EP2546450A2

EP2546450A2 - Apparatus, system and method for joining sub-frame members

Info

Publication number: EP2546450A2
Application number: EP12176208A
Authority: EP
Inventors: Peter Dyer; Mark Beaumont
Original assignee: Dempsey Dyer Ltd
Current assignee: Dempsey Dyer Ltd
Priority date: 2011-07-13
Filing date: 2012-07-12
Publication date: 2013-01-16
Also published as: EP2546450A3; GB2492815A; GB201112021D0

Abstract

Embodiments of the invention relate to an apparatus comprising: a first and second sub-frame members for framing a pane, each respectively comprising a first and second plurality of walls defining a first and second hollow cavities therethrough and each having respectively a first and second open end configured to receive therein a first and second protrusion of a means for joining the sub-frame members together. A least one of the first plurality of walls is a first external wall and at least one of the second plurality of walls is a second external wall. At least a part of the first and second external walls are configured to abut against one another in the form of a butt joint when in a joined condition.

Description

FIELD OF THE INVENTION

Embodiments of the present invention relate to: an apparatus, a system and method for joining sub-frame members. In particular, though without prejudice to the foregoing, various, but not necessarily all, embodiments relate to joining UPVC sash frame members for a UPVC window sash or door sash.

BACKGROUND TO THE INVENTION

A sash frame is a sub-frame of a window that is itself framed by and movably coupled to an outer frame which is fixed for example to a wall. The sash frame is movable within the outer frame so as to enable opening and closing of a window sash, e.g. by the sash frame being connected to the outer frame via a sliding hinge or tilting mechanism.
Typically, for unplasticized Polyvinyl Chloride (UPVC) sashes, a hot weld is used to join two UPVC sash frame members together to form a mitred corner joint of the sash. This joining mechanism involves the making two 45 degree angled cuts on each sash frame members to create a 90 degree angle corner of a sash frame. However, such a mitred joining mechanism results in a corner of the sash frame having a visible 45 degree angle weld join. Moreover, the use of hot welding is skill and labour intensive. Other joining mechanisms require a cover or end cap in order to conceal the inner hollow chamber of a sash frame member.
The listing or discussion of a prior-published document or any background in this specification should not necessarily be taken as an acknowledgement that the document or background is part of the state of the art or is common general knowledge. One or more aspects/embodiments of the present disclosure may or may not address one or more of the background issues.

BRIEF DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION

According to various, but not necessarily all, embodiments of the invention there is provided an apparatus comprising:

first and second sub-frame members, the first sub-frame member comprising a first plurality of walls at least some of which define a first hollow cavity, and the second sub-frame member comprising a second plurality of walls at least some of which define a second hollow cavity;
means for joining the first and second sub-frame members together in a joined condition, the joining means comprising a first protrusion and a second protrusion;
wherein the first sub-frame member is configured to receive the first protrusion at a first end of its first hollow cavity;
wherein the second sub-frame member is configured to receive the second protrusion at a second end of its second hollow cavity;
wherein at least one of the first plurality of walls is a first external wall and at least one of the second plurality of walls is a second external wall, and
wherein the first and second plurality of walls are configured such that the first and second external walls abut against one another so as to form a butt joint when in the joined condition.

Advantageously, this enables a sub-frame member mate or join to be effected via mechanical joining means wherein the joining means itself is concealed and hidden from view by the first and second external walls of the sub-frame members when mated together. Furthermore, joined sub-frame members form a corner joint that has the visual appearance of a butt joint (as opposed to a mitre joint). This enables a cleaner and more aesthetically pleasing look of joint to be possible.
This provides the advantage of an increase of the design flexibility and structural strength of a sub-frame member joint. Also, the joining of the sub-frames members and the assembly of the sub-frame is simplified as the joints may be effected without requiring a hot weld to be performed.
The first and second external walls may define a first plane, wherein the joining means is concealed when viewed from a first direction perpendicular to the first plane. The first direction of view may correspond to a direction of view that is predominantly visible during use, i.e. when the apparatus is installed in a window sash and viewed by a user face on when the window sash is in a closed position. In one embodiment of the invention, the joining means is exposed and visible from second and third directions perpendicular to the first direction. The exposed sides of the joining means may be configured to match a profile or comprise attributes corresponding to a profile of attributes of the sub-frame members. For example, where the sub-frame member comprises a euro groove, the joining means may likewise comprise a similar groove along its exposed sides.
In another embodiment of the invention, at least one of the first plurality of walls is configured to overlap the second hollow cavity end so as to cover and hide from view the second hollow cavity as well as a part of the joining means when in a mated condition. Likewise, at least one of the second plurality of walls is configured to overlap the first hollow cavity end so as to cover and hide from view the first hollow cavity as well as the remaining visible part of the joining means when in a mated condition. Such further embodiments also enable a cleaner and more aesthetically pleasing look of joint to be possible, especially wherein the covering walls are exterior walls provided with an aesthetic outer surface design.
According to various, but not necessarily all, embodiments of the invention there is provided a system comprising the apparatus as set out above and a pane at least partially framed by the first and second sub-frames. The system may be a door sash, a window sash, or a UPVC window sash.
According to various, but not necessarily all, embodiments of the invention there is provided a method comprising:

configuring a first and a second sub-frame member such that:
- a first protrusion of a means for joining the first and second sub-frame members together can be received into a first end of a first hollow cavity of the first sub-frame member when in a joined condition, and
- a second protrusion of the joining means can be received into a second end of a second hollow cavity of the second sub-frame member when in the joined condition; and
configuring the first and second sub-frame members such that:
- at least a part of a first external wall of a first plurality of walls of the first sub-frame member, and
- at least a part of a second external wall of a second
- plurality of walls of the second sub-frame member, abut against one another so as to form of a butt joint when in the joined condition.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of various examples of embodiments of the present invention reference will now be made by way of example only to the accompanying drawings in which:

Figure 1A schematically illustrates an embodiment of the present invention in an unassembled form;
Figure 1B schematically illustrates the embodiment of Figure 1A in a joined condition;
Figures 1C, 1D and 1E schematically illustrate another embodiment in an unassembled form, a partially assembled form and an assembled form respectively;
Figures 2A and 2B schematically illustrate partial cross-sectional views of embodiments of the invention;
Figures 3A and 3B schematically illustrate a side-on view and partial cross sectional view respectively of a further embodiment of the invention;
Figures 4A and 4B schematically illustrate another embodiment in an unassembled form and a partially assembled form respectively;
Figure 4C schematically illustrates the embodiment of Figure 4B from an alternative perspective in a joined condition;
Figures 5A and 5B schematically illustrate a side-on view and an enlarged cross sectional view respectively of pre-milled sub-frame members for use in embodiments of the invention;
Figures 5C and 5D schematically illustrate a side-on views of an embodiment in an unassembled form and partially assembled form respectively; and
Figures 6A and 6B schematically illustrate side-on views of a window sash formed from the embodiment of Figure 5D in a closed position and an open position respectively.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION

The Figures illustrate an apparatus 10 according to embodiments of the present invention which comprises:

first 201 and second 202 sub-frame members, the first sub-frame member comprising a first plurality of walls 205a-d at least some of which define a first hollow cavity 203, and the second sub-frame member comprising a second plurality of walls 207a-d at least some of which define a second hollow cavity 204;
means 100 for joining the first and second sub-frame members together in a joined condition, the joining means comprising a first protrusion 101 and a second protrusion 102;
wherein the first sub-frame member 201 is configured to receive the first protrusion 101 at a first end 208 of its hollow cavity 203;
wherein the second sub-frame member 202 is configured to receive the second protrusion 102 at a second end 209 of its hollow cavity 204;
wherein at least one of the first plurality of walls is a first external wall 206a and at least one of the second plurality of walls is a second external wall 207a, and
wherein the first and second plurality of walls are configured such that the first and second external walls abut against one another so as to form a butt joint when in the joined condition.

In the figures, only the functional components that are necessary for describing the operation of the apparatus are mentioned. For example, where the sub-frame member is a window sash member, means for receiving and securing a pane of glass to the sash frame member and means for engaging the sash-frame member with an outer frame have not been shown (though are discussed below with reference to Figure 5B).
Figure 1A schematically illustrates an apparatus 10 according to an embodiment of the invention in an unassembled form, namely wherein protrusions 101 102 of a means for joining sub-frame members 100 are not inserted into and securely mated with the open end hollow cavities 203 204 of the sub-frame members 201 202 to form a butt type corner joint (which is shown in an assembled form in Figure 1B).
The means for joining sub-frame members 100 provides a joining device that mechanically joins and rigidly fixes the sub-frame members 201 202 together so as to provide a secure structural connection between them. The first and second protrusions project out at a first direction and a second orthogonal direction so as to provide and "L" shaped joining means for providing re-enforcement of the butt type corner joint of sub-frame members. The angle θ between the first and second directions is substantially 90 degrees.
The means for joining sub-frame members 100 may be formed via injection moulding and/or made from a material such as UPVC.
The sub-frame members 201 202 are support members that are configured to be able to support a panel or pane (not shown), such as a pane of glass, translucent material, mirror or other object to be held within the frame. The sub-frame members additionally comprise means for receiving and securing panes (as shown in Figure 5B). A sub-frame itself is supported by an outer frame (not shown in Figure 1A, but shown for example in Figure 6A) and connected to the outer frame via a movement mechanism permitting movement of the sub-frame relative to the outer frame. The sub-frame members additionally comprise means for engaging with the outer frame (not shown).
The sub-frame members 201 202 may, for example, be elongate extruded hollow cylinders with walls 205a-d, 207a-d defining an internal hollow chamber/cavity therethrough. At least one of the walls, e.g. 205a 207a, of each sub frame member is an external/exterior wall, for example a wall of the sash frame member which is predominantly visible during normal use, i.e. the wall whose surface is parallel to the pane framed by the sub-frame members which is facing and viewed by an observer when the window sash is closed. The external walls 205a 207a may define a first plane (X-Y plane) which is parallel to a plane of a pane framed by the sub-frame members. A first direction (Z) may be defined as being perpendicular to the first plane. The first direction of view may correspond to a direction of view that is predominantly visible during use, i.e. when the apparatus is installed in a window sash and viewed by a user face on when the window sash is in a closed position.
Each sub-frame member may also have an opposing external wall, e.g. 205c, 207c, such that, for example, the external walls of the sub-frame members may be those visible when viewing the window sash from either side, i.e. from inside or outside of a building. The sub-frame members may be formed by extrusion of extrusive material such as PVC, UPVC or Aluminium. In various but not necessarily all embodiments, the sub-frame members are casement members or sash frame members of a window sash frame, window sash or door sash. More particularly, in certain embodiments, the sash members are Unplasticized Polyvinyl Chloride (UPVC) (such as is available from Deceuninck NV and for example with Deceuninck's 2800 series and part number P2825) or domestic casements complying with BS7950.
Figure 1B schematically illustrates the embodiment of Figure 1A in an assembled form, namely wherein the first and second protrusions have been inserted into the first and second hollow cavities of the first and second sub-frames respectively. As is shown in this Figure, according to embodiments of the invention, the joint of sub-frame members have the visual appearance of a butt joint.
The sub-frame members 201 202 comprise a plurality of walls 205a-d defining the hollow cavity therethrough 203, which are configured so as to be able to receive a protrusion and securely mate therewith. The cavity may be at a longitudinal end of the sub-frame member and may extend along the entire length of the sub-frame member.
The end portions of the first and second sub-frame members are configured so as to abut against one another to provide the visual appearance of a butt joint. At least a portion of an external wall 206a (shown in outline) is configured such that, when the protrusion 101 is inserted into the cavity 203, the side wall portion 206a at least partially provide an overlap or cover so as to conceal at least part of the joining means 100 when viewed from the first direction (Z) perpendicular to the first plane.
The remainder of the joining means, such as its protrusion 102, is concealed by the external wall 207a which abuts against the external wall 206a at 90° so as to form a butt type corner joint. Accordingly, in embodiments of the invention, both the first end of the first sub-frame member as well as the second end of the second sub-frame member are cut at 90° to their longitudinal direction so as to enable abutting of the ends to form a butt type corner joint (c.f. a mitre joint which involves two 45° angle cuts at the respective ends of the sub-frame members).
In the embodiment of Figures 1A and 1B, the end portions of the sub-frame members are further configured so as to conceal the joining means from a second direction (X, i.e. conceal from view from the left hand side viewpoint) which is perpendicular to the first direction (Z) as well as a third direction (Y, i.e. conceal from view from a top down viewpoint) which is also perpendicular to the first direction (Z).
In this embodiment, at least a portion 206b of one of the side walls of the first sub-frame member 201 is configured so as to provide an overlap or cover so as to conceal the interior hollow cavity 204 of the second sub-frame member 202 when viewed from the second (X) direction. Likewise, at least a portion 202b of one of the side walls of the second sub-frame member 202 is configured so as to provide an overlap or cover so as to conceal the interior hollow cavity 203 of the first sub-frame member 201 when viewed from a third (Y) direction.
Such configuration of the walls may comprise: cutting, milling, scribing or otherwise removing portions of side walls, i.e. removing portions of the other side wall 205d, to define a particular profile, dimension and shape which can accommodate the joining means and its first protrusion whilst also providing portions of its side wall 206a-c that at least partially cover the joining means as well as the internal hollow cavity of the other sub-frame member when joined together so as to conceal the joining means and the hollow cavity from view. Accordingly, embodiments of the invention provide a joint which has the visual appearance of a butt joint, but which is reinforced with the joining means.
A cutting profile 206a and 206c is provided to each opposing side walls 205a and 205c of the sub-frame member 201 so as to provide an overlap or cover to the joining means when within the opposing side walls 205a 205c thereby concealing the joining means within.
Where the sub-frame member forms part of a window sash, advantageously, such a configuration hides the joining mechanism 100 of the window from both readily viewable sides (i.e. +Z and -Z directions) for example when viewed from both inside and outside of a room) as well as providing a joint which is visually pleasing with the appearance of a traditional looking butt joint.
The first and second protrusions 101 102 are configured so as to be insertable into their respective first and second cavities 203 204, i.e. the first and second protrusions may be dimensioned so as to mate and inter-engage with the first and second hollow cavities respectively. The fit of the mate may be sufficiently tight fitting that frictional forces can be used to hold the protrusion in place. Alternatively, further fixing means may be employed, such as adhesives or a cold weld.
In Figures 1A and 1B, extending wall portions 206b and 202b are provided to overlap/cover the inserted joining means 100 so that it is hidden from view from a left-hand side-on view (X) as well as a top-down view (Y). Figures 1C-E show an alternative embodiment of the invention in which no such wall portions extensions 206b and 202b are provided such that a joining means 100' is exposed on its leftmost and topmost sides.
The joining means 100' means comprises an intermediary portion 103 disposed between the first and second protrusions 101 102. The first and second protrusions 101 102 protrude or extend out from the intermediary portion. The joining means is configured and dimensioned such that, when its first and second protrusions 101, 102 are inserted into the sub frame members 201 202 to provide a butt joint, the intermediary portion 103 is concealed within wall extension portions 206a and 206b such that the joining means is not visible from the first (Z) direction perpendicular to the (X-Y) plane. However, since there are no extended wall portions to conceal the joining means from a left hand side (X) viewing direction or a top side (Y) viewing direction, the joining means is visible from these X and Y directions as clearly shown in Figure 1E. However, it is to be noted that during typical use of such embodiments when installed in a sash window, whilst the sash window is closed the left hand side X and top side Y would not be visible to a user. Only front and back faces 207a, 205a and 205c, 207c (from +Z and -Z directions) would be visible and the joining means would be concealed from view from these (+Z and -Z) directions behind wall portions 206a and 206c of the butt joint.
The upper Y surface and X side surface of the joining means 100' may be configured to match the profile or attributes of the respective walls 205b and 207b. Advantageously, this enables a continuity of the profile/attributes of the walls 205b and 207b to extend into the joining means. For example, the walls 205b and 207b might be profiled to include a eurogrove profile/ central channel 216, 213 as part of its extruded PVC housing which acts as a locater for a locking system (such as shown with respect to housing portion 514 of Figure 5B) or to house means for engaging with an outer frame. The continuity of the housing portion 216 and 213 into and along the exposed sections of the intermediary portion 103 provides a continuity of the housing portion even where the end sections of the sub-frame members have been milled out to make room for the joining means. This allows the butt joint corner to have continuity of a wall's profile/housing means, even at extremes of the corner. The joining means may further comprise other attributes of the sub-frame members, and in particular parts of the sub-frame members which have been removed/milled out to make room for the joining means, such as sealing means e.g. a gasket, to create a seal between the sub-frame member and a outer frame and a locking system. Advantageously, such features provide a butt type corner joint that enables enhanced compatibility with various locking systems and helps to provide a more secure and robust sash frame.
Figures 1A-B and 1C-E each show a single corner joint, namely an upper left-hand corner joint of a sash frame. It will be appreciated that a plurality of similar joining arrangements may be provided at each end of the sub-frame members and additional sub-frame members may be provided so as to form an entire sub-frame. For example, a lower left-hand corner as well as both an upper and lower right-hand corner joints may be provided to form a rectangular sub-frame that holds a planar material, such as a pane of glass therein. The sub-frame itself is supported and movably mounted in an outer frame.
Figure 2A schematically illustrates a possible partial cross-section 210a of one of the protrusions of Figure 1A along the line A-A of Figure 1 and a partial cross-section 210b of one of the sub-frame members 202 along the line B-B. The cross sectional view of the sub-frame omits, for example, a cross sectional view of the sub-frame's means for receiving and securing a pane to the sub-frame and the sub-frame's means for engaging with an outer frame (see Figure 5B in this regard).
The cross-sectional profile 210a of the protrusion is configured and dimensioned such that it is able to be inserted into an end of the sub-frame member and securely mate with the hollow cavity defined by the walls of the sub-frame member 205a-d.
The protrusions and their cross section are dimensions so as to fit within the hollow cavity sufficiently tightly that the protrusion is rigidly and securely held within the cavity via frictional forces to provide a mechanical joint. Additionally or alternatively, other fixing means could be employed to hold the protrusion rigidly and securely in place, such as adhesives or a cold weld of UPVC. Such adhesives could be applied to sections of the protrusion 21 1 a 211 b which are in physical contact with the interior of the walls 205a 205c of the sub-frame member.
In figure 2A the cross-sectional shape of the protrusion, namely an "I" shape, does not precisely correspond to the cross-sectional shape of the sub-frame member, namely a rectangular shape, but nevertheless, the protrusion's cross-sectional shape is configured and dimensioned so as to provide a secure tight fitting mate when inter-engage with the hollow cavity.
In order to strengthen the bond between the protrusion and the cavity when mated, the protrusion could be configured so as to maximise its external surface area that is in contact with the interior of the hollow cavity, also the length of the protrusion could be suitably adjusted.
Figure 2B, shows another possible cross-sectional shape combination of a protrusion and sub-frame member respectively 212a 212b that may be employed with embodiments of the invention. As will be apparent, a variety of complex cross-sectional profiles and shapes may be employed.
Variables that such as:

the surface area of contact between the protrusion and internal walls of the hollow cavity,
the length of the protrusion,
the thickness of the walls of the sub-frame member,
the milling profile of the walls of the sub-frame member, and
colour, design and texture of the walls of the sub-frame member may be varied as appropriate.

Figure 3A schematically illustrates a side-on view of a further embodiment 300 in which the first protrusion 301 of the joining means 300 comprises a plurality of protrusions elements 301 a-c. The sub-frame members 311 312 likewise has a plurality of hollow cavities extending therethrough 304a-c. Each of the plurality of protrusions elements 301a-c (and 302a-c of the second protrusion 302) is configured to be inserted into a respective plurality of hollow cavities of their respective sub-frame member.
Figure 3B schematically illustrates a possible cross-section of the protrusions elements 301a-c along the line A-A of Figure 2A and a partial cross-section the sub-frame member 311 along the line B-B (again the cross sectional view of the sub-frame omits, for example, a cross sectional view of the sub-frame's means for receiving and securing a pane to the sub-frame and the sub-frame's means for engaging with an outer frame.
Alternatively, where the sub-frame comprises a plurality of hollow cavities 304a-c, a plurality of joining means could be used (as shown and discussed with reference to Figures 5C and 5D) instead of providing a single joining means whose first and second protrusions comprise a first and second plurality of protrusion elements.
Figure 4A schematically illustrates another embodiment of a joining means 400 for joining sub-frame members 201 202. The joining means comprises an intermediary portion 403 disposed between the first and second protrusions 401 402. The first and second protrusions 401 402 protrude or extend out from the intermediary portion.
The cross-sectional dimensions of the intermediary portion 403 in a given plane (such as a plane perpendicular to the y or x axis or a plane perpendicular to a direction of projection of a protrusion) are different to the cross-sectional dimensions of the first and second protrusions respectively 401 402. Whilst the first and second protrusions are dimensions so as to fit within a hallow cavity 203 defined by walls 205a-d of a sub-frame member 201, the intermediary portion 403 is configured such that it is unable to fit within the hallow cavity 203, i.e. the cross sectional dimensions of the intermediary portion are greater that the cross sectional dimensions of the hollow cavity.
The intermediary portion 403 is dimensioned and an end 206 of the sub-frame member 201 is configured such that the protrusion 401 is able to be inserted into the cavity 203 and a side 403a of the intermediary portion 403 is at least partially overlapped or covered by an end portion 206a of one of the side walls 205a. The intermediary portion 403 and the end of the sub-frame member are further configured such that, an opposite side of the intermediary portion 403c is at least partially overlapped by an end portion 206c of a wall 205c of the sub-frame member 201. Also, the intermediary portion 403 and the end of the sub-frame member are further configured such that a side of the intermediary portion 403b, opposite to a side from which the second protrusion extends, is at least partially overlapped by an end portion 206b of a wall 205b of the sub-frame member 201.
Likewise, the intermediary portion 403 and an end 202b of the other sub-frame member 202 are configured such that a side of the intermediary portion 403e, opposite to a side from which the first protrusion extends, is at least partially overlapped by an end portion 202b of a wall of the sub-frame member 202.
The provision of extending end wall portions 206a 206b 206c and 202b to at least partially cover sides of the intermediary portion may be effected by removing end portions from other side walls of the sub-frame member such that the extended portions are integral to their respective wall. Also, the thickness of the side walls 205a-d at the end 206 may be adapted so as to accommodate the intermediary portion therein.
Figure 4B schematically illustrates the embodiment of Figure 4A in a partially assembled form, namely wherein the first protrusion 401 has been inserted into its respective hollow cavity 203 and the sides 403a 403b and 403c of the intermediary portion are concealed behind end walls portions 206a, 206b and 206c thereby hiding the intermediary portion when viewed from either direction along the z axis.
The dimension of the intermediary portion 403 and or the walls 205a-d are configured such that the intermediary portion abuts against a top edge of the walls 205a 206c, i.e. the top of the walls provide a rim on which the intermediary portion rests preventing it from entering the hollow cavity 203.
Figure 4C schematically illustrates the embodiment of Figures 4A and 4B in an assembled form from an alternative perspective, namely when viewed along the x axis. This shows that the joined sub-frame members have the visual appearance of a butt joint. The end portions 206a-c and 202b configured so as to cover and conceal the intermediary portion 403 and the respective interior cavities 204 and 203 when viewed from either direction along the x, y or z axis. End portions of the wall 205d and end portions of the walls of the sub-frame member 202 have been removed so as to enable accommodation and reception of the joining means 400 and its concealment between the end wall portions.
Figure 5A schematically illustrates a side-on view of sub-frame members 501 502 that could be used in embodiments of the invention. The sub-frame members are shown pre-milled, i.e. before they have been cut to a desired profile for receiving a joining device and inter engaging with one another to form a corner joint. The pre-milled sub-frame members are elongate hollow cylindrical members.
The sub-frame members 501 and 502 are composite sub-frame members that comprise sub-frame member portions 501 a-c and 502a-c, namely external perimeter sub-frame member portions 501 a 502a, main sub-frame member portions 501 b 502b and internal perimeter sub-frame member portions 501 c 502c. The sub-frame members can either be formed from 3 separate framing portions affixed together (e.g. one could consider each sub-frame member portion as being a sub-frame member in its own right) or the sub-frame member can be integrally formed, e.g. via extrusion, so as to comprise all the sub-frame member portions.
Figure 5B schematically illustrates an enlarged cross-sectional view of the sub-frame member 501 of Figure 5A along the line A-A. The sub-frame member comprises a plurality of walls, some of which, 505a-h, define a plurality of hollow cavities 504a-c. Such hollow cavities and their respective walls form one of the sub-frame member portions 501a-c.
The sub-frame members 501 502 may include design or aesthetic features on their external walls 505a, 505e and 505g, such as curved walls 505e 505g, chamfers 506 and may be provided with an external colour, texture and appearance, for example so as to resemble a wood-like appearance.
Figure 5B also shows aspects of the sub-frame member that enable it to receive and secure a pane as well as engage with an outer frame. Housing portions 510 and 511 are provided to house means for receiving and securing panes to the sub-frame. The means for receiving and securing panes may comprise sealing means e.g. a gasket 512, to create a seal between the pane and the sub-frame as well as a securing means (not shown) e.g. a clipping system, for securing the pane to the sub-frame member. Furthermore, additional housing portions 513 and 514 are provided to house means for engaging with an outer frame. Such means may comprise additional sealing means e.g. a gasket 515, to create a seal between the sub-frame member and the outer frame and a locking system (not shown).
Figure 5C schematically illustrates a side-on view of the sub-frame members 501 502 having been configured so as provide complementary shapes to one another, i.e. the ends of the sub-frame members that are to be joined together have been profiled so that, when the ends are bought together form a corner joint, the walls 505e 505a and 505g facing one side of the sub-frame member 501 abut in a tessellating manner (i.e. such that there is no overlap of the walls of gaps between the walls) the respective walls of the other sub-frame member 502.
The complementary shapes of the milled profiles of the ends of the sub-frame members enable them to inter engage with one another with no overlaps or gaps, thereby providing a cover over the joining means concealing it and the internal cavities of the sub-frame members from view. More particularly, at least one of the plurality of walls of a first sub-frame member is configured so as to be mutually complimentary to a configuration of respective at least one of a plurality of walls of the second sub-frame member such that, when the respective walls of the two sub-frame members are brought together, the walls do not overlap with one another or have any substantial gaps therebetween and cover the joining means and the internal cavities of the sub-frame members.
In the embodiment shown in Figure 5C, each of the sub-frame member portions 501 a-c and the sub-frame member portions 502a-c have been configured to have complementary inter engaging shapes. The external sub-frame member portions 501 a 502a have been milled to have two complementary 45 degree angle cuts. The main sub-frame member portions 501 b 502b have been milled to as to provide a rectangular projection on one sub-frame member and a corresponding rectangular recession on the other sub-frame member. Finally, the interior perimeter sub-frame member portions 501 c and 502c have also been milled to have two complementary 45 degree angle cuts.
It will be appreciated that the end portions of respective sub-frame members that are to be joined can be cut in a wide variety of complementary interlocking, tessellating shapes and angles such that, when joined and abutting one another, they fit together with no overlaps or gap so as to conceal each sub-frame member's hollow cavity and the joining device inserted therein.
Figure 5D schematically illustrates a side-on view of the embodiment of Figure 5C in a partially assembled form in which the first protrusions 401 a-c have been inserted into their respective hollow cavities 504a-c. The intermediary portions are variously concealed by end portions of side walls 505e 505a 505g. A side of each intermediary portion 403a and 403c is partially concealed by the angled end portions of side walls 505e and 505g respectively. A side of the intermediary portion 403b is substantially entirely concealed by wall portion 505a. (It is to be appreciated that were the joining device 400b initially to be inserted into the sub-frame member portion 502b, then the side of the intermediary portion 403b would be substantially entirely revealed /exposed and not concealed by an end portion of a side wall of the sub-frame member portion 502b. Instead, coverage of the side of the intermediary portion 403a would be provided by the end portion of side wall 505a of the sub-frame member portion 501 b).
Figure 6A schematically illustrates a view of the embodiment of Figure 5C when installed as a window sash 600. Advantageously, this embodiment enables the provision of a UPVC sash frame corner joint having a butt joint (particularly with regards to the shape and configuration of the end portions of the sash frame sections 501 b and 502b) which, when using UPVC products whose external colour, texture and appearance is designed to resemble wood, provides a timber joint appearance. Whilst the main sash frame sections 501 b and 502b are configured in a butt joint type corner, the outer sash frame sections (501 a and 502a) and inner sash frame sections (501 c and 502c) are configured in a mitre joint type corner. The provision of such mitre joint appearance in combination with the butt joint appearance is applicable to various of the described embodiments, including the embodiments described with regards to Figures 1C-1E.
The window sash 600 comprises sash frame members 501 502 joined via a joining device as described above (not shown). The sash frame members frame and support a pane of glass 601.
The sash frame itself supported within an outer frame 602 and is coupled thereto via a movement mechanism enabling the sash frame to move relative to the outer frame. The outer frame is securely and fixedly mounted to a wall 603.
Figure 6A shows the window sash in a closed position, whereas figure 6B shows the window sash in an open position as indicated by arrows 705 The sash frame window is hinged on its right-hand side (not shown) enabling the window sash to open and close.
Embodiments of the present invention also relate to a system comprising a plurality of joining means and sub-frame members as described above along with a pane framed by the sub-frame members. Furthermore, embodiments of the present invention also relate to a method of manufacture, assembly and use of the joining means, sub-frame member and system.
In the above description, the wording 'connect' and 'couple' and their derivatives/equivalents mean operationally connected/coupled. It should be appreciated that any number or combination of intervening components can exist (including no intervening components).
Features described in the preceding description may be used in combinations other than the combinations explicitly described.
Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not. Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.
Although various embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.
Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

An apparatus comprising:
first and second sub-frame members, the first sub-frame member comprising a first plurality of walls at least some of which define a first hollow cavity, and the second sub-frame member comprising a second plurality of walls at least some of which define a second hollow cavity;

means for joining the first and second sub-frame members together in a joined condition, the joining means comprising a first protrusion and a second protrusion;

wherein the first sub-frame member is configured to receive the first protrusion at a first end of its first hollow cavity;

wherein the second sub-frame member is configured to receive the second protrusion at a second end of its second hollow cavity;

wherein at least one of the first plurality of walls is a first external wall and at least one of the second plurality of walls is a second external wall, and

wherein the first and second plurality of walls are configured such that the first and second external walls abut against one another so as to form a butt joint when in the joined condition.
The apparatus as claimed in claim 1, wherein the first and second external walls are configured to conceal the joining means from a first direction when in the joined condition.
The apparatus as claimed in claim 1 or 2, wherein at least part of the joining means is exposed from a second direction, wherein the second direction is orthogonal to the first direction.
The apparatus as claimed in claim 3, wherein a profile of the exposed part of the joining means is configured to match a profile of one of the sub-frame members.
The apparatus as claimed in claim 4, wherein the profile comprises a grove along the sub-frame member.
The apparatus as claimed in any one of the previous claims, wherein at least one of the first plurality of walls is configured to cover the second end of the second sub-frame member when in the joined condition.
The apparatus as claimed in any one of the previous claims, wherein the cross-sectional dimensions of the first protrusion are configured such that the first protrusion is insertable into the first hollow cavity to mate therewith.
The apparatus as claimed in any one of the previous claims, wherein the first sub-frame member is an elongate hollow member and the first cavity is a cavity at a longitudinal end of the first sub-frame member which extends along the length of the hollow first sub-frame member.
The apparatus as claimed in any one of the previous claims, wherein the first sub frame member comprises a first plurality of cavities.
The apparatus as claimed in claim 9, wherein the joining means comprises a first plurality of protrusions configured to mate with the first plurality of cavities.
The apparatus as claimed in claim 9, further comprising a plurality of joining means each configured to mate respectively with the first plurality of cavities.
The apparatus as claimed in any one of the previous claims, wherein the first and second sub-frame members are configured to at least partially frame a pane.
A system comprising the apparatus as claimed in any one of the previous claims and a pane at least partially framed by the first and second sub-frames.
A system as claimed in claim 13, wherein the system is a door sash, a window sash, or a uPVC window sash.
A method comprising:
configuring a first and a second sub-frame member such that:
a first protrusion of a means for joining the first and second sub-frame members together can be received into a first end of a first hollow cavity of the first sub-frame member when in a joined condition, and

a second protrusion of the joining means can be received into a second end of a second hollow cavity of the second sub-frame member when in the joined condition; and

configuring the first and second sub-frame members such that:
at least a part of a first external wall of a first plurality of walls of the first sub-frame member, and

at least a part of a second external wall of a second plurality of walls of the second sub-frame member, abut against one another so as to form of a butt joint when in the joined condition.