GB2599131A

GB2599131A - A profile

Info

Publication number: GB2599131A
Application number: GB2015161.9A
Authority: GB
Inventors: Maher Christopher
Original assignee: Dash Components Ltd
Current assignee: Dash Components Ltd
Priority date: 2020-09-25
Filing date: 2020-09-25
Publication date: 2022-03-30
Anticipated expiration: 2040-09-25
Also published as: GB202015161D0; GB2599131B

Abstract

The present application describes an elongate rail member with a uniform cross section 200 for a roller blind: with a first side 202, spaced apart from a second side 204; with an upper opening 209 between the two; with a first wall 214 extending between the two sides, and a second wall 220 extending from the upper region of the second side, so that it reaches beyond a vertical central axis 222 of the rail member, to overlap an upper region of the first side. The second wall may be at an angle of between 0 to -75 degrees with respect to a horizontal axis and may define a cavity 224 which the blind fabric slides into. There may be a third wall which may be parallel with a horizontal axis and the first and second sides may be curved. A roller blind comprising the rail and a method of assembling the roller blind are also disclosed.

Description

A PROFILE

The present invention relates to a profile for a roller blind and in particular, but not exclusively, to the cross-sectional profile of a bottom rail member for a roller blind.

A conventional roller blind typically includes an elongate member, known as a bottom rail, located along the lower edge of the sheet fabric of the blind. The lower edge of the fabric is typically folded over on itself to provide a relatively thick lower edge region which is then slid along the bottom rail to be secured therein. End caps are typically located on/in each end of the bottom rail to prevent the fabric sliding out of the bottom rail. The bottom rail is for aesthetic purposes and to add weight to the lower edge region of the fabric to keep it taut. The bottom rail is sometimes engaged in a runner located on each side of the blind which guide the bottom rail up and down as the blind is opened and closed.

However, conventional bottom rail profiles are not suitable for relatively thick and/or heavy and stiff fabrics as folding these thicker fabrics over on themselves is difficult and in turn feeding the lower edge region into and along a conventional bottom rail is particularly difficult, if not impossible.

It is an aim of certain embodiments of the present invention to provide a bottom rail for a roller blind which allows any thickness and/or weight of blind fabric to be efficiently and securely located in the bottom rail.

It is an aim of certain embodiments of the present invention to provide a bottom rail for a roller blind which speeds up assembly times and in turn saves time and energy.

According to a first aspect of the present invention there is provided an elongate rail member for a roller blind, comprising: a substantially uniform cross-sectional profile comprising a first side portion laterally spaced apart from an opposed second side portion to define an upper opening along the rail member; a first wall portion extending across the profile from the first side portion to the second side portion; and a second wall portion extending from an upper edge region of the second side portion towards the first side portion, wherein the second wall portion extends beyond a vertical central axis of the profile to overlap an upper edge region of the first side portion which extends substantially up to the vertical central axis.

Optionally, the second wall portion is oriented an angle of between 0 and -75 degrees with respect to a horizontal axis of the profile.

Optionally, the second wall portion is oriented an angle of around -55 degrees with respect to the horizontal axis.

Optionally, the second wall portion extends beyond the vertical central axis of the profile by around 2-10mm.

Optionally, the second wall portion is vertically spaced from the first wall portion to define a cavity therebetween for slidably receiving a lower edge region of a fabric blind.

Optionally, a first region of the second wall portion is oriented an angle of between 0 and -75 degrees with respect to a horizontal axis of the profile.

Optionally, the first region of the second wall portion comprises an angled region oriented at around -55 degrees with respect to the horizontal axis.

Optionally, the second wall portion comprises a second region oriented parallel to the horizontal axis of the profile.

Optionally, the second region extends from the second side portion and the first region extends from the first side portion.

Optionally, the second region extends from a central region of the second side portion and the first region extends from a lower region of the first side portion.

Optionally, the rail member comprises a third wall portion extending across a lower region of the profile from the first side portion to the second side portion.

Optionally, the third wall portion is substantially parallel with a horizontal axis of the profile.

Optionally, the first and second side portions are substantially curved.

Optionally, the first and second side portions are substantially convex to each provide a convex outer surface having substantially the same radius of curvature.

According to a second aspect of the present invention there is provided a roller blind comprising a rail member according to the first aspect of the present invention.

According to a third aspect of the present invention there is provided a method of assembling a roller blind, comprising: slidably inserting a lower edge region of a blind fabric along a cavity of an elongate rail member having a substantially uniform cross-sectional profile comprising a first side portion laterally spaced apart from an opposed second side portion to define an upper opening along the rail member, wherein the cavity is defined by a first wall portion extending across the profile from the first side portion to the second side portion and a second wall portion extending from an upper edge region of the second side portion towards the first side portion, wherein the second wall portion extends beyond a vertical central axis of the profile to overlap an upper edge region of the first side portion which extends substantially up to the vertical central axis; urging a first region of the fabric in a first lateral direction with respect to the vertical central axis of the profile by an edge region of the second wall portion; and urging a second region of the fabric located above the first region of the fabric in a second lateral direction opposed to the first lateral direction by the upper edge region of the first side portion.

Optionally, the method comprises creating a first fold line across the fabric in which the edge region of the second wall portion locates.

Optionally, the method comprises creating a second fold line across the fabric in which the upper edge region of the first side portion locates.

Optionally, the method comprises mounting an end cap to each end of the rail member.

lo Description of the Drawings

Certain embodiments of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 illustrates an isometric view of a bottom rail according to certain embodiments of the present invention; Figure 2a illustrates a cross-sectional view of the bottom rail of Figure 1; and Figure 2b illustrates the cross-sectional view of the bottom rail of Figures 1 and 2a with the lower edge region of a blind fabric located therein.

Detailed Description

As illustrated in the Figures, an elongate bottom rail 100 for a roller blind has a cross-sectional profile 200 which is substantially uniform along its length which includes a substantially curved and convex first side portion 202 laterally spaced apart from a substantially curved and convex second side portion 204 opposed to the first side portion 202. The first and second side portions 202,204 have substantially the same radius of curvature, albeit defining outer surfaces 206,208 of different lengths. Alternatively, the side portions may be substantially concave or substantially flat, vertically oriented and parallel with each other. The side portions define an upper opening 209 along the rail 100.

The first and second side portions 202,204 are joined together proximal to their lower ends by a base wall portion 210 extends therebetween. The base wall portion 210 is disposed above the lower ends of the first and second side portions to thereby define a dove-tail channel region 212 along the lower edge of the bottom rail 200. The lower ends are configured such that the vertical central axis of the profile is oriented substantially vertically with respect to a horizontal support surface, e.g. a window sill, if the bottom rail is lowered in use to sit thereon.

An intermediate wall portion 214 extends between the first and second side portions 202,204 and across the profile to add further strength and stiffness to the rail 100.

The intermediate wall portion 214 extends substantially horizontally from the upper region of the second side portion 204, and substantially parallel with the base wall portion 210, before extending diagonally downwardly at an angle of around 0 to 75 degrees, and preferably around -55 degrees (i.e. downwardly), with respect to the horizontal region 216 to join the lower region of the first side portion 202. The angled region 218 is aptly around three to four times the length of the horizontal region 216. Alternatively, the intermediate wall portion 214 may include a single region which extends substantially horizontally across the profile between the two side portions.

An upper wall portion 220 extends diagonally downwardly from the upper end of the second side portion 204 at an angle of around 0 to 75 degrees, and preferably around -55 degrees (i.e. downwardly), with respect to a horizontal axis of the profile. Aptly, the upper wall portion 220 is substantially parallel with the angled region 218 of the intermediate wall portion 214. The upper wall portion 220 terminates within the interior space of the profile and beyond a vertical central axis 222 of the profile, as illustrated in Figure 2a. The upper edge of the first side portion 202 terminates on the vertical central axis 222 of the profile such that an overlap exists between the upper wall portion 220 and the upper edge of the first side portion 202. Aptly, the length of overlap is around 1-10mm, and aptly around 2-3 mm, in the lateral direction, and the free end of the upper wall portion 220 is vertically spaced apart from the intermediate wall portion 214 by around 5-10 mm. A cavity 224 is thereby created between the upper wall portion 220 and the intermediate wall portion 214 for locating a lower edge region of a blind fabric to secure the same to the bottom rail, as illustrated in Figure 2b. Alternatively, the upper wall portion may extend substantially horizontally across the vertical central axis towards the first side portion.

As also illustrated in Figure 2b, the overlap provided by the upper edge of the first side portion 202 and the upper wall portion 220 urges the fabric 300 to fold in an opposed direction (referenced B) compared to the fold (referenced A) proximal to its lower edge 302 which is located in the cavity 224. This opposed folding of the fabric at two spaced apart regions A,B above its lower edge acts to nip the fabric and apply a shear loading across the fabric to thereby secure the same with respect to the bottom rail in both the longitudinal and lateral directions. The spaced apart relationship of the upper wall portion 220 and the intermediate wall portion 214 defines the relatively spacious cavity 224 which is thereby configured to receive a relatively thick/heavy fabric material which conventional bottom rails are not suitable for.

To assemble a roller blind, the lower edge region of a fabric blind 300 is inserted into a first open end of the bottom rail 100 such that its lower edge 302 is located in the cavity 224 defined between the upper wall portion 220 and the intermediate wall portion 214. The angled region 218 of the intermediate wall portion 214 urges the lower edge region of the fabric upwardly and into the cavity, particularly when the fabric is relatively thick and/or heavy weight. The lower fabric portion 304 'below' the first fold line A is located in the cavity 224 and aptly engages with the underside of the upper wall portion 220. Aptly, the upper surface of the lower fabric portion 304 includes a layer of a plastics material, such as a stretched polyester film, e.g. MylarTm, or the like, attached to the fabric which protects the fabric and reduces the coefficient of friction between the free edge of the upper wall portion and the inner surfaces of the cavity to thereby allow the lower fabric portion 304 to slide easily and quickly into the cavity 224 during assembly. The arcuate region of the cavity defined by the horizontal region 216 of the intermediate wall portion 214 and the upper wall portion 220 allows for a wide range of fabric thicknesses and flexure to allow the free edge of the fabric to be located at a number of rotational positions in the cavity about the first fold line A. The free end of the upper wall portion 210 engages the intermediate fabric portion 306, or aptly a plastics material layer attached thereto, above the first fold line A and urges the intermediate fabric portion 306 beyond the central axis 222 of the profile 200 to be on an opposed side of the axis relative to the lower edge of the fabric. The intermediate fabric portion 306 extends upwardly at an angle to the upper edge of the first side portion 202 which engages the fabric and creates the second fold B. Engagement of the upper edge of the first side portion 202 with the fabric provides a flush finish between the fabric and the bottom rail. The remaining fabric 308 extends substantially vertically upwardly from the upper edge of the first side portion 202 and is kept taut by the weight of the bottom rail. The bottom rail hangs substantially vertically from the second fold line B in view of the profile being configured such that a centre of gravity thereof when the fabric is inserted therein lies substantially on the vertical central axis 222 such that the bottom rail does not lean forwards or backwards relative to the vertical oriented blind fabric 308. End caps (not shown) are mounted on or in the respective ends of the bottom rail to aesthetically finish off the rail and laterally secure the blind fabric therein.

Aptly, the bottom rail 100 is extruded from aluminium, but may be any suitable material, such as steel or a plastic for heavy or light-weight applications respectively. Aptly, the radius of curvature of the first and second side portions 202,204 is around 23mm, the maximum width of the rail is around 16mm, the height of the rail is around 32mm, the opening defined by the upper edge of the first side portion and the upper edge of the opposed second side portion is around 5mm, the horizontal region of the intermediate wall portion is vertically spaced from the lower edge of the profile by around 17mm, and the wall thickness of the profile is uniform and around 1mm. Aptly, the bottom rail may be any suitable length to suit the desired width of blind.

Certain embodiments of the present invention therefore provide a bottom rail for a roller blind which allows any thickness and/or weight of blind fabric to be efficiently and securely located in the bottom rail. The bottom rail according to certain embodiments of the present invention also increases the speed of assembling a blind and in turn saves time and energy.

Claims

Claims 1. An elongate rail member for a roller blind, comprising: a substantially uniform cross-sectional profile comprising a first side portion laterally spaced apart from an opposed second side portion to define an upper opening along the rail member; a first wall portion extending across the profile from the first side portion to the second side portion; and a second wall portion extending from an upper edge region of the second side portion towards the first side portion, wherein the second wall portion extends beyond a vertical central axis of the profile to overlap an upper edge region of the first side portion which extends substantially up to the vertical central axis. 2. 3. 4. 5. 6.
The rail member according to claim 1, wherein the second wall portion is oriented an angle of between 0 and -75 degrees with respect to a horizontal axis of the profile.
The rail member according to claim 2, wherein the second wall portion is oriented an angle of around -55 degrees with respect to the horizontal axis.
The rail member according to any preceding claim, wherein the second wall portion extends beyond the vertical central axis of the profile by around 2-10mm.
The rail member according to any preceding claim, wherein the second wall portion is vertically spaced from the first wall portion to define a cavity therebetween for slidably receiving a lower edge region of a fabric blind.
The rail member according to any preceding claim, wherein a first region of the second wall portion is oriented an angle of between 0 and -75 degrees with respect to a horizontal axis of the profile.
7. The rail member according to claim 6, wherein the first region of the second wall portion comprises an angled region oriented at around -55 degrees with respect to the horizontal axis.
8. The rail member according to claim 7, wherein the second wall portion comprises a second region oriented parallel to the horizontal axis of the profile.
9. The rail member according to claim 8, wherein the second region extends from the second side portion and the first region extends from the first side portion.
10. The rail member according to claim 9, wherein the second region extends from a central region of the second side portion and the first region extends from a lower region of the first side portion.
11. The rail member according to any preceding claim, comprising a third wall portion extending across a lower region of the profile from the first side portion to the second side portion.
12. The rail member according to claim 11, wherein the third wall portion is substantially parallel with a horizontal axis of the profile.
13. The rail member according to any preceding claim, wherein the first and second side portions are substantially curved.
14. The rail member according to claim 13, wherein the first and second side portions are substantially convex to each provide a convex outer surface having substantially the same radius of curvature.
15. A roller blind comprising a rail member according to any preceding claim. 30
16. A method of assembling a roller blind, comprising: slidably inserting a lower edge region of a blind fabric along a cavity of an elongate rail member having a substantially uniform cross-sectional profile comprising a first side portion laterally spaced apart from an opposed second side portion to define an upper opening along the rail member, wherein the cavity is defined by a first wall portion extending across the profile from the first side portion to the second side portion and a second wall portion extending from an upper edge region of the second side portion towards the first side portion, wherein the second wall portion extends beyond a vertical central axis of the profile to overlap an upper edge region of the first side portion which extends substantially up to the vertical central axis; urging a first region of the fabric in a first lateral direction with respect to the vertical central axis of the profile by an edge region of the second wall portion; and urging a second region of the fabric located above the first region of the fabric in a second lateral direction opposed to the first lateral direction by the upper edge region of the first side portion.
17. The method according to claim 16, comprising creating a first fold line across the fabric in which the edge region of the second wall portion locates. 15
18. The method according to claim 17, comprising creating a second fold line across the fabric in which the upper edge region of the first side portion locates.
19. The method according to any of claims 16 to 18, comprising mounting an end cap to each end of the rail member.