Field of the invention

The present invention reJates to the provision of screens for the external areas of dwellings and the like and is related to our co-pending international patent application

PCT/AU2009/000057, Hied on 29 January 2009.

Background of the invention

Some homes have outdoor entertainment areas which accommodate a table and chairs, speakers for relaying music, fountains and the like. Home owners seek to maximize the use of such areas by excluding breezes and excessive sun by the provision of retractable screens. If the shielded area is to provide solar reduction while retaining a view then mesh is effective. If overall weatherproofiπg is desired then transparent plastic is the choice. In sunny latitudes, both are needed. However, whether the screens be of mesh (which allows the passage of some breeze through it) or of transparent plastic (which docs not allow the passage of breeze through it) there can be substantial wind-loading on the screens.

Summary of the invention

In one aspect, the present invention provides a head box assembly for the mounting therein of a screen or the like, which screen is rollable onto and off of a roller which:

is mountable within the head box assembly;

wherein the longitudinal axis of the roller is substantially parallel to the longitudinal axis of the head box assembly,

the head box assembly comprising a first cover and a second cover, each of which first and second covers:

extends in the longitudinal direction of the head box;

arc substantially identical in their cross-sectional shape.

It is preferred that:

each first and second cover has two longitudinally extending peripheral edge regions; and

one longitudinally extending peripheral edge region of the first cover is adapted to connect with one longitudinally extending edge region of the second cover. ft is preferred that, in each cover, the shape of one longitudinally extending peripheral edge region is substantially complementary to the shape of the other longitudinally extending peripheral edge region.

It is preferred that each of the first and second covers is substantially "L" shaped in cross section.

In another aspect, the present invention provides a cover for a head box assembly, which cover is adapted to function as the first cover or the second cover of a head box assembly as set out in any one of the preceding paragraphs of this summary.

In another aspect, lhe present invention provides a blowout reslriclor comprising a base which carries two upstanding flanges each of which flanges runs in the longitudinal direction of the blowout rcstrictor, each flange comprising:

a portion which stands substantially normal to the base; and

remote from the base, a portion which extends towards the other flange, the flanges thereby defining between them a channel for the receipt of an edge of the screen or the like.

In another aspect, the present invention provides a channel assembly comprising a base and a cover:

the base comprising a substantially planar portion, from which there extends: a first flange which extends from the planar portion at or adjacent a longitudinally-extending edge of the base portion, and

a second ^' flange which extends from the planar portion in the same direction as does the first flange, and which runs substantially parallel to the first flange;

the cover comprising a substantially planar portion, the substantially planar portion comprising:

a longitudinally-extending edge which has a profile which is substantially complementary to at least a portion of a void which is defined at or adjacent the edge of the first flange which is remote from the base; and a hook which has a profile which is substantially complementary to a; least a portion of a void which is defined at or adjacent the edge of the second flange which is remote from the base.

It will be seen that various embodiments of the present invention permit the production of head boxes which use two components which are of substantially identical cross-sectional shape, where previously it was necessary to use two components which had different cross-sectional shapes.

It will also be seen that various embodiments of the present invention inhibit the screen or mesh from blowing out under wind loading. Brief description of the drawings

Preferred embodiments of the invention are described with reference to the drawings in which:

figure 1 is an isometric view from the outside of a screen assembly according to a preferred embodiment of the present invention;

figure 2 is an isometric view from the inside of a screen assembly according to another preferred embodiment of the present invention;

figure 3 is an exploded isometric view of the screen assembly of figure 1 ;

figure 4 is a cross-sectional view of components of a head box of the screen assembly of figure 1;

figure 5 is a cross-sectional view of components of a side channel of the screen assembly of figure 1;

figure 6 is an isometric view of α blowout restrictor of the assembly of figure 1 ; figure 7 is an elevational view of the blowout restrictor of figure 6;

figure 8 is an elevational view of the blowout restrictor of figure 6; and figure 9 is another elevational view of the blowout restrictor of figure 6.

Description of preferred embodiments of the invention

Structure

Figure 1 illustrates a screen assembly 1 from a view point which would be outside the area which is shielded by the screen, as in a window for example. As is illustrated in figure 1 , a screen assembly 1 according to embodiments of the present invention comprises a head box assembly 3, a left side channel 5, a right side channel 6, and a bottom rail 7. The screen assembly 1 is adapted to receive, in the manner which is described below, a screen which is not illustrated in the drawings.

As is more particularly illustrated in figures 3 and 4 the head box assembly comprises front cover 17 and a rear cover 19 (again, considering the "front" and -"rear" of the screen assembly 1 when viewed from a view point which would be outside the area which is shielded by the screen). The head box assembly also comprises right hand end and left hand end cover plates 9 and 10 respectively, a driving eye 15, a gear box 21 , a roller lube 23, a pivot plate 29, an idler pin 31 and an R-clip 33.

The front cover 17 and the rear cover 19 have the same shape in cross-section, and when assembled in the head box assembly 3 can be considered as being mirror images of each other. A preferred form of manufacture of the front cover 17 and rear cover 19 is by extrusion from aluminium, aluminium alloy or plastics materials. The front cover 17 and rear cover 19 carry longitudinally-running screw bites 35. One peripheral edge of each of the from cover 17 and the rear cover 19 carries a projecting connection tongue 34. The other peripheral edge of each of the front and rear cover 17 and the rear cover 19 carries a connection groove 36 which is substantially complementary in cross-sectional shape to the cross-sectional shape of the connection tongue 34.

Each end plate 9 and 10 is a substantially flat sheet having a locating lab 41 projecting in a direction which is substantially normal to that sheet, substantially longitudinal to the body of the head box assembly 3. A number of screw holes 45 extend through each end plate 9 and 10 adjacent the periphery of the plate. A number of component mounting screw holes 47 extend through each end plate 9 and 10 in a region which is remote from the periphery of the end plate.

The periphery of each end plate 9 and 10 comprises a front peripheral portion 37, a rear peripheral portion 39 and a notch 43. Each front and rear peripheral portion 37 and 39 conforms substantially to the cross-sectional shape of the front cover 17 and the rear cover 19 of the head box assembly 3. The gear box 21 is mounted to the left hand end plate 10, or right hand end plate 9, with screws which pass through the component mounting screw holes 47 in that end plate. The pivot plate 29 is similarly mounted to the right hand end plate 9, or the left hand end plate 10, with screws which pass through the component mounting screw holes 47 in that end plate. The idler pin 31 extends from the right hand end, or left hand end, of the roller tube 23 and the other end of the roller tube 23 is adapted for coupling to the output shaft of the gear box 21. The driving eye 15 of the gear box 21 is adapted to project through an aperture 18 in the front cover 17 of the head box, on either end as required. Each of the side channels 5 and 6 comprises a side channel base 49, a channel cover 51 and at least two blowout rcstrictors 1 1. Each side channel base 49 is identical in cross section but when in use arc mounted as mirror images of each other. Each side channel base 49 comprises a planar portion 53 with an upstanding outer flange 54 and an upstanding inner flange 55. Each side channel 5 and 6 is adapted for mounting to a structure by screws or other suitable fasteners which pass through the outer flanges 53 or 54 (dependant on wheiher a face or reveal fix is required) into that structure.

The edge of the flange 54 which is remote from the planar base portion 53 carries an upper longitudinally-running lip 79 and a lower longitudinally-running Up 81. The lips 79 and 81 define a void between them. The edge of the flange 55 which is remote from the planar base portion 53 carries an upper, longitudinally-running projection 83 and a lower, longitudinally-running sill 85. The projection 83 and the sill 85 define a void between them. A longitudinally-extending edge 79 of the side channel cover 51 has a profile which is substantially complementary to at least a portion of the void which is defined between the lip 79 and the lip 81. A hook 89 depends from the side channel cover 51. The hook 89 has a profile which is substantially complementary to at least a portion of the void which is defined between the upper projection 83 and the lower sill 85.

Each blowout rcstrictor 1 1 comprises a base 57 which carries an upstanding left hand flange 59 and an upstanding right hand flange 61 each of which runs in the longitudinal direction of the restrictor 11. The upstanding left hand flange 59 carries a projecting portion 60 remote from the base 57. Similarly, the upstanding right hand flange 61 carries a projecting portion 62 remote from the base 57. The projecting portions 60 and 62 project towards each other. As is most clearly illustrated in the elevational view of figure 9, the opposed faces of flanges 59 and 61 and the opposed faces of projecting portions 60 and 62 are tapered of to define a lower notch 63 and an upper notch 65 in the regions between the two flanges 59 and 61. The upper ^' notch 65 is substantially triangular in clevational view and the lower notch 63 resembles a truncated triangle in elevation. Voids in the projecting parts 60 and 62 of flanges 59 and 61 respectively define apertures 69 and 70. The apertures 69 and 70 receive substantially L-shaped metal latch plates 74 and 75 respectively.

As is most clearly illustrated in figure 8, the shape of the flanges 59 and 61 results in there being a bore or channel 64 running in the longitudinal direction of the blowout rcstrictor 1 1. Each blowout rcstrictor 1 1 has mounting holes 67 passing through the base 57 to enable mounting by screws to the inner flange 55 of a side channel 5 or 6.

Two latch pins 71 are mounted within the bottom rail 7, one proximate each end of that bottom rail. The latch pins 71 are driven in unison by linkages which are not shown in the drawing and which arc in turn driven by rotation of the latch handle 73. When in the "thrown" position, each latch pin 1\ is adapted to enter a lower notch 63 in a blowout restrictor. Upwards tension in the screen which is attached to the bottom rail 7 tends to bias the rail upwards. The latch pins 71 which are carried by that rail arc thus biased upwards to bear against the latch plates 74 and 75. The bottom rail 7, and the lower edge of the screen which is retained within that bottom rail, arc thus latched in a fixed position.

Figure 2 illustrates a screen assembly 1 according to another preferred embodiment of the invention, from a view point which would be inside the area which is shielded by the screen. The embodiment of figure 2 differs from the embodiment of figure 1 in that the driving eye 15 of the gear box 21 is adapted to project through an aperture 18 in the rear cover 19 of the head box. Assembly

When installing a screen assembly 1 in place, the installer would first assemble the two end caps onto either end of the rear head box cover, then assemble the gear box 21 and pivot pin assemblies 29 in place, situation of both determined by either left hand or right hand gear box operation. The head box would then be offered into position and mounted in the required position by suitable means such as by mounting screws which pass through end caps 9 and 10 (for reveal fixing), or through the rear head box cover 19 (for face fixing) into the substrate. The roller tube 23 is mounted between the gear box 21 and the pivot plate 29 by inserting the idler pin 31 into the pivot plate 29, and retaining it in place by inserting the R-dip 33. The front cover 17 of the head box is then mounted in place. The fabric of the screen 77 is both retained at one end on the roller tube 23 and retained at its other end within the bottom rail 7. Opposite side edges of the screen 77 are retained within the channels 64 in the blowout restrictors 1 1 as is illustrated in figure 8. The left side channel assembly 5 and the right side channel assembly 6 arc mounted below the head box assembly 3 with the bottom rail located at each of its ends within the relevant side channel assembly. In assembly of the side channels 5 and 6, the peripheral hook 87 is on the cover 51 is inserted in the void which is defined between the upper lip 79 and the lower lip 81. The side channel .cover 51 is then rotated about the hook 79 in the manner of a hinge so that the lower hook 89 is rotated into the void which is defined between projection 83 and the sill 85. Resilience of the flange 55 serves to provide a snap-fit of the hook 89 into that void.

While the present invention has been described with reference to a few specific embodiments, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims. Throughout this specification, the words "comprise", "comprising", and corresponding parts of speech are to be taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. In the claims, each dependent claim is to be read as being within the scope of its parent claim or claims, in the sense that a dependent claim is not to be interpreted as infringed unless its parent claims arc also infringed.