GB2484914A

GB2484914A - A sheet metal door

Info

Publication number: GB2484914A
Application number: GB201017917A
Authority: GB
Inventors: David Eccleshall
Original assignee: INTERIORS Manufacturing Ltd
Current assignee: GATEWAY BIDCO LIMITED
Priority date: 2010-10-25
Filing date: 2010-10-25
Publication date: 2012-05-02
Also published as: GB201017917D0

Abstract

A door comprising 10 a first component 12 with a first door skin 16 and a second component 14 with a second, opposing skin 32, both skins formed at least partially from sheet metal, and a side wall structure 18a-d, 22a-d formed from the first and second components. The side wall structure has a plurality of integral resilient clip formations, the clip formations formed from a portion of the side wall structure of one of the components; and corresponding apertures 24 provided in the side wall structure of the other component. The clip may be a hook with barbs (40 Fig 9), the hook passing through a first aperture in the component and the barbs engaging with a second aperture following relative sliding motion of the components. Intumescent seals, sound seals or draught seals may be provided around the edge of the door and a fire retardant or sound insulating material provided between the first and second skins. A method of manufacture is also claimed.

Description

A Door The present invention relates to a door and to a method of assembly thereof More particularly, the present invention relates to a sheet metal door and a method of assembling such a door.

Sheet metal doors are known, but existing designs suffer from a number of disadvantages. In many instances, assembly of such doors requires a number of fabricating and welding operations that are time consuming and labour intensive to undertake, and often result in additional finishing work being required to make good the resulting heat and spatter damage.

Various proposals have been put forward for providing sheet steel doors that do not require welding. For example, FR27 13693 and W088/03983 both disclose doors in which the side faces include an integral resilient formation that enables the two door skins to be push fitted together. However, such designs may be problematic from a security perspective, and place unwanted restrictions on the door design.

U57478469 and GB2275493 disclose doors in which the two skins have interlocking formations that enable them to be slid parallel to their faces to interlock. However, such a formation may impose unwanted restrictions on the door design and assembly may be problematic because of the risk of the interlocking formations binding together due to friction during assembly. If however the formations are made sufficiently loose, problems with rattling and racking may then occur.

The present invention seeks to overcome or at least mitigate the problems of the prior art.

One aspect of the present invention provides a metallic door comprising: a first component including a first door skin at least partially formed from sheet metal; a second component including second, opposing skin formed at least partially from sheet metal; and a side wall structure formed from the first and second components; the side wall structure comprising: a plurality of integral resilient clip formations, the clips formations being formed from a portion of the side wall structure of one of the components; and corresponding apertures provided in the side wall structure of the other component of the door. This arrangement results in a secure door that is cost-effective and easy to manufacture.

The door preferably has clip formations arranged substantially parallel to the first or second skin. Alternatively, the clip formations are arranged at substantially 90° to the first or second skin. These arrangements provide for simple assembly using relatively unskilled personnel.

Preferably, the clip formations are provided in a clip flange and the apertures are preferably formed in an aperture panel of the side wall structure.

Advantageously the side wall structure comprises a side wall panel formed from the same sheet of material as the first skin or the second skin and folded through substantially 90°.

More preferably, the side wall structure comprises first and second side wall panels formed from the same sheets of material of the first skin and second skin respectively.

Preferably a side wall structures are provided on two opposing sides of the door, more preferably on four sides of the door. By providing structures on all four sides, no or limited additional steps may be needed to produce a finished door.

The door preferably comprises a recess in at least one side wall structure and an intumescent, sound or draught seal is even more preferably located in the recess.

The clip formations preferably comprise a hook formed integrally from the clip flange. This type of clip provides a secure connection and is simple to punch from the panel.

The apertures advantageously comprise for each clip formation a first aperture to receive the hook therethough and a second aperture against which a barb of the hook may engage following relative sliding motion of the first and second components.

The door may comprise an aperture for door hardware, such as a lockset or handle.

The door advantageously further comprises fire retardant and/or sound retardant material between the first and second skins.

A second aspect of the present invention provides a method of manufacturing a door according to a first aspect of the present invention comprising the steps of a) providing blanks for the first component and second component; b) forming the side wall structure from the blanks; and c) utilising the clip formations to attach the first component to the second component.

The method preferably further comprises a step of filling fire or sound retardant material within the door and/or the step of fitting door hardware, such as a lockset, handle or hinge to the door.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: FIGURES 1 and 2 are isometric views from opposing viewpoints of a door according to a first embodiment of the present invention in an exploded condition; FIGURE 3 is a cross-sectional view on a horizontal plane through one comer of the door of Figures 1 and 2 in an assembled condition; FIGURE 4 is an isometric view of the door of Figures 1 and 2 in an assembled condition; FIGURE 5 is an isometric view of a door according to a second embodiment of a second invention with internal components visible in phantom; FIGURE 6 is a similar view to Figure 5, but with a sectional view through an upper corner of the door; FIGURE 6A is an enlarged view of the section of Figure 6; FIGURE 7 is an isometric view of a door according to a third embodiment of the present invention; FIGURE 7A is an enlarged view of an upper corner of the door of Figure 7; FIGURE 8 is an isometric view of the upper corner of Figure 7 from a different viewpoint; and FIGURE 9 is an enlarged view of a clip formation suitable for in securing together the door components of all three embodiments.

With reference to Figures 1 and 2 it can be seen that a door indicated generally at 10 is formed from a first component 12 and a second component 14. The first component 12 comprises a first door skin 16 that is substantially planar and formed from a metal sheet, typically a steel sheet of a suitable grade of mild steel, typically having a thickness in the range of 1mm to 2mm. Dependent upon the intended usage environment of the door, the metal may be galvanised, coated with plastics (e.g. a wood effect foil), painted, or in harsh environments, stainless steel may be used.

The first component additionally comprises four side panels 1 8a to 1 8d, which are provided at substantially 90° to form an enclosed box structure. Edges of the adjacent side panels 18a to 18d meet at a corner joint 20. Four connecting flanges 22a, 22b, 22c and 22d extend at 90° to their corresponding side panels in an inboard direction, such that the connecting flanges are parallel to and spaced from the first door skin 16.

Each of the connecting flanges are trapezoidal in shape so that the corner joints 20 extend inboard between adjacent connecting flanges (e.g. 22a and 22b).

Each connecting flange 22a to 22d is provided with at least one connecting aperture formation indicated generally at 24. In this embodiment each connecting aperture formation comprises a relatively large rectangular aperture 26 and a smaller aperture aligned therewith but separated therefrom by a connecting bridge of metal 30.

With reference to the intended orientation of the door 10 in use, in this embodiment the larger aperture 26 provided directly above the smaller aperture 28. In other embodiments the orientation may be adjusted so the large aperture is below or to the side. The longer upright connecting flanges 22a and 22c are provided with five equidistantly spaced connecting aperture formations 24. The shorter transverse connecting flanges 22b and 22d are provided with two connecting aperture formations 24 each. In other embodiments the position and number of connecting aperture formations may be adjusted as needed.

With particular reference to Figure 2, the second component 14 comprises a second door skin 32 having substantially the same dimensions as the first skin 16. The second skin 32 is formed from similar material to the first 16. Trapezoidal clip flanges 34a, 34b, 34c and 34d of a similar shape to the connecting flanges 22a, 22b, 22c and 22d are folded through substantially 180° so as to overlie the second skin 32 in a face contacting relationship.

A plurality of clip formations 36 are positioned on each of the clip flanges on the interior side of the panels. Each clip formation 36, shown in detail in Figure 9, comprises a hook 38 punched from the flanges 34a to 34d to leave a hole 39 in the panel. The open end of each hook 38 is directed downwardly. A central barb 40 extends from each hook 38 upwardly and towards the flange 34a to 34d from which it is formed. As can be seen from the figures, the hooks are relatively small in relation to the overall dimensions of the door. For example, each hook may be of the order 10mm wide and 20mm long, although may vary in other embodiments e.g. up to 50mm in length and 20mm in width. Punches to produce clip formations of this type

S

are supplied by e.g. Mate Tooling Solutions of Northampton, UK. The clip formations 36 are aligned with corresponding connecting aperture formations 24.

To assemble the second component 14 to the first component 12, the hooks 38 are S inserted through the large aperture 26 such that the clip flanges 34a to 34d are in a face contacting relationship with the corresponding connecting flanges 22a to 22d, but there is a slight vertical offset between the two (generally less than 50mm, but typically 10-15mm). The second component 14 is then slid downwardly with respect to the first component 12, this causes the hooks 38 to deflect and ride over the connecting bridge 30 in a resilient manner, and the barb 40 to then spring back and engage against an edge of the smaller aperture 28. This inhibits the second component 14 being slid back in the opposite direction to disengage the two components 12, 14. The hook 38 is suitably dimensioned to resiliently urge the first and second components into a close contacting relationship where the risk of rattles and racking occurring is minimised. It will be further appreciated that because of the minimal sliding required for the bars 40b to engage the small aperture 28, problems with binding are minimised.

Panels/flanges 1 8a to d, 22a to d and 34a to d together define a side wall structure 25.

(See Figures 3 and 4).

Figure 3 illustrates the connection between the first and second components when viewed from above. The hook 38 can be seen overlying the connecting flange 22a.

Of particular note in Figure 3 is the fact that the join 45 along the edge between the second skin 32 and the side walls 18 is rounded and does not require any further operations to give a smooth comer transition.

Fabrication of the door 10 is preferably carried out by a stamping and bending operation. Blanks for the first component 12 and second component 14 are first cut from sheet steel. The steel may be pre-finished with paint, galvanising or another coating. Simultaneously or subsequently, the connecting aperture formations 24 and clip formations 36 are formed in the respective components. At this stage, additional apertures (not shown) may be provided for the fitting of locksets, handles, windows and other accessories.

A bending operation is then carried out to arrive at the first and second component shapes 12 and 14 illustrated in Figure 1 and 2. The handles, locksets and other accessories may then be fitted to the first and second components as appropriate, sound and/or fire insulation material positioned within the space provided by the first skin 16, side panels 1 8a to d and connecting flanges 22a to d. The first and second components may then be fitted together as described above in order to complete the door assembly and produce a door as illustrated in Figure 4.

It will therefore be appreciated that the assembly process is very simple, and may be undertaken using largely unskilled labour. The requirement for finishing operations is removed or minimised. Once assembled, access to the clip formations 36 is restricted, meaning that the door is not easily disassembled, thereby enhancing its security.

With reference to Figure 5 a door 110 according to a second embodiment of the present invention is illustrated. Like parts are labelled with similar numerals, but with the addition of the prefix "1". Only those parts that differ from the first embodiment are discussed in detail.

The door of this embodiment differs from that of Figures 1 to 4 in that the second component 114 is provided with side panels 142a, b, e and d intermediate the second door skin 132 and the clip flanges 134a to d. It can be seen that the panels 142a to d are shallower than the corresponding side panels 11 8a to d of the first component.

This embodiment has a number of advantages over that of the Figures 1 to 4. Tn certain instances, a sound and/or fire insulating board or fibres can be fitted into the area defined by these panels, and the depth of side panels 142a to d may be controlled so as to match the thickness of the material to be received.

In addition, by having an overall side wall structure 125 formed from adjacent side panels 118a to d and 142a to d of both components, the joint between the first and second components is moved towards the centre of the side wall structure. Therefore, when the door is closed and located within a door frame (not shown), access to the join 145 between the panels 118a to d and 142a to d is inaccessible, reducing the risk that an attacker may be able insert a crowbar into the join 145 in order to separate the two components as a way of gaining unauthorised access to an area closed off by the S door 110.

Finally, in circumstances where doors of differing overall depth may be needed, the first component 112 may always be manufactured with standard dimensions, including a standard depth, and the second component may be adjusted to provide side panels 142a to d of varying depths to achieve the total overall desired thickness of the door. This may reduce the complexity of manufacture, and reduce levels of stock required.

Figures 7, 7A and 8 illustrate a door 210 according to a third embodiment of the present invention. This embodiment has a differing side wall structure compared to the first two embodiments. Like parts are labelled by like numerals, but with the addition of the prefix "2".

Specifically, in this embodiment, the side panels of the first and second components are adjusted so that the connecting flanges 222a and c of the first component are now in the plane of the corresponding side wall panels 218a and c. The clip flanges 234a and c are also arranged in this plane, such that the clip formations project inboard to the centre of the door on one side and outboard, away from the centre of the door on the other side.

Additionally, each of the components is provided with recess panel 245a and 245c and 246a and 246c that extend inboard in a spaced parallel relationship in order to provide a trough or recess in the side wall structure 225. This recess may be used to locate an intumescent seal 252 or the like to enhance the door's 210 fire rating or a draught seal to enhance its insulating properties. The hooks 238 continue to extend downwardly and the two components 210 and 212 are brought together such that the hooks are introduced through the large apertures (not visible) and the second component 212 slid downwardly with respect to the first 210 for the clip formations 236 to secure the components together.

In this embodiment, because of the change in orientation of the clip formations 136, it is not also possible to clip together the upper and lower side walls. As such, upper and lower end caps (not shown) may be fitted, preferably again with recesses that correspond to those on the side walls to close off the upper and lower openings. The caps also impart rigidity and strength to the door 210.

Again, manufacture of the door is achieved by a stamping operation, followed by a folding operation, and then the clipping together of the first and second components, and then with the closing off of the top and the bottom. Additional openings (not shown) may be provided to fit additional hardware and accessories to the door.

It can be seen that all of the embodiments described above provide for a secure, low cost, and easy to assemble door that may easily incorporate fire and sound retardant material, and have door hardware such as locks handles and hinges easily fitted thereto. The assembly process means that the sheet metal used may be provided with suitable finishes such as plastic coatings or paint prior to the stamping and folding operation so that final finishing operations may not be needed.

It will be further appreciated that numerous changes may be made within the scope of the present invention. For example, different side wall profiles may be used, the door skins may be embossed with relief patterns that imitate traditional wooden door constructions and the like, windows may be provided within the door structure with the window surrounds being formed at least partially from folded sections of the door skins. Similar construction methods may be employed in other applications, such as ceiling and floor hatches and different materials may be used as required, such as aluminium. Differing materials may be used for the two components. The clip formations may be provided on the first component and apertures on the second.

Suitable alternative clip and aperture formations may be used.

Claims

Ctaims 1. A door comprising: a first component including a first door skin at least partially formed from sheet metal; a second component including second, opposing skin formed at least partially from sheet metal; and a side wall structure formed from the first and second components; the side wall structure comprising: a plurality of integral resilient clip formations, the clips formations being formed from a portion of the side wall structure of one of the components; and corresponding apertures provided in the side wall structure of the other component of the door.
2. A door according to Claim 1 wherein the clip formations are arranged substantially parallel to the first or second skin.
3. A door according to Claim 1 wherein the clip formations are arranged at substantially 90° to the first or second skin.
4. A door according to any preceding claim wherein the clip formations are provided in a clip flange.
5. A door according to any preceding claim wherein the apertures are formed in an aperture panel of the side wall structure.
6. A door according to any preceding claim wherein the side wall structure comprises a side wall panel formed from the same sheet of material as the first skin or the second skin and folded through substantially 90°.
7. A door according to claim 6 wherein the side wall structure comprises first and second side wall panels formed from the same sheets of material of the first skin and second skin respectively.
8. A door according to any preceding claim comprising a side wall structure on two opposing sides of the door.
9. A door according to Claim 8 comprising a side wall structure on four sides of the door.
10. A door according to any preceding claim comprising a recess in at least one side wall structure.
11. A door according to Claim 10 further comprising an intumescent, sound or draught seal located in the recess.
12. A door according to any one of claims 4 to 11 wherein the clip formations comprise a hook formed integrally from the clip flange.
13. A door according to preceding Claim 12 wherein the apertures comprise for each clip formation a first aperture to receive the hook therethough and a second aperture against which a barb of the hook may engage following relative sliding motion of the first and second components.
14. A door according to any preceding claim further comprising an aperture for door hardware, such as a lockset or handle.
15. A door according to any preceding claim further comprising fire retardant and/or sound retardant material between the first and second skins.
16. A method of manufacturing a door according to any preceding claim comprising the steps of: a) providing blanks for the first component and second component; b) forming the side wall structure from the blanks; and c) utilising the clip formations to attach the first component to the second component.
17. A method according to claim 16 further comprising a step of fitting fire or sound retardant material within the door.
18. A method according to claim 16 or claim 17 further comprising the step of fitting door hardware, such as a lockset, handle or hinge to the door.
19. A door or method substantially as hereinbefore described and/or with reference to Figures 1, 2, 3, 4, 5, 6, 6A, 7, 7A, 8 or 9 of the drawings.