AU2021102984A4

AU2021102984A4 - Method and apparatus for retaining a sheet of planar material

Info

Publication number: AU2021102984A4
Application number: AU2021102984A
Authority: AU
Inventors: Shannon Crowe
Original assignee: Amden Eng Pty Ltd
Current assignee: Amden Engineering Pty Ltd
Priority date: 2021-05-31
Filing date: 2021-05-31
Publication date: 2021-07-22
Anticipated expiration: 2029-05-31

Abstract

There is propose a retention means for a sheet of planar material, including, a frame, a screw clamp device and an elongate retention member. The frame delineates a void, whereby the sheet of planar material extends substantially over the 5 void and is attachable to the frame. The screw clamp device comprises a plurality of fixing members or fasteners, wherein the screw clamp device engages an edge of the sheet of planar material, and the elongate retention member is used to tension the sheet of planar material, to inhibit it from detachment from the frame. The apparatus reduces the number of fasteners required by using a screw clamp and 10 wedge member in combination. 2/7 10 14 .L 32 26 16 28 24 28 38 34 36 34 30 40 12 12 Figure 3

Description

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METHOD AND APPARATUS FOR RETAINING A SHEET OF PLANAR MATERIAL FIELD OF THE INVENTION

The present invention relates to an apparatus and method for fixing a sheet of planar material to a frame. In one particular aspect there is proposed a mesh retention system for a security screen door or window.

BACKGROUND OF THE INVENTION

There are various systems suggested and disclosed in the prior art for securing the mesh of a security screen. Commonly, a stainless-steel mesh is fixedly attached to an aluminium frame to inhibit detachment therefrom. The security screen can be placed across a doorway or window to control or restrict entry.

Typically, a screw clamp system is used that acts to clamp the mesh locally around the head of a screw. The screw is attached to the frame of the security screen or an intermediate plastic block attached to the frame. In some systems a clamping block may be used. This means that the mesh which spans in between each screw is unrestrained and not clamped flat. Accordingly, when the mesh in the door or window is impacted, the energy is transferred through the mesh directly to the individual screw points. This has the potential to tear the screws through the mesh if an insufficient number of screws have been used.

To avoid this issue, some installers will use more screws than are typically necessary, to thereby share the load under high impact situations. This increases the time taken to install or construct the window or door.

One such system is disclosed in Australian Patent No. 2016203238 entitled A Frame Assembly Including Screws to Jim Reid, which teaches a frame assembly for securing a security screen. The assembly is held together by screws that pass through an insulating clamp, the security screen and an insulating block.

Another system in the published prior art is disclosed in Intentional Application No. PCT/AU95/00337 to Pepperell et al. The PCT application discloses an intruder resistant screen, including a plurality of clamping members that cooperate with respective fasteners to thereby clamp the mesh to a frame.

There are other systems disclosed in the prior art that include a wedge pressure system, however these can be displaced in high impact situations. To the knowledge of the Applicant, such wedge types systems have not to date been used in conjunction with a screw clamp system. There is furthermore no suggestion in the prior art to combine the two different types of securing systems to overcome some of the problems with the existing securing screens.

Some of the systems currently available in the market utilise screw clamp systems, wherein the screw pass through the mesh and are secured into the aluminium frame. An issue with screwing through stainless steel into aluminium is galvanic corrosion due to dissimilar metal contact.

It should be appreciated that any discussion of the prior art throughout the specification is included solely for the purpose of providing a context for the present invention and should in no way be considered as an admission that such prior art was widely known or formed part of the common general knowledge in the field as it existed before the priority date of the application.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide for a fixing system for the edge of a sheet of planar material, such as but not limited to the mesh of a security screen. Further objects of the present invention are to overcome at least some of the aforementioned problems, or at least provide the public with a useful alternative. The foregoing objects should not necessarily be considered as cumulative and various aspects of the invention may fulfil one or more of the above objects.

In one aspect of the invention, but not necessarily the broadest or only aspect, there is proposed a security screen apparatus, including: a frame delineating an opening; a portion of security mesh attachable to the frame and extending over the opening; a screw clamp device comprising a plurality of fixing members or fasteners; and an elongate retention member for tensioning the portion of security mesh, wherein the security mesh is inhibited from detachment from the frame under high impact conditions.

The reader should appreciate that the elongate retention member applies a secondary continuous pressure along an edge of the mesh. The elongate retention member may be a wedge or wedges or may be an attachable screw cover which applies the secondary continuous pressure to the mesh.

In one form the elongate retention member is an elongate wedge member.

The reader should appreciate that the proposed apparatus incorporates the concept of using a wedge pressure system, in combination with a screw clamp system.

The elongate wedge member offers continuous pressure along the length of the channel to retain the mesh. While the screw clamp device offers additional clamping pressure (although only locally), as well as acting as a mechanical stop by pinning through the mesh.

By combining both methods, the number of screws required to retain the mesh is reduced, which speeds up installation time, while improving the integrity of the mesh due to less holes being drilled into it.

In one embodiment the screw clamp device includes a rigid plastic insulator/plastic bar that is coupled to the frame and into which the screws engage, wherein the head of a respective screw abut the mesh. This avoids the issues associate with galvanic corrosion due to contact between the stainless steel of the screws/mesh and aluminium of the frame.

Alternatively, the screw clamp device may be designed to be screwed directly into the aluminium frame as per a typical system.

The frame is preferably an aluminium extrusion that can be cut to the required length. The sides of the frame can be joined, to thereby form a four sided polygon with four right angle corners. Conventional joining brackets can be used to join the sides of the frame.

The continuous clamp pressure along the edge of the mesh results in a flatter installation which reduces the amount of bellowing that can occur when non continuous clamping is used.

In the areas where screws are not present, the action of driving in a wedge or attaching the screw cover pulls the mesh with it creating tension on the mesh, enabling a taught mesh installation which is typically not possible in conventional screw clamp systems.

Furthermore, the need for fewer screws maintains better integrity of the mesh, as fewer strands are broken when the mesh is drilled. As the skilled addressee will appreciate this means that more strands are available to disperse the energy of an impact.

In one form the elongate wedge member comprises two parts, wherein a rubberised plastic strip with serrations is inserted first, followed by a rigid plastic or aluminium wedge, which compresses the rubberised plastic strip into the mesh thereby creating a strong continuous grip.

In another form the elongate wedge member comprises a single piece wedge only with no rubberised plastic strip.

The wedge may extend up to cover the heads of the screws for aesthetic purposes.

In another aspect of the invention there is proposed a method of securing the edge of a mesh of a security screen, including the steps of: providing a security screen apparatus, including a frame, a portion of security mesh, a screw clamp device having a plurality of fasteners, and an elongate retention member; constructing the frame to correspond to the dimensions of a doorway of window; positioning the portion of security mesh over an opening formed by the frame; securing the security mesh to the frame using the plurality of fasteners of the screw clamp device; and attaching the elongate retention member to provide secondary pressure to thereby tension the portion of security mesh.

In still another aspect of the invention, there is proposed a retention means for a sheet of planar material, including: a frame delineating a void, whereby said sheet of planar material extending substantially over the void and being attachable to the frame; a screw clamp device comprising a plurality of fixing members or fasteners, wherein the screw clamp device engages an edge of said sheet of planar material; and an elongate retention member for tensioning said sheet of planar material, wherein the sheet of planar material is inhibited from detachment from the frame.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an implementation of the invention and, together with the description and claims, serve to explain the advantages and principles of the invention.

In the drawings,

Figure 1 is perspective view of the security screen apparatus of the present invention used on a doorway;

Figure 2 is an end view of a portion of a first embodiment of the security screen apparatus of Figure 1;

Figure 3 is a perspective view of a portion of the security screen apparatus of Figure 2;

Figure 4 is another perspective view of a portion of the security screen of Figure 2;

Figure 5 is an exploded view of the security screen apparatus of Figure 4;

Figure 6 is an end exploded view of the security screen apparatus of Figure 4;

Figure 7 is an end view of the frame of Figure 2 with the plastic bar of the screw clamp device attached;

Figure 8 is the end view of Figure 7 with the mesh in position;

Figure 9 is the end view of Figure 8 with the rubberised plastic strip in position;

Figure 10 is the end view of Figure 9 with a screw attached;

Figure 11 is the end view of Figure 10 with the rigid plastic or aluminium wedge in position;

Figure 12 is an end view of a second embodiment of the security screen apparatus, wherein the screws are screwed through an intermediate clamping member and into the aluminium frame followed by wedge;

Figure 13 is the end view of the security screen apparatus of Figure 2; and

Figure 14 is an end view of a third embodiment of the security screen apparatus, wherein the screws are screwed into a plastic strip followed by removable aluminium frame cover and pressure wedge.

DETAILED DESCRIPTION OF THE ILLUSTRATED AND EXEMPLIFIED EMBODIMENTS

Similar reference characters indicate corresponding parts throughout the drawings. Dimensions of certain parts shown in the drawings may have been modified and/or exaggerated for the purposes of clarity or illustration.

Referring to the drawings for a more detailed description, there is illustrated a security screen apparatus 10, demonstrating by way of examples, arrangements in which the principles of the present invention may be employed.

As illustrated in Figures 2 to 6, the security screen apparatus 10, includes a frame 12, a portion of security mesh 14, a screw clamp device 16 and an elongate retention member 18.

The security mesh 14 is attachable to the frame 12 to thereby secure an opening. As illustrated in Figure 1, the opening may be a doorway 20 in a building wall 22, alternatively the opening may be a window (not shown). The reader should appreciate that the present invention could be used to attach a sheet of material to a frame and used on openings other than windows or doors.

The screw clamp device 16 comprises a plurality of fixing members or fasteners in the form of screws, 24 which are screwed through the mesh 14 and into a plastic bar 26. The plastic bar 26 engages a correspondingly shaped slot or recess 28 in the frame 12, as illustrated in Figures 2 and 3.

As the reader will appreciate, the frame 12 forms a generally rectangular shape, with each side having a respective screw clamp device 16 and elongate retention member 18. In this way the elongate retention members 18 apply a secondary pressure circumferentially around the edge of the mesh 14 to thereby hold it taut with the frame 12.

In the present embodiment, the elongate retention member 18 comprises a rubberised plastic strip 30 with serrations and a rigid plastic or aluminium wedge 32.

The rigid plastic or aluminium wedge 32 compresses the rubberised plastic strip 30 into the mesh 14 creating a strong continuous grip along the edge of the mesh 14 to thereby provide tensioning thereof.

As illustrated in Figures 2, 3 and 6, the rubberised plastic strip 30 of the elongate retention members 18 includes serrations 34 that form a gripping face for contact with the mesh 14. The gripping face may alternatively be a roughened surface or a resiliently deformable surface that acts to grip the mesh therealong. The rigid plastic or aluminium wedge 32 of the elongate retention members 18 also includes serrations or rows of teeth 36, as illustrated in Figure 5. The serrations or teeth 36 are configured to cooperate with correspondingly shaped serrations or rows of teeth 38 in an upstand 40 of the frame 12, as illustrated in Figures 3 and 6.

Generally, the elongate retention member 18 may be referred to collectively as a wedge member, which applies the secondary pressure along the edge of the mesh 14. Although envisaged to be a single continuous wedge along each edge, multiple wedge members could be used to provide pressure around the circumferential edge of the mesh, where it affixes to the frame.

As shown in Figures, 3, 12 and 13, the wedges 32 or 46 may extend up to cover the heads of the screws 24 for aesthetic purposes and to inhibit unauthorised tampering.

The reader should appreciate that the elongate wedge member 18 offers continuous pressure along the length of the channel to retain the mesh 14 and the screw clamp device 16 offers additional clamping pressure or backup where an impact is sufficiently strong to overcome the grip strength of the elongate wedge member 18.

On a large impact, once the grip pressure of the elongate wedge member 18 is overcome and the mesh 14 starts to slip, the mesh 14 must then overcome the grip pressure applied by the screws 24 of the screw clamp device 16, then finally the mesh 14 must tear past the screws 24 to slip out of the retention system.

The plastic bar 26 in one form is a rigid plastic insulator that is coupled to the frame 12. This avoids the issues associate with galvanic corrosion due to contact between the stainless steel of the screws 24/mesh 14, and the aluminium of the frame 12.

The continuous clamp pressure along the edge of the mesh 14 results in a flatter installation which reduces the amount of bellowing which can occur when non continuous clamping is used.

In the areas where screws are not present, the action of driving in a wedge or attaching the screw cover pulls the mesh 14 taut thereby tensioning the mesh, which results in a tight mesh installation, which is not possible on a typical screw clamp system.

Furthermore, the need for fewer screws results in greater integrity of the mesh 14, since fewer strands are broken when the mesh is drilled. As the skilled addressee will appreciate, this means that more strands are available to disperse the energy of an impact.

As illustrated in Figures 7 to 11, there is also envisaged a method of securing the edge of a mesh 14 of a security screen 10. The reader will appreciate that only one side of the frame is illustrated, but the same process will be applied to all sides of the frame 12 to attached the mesh 14 therebetween.

Figure 7 illustrates the plastic bar 26 of the screw clamp device 16 attached within the correspondingly shaped extruded frame 12. Figure 8 illustrates the security mesh 14 in position adjacent the plastic bar 26. As illustrated in Figure 9 the rubberised plastic strip 30 is then placed in position, and the screws 24 are fixed through the mesh 14 and into the plastic bar 26, as illustrated in Figure 10, to thereby clamp the mesh 14 in place.

The final step involves the insertion of the rigid plastic or aluminium wedge 32 into position, as illustrated in Figure 11. The wedge 32 bears against the upstand 40 and compresses the rubberised plastic strip 30 into frictional abutment with the mesh 14, to thereby create a strong continuous grip along the edge of the mesh 14.

Figures 12 and 14 illustrate alternate configurations of the security screen apparatus 10, which can be compared to Figure 13, which illustrates the immediately preceding embodiment.

Figure 12 illustrates a second embodiment of the security screen apparatus 10, wherein the screws 24 are screwed through an intermediate clamping member 42 and into a part 44 of the aluminium frame 12. A single serrated elongate wedge

46 is then forced between the upstand 40 and the mesh 14. The elongate wedge 46 is also configured to conceal the heads of the screws 24.

Figure 14 illustrates a third embodiment of the security screen apparatus 10, wherein the screws 24 are screwed into a plastic strip 48 much like the embodiment of Figure 1. A removable aluminium frame cover 50, is then attached to the frame 12, whereafter an elongate pressure wedge 52 is forced between the upper end 54 of the cover 50 and the mesh 14. The removable aluminium frame cover 50 is configured to conceal the heads of the screws 24. The upper end 54 of the cover 50 and wedge 52 include cooperating teeth 56.

The reader should however appreciate that a present invention could also be considered to comprise a retention means for a sheet of planar material, wherein the sheet of planar material is attached to a frame using a screw clamp device comprising a plurality of fixing members or fasteners and an elongate retention member. Wherein the elongate retention member is configured to tensioning the sheet of planar material, wherein the sheet of planar material is inhibited from detachment from the frame.

The skilled addressee will now appreciate the advantages of the illustrated invention over the prior art. In one form the present invention provides a means for securing the mesh of a security screen or planar sheet of material. The use of both a screw clamp and wedge in combination, provides continuous clamping of the mesh along the entire perimeter using grip pressure provided by driving in the wedge. Only once the grip of the wedge pressure is overcome by an impact strong enough, will the screw clamp be required to inhibit separation between the frame and the mesh. Accordingly, in combination with a wedge, the quantity of screws required to be used is reduced, which result in a faster build time.

Various features of the invention have been particularly shown and described in connection with the exemplified embodiments of the invention, however it must be understood that these particular arrangements merely illustrate the invention and it is not limited thereto. Accordingly, the invention can include various modifications, which fall within the spirit and scope of the invention.

Claims

1. A security screen apparatus, including: a frame delineating an opening; a portion of security mesh attachable to the frame and extending over said opening; a screw clamp device comprising a plurality of fixing members or fasteners; and an elongate retention member for tensioning the portion of security mesh, wherein said security mesh is inhibited from detachment from said frame under high impact conditions.

2. The apparatus in accordance with the claim 1, wherein the elongate retention member is an elongate wedge member or members, the elongate wedge member or members comprises a rubberised plastic strip with serrations being insertable first into a recess in the frame, followed by a rigid plastic or aluminium wedge, which compresses the rubberised plastic strip into the mesh thereby creating a strong continuous grip.

3. The apparatus in accordance with the claim 1, wherein the screw clamp device includes a rigid plastic insulator being couplable to the frame, and into which the screws engage.

4. A method of securing the edge of a mesh of a security screen, including the steps of: providing a security screen apparatus, in accordance with any one of claims 1 to 4; constructing the frame to correspond to the dimensions of a doorway of window; positioning the portion of security mesh over an opening formed by the frame; securing the security mesh to the frame using the plurality of fasteners of the screw clamp device; and attaching the elongate retention member to provide secondary pressure to thereby tension the portion of security mesh.

5. A retention means for a sheet of planar material, including: a frame delineating a void, whereby said sheet of planar material extending substantially over the void and being attachable to the frame; a screw clamp device comprising a plurality of fixing members or fasteners, wherein the screw clamp device engages an edge of said sheet of planar material; and an elongate retention member for tensioning said sheet of planar material, wherein the sheet of planar material is inhibited from detachment from the frame.