IE62852B1

IE62852B1 - Method and apparatus for manufacturing sandwich panels

Info

Publication number: IE62852B1
Application number: IE37191A
Authority: IE
Inventors: Esko Brunila; Lars-Henrik Heselius; Tarmo Willman
Original assignee: Partek Ab
Priority date: 1990-09-04
Filing date: 1991-02-04
Publication date: 1995-03-08
Also published as: IE910371A1; RU2066635C1; CZ27791A3; SK280243B6; FI86160C; SK27791A3; EE03061B1; LV11017B; FI86160B; UA26975A1; JP3116054B2; FI904370A0; JPH05345400A; PL289001A1; PL166702B1; GB2247643A; YU48170B; GB9118671D0; LV11017A; CZ280840B6

Abstract

The invention relates to manufacturing sandwich panels with a core of binder cured lamellas of mineral wool whose main grain is perpendicular to the main plane of the panel, the individual lamella layers being displaced lengthways in relation to one another so that joints between successive lamella pieces in adjacent lamella layers fall in different lines across the lamella core.

Description

METHOD AND APPARATUS FOR MANUFACTURING SANDWICH PANELS The invention relates to a method for manufacturing sandwich panels consisting of a core of mineral wool lamelias and surface layers of material suitable for construction purposes, e.g. sheet metal; to be precise, a method according to the ingress of patent claim 1.

The invention also relates to an apparatus for performing of the method; to be precise, an apparatus according to the ingress of patent claim 8.

When manufacturing sandwich panels with a core of mineral wool the core is built up so, that its main surfaces or the surface layers are coated with glue, whereafter the surface layers are placed on the core. Generally, the work is performed manually and is therefore extremely time consuming.

There is, however, a method for manufacturing sandwich panels with mineral wool core mechanically, known i.a. from the German patent application DE,A 38 24 842. According to this method panels are sawn off from a continuous sandwich consisting of a core of transverse glass wool lamelias with surface layers of sheet metal. Polyurethane glue is injected between the three layers which are fed forward continuously; between the core and the top layer and the core and the bottom layer. The three layers are brought together between two endless conveyor belts and bound together by polymerization of the glue into a sandwich product.

The object of this invention is a new procedure for automated manufacture of long sandwich panels for construction purposes. The term long refers to lengths of up to ca 12 meters. In order to obtain sufficient product strength for panels used as structural elements, the core is built up of longitudinal lamellas. These lamellae may be made up of several lamella pieces. Another object of the invention is an apparatus for performing the above mentioned method.

The two objects are achieved by the method and the apparatus defined -in the introduction of this description combined with the characteristics stated in the patent claims 1 and 8 respectively.

By the method according to the invention, the sandwich panel is manufactured of lamella pieces that are sawn from a sheet of cured mineral wool. The pieces are turned through 90° around their longitudinal axes and moved to a mat consisting of lamellas going to form, a lamella core. The individual lamella pieces in each lamella in the lamella core are brought together with the preceding lamella piece under application of pressure, and lamellas lying side-by-side are also brought together under application of pressure. The ends of the lamella pieces are preferably given a shape other than straight cross cut, such ends fitting against each other, whereby the joint becomes stronger.

The lamella pieces and the lamellas built up of lamella pieces are displaced lengthways in relation to the adjacent lamellas, so that the joints are not in line across the lamella core.

The lamella core may be put together in different ways. According to one preferred version, a group of pieces, e.g. 46 pieces, are separated from a series of adjacent lamella pieces that have been turned around their longitudinal axes, and displaced by means of a displacement means longitudinally towards the preceding group of lamella pieces that have already been displaced. The displacement means comes into contact with lamella pieces gradually so that the outer piece, for example, at one side of the group comes into the contact and starts moving first and the outer piece at the opposite side of the group comes into contact with said means and starts moving last. In this way, the individual lamella pieces adjacent each other are displaced lengthways in relation to each other, and the joints between the lamella pieces in lamellas adjacent each others are spread over the lamella core. The contact surface of the displacement means, bearing on the ends of the lamella pieces, is preferably stepped, but it may also have a more irregular shape.

When the mat growing up from groups of lamella pieces pressed against each other has reached a sufficient length, it is sawn off crosswise and moved to the lamella core being built up. Thereafter, building up a new mat of displaced lamella pieces by means of the displacement means may be started. Naturally, the width of the mat may correspond with the width of the core and the core, then, is built up without the sideways movement of the mat.

Each individual lamella piece in the group of lamella pieces can be displaced separately. Alternatively, each lamella In the cor® can be built up separately and pushed towards the semifinished core.

When the lamella core has reached its final dimensions, it is held together and moved to a position where it is brought on the lower surface layer which already has been profiled and coated with a suitable glue. The laminate so built is transferred to the next station where the upper surface layer, profiled and coated with glue, is brought on the core from above. Thereafter, the sandwich element is cured in suitable temperature and pressure conditions.

The lame 11 core can be brought on the lower surface layer in different ways. The lame 11 core might e.g. be slipped down to the inmovable surface layer from its support plate that is. gradually pulled away from beneath the core. Another possible method is to give the core a movement, e.g. by means of a conveyor which does not move from its location but makes the core slip down over the edge of the support to the surface layer that is placed under the core support and has been given a movement in the same direction and with the same speed as the core.

The sandwich panel manufactured according to the invention is an excellent construction unit. It can be used for floors, ceilings and internal or external walls. Thanks to its large dimensions, It simplifies construction work and it is also very advantageous from a architectonic point of view.

The different dimensions of the sandwich panels can easily be varied by feeding the relevant information into the memory of the processor unit of the manufacturing device. Thicker panels can be obtained by Increasing the width of the sawn lamella pieces accordingly. For a thicker panel, a greater length of cured mineral wool sheet is required, as fewer lamella pieces are obtained from the same width of sheet. The length of the panel can be varied by adjusting the device to request longer lamellas, i.e. more lamella pieces of the same length in the eacl lamella, or the same number but longer lamella pieces in each lamella. The number of joints between the lamella pieces and the spread of joints over the lamella core do however affect the strength of the panel. A change in the width or length of the panel requires similar change in the dimensions of the surface layers.

In order to achieve products of first class quality, dimension discrepansies should be kept within very tight limits. The contiguous side and end surfaces of the lamella pieces should be smooth, and especially the end surfaces must be of exactly corresponding shapes, so that te ability of the pieces in a '4 lamella and lamellas in the core to hold together is not impaired, affecting the strength values.

The method allows manufacture of sandwich panels, whose cores consist of longitudinal mineral wool lamellas arranged side by side. The lamellas may consist of a single piece or two or more lamella pieces joined end to end. The end surfaces can be grooved or mechanically treated in another way to provide a hold between the snd surfaces. Even glueing may be used. Preferably, the adjoining end surfaces should be bevelled or shaped in some other way so that they make a strong joint when brought together.

The preferable surface material, is thin sheet of metal, which preferably is bent at its edges and is cut to the desired length synchronizely eith the building up of the lamella core. The metal sheet may even be profiled over its entire surface.

The preferable substance for attaching the lamella core to the surface layer is polyurethane glue. It is applied to the inner sides of the surface layers and, when subject to heat and pressure during curing the element, it forms a foam layer betwen the surface layer and the lamella core. The foam layer fills any irregularities between the surface of the lamella core and the surface layers.

Described below is a preferable example of the method and the device according to the invention, with reference to the enclosed figures, of which figure 1 shows schematically building up a lamella mat, which is a part of a lamella core, in which fig. la shows sawing of lamella pieces from a sheet of cured mineral wool, seen from above, fig. lb shows from the front and in cross section sawn lamellas, the process of turning them around their longitudinal axis and placing them against a lateral stop, fig. lc shows the longitudinal displacement of a group of lamella pieces against a corresponding group of lamella pieces that were displaced in the preceding stage; figure 2 shows, schematically, five different stages in the process of bringing the surface layers to the lamella core, from the front and in cross section, in which fig. 2a‘ shows the lamella core on Tts conveyor belt before it is moved to the adjoining stage, and with the device for applying the glue in position above the lower surface layer, fig. 2b shows the lamella core in position just before the adjoining station, (for clarity, the gluing device is shown in figures 2a and 2e only), fig. 2c shows the lamella core on its support and feeding plate, in position above the lower surface layer.which is raised into position close to the support plate, fig. 2d shows the lamella core on its support plate above the surface layer as in fig. 2c, but with the pusher returned to its starting position and side supports in operating position, just before the support plate is pulled aside so that the lamella core drops down onto the lower surface layer, and fig. 2e shows the upper surface layer with is glued surface, being turned down onto the upper surface of the lamella core.

Figure 1 a shows a sheet of mineral wool (A) being sawn into lamella pieces (a) by conventional mineral wool saws (1).

Figure lb shows the lamella pieces in a position where a pusher (2) pushes them - in the figure to the right - to be turned through 90° around their longitudinal axes and then to form a strip (B) of turned lamella pieces bearing sideways on a lateral stop. Figure lc shows a strip (B) under building, from above. A displacement device (3) has separated the five outer lamella pieces and displaced them lengthways towards a group of five lamella pieces which were displaced lengthways in the previous stage of the formation of a lamella mat (C). The stepped contact surface of the displacement device (3) gives the group of lamella pieces a corresponding displacement. This phase displacement leads to the joints being spread over the surface of the lamella core instead of forming a straight line. The leading edge of the lamella mat (C) bears on a movable stop (4). When a sufficient-number of groups of turned lamella pieces, one after another, has been pushed against each other in the mat (C), the length of the mat exceeds the desired length of the lamella core, and the cutting device (5) cuts the mat (C). The cut section of the mat is pushed to the lamella core under building which may consist of one or more mats (C) side by side. The movable stop (4) returns to the cutting place, to form a stop for the small stump of the following lamella mat (C)» According to figure 2, the lamella core (K) consists of two mats (C) side by side with a total of 10 turned lamellas. Each lamella in the core consists of two cut lamella pieces or of one whole lamella piece and two cut pieces.

The lamella core (K) is built up on th® base (6), where a lateral displacement device, the pusher (7), is ready to push the lamella core over to its feed plats (8), The feed plate (8) consists of two longitudinal sections (8a and 8b) moving at right angles to the length of the lamella core and its direction of manufacture. The two sections of the feed plate (8a, 8b) move towards each other, so that they meet directly above the surface layer, and away from each other so that they give access to the lower surface layer (lla) on its conveyor belt (9). In the position in figure 2a, the sections (8a, 8b) are on each side of the surface layer and the section 8a, which has an extension towards the lamella core's base (6), is ready to receive the lamella core (K). The lower surface layer (Ila) lies on the conveyor belt (9) and is coated with a layer of glue by means of of the glueing device (12a). The side guides (10a, 10b) are still in their working position after making the previous sandwich panel.

In the following stage, figure 2b, the pusher (7) has displaced the lamella core sideways over to the left feed plate section (8a), at the same time as the right feed plate section (.8b) z moved left to the position where it receives the lamella core. Meanwhile, the left side guide (10a) has been raised to an inactive position, so that it does not obstruct the lamella core being moved to a position above the lower surface layer (Ila).

In the following stage, figure 2c, the lamella core has been transferred to the feed plates (8a, 8b) that meet in the middle above the lower surface layer, and the pusher is still in its extreme position, where it is holding the lamellas in the lamella core pushed against the right side guide (10b). The left side guide (10a) is on its way to its lower, working position. Meanwhile, the lower surface layer (Ila) on its conveyor (9) has been raised to a position as close as possible / to the feed plates (8a, 8b).

Figures 2a -2c show that moving the lamella cor® over to a position above the surface layer (Ila) consists of a) displacement by means of the pusher (7) a distance equivalent to the width of the lamella core, b) lateral transport of the feed plate section (8a) a distance equivalent to half the width of the lamella core, and c) displacement by means of the pusher (7) onto the other feed plate section (8b) a distance equivalent to half the width of the lamella core. It is obvious that the lateral displacement has taken place in a way that saves both energy and equipment.

In the following stage, figure 2d, the pusher (7) has returned to its starting position outside the lamella core's base (S), and the side guide (10a) is in its lower working position.

Immediately after this position has been adopted, the feed plate sections (8a, 8b) are pulled outwards and the lamella 5 core is sinking onto the lower surface layer. Said sinking of the core onto the lower surface plate is thus started in the middle of the element, where the feed plate sections 8a and 8b successively leave the core without support. Thus the bringing 'together of the lamella core and'the surface layer is taking place place in diminutive movements and is thus completely controlled.

After that the lamella core with attached bottom surface layer is moved on the conveyor (9) between the side guides (10a,10b) to the station where the upper surface layer is applied. Figure 2e shows how the upper surface layer (11b) is coated with a layer of glue by means of the glueing device (12b), after which the surface layer is turned up and down onto the lamella core.

Devices suitable for performing the alternatives for buiding up the lamella core, given in the general part of the description, do not differ fundamentally from the devices described above.

Claims

1. A method for continuous manufacturing of sandwich panels with a core (K) of binder cured longitudinal lamellas (L) of mineral wool, whose main grain is perpendicular to the main plane of the panel, and with surface layers (lla, 11b) made of material suitable for construction purposes, e.g. sheet metal, whereby the surface layers are joined to the core by means of an attachment layer, and whereby lamella pieces (a), with a width equivalent to the thickness of the core, are sawn from a sheet (A) of mineral wool, turned 90° around their longitudinal axes and assembled, side by side and end to end to form a lamella mat consisting of the number of lamella pieces that correspond to the dimensions of the panel, with at least the end surfaces of the pieces that touch each other being shaped to fit together preferably by other than a straight cross cut, and smoothed, characterized in that the individual lamellas are displaced lengthways in relation to each other so that joints between successive lamella. pieces (a) in adjacent lamellas (L) do fall in different lines across the lamella core (K), that the lamella core, consisting of lamellas that are built up of joint lamella pieces, mutually displaced, and pressed together lengthways and crossways, is held together and moved to a position above the first surface layer sheet (lla) provided with an adhesive layer on its upturned side, after which the sheet and the core are joined and attached to each other, and that the second surface layer sheet (lib) is provided with an adhesive layer on its upturned side, turned and applied from above to the upper side of the core.

2. A method according to claim 1, whereby a group (B) of adjacent and axially turned lamella pieces (a) is displaced lengthways to form a lamella mat (C) together with previous and/or following groups of lamella pieces, characterized In '4 that each lamella piece (a) in the group is pushed against the end surface of the corresponding lamella in the previous group, where the lamella pieces have already been longitudinally displaced, so that the adjacent lamellas in the group are phase displaced in relation to each other along their adjoining sides, that the lamella mat (C), consisting of groups of lamella pieces one after another, is cut crosswise, whereby the front of the lamella mat, when seen in the direction of the'movement, bears on a movable stop (4) and the phase displaced rear end, laying behind the cutting station, when seen in the direction of the movement, forms a stop for the following group of lamella pieces, and that, if necessary, th® cut-off lamella mat (C) is moved aside to build up a lamella core of desired width, after which the lamella core is moved to the station for adjoining of panel layers.

3. A method according to any of the preceding claims, characterised in that the surface layer sheets (Ila, lib) are cut to the sise of panel and shaped while moving from a storage roll to the panel adjoining station.

4. A method according to any of the preceding claims, characterised In that the lamella core unit (K) Is moved above the first surface sheet (Ila) by means of a movable support (8), and the core Is laid down on the immovable surface sheet by pulling away the support. 5. A method according to claim 4, characterised in that the laying down of the core is started in the middle of the panel. 6. A method according to any of the claims 1-3, characterised in that the lamella core unit (1C) is moved, above the first surface sheet (Ila) by means of a support (8) that gives the core unit a movement, and the adjoining of the core and the surface sheet is accomplished by giving £ both the core and the surface layer a movement in the same direction and of the same speed, whereby the core is pushed over the edge of the support and is laid down on the surface sheet. 7 . A method according to any of the preceding claims, characterised in that the lamella core (X) is subject to pressure sideways perpendicular to the length of the lamellas (L) while being transferred onto the first surface sheet (Ila). 8. An apparatus for continuous manufacturing of sandwich panels with a core (X) of binder cured longitudinal lamellas of mineral wool, whose main grain is perpendicular to the main plane of the panel, and with surface layers (Ila, lib) suitable for construction purposes, e.g. sheet metal, said surface layers being joined to the core by means of an attachment layer, including means (1) for cutting lamella pieces (a) from a web or sheet (A) of mineral wool, turning the pieces through 90° around their longitudinal axes, means for forming the end surfaces of the lamella pieces and/or giving them a shape other than a straight cross cut allowing the ends to fit tightly against each other when coming into the contact, means for assembling the lamella pieces to form a core unit (K) of desired dimensions, where joints between successive lamella pieces in adjacent lamellas do fall in different lines across the lamella core, and devices (12a, 12b) for applying an adhesive layer to the inside of the surface layers and attaching them to the core, which devices are mutually synchronized, characterised in a device (3) for displacing and adjoining the individual lamella pieces (a) to build up longitudinal lamellas, a device (5) for cutting the lamellas to the desired length against a movable stop (4), devices (7, 10a, 10b) for moving the lamella core unit (X) onto a support (8) above the first surface layer (Ila) and holding the core laterally compressed, while it is laved down on the surface layer, and devices for turning up the horizontal second surface layer (lib) provided with the adhesive and applying it to the upper side of the lamella core. S. An. apparatus according to claim 8, characterized in that the device (3) for displacement of lamella pieces has a stepped contact surface with the width of each step corresponding to the width of a turned lamella piece (a) .. 10. An apparatus according to claim 8 or S f characterised in that the cutting device (5) is arranged to cut one or more lamellas at the same time. 11. An apparatus according to any of claims 8-10, characterized in that after an accomplished cut the movable stop (4) is arranged to move back to the cutting station (5), and after that move gradually forwards, in the direction of the movement of the lamella mat, to the point where the distance between the cutting station and the stop corresponds to the length of the lamella core (K). 12. An apparatus according to any of the claims 8-11, characterized In that the support (8) consists of two longitudinal sections (8a, 8b) that are movable to and from each other across the length direction of the lamella core. 13. An apparatus according to claim 12, characterised in that the two sections (8a, 8b) of the support are arranged to move a distance equivalent to half the width of the lamella core, at least. 14. An apparatus according to any of the claims 8-13, characterised in that the functioning of the devices comprising the apparatus is controlled by a computer. -1415. A .method for continuous manufacturing of sandwich panels according to any preceding claim substantially as hereinbefore described with reference fo and as illustrated in the accompanying drawings.

5. 16„ ' An apparatus for continuous manufacturing of sandwich panels according to any preceding claim substantially as hereinbefore described with reference to and as Illustrated in the accompanying drawings. F. R- KELLY & CO., AGENTS FOR THE APPLICANTS.