GB2192022A - Secondary glazing - Google Patents

Abstract

A secondary double glazing system comprising a spring-rolled roller blind 11 of flexible translucent plastics film 21 with hinged rigid plates, running down side regions to clamp the bind when unrolled. The bottom edge 28 clip fits in channel 26. The blind passes between rubber and bristle lips (18, 19 respectively Fig. 2 not shown) of a canopy which remove condensation and dust, respectively. <IMAGE>

Description

SPECIFICATION Secondary double glazing system Field of the Invention The invention relates to secondary double glazing systems.

Review of Art Known to the Applicant Secondary double glazing systems are wellknown as a general kind of glazing system, and there are several equally wellknown types of secondary double glazing systems currently available commercially.

The best known is essentially a rigid-panel system in which panes of glass are built into a surrounding framework which is itself built onto the room-facing framework of an existing window. Conventionally the framework which surrounds the panes is an aluminium framework, and the panes swing or (more usually) slide into and out of position to allow a user to seal off the outside window or to gain access to it from inside the room according to need.

Such rigid-panel framed secondary double glazing systems tend to be expensive. In another known form of rigid-panel system, therefore, panes of relatively rigid transparent plastics material are screwed to the roomfacing framework of the existing window, either directly or via an extruded plastics peripheral strip which clamps the plastics panes against the existing window frame. This is considerably cheaper than the glass-and-aluminium system outlined above, but it is also slightly less effective and it does not look as pleasing when installed. It is, like the firstmentioned system, still relatively expensive and it requires a degree of skill to install properly.

In an attempt to cut down the expense of such systems, secondary double glazing systems have been developed which use clear flexible plastics film instead of rigid glass or plastics panes. One such system is marketed under the trade designation "SELLOTAPE Seasonal Double Glazing" in the United Kingdom by the Sellotape products division of D R G (UK) Limited. It consists simply of a sheet of clear flexible transparent plastics film which is initially clamped across the area of the roomfacing frame of an existing window, and is held in position in a relatively taut and wrinklefree state by an extruded UPVC strip which is screwed around the periphery of the window frame to bear against the edge regions of the sheet; and then the sheet is heat-shrunk by playing a conventional hair dryer across its surface to tighten it within the confines of the peripheral holding strip.

The system just outlined is indeed relatively cheap to buy and to install, but it again needs a degree of skill in order to give a neat and wrinkle-free result. Because it covers the full window area in a single sheet, the original windows cannot be opened or closed from inside the room, once the secondary double glazing sheet is installed. This can be a considerable drawback.

There is another flexible-film-based system which, whilst not as cheap as the SELLOTAPE system just reviewed, does avoid its main drawback. This system is currently marketed in the United Kingdom by Rollerglaze Limited of Wrexham, under the trade mark INSUB LIND. As the name implies, the system consists essentially of a spring-rolled roller blind, mounted (as other roller blinds are conventionally mounted) so that the roller axis extends across the top of the room-facing window and with the ends of the roller stopping just short of the extremities of the frame sides. The blind comprises a sheet of thin flexible transparent plastics film approximately 125 micron in thickness.Touch-and-close fastening strip of the kind sold under the trade mark VELCRO in the United Kingdom extends around the window frame surfaces and around the opposite longitudinal edges and the bottom edge of the blind. With the blind unrolled and pulled fully down, its side edges and its bottom edge can be pressed against the window frame surfaces to adhere to them, and a simple cam mechanism is then operated to push the blind roller hard against the top of the window frame to seal all four edges of the blind releasably against the window frame.

The system just outlined is still relatively expensive, and with time the VELCRO filaments become contaminated and the sealing efficiency reduces. However, the use of flexible plastics film instead of rigid glass or plastics panes, and the use of known and widely-available spring-rolled blind mechanisms, do have advantages for the user looking for an effective yet inexpensive system of secondary double glazing.

Summary of the Invention According to the invention, a secondary double glazing system comprises a springrolled roller blind of flexible translucent plastics film with means for mounting the blind to run across the top region of an existing roomfacing window, characterised by the provision of respective rigid plates, each of which plates is adapted to be mounted so as to run down one respective side region of the existing window and incorporates provision for the plate, when so mounted, to be moved back from the adjacent window side surface-without having to be removed completely therefrom-to allow the blind to be unrolled, and with provision for each said plate to be clamped against the adjacent window side surface, when the blind has been unrolled and pulled fully down, to trap the adjacent edge of the blind between that plate and the said surface.

Thus, the system acknowledges and incorporates the need for a positive sealing of the opposite side edges of the unrolled blind against the existing window, whilst providing an altogether more positive and long-lasting seal along each of those side edges than does the known VELCRO-styie sealing strip used on the known INSUBLIND system.

A system embodying the present invention is based on the intention that the opposite side edges of the secondary double glazing sheet are properly sealed.

because side-draughts from windows cause much more discomfort and much more heat loss than do down draughts or up draughts.

Unlike the known system, a system embodying the present invention sets out to seal those side edges properly.

In another advantageous development of the invention, the system components are so sized and constructed that the blind, when in position and fully unrolled, overlaps not the edges of the existing room-facing window frame but instead overlaps the edges of the wall-opening in which that frame is installed.

This makes the system as a whole much easier to install in an existing room, the sealing is easier to achieve if the blind edge regions are pressed against the room walls, rather than against the window frame members, and the blind will move in front of any objects which might be standing on the windowsill rather than having to be fitted in behind them. It is wellknown that plants, ornaments and the like invariably end up occupying most, if not all, of the available windowsill surfaces in domestic buildings. One drawback of roller blinds as opposed to the traditional curtains is a wellknown tendency for such objects to hinder the final stages of unrolling of a roller blind. A system embodying this advantageous subsidiary aspect of the invention will avoid that tendency.

Preferably there is provision in the system to seal the bottom edge of the unrolled blind, as well as the side edges, against the adjacent window surface. Where the window has a sill, such provision may comprise a channel adapted to be fixed to the sill so as to extend fully across the sill, and adapted to receive the necessarily-reinforced bottom edge of the blind.

Advantageously, in the case just outlined, the channel receives the reinforced bottom edge of the blind in a resilient clip-grip, to make quite sure that the seal is an efficient seal in the context of draught exclusion.

Preferably also the top edge of the blind is sealed against draughts when the blind is unrolled, by mounting the roller in a housing from which the blind emerges past opposed lips, at least one of which lips is resiliently flexible and bears against the other, and with the housing so configured that when it is mounted in position, the opening defined by the lips lies substantially adjacent the window surround surface.

The configuration just defined is more easily achieved if the system is intended to be mounted on the wall rather than against the existing window frame. This is another advantage of adapting the system deliberately to be mounted on the wall rather than, as is conventional, against the room-facing window frame.

Means to clean the blind may be incorporated into the roller mounting or roller housing, such means advantageously comprising a lip spanning the blind and against which the blind bears as it unrolls. The lip just referred to may, in the case where opposed lips are used in a roller housing, comprise one or both of such opposed lips.

The opposite side plates may be finished on their respective room-facing surfaces with a decorative finish, for example a wood-grain finish simulating such woods as sapele, teak and mahogany. This looks far better than the VELCRO strip previously referred to. Especially where the blind overlaps the edges of the window opening, two opposite side strips of wood-finish, each running down the wall adjacent an edge of the window opening, can look extremely attractive. If the householder does not want them to be visible, or does not consider that they do look particularly attractive, they can, in any event, be hidden by the existing conventional drawn-back curtains, and the blind itself would equally well be hidden by a conventional window pelmet.It is thus possible for all the advantages of secondary double glazing to be enjoyed, without the high cost of rigid-panel systems, and with virtually the entire system being hidden from normal view if the user so desires.

Brief Description of the Drawings The accompanying drawings show, by way of example only, one way of putting the invention into practice. It is currently the best way known to tWapplicant, although it is not the only way. In these drawings: Figure 1 shows in perspective a system embodying the invention, with the blind almost fully unrolled; Figure 2 shows details of the system in end elevation; Figure 3 shows details of the side plates of the system when viewed from above; Figures 4 and 5 show, in perspective and in end elevation respectively, modifications to the system of Figures 1 to 3.

Description of the Preferred Embodiment The spring-loaded roller 11 of a roller blind extends between respective opposite-end mountings 12, 13 each of which is fixed to opposite ends of a back plate 14 to form an integrally assembled unit housing the roller and the blind. Lugs 15, 16 project upwards from each of the mountings 12, 13 and are slotted, as shown in Figure 1, so that the roller housing can be screwed to and suspended from the wooden batten 17 which spans the top of a window opening and which is, itself, screwed to the room-facing surface of the wall in which the opening is formed. The batten 17 conventionally carries a curtain rail which, for clarity, is not shown.

As Figure 2 shows particularly, the lugs 15, 16, and the backs of the mountings 12, 13, are so shaped that when the housing 12, 13, 14 is screwed into place on the batten 17, the backplate 14 lies flat against the wall. Lips 18, 19 are each resiliently flexible and extend the whole of the length of the blind housing so as to span the window opening and overlap its opposite side edges. One of the lips 18 is a resiliently flexible rubber strip. The other lip 19 bears against it and is a similarly resiliently flexible bristle pile strip. The blind itself emerges from between these lips 18, 19 and is referenced 21.

The blind 21 is a sheet of flexible transparent clear plastics film approximately 125 micron in thickness and currently sold in the United Kingdom under the trade mark MELINEX by Imperial Chemical Industries PLC. It is rectangular, and it is sized so that it' s opposite longitudinal edges 22, 23 overlap the opposite side edges of the window opening by an appreciable amount. The rubber strip 18 wipes any condensation, and the bristle pile strip 19 cleans away any dust, which may have formed on either of the blind surfaces in use, as the blind is rolled back into its housing.

Respective rigid plates are fixed to run down the wall in which the window opening is formed, so as to overlap each opposite longitudinal edge 22, 23 of the blind 21.

Each of these side plates comprises a back plate 24 hinged along its outer edge to a front plate 25. The back plate 24 is substantially flat. The front plate 25 is creased along its length to accommodate the thickness of the back plate 25 and the much thinner blind 21 so that, as Figure 3 shows in full line, the inner longitudinal edge of the front plate 25 lies flat against the wall when the plate 25 is swung fully home.

As Figure 3 also shows, each plate 25 can be hinged so as to open right back from the adjacent edge 22, 23 of the blind 21. In the particular embodiment illustrated, one of the plates 24, 25 is magnetic and the other is magnetically attracted to it, so that when the plate 25 is fully opened then it is too far away to be magnetically attracted to the other plate of the hinged pair; but when it is fully shut, as shown in full line in Figure 3, it is held firmly against its associated other plate and traps the blind edge 22 or 23 against the wall as shown.

The back plates 24 of each pair 24, 25 are screwed to the wall or otherwise fixed by means which form no inventive part of the system.

A U-section channel 26 is similarly screwed to the windowsill 27 of the window and spans the sill across the beyond the opposite side edges of the window opening. At least one of the two walls of this channel 26 is resiliently flexible towards and away from the other wall. The conventionally reinforced bottom edge 28 of the blind 21 is a clip-fit in the channel 26 when the blind is pulled fully down.

Figures 4 and 5 show a modification for windows which have no sill. The blind is rolled fully down so that its bottom edge 28 comes below the bottom edge of the window opening. Ends 29, 31 of the rod which reinforces the bottom edge 28 of the blind project from the blind and hook under respective clips 32, 33 fixed to the wall. A two-part plate 34, similar in construction and operation to the plates 24, 25, is initially swung open as shown in Figure 5 to allow the blind ends to be hooked under the clips 32, 33 and is then swung up against the wall to be magnetically held in place and to trap the bottom edge of the blind, immediately above the edge-reinforcing rod, firmly against the wall and so seal it against draughts from the window.

Other modifications could be made to the illustrated embodiment within the scope of the invention. For example, the front plate 25 of each plate pair 24, 25 could be spring-loaded towards the wall, or could hold one or more captive bolts which, when unscrewed, allow the plate to be swung away from the wall but which then screw into threaded bores in the back plate 24 to trap the blind edge. Other modifications will become apparent to those skilled in the field to which the invention relates.

Claims (9)

1. A secondary double glazing system comprising a spring-rolled roller blind of flexible translucent plastics film with means for mounting the blind to run across the top region of an existing room-facing window, characterised by the provision of respective rigid plates, each of which plates is adapted to be mounted so as to run down one respective side region of the existing window, and incorporating provision for the plate, when so mounted, to be moved back from the adjacent window side surface-without having to be removed completely therefrom-to allow the blind to be unrolled, and with provision for each said plate to be clamped against the adjacent window side surface, when the blind has been unrolled and pulled fully down, to trap the adjacent edge of the blind between that plate and the said surface.

2. A secondary double glazing system according to Claim 1 in which the system com ponents are so sized and constructed that the blind, when in position and fully unrolled, overlaps the edges of the wall-opening in which that frame is installed.

3. A secondary double glazing system according to Claim 1 or Claim 2 in which there is provision to seal the bottom edges of the unrolled blind, as well as the side edges, against the adjacent window surface.

4. A secondary double glazing system according to Claim 3 and for use on a window with a sill, in which the provision to seal the bottom edge of the blind comprises a channel adapted to be fixed to the sill so as to extend fully across the sill, the channel being adapted to received the necessarily reinforced bottom edge of the blind.

5. A system according to claim 4 in which the channel receives the reinforced bottom edge of the blind in a resilient clip-grip.

6. A system according to any of the preceding claims in which the top edge of the blind is sealed against draughts when the blind is unrolled, by mounting the roller in a housing from which the blind emerges past opposed lips, at least one of which lips is resiliently feixible and bears against the other, and with the housing so configured that when it is mounted in position, the opening defined by the lips lies substantially adjacent the window surround surface.

7. A system according to any preceding claim in which the roller mounting or housing incorporate means to clean the blind, said means comprising a lip spanning the blind and against which the blind bears as it unrolls.

8. A system according to Claim 7 when appendant to Claim 6, in which the lip to clean the blind comprises one or both of the opposed lips past which the blind emerges.

9. A system substantially as described herein with reference to and as illustrated in the accompanying drawings.