GB2580949A

GB2580949A - Retractable shutter

Info

Publication number: GB2580949A
Application number: GB1901366.3A
Authority: GB
Inventors: Humphreys Roger
Original assignee: Charter Global Ltd
Current assignee: Charter Global Ltd
Priority date: 2019-01-31
Filing date: 2019-01-31
Publication date: 2020-08-05
Anticipated expiration: 2039-01-31
Also published as: GB201901366D0; GB2580949B

Abstract

The shutter comprises a first 18 and second (20 fig 3a) slat wherein the longitudinal axes of the first and second slats are in alignment. The first slat having a first longitudinally extending edge that is connected to an adjacent longitudinally extending edge of the second slat. Each of the first and second slats comprise an outer shell 102, 104 encasing a core component 106, 108 wherein the core component extends in a longitudinal direction of the respective slat and is provided by a composite material 108 having a polymer matrix and a reinforcing phase 106 embedded therein. The outer shell of the first slat may comprise a first 102 and second 104 section with the sections being discrete components such that an interface is present between any regions of the first and second section that are in contact with each section extending in a longitudinal direction of the first slat. The first section may comprise a channel that extends in a longitudinal direction of the slat where the channel may accommodate the core component.

Description

Retractable Shutter

Field of the Invention

The present invention relates to a retractable shutter comprising multiple slats, and to a method of manufacture of a slat for use in construction of the retractable shutter.

Background to the Invention

Retractable shutters are used generally to provide a movable barrier for opening and closing the entrance to an enclosed area. In many cases, such shutters are roller shutters, that is, they are configured to be rolled up as they are withdrawn from the entrance. Such shutters typically comprise a plurality of slats that are aligned, each slat being connected to at least one adjacent slat via its long edge.

For example, a retractable shutter may be used in garages, car parks, and/or retail environments. In specific applications, it may be necessary for a retractable shutter to achieve a defined security rating, that is, for it to resist attack by potential intruders using tools such as hammers, saws, and/or screwdrivers. Thus, the slats of the shutter need to be configured to provide resistance to attack. At the same time, the selection of materials for the slat is often constrained e.g. by the need to form the slat using a particular process; by the need for the slat to adopt a particular shape; by the need to limit the weight of the shutter; and/or by the need to provide a shutter that may be rolled into a compact cylinder.

Therefore, it is desirable to provide a shutter comprising slats that provide resistance to attack, even when the selection of materials for the slats is constrained by other requirements of the slat.

Summary of the Invention

Therefore, in a first aspect, the present invention may provide a shutter comprising a first slat and a second slat, the longitudinal axes of the first and second slats being in alignment, the first slat having a first longitudinally-extending edge that is connected to an adjacent longitudinally-extending edge of the second slat; each of the first and second slats comprising an outer shell encasing a core component, wherein the core component extends in a longitudinal direction of the respective slat and is provided by a composite material having a polymer matrix and a reinforcing phase embedded therein.

The presence of a core component comprising a reinforcing phase that is bound by a polymer matrix may provide the slat with resistance to attack, even if the selection of the material for the outer shell of the slats is constrained by the need for the outer shell to have a particular shape or to be manufactured using a specific process. Furthermore, the presence of the core component may provide the shutter with increased resistance to attack, while allowing the weight and/or dimensions of the shutter to be maintained within desired limits.

Typically, the reinforcing phase comprises particles, e.g. of a mineral or ceramic material.

For example, the reinforcing phase may be provided by aluminium oxide particles. In general, the polymer matrix is a thermosetting resin, such as an epoxy resin.

Typically, the outer shell of the first slat comprises a first section and a second section, the first section and second section being discrete components, such that an interface is present between any regions of the first section and second section that are in contact, each section extending in a longitudinal direction of the first slat.

In general, the first section defines a channel that extends in a longitudinal direction of the slat, the channel accommodating the core component.

In certain embodiments, the surface of the channel that is directed towards the core component is at least partly lined with a mesh. That is, the mesh lies adjacent to the inner surface of the channel (the inner surface of the channel being generally concave) and conforms to the shape of that surface. Typically, the mesh comprises steel as its principal component. In certain cases, the mesh is galvanised. The mesh may be provided e.g. by interwoven strands. In other embodiments, the mesh may be provided by a sheet of material having multiple through-thickness apertures.

In general, the second section bridges the sides of the channel defined by the first section. For example, features of the second section may interconnect with features provided on the sides of the channel defined by the first section.

In general, the first section is provided by an extruded aluminium component. The aluminium surface may be provided with a polymer coating, e.g. a polyester coating, which is considered to increase resistance to environmental degradation. Alternatively, the aluminium surface may be anodised.

The first section may comprise one or more longitudinally-extending cavities, each cavity being bounded from the core component by a dividing wall and each cavity being configured to accommodate a respective reinforcing bar. Preferably, the reinforcing bar is provided by a strong material that resists cutting. For example, the reinforcing bar may be provided by a steel component.

Typically, the second section is provided by a steel component, preferably a stainless steel component, more preferably cold-rolled stainless steel.

Typically, the second slat has the same configuration as the first slat.

The use of aluminium for the first section of the outer shell is particularly preferred in the case that the shutter is configured as a self-locking shutter.

Such shutters are typically configured such that the first longitudinally-extending edge of the first slat is connected to the adjacent longitudinally-extending edge of the second slat via an elongate connecting element that is aligned with the longitudinal direction of the first and second slats; the maximum transverse dimension of the elongate connecting element being less than the maximum transverse dimension of either one of the first and second slats; wherein the first longitudinally-extending edge of the first slat and the adjacent longitudinally-extending edge of the second slat are each provided with a hook element that curves about the longitudinal direction of the slats along a first direction of rotation; and the connecting element is provided with a first hook element and a second hook element, the first hook element curving about the longitudinal direction of the connecting element along the first direction of rotation and being interconnected with the hook element of the first slat; the second hook element curving about the longitudinal direction along the first direction of rotation and being interconnected with the hook element of the second slat.

The requirement in such cases to provide slats having complex shapes, typically including integral hook elements, generally places limitations on the materials and/or processes that may be used in the formation of the slats. Typically, in such cases, the most effective way to provide the complex shape of the slat may be through extrusion of the relevant part. It is known in the art that aluminium is well-suited to extrusion processes. However, aluminium typically displays lower strength than other metals such as steel: thus, the provision of a core component comprising a reinforcing phase may assist in off-setting this perceived disadvantage of aluminium.

In a second aspect, the present invention may provide a method of manufacturing a slat for use in constructing a shutter according to the first aspect of the invention, comprising the steps of: * providing a first section and a second section that are configured to be assembled to provide the outer shell of the slat, the first section comprising a longitudinally-extending channel; * depositing a loose mass of a reinforcing phase into the channel; * pouring a liquid binder over the loose mass of the reinforcing phase; * allowing the liquid binder to set to provide a polymer matrix having the reinforcing phase embedded therein; and * before or after the step of allowing the liquid binder to set, connecting the second section to the first section to form the outer shell, such that the second section bridges the sides of the channel.

Preferably, the method further comprises the step, before the step of depositing the loose mass of the reinforcing phase into the channel, of at least partially lining the inner surface of the channel with a mesh and depositing the loose mass of the reinforcing phase over the mesh.

The shutter, the slat, the first and second sections of the slat, the reinforcing phase, the polymer matrix and the mesh may each have one or more of the optional features of the corresponding component of the first aspect of the invention.

Detailed Description

The invention will now be described by way of example with reference to the following Figures in which: Figure 1 shows a schematic front elevation view of an entrance comprising a shutter according to a first embodiment of the first aspect of the invention, the entrance being in the closed configuration; Figure 2 shows a schematic cross-sectional view of an individual slat of the shutter in the entrance of Figure 1; Figure 3a shows a schematic cross-sectional view of a portion of the entrance of Figure 1, the shutter being held in a first configuration.

Figure 3b shows the same view as Figure 3a, but indicating different features.

Figure 4 shows the same view as Figures 3a and 3b, the shutter being held in a second configuration; Figure 5 shows a schematic cross-sectional view of an individual slat of a shutter according to a second embodiment of the first aspect of the invention.

Referring to Figure 1, an entrance 10 comprises a roller shutter 12 that spans the aperture between guide channels 13a,b. The roller shutter comprises a plurality of slats 18,20, each pair of adjacent slats having a connecting element 22 therebetween. When in the retracted position, the shutter is rolled in a cylindrical configuration and stowed in box 25.

Figure 2 shows a cross-sectional view of slat 18 (slats 18 and 20 both having the same configuration). Slat 18 has an outer shell that is provided by a first section 102 and a second section 104. The first section 102 is formed from extruded aluminium (optionally coated with a polymer coating, e.g. a polyester coating). The first section 102 comprises a portion that is C-shaped in cross-section (the view of Figure 2 shows this as an inverted C): this portion has a curved back 34 and two sidewalls 35a,b that extend from opposed straight edges of the back 34. Sidewalls 35a,b are on the same side of the curved back 34. The curved back 34 and the two sidewalls 35a,b define a channel therebetween, the channel extending in a longitudinal direction of the slat 18.

A mesh of galvanised steel 106 lines the concave surface of the curved back 34 (Figure 2 shows individual strands of the mesh in cross-section). The remainder of the channel defined by the first section 102 is filled with a filler 108 that is provided by a composite material in which aggregate particles are bound together with an epoxy resin.

The outer shell of the slat 18 is completed by a steel panel 104 that bridges the two sidewalls 35a,b. Effectively, the steel panel 104 caps the channel, such that mesh 106 and filler 108 are located within the outer shell defined by first section 102 and steel plate 104.

Each longitudinally-extending edge of the steel plate is held in place by a respective pair of protrusions 110a,b extending inwardly from each respective sidewall 35a,b.

The longitudinally-extending edges of slat 18 are each provided with hook elements 24a,b.

The hook elements are each curved about the longitudinal direction of the slat in an anti-clockwise direction from their base to their free end. Hook element 24a extends from the junction between sidewall 35a and curved back 34, while hook element 24b extends from the free end of sidewall 35b.

Figure 3a shows a cross-sectional view of a longitudinal end of each of first slat 18, second slat 20 and connecting element 22, held between guide walls 14,16 of guide channel 13a.

Elongate connecting element 22 is positioned between and connects the first and second slats to each other. The first and second slats and the elongate connecting element are in longitudinal alignment with each other.

One longitudinal end of each of the slats 18,20 and the connecting element 22 is held within the guide channel 13a, while the opposing end of the respective slat or connecting element is held within guide channel 13b. The intermediate section of each slat or connecting element serves to bridge the gap between the first and second guide channels, so that entrance 10 is in a closed configuration.

The longitudinally-extending edges of the first and second slats are each provided with hook elements 24a,b and 26a,b. The hook elements are each curved about the longitudinal direction of the slats in an anti-clockwise direction from their base to their free end.

The connecting element 22 is also provided with two hook elements 28a,b, each hook element being curved about the longitudinal direction of the connecting element, in an anticlockwise direction from its base to its free end. The two hook elements 28a,b provide the connecting element with a cross-section that is approximately in the shape of an inverted S. Hook element 24b of the first slat 18 is interconnected with hook element 28a of the connecting element 22, while hook element 28b of the connecting element 22 is interconnected with hook element 26b of the second slat 20. Thus, first and second slats 18,20 are connected via connecting element 22.

To assemble the entrance 10, the first and second guide channels 13a,b are secured to opposed edges of the opening to be secured. Connecting element 22 is hooked onto first slat 18 through the interconnection of hook elements 24b and 28a, and second slat 20 is hooked onto connecting element 22 through the interconnection of hook elements 28a and 26b, thus forming a roller shutter 12. Further slats and connecting elements may be added to the roller shutter in like manner, by alternating slats and connecting elements.

The longitudinal ends of roller shutter 12 are fed into the first and second guide channels 13a,b.

Figures 3a and 3b show the configuration of the roller shutter when it is subjected to a tensile force FT, e.g. when the roller shutter is being raised from above, for example by means of an electric motor. The weight of the roller shutter and the tensile force act to pull the shutter to its maximum length. This causes connecting element 22 to become oriented such that its maximum transverse dimension (which is disposed along the line A-A) is brought into closer alignment with guide walls 14,16. Thus, the roller shutter passes easily between guide walls 14,16.

Figure 4 shows the configuration of the roller shutter when it is subjected to a compressive stress Fc, e.g. when an attempt is being made to raise the roller shutter by pushing it from below. This action forces first and second slats 18,20 closer together, so as to turn connecting element 22 about its longitudinal axis in the direction given by arrow B. Thus, the maximum transverse dimension of the connecting element (which is disposed along the line A-A) extends further across the guide channel than is the case for the configuration shown in Figures 2a and 2b. This causes connecting element 22 to become wedged between guide walls 14,16, thus resisting the action of compressive force Fc and inhibiting further upward motion of the roller shutter 12.

If an attempt is made to breach the roller shutter 12, resistance to cutting operations will be provided by the steel mesh 106, while the composite filler 108 provides resistance to both drilling and cutting operations, as the presence of aggregate within the filler will tend to blunt the sharp edges on any instrument being used.

Slat 18 is manufactured by providing first section 102 and resting it on the curved back 34, such that sidewalls 35a,b extend upwardly. Mesh 106 is placed on the concave surface of curved back 34, after which aggregate is deposited into the channel defined by curved back 34 and side walls 35a,b. A two-part epoxy resin is prepared and poured over the aggregate present in the channel and allowed to penetrate the aggregate. Steel plate 104 is made to slide in a longitudinal direction of slat 18, passing between protrusions 110a,b on sidewall 35a and the corresponding protrusions on sidewall 35b. The assembly is then left to allow the epoxy resin to cure.

Once curing is complete, the shutter is assembled by alternating slats with connecting elements and die-cast end locks are secured to the longitudinal ends of the slats to maintain the assembly in alignment.

Figure 5 shows a slat 180 that is a variant of the slat of Figure 2. Like numerals indicate like features. The slat 180 differs from the slat of Figure 2 principally in that the first section 1020 comprises two longitudinally-extending cavities la and 1b, each cavity being located inwardly of a respective sidewall 35a,b.

Cavity la is bounded by: sidewall 35a; the portion of the curved back 34 adjacent to sidewall 35a; and enclosing walls 15a,b. Enclosing wall 15a extends in a laterally inward direction of sidewall 35a, and in conjunction with protrusion 110a, holds steel wall 104 in place. Thus protrusion 110b (shown in Figure 2) is not required. Enclosing walls 15a,b provide a boundary between cavity la and the composite filler 108.

Cavity 1 b is similarly bounded by: sidewall 35b; the portion of curved back 34 adjacent to sidewall 35b and enclosing walls.

Cavities la,b are each configured to accommodate a respective reinforcing bar that extends in a longitudinal direction of the slat, for example, a steel bar.

Claims

CLAIMS1. A shutter comprising a first slat and a second slat, the longitudinal axes of the first and second slats being in alignment, the first slat having a first longitudinally-extending edge that is connected to an adjacent longitudinally-extending edge of the second slat; each of the first and second slats comprising an outer shell encasing a core component, wherein the core component extends in a longitudinal direction of the respective slat and is provided by a composite material having a polymer matrix and a reinforcing phase embedded therein.
2. A shutter according to claim 1, wherein the outer shell of the first slat comprises a first section and a second section, the first section and second section being discrete components, such that an interface is present between any regions of the first section and second section that are in contact, each section extending in a longitudinal direction of the first slat.
A shutter according to claim 2, wherein the first section comprises a channel that extends in a longitudinal direction of the slat, the channel accommodating the core component.
4. A shutter according to claim 3, wherein the surface of the channel that is directed towards the core component is at least partly lined with a mesh.
5. A shutter according to claim 4, wherein the mesh comprises steel as its principal component.
6. A shutter according to claim 5, wherein the mesh is galvanised.
7. A shutter according to any one of claims 3-6, wherein the second section bridges the sides of the channel provided in the first section.
8. A shutter according to any one of claims 2-7, wherein the first section is provided by an extruded aluminium component.
9. A shutter according to claim 8, wherein the first section is provided with a polymer coating, e.g. a polyester coating.
10. A shutter according to any one of claims 2-9, wherein the second section is provided by a steel component.
11. A shutter according to any one of the preceding claims, wherein the polymer matrix is a thermosetting resin.
12. A shutter according to claim 11, wherein the thermosetting resin is an epoxy resin.
13. A shutter according to any one of the preceding claims, wherein the reinforcing phase comprises reinforcing particles.
14. A shutter according to claim 13, wherein the particles are provided by a ceramic material, such as aluminium oxide.
15. A shutter according to any one of the preceding claims, wherein the first longitudinally-extending edge of the first slat is connected to the adjacent longitudinally-extending edge of the second slat via an elongate connecting element that is aligned with the longitudinal direction of the first and second slats; the maximum transverse dimension of the elongate connecting element being less than the maximum transverse dimension of either one of the first and second slats; wherein the first longitudinally-extending edge of the first slat and the adjacent longitudinally-extending edge of the second slat are each provided with a hook element that curves about the longitudinal direction of the slats along a first direction of rotation; and the connecting element is provided with a first hook element and a second hook element, the first hook element curving about the longitudinal direction along the first direction of rotation and being interconnected with the hook element of the first slat; the second hook element curving about the longitudinal direction along the first direction of rotation and being interconnected with the hook element of the second slat.
16. A method of manufacturing a slat for use in constructing a shutter according to any one of claims 3-7, comprising the steps of: * providing a first section and a second section that are configured to be assembled to provide the outer shell of the slat, the first section comprising a longitudinally-extending channel; * depositing a loose mass of a reinforcing phase into the channel; * pouring a liquid binder over the loose mass of the reinforcing phase; * allowing the liquid binder to set to provide a polymer matrix having the reinforcing phase embedded therein; and * before or after the step of allowing the liquid binder to set, connecting the second section to the first section to form the outer shell, such that the second section bridges the sides of the channel.
17. A method according to claim 16, further comprising the step, before the step of depositing a loose mass of reinforcing material into the channel, of at least partially lining the inner surface of the channel with a mesh.
18. A method according to claim 16 or claim 17, wherein the first section is provided by an extruded aluminium component.
19. A method according to claim 18, wherein the first section is provided with a polymer coating, e.g. a polyester coating.
20. A method according to any one of claims 16-19, wherein the second section is provided by a steel component.
21. A method according to any one of the claims 16-19, wherein the polymer matrix is a thermosetting resin.
22. A method according to claim 21, wherein the thermosetting resin is an epoxy resin.
23. A method according to any one of claims 16-22, wherein the reinforcing phase comprises reinforcing particles.
24. A method according to claim 16-23, wherein the particles are provided by a ceramic material.
25. A method according to any one of claims 16-24, wherein the slat has opposed longitudinally-extending edges, each edge being provided with a respective hook element that curves about the longitudinal direction of the slat along a first direction of rotation.