METHOD AND APPARATUS FOR MAKING INSULATING PANELS

Abstract

The invention relates to a device and a method having a first and a second zone (Z1, Z2) for producing insulating or acoustic panels from a pressed material mat (2) which consists at least partially of lignocellulose particles coated with binders, the first zone (Z1) being designed for heating and/or compressing the pressed material mat, and the second zone (Z2) being designed for curing the pressed material mat with the aid of calibration plates (3), and there being driven circulating screen bands (5a-5f) in contact with the upper and lower pressed material mat surfaces. According to the invention, to increase the production speed, at least four circulating screen bands (5a-5f) are used, at least two of which are in operative contact with the pressed material mat (2) in the region of the first zone (Z1), and at least two of which are in operative contact with the pressed material mat (2) in the region of the second zone (Z2).

Claims

1. An apparatus having an upstream and a downstream zone for making insulating or soundproofing panels from a pressed-material mat consisting at least partially of lignocellulosic particles wetted with a binder, the upstream zone being designed to heat and/or compress the pressed-material mat and the downstream zone being designed to harden the pressed-material mat with the aid of calibration plates, the apparatus comprising: at least four driven endless mesh belts operatively engaging upper and lower mat faces, at least two of the belts operatively engaging the pressed-material mat in the upstream zone and at least two others of the belts operatively engaging the pressed-material mat in the downstream zone.

2. The apparatus according to claim 1, wherein each of the at least four mesh belts has its own drive.

3. The apparatus according to claim 1, further comprising: a device for applying steam to the pressed-material mat in the upstream zone and a device for air cooling of the pressed-material mat at the end of the downstream zone.

4. The apparatus according to claim 1, further comprising: a height-adjustable intake opening.

5. The apparatus according to claim 4, further comprising: a steam device is in the intake opening.

6. The apparatus according to claim 1, wherein the calibration plates are heatable.

7. The apparatus according to claim 1, wherein the upstream and the downstream zones are directly adjacent one another.

8. The apparatus according to claim 1, further comprising: respective pluralities of deflection rollers over which the belts are spanned; and a slide shoe bridging a gap between the mesh-belt deflection rollers of a lower one of the mesh belts in the upstream zone and an adjacent deflection roller of a lower one of the mesh belts in the downstream zone.

9. A method of making insulating or soundproofing panels from a pressed-material mat consisting at least partially of lignocellulosic particles wetted with binders, the method comprising: using at least four endless mesh belts of which at least two act on the pressed-material mat in the upstream zone and of which at least two act on the pressed-material mat in the downstream zone.

10. The method according to claim 9, further comprising the step of: advancing each of the at least four mesh belts by a respective independent drive.

11. The method according to claim 9, further comprising the steps of, in the upstream zone, applying steam to the pressed-material mat and, at the end of the downstream zone, air cooling the pressed-material mat.

12. The method according to claim 9, further comprising the step of: varying a size of an intake opening at upstream ends of the belts in the upstream zone by a device according to the type of the incoming pressed-material mat to be treated.

13. The method according to claim 12, further comprising the step of: steam treating the pressed-material mat in the intake opening.

14. The method according to claim 9, wherein the upstream and the downstream zones are directly adjacent one another.

15. The method according to claim 14, further comprising the step of: guiding the pressed-material mat in a gap between two mesh-belt deflection rollers via a bridging slide shoe where the upstream and downstream zones are directly adjacent one another.

Description

[0026] In the following, the invention is described in more detail with reference to a drawing showing several embodiments. Therein:

[0027] FIG. 1 is a schematic view of a first embodiment of the invention.

[0028] FIG. 2 is a schematic view of a second embodiment of the invention;

[0029] FIG. 3 is a schematic view of a third embodiment of the invention,

[0030] FIG. 4 is a schematic detail view showing a slide shoe between zones 1 and 2.

SPECIFIC DESCRIPTION

[0031] FIG. 1 is a schematic side view of the apparatus according to the invention for making insulating panels. A pressed-material mat consisting at least partially of lignocellulosic particles wetted with a binder is treated between an upper circulating mesh belt 5a and a lower circulating mesh belt 5d in an upstream zone Z1 and a downstream zone Z2. The separation of the zones is indicated in all figures by a dot-dash vertical line.

[0032] In the past, the pressed-material mat has been heated between a single upper and a single lower mesh belt reach of the belts with steam or a steam/air mixture and is then cured by application of heat via calibration plates. Production speeds were limited by the tensile strengths of the meshes.

[0033] FIG. 1 shows however that two further endless mesh belts are within the endless upper mesh belt 5a and the endless lower mesh belt 5d. In the upper part of the apparatus, they are shown at 5b and 5c, and in the lower part of the apparatus at 5e and 5f. Each of the rotating mesh belts 5a-5f has its own drive formed by a respective driven deflection roller 8.

[0034] In the upstream part of the apparatus at an intake opening 9 the pressed-material mat 2 resists compression until softened by treatment by steamers 4a and 4b so that most of the friction that the drive has to overcome is generated there. According to the invention, this zone Z1 holds two separate rotating mesh belts each with its own drive. As a result, the tensile load on the long endless mesh belts 5a and 5d decreases. The same applies to zone Z2 where the pressed-material mat 2 is hardened. Here too, separate circulating and driven mesh belts 5c, 5f are provided above and below the pressed-material mat 2 for assisting in transport. Overall, considerably higher speeds can be achieved with this arrangement.

[0035] The devices 4a and 4b for applying steam are provided in zone 1, that is to say within the endless mesh belts 5b and 5e. Thus steam penetrates through the rotating mesh belts 5a and 5b or 5d and 5e into the pressed-material mat 2 and condenses. Residual steam and residual air emerging can be aspirated and discharged by suction devices 6a and 6b.

[0036] A further device for applying steam 4c can be provided, for example, at the intake opening 9. The moist face produced thus reduces friction on the mesh belts 5a and 5d, which leads to additional energy savings.

[0037] High-efficiency calibration plates 3, which can be heated via different systems, are provided in zone 2. For example, passages traversed by heating fluid, inductive heaters, electric heating are used here or steam heaters, the latter also being able to deliver the steam directly to the mat of pressed material even in the hardening zone.

[0038] At the outlet of the apparatus, the pressed-material mat is cooled by a suction device 6c that pulls cool air 14 from the environment through the pressed-material mat 2 at an air-cooling station 11.

[0039] For clarity's sake, FIGS. 2 and 3 do not show details of the pressed-material mat and the driven deflection rollers and the intake opening. FIG. 2 differs from FIG. 1 as a possible second embodiment in that the rotating mesh belts 5c and 5f have been omitted. A possibility of this type consists in some types of insulating board, without major losses in the drive load being expected on the at least four endless driven deflection rollers.

[0040] FIG. 3 in turn shows, as a further embodiment, that the long endless mesh belt [5a] according to the invention can also be completely dispensed with. Therefore, only the mesh belts 5b and 5c are shown in the upper part of the apparatus.

[0041] Since, of course, a gap [12] is produced between the zones 1 and 2, even with the deflection rollers 7 of the mesh belts 5b and 5c closely juxtaposed, a slide shoe 13 extending over the full width of the pressed-material mat 2, provided in the gap 12 between two deflection rollers 7 of the two zones 1 and 2 and the pressed-material mat. As a result, the mat of pressed material here cannot expand in this less than 200 mm long gap and be damaged.

TABLE-US-00001 LIST OF REFERENCE CHARACTERS  1 apparatus  2 pressed-material mat  3 calibrating plate 4a-c steamer 5a-f mesh belt 6a-c suction device  7 deflection roller  8 driven roller  9 intake opening 10 height adjuster 11 air-cooling station 12 gap 13 slide shoe 14 cool air Z1, Z2 zone