be applied to the pressure plate 2, 2' or to the material to be pressed 9

The flexible pressure hoses 4, 4' are accommodated in the channels 3, 3' of the base plates 1, 1' at a distance X from the webs 7, T (or their thickness). The pressure plates 2, 2' must be made thicker the greater the thickness X of the webs 7, T. However, if the thickness X of the webs 7, T approaches zero according to the third embodiment shown in Figure 3, these pressure plates 2, 2' can be made extremely thin so that the pressure distribution approaches an absolute isobaric pressure distribution.

According to a third embodiment in Figure 3, the upper and/or lower pressing/heating plate (8, 8') each consists of a stable base plate (1, ¹¹ ) with a pressure chamber (10) recessed towards the pressing surface (5) and of a thin, deformable pressure plate (2, 2') covering this pressure chamber in a pressure-tight manner, wherein a serpentine, flexible pipe system made up of pressure hoses (4, 4') is arranged in the pressure chamber (10) in such a way that a pressurized heat transfer medium can be passed through, which serves for the uniform transfer of the heat quantity and for the quasi-isobaric pressure transfer to the pressure plate (2, 2').

In contrast to the use of a membrane (bladder) according to the state of the art, the pressure hoses 4, 4' can be better dimensioned to protect against excess pressure, grouped into individual zones and subjected to different pressures, in order to then be able to cover only part of the pressing surface with smaller formats. When coating smaller formats of layered pressed material 9, overloads would otherwise occur on the

Transitions of the pressing/heating plate 8, 8' from existing to non-existent material to be pressed, since there are no opposing forces to counteract the pressure of the pressing/heating plate 8, 8'. Different coating materials, which require different pressures and temperatures, can also be advantageously applied to the carrier plate and pressed.

In order to avoid an unnecessarily strong heating of the base plate 1, 1', the recessed areas of the channels 3, 3' or the pressure chambers 10 facing the pressing surface 5 are expediently provided with suitable insulation 11.

Another useful design of the press/heating plate 8, 8' is that the channels 3, 3' or the pressure hoses 4, 4' are combined in sections with one or more channels 3, 3' or pressure hoses 4, 4' running across the width of the press surface 5, along the side of the press and can thus be subjected to zones of different pressure and/or temperature. This means that overloading of the press/heating plate 8, 8' can be avoided if only short pressed material 9, which does not require the full length of the press (or the press surface), is to be coated. Furthermore, this could compensate for scattering or coating errors with the risk of damage to the press.

The press/heating plate 8, 8' according to the invention can be used with advantages for both single- and multi-stage presses.

List of reference symbols

DP1179

1.1'. Base plate

2. 2'. Printing plate

3. 3'. Channels

4. 4'. Pressure hose

5. 5'. Pressing surface

6. Press pressure cylinder

7. T bars

8. 8' Press/Heating Plate

9. Pressed material

10. Printing room

11. Insulation

Strength of 7, T

Claims (6)

Dipl.-Ing. FH Anton Hartdegen, Patent Engineer, D-82205 Gilching DP 1179 Maschinenfabrik J. Dieffenbacher GmbH & Co. Postfach 162 D-75020 EPPINGEN Protection claims 1. Press/heating plate for hydraulic short-cycle and coating presses for producing layered pressed material, which consists of flat carrier plates with top and/or bottom coating layers made of hardenable synthetic resin or hardenable synthetic resin films, veneers, papers, etc. for laminating and gluing wood-based panels, characterized in that the upper and/or lower press/heating plate (8, 8') each consists of a stable base plate (1, V) with a channel system (3, 3') recessed towards the pressing surface (5) and of a thin, deformable pressure plate (2, 2') covering this channel system (3, 3') in a pressure-tight manner, the channel system (3, 3') being designed in such a way that a pressurized heat transfer medium can be passed through, which serves for the uniform transfer of the heat energy and for the quasi-isobaric pressure transfer to the pressure plate (2, 2') . 2. Press/heating plate for hydraulic short-cycle and coating presses for the production of layered pressed material, which consists of flat carrier plates with top and/or bottom coating layers made of hardenable synthetic resin or hardenable synthetic resin films, veneers, papers • it·« ·· · _&bgr; · J etc. for laminating and gluing wood-based panels, in particular according to claim 1, characterized in that the upper and/or lower pressing/heating plate (8, 8') each consists of a stable base plate (1, V) with channels (3, 3 ¹ ) cut out towards the pressing surface (5) and of a thin, deformable pressure plate (2, 2') covering these channels (3, 3') in a pressure-tight manner, wherein a flexible pipe system made of pressure hoses is arranged in the channels (3, 3') in such a way that a pressurized heat transfer medium can be passed through, which serves for the uniform transfer of the heat energy and for the quasi-isobaric pressure transfer to the pressure plate (2, 2'). 3. Press/heating plate for hydraulic short-cycle and coating presses for the production of layered pressed material, which consists of flat carrier plates with top and/or bottom coating layers made of hardenable synthetic resin or hardenable synthetic resin films, veneers, papers, etc. for laminating and gluing wood-based panels, in particular according to claim 1, characterized in that the upper and/or lower pressing/heating plate (8, 8') each consists of a stable base plate (1, V) with a pressure chamber (10) recessed towards the pressing surface (5) and of a thin, deformable pressure plate (2, 2') covering this pressure chamber in a pressure-tight manner, wherein a serpentine, flexible pipe system made of pressure hoses (4, 4') is arranged in the pressure chamber (10) in such a way that a pressurized heat transfer medium can be passed through, which serves to evenly transfer the amount of heat and to quasi-isobarically transfer pressure to the pressure plate (2, 2'). 4. Press/heating plate according to claims 1 to 3, characterized in that the channels (3, 3') or the pressure hoses (4, 4') within the base plate (1, 1") are each combined to form zones of different pressing pressure and/or heat and can be acted upon. 5. Press/heating plate according to claim 1 or 2, characterized in that the channels (3, 3') are separated by webs (7, 7') whose thickness (X) is designed according to Roetscher's pressure distribution cone of 45°, that is, the larger the dimension X, the greater the thickness of the pressure plates (2, 2') 6. Press/heating plate according to claims 1 to 4, characterized in that the recessed surfaces of the channels (3, 3') or the pressure chamber (10) of the base plate (1, 1') facing the pressing surface (5) have insulation (11) to prevent unnecessary heat transfer.