GB2121855A - Roller shutters - Google Patents

Abstract

A thermally insulated roller shutter comprises a transversely corrugated longitudinally flexible panel structure (10) e.g. of flexible sheet metal, with flexible insulation material attached to the crests of the corrugations (11) on the inner side. The panel preferably comprises a first layer (12) of a resilient foamed plastics which will compress to minimal thickness when the shutter is coiled and which bridges the valleys between the corrugations when it is extended, and a facing (13) of a flexible heat-reflective foil or film. <IMAGE>

Description

SPECIFICATION Roller shutters This invention relates to roller shutters, particularly but not exclusively vertically opening roller doors as used for factories, workshops, commercial garages and the like, said doors normally being power operated for speedy and convenient closure of large wall openings but it is contemplated that the invention may have application to other forms of roller shutters serving as closures or screens e.g. of processing or storage chambers or possibly on vehicles, boats or transport containers.

Ever rising energy costs and the need to conserve natural fuels has led to increasing emphasis on prevention of heat loss and the effective insulation of buildings, often enforced by legal requirements laying down minimum standards. There is also increasing emphasis on maintenance of a satisfactory and comfortable working environment with maintenance of acceptable temperature ranges within the building. While roller shutters and doors have been produced for many years their thermal (and acoustic) insulation properties are poor as, by their nature, the shutters are normally constructed from a single thickness of sheet metal formed in laths or panels, in many cases articulated by pivot or hinge joints making the incorporation of insulation of any durability difficult or impossible.In particular the coiling mechanism of the shutter and the space available to accommodate it when coiled cannot usually be conveniently altered e.g. to accommodate thicker panels or laths.

Heat losses through the conventional type of sheet metal roller shutter are substantial both by thermal transmission through the material of the shutter and due to inefficient sealing permitting passage of draughts through any hinge joints and round the edges of the shutter where it slides in guides.

The object of the invention is the provision of a roller shutter of simple and durable construction and operation and provided with effective thermal insulation.

The invention provides a roller shutter comprising a longitudinally flexible panel structure capable of being unrolled and rolled for extension and retraction from a coiled condition and having a series of transverse ribs or corrugations parallel to the axis of rolling whose crests lie inwardly of other portions of the panel; and a flexible sheet of insulating material attached at least to said crests on the inner side of the panel to be unrolled and rolled therewith.

Preferably the panel structure is an effectively continuous metal sheet having no hinge joints formed to provide transverse corrugations and itself sufficiently flexible to be rolled into the coiled condition, and the insulating material is attached, e.g. bonded by an adhesive, to the crests only of said corrugations so that it bridges valleys defined therebetween on the inner side when the shutter is uncoiled.

Said insulating material may include a layer of resilient foamed plastics material and/or a skin of heat-reflective materials such as metallised plastics film or metal foil, and/or a composite sheet formed from a plurality of such materials.

It is also preferred that the lateral edges of the panel structure are provided with sealing strips and further insulation filling the ends of outer valleys, e.g. those defined by the outside of said corrugations, to provide effective sealing of the shutter in relation to its guide formations in use.

While insulation to prevent heat loss from a space operatively enclosed by the shutter in use is the primary consideration it will be appreciated that use of the invention will also reduce unwanted heating of the space from outside e.g. a building whose roller doors are exposed to summer sun or requiring a closely temperature controlled environment and also, particularly if foamed insulating material is employed, reduction of transmission of noise through the shutter.

One practical embodiment of the invention is now more particularly described with reference to the accompanying drawings wherein:~ Figure 1 is a cut-away perspective view of a rear portion of a roller shutter in an extended condition and with an associated guide formation; and Figure 2 is a perspective view of a lateral edge portion of the front of said shutter.

The shutter comprises a panel structure 10 of sheet metal e.g. galvanized or plastics coated mild steel 0.50 mm thick. The sheet is formed to have a series of integral corrugations 11 pitched, in this example, at intervals of some 80 mm and being some 20 mm in depth inwardly of the general plane of the structure. Corrugations 1 1 extend laterally the full width of the shutter.Depending on the required length the structure may be built up from a series of panels joined by transverse locked seams additionally secured by rivetting but the entire structure is in effect a single sheet and, while having sufficient lateral stiffness to form an effective closure, is sufficiently flexible longitudinally for it to be unrolled and rolled for extension and retraction, e.g. lowering and raising in the door opening of a building, from a coiled condition, conveniently by electrically powered operating gear (not shown) of conventional design.

The inner side of the shutter further includes thermal insulation comprising a first layer being a sheet 12 (Figure 1) of resilient foamed polyurethane plastics of a flame retardant composition some 25 mm thick. Sheet 12 is generally planar with the shutter extended and is attached to the crests only of corrugations 11 by means of a flame retardant contact adhesive.

The face of sheet 12 remote from structure 10 has a tough flexible aluminised polyester film 1 3 bonded to it so forming a composite insulation combining heat reflective and low heat conductivity properties.

This insulation is carried on the inner side of the structure i.e. the side which will normally face inwardly of a building or other space and the side which will face radially inwardly of the coil formed when the shutter is rolled up.

When extended, as shown in Figure 1 , this insulation bridges the valleys defined between corrugations 11 on said inner side and the still air trapped in said valleys adds to the insulating effect.

When formed into a coil the foamed sheet 12 will compress to a minimal thickness on the corrugation crests and can fold itself into said valleys along with the film 13 so that the shutter can be coiled to the same radius as the equivalent uninsulated shutter without damage to the insulation or affecting the shutter flexibility. When unrolled again the foam sheet 12 springs resiliently back to its undistorted condition and film 13 is extended without permanent damage.

Lateral edge portions of the shutter are received in channel section guides 14 (one only shown) mounted at opposite sides of the opening on angle section side members 15 which are, in turn, secured to the door jambs or adjacent interior wall surfaces. To protect the lateral edges of the insulation when the shutter is extended and to improve the sealing and appearance of the edges of the assembly, side members 1 5 include a return flange 1 6 spaced to the inner side of guide 14 to overlie the edge portion of the insulating material.

The sealing of the side edges is further improved by the arrangement shown in Figure 2 (shutter edge viewed from exterior side). Each lateral edge of panel structure 10 has, secured to its outer face, a longitudinally extending high tensile steel strip 1 7 bridging the valleys formed by the exterior of corrugations 11 to prevent longitudinal distortion of structure 10. Carried on the outside of this is a plastics rubbing strip 18 having beaded side edges which engages against the outer flange of the guide 14. A similar rubbing strip 1 9 is secured along the inner face of the structure over each corrugation 11 to engage the inner flange of guide 14 (the insulation material 12, 1 3 has its side edge lying just clear of the latter flange).

Said exterior valleys of the corrugations 1 1 have their ends closed by resilient polyethylene plastics foam 20 secured by being compressed beneath strip 17 where the latter is attached to the structure. In this way good sealing within guide 14 is assured and passage of draughts from the outside along the corrugation valleys is prevented.

Tests have shown that the arrangement described is highly durable, the insulation is unaffected by repeated rolling and unrolling cycles of the shutter equivalent to a lengthy operating life and the thermal transmittance (U-value) of a sample of the shutter described was determined under experimental conditions as 0.665 W/M2 per CC and with substantially improved acoustic insulation. If any damage to the insulating sheet material does occur e.g. due to accidental impact or tearing, the affected section can readily be cut out and replaced by a patch with any necessary seam being secured by an adhesive tape.

Claims (13)

1. A roller shutter comprising a longitudinally flexible panel structure capable of being unrolled and rolled for extension and retraction from a coiled condition and having a series of transverse ribs of corrugations parallel to the axis of rolling whose crests lie inwardly of other portions of the panel; and a flexible sheet of insulating material attached at least to said crests on the inner side of the panel to be unrolled and rolled therewith.

2. A shutter as in Claim 1 wherein the panel structure is an effectively continuous metal sheet formed to provide the transverse ribs of corrugations and itself sufficiently flexible to be rolled into the coiled condition.

3. A shutter as in Claim 1 or 3 wherein the insulating material is attached to the crests only of said ribs or corrugations so that it bridges valleys defined therebetween on the inner side when the shutter is uncoiled.

4. A shutter as in Claim 1, 2 or 3 wherein the insulating material includes a layer of resilient foamed plastics material.

5. A shutter as in Claim 4 wherein said plastics material is resilient foamed polyurethane.

6. A shutter as in any preceding claim wherein said insulating material includes a layer of heatreflective material.

7. A shutter as in Claim 6 wherein said heat reflective material is metallised plastics film or metal foil.

8. A shutter as in Claim 6 wherein said heatreflective material is aluminised polyester film.

9. A shutter as in any preceding claim wherein lateral edge portions of the panel structure are provided with sealing and insulation means for co-acting with guide formations in which said edge portions locate when the shutter is uncoiled in use.

10. A shutter as in Claim 9 wherein said sealing means includes a longitudinally extending formation on the outer face of the panel structure bridging valleys formed by the exterior of the ribs or corrugations and insulating material located in at least the end portions of said exterior valleys.

11. A roller shutter substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

12. A roller door installation including a roller shutter as in any preceding claim.

13. A roller door installation substantially as hereinbefore described with reference to and as shown in the accompanying claims.