GB2534995A

GB2534995A - Guided screen system

Info

Publication number: GB2534995A
Application number: GB1522207.8A
Authority: GB
Inventors: Dibben Martin
Original assignee: Ideas by Design Ltd
Current assignee: Ideas by Design Ltd
Priority date: 2014-12-23
Filing date: 2015-12-16
Publication date: 2016-08-10
Also published as: GB201522207D0; WO2016102933A1

Abstract

The system (10) has: a pair of guide rails (12), each having a channel (16) extending in a first direction; and a roller blind (14) between the guide rails. The roller blind includes a blind fabric (20) having lateral side profiles (30) configured to slide in the first direction along the channels as the blind fabric is deployed, with each lateral side profile including at least one shoulder region (32) to abut an opposing surface of the respective channel in order to avoid the blind fabric being pulled out of the channels. The shoulder region of at least one lateral side profile comprises at least one strand (34) stitched to the blind fabric.

Description

TITLE: GUIDED SCREEN SYSTEM

TECHNICAL FIELD

The present invention relates to a guided screen system of the kind comprising a retractable screen which is deployed between a pair of spaced apart guide rails.

BACKGROUND ART

A typical guided screen system comprises a roller blind and a pair of guide rails which, in use, are disposed on either side of an aperture to he screened. The roller Mind comprises a roller with a blind fabric wound therearound. The lateral side edges of the blind fabric are provided with an edge profile with an enlarged head region which is configured to slide in an axial direction along a specially shaped groove or keyway in each of the rails, whilst resisting pull out in a direction transverse to the axial direction, as the blind fabric is wound on or off the roller. The edge profile is typically provided by one half of a zipper (hereinafter referred to as a "half zipper") attached to a lateral side of the blind fabric, with the teeth of the half zipper forming the enlarged head region. However, the edge profile could be formed by a soft or semi-rigid polymer moulding such as a hot-melt synthetic resin or rubber.

US 4638844 and GB 2235005 disclose early forms of such a screen system, with different brackets for loosely mounting the guide rail, and W02009/098433 discloses a current form of such a screen system.

There are certain disadvantages to using a half zipper to form the required edge profile of a guided screen system. Conventional zip-like guided screens typically have relatively coarse half zippers for engaging the rail keyways (i.e. half zippers with teeth at least 1.5rnm thick). Such relatively coarse half zippers may be securely retained in appropriately sized rail keyways, sufficient at least for most internal installations. However, such relatively coarse half zippers are often considerably thicker than the blind fabric, and this can lead to a number of problems.

For example, when wound onto the roller, the half zippers take up more room in a radial direction than the blind fabric, thereby necessitating the use of bigger housings than would be required to fit the blind fabric alone. Also, when winding the blind fabric onto its roller, there is a tendency for the half zippers to spiral with an axial spread, rather than remain in a single plane, which conflicts with the aim of retaining the blind fabric between thc rails. When the blind fabric and half zipper spirals to one side, the blind fabric is tilted to that one side which may cause the weight bar on the bottom of the blind fabric (hem bar) to tilt meaning it is no longer level. If the spiral abuts an adjacent surface, the blind fabric may then start to spiral in the opposite direction, so tilting the blind fabric and hem bar in a counter direction. This cycle repeats until the blind is fully raised.

The blinds of such conventional zip-like guided screens also suffer from wrinkling at the edge, where the half zipper (or more specifically a strip of fabric to which the zipper teeth are attached during manufacture of the half zipper) is welded/attached to the blind fabric. This wrinkling is caused by the difference in blind build-up on the roller between the single thickness of the blind fabric (between the half zippers) and the greater thickness of the half zippers at the edges. The differences in thickness cause stretching of the blind fabric at the edges which is seen as wrinkling when the blind is deployed. In a similar way, there is a difference in blind build-up diameter between the blind fabric in the middle and the half zippers at the edge, causing stress in the blind fabric when wound on the roller between the tight roll at the edges (because of the thickness of the half zippers) and the loose roll in the middle (between the between the half zippers). Such stress may cause creasing in the blind fabric on the roller, particularly when relatively thin blind fabrics are used and with larger blinds.

In an attempt to overcome some of the problems of relatively coarse half zippers, the use of relatively fine half zippers (i.e. half zippers with teeth less than 1.5mm thick) has been contemplated. However, even when such relatively fine half zippers arc used with rails with correspondingly sized keyways, there is a tendency for the blind fabric to pull all too easily its relatively fine half zippers away from the rails. This tendency remains even when the keyway is lined with specially shaped inserts. Hence, the relatively fine half zippers are considered to provide insufficient anchorage in their respective rail keyways.

The present applicant has sought to provide an alternative way of achieving the edge profile required in a guided screen system in order to reduce or overcome some of the disadvantages associated with the use of half zippers.

DISCLOSURE OF INVENTION

According to one aspect of the present invention, there is provided a guided screen system, comprising: a pair of guide rails, each guide rail having a channel extending therealong in a first direction; and a roller blind comprising a roller with a blind fabric wound therearound, the blind fabric having lateral side profiles configured to slide in the first direction along the channels as the blind fabric is deployed from the roller, with each lateral side profile including at least one shoulder region which is configured to abut an opposing surface of the respective channel in order to resist a force tending to pull the blind fabric out of the channels in a direction perpendicular to the first direction, characterised in that the at least one shoulder region of at least one lateral side profile comprises at least one strand stitched to the blind fabric.

Stitching a strand directly to the blind fabric avoids the need for the strip of fabric to which zipper teeth are conventionally pre-stitched prior to the strip of fabric being attached to the edge of the blind fabric e.g. by welding. When the blind is configured as a "blackout blind", and the blind fabric is made from blackout material, part of the strip of fabric which extends beyond the blackout material may be problematic because it typically is not opaque and thus has the potential to allow light to seep around the lateral side edges of the Hind fabric. Stitching at least one strand to the blind fabric in accordance with the present invention avoids this problem.

The size of the shoulder region may depend upon a number of factors, including the thickness of the blind fabric and the width of the channel where the shoulder region engages the opposing surface to prevent the blind fabric pulling out of the channel. The shoulder region may protrude at least 0.1mm, and perhaps at least 0.2mm or even at least 0.25mm, from a surface of the blind fabric. On the other hand, the shoulder region may protrude less than 2.0mm and perhaps less than 1.5mm or even less than 1.0mm, from a surface of the blind fabric. Although increasing the size of the protrusion may help to increase the resistance of the Hind fabric to pulling out of the channel, too large a protrusion may lead to problems when winding the blind fabric onto the roller similar to those encountered with conventional half-zippers as noted above.

At least one lateral side of the blind fabric may be reinforced with an edging strip or tape. The edging strip/tape may be applied to one surface of the blind fabric only. Alternatively, the edging strip/tape may be applied to both surfaces of the blind fabric, and may even extend around a lateral side edge of the blind fabric. The strip/edging tape may be welded to the blind fabric, and the blind fabric may be a blackout blind fabric (e.g. a foam-backed opaque fabric). The at least one strand may he stitched to the blind fabric through the edging strip/tape.

Each lateral side profile may include two shoulder portions, one on each surface of the blind fabric, with the two shoulder portions of each lateral side profile being configured to butt against a pair of opposing surfaces of the respective channel in order to resist a force tending to pull the Hind fabric out of the channels in a direction perpendicular to the first direction. The pair of opposing surfaces of the respective channel may be defined by flanges on opposing side walls of each channel, the flanges projecting inwardly to form a constriction in the cross-section of the channel.

The at least one strand may be a monofilament (e.g. a nylon monofilament) or a thread made up of multiple filaments. The at least one strand stitched to the blind fabric may take many different forms, depending on strand size as well as the stitch size, frequency and spacing, provided the shoulder region is sufficiently well defined to engage the opposing surface of the channel. For example, the at least one strand may itself be stitched into the blind fabric (e.g. the at least one strand may be formed as a running stitch extending along at least part of one side of the blind fabric). With such a configuration, the shoulder region may consist of the at least one strand stitched into the blind fabric. The present applicant has appreciated that the at least one strand may take the place of the teeth of the half zipper traditionally used in a guided screen system, thereby obviating the need for the half zipper altogether. Although the teeth of a half zipper are typically pre-stitched to a strip of fabric for attachment to the blind fabric, it is the teeth and not the stitching that provide the shoulder region which is configured to engage the opposing surface of the channel to prevent the blind fabric pulling out of the channel.

Alternatively, the at least one strand may be stitched to the blind fabric by another strand (e.g. the at least one strand may be looped, laid onto one surface of the blind fabric and stitched thereto by said another strand). In one arrangement, two looped strands may be laid on to respective surfaces of the blind fabric and stitched thereto by said another strand. The two looped strands may even extend beyond a perimeter of the blind fabric, where the two looped strands may be entwined. With such arrangements, the looped strand or strands may define the shoulder region that is configured to engage the opposing surface of the channel to resist the blind fabric being pulled out of the channel.

The at least one strand may define loops with U-shaped portions that alternately extend over opposite surfaces of the blind fabric. Each U-shaped portion may have two legs, each leg being secured to a surface of the blind fabric by said another strand. The base of each U-shaped portion may define a protuberant surface configured to abut an opposing surface of the respective channel.

In accordance with another aspect of the present invention, there is provided a method of manufacturing a roller blind for a guided screen system, comprising: providing a blind fabric to be wound around a roller; and stitching at least one strand to a lateral side of the blind fabric to form a lateral side profile including at least one shoulder region which is configured in use to slide in an axial direction along a channel in a guide rail of the guided screen system whilst resisting pull out in a direction transverse to the axial direction. The al least one strand may be stitched to the lateral side of the blind fabric in achieve any of the arrangements described with reference to the first aspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a schematic view of a guided screen system, in accordance with one embodiment of the present invention; and Figure 2 is an exploded cross-sectional view of parts of the guided screen system of Figure 1, taken along line II-II.

Figures 3A and 3B are plan and detail views of a lateral edge region of the blind fabric of a guided screen system according to a second embodiment of the present invention.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENT

Figure 1 shows a guided screen system 10, embodying the present invention, and comprising a pair of guide rails 12 and a roller blind 14. Each guide rail 12 has a channel 16 extending therealong in an axial direction indicated by arrow A. The roller blind 14 comprises a roller (not shown) and a blind fabric 20 wound around the roller. The blind fabric 20 has lateral side profiles 30 which are configured to slide in the axial direction along the channels 16 as the blind fabric 20 is deployed from the roller. Each lateral side profile 30 includes at least one shoulder portion 32 which is configured to engage the respective channel 16 as described below in order to resist being pulled out of the channel 16 in a direction perpendicular to the axial direction.

As shown in Figure 2, a first shoulder portion 32 is formed at least in part by a first strand 34 stitched to the blind fabric 20. By 'stitched to' is meant a direct engagement of the strand with the (possibly reinforced) lateral extremity of the blind fabric, without any intermediate strip of fabric of the kind discussed above. In this particular embodiment, the first strand 34 is looped and laid onto a front surface 36 of the blind fabric 20, and is stitched thereto by a running stitch 38. A second shoulder portion is formed in an analogous manner on a rear surface 40 of the blind fabric 20 by a second strand 42, looped and laid onto the rear surface 42 and stitched thereto by the running stitch 38. Portions of the looped first and second strands 34, 42 extending beyond a perimeter 44 of the blind fabric 20 are entwined. The channel 16 in the guide rail 12 is formed by a pair of spaced apart walls 50. Each wall 50 has a flange 52 projecting inwardly to define a restricted opening 54 at the top of the 5 channel 16. Each flange 52 has a surface 56 extending from the restricted opening 54 and facing a bottom surface 58 of the channel 16 The restricted opening 54 is wider than the thickness of the blind fabric 20 alone, but not wider than the combined thickness of the blind fabric 20 and the first and second strands 34, 42. Furthermore, the channel 16 has a depth which is greater than the width of the lateral side profile 30. This means that the blind fabric 10 20 is able to slide along the channel 16 with the shoulder portion 32 contained between the surfaces 56 and the bottom surface 58. Furthermore, if the blind fabric 20 experiences a force threatening to pull the blind fabric 20 out of the channel 16 in a direction perpendicular to the axial direction, the shoulder portions 32 will press against the surfaces 56 to prevent the lateral side profile 30 from being pulled out of the channel 16.

Figures 3A and 3B are plan and detail views of an edge region of the blind fabric of a guided screen system according to a second embodiment of the present invention, those features common with the first embodiment being indicated by common reference numbers.

As shown in Figure 3A, blackout blind fabric 20 (e.g. a foam-backed opaque fabric) has lateral side profiles 30 configured to slide along channels as the blind fabric is deployed from the roller. Referring to figure 3B, each lateral side profile 30 includes at least one shoulder region 32 having a protuberant surface 32' configured to abut an opposing surface of a respective guide channel.

In the embodiment shown, shoulder region 32 is defined by a monofilament strand 34 (e.g. a nylon monofilament) that crosses hack and forth across the perimeter 44 of the blind fabric, thereby defining U-shaped loops 60 that alternately extend over the front and back surfaces 36,40 of the lateral edge of the blind fabric, the mouths of the U-shaped loops lying proximate the lateral edge.

The U-shaped loops define two shoulder regions 32, one on each side of the hlind fabric, the base of each U-shaped loop 60 defining a protuberant surface 32' for abutment with a guide 30 channel.

Strand 34 is stitched to the blind fabric 20 by another strand 38 that passes throueh the blind fabric. Specifically, each of the two legs 60A,60B of each U-shaped loop 60 is secured to the corresponding surface of the blind by means of a running stitch 38 that passes back and forth through the fabric of the blind.

The lateral edge of the blind fabric may be reinforced with an edging strip or tape as indicated at 70 prior to the strand 34 being stitched to the blind fabric by the stitch 38 (which will consequently pass through the edging tape as well as through the blind fabric). In (he embodiment shown, the edging strip/tape is applied to both surfaces of the blind fabric by welding and extends around the lateral perimeter 44 of the blind fabric.

In another embodiment., not shown, the at least one strand defusing at. least one shoulder region may itself he stitched into the blind fabric, i.e. the strand passes through the blind fabric. Specifically, the strand may be formed as a running stitch extending along at least part of one side of the blind fabric. Such a running stitch may itself secure other elements to the blind fabric as per the embodiment of figure 3, discussed above.

Claims

CLAIMS1. A guided screen system, comprising: a pair of guide rails, each guide rail having a channel extending therealong in a first 5 direction; and a roller blind disposed between the guide rails and comprising a roller with a blind fabric wound therearound, the blind fabric having lateral side profiles configured to slide in the first direction along the channels as the blind fabric is deployed from the roller, with each lateral side profile including at least one shoulder region which is configured to abut an opposing surface of the respective channel in order to resist a force tending to pull the blind fabric out of the channels in a direction perpendicular to the first direction, characterised in that the shoulder region of at least one lateral side profile comprises at least one strand stitched to the blind fabric.
2. A guided screen system according to claim 1, in which the shoulder region protrudes at 15 least 0.1mm from a surface of the blind fabric.
3. A guided screen system according to claim 1 or claim 2, in which the shoulder region protrudes less than 2.0mm from a surface of the blind fabric.
4. A guided screen system according to any one of the preceding claims, in which at least one lateral side of the blind fabric is reinforced with an edging tape.
5. A guided screen system according to any one of the preceding claims, in which each lateral side profile includes two shoulder portions, one on each surface of the blind fabric, with the two shoulder portions of each lateral side profile being configured to abut a pair of opposing surfaces of the respective channel in order to resist a force tending to pull the blind fabric out of the channels in a direction perpendicular to the first direction.
6. A guided screen system according to claim 5, in which the pair of opposing surfaces of the respective channel is defined by a pair of flanges on opposing side walls of each channel, the pair of flanges projecting inwardly to form a constriction in the cross-section of the channel.
7. A guided screen system according to any one of the preceding claims, in which the at least one strand is itself stitched into the blind fabric.
8. A guided screen system according to claim 7, in which the at least one strand is formed as a running stitch extending along at least part of one side of the blind fabric
9. A guided screen system according to any one of claims 1-6, in which the at least one strand is stitched to the blind fabric by another strand.
10. A guided screen system according to claim 9, in which the at least one strand is looped, laid onto one surface of the blind fabric and stitched thereto by said another strand.
11. A guided screen system according to claim 10, in which first and second strands are looped, laid on to respective surfaces of the blind fabric and stitched thereto by said another 5 strand.
12. A guided screen system according to claim 11, in which the first and second looped strands extend beyond a perimeter of the blind fabric where they are entwined.
13. A guided screen system according to claim 10, in which the at least one strand defines loops with U-shaped portions that alternately extend over opposite surfaces of the blind fabric.
14. A guided screen system according to claim 13, wherein each U-shaped portion has two legs, each leg being secured to a surface of the blind fabric by said another strand.
15. A guided screen system according to claim 13 or claim 14, wherein the base of each U-shaped portion defines a protuberant surface configured to abut an opposing surface of the respective channel.
16. A guided screen system according to any one of the preceding claims, in which the blind fabric is blackout material.
17. A method of manufacturing a roller blind for a guided screen system, comprising: providing a blind fabric to be wound around a roller; stitching at least one strand to a lateral side of the blind fabric to form a lateral side profile including at least one shoulder region which is configured in use to slide in an axial direction along a channel in a guide rail of the guided screen system whilst resisting pull out in a direction transverse to the axial direction.