A SECURITY SCREEN FRAME

TECHNICAL FIELD

The present invention generally relates to security screens.

BACKGROUND

The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

Security screens are fitted to windows and doors to impede the unauthorized entry of intruders into buildings. Typically, a security screen includes a frame to which a mesh sheet is fitted.

Australian patent no. 736536 and Australian patent application no. 2006202825 both disclose security screens having frames including a number of extruded frame portions. Each elongate frame portion defines a pair of opposite jaws between which the mesh screen sheet can be received and retained. In practice, the screen sheet invariably becomes worn and needs to be replaced, but can be difficult to remove from the jaws.

Some security screens include metallic retaining pins which extend through both the jaws and the metal screen sheet held there-between. Undesirably, this arrangement can result in exacerbated corrosion of the screen sheet about the pins within the jaws.

Embodiments of the present invention to provide a frame which facilitates removal of the screen sheet.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, there is provided a frame for a security screen, the frame including two frame members which can be releasably interconnected to define a channel in which a screen sheet of the security screen can be received, the frame members defining formations that enable the members to pivot relative to each other.

The formations may include both a recess defined by a first one of the members and an arm, defined by the other second member, terminating in an bulbous head for being received in the recess. The arm may be resilient and bent to form a compression spring that facilitates maintaining interconnection of the members during assembly of the frame. The arm may define a groove in which a tongue of the first member can be received to facilitate locating the members together.

The frame members may further define other formations that enable the members to be releasably caught together upon being pivoted relative to each other. The other formations may include a pair of complementary heads, the heads defining mitred surfaces which can slide over each other and ledges for catching together.

Each of the members may define a retention arm, in turn, defining a set of serrated retention teeth. Each of the members may be elongate metal extrusions. One of the retention arms may be bent to facilitate clamping of a retainer means between the arms.

According to another aspect of the present invention, there is provided a portion of a frame for a security screen, the portion including two frame members which can be releasably interconnected to define a channel in which a screen sheet of the security screen can be received, the frame members defining formations that enable the members to pivot relative to each other.

According to another aspect of the present invention, there is provided a security screen, the security screen including: two frame members which can be releasably interconnected to define a channel; retainer means for being received in the channel; and a screen sheet for being retained within the channel by the retainer means.

The retainer means may be formed from resilient material including, for example, rubber. The retainer means may define a pair of opposite heads. Each head may define a mitred surface and a ledge. The retainer means may include a pair of adhesive strips.

The screen sheet may be formed of meshed or latticed material. The material may be fly screen material, for example.

According to another aspect of the present invention, there is provided a method for assembling a security screen, the method including the steps of: receiving a screen sheet within retainer means; and interconnecting two frame members to clamp the retainer means therebetween.

The step of interconnecting may involve the steps of: pivoting the frame members relative to each other; and catching the frame members together.

According to one aspect of the present invention, there is provided a frame for a security screen, the frame including two frame members which can be releasably interconnected to define a channel in which a screen sheet of the security screen can be received, the frame members defining formations that enable the members to be releasably caught together, wherein a tool can be inserted between one of the members and the screen sheet and engage with one of the formations so that the frame members can be released.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

Figure 1 is a sectional perspective view of a security screen in accordance with an embodiment of the present invention;

Figure 2 is a side sectional view of an unassembled frame portion of the security screen of Figure 1 ;

Figure 3 is a side sectional view of the assembled security screen of Figure 1 ; and

Figure 4 is a side sectional view of a frame portion in accordance with another embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

According to an embodiment of the present invention, there is provided a security screen 2 as shown in Figure 1. The security screen 2 includes a rectangular frame 4 which, in turn, includes four elongate frame portions that can interconnect at their ends. Each frame portion includes an outer frame member 6 and an inner frame member 8. The extruded aluminium frame members 6, 8 can be releasably interconnected to define a frame channel. The security screen 2 further includes a resilient rubber retainer 10 for being received in the frame channel. The retainer 10 can define a retainer channel in which a mesh sheet 12 is received and serves to retain the mesh sheet 12 within the frame channel. A detailed description of the security screen 2 is provided below.

Turning to Figure 2, the frame members 6, 8 define pivoting formations that enable the frame members 6,8 to be pivoted relative to each other. In particular, the pivoting formations include a concave recess 13 defined by the outer frame member 6, and a bent arm 14 of the inner frame member 8 that terminates in an bulbous head 16. The head 16 is received in the arcuate recess 13 and can rotate about an axis therein. The bent arm 14 defines a groove 18 in which a tongue 20 of the outer frame member 6 can be received to facilitate locating the frame members 6,8 together during assembly of the security screen 2.

The frame members 6,8 further define catch formations that enable the members 6,8 to be releasably caught together upon being pivoted relative to each other. In particular, the catch formations include a pair of complementary heads 22a, b of respective catches 24a, b, the heads 22a, b defining respective mitred surfaces 26a,b which can slide over each other and respective ledges 28a, b for catching together.

The frame members 6,8 define respective retention arms 30a,b, in turn, defining respective sets of inner serrated teeth 32a,b. The serrated teeth

32a,b are oriented to facilitate insertion of the retainer 10 into the frame channel whilst impeding its removal. The outer frame member 6 includes a bolster 34 for interconnecting the base of catch 24b with the outer end of retention arm 30b so that the arm 30b is well supported. In contrast, the free end of retention arm 30a is not supported which yields some compliance of that arm 30a.

Opposite the retention arm 30b, the outer frame member 6 includes a tubular support 36 which can be fastened to a door or window frame. The tubular support 36 may define outer furrows 38 to locate screw tips during fastening.

The retainer 10 is integrally formed from a resilient rubber strip and can be folded over itself as shown in Figure 3. The retainer 10 defines a pair of

opposite heads 40a, b. Each head 40 defines a mitred surface and a ledge for abutting against the frame 4.

As can best be seen in Figure 1 , the mesh sheet 12 is formed from latticed material, in turn, including two sets of parallel elements which are orthogonally arranged.

A method for assembling the security screen 2 is now described.

Initially, the retainer 10 is folded over itself to define the retainer channel in which the mesh sheet 12 is received (see Figure 3).

Next, the two frame members 6,8 are interconnected to clamp the retainer 10 there-between as shown in Figure 3. Elaborating further with reference to Figure 2, tongue 20 of the outer frame member 6 is first received within the groove 18 defined by the bent arm 14. The retainer 10 wrapped around an edge of the mesh sheet 12 is then rested upon the retention arm 30b of static outer frame member 6.

In turn, the inner frame member 8 is rotated downwardly about head 16 within recess 13. The mitred surfaces 26 of catches 24 slide over each other, as resilient catch 24a momentarily bends inwardly whilst catch 24b remains substantially static. Furthermore, bent arm 14 compresses so that the groove 18 narrows. Once the heads 22 of the catches 24 pass each other, catch 24a straightens once again as shown in Figure 3.

The retention arms 30a, 30b clamp the retainer 10 within the frame channel and, in turn, the retainer 10 clamps the mesh screen within its confines. The ledges 28 of the catches 24 are caught together and prevent the outer ends of the retention arms 30 from separating. Furthermore, the bent arm 14 is held in compression, and facilitates maintaining interconnection of the frame members 6,8 by forcing catch 24a toward the mesh screen 12 to ensure that the ledges 28 remain caught. The serrated teeth 32 embed themselves in the retainer 10 to impede axial removal thereof.

The security screen 2 is held together without the need for metal pins that could potentially extend through the retention arms 30, retainer 10 and mesh screen 12. The removal of a need for these pins advantageously reduces the assembly time and complexity of the security screen 2. Furthermore, the presence of the pins could otherwise result in increased corrosion of the mesh screen 12 within the frame channel.

The frame members 6,8 can be readily disconnected when replacing the mesh screen 12. Referring to Figure 3, the tip of a screw driver can be slid between the roof of the retainer 10 and the underside of the retention arm

30a. The screw driver tip can press against the stem of catch 24a, further compressing bent arm 14, and thereby disengage the caught ledges 28 of the catches 24. In turn, the screw driver can then be pivoted about retainer head 40a to separate the retention arms 30. Once the retention arms 30 are separated as shown in Figure 2, the retainer 10 and mesh screen 12 can be freely removed from the frame 4.

A person skilled in the art will appreciate that many embodiments and variations can be made without departing from the ambit of the present invention.

In the preferred embodiment, the mesh screen 12 was received within a retainer 10, and therefore within the frame channel in which the retainer 10 was received. In an alternative embodiment, the security screen 2 may not include a retainer so that the mesh screen 12 is received directly into the frame channel. In this manner, the arms 30 would engage directly with the mesh screen 12. Pins could potentially extend through the retention arms 30 and mesh screen 12 to improve the durability of the assembled security screen 2.

In the preferred embodiment, retention arm 30a was substantially straight. In an alternative embodiment shown in Figure 4, retention arm 30a may bend inwardly toward its free end to improve clamping of the retainer 10 between

the arms 30. In addition, retention arm 30b may be solid for improved strength.

In the preferred embodiment, the mesh screen 12 was formed from durable latticed material. In an alternative embodiment, the material may be less durable and could be fly screen material, for example.

In one embodiment, the retainer 10 may have adhesive applied to its opposite faces. In this manner, the inner face of the retainer 10 adheres to the mesh screen 12 whilst the outer face of the retainer 10 adheres to the inner faces of the retention arms 30 bearing the serrated teeth 32.

In another embodiment, the retainer 10 may instead include two adhesive strips (of tape) each having adhesive applied to both contact faces. One adhesive strip is adhered between the upper retention arm 30a and the top face of the mesh screen 12 whilst the other adhesive strip is adhered between the lower retention arm 30b and the bottom face of the mesh screen 12. The adhesive improves the retention of the mesh screen 12 within the retention arms 30.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art.