EP4695487A1

EP4695487A1 - A door panel

Info

Publication number: EP4695487A1
Application number: EP24722069.2A
Authority: EP
Inventors: Tanuwijaya SUSANTO; Bhakti Sadeli
Original assignee: Individual
Current assignee: Individual
Priority date: 2023-04-14
Filing date: 2024-04-12
Publication date: 2026-02-18
Also published as: GB202305491D0; WO2024213897A1

Abstract

The present invention relates to a door panel. The panel may be used as a core in a door or wall or the like and has a high thermal conductivity combined with stability and strength which is energy efficient due to its thermal capacity. The panel comprises a thermally insulating material (2) sandwiched on a front and opposing rear face by a first layer (4, 5, 4, 22) and a second layer (4, 5, 4, 22) and at least one strengthening strip (1) sandwiched by, and in contact with, the first and second layers (4, 5, 4, 22). The arrangement is characterised in that the first and second layers (4, 5, 4) comprise a planar board (5) of material sandwiched on an opposing front and rear face by a first planar layer (4) and a second planar layer (4) arranged parallel to one another. The plane of the boards (4, 5, 4, 22) extends in a longitudinal direction and a lateral direction, perpendicular to the longitudinal direction and the first and second layers (4, 5, 4, 22) are bonded to the at least one strengthening strip (1). The strengthening strip extends longitudinally across the door component and continuously from adjacent one edge of the door component to adjacent an opposing, second, edge of the door component. A method of manufacture of the present invention is also disclosed.

Description

A Door Panel

The present invention relates to a door panel for use in manufacturing a door. The door panel may be used in a door or a wall panel or the like and the present invention further relates, but not exclusively, to a panel having a high thermal conductivity combined with stability and strength which is energy efficient due to its thermal capacity. The panel may comprise biodegradable ecological material with a high responsible usage of natural timber.

Hereafter the application of the panel of the present invention will be described in relation to use as a door core in a door, but it will be apparent to the skilled person, given what is disclosed herein, that the panel could be used in a wall or the like, i.e. any field where strength, thermal performance and ease of manufacture are key design parameters.

There exists many door types and methods of manufacture known in the industry of door manufacture. An aspect of this present invention is of particular relevance to timber doors, preferably external domestic doors in both contemporary and traditional “stile and rail” designs.

A problem associated with the construction of external domestic doors is that it is challenging to achieve improved thermal insulation performance that complies with the UK, and other, building regulations, while maintaining structural integrity and security. The design of a door component, particularly the door core is a key aspect to be considered in meeting those requirements.

The majority of existing timber door cores typically comprise a solid timber core with plywood skins, while traditional stiles and rail doors comprise a solid timber core secured within a frame formed of rails and stiles, with only the panels being thermally insulated by way of polystyrene foam sandwiched between plywood. In both types of construction, preferably a decorative surface veneer can be added for aesthetic purposes.

In order to comply with UK building regulations, external doors must be energy efficient. To meet energy efficiency requirements, timber rail and stile doors are produced with insulating foam sandwiched in the door panels. This, however, compromises the structural integrity and security of the door and does not maximise thermal insulation properties across the door.

The present invention is a breakthrough in the timber door world in that the structure of the core improves stability and thermal insulation capability. An outer layer of wood sheet/plywood provides a strengthening exoskeleton to the construction. The core is able to give thermal conductivity (U-Value) < 1 under current British Standard. Prior art in this area compromises the stability and the durability of a door to get a better II- Value.

By having an arrangement as described herein, the present invention provides the stability across the whole slab and provides more protection from breach.

The closest prior art in this field is an all timber door that uses thermal foam inside. The present invention differs in that the prior art does not comprise panelling as described herein. The prior art are therefore less stable and more vulnerable to being breached.

The present invention can be used as a standard door blank for any door models required. It can also be routed open for glazing purpose with reasonable sizes and locations, without the door losing strength and stability. With some veneer laminating on the door blank it can also be converted to a stile and rail type door while maintaining the stability and a good thermal performance to the door.

The present invention will promote energy efficiency due to its thermal conductivity, will give a secure feeling that comes from the strength, and less worry about cracking and bowing of the door.

According to the present invention there is provided a panel as defined in the appended independent apparatus claim. Further preferable features of the panel of the present invention and of its application as a door or wall are defined in the appended dependent apparatus claims.

According to a further aspect of the present invention there is provided a method as defined in the appended independent method claim. Further preferable features of the method of the present invention are defined in the appended dependent method claims.

An advantage of the present invention over the prior art, is that the combination of the layers together with the strengthening strips and insulating material helps to improve thermal performance while ensuring enhanced structural stability and security. The first and second layers may be formed from a single board material, for example a plywood, medium-density fibreboard (MDF), high-density fibreboard (HDF), possibly using high-moisture resistant (HMR) adhesive and/or wood veneer/laminated veneer lumber (LVL), or modified MDF material, or any other suitable material, such as fiberglass. The modified MDF material may be an MDF material made using a process including acetylation, for example the material sold under the trade mark Tricoya®. The first and second layers may be formed in other ways, in particular, one or both of the first and second layers may be formed from a sandwich arrangement comprising a middle layer first material sandwiched on the front and rear face by a second material. The first material (middle layer) may be a metal sheet, for example an aluminium sheet or aluminium wiremesh added with fire (heat) resistant layer (if desired) and the second material may be plywood, MDF, HDF, HMR and/or wood veneer/LVL, or modified MDF material, or any other suitable material, such as fiberglass. This arrangement greatly improves the stability and security of the door component and a door fabricated from, or including, such a door component. Ply board is a known material made by laminating sheets, particularly wood sheets, together to form a board.

The first and second layers are preferably formed by substantially planar boards, particularly ply boards which may be cross ply boards, which may be arranged such that they are substantially parallel to one another. The plane of the boards may extend in a longitudinal direction and a lateral direction, perpendicular to the longitudinal direction. The boards may be offset in a depth direction perpendicular to the boards.

The at least one strengthening strip is preferably sandwiched by, and makes contact with, each of the first and second layers. The first and second layers may be bonded, or otherwise attached, to the, or each, strengthening strip, for example by gluing. The strengthening strip may extend across the door component substantially parallel with the lateral direction. The strengthening strip preferably extends substantially continuously from adjacent one edge to adjacent an opposing, second, edge of the door component.

In an embodiment, a door component according to the invention comprises a cross laminated strengthening strip reinforced thermally insulating material which is sandwiched between cross laminated timber sheet.

The at least one strengthening strip is preferably an engineered wood product made of crosslaminated LVL (Laminated Veneer Lumber) or LVB (Laminated Veneer Board) with a grain preferably extending in a grain direction, which may be aligned to be substantially parallel with the longitudinal direction. The thermal insulating material may be provided in any form. The thermally insulating material may be provided as a plurality of elongate blocks of foam material. Ideally, the plurality of elongate blocks are arranged parallel to one another, with neighbouring blocks separated from one another by at least one strengthening strip, preferably by one strengthening strip. Each of the plurality of elongate blocks may extend continuously from a position adjacent a top edge of said door component to a position adjacent a bottom edge of said door component, wherein the first edge is opposite the second edge.

At least one, and preferably each, of the plurality of elongate blocks may have a uniform cross- sectional size and shape along the entire length of the block. Ideally, said shape is rectilinear and preferably is a rectilinear polygon, and more preferably is a square or rectangle. Each of the plurality of elongate blocks may be located with an interference fit between the first and second layers. In this way, the blocks tend to be held in position between the layers. Furthermore, each of the plurality of elongate blocks may be compressed by the remainder of the door component and/or may be compressed by the first and second layers. For example the foam blocks may have a depth in the depth direction which is substantially equal to, or slightly greater than, the depth of the at least one strengthening strip.

It is preferable that the arrangement of the first and second layers with the or each strengthening strip is such as to provide at least one elongate cavity into which an elongate block may be arranged, for example by being pushed from one end of said cavity to an opposite end thereof. The or each cavity may have a uniform cross-sectional size and shape along its length which is substantially the same as that of the respective elongate block to be received in said cavity.

The at least one strengthening strip preferably has a greater stiffness than the thermally insulating material.

As noted above, the door component can be used in the manufacture of a door. The door component can be used to manufacture parts of the door, or can be used as a door core.

A second aspect of the invention therefore provides a door comprising a door component as set out above. It should be noted that a door component may be fabricated by creating a precursor component which can be cut to a reasonable desired size and/or shape and may have openings cut therein to receive further components which will make up a door.

A further aspect of the present invention provides a method of manufacturing a door component, wherein the door component is as described above. The method comprises the steps of: a. Arranging the first and second layers with the or each strengthening strip so as to provide at least one elongate cavity into which an elongate block may be pushed; and b. Pushing an elongate block into at least one elongate cavity.

This arrangement allows the first and second layers to be attached to the strengthening strips to provide a carcass into which the insulating material can be added. In an alternative method the method comprises the steps of: a. Providing a first layer on which is arranged the or each strengthening strip so as to provide at least one elongate cavity into which an elongate block may be arranged; b. Arranging an elongate block into at least one elongate cavity; and c. Arranging the second layer so as to sandwich the strengthening strip and thermally insulating material.

Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:

Figure 1 is a schematic side view of a first embodiment of a panel according to the present invention showing cross-sectional views (i-i), (ii-ii), and (iii-iii);

Figure 2a is an exploded perspective view of a part of the first embodiment of Figure 1 ;

Figure 2b is an exploded perspective view showing front and rear planar sandwiched layers according to the first embodiment;

Figure 3 is a perspective view of that shown in Figures 2a and 2b, now non-exploded;

Figure 4 is a schematic side view of a panel of the present invention applied to create a door, showing cross-sectional views (i-i), (ii-ii), and (iii-iii);

Figure 5 is a perspective view of that shown in Figure 4;

Figure 6a is an exploded perspective view of a part of the second embodiment of a panel; and

Figure 6b is an exploded perspective view showing front and rear planar sandwiched layers according to the second embodiment of a panel.

A schematic perspective view of an embodiment of the present invention is shown in Figure 1 , with exploded views shown in Figures 2a and 2b, the embodiment is in the form of a panel 10 wherein outer boards/panels comprising a middle panel (5) sandwiched by front and rear panels (4) are combined with thermal insulating substantially rigid foam sheets/blocks (2) and cross laminated strengthening strips (1).

The thermal insulating substantially rigid foam blocks (2) extend longitudinally from the top to the bottom of the door and a plurality of them are positioned parallel and adjacent to each other. Each foam block (2) is separated by a strengthening strip (1) which may be made from plywood, MDF, HDF, HMR, Wood Veneer / LVL. The outer boards are positioned on the front and rear faces of foam blocks to create a rectangular door core. The outer boards comprise a middle panel (5) of metal sheet or mesh with or without heat insulation, sandwiched by front and rear panels (4) of plywood, MDF, HDF, HMR, Wood Veneer / LVL.

The sheets of the outer boards (4,5,4) are compressed, glued, laminated together, and can be furnished with timber veneer, GRP skin, or any door skin, for a high quality decorative finish. It will be understood that the strength and stability of the panel construction are improved by lamination of the outer timber sheet.

In the illustrated embodiment, the centre of the panel 10 is filled with substantially rigid sheets/blocks (2) of insulating foam. The foam sheets (2) are arranged with a configuration so as to extend vertically (when arranged in a use position in a hung door). The length of the insulating foam (2) is such that the foam extends from adjacent a first edge of the outer boards (4, 5, 4) to adjacent a second edge of the outer boards (4, 5, 4). The second edge is opposite the first edge (e.g. see Figures 1 or 2a & 2b). It will be appreciated that other insulating materials can be used in place of or in addition to the rigid foam sheets.

In the present embodiment, neighbouring foam sheets (2) are separated from one another by strengthening strips (1), which are in this case cross laminated, but need not be. The size of the strengthening strips is dependent on the thickness of the door. Variations in this size are possible. The length of the strengthening strips (1) is such that the bars extend from adjacent a first edge of the outer boards (4, 5, 4) to adjacent a second edge of the outer boards (4, 5, 4). The second edge is opposite the first edge. In the illustrated embodiment, said strengthening strips (1) are equally spaced apart across the horizontal width of the door (when arranged in a use position in a hung door). However, it will be accepted that the strengthening strips can be unequally spaced along the horizontal width of the door. The number of strengthening strips (1) across the horizontal width of the door (as described above) depends on the width of the door itself. Preferably, the strengthening strips (1) are spaced apart by between about 30 mm to 100 mm.

In an embodiment the strengthening strips are spaced apart by between 30mm to 100mm. It should be noted that a preferred range of 30mm to 100mm has been found to provide among the best II values whilst still maintaining the structural strength and stability of a door.

Figure 4 is a perspective view of a door (20) comprising the panel (10) of the first embodiment. As shown in Figure 4, the rail (3) (or stile) comprises insulating foam sheets/blocks (2) sandwiched between outer timber boards (4, 5, 4) and metal sheet (with or without heat insulation) and, in the assembled door (20), said rail or stile (3) may be framed, in this case with a door lipping (6) around the (typically, four) edges of the boards (4, 5, 4). In an assembled door (20), a decorative veneer or any door skin (7), for example a cross banded veneer, may be provided on to the outer plane surfaces of the door boards (4, 5, 4) (see Figure 5). The decorative veneer may be any suitable veneer, for example an oak veneer, but it will be appreciated that other materials can be used in place of the outer decorative oak veneer and could be a synthetic material, for example a glass reinforced plastic (GRP) material.

A door (20) as shown in Figure 5 is assembled by securing together a plurality of rails (3), stiles (5) and panels (4, 5, 4) that are manufactured separately.

It will be appreciated that by varying the thickness of the insulating foam layer, a door can have different thickness which will be understood to improve thermal insulation while ensuring enhanced structural integrity and security.

The present invention is not limited to the specific embodiments described above and it will be understood that features disclosed as part of one embodiment can, if appropriate, be used in combination with other embodiments. Alternative arrangements and suitable materials will be apparent to a reader skilled in the art.

Figures 6a and 6b show exploded perspective views of a parts of the second embodiment of panel, for example a door panel. The second embodiment is essentially identical to the first embodiment shown in Figures 2a and 2b, with the difference being that the outer boards/panels (22) are fabricated from a single board rather than the 3-layer structure (4, 5, 4) of Figures 2a and 2b. The material from which the outer board is made in this example comprises a modified MDF material, for example an MDF material made using a process including acetylation, for example the material sold under the trade mark Tricoya®. In other examples, the material from which the outer board is made may comprise plywood, MDF, HDF, HMR, Wood Veneer or laminated veneer lumber, or fiberglass.

Claims

1. A panel comprising: a thermally insulating material (2) sandwiched on a front and opposing rear face by a first layer (4, 5, 4, 22) and a second layer (4, 5, 4, 22); and at least one strengthening strip (1) sandwiched by, and in contact with, the first and second layers (4, 5, 4, 22), and characterised in that: the first and second layers (4, 5, 4, 22) comprise a planar board (5, 22) of material; wherein the plane of the first and second layers (4, 5, 4, 22) extends in a longitudinal direction and a lateral direction, perpendicular to the longitudinal direction, and the first and second layers (4, 5, 4, 22) are bonded to the at least one strengthening strip (1), the strengthening strip extends longitudinally across the door component and continuously from adjacent one edge of the door component to adjacent an opposing, second, edge of the door component.

2. A panel as claimed in claim 1 , wherein the thermally insulating material is a foam material.

3. A panel as claimed in claim 1 or 2, wherein the thermally insulating material is provided as a plurality of elongate blocks of foam material.

4. A panel as claimed in claim 3, wherein the plurality of elongate blocks are arranged substantially parallel to one another, with neighbouring blocks separated from one another by at least one strengthening strip (1).

5. A panel as claimed in any one of claims 3 or 4, wherein at least one of the plurality of elongate blocks has a substantially uniform cross-sectional size and shape along the entire length of the block.

6. A panel as claimed in any one of claims 3 to 5, wherein each of the plurality of elongate blocks locates with an interference fit between the first and second layers.

7. A panel as claimed in any one of claims 3 to 6, wherein each of the plurality of elongate blocks is compressed by the first and second layers.

8. A panel as claimed in any one of claims 3 to 7, wherein the arrangement of the first and second layers with the or each strengthening strip is such as to provide at least one elongate cavity into which an elongate block may be pushed from one end of said cavity to an opposite end thereof.

9. A panel as claimed in claim 8, wherein the or each cavity has a uniform cross-sectional size and shape along its length which is substantially the same as that of the respective elongate block to be received in said cavity.

10. A panel as claimed in any of the preceding claims, wherein the planar board (22) of material is one of plywood, MDF, HDF, HMR, Wood Veneer or laminated veneer lumber, modified MDF, or fiberglass.

11. A panel as claimed in any of claims 1 to 9, wherein the planar board (5) of material is sandwiched on an opposing front and rear face by a first planar layer (4) and a second planar layer (4) arranged parallel to one another.

12. A panel as claimed in claim 11 , wherein the planar board material is metal.

13. A panel as claimed in claim 12, wherein the planar board is a metal sheet.

14. A panel as claimed in claim 12, wherein the planar board is a mesh.

15. A panel as claimed in claims 13 or 14, wherein the planar board further comprises heat insulator.

16. A panel as claimed in claim 12, wherein the metal is aluminium.

17. A panel as claimed in any of claims 11 to 16, wherein the first and I or second planar layer material is one of plywood, MDF, HDF, HMR, Wood Veneer or laminated veneer lumber, modified MDF, or fiberglass.

18. A panel as claimed in any of the preceding claims, wherein the at least one strengthening strip has a greater stiffness than the thermally insulating material.

19. A panel as claimed in any of the preceding claims, wherein each of the door components forms one of: a door panel, a door rail and a door stile.

20. A panel as claimed in any of the preceding claims, wherein the edges of the door are framed by a framing layer.

21. A panel as claimed in claim 20, wherein the framing layer is made of wood.

22. A door comprising a panel according to any of the preceding claims.

23. A door as claimed in claim 22, in which a decorative veneer is provided on outer surfaces of the first and second layers.

24. A door as claimed in claim 23, in which the decorative veneer is a cross banded veneer or glass reinforced plastic material.

25. A wall comprising a panel according to any of the preceding claims.

26. A method of manufacturing a panel, the method comprising the steps of: arranging the first and second layers with the or each strengthening strip so as to provide at least one elongate cavity into which an elongate block may be pushed; and pushing an elongate block into at least one elongate cavity.

27. A method according to claim 26, further comprising the steps of: providing a first layer on which is arranged the or each strengthening strip so as to provide at least one elongate cavity into which an elongate block may be arranged; arranging an elongate block into at least one elongate cavity; and arranging the second layer so as to sandwich the strengthening strip and thermally insulating material.