AU2006235977B2 - Security Mesh with Improved Edge Attachment - Google Patents

Description

Security Mesh with Improved Edge Attachment Z Field of the Invention.

._This invention is directed to a security window or security door or a security panel which contains a security mesh attached to a surround frame, and the invention is particularly directed to an improved method of attaching the security mesh to the surround frame. The invention will be described with reference to a window or door security screen, although it should be appreciated that no particular limitation is meant I thereby, and the invention can extend to other types of openings and the like that 10 would benefit from a security screen.

Background Art.

Security screens are well known in the marketplace. Traditionally, the security screens are made of steel bars or rods which are attached on the outside or inside of a window to prevent entry. More recently, a relatively rigid aluminium screen has been used, and a typical screen is known under the trade mark AMPLIMESH. More recently again, it has become quite popular to use a woven stainless steel mesh as a security screen. The stainless steel mesh can double up as a fly screen and means that unsightly steel bars are not required and the aluminium screen (which is also quite unsightly) is no longer required. The stainless steel mesh is typically black or grey and is still quite transparent, allows ventilation, and is quite efficient as a security screen.

However, the main weakness with a security screen made from woven steel mesh (or other type of material) is in the attachment of the mesh to the frame. To explain, the security screen will typically comprise a surround frame and the mesh is attached to the surround frame. Fasteners rivets, screws etc) have been used but suffer from a number of disadvantages. One disadvantage is in the time required to assemble such a frame. Another disadvantage is that the fasteners can be "drilled out" to enable the mesh to be pushed out of the surround frame. Another disadvantage is that the mesh is only attached to the surround frame at the fasteners. Fasteners are also unsightly.

For this reason, it is also known to provide some form of wedge which is pushed into N 2 a channel on the surround frame. The edge of the mesh is placed in the channel and the wedge is driven in to lock the mesh in place. Some sort of means is provided to Z prevent the wedge from being removed. An advantage of this arrangement is that the mesh is attached in a fairly continuous manner and does not rely on separate spaced apart fasteners.

Application 78780/98 describes such an arrangement. To enable the wedge to securely clamp the mesh, the free end of the mesh must be bent back almost into a V shape.

IDApplication 200235592 is similar except that the edge of the mesh is L shaped. The main disadvantage with these systems is that, since the wedge is pushed into the groove, great care must be taken to ensure that the wedge cannot be prised out, because if it is, the mesh can be removed easily with loss of security. Thus, the channel in the surround frame needs to be made of a complicated profile having multiple rows of teeth and the wedge also needs to be made of a complicated profile.

As the frame channel is quite small, the teeth are quite small and any variation in the manufacturing process may cause the teeth to not work properly. Also any grime etc buildup in the channel may result in loss of "wedging" action. If the wedge is hammered in carelessly it may damage the teeth. As the wedge is critical in the mesh holding action, any variation in the wedging action can cause loss of security.

Application 200223225 also describes a system somewhat similar to that described above except that complicated teeth are not used. Instead, the security of retainment of the mesh relies entirely upon a clamping friction force of the hammered in wedge.

Any variation if the frame profile or any damage to the frame or wedge can alter the friction fit and thus the security of the mesh.

There would be an advantage if it were possible to attach security mesh to a frame which did not requite complicated profiles, and which did not require a separate member e.g. a wedge) to secure the mesh.

Another known arrangement EP1026362) uses a frame with a channel. A mesh is inserted into the channel and it seems that the frame is then deformed or "crimped" to clamp the mesh. Specifically, the frame has a channel containing two edges O 3 The mesh is of a special type having rods embedded into a fabric. The fabric/rods is inserted into the channel see fig 2 of the EP specification] and deformed see fig Z 3] which causes a rod to be trapped behind an edge It is considered that a crimping process after insertion of the fabric is not very satisfactory as any variance in the crimping process can adversely affect the security of the fabric to the frame.

Flexible frame members containing two halves which can be opened up to allow a insect screen to be placed on the frame, and then closed to sandwich the screen, are IDalso known see UK 2310448], but are usually limited to flyscreens due to the rather S 10 flimsy design of the flexible frame.

Arrangements where the mesh is glued in place are also known 71855/98].

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

Object of the Invention.

It is an object of the invention to provide a security screen which may overcome at least one of the above-mentioned disadvantages or provide a useful or commercial choice.

In one form there is provided a security screen comprising a surround frame and a mesh, the surround frame containing a channel having a pair of opposed side walls and a rear interconnecting wall and an open front, a projection extending from one side wall and partially towards the other side wall to assist in securing the mesh in the channel, the security mesh having an edge region which is formed with a groove which is adapted to cooperate with the projection in the channel to assist in securing the mesh in the channel, and a cover retainer which extends about the edge region and over the groove, the cover retainer functioning inter alia to isolate the mesh from the channel, the construction and arrangement being that the cover retainer can be attached about the each region of the mesh and the mesh and cover retainer can then N 4 be inserted at least partially into the channel such that the projection in the channel and the groove in the mesh function to hold the mesh in the channel.

z In another form, the invention resides in a security screen comprising a surround frame, the frame containing a channel into which an edge of the mesh can be placed, the channel containing a projection to assist in securing the mesh in the channel, and a security mesh, the security mesh having an edge region which is formed with a groove Cc which is adapted to cooperate with the projection in the channel to assist in securing IDthe mesh in the channel, and a cover retainer which extends about the edge region and over the groove, the cover retainer functioning inter alia to isolate the mesh from the channel, the construction and arrangement being that the cover retainer can be attached about the each region of the mesh and the mesh and cover retainer can then be inserted at least partially into the channel such that the projection in the channel and the groove in the mesh function to hold the mesh in the channel.

In this way, the cover retainer can typically be slid over each edge of the mesh and the retainer/mesh can then be slid into the channel with the projection in the channel cooperating with the groove in the mesh to hold the mesh securely in the channel.

Thus, fasteners such as screws or rivets are not required. It is also not necessary to hammer or otherwise push some type of wedge block into the channel.

In a broad form, the invention resides in a security screen comprising a surround frame, the frame containing a channel into which an edge of the mesh can be placed, the channel containing a projection to assist in securing the mesh in the channel, and a security mesh, the security mesh having an edge region which is formed with a groove which is adapted to cooperate with the projection in the channel to assist in securing the mesh in the channel.

The security screen can be used for a window or a door. For instance, the security screen may comprise a sliding screen door, a sliding window, or may comprise a fixed screen fitted to the outside of an ordinary glass sliding window. The security screen can also be used on louvre windows and the like. It is also considered that the security screen can be used on any other type of opening that would benefit from a security screen.

O

Z The security screen can be of any suitable shape or size. If used in a window or a door, it is considered that the screen will be substantially rectangular and will have a length of between 0.5-3 m and a height of between 0.5-3 m. Of course, this can vary to suit and it is not considered that the invention should be limited only to these described sizes.

ID The surround frame can be made of any suitable material and the material will typically comprise extruded aluminium, plastic, steel, composite materials and the like. In most cases, the surround frame will be made of extruded aluminium. The frame may be made of lengths of product that are attached together (typically at the corners). Any type of attachment means can be used to assemble the various lengths together. These attachments may comprise rivets, screws, spot welds, corner stakes and the like and it is not considered that the invention should be limited to any particular way by which the frame is assembled.

The frame will typically contain a channel into which an edge of the mesh can be positioned. As it is desirable to have the mesh attached as securely as possible, it is considered desirable that the channel extends substantially about the frame. The channel will typically be a continuous channel although there may be some circumstances where a discontinuous channel may present some advantages. The channel will also typically be substantially U-shaped in cross-section although other cross-sections may also be suitable such as V shaped or other shapes. It is envisaged that the channel will contain a pair of spaced apart sidewalls, an inner wall (which can also be called a back wall or rear wall) and an open or substantially open front, to allow the mesh to be positioned in the channel. The spacing between the sidewalls will depend on the thickness of the mesh, the thickness of the cover retainer and the like, however it is considered that the spacing will typically be between 5-50 mm.

The "depth" of the channel (that is the distance between the front and the inner wall) can also vary to suit, and it is considered that a suitable depth will be between 5-50 mm.

N 6 A number of channels may be provided and these may be placed in a side-by-side and substantially parallel relationship if desired.

The channel, or each channel, or at least a portion of a channel contains a projection to assist in securing the mesh in the channel. The projection may comprise a rib which extends from at least one side wall and into the channel. The rib will typically extend less than 50% across the channel to provide sufficient space for the mesh etc. The rib Cc may comprise a continuous rib which can be extruded with the channel to maximise IDthe security of the attachment of the mesh into the channel. However, the rib may also comprise a plurality of separate ribs which will typically be in alignment. If desired, a plurality of spaced apart ribs may be provided in the channel to improve the attachment of the mesh to the channel. It is preferred that the surround frame has a continuous channel extending about the frame and facing inwardly and that the channel has a continuous rib. The projection may alternatively comprise a plurality of separate members (for instance fasteners) that can be drilled through the, or each, side wall to present the projection inside the channel. However, it is considered that this variance would be nuch more time-consuming than simply forming the rib with the channel. The projection may extend into the channel substantially at right angles to the side wall. Alternatively, the projection may extend into the channel at an angle.

Thus, the projection may "point" to the inner wall of the channel.

The projection may have various shapes. In a simple form, the projection comprises a rib which is substantially rectangular in cross-section. However, the projection may have other profiles if this can assist in attachment of the mesh. For instance, the projection may comprise an enlarged head portion, a barb, a "arrowhead" portion, a T section, a L section and the like, although it may then be necessary to alter the shape of the groove in the mesh and/or the cover retainer.

The security screen contains a security mesh. The mesh may comprise a woven mesh or perforated mesh. The woven mesh may be made of wires which are woven to form the mesh material. The wires may be made of steel, plastics, composite materials, coated wires, other types of metals and the like as long as the mesh can function as a security mesh. Alternatively, the mesh may comprise a sheet member which is IND 7 (perforated to provide a "mesh" type look. The mesh may also comprise elongate members that can be arranged in a "mesh or grid" type arrangement and attached Z together such as by spot welding, adhesive, fasteners and the like.

Typically, the security mesh will be somewhat flexible and therefore may need to be "stretched" into the frame to make the mesh reasonably taut. However, the mesh may also be reasonably rigid a thin steel or other metal perforated sheet).

N The mesh openings may have various sizes and shapes depending on the various factors but the openings should be small enough to prevent intrusion. It may be beneficial to make the openings sufficiently small such that the mesh can also function as an insect screen.

The shape and size of the mesh will depend on the shape and size of the surround frame. As the surround frame will typically be rectangular, the mesh will also typically be rectangular.

The mesh can have any suitable thickness which will depend inter alia on the degree of security required and the material from which the mesh is made. It is considered that the mesh will typically have a thickness of between 0.5-5 mm.

The mesh will have a peripheral edge which can be seen as the "edge region". If the mesh is rectangular, the peripheral edge will comprise four edges which are substantially at right angles to each other. Of course, this can vary. The edge region of the mesh is formed with a groove or something similar to assist in attachments of the mesh into the channel. The groove may comprise a pressing in the edge of the mesh. The shape and size of the groove will depend inter alia on the shape and size of the projection in the channel. Thus, if the projection in the channel is a simple rectangular cross-section, the groove may also have a substantially complimentary cross-section.

The mesh may contain a plurality of grooves which may be placed in a side-by-side relationship particularly if the channel contains a plurality of similar projections. The INO 8 Sgrooves may be on the same side or opposite sides of the mesh. However, in a simple form of the invention, the mesh will contain a single groove in the edge region.

z The groove will typically extend entirely about the edge region to maximise the security of attachment between the mesh and the surround frame, although there may be circumstances where the groove will be discontinuous. Unless the context requires otherwise, the term "groove" is not meant to be construed to narrowly and is meant to include any recess or depression which can cooperate in some way with the projection

\O

in the channel.

The security screen may contain a cover retainer. The cover retainer will typically extend over the edge region of the mesh and can also be positioned in the channel of the surround frame. The cover retainer can function, inter alia, as an isolator between the possibly different materials from which the mesh is made and from which the channel is made, and this can prevent corrosion caused by dissimilar metals coming into contact. However, the item can also function to assist in the attachment and the retention of the mesh inside the channel. The cover retainer is typically made of a non-metallic material and a suitable material will be plastics, rubbers, composite materials and the like. The cover retainer can be profiled to fit about the edge region of the mesh and about the projection in the channel of the surround frame.

Alternatively, the cover retainer can be made of reasonably flexible material such that it can adopt the profile.

In another form, there is provided a method to manufacture a security screen comprising a surround frame and a security mesh, the method comprising, providing surround frame members which are elongate and which have opposed ends at least one of which is open, and which have a longitudinal channel having a pair of opposed side walls and a rear interconnecting wall and an open front, a projection in the channel to assist in securing the mesh in the channel, the security mesh having an edge region which is sufficiently rigid to contain a groove in the edge region and which is adapted to cooperate with the projection in the channel to assist in securing the mesh in the channel, and a cover retainer which extends about the edge region and over the groove, the cover retainer functioning inter alia to isolate the mesh from the channel, O 9 ,Ic the construction and arrangement being that the cover retainer can be attached about the each region of the mesh and the mesh and cover retainer can then be inserted at 0 Z least partially into the channel only through the open end of the frame member such that the projection in the channel and the groove in the mesh function to hold the mesh in the channel.

Brief Description of the Drawings.

O An embodiment of the invention will be described with reference to the following 10 drawings in which:.

Figure 1. Illustrates a cross-section of the security screen.

Best Mode.

Referring to figure 1, there is illustrated a cross-section of the security screen and which basically comprises a surround frame 10, a channel 11 in the surround frame, a mesh 12, and a cover retainer 13. Surround frame 10, in the particular embodiment, is made of extruded metal (typically aluminium) and contains a substantially U-shaped channel 11, which comprises a pair of spaced apart sidewalls 14 which are parallel to each other and which are interconnected by an inner wall 15. The sidewalls are spaced apart by distance of between 5-20 mm although this can vary to suit.

In the particular embodiment, one of the sidewalls contains a projection 16.

Projection 16 comprises a simple continuous rib which is substantially rectangular in cross-section and which extends substantially at right angles from the side wall and less than halfway into the channel.

Mesh 12 can be a woven or perforated mesh and has an edge region which is positioned e.g. by sliding) into channel 11. The edge region will typically comprise the peripheral edge together with about 5-30 mm of mesh material spaced inwardly from the peripheral edge. The edge region has a groove 17 pressed into it, and the groove extends typically between 3-20 mm from the peripheral edge of the mesh.

Extending about the edge region is a cover retainer 13. The cover retainer 13 is non Z metallic and functions as an isolator and a retaining aid. Retainer 13 has a profile that _allows it to be pressed over the edge region of the mesh 12 and also about projection 16. Retainer 13 also has an edge 18 which functions to at least partially seal the otherwise open end of channel 11.

In use, the cover retainer 13 is clipped onto the edge of the mesh or is slid onto the N edge of the mesh. This can then be slid into channel 11 in such a way that projection S 10 16 cooperate with groove 17 which means that the mesh cannot be pulled out of the channel through the otherwise open end. The surround frame pieces can then be attached together which will prevent the mesh from sliding out of the surround frame and results in the mesh being securely held within the surround frame.

Throughout the specification and the claims (if present), unless the context requires otherwise, the term "comprise", or variations such as "comprises" or "comprising", will be understood to apply the inclusion of the stated integer or group of integers but not the exclusion of any other integer or group of integers.

Throughout the specification and claims (if present), unless the context requires otherwise, the term "substantially" or "about" will be understood to not be limited to the value for the range qualified by the terms.

It should be appreciated that various other changes and modifications can be made to any embodiment described without departing from the spirit and scope of the invention.

Claims (13)

1. 2. The screen of claim 1, wherein the surround frame comprises opposed ends, and the mesh and cover retainer can only be inserted into the channel by sliding the mesh and cover retainer through an opposed end.
2. 3. The screen of claim 1 or claim 2, wherein the end region of the mesh is sufficiently rigid to enable the groove to be formed in the mesh.
3. 4. The screen as claimed in any one of the previous claims, wherein the surround frame comprises separate frame members which are attached to each other after the mesh has been attached, whereby the opposed ends of the frame members are closed off and the mesh is trapped in the frame members. The screen as claimed in any one of the previous claims, wherein the spacing between the side is between 5-50 mm.
4. 6. The screen as claimed in any one of the previous claims, wherein the depth of the channel (that is the distance between the front and the rear wall) is between 5-50 mm. ND 12 O
5. 7. The screen as claimed in any one of the previous claims, wherein a number of channels are provided in a side-by-side and substantially parallel O Z relationship.
6. 8. The screen as claimed in any one of the previous claims, wherein the projection is a rib which extends less than midway across the channel to provide sufficient space for the mesh.
7. 9. The screen as claimed in claim 8, wherein a plurality of spaced apart ribs is provided in the channel to improve the attachment of the mesh to the channel. The screen as claimed in any one of the previous claims, wherein the projection comprises a rib which is substantially rectangular in cross-section.
8. 11. The screen as claimed in any one of the previous claims, wherein the mesh is a security mesh.
9. 12. The screen as claimed in any one of the previous claims, the mesh is a woven mesh of metal wires.
10. 13. The screen as claimed in any one of the previous claims, wherein the cover retainer functions as an isolator between the different materials from which the mesh is made and from which the channel is made to prevent corrosion caused by dissimilar metals coming into contact.
11. 14. The screen as claimed in any one of the previous claims, wherein the cover retainer functions to assist in the attachment and the retention of the mesh inside the channel.
12. 15. The screen as claimed in any one of the previous claims, wherein the cover retainer is profiled to fit about the edge region of the mesh and about the projection in the channel of the surround frame. IND 13
13. 16. A security screen substantially as hereinbefore described with reference to the figures. z S17. A method to manufacture a security screen comprising a surround frame and a security mesh, the method comprising, providing surround frame members which are elongate and which have opposed ends at least one of which is open, and which have a longitudinal channel having a pair of opposed side walls and a rear interconnecting wall and an open front, a projection in the channel to assist in IND securing the mesh in the channel, the security mesh having an edge region which is sufficiently rigid to contain a groove in the edge region and which is adapted to cooperate with the projection in the channel to assist in securing the mesh in the channel, and a cover retainer which extends about the edge region and over the groove, the cover retainer functioning inter alia to isolate the mesh from the channel, the construction and arrangement being that the cover retainer can be attached about the each region of the mesh and the mesh and cover retainer can then be inserted at least partially into the channel only through the open end of the frame member such that the projection in the channel and the groove in the mesh function to hold the mesh in the channel.