GB2608150A

GB2608150A - Door assembly and method of its manufacture

Info

Publication number: GB2608150A
Application number: GB2109049.3A
Authority: GB
Inventors: Henry David Wicks Matthew
Original assignee: Doorstore Wirral Ltd
Current assignee: Doorstore Wirral Ltd
Priority date: 2021-06-24
Filing date: 2021-06-24
Publication date: 2022-12-28
Also published as: GB202109049D0

Abstract

A door assembly 10 includes a door shell comprising a first and second opposite panel (14, fig 3), a first side member 16a, a second side member 16b, a top rail member 18a and a bottom rail member 18d. These components are arranged to form a void 20a-c. An eco-friendly material filling 22a-c is provided within the void. The eco-friendly material may be treated with flame retardant chemicals and/or may provide sound proofing. The panels may be formed from high density fibreboard or medium density fibreboard or glass-reinforced polyester. In a second aspect, an insulation panel is formed from expandable cork or mycelium. In a further aspect a method of forming a door assembly is provided.

Description

DOOR ASSEMBLY AND METHOD OF ITS MANUFACTURE

TECHNICAL FIELD OF THE INVENTION

This invention relates to a door assembly and its method of manufacture. In particular, this invention relates to a door assembly providing the necessary security, safety and access control, but which also utilises a novel assembly of eco-friendly construction materials providing excellent mechanical strength, insulation and acoustic-absorbing properties. The door assembly being more sustainable and environmentally-friendly to produce, and which finds particular application as interior wooden doors, interior fire-rated doors and exterior composite (GRP) doors.

BACKGROUND

It has been known for many years to manufacture internal doors using a variety of techniques which largely aim to replicate the aesthetic appearance of a solid wood door. Such doors are much cheaper to manufacture than solid wood doors, and hence more affordable for the consumer to purchase.

These types of internal doors generally consist of a sandwich-like construction in which panelling or outer skins, usually made of high density fibreboard (HDF), medium density fibreboard (MDF) or other engineered materials, enclose an inner structural framework. Between the panelling there may be a hollow core, or, more usually, a material filling or stuffing is provided which completely fills the voids within the door to provide mechanical rigidity, insulation and acoustic-absorbing properties, and/or fire resistance.

These internal doors can be configured as flush doors, which are the simplest of all door designs comprising panelling on both sides, or panel doors which are the most common style of internal door having a series of either horizontally-or vertically-stacked panels which can give a more traditional aesthetic appearance to the door. Interior doors, in this context, includes full-sized standard doors for the home, and fire doors (both commercial and residential).

Glass Reinforced Polyester (GRP) doors, which are also known as composite doors, have a very similar construction to such internal wooden doors, but instead of an MDF outer facing, front and rear GRP skins are applied on either side of the core stuffing, as well as top, bottom and side edge bands which provide a waterproof construction, and which can be used as an external door.

The core stuffing filling the void between the paneling generally comprises three types: solid, hollow or stave. A solid core is a solid sheet of material, such as particle board, cardboard, chipboard or foam, that is used to completely fill the space between the two outer facings. The resultant door assembly often having desirable mechanical strength, insulation and soundproofing properties. Fire-resistant solid cores can also be provided which have been treated with flame-retardant chemicals or the like, or include a non-combustible material filling.

It is also known to utilise hollow cores, which may feature only nominal support in the void between the door facings and the framework, often in the form of corrugated cardboard. Stave core doors lie somewhere between solid and hollow cores in terms of partitioning attributes and properties, and hence cost. They are generally constructed from wooden slats stacked one on top of the other.

The problem with using particle board, cardboard, chipboard or foam as a core stuffing material is that it has very poor eco-credentials, requiring a significant amount of energy and resources to produce. Perhaps more importantly, particle board also contains significant amounts of chemicals (for adhesives and treatments), and there are often questions around the traceability of the wood from which it is produced.

Therefore there is the need for a door assembly and its method of manufacture that provides the necessary mechanical rigidity, insulation, and sound-proofing properties in an economical product, but one which also utilises a novel assembly of eco-friendly construction materials, and being more sustainable to produce and transport.

It is an object of the present invention to provide a door assembly and its method of manufacture which overcomes or reduces the drawbacks associated with known products of this type. The present invention provides internal and external door assemblies that utilise ecofriendly core materials to provide excellent mechanical strength, insulation and soundproofing properties. It is a further object of the present invention to provide a method of manufacturing such door assemblies.

SLUM/IRV OF THE IN FEM 70N The present invention is described herein and in the claims.

According to the present invention there is provided a door assembly, comprising: a door shell comprising a first panel and an opposite second panel, a first side member, a second side member, a top rail member and a bottom rail member, wherein the first panel, the second panel, the first side member, the second side member, the top rail member and the bottom rail member being arranged to form a void; and an eco-friendly material filling within the void.

An advantage of the present invention is that the novel eco-friendly material filling formed within the void are much more sustainable and environmentally-friendly to produce, and yet provide excellent mechanical strength, insulation and acoustic-absorbing properties, and/or fire resistance.

Preferably, the first and second panels being formed from high density fibreboard (HDF) or medium density fibreboard (MDF) or Glass Reinforced Polyester (GRP) or other engineered or natural materials.

Further preferably, the first and second panels being decorative enabling the door assembly to mimic the appearance of a solid wood door.

In use, the first and second panels may further comprise decorative grooves routed in the outer faces thereof and/or pressed or embossed decorative panels.

Preferably, the door shell further comprising a first lock stile which abuts against the first side member and a second lock stile which abuts against the second side member, and being positioned generally equidistant between the top rail member and the bottom rail member.

Further preferably, the door shell further comprising one or more rail members interposed between the top rail member and the bottom rail member.

In use, the door shell may further comprise two rail members interposed between the top rail member and the bottom rail member, and being arranged to form three voids in the door shell.

Preferably, the side members, the rail members and the lock stiles being formed from solid wood.

Further preferably, the panels, the side members, the rail members and the lock stiles being screwed, joined, adhered or affixed together.

In use, the outermost faces of the first side member, the second side member, the top rail member and the bottom rail member may be covered by a veneer or receive a painted finish.

Preferably, the door assembly being an interior wooden door, interior fire-rated door or exterior (GRP) composite door.

In use, the door assembly may further comprise one or more glazing panels.

Further preferably, the eco-friendly material filling being expandable cork.

In use, the eco-friendly material filling may be mycelium.

Preferably, the eco-friendly material filling being obtainable from natural fungal growth which converts a nutrient feedstock into a sustainable synthetic construction material.

Further preferably, the nutrient feedstock is selected from the group consisting, but not limited to, any one of the following: carbohydrates, agricultural or forestry by-products or wastes, such as straw, or particulate substrates, such as saw-dust, or wheat grains.

In use, the eco-friendly material filling may provide mechanical strength and/or insulation and/or sound-proofing and/or fire-resistant properties.

Preferably, the eco-friendly material filling being treated with flame-retardant chemicals or the like.

Further preferably, the eco-friendly material filling being used or admixed with blends or mixtures of other fill materials, or sandwiched or layered between other solid core materials.

Also according to the present invention there is provided an insulation panel for a door assembly, the insulation panel being formed from an eco-friendly material filling which comprises expandable cork or mycelium.

Further according to the present invention there is provided a method of forming a door assembly, the method comprising forming a door shell comprising a first panel and an opposite second panel, a first side member, a second side member, a top rail member and a bottom rail member, wherein the first panel, the second panel, the first side member, the second side member, the top rail member and the bottom rail member being arranged to form a void; and filling the void with an eco-friendly material filling.

It is believed that a door assembly and its method of manufacture in accordance with the present invention at least addresses the problems outlined above.

It will be obvious to those skilled in the art that variations of the present invention are possible and it is intended that the present invention may be used other than as specifically described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The present Invention will now be described by way of example only, and with reference to the accompanying drawings, in which: Figures la, lb and 1 c show side plan, exploded side perspective and side perspective views, respectively, of a door inner which forms the internal structure of the door assembly shown in Figure 3; Figures 2a, 2b and 2c illustrate side plan views of an industry-dimensioned standard insulation panel, and shows how the panel can be cut to provide material filling panels which completely fill the voids in the door inner of Figure 1; and Figures 3a, 3b, 3e and 3d show, for illustrative purposes only, side perspective views of the outer panelling that can be applied to the front and rear of the door inner of Figure 1 to provide different types of aesthetically-pleasing door assemblies.

DETIAILLD DESCRIP110N OF THE PRILFILRIW)E14BODIAILATIS The present invention has adopted the approach of providing internal and external door assemblies that utilise eco-friendly core materials to provide excellent mechanical strength, insulation and sound-proofing properties. Advantageously, the present invention also provides a method of manufacturing such door assemblies.

Referring now to the drawings, a door assembly 10 according to the present invention is illustrated in Figures 1 to 3. Specifically, the door assembly 10 is configured having panelling or outer skins 14, usually made of medium density fibreboard (MDF) or other engineered materials, sandwiched either side of a door inner or frame 12. Typically, the facings 14 can be decorative, as shown in Figure 3, allowing the door assembly 10 to mimic the appearance of a solid wood door.

Figures la, lb and lc show that the door frame 12 is formed as a largely-planar structure having longitudinal stiles or members 16a, 16b that are generally vertical segments located either side of the door frame 12. A series of lateral rails or members 18a, 18b, 18c, 18d are positioned between the longitudinal members 16a, 16b forming a ladder-like, rigid structure.

The skilled person will appreciate that the configuration best shown in Figure lb illustrates a door frame 12 which includes three cavities 20 positioned towards the top 20a, middle 20b and bottom 20c thereof, and into which a respectively-shaped insulating material filling panel 22a, 22b, 22c can be assembled within the cavities 20a, 20b, 20c. Although particular embodiments refer to a door assembly 10 having three material filling panels 22a, 22b, 22c formed within three cavities 20a, 20b, 20c, the skilled person will understand that this is in no way intended to be limiting as, in use, the present invention can be configured having any number of internal rails 18, and hence cavities 20.

Towards the middle of the door frame 12, and positioned generally equidistant between the top 18a and bottom rails 18d are lock stiles 24a, 24b which can receive latches and handles (not shown in Figure 3), as appropriate.

The skilled person will appreciate that the materials forming the door frame 12, such as the stiles 16, rails 18 and lock stiles 24, are solid wood. The door frame 12 can be screwed, joined, adhered or affixed together in any way as appropriate in the art.

Figure 2 shows how industry-dimensioned standard insulation panels 26 can be cut to provide the plurality of insulating material filling panels 22a, 22b, 22c that economically fit into the cavities 20a, 20b, 20c to minimise leftovers. In particular, Figure 2a shows that an industry-dimensioned standard insulation panel 26 can be cut to provide pieces IA and IB. Figure 2b shows that an industry-dimensioned standard insulation panel 26 can be cut to provide pieces 2A and 2B. Figure 2c shows an industry-dimensioned standard insulation panel 26 can be cut to provide pieces 3A, 3B, 3C and 3D. These pieces 1A, 1B, 2A, 2B, 3A, 3B, 3C and 3D are then placed inside the cavities 20a, 20b, 20c of the door inner 12, as perhaps best shown in Figure I a.

Figures 3a, 3b, 3c and 3d show, for illustrative purposes only, side perspective views of the panelling 14 that can be applied to the front and rear of the door frame 12 to provide an aesthetically-pleasing flush door assembly 10. The panels 14 can be laminated or adhered, as appropriate, to the frame 12. The panelling 14 can also include decorative grooves 28 and the like. In addition, in each of Figures 3a, 3b, 3c and 3d, the stiles 16a, 16b and the outermost rails 18a, 18d can be covered by a peripheral veneer or the like (not shown in Figure 3). The doors 10 shown him Figure 3 may, of course, require additional components including lips, locksets and final finishing, etc., as appropriate.

The panelling or outer skins 14 are formed from high density fibreboard (IMF), medium density fibreboard (MDF) or other engineered materials, and/or can include a GRP outer skin.

Whilst the door assembly 10 illustrated in the drawings is a standard interior panel faced door, this is in no way intended to be limiting as the present invention can be configured as a standard interior (including embossed doors, and panel faced), specialist interior and exterior (in particular fire-rated doors, capable of meeting 30-and 60-and I20-minute fire certification), and exterior GRP doors (which also includes fire-rated GRP doors).

Alternatively, or in addition thereto, the door assembly 10 may also include one or more glazing panels.

In one embodiment of the invention, the insulating material filling panels 22a, 22b, 22c can be formed from cork. In particular, a variant of cork, expandable cork. The skilled person will understand that cork is a natural, environmentally-friendly material. It is entirely biodegradable, and can be easily recycled Whilst a significant portion of harvested "virgin" cork is utilised for wine bottle corks, the insulating material filling panels 22a, 226, 22c described herein can be formed by expandable cork granules which are a by-product of the cork harvesting process.

To produce expandable cork panels 22a, 22b, 22c, the harvested cork granules are cleaned and placed in a mould, before being heated with steam for a period of time. After typically 15 to 20 minutes, the cork granules can expand by around 30%. The heat releases a natural resin in the cork that binds the expandable granules together in blocks. The cooled blocks can then be cut into different dimensions according to the end usage. No additional adhesives are therefore needed in the manufacture of the insulating material filling panels 22a, 22b, 22c as described herein.

In a further embodiment of the invention, the insulating material filling panels 22a, 22b, 22c are formed instead from mycelium. Such fungal-based bio-materials, or fungal composite materials, provide an excellent renewable and biodegradable alternative material to fossil-based resources. Materials of this type utilise natural fungal growth as a bio-fabrication method to convert by-products and waste streams into more sustainable synthetic construction materials.

The skilled person will understand that fungi are adept at converting raw by-products and waste inputs into a range of components and compositions. Fungi comprise a cell wall that is constantly extended at the tips of the hyphae, and mycelium being the mass of these branching hyphae. The present invention makes use of the fact that the structural cell wall of fungi can be a strong, hard substance. Whilst it is known in the prior art to culture fungi for food consumption, the present invention proposes to use the mycelium cellular structure as insulating material filling panels 22a, 22b, 22c in a door assembly 10. Such materials and composites, produced through the growth of fungi, can therefore be made efficiently, cost effectively and sustainably.

Mycelium, as described herein, can be produced using a low-energy, largely natural manufacturing process in which a nutrient material is required which can constitute any material that can sustain fungal growth, such as carbohydrates, agricultural or forestry byproducts or wastes, such as straw, or particulate substrates, such as saw-dust, or wheat grains. The above list is in no way intended to be limiting and exhaustive.

Irrespective of the type of nutrient feedstock material used, the substrates are firstly wetted with water to hydrate them. Moisture is critical to fungal growth, and the duration of this stage varies.

The hydrated nutrient material can then be sterilised to remove existing bacteria and fungi already present in the material, and then the nutrient material can be inoculated with a preselected fungus. Following inoculation, enclosures or moulds can be stored under ambient conditions, or a temperature-controlled environment, for a growth phase dependent on the fungal species and feedstock used, and the degree of mechanical bonding required.

After the growth phase, the composite materials can be removed from the enclosures or moulds, and dried to dehydrate the material and neutralise the fungus prior to shaping or cutting into a composite insulating material filling for a composite door assembly 10. Mycelium produced in this manner acts an insulating material with strong heat insulation and fire-resistant properties.

Both of these eco-friendly insulating fill materials are much more sustainable and environmentally-friendly to produce than conventional chipboard or cardboard.

It is also envisaged that the eco-friendly insulating fill materials described herein can also be used or admixed with blends or mixtures of other fill materials, or sandwiched or layered between other solid core materials.

Therefore, the door assembly 10 according to the present invention and its method of manufacture provides the necessary mechanical rigidity, insulation, and sound-proofing properties in an economical product, but one which also utilises a novel assembly of ecofriendly construction materials, and being more sustainable to produce.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components. The singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "includes" and/or "including" when used herein, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, separately, or in any combination of such features, can be utilised for realising the invention in diverse forms thereof.

The invention is not intended to be limited to the details of the embodiments described herein, which are described by way of example only. It will be understood that features described in relation to any particular embodiment can be featured in combination with other embodiments.

It is contemplated by the inventor that various substitutions, alterations, and modifications may be made to the invention without departing from the spirit and scope of the invention as defined by the claims. Examples of these include the following: As best shown in Figure 2, industry-dimensioned standard insulation panels 26 can be cut following a cut plan to form a plurality of' pieces IA, I B, 2A, 2B, 3A, 3B, 3C and 3D that have to be placed together inside cavities 20a, 20b, 20e. This is in no way intended to be limiting, as the present invention can be utilised with other cut plans aimed at economical manufacture and optimisation of cutting time and leftovers.

Whilst the present invention is primarily directed to three types of door assembly 10, namely standard interior (including embossed doors, and panel faced), specialist interior and exterior (in particular fire-rated doors, capable of meeting 30-and 60-minute fire certification), and exterior GRP doors (which also includes fire-rated GRP doors), this is in no way intended to be limiting as the present invention can be utilised with any number of door assemblies that can be produced in a more environmentally-friendly manner.

Claims

CLAIMS1. A door assembly, comprising: a door shell comprising a first panel and an opposite second panel, a first side member, a second side member, a top rail member and a bottom rail member, wherein the first panel, the second panel, the first side member, the second side member, the top rail member and the bottom rail member being arranged to form a void; and an eco-friendly material filling within the void.
2. The door assembly as claimed in claim 1, wherein the first and second panels being formed from high density fibreboard (IMF) or medium density fibreboard (MDF) or Glass Reinforced Polyester (GRP) or other engineered or natural materials.
3. The door assembly as claimed in claims 1 or 2, wherein the first and second panels being decorative enabling the door assembly to mimic the appearance of a solid wood door.
4. The door assembly as claimed in any of claims 1 to 3, wherein the first and second panels further comprise decorative grooves routed in the outer faces thereof and/or pressed or embossed decorative panels.
5. The door assembly as claimed in any of the preceding claims, further comprising a first lock stile which abuts against the first side member and a second lock stile which abuts against the second side member, and being positioned generally equidistant between the top rail member and the bottom rail member.
6. The door assembly as claimed in claim 5, further comprising one or more rail members interposed between the top rail member and the bottom rail member.
7. The door assembly as chimed in claim 6, further comprising two rail members interposed between the top rail member and the bottom rail member, and being arranged to form three voids in the door shell.
8. The door assembly as claimed in any of the preceding claims, wherein the side members, the rail members and the lock stiles being formed from solid wood.
9. The door assembly as claimed in any of the preceding claims, wherein the panels, the side members, the rail members and the lock stiles being screwed, joined, adhered or affixed together.
10. The door assembly as claimed in claim 1, wherein the outermost faces of the first side member, the second side member, the top rail member and the bottom rail member being covered by a veneer or receive a painted finish.
11. The door assembly as claimed in any of the preceding claims, wherein the door assembly being an interior wooden door, interior fire-rated door or exterior (GRP) composite door.
12. The door assembly as claimed in any of the preceding claims, further comprising one or more glazing panels.
13. The door assembly as claimed in claim I, wherein the eco-friendly material filling being expandable cork.
14. The door assembly as claimed in claim I, wherein the eco-friendly material filling being mycelium.
15. The door assembly as claimed in claim 14, wherein the eco-friendly material filling being obtainable from natural fungal growth which converts a nutrient feedstock into a sustainable synthetic construction material.
16. The door assembly as claimed in claim 15, wherein the nutrient feedstock is selected from the group consisting, but not limited to, any one of the following: carbohydrates, agricultural or forestry by-products or wastes, such as straw, or particulate substrates, such as saw-dust, or wheat grains.
17. The door assembly as claimed in claim 1, wherein the eco-friendly material filling providing mechanical strength and/or insulation and/or sound-proofing and/or fire-resistant properties.
18 The door assembly as claimed in claim 1, wherein the eco-friendly material filling being treated with flame-retardant chemicals or the like.
19. The door assembly as claimed in claim 1, wherein the eco-friendly material filling being used or admixed with blends or mixtures of other fill materials, or sandwiched or layered between other solid core materials
20. An insulation panel for a door assembly, the insulation panel being formed from an eco-friendly material filling which comprises expandable cork or mycelium.
21. A method of forming a door assembly, the method comprising: forming a door shell comprising a first panel and an opposite second panel, a first side member, a second side member, a top rail member and a bottom rail member, wherein the first panel, the second panel, the first side member, the second side member, the top rail member and the bottom rail member being arranged to form a void; and filling the void with an eco-friendly material filling.