The present invention relates to stair rails.

The assembly of a stair rail apparatus typically involves the connection of a horizontal or inclined hand or shoe rail to vertically extending posts, such as baluster posts which interconnect hand and shoe rails. A connector device suitable for providing such a rail - post connection, or a rail - rail connection, must not only be accurately positioned in between the two stair rail components it interconnects, but must also be able to provide maximal structural support and rigidity to the assembled stair rail apparatus.

For example, when connecting a baluster post to a hand rail or shoe rail (or both) of a stair rail assembly care must be taken to ensure that the connector device interconnecting the post and rail is properly position along the given rail so as to be in line with other neighbouring connector devices connecting neighbouring baluster posts of the stair rail assembly. Improper lateral alignment of the connector device results not only in an aesthetically displeasing appearance (the stair rail appearing poorly assembled) but also may significantly reduce the structural rigidity of the completed stair rail and/or the ability of an opposing rail to subsequently connect to the free end of the misaligned intermediate baluster post.

Such interconnected rail and post components of a stair rail assembly are often vulnerable to excessive lateral forces across the plane containing the hand/shoe rail and connected baluster post, and the point of interconnection of rail and post assembly components is particularly vulnerable to breakage or damage when subjected to such forces.

The present invention aims to provide a stair rail assembly which addresses at least some of the aforementioned problems encountered in existing stair rail assemblies.

At its most general, the present invention proposes the combination of a rail component and a connector device to be connected to it in use in which the connector device is shaped to abut and at least partly embrace a reciprocally shaped structural part of the stair rail component in use. The reciprocal shaping of the part of the rail component to which the connector device is to be abutted may greatly reduce the possibility of misplacement of the connector device, and the reciprocal shaping of the connector device to embrace that part of the component helps add structural rigidity and strength to the assembled apparatus.

Accordingly, in a first of its aspects, the present invention may provide a stair rail apparatus including a component defining a channel with a base surface at least part of which is shaped to project or extend into said channel, and a connector device arranged to connect to said component via an abutment portion thereof defining a recess shaped to receive said projecting or extending base surface part such that parts of the abutment portion within the recess abut the received projecting base surface part when the connector device is connected to the component in use.

Consequently, defining a channel in the aforesaid component (e.g. stair hand/shoe rail, post etc.) provides a clearly structurally identifiable abutment area thereon indicating to the user the precise lateral (and possibly longitudinal) position at which the connector device should be abutted to the component in use. Most preferably the width of the channel corresponds with the lateral dimension of the abutment portion such that lateral opposing walls of the channel substantially prevent lateral movement of the abutment portion when the latter is abutted to the base of the former in use. Furthermore, the abutted parts of the received projecting base surface, by action of that abutment, are able to provide a physical obstruction and/or a surface enabling a generation of a reactive force against lateral forces acting upon the component or the connector device urging lateral movement of the one relative to the other. That is to say, the connector device is to some extent able to "hold on to" the received projecting base surface portions of the component by virtue of the fact that the recessed abutment portion to some extent "embraces" those projections base surface parts. A generally flat channel base would not enable this embrace to occur.

The recess is preferably shaped to reciprocate the shape of said projecting or extending base surface part. For example, the base surface of the channel is preferably generally convex, and the recess defined by the abutment portion preferably presents a generally concave region shaped to reciprocate the shape of said generally convex base surface part and is preferably arranged for intimate abutment therewith in use.

The aforementioned base surface, when convex, may be a curved convex surface (e.g. having a constant or varying, radius of curvature) or may comprise a series of adjacent and contiguous flat surface parts defining a projection having a polygonal cross section (e.g. forming a ridge of triangular cross section, or square cross section or the like) .

While the projection base surface parts, when received within the reciprocally shaped abutment portion of the connector device, assists in providing structural strength and guidance during assembly/positioning of the stair rail apparatus components, other parts of the aforementioned channel may also assist in providing these benefits. For example, the abutment portion of the connector device preferably has a lateral dimension matching the lateral width of the channel base such that the connector device fits snugly within the channel in use, being held in position not only by the received convex base portions but also by opposing walls of the channel.

Preferably, the channel defines a pair of opposing channel walls and the abutment portion is shaped to simultaneously abut, in use, opposing parts of the channel where the opposing channel walls meet the channel base. It is to be noted that the opposing channel walls, and/or those parts of the channel where the opposing channels walls meet the channel base, assist not only in positioning/centring within the aforementioned channel but also provide a surface against which a reactive force may be generated in opposition to transverse forces applied to the connector device in use.

The abutment portion may define a plurality of separate abutment surfaces within said recess, each separate abutment surface may be arranged to abut the received projecting base surface part when the connector device is connected to the component in use. For example, where a plurality of separate abutment surfaces are provided within the recess, each abutment surface may be arranged within the recess such that a plurality of abutment surfaces simultaneously abut, in use, opposing parts of the channel where the opposing channel walls meet the channel base. Preferably, where a plurality of separate abutment surfaces are provided within the recess, they are positioned within the recess at maximum lateral separation therein.

Alternatively, the abutment portion may define a single continuous abutment surface within said recess arranged to abut the received projecting base surface part when the connector device is connected to the component in use.

The recess defined by the abutment portion may be presented outwardly of the connector device. That is to say, the abutment portion may be defined by external parts of the connector device which are directly accessible and are not concealed or partially concealed (at least until such time as the connector device is abutted to the channel base surface in use) .

Alternatively, the abutment portion may form a sleeve shaped to receive a part of said component including said channel, the inner sleeve surface defining said recess.

Where the abutment portion forms a sleeve, an outer wall of the sleeve may be provided with an access opening formed adjacent the recess in the abutment portion. The opening preferably extends along the sleeve wall in the direction of the channel the base of which the recess is shaped to receive. The access opening is preferably so arranged to expose at least a part of the channel when received in the sleeve thereby permitting access to the base of the channel by the abutment portion of another connector device of the type having an outwardly presented abutment portion. The access opening enables the two types of connector device to be positioned upon a common stair rail component (e.g. a hand or shoe rail) in much closer proximity to each other than would otherwise be the case.

The access opening may be a slot extending into the sleeve outer wall from the outermost peripheral rim of the wall. The stair rail assembly may provide said component defining the channel, the connector device of the variety defining a sleeve, and another connector device of the type having an outwardly presented abutment portion. The stair rail assembly may provide these three assembly parts in assembled form with each of the two types of connector device connected to the same component via abutment to the channel defined thereby.

Preferably, the connector device has attachment means arranged to attach the connector device to a further component of the stair rail apparatus thereby to interconnect the further component with the component to which the abutment region of the connector device is abutted in use. The stair rail apparatus may include the further component. Thus, the connector device may connect to, and interconnect two stair rail components, such as a hand/shoe rail to a post (e.g. a baluster) or a hand/shoe rail to another hand/shoe rail. The further component may define a second channel with a base surface shaped to project into said second channel, said attachment means being arranged to connect to said further component via an abutment portion of the attachment means defining a recess shaped to receive the projecting base surface part of the second channel such that parts of the abutment portion of the attachment means within the recess abut the received projecting base surface part of the second channel when the attachment means is connected to the further component in use. The attachment means may possess some or all of the aforementioned preferable or alternative features of the abutment portion of the connector device as discussed above.

The aforesaid component of the apparatus may be provided interconnected to the further component via the connector, device. The component may be a shoe rail or a hand rail, and the further component may be a post. The component may be a shoe rail or a hand rail, and the further component may also be a shoe rail or a hand rail.

The component (and/or further component) defining the channel (or second channel) may be a post or rail and the channel defined thereby is preferably elongate and extends along the direction of the longitudinal axis of the component. For example, when the component (and/or further component) is a hand/shoe rail, or a post, the channel (or second channel) preferably extends linearly along the length of the component in the direction of the long axis thereof.

It is contemplated that the stair rail assembly may be made and sold in kit form comprising unassembled components arranged for subsequent assembly by a user. In a second of its aspects, the present invention may provide a kit of parts for providing, when assembled, a stair rail assembly according to the invention in its first aspect and including some, none or all of the preferred/alternative features discussed above.

In a third of its aspects, the present invention may provide a kit of parts for a stair rail assembly including a component defining a channel with a base surface at least part of which is shaped to project into said channel, and a connector device arranged to connect to said component via an abutment portion defining a recess shaped to receive said projecting base surface part such that parts of the abutment portion within the recess abut the received projecting base surface part when the connector device is connected to the component in use.

In a fourth of its aspects, the present invention may provide a stair rail assembly comprising the stair rail apparatus in assembled form, according to the invention in its first aspect and including some, none or all of the preferred/alternative features discussed above.

In the stair rail assembly, the component defining said channel may be a hand rail or a shoe rail, and said further component may be connected to the hand/shoe rail by said connector device abutted to the channel base of the hand/shoe rail within said channel.

The stair rail assembly may include both a hand rail and a shoe rail and a post there between, each rail defining a respective said channel and each rail being connected to an opposite respective end of said post by a respective connector device such that the post interconnects the hand rail and the shoe rail via two said connector devices.

Examples of the invention shall now be described with reference to the accompanying drawings in which: Figure 1 illustrates in cross-section a stair rail apparatus including a connector device interconnecting a hand rail to a baluster post; Figure 2 illustrates a cross-sectional view of the hand rail component of the stair rail apparatus of figure 1; Figure 3 illustrates an exploded view of the connector device of the stair rail apparatus of figure 1 in which the abutment portion is outwardly presented thereof; Figure 4 illustrates an alternative embodiment of the connector device in which the connector device defines a sleeve within which the abutment portion is formed; Figure 5 illustrates a further alternative embodiment of the connector device in which the attachment means thereof defines a sleeve containing an abutment portion. Figure 6 schematically illustrates a cross-sectional view of two types of connector device connected to a mutual stair rail component, one connector device defining an access slot within which the other connector device is received.

Figure 1 schematically illustrates a cross-sectional view of a stair rail assembly including a hand rail 1 defining a channel with a convex base surface 2, a connector device 9 abutted, via an abutment portion 8 thereof, to the hand rail at its channel base, and a baluster post 7 attached to the connector device 9 via an attachment means thereof in the form of a socket 6. Thus, in the stair rail assembly of figure 1, the connector device 9 interconnects the hand rail 1 to the baluster post 7.

The channel defined by the hand rail 1 is circularly convex with a constant radius of curvature such that, when viewed in the cross-sectional plane to which the long axis of the hand rail 1 is perpendicular, the projecting base surface defines a circular ark. The channel also defines a pair of opposing channel walls 3 which define the lateral sides of the channel. Each channel wall 3 meets with the curved channel base to define a substantially right-angled channel corner 4.

The abutment portion of the connector device 8 defines a recess 5 shaped to receive the projecting base surface 2. The recess is concavely shaped to reciprocate the convex shape of the projecting base surface and the radius of concave curvature of the former substantially matches the radius of convex curvature of the latter such that the two intimately abut each other in use as illustrated in figure 1. The recess 5 of the abutment portion 8 intimately abuts the convex channel base across the full lateral width of the channel base extending to and abutting against opposing right-angular channel corners 4. The abutment portion may also abut opposing channel walls 3 at parts of (or all of) the height of those walls adjacent the connector device.

It is to be noted that while the embodiment illustrated in figure 1 shows an abutment portion defining a recess 5 providing a single continuous abutment surface arranged to abut the received projecting channel base surface, in alternative embodiments the abutment portion made provide a plurality of separate abutment surfaces within the recess, each separate surface abutment being arranged to abut the received projecting base surface part of the component to which the connector device is connecting in use. An example of such a plurality of separate abutment surfaces is illustrated in figures 4 and 5 herein.

The connector device 9 includes attachment means 6 comprising a socket extending from a surface of the abutment portion 8 other than the abutment surface. A baluster is received within the socket defined by the attachment means such that the connector device 9 interconnects the baluster post 7 and the hand rail 1. The connector device 9 may be fixed in abutment to the hand rail 1 by any suitable fixing means (e.g. nail, screws, adhesives) .

By virtue of the geometry of the recess 5 defined by the abutment portion and the projecting base surface 2 of the hand rail channel received therein, the former is able to, at least partially, embrace the latter. When a transverse force Fl acts upon the baluster post 7 in typical use, the transverse force is to some extent transferred to the connector device 9 interconnecting the baluster post and the hand rail. This transferred transverse force component will urge the abutment portion 8 of the connector device to slip/slide transversely across the surface of the hand rail to which it is abutted. However, the surface area of the projection channel base 2 abutting the abutment portion, and facing in a direction opposing the transverse force Fl experienced by the baluster post, provides a surface against which a reactive force F3 may be generated as between the abutment portion and the hand rail with which to resist the transverse sliding force Fl. A similar reactive force F2 is provided at the face of the channel wall 3 facing in the direction generally opposite to that of the transverse force Fl. In this way, the recessed abutment portion, together with the received projecting channel base surface enables greater structural strength in the stair rail assembly components shown in figure 1.

Figure 2 illustrates separately the cross-sectional view of the hand rail component 1 illustrated in figure 1. The hand rail is generally cylindrical in shape having a cylinder radius R. The channel 2 defined by the hand rail extends linearly along the direction of the cylindrical axis of the hand rail (perpendicular to the page of Figure 2) along the outer surface thereof. The channel base surface is convex with a constant radius of curvature r (where r is less than R) and is coplanar with the radius R of the hand rail at all points along the hand rail. The radius of curvature r of the channel base surface is centred at a point within the hand rail lying upon a diameter of the hand rail but displaced by an amount D from the centre of curvature of the outermost surface of the hand rail such that R = D + r. This relationship ensures that, at its maximum height of projection, the channel base surface 2 projects to a radial distance equal to, but not exceeding, the radius R of the hand rail as measured from the centre of curvature of the hand rail. The width of the channel 2 subtends and angle of 90° to the centre of curvature of the channel. Appropriate choices of the displacement D and the angles subtended by the width of the channel at its centre of curvature determine the height of opposing channel walls 3.

Figure 3 illustrates an exploded view of one example of a connector device 9. It is to be understood that the connector device may take other forms such as those illustrated in figures 4 to 6 herein. In figure 3 the connector device includes a first body portion 60 defining an abutment portion 8 having an outwardly presented abutment surface 5. The connector device also includes a second body portion 61 arranged to be pivotally attached to the first body portion and having an attachment socket 6 within which an end of the baluster post 7 is received.

A pivot assembly is provided at the interface between the first and second body portions by which the second body portion is able to be pivotally attached to the first body portion. The pivot assembly includes a collar member 10 formed as a part of the second body portion, and a corresponding axle member 15 formed as a part of the first body portion and shaped to be intimately received within the collar member. The axle member is a generally cylindrically shaped projection extending outwardly of a surface of the first body portion, the longitudinal axis of the axle member so shaped defines (and coincides with) the axis of rotation "A" about which the second body portion may be pivotally moved relative to the first body portion.

The collar member presents an inwardly-facing concave annular surface (not shown) which circumscribes and opposes curved convex outer surface parts of the axle member when the latter is received within the former in use. The collar member is shaped to allow it to be slid over opposing curved outer parts of the received axle member both rotationally around the axis "A" of the axle member and longitudinally along the direction of that axis. The first body portion 60 defines the aforesaid outwardly presented abutment surface 5 concavely shaped to reciprocally correspond with the convex shape of the channel base of the hand rail 1 to which it is designed to be abutted in use. In assembled form, the second body portion 61 is pivotable in the direction "X" relative to the first body portion 60. This pivotability enables the baluster post 7 to be interconnected to the hand rail 1 at any one of a large range of interconnection angles/orientations.

One or more apertures 19 are arranged within the abutment portion 8 of the first body portion 60 either side of the axle member 15 and pass from the upper exposed surface of the abutment portion through to the concave abutment surface 5 in use and are arranged to receive and house fixing screws via which the first body portion may be fixedly abutted to the hand rail 1 in use. As an alternative to the use of screws 18 as fixing means for the first body portion, nails or adhesives may be employed additionally or alternatively.

Figure 4 illustrates a connector device being part of the stair rail apparatus according to a further embodiment of the present invention. The connector device 20 of this alternative embodiment is arranged to be connected to the end of a hand rail (or alternatively a shoe rail) of the stair rail apparatus. The abutment portion 8 of the connector device forms a sleeve shaped to receive the end of the hand rail 1, including the channel 2, whereby the inner sleeve surface 41 defines, at and between two separate abutment surfaces 5, a recess shaped to receive the projecting channel base surface.

The sleeve shape of the abutment portion defines a socket for receiving the hand rail end. A fixing aperture 43 is provided within the body of the connector device 20 extending from the outer surface thereof to the inner surface of the socket defined by the sleeve and shaped to receive and house a fixing screw for the purposes of fixing the received hand rail end within the socket formation of the sleeved abutment portion 41. Attachment means (not shown) mayv be provided at other parts of the connector device 20 for permitting attachment thereto of other hand/shoe rail members or baluster posts (or both) .

The abutment portion 8 of the connector device defines two separated abutment blocks 40 which each project inwardly from the inner sleeve surface 41 of the connector device and which each present a concave abutment surface 5 shaped to reciprocally match and receive respective parts of the convex channel base 2 of the hand rail 1 when the former and latter are connected.

The abutment blocks 40 extend substantially in parallel with each other along the direction of the symmetry axis of the sleeve shape 41 of the abutment portion 8 and are circumferentially separated upon the inner sleeve surface 41 such that when one abutment block abuts the channel surface 2 at or adjacent a channel corner 4 thereof the other abutment block most distant from it simultaneously abuts the channel surface at or adjacent the opposing channel corner 4 thereof. In the present example only two abutment blocks 40 are provided, however, additional intermediate abutment blocks may be provided thereby defining additional separate abutment surfaces, or one single continuous abutment surface may be provided (e.g. spanning the whole width of the received channel base surface) in place of the plurality of separate abutment surfaces illustrated in figures 4 to 6.

Figure 5 illustrates a further example of a connector device 50 according to a yet further embodiment of the stair rail assembly of the present invention. In this further embodiment the connector device comprises two abutment portions each defining a sleeve shaped to receive the end of a hand/shoe rail in exactly the same manner as the sleeve shaped abutment portion illustrated in figure 4 is arranged to receive such components. Consequently like items as between figures 4 and 5 have been assigned like reference numerals for the purposes of consistency and the reader is referred to the text describing figure 4 for any description of the features of the connector device of figures 5. The connector device 50 of figure 5 provides two sleeve-shaped abutment portions which extend from the body of the connector device 50 in substantially perpendicular directions. This enables the connector device 50 to interconnect one hand/shoe rail at substantially right-angles to another hand/shoe rail. Of course, other interconnection angles may be provided simply by appropriately modifying the relative angles at which the two sleeve-shaped abutment portions extend from the connector device 50.

In each of the connector devices 20 and 50 of figures 4 and 5 the wall of the sleeve has an access opening 42 formed within it adjacent the abutment blocks 40, the opening extending along the sleeve wall in the direction of the channel which will abut the abutment blocks 40 in use. The access opening 42 is arranged to expose those parts of the channel 2 received by the sleeve in use which would otherwise be covered by the sleeve wall were the access slot 42 absent. The access slot permits access to the base of the channel by the abutment portion 8 (and abutment surface 5) of an abutment portion of the variety illustrated in figures 1 and 2 having an outwardly presented abutment surface 5. The access opening 42 according to the present embodiments is a slot extending into the sleeve wall 41 from the outermost peripheral rim thereof. In alternative embodiments the access opening may be an aperture formed within the wall rather than a slot extending into it. The access opening enables the connector device of the variety illustrated in figure 1 or 2 to be positioned in close proximity to a connector device of the type illustrated in figures 4 to- 6 when the former and the latter are mutually connected to a common hand/shoe rail in use such as is schematically illustrated in the cross-sectional view of figure 6.

Referring to figure 6 a hand rail 1 is received within the sleeve-shaped socket 41 of the connector device 20 of figure 4 such that the abutment surface 5A of each of the two abutment blocks 40 abuts the convex channel base surface 2 adjacent a channel wall 3 and a channel corner 4. Simultaneously, the abutment surface 5B of the abutment portion 8 of the first body portion 60 of the pivotable connector device 9 of figure 3 is abutted to the convex channel base surface 2 of the hand rail 1 at parts of that channel surface which are exposed by (and surrounded by) the access opening 42 formed within the sleeve wall of the socket-shaped connector device 20.

It is to be noted that modifications and variations, such as would be readily apparent to the skilled person, may be made to the embodiments described herein without departing from the scope of the present invention.