WO2006063413A1

WO2006063413A1 - Insert for intruder resistant screen

Info

Publication number: WO2006063413A1
Application number: PCT/AU2005/001911
Authority: WO
Inventors: Peter Bouma; Richard Dinning; Len Peers; Steven Brabeck
Original assignee: Crimsafe Security Systems Pty Ltd; Pacific Plastics Pty Ltd
Priority date: 2004-12-16
Filing date: 2005-12-16
Publication date: 2006-06-22
Also published as: CA2591019A1

Abstract

An insert (20) for an intruder resistant screen comprises an elongate member (21) being of plastics material and a first lip section (24) and a second (25) lip section extending from a first surface (22) of the elongate member for holding the insert to a first portion (6) of the screen. The insert comprises a third lip section (26) extending from the first surface of the elongate member (21) for holding the insert to a second portion (7) of the screen. In use, the elongate member (21) is foldable about a point (39) intermediate the first and third lip sections to prevent contact between mesh (4) of the screen and the first and second portions (6, 7) to inhibit corrosion.

Description

TITLE INSERT FOR INTRUDER RESISTANT SCREEN

FIELD OF THE INVENTION THIS INVENTION relates to an insert for an intruder resistant screen, the screen being particularly useful for both security and insect screening of windows, doorways and the like.

BACKGROUND OF THE INVENTION Screens or grilles are sometimes used to improve the security of a building. For example, steel bar grilles have been used to deter intruders from entering premises through a window or door. However, steel bar grilles are generally considered unsightly and are therefore usually only used in industrial or commercial settings. Furthermore, such grilles do not always provide adequate security. Conventional security screens provide an aesthetic alternative, but they also do not always provide adequate security and can be labour intensive to produce.

A further disadvantage is that the above described screens or grilles are not effective for insect screening and therefore fine mesh screens are sometimes used in conjunction with security screens or grilles. However, the above fine mesh screens are not intruder resistant. Accordingly, to provide limited security and insect screening both fine mesh screens and security screens or grilles are often used which increases the manufacturing and/or installation costs. A solution to the problems evident in the prior art has been described in our Australian Patent Number 694515 which describes an intruder resistant screen incorporating a woven wire intruder resistant mesh clamped between a plurality of clamping portions and clamping members with leveraged clamping action.

However, the inventors have found that such screens can be susceptible to the problem of corrosion. Corrosion typically occurs through an electrolytic reaction where two different metal types contact each other. Such corrosion can occur in the screen of aforementioned Australian Patent Number 694515 where the steel mesh and the aluminium frame are in contact. Furthermore, the problem of corrosion can be exacerbated by the ingress of moisture.

One attempt to address the problem of corrosion involves placing one or more strips of waterproof material between the steel mesh and the aluminium frame to prevent contact. However, the employment of such strips has in fact been found to exacerbate the problem of corrosion through the failure of the strips to prevent the ingress of moisture and through the strips maintaining the moisture in contact with the steel mesh and aluminium frame. Furthermore, correct positioning of such strips can be difficult and the use of such strips is found to hinder the insertion of the mesh and the clamping member. For example, the strips are often found to bunch up when the mesh and/or the clamping member are inserted. Both of these factors increase the production times for the intruder resistant screen, thus reducing production efficiency.

Hence, there is a need to address or at least ameliorate one or more of the aforementioned problems of the aforementioned intruder resistant screen.

SUMMARY OF THE INVENTION

According to one aspect of the invention there is provided an insert for an intruder resistant screen, said insert comprising: an elongate member being of plastics material; first and second lip sections extending from a first surface of said elongate member for holding said insert to a first portion of said screen; and a third lip section extending from said first surface of said elongate member for holding said insert to a second portion of said screen; wherein, in use, said elongate member is foldable about a point intermediate said first and third lip sections to prevent contact between mesh of said screen and said first and second portions to inhibit corrosion.

Preferably, the first lip section and/or the third lip section comprise a curved or sloping side to help minimise the ingress of moisture between the first and second portions and the mesh. Suitably, minimisation of the ingress of moisture is also helped by a soft elongate member provided at the first and third lip sections adjacent a second surface of said elongate member opposite said first surface, wherein, in use, the soft elongate member at least partially fills holes in the mesh.

The insert preferably further comprises at least one notch in the elongate member about which the elongate member is foldable.

Suitably, the at least one notch is substantially v-shaped.

Preferably, the at least one notch is provided in the second surface of the elongate member. The first lip section is preferably provided towards a first end of said elongate member and the third lip section is provided towards an opposite second end of the elongate member.

Suitably, the second lip section extends from the elongate member at a point closer to the first lip section than to the third lip section. The plastics material is preferably Santoprene® thermoplastic rubber.

Suitably, the first and third lip sections comprise a protrusion extending from the second surface of the elongate member.

Preferably, the soft elongate member is provided on the protrusions extending from the second surface of the elongate member at the first and third lip sections.

According to another aspect of the invention there is provided an insert for an intruder resistant screen, said insert comprising: an elongate member being of plastics material; first, second and third lip sections extending from a first surface of said elongate member, said first lip section provided toward a first end of said elongate member, said second lip section provided toward an opposite, second end of said elongate member and said third lip section provided intermediate said first and second lip sections; said first and third lip sections each having a surface substantially perpendicular to said first surface and a surface inclined with respect to said first surface; said second lip section extending substantially perpendicular from said first surface; wherein, in use, said first and second lip sections cooperate to hold said insert to a first portion of said screen and said third lip section holds said insert to a second portion of said screen; and wherein, in use, said elongate member is foldable about a point intermediate said second and third lip sections to prevent contact between mesh of said screen and said first and second portions to inhibit corrosion.

Further features of the present invention will become apparent from the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be readily understood and put into practical effect, reference will now be made to preferred embodiments that are provided by way of example only in which:

FIG 1 is a perspective view of an intruder resistant screen; FIG 2 is an exploded perspective view of the screen of FIG 1 illustrating the formation of a corner section of the screen;

FIG 3 is an end view of an insert for the intruder resistant screen of FIG 1 in accordance with an embodiment of the invention;

FIGS 4 and 5 are perspective views of the insert of FIG 3;

FIG 6 is a perspective view of an alternative embodiment of the insert; FIG 7 is a partial cross sectional view through A-A of FIG 1 illustrating the insert of FIG 3 in a closed position;

FIG 8 is a partial cross sectional view through A-A of FIG 1 illustrating the insert of FIG 3 in an open position; and FIGS 9 and 10 are perspective views of an embodiment of an insert for the corner sections of the screen.

DETAILED DESCRIPTION OF THE INVENTION With reference to FIG 1 there is illustrated an intruder resistant screen 1 having a frame 2 comprised of elongate frame members 3 with an intruder resistant mesh 4 clamped to frame members 3.

Mesh 4 covers the opening enclosed by frame 2. Mesh 4 is a woven grid of stainless steel wire. Suitable mesh dimensions have been described in Australian Patent 694515. The most suitable dimensions have been found to be wire diameters from 0.8mm to 1.2mm and wire spacing (in weft or warp) from 1 mm to 2.2mm.

With reference to FIG 2, according to one embodiment, frame member 3 is formed from extruded aluminium and has a channel section 5 for receiving a corner stake 10 at each of its ends. Accordingly, frame 2 is formed to a desired shape and dimensions by cutting suitable lengths of each frame member 3 and assembling the lengths with mitred corners.

Although frame members 3 are preferably extruded aluminium lengths, they can be extruded, roll formed or press formed lengths of any suitable material.

Located inwardly of channel 5 is a first portion of the screen in the form of an integral clamping portion 6 and a second portion of the screen in the form of non-integral clamping member 7, which is separately formed from frame member 3. The clamping portion 6 and the clamping member 7 are of an identical length and extend along the length of frame member 3. Spaced holes are drilled along the clamping portions 6 and the clamping members 7 to receive fastening means 8 in the form of pop-rivets or screws, which co- act with the clamping portions 6 and the clamping members 7 to clamp mesh 4 to frame 2. Hence, when clamped, an area adjacent each respective edge of mesh 4 is clamped to frame 2 such that each clamped area is in the same plane as the rest of mesh 4 which is enclosed by frame 2. As a result, each edge of mesh 4 is clamped to no more than one clamping surface of each one of clamping portions 6 and clamping members 7.

According to one embodiment, a surface of the clamping portion 6 is serrated to provide stronger retention of mesh 4. A surface of the clamping member 7 can also be serrated, as shown in FIG 7. The serrations on the clamping portion 6 and the clamping member 7 act together to firmly hold the mesh 4 in the frame member 3. The fastening means 8 holds the clamping member 7 in position against the clamping portion 6 with the result that the mesh can withstand significant impact and not be pulled from the frame. An integral wall section 9 extends inwardly from the channel section 5.

At the free end of wall section 9 is a flange section 11 which extends towards mesh 4 and supports clamping portion 6.

A tongue 12, integral with and extending inwardly from channel section 5, forms with wall section 9 a recess 13 which accommodates an edge of clamping member 7 and an edge of mesh 4. Tongue 12 abuts clamping member 7 and assists in keeping clamping portion 6 and clamping members 7 parallel during clamping. Tongue 12 can extend inwardly from channel section 5 as a continuation of one of the walls of channel section 5, as shown in FIG 2. Alternatively, tongue 12 can extend inwardly from channel section 5 as a separate projection, as shown in FIGS 7 and 8.

With reference to FIG 7, in one embodiment, tongue 12 terminates in hook 18 which seats in slot 19 of the clamping member 7 to positively locate the clamping member 7 with respect to the frame 3 and thus clamping portion 6. The hook and slot combination assist to provide strong leveraged clamping of the mesh 4 by providing a pivot point forthe clamping member 7.

Referring to FIGS 3-10, to address the aforementioned problem of corrosion that can occur at the points of contact between the stainless steel mesh 4 and the aluminium frame member 3, an insert 20 is provided to prevent contact between the clamping portion 6 and the clamping member 7 along the length of the frame members 3. In one embodiment, insert 20 is in the form of an extrusion of flexible Santoprene® thermoplastic rubber. However, it is envisaged that alternative flexible, waterproof plastics materials can be employed, such as PVC or other rubber materials. Referring to FIG 3, insert 20 comprises an elongate member 21 having first lip section 24, a second lip section 25 and a third lip section 26 extending substantially perpendicularly from a first surface 22 of the elongate member 21. First lip section 24 is provided towards a first end of the elongate member 21 and the third lip section 26 is provided towards an opposite second end of the elongate member 21. Second lip section 25 is provided intermediate the first and second ends of the elongate member 21. First and second lip sections 24, 25 cooperate to hold the insert 20 to the first portion 6 of the screen 1 and third lip section 26 is for holding the insert 20 to the second portion 7 of the screen 1.

First and third lip sections 24, 26 each comprise a substantially planar first side 35 substantially perpendicular to first surface 22 and an inclined or sloping second side 36. In an alternative embodiment, side 36 can be curved rather than planar, the curve being slightly concave and sloping in the same direction as the sloping side. The curved or sloping sides 36 help minimise the ingress of moisture between the first and second portions 6, 7 and the mesh 4.

First and third lip sections 24, 26 each comprise a protrusion 37 extending from a second surface 23 of the elongate member 21 , the second surface 23 being opposite the first surface 22. Protrusions 37 abut mesh 4 when the insert 20 is in use which forces first sides 35 of first and third lip sections 24, 26 against an end surface of flange 11 and an end surface of clamping member 7 respectively to help prevent the ingress of moisture as described in more detail hereinafter. Second lip section 25 is substantially planar on both sides and substantially perpendicular to first surface 22, but comprises a hook 38 at an end distal the elongate member 21 to aid holding of the insert 20 to the first portion 6 of the screen 1.

The insert 20 comprises at least one notch 39 in the elongate member 21 about which the elongate member is foldable. The at least one notch 39 is provided in the second surface 23 of the elongate member 21 intermediate the first and third lip sections 24, 25 and in the embodiments shown, the at least one notch 39 is provided intermediate the second and third lip sections 25, 26. According to one embodiment, the at least one notch is substantially v-shaped, although other notch shapes can also be employed to allow the insert to be folded. FIGS 3-5 show an embodiment of the insert comprising a single notch 39 and FIG 6 shows an alternative embodiment comprising two notches 39. Referring to FIG 7, in use, insert 20 is foldable about a point intermediate the first and third lip sections 24, 26 about the at least one notch 39 such that mesh 4 is surrounded by elongate member 21 of the insert 20 to prevent contact between the mesh 4 and the frame member 3 to inhibit corrosion. Insert 20 in particular prevents contact between the mesh 4 of the screen and the first portion of the screen, clamping portion 6 and between the mesh 4 and the second portion of the screen, clamping member 7.

According to one embodiment, the insert 20 further comprises a soft elongate member 40 on and/or around the protrusions 37 of the first and third lip sections 24, 26 along the length of the insert 20. When the integral clamping portion 6 and the non-integral clamping member 7 are clamped together, soft elongate member 40 is compressed and fills, or at least partially fills, holes in the mesh 4 to help minimise the ingress of moisture between the clamping portion 6, non-integral clamping member 7 and the mesh 4. Although FIG 7 shows the protrusions 37 and soft elongate member 40 of the first and third lip sections 24, 26 to be at different levels, it is preferred that the protrusions 37 and soft elongate members 40 be at substantially the same level to provide an optimum seal against the mesh 4. In one embodiment, the soft elongate member 40 is formed of a softer grade flexible, waterproof plastics material than the rest of the insert and can be co- extruded with the insert 20. In a preferred embodiment, the soft elongate member 40 is formed of a softer grade Santoprene® thermoplastic rubber than the Santoprene® thermoplastic rubber comprising the remainder of the insert 20.

With reference to FIG 8, when elongate member 21 of the insert 20 is in place with first and second lip sections 24, 25 holding the insert 20 about clamping portion 6, the insert 20 is folded about notch 39 to facilitate easy insertion of the mesh 4. Once the mesh 4 is inserted, the second end of the flexible insert comprising third lip section 26 is folded back towards the first and second lip sections 24, 25 and the inserted mesh 4 to facilitate location of the clamping member 7. Clamping member 7 clips between hook 18 of frame member 3 and third lip section 26 of insert 20, as shown in FIG 7. First and third lip sections 24, 26 provide a seal between the mesh 4 and clamping portion 6 and between the mesh 4 and the clamping member 7. Curved or sloping second sides 36 slope away from mesh 4 thus encouraging water to flow away from the mesh 4. Soft elongate members 40 on the second surface 23 of the elongate member 21 are clamped between the insert and the mesh 4 thus filling the holes in the mesh to further help minimise the ingress of moisture.

With reference to FIG 4, to accommodate the inserts 20 at the corner sections of the frame 2 of the screen 1 , according to one embodiment, the ends of lengths of the insert 20 are cut at 45 degrees along the dotted lines whilst the insert is flat. Hence, when the insert 20 is folded, a mitre joint is produced with an adjacent length of insert cut at the end in the same manner.

FIGS 9 and 10 show another embodiment of the insert 20 for the corner sections of the frame 2 of the screen 1. These embodiments have the same features of the aforementioned embodiments, but instead of being extruded in lengths, the inserts for the comer sections are formed as T- shapes such that, when folded, they provide a continuous seal at the corner sections of the frame 2. A join between two adjacent inserts at the corner of the frame 2 is undesirable because the frame is particularly susceptible to the ingress of moisture at the corners. The embodiments shown in FIGS 9 and 10 comprise two notches 39, but can comprise a single notch 39 in an alternative embodiment.

Hence, insert 20 of the present invention inhibits corrosion that can occur at the points of contact between the stainless steel mesh 4 and the aluminium frame members 3 by presenting a barrier between the two types of metal to prevent the aforementioned electrolytic reaction. Elongate member 21 surrounds the mesh 4 to help minimise the ingress of moisture and inhibit corrosion. Curved or sloping second sides 36 further help to inhibit corrosion by minimising the ingress of moisture between the first and second portions of the screen and the mesh. Soft elongate members 40 further inhibit the ingress of moisture. Furthermore, first and second lip sections 24, 25 help to hold the insert 20 on the clamping portion 6 and third lip section 26 holds the insert 20 to the clamping member 7. Easy insertion of mesh 4 is facilitated by the foldable nature of the flexible Santoprene® thermoplastic rubber forming the insert 20 and the notch 39 facilitates folding of the insert, thus positively contributing to the process of fabricating the screen.

In use intruder resistant screen 1 can be mounted on hinges in a doorway or secured in any known manner to a window frame. Mesh 4 provides difficulties for intruders as a sufficiently large hole to gain entry cannot be easily sawn or cut by bolt cutters due to the mesh grade which also provides insect screening. Furthermore, when stainless steel mesh 4 is used these difficulties for potential intruders can be compounded due to the properties of stainless steel which can blunt cutting tools.

The clamping of the mesh provides additional intruder resistance as wall sections 9 are located on the outside of the doorway or window so that fastening means 8 are concealed from a potential intruder. When viewed on the inside, fastening means 8 are hidden by a cover which is of a colour matching clamping member 7.

Although the invention has been described with reference to preferred embodiments, it is to be understood that the invention is not limited to the specific embodiments described herein.

Claims

CLAIMS:

1. An insert for an intruder resistant screen, said insert comprising: an elongate member being of plastics material; first and second lip sections extending from a first surface of said elongate member for holding said insert to a first portion of said screen; and a third lip section extending from said first surface of said elongate member for holding said insert to a second portion of said screen; wherein, in use, said elongate member is foldable about a point intermediate said first and third lip sections to prevent contact between mesh of said screen and said first and second portions to inhibit corrosion.

2. The insert of claim 1 , wherein the first lip section comprises a curved or sloping side to help minimise the ingress of moisture between the first and second portions and the mesh.

3. The insert of claim 1 , wherein the third lip section comprises a curved or sloping side to help minimise the ingress of moisture between the first and second portions and the mesh.

4. The insert of claim 1 , further comprising at least one notch in the elongate member about which the elongate member is foldable.

5. The insert of claim 5, wherein the at least one notch is substantially v- shaped.

6. The insert of claim 5, wherein the at least one notch is provided in the second surface of the elongate member.

7. The insert of claim 1 , wherein the first lip section is provided towards a first end of said elongate member and the third lip section is provided towards an opposite second end of the elongate member.

8. The insert of claim 1 , wherein the second lip section extends from the elongate member at a point closer to the first lip section than to the third lip section.

9. The insert of claim 1 , wherein the plastics material is Santoprene® thermoplastic rubber.

10. The insert of claim 1 , wherein the first and third lip sections comprise a protrusion extending from the second surface of the elongate member.

11. The insert of claim 1 , wherein minimisation of the ingress of moisture is helped by a soft elongate member provided at the first and third lip sections adjacent a second surface of said elongate member opposite said first surface, wherein, in use, the soft elongate member at least partially fills holes in the mesh.

12. The insert of claim 11 , wherein the soft elongate member is provided on a protrusion extending from the second surface of the elongate member at the first and third lip sections.

13. The insert of claim 11 , wherein the soft elongate member is formed of a softer plastics material than the remainder of the insert.

14. An insert for an intruder resistant screen, said insert comprising: an elongate member being of plastics material; first, second and third lip sections extending from a first surface of said elongate member, said first lip section provided toward a first end of said elongate member, said second lip section provided toward an opposite, second end of said elongate member and said third lip section provided intermediate said first and second lip sections; said first and third lip sections each having a surface substantially perpendicular to said first surface and a surface inclined with respect to said first surface; said second lip section extending substantially perpendicular from said first surface; wherein, in use, said first and second lip sections cooperate to hold said insert to a first portion of said screen and said third lip section holds said insert to a second portion of said screen; and wherein, in use, said elongate member is foldable about a point intermediate said second and third lip sections to prevent contact between mesh of said screen and said first and second portions to inhibit corrosion.

Dated this Sixteenth day of December 2005 CRIMSAFE SECURITY SYSTEMS PTY LTD

AND PACIFIC PLASTICS PTY LTD

By their Patent Attorneys FISHER ADAMS KELLY