RETRACTABLE SCREEN ASSEMBLY

A screen retraction mechanism for a retractable screen assembly, the screen retraction mechanism comprising: a roller housing; a roller spinably mounted within the roller housing and for rolling a screen material sheet thereon; a torsion spring coupled to the roller for rotationally biasing the roller; and a tension adjuster coupled to an end of the torsion spring and configured to move in and out of engagement with the roller housing, wherein the tension adjuster is spinnable to selectably tension the torsion spring when out of engagement with the roller housing.

TECHNICAL FIELD

The present disclosure relates to retractable screen assemblies for architectural openings, and particularly but not exclusively to screen retraction mechanisms for retractable screen assemblies for doors and windows. The present disclosure also relates to a latch mechanism for a retractable screen assembly for architectural openings, and particularly but not exclusively to latch mechanisms for retractable screen assemblies for doors and windows.

BACKGROUND

Any references to methods, apparatus or documents of the prior art are not to be taken as constituting any evidence or admission that they formed, or form part of the common general knowledge.

Retractable screens that can be extended across an architectural opening and rolled away when retracted may allow an uninterrupted view and passage when retracted. Retractable screens may be installed across any suitable architectural opening including but not limited to window, doors, and between supports in outdoor areas such as pergolas, gazebos and the like, and may comprise insect screen material, privacy screen material or generally any suitable sheet of screen material.

Retractable screen assemblies may have a roller located within a roller housing. During withdrawal of the screen into the roller housing, the screen may be generally rolled onto the roller. The screen may be unrolled from the roller when the screen is extended out of the roller housing. The roller may generally be rotationally biased for retraction of the screen into the housing. The housing may be fixed to a side of an architectural opening. The screen may extend between the roller and a moveable draw bar that is manually moveable by a user's hand towards and away from the housing for retraction and extension of the screen. The retractable screen assembly may have guide rails for each end of the draw bar to guide the movement of the draw bar.

The retractable screen assembly may comprise a torsion spring for rotationally biasing the roller for withdrawal or retraction of the screen into the housing and tensioning the screen. The torsion spring may be pretensioned. The screen is drawn from the roller by manually pulling on the draw bar against the tension. Drawing the screen off the roller increases the tension of the torsion spring. When the drawbar is released, the tension in the spring draws the screen back onto the roller and back into the housing. If the torsion spring has too much tension, the draw bar and screen may retract too fast. By contrast, If the torsion spring tension is too low, the draw bar may return too slowly or may even not be able to retract at all.

The Applicant understands that in prior art arrangements, the spring may be pretensioned during manufacture and it may be difficult to adjust the spring tension after manufacture and once a screen has been installed. During manufacture, one end of the screen is attached to the draw bar and the other end to the roller. The screen may be hand-wound onto the roller and then be inserted through an open end of the roller housing. The open15end of the roller housing may then be closed by an end cap, which engages the end of the roller. The required tension for the torsion spring is dependent on a plurality of factors, which may include the size and weight of the screen, and the amount of friction between the guide rails and the draw bar. Consequently, the torsion spring is appropriately tensioned during manufacture to suit a specific retractable screen assembly design.

Kits of parts for retractable screen assemblies may also be made available. A kit may be configured for unskilled installers, for example, homeowners and other “Do it yourself” (“DIY”) installers. During installation, the size of the assembled retractable screen assembly may be changed by changing the length of upper and lower guide rails, for example, by trimming the rails or by using a telescoping action rail. Changing the size of a DIY retractable screen may generally necessitate some adjustment of the tension in the torsion spring. Whether adjustment of the torsion spring assembly is required may not be established or determined until the assembled screen assembly is installed. Consequently, any adjustment of the torsion spring tension would30require subsequent deinstallation or disassembly of the screen so that the end cap of the roller housing may be removed. This is time consuming and inconvenient. Yet further, retractable screen assemblies may be provided with varying arrangements to retain the draw bar when the screen is extended in view of the torsion spring bias, examples of which include a lock body at the drawbar and locking arms extending through the draw bar for actuating guide rail engaging brakes. Such locking arrangements may not be suitable for all retractable screen assemblies Additionally, the kit may be assembled around an architectural opening. For example, the upper guide bar may be first fixed to a wall before another kit part is mounted. Alternatively, the parts of the kit may be assembled prior, and the assembled screen assembly subsequently mounted at the architectural opening.

SUMMARY OF INVENTION

In an aspect, the invention provides a screen retraction mechanism for a retractable screen assembly, the screen retraction mechanism comprising:a roller housing;a roller spinably mounted within the roller housing and for rolling a screen material sheet thereon;a torsion spring coupled to the roller for rotationally biasing the roller; anda tension adjuster coupled to an end of the torsion spring and configured to move in and out of engagement with the roller housing, wherein the tension adjuster is spinnable to selectably tension the torsion spring when out of engagement with the roller housing.

In an embodiment, the screen retraction mechanism comprises a torsion spring assembly comprising the torsion spring, and an end piece disposed at an end of the torsion spring, the end piece being in rotary engagement with the roller.

In an embodiment, the end piece is slidingly received within an end of the roller.

In an embodiment, the torsion assembly comprises another end piece disposed at another end of the torsion spring and coupled to the tension adjuster.

In an embodiment the screen retraction mechanism comprises a rotary damper assembly in rotary engagement with the roller. Preferably, an end of the rotary damper is slidingly received within the roller.

In an embodiment, the tension adjuster and the housing are cooperatively configured for dis engageable threaded engagement. Preferably, the housing comprises an end cap, wherein the end cap and the tension adjuster are cooperatively configured for dis-engagable threaded engagement.

In an embodiment, the tension adjuster comprises a thread having less than a pitch of thread.

In another embodiment, the tension adjuster comprises a plurality of intertwined threads.

In an embodiment, each of the plurality of intertwined threads has less than a pitch of thread.

In an embodiment, the torsion spring can be selectively tensioned to bias the tension adjuster inwards and into threaded engagement with roller housing.

In an embodiment, the roller housing comprises a longitudinal slot shaped screen material port.

In an embodiment, the tension adjuster is externally operable.

In another aspect, the invention provides a kit of parts that can be assembled into a screen retraction mechanism, the kit comprising: a roller housing; a roller for spinably mounting within the roller housing and for rolling screen material sheet thereon; a torsion spring for coupling to the roller for rotationally biasing the roller; and a tension adjuster for coupled to an end of the torsion spring and configured to move in and out of engagement with the roller housing, wherein the tension adjuster is for spinning to selectably tension in the torsion spring when out of engagement with the roller housing.

In another aspect, the invention provides a method of assembling a screen retraction mechanism, the method comprising the steps of: attaching a sheet of screen material to a roller for rolling the sheet of screen material thereon; spinnably mounting the roller within a roller housing; coupling the roller to a torsion spring; coupling a tension adjuster to the torsion spring; operating the tension adjuster to selectively tension the torsion spring; and engaging the tension adjuster to the roller housing.

In an embodiment, the step of operating the tension adjuster comprises the step of externally operating the tension adjuster.

In an embodiment, the step of spinnably mounting the roller within the roller housing comprises disposing the roller between a plurality of roller housing end caps.

In an embodiment, the step of engaging the tension adjuster to the roller housing comprises engaging the tension adjuster to one of the plurality of end caps.

In an embodiment, the step of operating the selectable tensioner comprises selectively tensioning the torsion spring to bias the tension adjuster inwards and into threaded engagement with roller housing.

In another aspect, the invention provides a latch mechanism for a retractable screen assembly, the latch mechanism comprising: a latch keeper; and a draw bar pivotably mounted for pivoting around a pivot axis and comprising a screen material sheet receiver for attachment of an edge of a screen material sheet, and further comprising a latch comprising a latch head engageable with the latch keeper, wherein the sheet screen receiver is displaced in a first orthogonal direction relative to the pivot axis and the latch head is displaced in a second orthogonal direction relative to the pivot axis, whereby tension in the screen material sheet when so received causes the latch head to pivot around the pivot axis into engagement with the latch keeper.

In an embodiment, the draw bar comprises an end cap comprising a rotary bearing at an outwardly orientated face thereof for pivotably mounting the draw bar. Preferably, the end cap comprises the latch head at an outwardly orientated face thereof.

In an embodiment, the end cap defines grooves for receiving a draw bar extrusion.

In an embodiment, the latch mechanism comprises a guide bar orthogonal to the draw bar and which defines a guiding channel in which the rotary bearing and latch head are slidingly received.

In an embodiment, the latch mechanism comprises another guide bar orthogonal to the drawbar, the guide bar and the other guide bar being at opposite ends of the drawbar, and another end cap associated with the other guide bar and comprising another rotary bearing and another latch head sliding received within another guiding channel defined by the other guide bar.

In an embodiment, the latch head is transversely smaller than the rotary bearing.

In an embodiment, the screen material sheet receiver comprises a slot for attaching the screen material sheet.

In an embodiment, the slot is configured to capture a bead.

In an embodiment, the latch keeper comprises a ramp having an inwardly directed apex for latching the latch head.

In an embodiment, the drawbar comprises a finger receiving part.

In yet another aspect, the invention provides a screen assembly for mounting to an architectural opening, the screen assembly comprising:a peripheral frame comprising an architectural opening facing side, the peripheral frame comprising a plurality of mounting clip receivers at the architectural opening facing side and configured to removably engage a plurality of mounting clips for mounting the screen assembly at the architectural opening; anda material screen sheet operationally coupled to the peripheral frame.

In an embodiment, the peripheral frame comprises a plurality of peripheral frame members defining a plurality of mounting clip receiving slots configured to slidingly receive the plurality of mounting clips.

In an embodiment, each of the plurality of mounting clip receiving slots extends along at least a major portion of an associated side of the plurality of sides.

In an embodiment, each of the plurality of mounting clip receivers comprise a plurality of lips that extend partially across a channel opening.

In an embodiment, the plurality of lips defines at least in part a recessed seat for receiving a body of one of the plurality of mounting clips.

In an embodiment, the plurality of mounting clips are penetrable by mechanical fasteners.

In an embodiment, each of the plurality of mounting clips comprise a plurality of resilient clipping projections on opposite sides of a body thereof for receipt by the plurality of mounting clip receivers.

In an embodiment, each of the plurality of mounting clips defines a reinforcing rib.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG.1shows an embodiment of retractable screen assembly generally indicated by the numeral10installed adjacent an architectural opening12in the form of a doorway. The retractable screen assembly10comprises a sheet of screening material32(“screen”), which inFIG.1is partially extended to partially close the doorway12. In this embodiment, the screen32can be further extended such that a distal edge15thereof is adjacent a distal end17of the screen assembly10to close the doorway12. The screening material32is in the form of fiberglass insect screen (“fly screen”). However, other embodiments comprise aluminium insect screen, privacy screen material, vinyl screens or generally any suitable and desired sheet of screening material. In other examples of use, the retractable screen assembly12may be installed adjacent an architectural opening in the form of a window, port, vent doorway or generally any 30 suitable form of architectural opening.

FIG.2shows a partial exploded view of the retractable screen assembly10, with the sheet of screen material32hidden and dimensions rescaled for illustrative purposes. The retractable screen assembly10comprises a roller housing14that is elongated and defines a cavity304. Disposed in the cavity304is a roller200in the form of a tube onto which the sheet of screening material32—which is generally flexible—can be rolled for retraction of the sheet of screen material32into the roller housing14. The sheet of screen material32can be unrolled from the roller200for extending the screen32across the architectural opening12. The roller200is operationally coupled to a torsion spring assembly202, one end of which is disposed in the roller200and engages an internal wall surface thereof. The roller can be rotationally biased by the torsion spring assembly202for retraction of the screen32into the roller housing14. The torsion spring is fixed to the roller housing at the other end as will be described in more detail below.

The retractable screen assembly10comprises a draw bar16parallel to the roller housing assembly and attached to the sheet of screen material32(which inFIG.2is hidden for illustrative purposes). The draw bar16is manually actuatable by a user's hand, for example, for extending and withdrawing the sheet of screen material32across the opening.

As seen inFIG.2, the screen assembly10comprises a top guide rail18and another bottom guide rail20that is parallel to the guide rail18and perpendicular to the draw bar16and roller housing assembly. In this embodiment, the guide rail18is at the top of the architectural opening (“upper guide rail”) and the other guide rail20is at the bottom of the opening (“bottom guide rail”) and parallel to the guide rail18. However, the guide rails18,20may be alternatively vertically orientated for vertical movement of the screen32or have generally any other suitable orientation. The draw bar16is slidingly engaged with the guide rails18,20. The guide rails18,20are provided for guiding movement of the drawbar16, and generally restrict translation of the draw bar16to a linear translation.

The retractable screen assembly10comprises a receiver bar22configured to latchingly engage the draw bar16and so retain the sheet of screen material32in the extended state and close the architectural opening. The receiver bar22is attached to the guide rails18,20by joiners44,46in the form of end caps.30

The retractable screen assembly10in the illustrated embodiments can be assembled in the vicinity of the architectural opening (“that is on site”). The guide rails18,20, roller housing14and receiver bar22are each cut to a suitable length for the architectural opening on site.

FIG.3shows parts of an assembled kit comprising the roller housing14, the roller200, which is disposed in the roller housing14, the draw bar16, and the sheet of screen material32, which is rolled around the roller200and also attached to the draw bar16. The drawbar16comprises an elongate aluminium extrusion310with an upper end cap36and a lower end cap38. The kit can comprise the upper and lower guide rails18,20, receiver bar22(SeeFIG.2), end caps and joiners44,46which are supplied as separate component parts.

As can be seen inFIGS.2and3, the roller housing14comprises a plurality of angles300,302, and upper and lower end caps26,28. The angles300,302comprise extruded aluminium alloy. However, it may also comprise polymer or any other suitable material. When joined by the end caps26,28, the roller housing14defines a longitudinal slot shaped screen port30through which the screen32passes. Upper and lower edges33of the screen32each comprise a bead312to thicken the edge. The beads312are each in the form of a line of zipper teeth, (which can be formed from a length of zipper tape34) attached along the respective edge of the sheet of screen material32. Alternatively, the bead312may comprise a polymer strip or generally be any other suitable bead. As understood with reference toFIGS.3and4, the teeth along the length of the zipper tape34are retained by elongated bead retaining members40in the upper and lower guide rails18,20. The bead retaining members40define a longitudinal slot through which the sheet of screen material passes but which is too narrow to allow the bead312to be pulled therethrough. This arrangement keeps the sheet of screen material32taut, preventing screen “blow out”, while still allowing sliding movement of the beads312within the bead retaining members40.

The bead retaining members40are made from a polymer material, which may reduce sliding friction between the beads312and the bead retaining members40. The bead retaining member40can be slid out of the guide rail20and fed onto the zipper34at the lower edge of the screen. Alternatively, or additionally, the zipper34can be fed into the bead retaining member40. The guide rail20is then pushed onto a mating tab42on the lower end cap28of the roller housing14to attach the guide rail20to the mating tab42by a friction fit. Mechanical fasteners, adhesive or generally any suitable form of attachment may be alternatively used.

FIG.6shows upper and lower joiners in the form of end caps44,46being fitted to the upper and lower ends21,23of the receiver bar22. The receiver bar22is an elongate extrusion with an uneven profile visible inFIG.6. Each end cap44,46has a first projecting tab48configured to be received within a complementary recess50,52at each end of the receiver bar22. Each end cap44,46has a second projecting tab54that is received within a complementary recess56, at the end of the upper and lower guide rails18,20as shown inFIG.7. The projecting tabs54are attached to the guide rails18,20and receiver bar22by a friction fit. Mechanical fasteners, adhesive or generally any suitable form of attachment may be alternatively or additionally used. The tab54has the same configuration as the mating tabs42on the upper and lower end caps26,28of the housing14.

FIG.8shows an isometric view of the front of the assembled screen assembly with the draw bar16pulled across to close the assembly passageway defined by14,18,20and22. The draw bar16is latchingly engaged with the receiver bar22. This configuration provides stability to the screen assembly10for further handling and mounting to a doorway. As shown inFIG.28and explained in foregoing sections, the drawbar16can also be optionally latchingly engaged at an intermediate position along guide rails18and20to allow the screen32to be in a partially open/closed position where the drawbar16engages an intermediate member500. The working of the intermediate member500will be described in detail in the foregoing sections.

FIG.9shows an isometric view of the rear of the screen assembly10which is generally orientated towards the architectural opening12and mounted to a structure in the form of an architrave or trim surrounding the architectural opening12when the screen assembly is installed. The rear walls of each of the housing14, upper and lower guide rails18,20and receiver bar22define an elongate channel58configured to engagingly20receive at least one mounting clip60therein, the engagement being in the form of a snap fit engagement.FIG.10shows a detail of the upper right-hand corner of the screen assembly ofFIG.9, with a mounting clip60received by each of the receiver bar22and guide rail18. For mounting the screen assembly10, adhesive74in the form of a length of double-sided tape is attached to the rear of each of the plurality of mounting25clips60. The rear face of the double-sided tape comprises a removable protector liner76in the form of a strip, that can be removed to reveal the adhesive.

FIG.11shows a section of the receiver bar22with the clip60engagingly received thereby. The clip channel58in the receiver bar22can be a U-shaped channel. The clip channel58has opposing side walls82, a base84and lips86that extend partially30across the open end88of the channel58. As seen inFIG.11, the clip60comprises at least one clip tab66in the form of a leg. During insertion into the channel58, the outer legs66of the clip60deform to deflect inwardly as they are pushed past the lips86, and then relax outwardly when fully inserted so that free ends87are captured behind lips86to form a snap fit connection. The lips86and upper part of the side walls82define a ledge part90with a recessed seat83that receives the body62of the clip60. The recessed seat83and body62are cooperatively configured to, when engaged, resist lateral movement of the installed clip60.

FIG.12shows an isometric view of the rear of a mounting clip60. The mounting clip60has a rectangular planar body62. A plurality of clip elements64in the form of a linear array of three inverted U-shaped resilient projections64extend longitudinally along 10 opposite longitudinal sides the body62. Each projection64has opposed outer and inner leg parts66,68. The U-shaped projections are connected to the base by the inner leg68only such that a gap67is defined between the outer leg66and the base62. The mounting clip60comprises a central longitudinal reinforcing rib70. The mounting clip60also has a fastener receiving aperture72at each end for receiving a mechanical fastener in the form of a screw or generally any suitable form of fastener, for example, a rivet. After the clips60have been installed in the respective channels58,59the protective strip74is removed so as to expose the adhesive74. The screen assembly10can then be placed in the door frame13as shown inFIG.1and held in place by the adhesive74of the clips60on the door assembly. Mechanical fasteners in the form of screws, bolts, or generally any form of suitable fastener can then be used—instead of or additional to the adhesive70to attach the screen assembly10to the structure adjacent the architectural opening12.

FIGS.13and14are cut away views showing mounting screws penetrating a guide rail18,20which can be screwed into the door frame or other 25 suitable adjacent structure. The latching of the draw bar16to the receiver bar22will now be described.

FIGS.15and16respectively show isometric views of the inwardly orientated face and outwardly oriented face of the end caps36,38of the draw bar16. Each of the end caps36,38has the same configuration. The inwardly orientated face of each end cap36,38defines grooves95that are complementary to the profile of the draw bar16extrusion for receiving an end of the draw bar16extrusion and locating the end of the draw bar16extrusion with respect to the end cap36,38.

Each end cap36has a leading end101directed to the receiver bar22and a trailing end103directed to the roller housing14. The trailing end103has a longitudinal slot98that terminates in a rounded slot end99to form a keyhole shaped slot. In use, the rounded end99part retains the bead312of the screen32. Alternatively, or additionally, the edge of the screen32can be fastened within the slot98with adhesive. The end caps36,38further define fastener receiving apertures97for fastening the end caps36,38to the draw bar16. As seen inFIG.16, a latch member100in the form of a latch arm that is elongated and tapered is located on the outwardly orientated face of the end cap36. In use, the latch member100is slidingly received within the channel102—shown inFIG.15of the lower guide rail20. The latch member100has a body104with a leading end106in the direction of travel towards the receiver bar22and a trailing end108. The leading end106terminates in a latch head110in the form of a hook part110. The body104of the latch member100has opposed lateral walls105,111. The wall105is parallel to the longitudinal axis of the end cap36and terminates in the shank107of the hook part110. The front wall111is inclined relative to the wall105.

FIG.17shows an isometric view of the rear of the screen assembly10, without the screen32for illustrative purposes, wherein the draw bar16is in a closed position and latchingly engaged to the receiver bar22.FIGS.18to20show cut away views of the draw bar16, lower guide rail20and guide rail end cap44, during latching of the draw bar16to the receiver bar22. The right-side drawings are cut through a lower plane than the left side drawings. The draw bar16defines a rear slot130for receiving another bead (not shown) at the distal edge of the screen32. The draw bar16has a finger receiving part132in the form of a handle adjacent the leading edge136for a user to actuate the draw bar16. In use the, latch member100extends into and travels along channel102of the lower guide rail20as may be seen inFIGS.18to20. The trailing end108has a protruding bearing part134in the form of a slidingly received protruding rotary bearing134that has a transverse dimension substantially the same as the width of the channel102. Thus, the rotary bearing134of the latch member100is captured within the channel102and also functions as a guide for the draw bar16.

The channel102is defined by lateral side walls136,138including a rear side wall136and a front side wall138. As the rear wall105of the latch member100is parallel to the longitudinal axis of the latch member100, the rear wall105is generally aligned with the wall138of channel102. The inclined wall103is inclined away from the wall138of the channel102.

The draw bar can pivot around the bearing part134as shown inFIGS.18and19. The bead of the screen32inserted into the slot130is laterally displaced relative to the bearing part134, and consequently exerts a torque on the draw bar16around the bearing part134to rotate the latch member100into engagement with then receiver part120in the form of a latch keeper of the end cap44that couples the receiver bar22to the lower guide rail20. The latch member100enters the latch keeper120through entrance aperture127. The receiver part120is configured to communicate with channel102of the guide rail20.

The latch keeper120comprises a ramp having an inwardly directed apex131to define a rear hook receiving cavity137. The end cap44has a rear side wall122side (with respect to the rear of the guide rail) and a front side wall131and an end wall125connecting the rear side wall122and the front side wall131. As shown inFIG.19, when the hooked leading edge110of the latch member100meets the ramp120, the hook110rides over the ramp so as to cause the draw bar16to pivot against the bias as shown inFIG.19. When the hooked part110passes the latch keeper120, the bias of the screen returns the latch member100into an engaged position on the latch keeper120so as to latch the draw bar16to the receiver bar22.

A user can disengage the draw bar16by actuating the handle132of the draw bar16to rotate the draw bar and disengage it from the receiver bar11. The tension in the biased screen23can then withdraw the screen32into the roller housing14. The mechanism for adjusting the tension of the screen23is now described in more detail. As seen inFIG.2, a roller200inside the roller housing14has a generally round outer surface around which the screen32is rolled when retracted. Disposed within the roller200is a torsion spring assembly202for rotationally biasing the roller200. A rotary damper assembly204in the form of a viscodynamic brake (for example, a viscodynamic brake manufactured by AQUS, Italy) is also enclosed within roller200so as to slow or brake retraction of the roller200. Other damper or brake mechanisms may be used, for example a linear friction bearing.

The torsion spring assembly202and rotary damper assembly204are secured to the upper and lower end caps26,28of the roller housing14by means of upper and lower adjustment and connecting members206,208and screws210as will be described further below.FIG.21is a cut away view of the roller200, spring assembly202and rotary assembly204installed within the roller14.FIG.22shows an exploded view of the torsion spring assembly202andFIG.23shows a partial cut away view showing the torsion spring assembly202installed in the roller housing14. Disposed within the torsion spring assembly202is rod214. An end piece in the form of a lower end cap228and another end piece207in the form of a head part are disposed at opposite ends of the torsion spring and capture the rod214within the torsion spring212. The lower end cap228has a circular base217and an upstanding inwardly tapered sleeve218that receives the lower end of the rod214. The upper cap206comprises a separable head part207and a tapered sleeve209for receiving an upper end of the rod214.

As shown inFIG.23, the head207has a hexagonal projection222with a central bore223. The roller200slidingly receives the end cap228such that it is rotationally engaged. The circular base217of the lower end cap228has vertical ribs229. The roller200has complementary internal ribs (not shown) that that engage ribs on the cap228such that rotation of the roller200will cause the lower cap228to rotate. Alternatively, or additionally, keys or splines may be used to rotationally engage the roller200and the circular base.217. The roller200can be cut to size and still generally receive the end cap228.

FIG.24shows top and bottom isometric views of the upper end cap26of the roller housing, the upper cap216and a tension adjuster206. The tension adjuster206can be rotated to tension the spring. The external face of the cap26has an arrow268(as seen inFIG.24) that indicates the direction of rotation for increasing torsion in the torsion spring212and the tension in the screen. The upper end cap26and in turn the upper part of the spring212are prevented from rotating as the upper end cap26is held in place by connection to the adjustment member206that is, in turn, in threaded engagement with the upper part of spring assembly202.

Tension adjuster206comprises a plurality of intertwined or overlapping threads. Each of the plurality of threads optionally comprise less than a pitch of thread. That is, each of the plurality of intertwined threads do not make a full turn or revolution around an axis of the tension adjuster206. The tension adjuster may comprise only one thread in some other embodiments. A proximal edge of the screen32is fixed to the roller200by an adhesive in the form of adhesive tape. However, it may be fixed using a clamping strip, fasteners in the form of screws, or generally any suitable way of fixing. As the roller200rotates one way the screen32is extended from the roller housing14, one end of the torsion spring212associated with the end cap26is caused to rotate with the roller200whereas the other end of the spring212associated with the lower end cap28is held stationary. The torsion spring212can be pretensioned. To pretension the torsion spring212, the upper part of the torsion spring212is rotated without movement of the lower part of the spring212. As shown inFIG.23the spring assembly202is operationally coupled (in this embodiment indirectly connected) to the upper roller housing end cap26by means of the connection between the upper end cap26and the tension adjuster206. The tension adjuster206is in the form of a cap with a circular head224attached to a lower cylindrical body or shank226. As shown inFIG.23, the cylindrical body226has a hexagonal aperture227for receiving and engaging the hexagonal projection222, thereby providing a socket type connection. The tension adjuster206is externally operable so that it can be accessed from outside of the roller housing14without opening the housing14. The head224also has a hexagonal recess225for receiving the head of a complementary tool in the form of a hex key that can be actuated to rotate the tension25adjustment member206. The tension adjuster206defines an aperture229for receiving a fastener in the form of a screw210that threadingly engages projection222so as to secure the parts together and prevent rotational movement of the upper cap26relative to the upper end of torsion spring assembly202. In the present embodiment, but not necessarily in all embodiments, it is not necessary to roll the screen onto the roller prior to insertion of the roller into the roller housing. The roller200may be inserted into the housing14with the draw bar16spaced away from the housing14by the screen32. The end cap26may then be fitted to the upper end of the roller housing14and the tension adjuster206inserted through the bore230of the end cap26until the hexagonal projection222is received within bore227of the tension adjuster206.

The tension adjuster206can subsequently be rotated so as to roll the screen onto the roller200within the roller housing14. As the upper and lower ends of the torsion spring212are free to move, no tension is generated during this process. When the screen32has been fully rolled onto the roller200, and the draw bar16is adjacent to the roller housing14, the roller housing14interferes with the draw bar16, preventing further rotation of the roller. At this point, tension may be applied to the torsion spring212by continuing turning the tension adjuster206. When the desired degree of tension has been obtained, the tension adjuster is secured against further rotation or movement by threadingly engaging the tension adjuster206and the upper cap26. The adjuster206is then secured in place by a screw210that is received within a complementary bore223in the hexagonal projection222. The spring212is in a longitudinally compressed state. The screw210locks the tension adjuster206adjacent the upper end cap26, which prevents a longitudinal bias of the spring pushing the tension adjuster206all the way out of the end cap16during the tensioning procedure. The longitudinal bias of the spring212allows the torsion spring assembly202to at least partially extend out of the end cap26during tensioning. As the tension is increased, the spring212shortens to withdraw the tension adjuster206into the endcap26. The torsion in the torsion spring212causes the tension adjuster206to automatically screw into the end cap26, securing of the tension adjuster26.

FIG.25is a partially cut away view of the lower roller housing14in which the rotary damper assembly204is disposed. The rotary damper assembly204has a body filled with a viscous fluid for damping the force applied by the torsion spring. The rotary damper assembly204includes an upper end cap242that fits over the spring250. A ring244with external ribs246is at the top of the end cap242. The ribs244are configured to cooperate with recesses in the internal surface of the roller200for rotation therewith. The lower part of the rotary damper assembly204includes an end cap260with a base264and an upstanding spindle262.30The respective upper and lower parts of the rotary damper assembly204are spaced apart and are flexibly coupled by a spring250in the form of a coil spring. The spring250has three sections, an upper section252, an intermediate section254and a lower section256. The upper section252has a constant first diameter configured to fit over the lower section256of the damper, the lower section256has a constant second diameter less than the first diameter to fit over the spindle262and the intermediate section254has a reducing diameter from the first diameter to the second diameter. The spring250may be cut to size to assemble roller housings14of different length. This 5 enables a roller housing14to be easily cut to size on site. A washer270separates a base264from the spring250.FIG.27shows a detail of the lower end cap28, lower attachment member or connector208, and end cap260. Parts can be interchanged to assemble either right-handed or left-handed screens as both the spring assembly202and the rotary damper assembly10204may be joined to the same upper end cap26or lower end cap. The end cap260is in turn mounted onto the connector28by means of an annular hexagonal projection266in the base264(shown inFIG.27) being received within the complementary hexagonal recess237in the connector28. It will be appreciated that the connector28and lower end cap28are identical to the15upper end cap26and tension adjuster206as described above.

Referring toFIG.28, an optional drawbar engaging member500is provided to allow the screen to be left in an intermediate open/closed position. Like reference numerals describe features that have been previously described in earlier sections. The engagement member500comprises a spring-loaded member520that is biased by a spring525and retained within a cylindrical body510. During installation, the drawbar engaging member500may be positioned at any location along the top rail18or bottom rail20. In the preferred embodiment, the intermediate member500is located within the channel102of the bottom rail20to engage with end cap38that forms part of the draw bar assembly16. The spring loaded member520comprises a convergent configuration (conical) which allows the end cap38to contact and travel past the spring loaded member520during an initial opening operation. During such an opening operation, a structure positioned at one of the underside of the end cap38pushes the spring loaded member520in a downwardly direction as the end cap38travels past the engaging member500when the latch assembly is engaged. When the latch is no longer engaged, the end cap38catches the spring loaded member520and prevents the screen from returning to the fully open position.

Now that embodiments have been described, it will be appreciated that some embodiments may have some of the following advantages:Embodiments may be adjusted to suit different sized screens, and this allows the frame to be cut to a required size at an installation site.Friction due to some degree of installation misalignment can be compensated for on site.The retraction tension can be adjusted without disassembling the screen.The tension can be adjusted using standard tools, including standard drivers, and thus no special tools are needed. A power tool is generally not needed.Each turn of the driver turns one end of the spring once, and so spring tension is quickly increased (unlike earlier designs that were tensioned with a drill requiring multiple revolutions). Consequently, the number of turns can be easily counted so iterative adjustments are easier to make.The intertwined threads provide multiple engaging parts to increase strength.30The step rake on the threads may enable quick disengagement for tensioning, and a “self seating” feature.The hook of the latch may be biased onto the latch keeper without the need for extra springs. It is relatively easy to manually pivot the latch to disengage from the latch keeper.Clips may make it easy to mount the retractable screen and release the retractable screen from the clips. It may be easier to take the retractable screen down if necessary and then put it up again. There is freedom to choose where to attach the mounting clips.Pre-tensioning the torsion spring may not require that the entire end cap to be rotated. In order to adjust the tension of an installed screen, it may not be necessary to remove the end cap.The latch member may double as the guide member thereby simplifying10construction (and reducing cost). There may be no moving parts associated with the draw bar extrusion. This may allow the draw bar to be cut to size.There may be no additional latch engagement members or the like on the receiver bar extrusion, thereby providing no limitation as to how the drawbar extrusion may be cut to size.The bias of the latch member to the closed position is improved by the tension of the screen, further minimizing the number of moving parts.The mounting clips allow for easier installation. Further, as the mounting clips are separably mountable to the screen frame members, the mounting clips may be mounted in the desired locations depending upon the relative dimensions of the respective frame members.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. The term “comprises” and its variations, such as “comprising” and “comprised of” is used throughout in an inclusive sense and not to the exclusion of any additional 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.