GB2264522A

GB2264522A - A door and method of producing a door

Info

Publication number: GB2264522A
Application number: GB9202317A
Authority: GB
Inventors: Phillip Samuel Checkett; Gerald Birch
Original assignee: P V C PRODUCTS Ltd
Current assignee: P V C PRODUCTS Ltd
Priority date: 1992-02-04
Filing date: 1992-02-04
Publication date: 1993-09-01
Also published as: GB9202317D0

Abstract

A door suitable for use as an internal door in a building comprises frame structure having opposed top and bottom rails (18 and 20) and opposed stiles (22 and 24). Opposed plastics covering sheets (12 and 14) are secured such as by an adhesive to the frame structure and the internal voids are filled with foam plastics slabs (18). At least one of the rails and stiles is formed of a readily machinable material e.g. fibreboard whereby the door may be machined to a required size by the user. Cover strips 34 and 36 are secured to the stiles to complete the door. <IMAGE>

Description

Title: A door and method of producing a door This invention relates to a door and to a method of producing a door.

There are many known types of door construction and, conventionally, interior wooden doors have been constructed either of solid wood or as a wood frame with wood skins whereas exterior doors have generally been constructed of solid wood. It is also known to produce exterior doors of plastics materials comprising a plastics, e.g. UPVC, skin bonded on each side to an infill panel of a plastics foam, e.g. polystyrene, with such skinned infill being secured within a finished frame of a plastics material e.g. UPVC. Such doors have not been usable either as new or replacement doors for existing wooden frames because, as will be well known to those in the building trades, doors generally require adjustment and finishing in situ to fit snugly into their frames.Thus the known finished plastics exterior doors have generally been provided as ex-factory units with purpose-designed plastics frames, the doors being provided with factory fitted hinges, locks and any other door furniture.

Known interior doors have comprised a wooden frame structure with a thin wooden skin secured to each side of the frame structure. The frame structure in known manner has comprised top and bottom horizontal rails and horizontally spaced apart vertically extending stiles. For purposes of rigidity there has also generally been provided a further vertically extending centrally positioned mullion together with a further horizontally extending rail for the purposes of accommodating lock structure and providing sufficient rigidity for such structure to be secured to the door. Infill material, often comprising no more than corrugated cardboard, has been provided within the door voids defined between the opposed inner faces of the wooden skins and the respective inner edges of the rails and stiles.Such a skin construction of interior door therefore enables the user to finish the door in situ to fit snugly into an existing door frame, the outside edges of the top rail and/or the bottom rail and/or the two stiles generally being finished by planing. Such doors are usually purchased by the user without pre fitted hinges, locks or any other door furniture, these items being fitted by the user when the door is fitted to its frame.

Such skin constructions of doors are not generally suitable for exterior use as they lack the necessary rigidity for security purposes and are not weather resistant. Hence, for exterior purposes, either solid wooden doors have been utilised or the above mentioned constructions of plastics door pre-fitted in a plastics frame.

It is an object of the present invention to provide a door having the advantages of a plastics finish to its front and rear surfaces but which is finishable in situ whereby it may be fitted into an existing door frame. A further object of the invention is to provide a method of producing such a door.

In accordance with one aspect of the invention there is provided a door comprising a frame structure having a top rail, a bottom rail, and spaced stiles extending between said rails, at least one of each of said rails and stiles being formed of a material which is machinable such as by planing whereby the overall dimensions of the frame structure may be readily adjusted; front and rear surface coverings overlying said frame structure and secured thereto, each said covering comprising a sheet of plastics material, and infill material situate in the voids between the opposed inner faces of said surface coverings and the inner edges of the rails and stiles.

Also in accordance with the invention there is provided a method of producing a door comprising the steps of positioning a first plastics covering sheet on a positioning member, positioning a frame structure on the inner face of said covering sheet, said structure comprising top and bottom rails and stiles, at least one of each of said rails and stiles being formed of a readily machinable material, positioning infill material in the voids bounded by said rails and stiles and the inner face of said first covering sheet, and positioning a second plastics covering sheet over the frame structure; the method including the applying of adhesive materials to some at least of the respective mutually contacting surfaces of the covering sheets, frame structure, and infill material during the assembly process.

Such a door has the advantage of having plastics coverings to its front and rear faces whilst also being finshable in situ to fit an existing door frame.

The plastics covering sheets are easily cleanable and have the further advantages of providing better impact and general wear resistance than the conventional wooden skins. The plastics covering sheets are preferably provided with fire retardant properties, and the infill material which conveniently comprises slabs of foam plastics is also conveniently provided with fire retardant properties.

Each of the plastics covering sheets is conveniently coextensive with the frame structure so that, during the assembly operation, each edge of each sheet extends to a corresponding edge of the frame structure. During any subsequent finishing operation on the door, e.g. by planing one or more of the rails or stiles, the associated edges of the covering sheets can be planed at the same time. All of the rails and stiles of the frame structure are conveniently formed of the same readily machinable material which may comprise a fibreboard material.

The door is preferably provided with cover strips detachably securable to the edges of the two stiles. Each stile is conveniently provided with a longitudinally extending groove within which is engageable a gripping member of a cover strip.

Conveniently each cover strip comprises a plastics extrusion having a said gripping member engageable in said groove, a web portion adapted to overlie the edge of a stile and two spaced apart flanges each adapted to overlie the outer surface of a said covering sheet of the door.

That cover strip which is adapted to be fitted to the free edge stile of the door is conveniently provided with an aperture for the reception of a protruding bolt or catch of lock mechanism fitted to the door.

That cover strip which is adapted to be fitted to the hinge edge stile of the door is conveniently provided with a continuous step, which may include a groove, affording a rebate to receive one or more hinge plates at any position therealong.

Each of said plastics covering sheets may conveniently be formed by a vacuum moulding technique to provide decorative design features on said sheet.

Said design features may include one or more relief areas extending outwardly of the plane of the sheet thereby providing a void behind said area and preferably each said void is packed with filler material.

The door may include smoke detecting and alarm means. A smoke detector and alarm may be received within a recess in a rail or stile of the door, conveniently in the top rail, with the recess being in communication such as by one or more bores with an interior void of the door. One or both of the plastics covering sheets may be provided with apertures affording a smoke ingress to the said interior void in the door and hence to the smoke detector and alarm.

Other features of the invention will become apparent from the following description given herein solely by way of example with reference to the accompanying drawings wherein: Figure 1 is a front elevation of a door constructed in accordance with the invention but omitting the front plastics covering sheet and the two stile edge cover strips; Figure 2 is an end view taken in the direction of arrow II of Figure 1 but including both plastics covering sheets; Figure 3 is a transverse cross-sectional view taken on the line rn-rn of Figure 1 and including both plastics covering sheets; Figure 4 is a transverse cross-sectional view on the line IV-W and showing also the stile edge cover strip at the free edge of the door; ; Figure 5 is a transverse cross-sectional view on the line V-V of Figure 1 and showing the stile edge cover strip at the hinge edge of the door; and Figure 6 is a partially cut-away scrap view of a top corner of the door showing the installation of a smoke alarm.

A door constructed in accordance with the invention consists essentially of a frame structure 10, opposed front and rear plastics covering sheets 12 and 14 overlying the frame structure, and infill material 16 located between the opposed inner faces of the plastics covering sheets 12 and 14. The frame structure comprises top and bottom rails 18, 20 interconnected by spaced stiles 22,24 and the frame structure may include, as shown in the accompanying drawings, a central mullion 26 and additional horizontal rails 28. The outer edge of each stile 22 and 24 is provided with a continuous respective groove 30, 32 along its full length to a depth of approximately 15mm for a purpose which will be described in more detail below.

As will be clearly seen from Figures 1 to 3, each void bounded by the opposed inner faces of the covering sheets 12 and 14 and the respective edges of the rails, stile and mullion is packed with an infill material 16 which conveniently comprises a slab of polystyrene or other plastics foam material having fire retardant properties. Each of the plastics covering sheets 12 and 14 may conveniently be vacuum moulded to provide, as shown in the drawings, a relief design feature and the internal void in the door provided by such features may also conveniently be packed with infill plastics foam material.

To assemble the door shown in Figures 1 to 3 a first covering sheet of plastics material, e.g. the rear sheet 14, is positioned horizontally in a jig. The plastics covering sheet 14 is conveniently formed as a vacuum moulding with whatever design features are required with the overall dimensions of the sheet being to standard rectangular dimensions to enable the finished door to be fitted to a standard size wooden door frame. A frame structure 10 is then positioned horizontally on said first covering sheet 14. Such frame structure comprises the top and bottom rails 18, 20, the pair of opposed stiles 22, 24 interconnecting the top and bottom rails and conveniently, as shown in Figure 1, a central mullion 26 interconnecting the top and bottom rails and additional rails 28 extending between a respective stile and the mullion.Such a frame structure 10 is produced as a pre-assembly with the various members thereof being secured together such as by known corrugate metal crimps. The overall rectangular dimensions of the frame structure 10 are co-extensive with the rectangular dimensions of the first plastics covering sheet 14. At least one of the rails 18, 20 and at least one of the stiles 22,24 is formed of a material which is readily machinable such as by planing and, conveniently, all of the members of the frame structure 10 are formed of a readily machinable material such as fibre board.

Either or both of the respective contacting faces comprising the inner face of the first plastics covering sheet 14 and the adjacent faces of the rails, stiles and mullion are coated with an adhesive material before the frame structure 10 is positioned on the inner face of the first covering sheet 14.

The aforesaid slabs of inlll material 16 are then positioned within the respective voids bounded by the inner face of the first covering sheet 14 and the adjacent edges of the rails 18, 20, 28, the stiles 22, 24 and the mullion 26. Such infill slabs are also conveniently secured in position by an adhesive which may be applied to either or both of the respective contacting surfaces of the slabs and the covering sheet before the slabs are positioned in the voids.

Finally, a second plastics covering sheet i.e. the front sheet 12, which may be identical in shape and configuration to that of the first sheet 14 is positioned on the frame structure 10 and secured thereto by an adhesive applied to one or more of the respective contacting surfaces of the second cover sheet and the frame structure. If the plastics covering sheets 12 and 14 are provided with the relief design features of the type shown in the drawings, then the additional internal voids provided by such features may also be filled by appropriately shaped plastics foam packing material adhesively secured in position within said voids during the assembly process.

Thus the door produced by the process described above is as shown in Figures 1 to 3 wherein each of the plastics covering sheets 12 and 14 is coextensive with the fibre board frame structure 10. Such a door is readily finishable by the user in situ to enable the door to fit snugly to an existing door frame. If both top and bottom rails 18 and 20 and both stiles 22 and 24 of the frame structure are formed of a readily machinable material such as fibre board then any one of these members may be readily planed by the user to enable the door to fit snugly to its frame. During the planing operation the co-extensive edges of the front and rear plastics covering sheets 12 and 14 can also be planed down flush with the respective rail or stile edge as the case may be.

After the door has been finished to size, the exterior edges of the stiles 22 and 24 are finished by the securing thereto of respective cover strips 34 and 36.

The free edge of the door is as shown in Figure 4 wherein a cover strip 34 comprises a plastics extrusion having a central "christmas tree" serrated gripper member 38 for engaging within the groove 30 in the exterior edge of the stile 22.

The cover strip 34 includes web 40 and a pair of opposed flange members 42, 44 extending from the web 40 in the same direction as the gripper member 38 whereby, when the cover strip is assembled to the stile 22 as shown in Figure 4, the web 40 overlies the outer edge of the stile 22 and the flanges 42, 44 overlie respective adjacent outer faces of the plastics covering sheets 12 and 14 of the door.

The free edge cover strip 34 illustrated in Figure 4 is conveniently formed with a pre-cut rectangular aperture (not illustrated) in its web 40 to be positioned adjacent the centre rail 28 of the door whereby lock and catch mechanism subsequently secured to the centre rail 28 may be provided with the latch bolt protruding outwardly of the cover strip 34 through the said aperture.

A somewhat similar cover strip 36 is applied to the hinge stile 24 of the door as shown in Figure 5. This cover strip also comprises a plastics extrusion having a gripper member 46 but is shaped to include a continuous rebate groove defined between a web portion 50 of the cover strip adjacent the stile edge and a further web portion 52 of the cover strip spaced outwardly away from said first web portion 50. This construction enables a hinge plate 54 to be secured to the stile edge by means of screws extending through the hinge plate and through the first web portion 50 of the cover strip into the stile with the hinge plate itself being partially received within the rebate groove 48. Thus there is no need for the user to cut a rebate into the stile itself.The cover strip 36 includes a pair of opposed flange members 56 and 58 each extending respectively from a web portion 50 and 52 in the same direction as the gripper member 46 whereby, when the cover strip is assembled to the stile 24 as shown in Figure 5, the web portions 50, 52 overlie the outer edge of the stile 24 and the flanges 56, 58 overlie respective adjacent outer faces of the covering sheets 12 and 14.

In Figure 6 of the drawings there is shown the optional provision of a smoke detector and alarm which, in the example illustrated, comprises a battery powered unit 60 located within a recess 62 formed in the top rail 18 of the door frame structure 10. Bores 64 extend from the lower face of the recess 62 into a door void immediately below the top rail 18. Smoke ingress apertures 66 are formed as illustrated in the front plastics covering sheet 12 of the door and, as will be appreciated, similar smoke ingress apertures may be provided in the rear covering sheet 14 of the door. Thus any smoke adjacent the door can enter the interior voids of the door to activate the smoke alarm.

Thus a door constructed in accordance with the invention possesses the advantages normally attributable to a plastics finish door in that the plastics covering sheets 12 and 14 of the door have a high impact and wear resistance and are readily cleanable and can be formed of a fire retardant material. The infill material 16 can also be provided as a fire retardant At the same time, the door can be readily finished in situ by the user to enable it to fit to an existing door frame. The finished door is then neatly trimmed by the fitting of the cover strips 34 and 36, the cover strip 36 providing a particular advantage in enabling the fitting of hinges at any position therealong without any need to cut into the hinge stile 24.

The features disclosed in the foregoing description, 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, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A door comprising a frame structure having a top rail, a bottom rail, and spaced stiles extending between said rails, at least one of each of said rails and stiles being formed of a material which is machinable such as by planing whereby the overall dimensions of the frame structure may be readily adjusted; front and rear surface coverings overlying said frame structure and secured thereto, each said covering comprising a sheet of plastics material, and infill material situate in the voids between the opposed inner faces of said covering sheets and the inner edges of the rails and stiles.

2. A door as claimed in claim 1 wherein a cover strip is securable to overlie the outer face of each said door stile.

3. A door as claimed in claim 2 wherein that cover strip which is securable to the, in use, free edge of the door includes a pre-formed opening therein to accommodate a lock or latch mechanism mounted on the door.

4. A door as claimed in either one of claims 2 or 3 wherein that cover strip which is securable to the, in use, hinge edge of the door includes a continuous longitudinally extending rebate to accommodate the mounting of hinge plates to the cover strip.

5. A door as claimed in claim 4 wherein said cover strip rebate includes a co-extensive longitudinally extending groove to accommodate the hinge plates of hinges mounted to the cover strip.

6. A door as claimed in any one of claims 2 to 5 wherein each said cover strip is co-extensive with the respective door stile to which it is securable.

7. A door as claimed in any one of claims 2 to 6 wherein each said cover strip includes a web portion adapted to be positioned against the outer face of the respective door stile to which it is securable, and opposed flange portions each adapted to be positioned against the adjacent outer face of a respective covering sheet.

8. A door as claimed in any one of claims 2 to 7 wherein each said cover strip is formed as a plastics extrusion.

9. A door as claimed in any one of claims 2 to 8 wherein each said cover strip includes a gripping member engageable in a longitudinally extending groove in the respective door style.

10. A door as claimed in any one of the preceding claims wherein each said covering sheet comprises a vacuum moulded sheet of plastics material.

11. A door as claimed in claim 10 wherein the or each said covering sheet includes decorative features formed on the outer face of the sheet.

12. A door as claimed in any one of the preceding claims wherein said covering sheets are formed of a material having high impact strength and wear resistance.

13. A door as claimed in any one of the preceding claims wherein at least said at least one of each of said rails and stiles of said frame structure are formed of a fibreboard material.

14. A door as claimed in claim 13 wherein all of said rails and styles of said frame structure are formed of a fibreboard material.

15. A door as claimed in any one of the preceding claims wherein adjacent respective rails and stiles of said frame structure are secured to one another by a mechanical connection.

16. A door as claimed in any one of the preceding claims wherein the said covering sheets have fire retardant properties.

17. A door as claimed in any one of the preceding claims wherein said infill material comprises a foam plastics material.

18. A door as claimed in any one of the preceding claims wherein said infill material comprises foam plastics material in slab form.

19. A door as claimed in any one of the preceding claims wherein said infill material has fire retardant properties.

20. A door as claimed in any one of the preceding claims wherein smoke detection means is mounted in the door.

21. A door as claimed in claim 20 wherein said smoke detection means is mounted in a said rail or stile of the door in communication with a void between the opposed inner faces of the covering sheets, smoke ingress means in the door permitting communication of said void with atmosphere whereby smoke in the atmosphere may be detected by said detection means.

22. A method of producing a door comprising the steps of positioning a first plastics covering sheet on a positioning member, positioning a frame structure on the inner face of said covering sheet, said structure comprising top and bottom rails and stiles, at least one of each of said rails and stiles being formed of a readily machinable material, positioning infill material in the voids bounded by said rails and stiles and the inner face of said first covering sheet, and positioning a second plastics covering sheet over the frame structure; the method including the applying of adhesive materials to some at least of the respective mutually contacting surfaces of the covering sheets, frame structure, and infill material during the assembly process.

23. A method according to claim 22 including the finishing steps of planing one or more of said rails or stiles and the adjacent edge of the or each respective covering sheet to a size required by the user.

24. A method according to either one of claims 22 or 23 including fitting a pre-formed cover strip to overlie the outer face of each said door stile.

25. A method according to any one of claims 22 to 24 including forming said frame structure as a pre-assembly of rails and stiles before it is positioned on said first covering sheet.

26. A method according to claim 25 including the steps of securing adjacent respective rails and styles together by mechanical connections to form said pre-assembly.

27. A method according to any one of claims 22 to 26 including the steps of forming said plastics covering sheets to shape by a vacuum moulding process.

28. A method of producing a door substantially as hereinbefore described with reference to the accompanying drawings.

29. A door constructed and arranged substantially as hereinbefore described with reference to the accompanying drawings.

30. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.