EP1533110B1 - Hot pressing apparatus with a press plate and at least an elastic layer - Google Patents

Description

The invention relates to a pressing device with a press plate for hot pressing of pressed material from the group laminates, wood materials, wood-plastic materials, chipboard, wood-paper, foil and Pappkombinationen for floors, walls and ceilings, wherein the pressing device at least one heatable press plate and wherein between the pressure plate and the press plate at least one elastic coating is arranged.

In such heated pressing devices, which may be parts of a single or platen press, it is to achieve short cycle times and uniform pressing effects in order to ensure the highest possible and uniform heat transfer and extremely uniform distribution of high compressive forces over the entire pressed material. It must be remembered that it can be pressed material dimensions of 6 m x 9 m and above.

Negative examples of poor heat transfer are - but there wanted - multiple glazing of windows and evacuated thermos.

In the field to which the state of the art and the invention belong, the experts distinguish between press pads and coated press plates.

Press pad:

By the DE 26 27 442 A1 a press pad for hot plate presses is known in which a fabric of a random fiber nonwoven fabric is coated on both sides with silicone rubber.

By the EP 0 920 982 A1 For example, a press pad is known from a fabric of intersecting filaments, the core of which is, for example, a silicone elastomer thread having a Shore A hardness of 60 to 75 wrapped by at least one metal wire. The metal wires can be connected as electrical heating resistors. Air pockets between the tissue and the pressed material are thereby not excluded.

By the EP 1 040 909 A1 It is known to provide an inherently elastic press pad on both sides with outer layers which are interconnected by a plurality of spacer threads. To improve the heat transfer should be at least a portion of the spacer threads made of metal wires. However, these can not compensate for the insulating effect of the enclosed air cushion by far.

By the DE 200 11 432.U1 It is known in a press pad to embed a textile fabric of polyamide and metal threads at least on one side in a continuous layer of a heat-resistant and pressure-resistant polymer material.

By the DE 100 34 374 A1 It is also known, for producing a thermally conductive press pad with a maximum thickness of 2.2 mm and without trapping air to coat a metal fabric from the top on both sides with a metal powder-containing silicone composition with a crosslinker and cure this press pad.

By the DE 200 13 422 U1 is a press pad of intersecting threads or filament bundles known, of which at least a part has magnetic properties for fixing to a heating plate. There is no question of removing insulating air pockets.

By the DE 201 15 945 U1 is a press pad known in which heat conduction partially embedded in a mass of rubber-elastic material and protrude from both outer sides of the press pad. Since the air masses between the projecting metal wires and the thermal conductivity of the metal filaments are diametrically opposed to each other. Even if the metal filaments are incorporated into the elastic material during the very limited operating time, another problem arises, namely the lack of possibility that air trapped between the press pad and the pressure plate can escape.

In order for the pressing device to be opened, such short-lived press cushions must be hung on the upper press plate so that they "hang down" in the manner of hammocks in the middle, if they do not contain just magnetic material - such as the subject of DE 200 13 422 U1 - And also the pressure plate consists of a magnetic material such as steel. However, this in turn increases the problem that air pockets between the press pads and the press plate can not or only slowly escape, and this problem increases with increasing smoothness of the surface facing the press plate. In other words, here too, the necessary thermal contact and the air inclusions are diametrically opposed.

Coated press plates:

As press plates, the pure metal sheets or metal plates are referred to in practice, which can be referred to as a support plates as a result, because they have a supporting function for applied coatings and coatings of one or more components in practice.

By the DE 39 11 958 A1 is a press plate for cold pressing of mineral materials is known in which at least one outer layer of an ultra-high molecular weight thermoplastic material such as polyethylene is applied to a light metal panel as press plate. Such a surface is hard. In this case, however, the heat transfer during pressing of the pressed material is irrelevant, and the elasticity to compensate for inhomogeneities in the surface of the pressed material also plays no role.

By the DE 40 05 157 C1 a press plate for hot pressing of pressed material is known, wherein a corrosion-resistant and scratch-resistant glass coating is applied to the press plate for the production of highly smooth surfaces on the pressed material, which is also not elastic in itself. Again, the elasticity to compensate for inhomogeneities in the surface of the pressed material does not matter.

By the DE 42 09 670 C1 Press plates are known for a hot press for pressed material (decorative laminate with a textured surface) with a maximum thickness of 1.2 mm, wherein between the press plates and the pressure plates padding layers are arranged. However, no information is given about their properties, in particular about which materials the upholstery layers consist of and whether they are free of air inclusions. It is about the solution of another object, namely the shielding of surface areas not used in the pressing process smaller pressing material by removable protective masks against damage and contamination.

From the DE 33 25 574 A1 a plate press for the production of wood-based panels is known which comprises an upper press plate and a structural plate arranged thereunder, between which a press pad is arranged, and wherein the structural sheet is held by vacuum on an elastically deformable support plate. The support plate is attached at the open plate press together with the structural sheet hanging on the upper press plate. Due to the sagging structural plate, a rapid closing of the plate press is to be made possible because the air cushion between the upper structural plate and the pressed material pressed out easily when closing the plate press from the slits formed as a result of slack becomes. In the known plate press, the advantages in closing and opening the plate press can be achieved even if the press pad is missing. But then air bubbles can not be avoided.

From the CH 509 877 A inter alia, a device according to the preamble of claim 1 is disclosed.

The invention is based on the object of specifying a coated press plate of the type described above for hot pressing, with the short cycle times and uniform or full-surface pressing effects for the highest possible and uniform heat transfer by avoiding air inclusions and Kältenestern and an extremely uniform distribution of high pressing forces over the entire Pressing material, long service lives and a low product scrap are achieved, especially for pressed material dimensions up to 6 mx 9 m and above.

The solution of the problem is solved according to the invention by the features mentioned in the characterizing part of claim 1.

With these features, short cycle times and uniform or full-surface pressing effects for the highest possible and uniform heat transfer by avoiding air inclusions and Kältenestern and an extremely uniform distribution of high compressive forces over the entire pressed material, long service life and low product scrap achieved. This applies in particular to pressed material dimensions of up to 6 m x 9 m and above. An increase of the usual working temperature of the pressure plate of example approx. 200 ° C can be avoided by avoiding air inclusions, whereby unnecessary heat losses are avoided.

• * der elastische Belag eine Shore-A-Härte zwischen 40 und 80, insbesondere zwischen 50 und 70 und vorzugsweise von etwa 60 aufweist,
• * der elastische Belag aus einem Silikonwerkstoff besteht,
• * der elastische Belag mit partikelförmigen Metalleinlagen versehen ist,
• * der elastische Belag mittels eines Haftvermittlers mit dem Pressblech verbunden ist,
• * der elastische Belag eine Dicke von 1 bis 4 mm aufweist,
  der elastische Belag in Zonen unterschiedliche Shore-A-Härten unterteilt ist,
• * der elastische Belag an den Randzonen des Pressblechs die jeweils relativ grösste Shore-A-Härte aufweist,
• * das Pressblech eine Dicke zwischen 2 und 8 mm, vorzugsweise zwischen 3 und 5 mm aufweist,
• * das Pressblech aus mindestens einem Metall aus der Gruppe Edelstahl, Kupfer und Messing besteht,
• * der elastische Belag des Pressblechs auf der der Pressplatte zugekehrten Seite mit einer Schicht aus einem weichen Metall versehen ist,
• * die metallische Schicht aus Kupferblech besteht und eine Dicke zwischen 0,3 und 0,4 mm aufweist,
• * die metallische Schicht aus einem feinen, in den elastischen Belag eingebetteten Metallgewebe besteht,
• * das Pressblech auf der der Pressplatte zugekehrten Seite eine alternierende Schichtenfolge aus mindestens zwei elastischen Schichten und mindestens zwei Schichten aus weichem Metall aus der Gruppe der Metallfolien und der Metallgewebe aufweist,
• * der Gesamtaufbau des beschichteten Pressblechs und der Pressplatte frei von Lufteinschlüssen ist,
• * der Gesamtaufbau des beschichteten Pressblechs zumindest weitgehend selbsttragend ausgebildet ist,
• * der Gesamtaufbau des beschichteten Pressblechs mit mindestens einer das Pressblech durchdringenden Schraube an der Unterseite der Pressplatte befestigt ist, und/oder, wenn
• * der Gesamtaufbau des beschichteten Pressblechs am Umfangsrand der Pressplatte befestigt ist.

It is particularly advantageous in the course of further embodiments of the invention, if - either individually or in combination -:

• the elastic covering has a Shore A hardness between 40 and 80, in particular between 50 and 70 and preferably of about 60,
• * the elastic lining consists of a silicone material,
• * the elastic covering is provided with particulate metal inserts,
• * the elastic covering is connected by means of a bonding agent to the press plate,
• * the elastic covering has a thickness of 1 to 4 mm,
  the elastic covering is divided into zones of different Shore A hardnesses,
• * the elastic coating on the edge zones of the press plate has the relatively largest Shore A hardness,
• * the press plate has a thickness between 2 and 8 mm, preferably between 3 and 5 mm,
• * the press plate consists of at least one metal from the group stainless steel, copper and brass,
• the elastic covering of the press plate is provided with a layer of soft metal on the side facing the press plate,
• the metallic layer consists of copper sheet and has a thickness between 0.3 and 0.4 mm,
• the metallic layer consists of a fine metal fabric embedded in the elastic covering,
• * the press plate on the side facing the press plate has an alternating layer sequence of at least two elastic layers and at least two layers of soft metal from the group of metal foils and the metal fabric,
• * the overall structure of the coated press plate and the press plate is free of trapped air,
• * the overall structure of the coated press plate is at least largely self-supporting,
• * the overall structure of the coated press plate is secured to the underside of the press plate with at least one screw penetrating the press plate and / or, if so
• * The overall structure of the coated press plate is attached to the peripheral edge of the press plate.

The application of the elastic coating can be done either by uniform brushing, extruding from a slot or by pouring a first easily flowable mass of one or more nozzles according to a predetermined, very narrow and uniform distribution pattern on the press plate, wherein the first flowable mass at least largely distributed by itself, and then let the mass stand up to reach the predetermined Shore A hardness, for which silicone resins are particularly well suited.

Embodiments of the subject invention and their modes of action are described below with reference to the FIGS. 1 to 7 explained in more detail, which are highly schematic and not necessarily true to scale.

Figur 1

einen Vertikalschnitt durch die wesentlichen Teile einer Pressvorrichtung mit Pressgut, Pressblech und elastischem Belag,

Figur 2

einen Vertikalschnitt durch ein Pressblech mit einem einzigen elastischen Belag,

Figur 3

einen Vertikalschnitt durch ein Pressblech mit einem elastischen Belag, der Zonen oder Bereiche unterschiedlicher Shore-AHärte, aufweist,

Figur 4

den Gegenstand von Figur 3 mit einer zusätzlichen Schicht aus Metall,

Figur 5

in einer Draufsicht eine Ecke eines Pressblech mit einem elastischen Belag nach Figur 2, auf den eine Schicht aus einer weichen Metallfolie aufgebracht ist, die zur besseren Übersicht zum Teil entfernt ist,

Figur 6

eine Ecke eines Pressblechs nach Figur 3 in der Draufsicht und

Figur 7

einen Vertikalschnitt durch ein Pressblech mit einem Belag, der sich alternierend aus elastischen und weichen metallischen Schichten zusammensetzt.

Show it:

FIG. 1

a vertical section through the essential parts of a pressing device with pressed material, press plate and elastic lining,

FIG. 2

a vertical section through a press plate with a single elastic coating,

FIG. 3

a vertical section through a press plate with an elastic coating, the zones or areas of different Shore A hardness has,

FIG. 4

the object of FIG. 3 with an additional layer of metal,

FIG. 5

in a plan view, a corner of a press plate with an elastic coating after FIG. 2 on which a layer of a soft metal foil is applied, which is partially removed for clarity,

FIG. 6

a corner of a press plate behind FIG. 3 in plan view and

FIG. 7

a vertical section through a press plate with a covering, which is composed of alternating elastic and soft metallic layers.

In FIG. 1 2 shows a section of a press device 1, which denotes a machine lower part 2, also referred to as a machine table, and a press plate 3, also referred to as a machine upper part, which is movable in the vertical direction by a plurality of synchronously acting drive elements 4, wherein the drive elements are used as hydraulic actuators. or pneumatic cylinders, but can also be designed as mechanical drive elements such as spindle drives. The usual, these components surrounding press frame is not shown for simplicity. Since it is a device for hot pressing of pressed material 5, machine base 2 and press plate 3 are provided with heaters. These press components and their functions are known and are therefore not described in detail.

By pressing device 1, the pressed material 5 solidifies in itself, be provided with a flat decorative coating and / or a surface profiling such as a wood pattern.

On the press plate 3, a press plate 6 is suspended from metal, by vertical bends 6a with vertical slots 7 and horizontal screws 8 at the peripheral edge 3a of the press plate 3 and / or by vertical, preferably only in the edge region arranged countersunk screws 9, not from the Press plate 6 protrude below. Decisive in this case is the intermediate layer of an inherently elastic covering 10 which is either single-layered or multi-layered in the vertical direction can be, or even in the horizontal direction zones or areas of different Shore A hardness may have. This will be discussed in more detail in connection with other figures.

Preferably, as elastic coating components, those with Shore A hardnesses between 40 and 80, even better those with Shore A hardnesses between 50 and 70, in particular those with Shore A hardnesses of about 60 in question. It is according to DIN 53 505 to dimensionless units. Very suitable are silicones or silicone materials. It will be on the RöMMP CHEMIE LEXIKON, Edition 1995, page 4137 and pages 4168 to 4172 directed.

Particularly important are the completely flat design of the press plate 6, the covering 10, the prevention of air inclusions, both within the lining 10 and between this covering 10 and the pressing plate 3 on the one hand and the pressed material 5 on the other. On the one hand, the elasticity of the lining 10 must be sufficiently high, on the other hand, but also the thermal conductivity, which can be improved by the incorporation of particles, tissues or networks of metal.

For the thickness of the elastic covering 10 or the sum of all elastic layer components of the lining 10 is a range between 1 and 4 mm in question. For the thickness of the press plate 6, a range between 2 and 8 mm, preferably between 3 and 5 mm. The compound of the lining 10 with the press plate 6 can preferably be improved by a bonding agent. Such adhesion promoters or adhesives are known per se and are commercially available. Please refer RöMMP CHEMIE LEXIKON, 1995 Edition, pages 1703 and 1704 ,

The FIG. 2 shows a vertical section through a press plate 6 with a single, single-layer elastic coating 10. Die FIG. 3 shows a vertical section through a press plate 6 with an elastic covering 10, the zones or regions 10a and 10b of different Shore A hardness, having, preferably, the area 10a with the larger Shore A hardness above all over the entire peripheral region of the press plate 6 extends. The FIG. 4 shows the item of FIG. 3 with an additional metal layer 11, eg a soft metal foil.

The FIG. 5 shows a corner of a protruding edge 6 b pressing plate 6 with an elastic coating 10 after FIG. 2 on which a layer 11 made of a soft metal foil is applied, which is partially removed for better clarity. The FIG. 6 shows a corner of a press plate 6 after FIG. 3 in plan view with zones or regions 10a and 10b of different Shore A hardnesses. This layer design enables a compensation of different surface geometries of the pressed material 5 (FIG. FIG. 1 ). With the subject invention, it is possible to exert the same compressive forces on the pressed material 5 with each surface element of the lining at the same temperatures.

The FIG. 7 shows a vertical section through a press plate 6 with a coating 10, which is composed alternately of three elastic layers 10c and two soft metal layers 11, which consist for example of copper sheet and / or a copper fabric with a thickness of 0.3 to 0.4 mm ,

LIST OF REFERENCE NUMBERS

1

pressing device

2

Machine part

3

press plate

3a

circumferential edge

4

power Transmission

5

pressed material

6

press plate

6a

bends

6b

edge

7

slots

8th

screw

9

countersunk screws

10

elastic covering

10a

Zones or areas

10b

Zones or areas

10c

Layer, metal layer

11

layer

Claims (18)

1. Pressing apparatus having a pressure plate (6) for the hot pressing of material (5) from the group laminates, wood materials, wood-plastic materials, chip and flake board, wood, paper, film and pulpboard combinations for floor, walls and ceilings, wherein the pressing apparatus (1) has at least one heatable platen (3), and wherein an resilient lining (10) is disposed between the platen (3) and the pressure plate (6) characterized in that the pressure plate (6) has on opposite sides perpendicular upturned portions (6a) with perpendicular slots (2) via which the pressure plate (6) is suspended to the marginal edge (3a) of the pressure plate (6) by means of horizontal screws (8), the pressure plate (6) has on the side facing the platen (3) between the upturned portions (6a) at least one lining (10) of a thermally conductive, resilient plastic tightly adhering to the pressure plate (6) and that the pressure plate (6) lies with its lining (10) free of air gap against the platen (3).
2. Pressing apparatus according to claim 1, characterized in that the resilient lining (10) has a Shore-A hardness between 40 and 80.
3. Pressing apparatus according to claim 2, characterized in that the resilient lining (10) as a Shore-A hardness between 50 and 70.
4. Pressing apparatus according to claim 2, characterized in that the resilient lining (10) has a Shore-A hardness of about 60.
5. Pressing apparatus according to claim 1, characterized in that the resilient lining (10) consists of a silicone material.
6. Pressing apparatus according to claim 1, characterized in that the resilient lining (10) is provided with metal embedments in particle form.
7. Pressing apparatus according to claim 1, characterized in that the resilient lining (10) is bonded with an adhesive to the pressure plate (6).
8. Pressing apparatus according to claim 1, characterized in that the resilient lining (10) has a thickness of 1 to 4 mm.
9. Pressing apparatus according to claim 1, characterized in that the resilient lining (10) has zones (10a, 10b) of different Shore-A hardness.
10. Pressing apparatus according to claim 9, characterized in that the resilient lining (10) has the relatively greatest Shore-A hardness at the marginal zones of the pressure plate (6).
11. Pressing apparatus according to claim 1, characterized in that the pressure plate (6) has a thickness between 2 and 8 mm.
12. Pressing apparatus according to claim 11, characterized in that the pressure plate (6) has a thickness between 3 and 5 mm.
13. Pressing apparatus according to claim 1, characterized in that the pressure plate (6) consists of at least one metal from the group of stainless steel, copper and brass.
14. Pressing apparatus according to claim 1, characterized in that the resilient lining (10) of the pressure plate (6) is provided on the side facing the platen (3) with a layer (11) of a soft metal.
15. Pressing apparatus according to claim 14, characterized in that the metal layer (11) consists of sheet copper and has a thickness between 0,3 and 0,4 mm.
16. Pressing apparatus according to claim 14 characterized in that the metal layer (11) consists of a fine metal mesh embedded in the resilient lining (10).
17. Pressing apparatus according to claim 1, characterized in that the pressure plate (6) has on the side facing the platen (3) a series of layers of at least two resilient layers (10c) and at least two layers (11) of soft metal from the group of the metal foils and metals meshes.
18. Pressing apparatus according to claim 1, characterized in that the overall structure of the layered pressure plate (6) is fastened to the underside of the platen (3) with at least one screw (4) penetrating the pressure plate (6).

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