COUPLING SYSTEM AND FURNITURE ITEM

TECHNOLOGICAL FIELD

The present disclosure relates to a coupling system for joining two structural members using a locking member. The disclosure further concerns a furniture item comprising the coupling system, an assembly comprising the coupling system and a kit of parts for the coupling system.

GENERAL DESCRIPTION

According to a first aspect of the present disclosure, there is provided a coupling system comprising: a first structural member comprising at least one of a first recess or projection and a pivot seat; a second structural member comprising the other one of the at least one first recess or projection, and at least one of a second recess or projection; and a locking member comprising a lever, the other one of the at least one second recess or projection and a pivot portion; wherein the first projection is configured to be received within the first recess, the second projection is configured to be received within the second recess and the pivot portion is configured to be received within the pivot seat; wherein the lever is pivotally displaceable between a locked position and an unlocked position; wherein in the locked position, the at least one second projection and second recess are in locked engagement, and wherein in the unlocked position, the at least one second projection is disengaged from the at least one second recess.

According to a second aspect of the present disclosure, there is provided a coupling system comprising: a first structural member comprising at least one of a first recess or projection and a pivot seat; a second structural member comprising the other one of the at least one first recess or projection, and at least one of a second recess or projection; and a locking member comprising a lever, the other one of the at least one second recess or projection and a pivot portion; wherein the first projection is configured to be received within the first recess, the second projection is configured to be received within the second recess and the pivot portion is configured to be received within the pivot seat; wherein, in use, when the first projection is received within the first recess and the pivot portion is received within the pivot seat, pivotal rotation of the lever causes the locking member to rotate about its pivot portion, bringing the second projection and second recess into reversible locking engagement, thereby engaging the first structural member and the second structural member.

Since the at least one first projection is configured to be received within the at least one first recess, the first and second structural member can be brought into assembly in an aligned manner and relative movement of the first and second structural members transverse to the direction of projection can be reduced.

Since in the locked position the pivot portion of the locking member is received within the pivot seat of the first structural member and the at least one second projection is received within the at least one second recess, the locking member provides a secure connection between the first and second structural members.

The first structural member can comprise a lateral member protruding from a tubular member. The second structural member can comprise a portion of a lateral surface support structure. Alternatively, the second structural member can comprise a lateral member protruding from a tubular member and the first structural member can comprise a portion of a lateral surface support structure.

With this arrangement the coupling system can be used to connect two transverse i.e. non-parallel structures or members.

Alternatively, the coupling system can be used to connect two parallel structures or members.

The second structural member and the locking member can be fitted to the first structural member from opposite sides of the first structural member.

The at least one of the first recess or projection can be located on an opposite side of the first structural member from the pivot seat.

With this arrangement the first structural member can be sandwiched or secured between the second structural member and the locking member which are locked together in the locked position by engagement of the at least one second projection and recess. Thus, the second structural member can be secured to the first structural member.

The at least one second recess can comprise at least one of a slot or a groove. While a slot passes entirely through the thickness of the second structural member or locking member, the groove is only partially recessed into the respective member in the thickness direction. The lever of the locking member can project away from the pivot portion. The other of the second recess or projection can be located on an arm of the locking member projecting from the lever. The arm can project from the lever at a portion of the lever adjacent or proximal to the pivot portion.

With this arrangement, applying a moment about the pivot portion by applying an appropriate force to the lever to rotate the lever causes a rotation of the arm about the pivot portion.

In an assembled configuration of the first structural member, the second structural member and with the locking member in the locked position, the outer surface of the locking member can be flush with and/or recessed into the outer surface of the first structural member. The outer surface of the locking member can comprise the lever.

With this arrangement, accidental unlocking of the coupling system can be prevented since it is not easy to accidentally operate, i.e. rotate, the lever to the unlocked position from the locked position. Furthermore, a smooth, continuous surface can be achieved which can be aesthetically beneficial.

Since the lever is on the outer surface, it can be easily reached to be operated.

The recess in the first structural member, in which the lever can be housed, can be larger than the size of the lever so as to allow a significant clearance fit. Such a significant spacing around the lever within the recess can allow an operator, such as a human operator, to use their fingers or another tool to pry open the lever, or rotate the lever to an unlocked position. Such an arrangement allows easy disassembly and reassembly of the coupling system.

The second structural member can comprise the at least one second recess, and the at least one second recess can take the form of at least one of an arcuate groove or slot, such that rotation of the lever of the locking member about the pivot portion causes arcuate motion of the at least one second projection along the at least one of an arcuate groove or slot.

Alternatively, the second structural member can comprises the at least one second projection, and the at least one second projection can take the form of an arcuate track, such that rotation of the lever of the locking member about the pivot portion causes arcuate translation of the at least one second recess along at least a portion of the at least one arcuate track. In any of the above arrangements, an arcuate groove, slot or a track which corresponds to the arcuate motion or translation of a portion of the locking member allows alignment and secure engagement to be achieved. Further, a groove, slot or track and corresponding projection or recess can be arranged to fittingly engage with one another thereby reducing or preventing accidental disengagement from one another.

End portions of the first and second structural members, which can comprise at least the at least one first projection and recess, can be arranged to be collinearly aligned when coupled. With this arrangement, a single assembly extending in a collinear manner, i.e. along the same straight line, can be achieved.

The at least one first projection can be arranged to be received within the at least one first recess by bringing the first and second structural members towards one another in a direction transverse to the collinear alignment. With this arrangement, the engaging of the at least one first projection and recess assists in preventing relative translation of the respective first and second structural members in a direction parallel to the collinear direction once the first and second structural members are engaged.

At least one of the first and second structural members can comprise end portions of larger structural members. Alternatively, or additionally, at least one of the first and second structural members can comprise lateral projecting portions of larger structural members.

With these arrangements, larger structural members can be connected, which larger structural members may extend along parallel, collinear or transverse axes.

In an assembled configuration of the first and second structural members, where the at least one first projection is received within the at least one first recess, the outer surfaces of the first and second structural members can form a flush continuous surface. With this arrangement, a smooth, continuous surface can be achieved which can be aesthetically beneficial.

In an assembled configuration of the first structural member and the locking member, the outer surfaces of the first structural member and the locking member can form a flush continuous surface. With this arrangement, accidental unlocking of the coupling system can be prevented since it is not easy to accidentally operate, e.g. rotate or bump or knock, the lever to the unlocked position from the locked position since it does not protrude from the first structural member. Furthermore, a smooth, continuous surface can be achieved which can be aesthetically beneficial. In some embodiments, as the lever reaches the fully closed or locked position, a clicking sound can be heard. Alternatively, or additionally, a snap-fit can occur between the locking member and one or more of the first structural member and the second structural member, to lock the lever semi-permanently in the locked position. Such a semi-permanent snap-fit can be reversed by application of sufficient force to the lever in a direction of rotation of the lever towards the unlocked position.

The at least one first projection and recess can have a corresponding form when viewed from a direction perpendicular to the direction of assembly thereof. Since the forms correspond, a good alignment between the first structural member and the second structural member can be achieved.

The form when viewed from the direction perpendicular to the direction of assembly can be narrower in a central portion thereof than at the edges thereof in a direction along an imaginary line lying in the plane of the form and passing through its center point. The form when viewed from the direction perpendicular to the direction of assembly can be hourglass shaped. With a centrally narrowed and/or hourglass shaped form, relative translation parallel to a plane of the form between the first and second structural members can be reduced and/or prevented, since the wider portion of the form of the projection cannot fit within the narrower portion of the form of the recess.

The coupling system can comprise at least one third recess and projection, each of the at least one third recess and projection being arranged on one of the first and second structural members. The third projection can be configured to be received within the third recess when the first and second structural members are brought together.

With this arrangement, further secure alignment between the first and second structural members can be achieved. For example, whereas a single projection and recess can result in the first and second structural members being subject to relative rotation, provision of one or more further projections and recesses can help prevent or reduce this, by providing further points of connection and/or engagement between the first and second structural members.

At least one of the at least one third recess may comprise corrugated sides on at least one surface arranged to provide an interference fit with the at least one third projection. With this arrangement, a secure fit between the first and second structural members can be achieved. The at least one third projection can be in the form of tapering wedge which narrows in the direction of projection. By providing a tapering arrangement, upon assembling the projection and the recess, initially a clearance fit is achieved, allowing smoother and easier joining, followed by gradual tightening of the members to arrive at a secure interference fit. Further, as the fit changes from a clearance fit to an interference fit, the members being connected can gradually achieve a desired alignment.

The at least one first recess and projection can be configured to have a clearance fit. With this arrangement, the first and second structural members can be more economically produced to a lower tolerance, while the locking member can provide the necessary tightening to achieve a secure connection. Alternatively, or additionally, since the first and second structural members can move slightly relative to one another, there will not be any resistance to the tightening of the locking member due to the first and second structural members being fixed in a slightly misaligned manner.

In the locked position, at least one of the at least one second recess and projection can be configured to have an interference fit. With this arrangement, the locking member can secure the first and second locking members to one another in a secure manner.

Any one or more of the first structural member, the second structural member or the locking member may comprise a polymer material e.g. a plastic. Any one or more of the first structural member, the second structural member or the locking member may be formed by injection molding, extrusion or other forming processes as would be understood by the person skilled in the art.

According to a third aspect of the present disclosure, there is provided a furniture item comprising the coupling system of any of the embodiments of the first or second aspect. The first structural member can comprise a lateral projection projecting from an upright tubular member, and the second structural member comprises a portion of a frame for supporting a shelf.

According to a fourth aspect of the present disclosure, there is provided an assembly comprising the coupling system of any of the embodiments of the first or second aspect.

According to a fifth aspect of the present disclosure, there is provided a kit of parts for the coupling system of any of the embodiments of the first or second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Fig. 1A shows a top perspective view of a coupling system in an assembled configuration;

Fig. IB shows an exploded view of the coupling system of Fig. 1A comprising a first structural member, a second structural member and a locking member;

Fig. 1C shows a cross-sectional view along the plane A-A in Fig. 1A of the coupling system of Fig. 1A;

Fig. 2A shows a top perspective view of the first structural member of Fig. IB;

Fig. 2B shows a cross-sectional view along the plane B-B in Fig. 2 A of the first structural member of Fig. 2A;

Fig. 2C shows a bottom perspective view of the cross-sectional view of Fig. 2B ;

Fig. 2D shows a plan view of the first structural member of Fig. 2A;

Fig. 3A shows a side view of the second structural member;

Fig. 3B shows a bottom perspective cross-sectional view along the plane C-C in Fig. 3A of the second structural member of Fig. 3A;

Fig. 4A shows a top perspective view of the locking member of Fig. IB;

Fig. 4B shows a plan view of the locking member of Fig. 4A;

Fig. 4C shows a rear view of the locking member of Fig. 4A, as viewed in the direction of the arrow D of Fig. 4A;

Fig. 5A shows a top perspective view of a furniture item comprising shelves and the coupling system of Fig. 1A;

Fig. 5B shows the furniture item of Fig. 5A, with the shelves removed;

Fig. 6A shows a top perspective view of a portion of the furniture item of Fig. 5A in a state of disassembly; and

Fig. 6B shows an enlargement of a portion of the furniture item as shown in Fig. 6A, the enlarged portion including a coupling system. DETAILED DESCRIPTION OF EMBODIMENTS

A coupling system 100 is shown in Figs. 1A-1C. The coupling system 100 comprises a first structural member 120, a second structural member 140 and a locking member 160. Each of these components will be described in turn in more detail below with reference to subsequent drawings.

As shown in Figs. 2A-2D, in this example, the first structural member 120 comprises a lateral projection which projects from an upright tubular member. However, the first structural member can comprise an end portion of a beam, strut or other component, a lateral projection from a structure or any other portion of a structure arranged to comprise any of the embodiments of the first structural member.

The first structural member 120 comprises a first recess 122 and a pivot seat 124. The first recess 122 is configured to receive a first projection of the second structural member 140 as described below. As shown in Fig. 2C, in this example the pivot seat 124 comprises two pivot axle recesses 124a arranged to receive pivot axles of the locking member 160, and a curved surface 124b configured for sliding contact with an outer surface of the pivot portion of the locking member 160 as described in more detail below.

In general, the first structural member may have any number of projections and/or recesses configured to be received within and/or receive opposing recesses and/or projections respectively in the second structural member. Each of the corresponding projections and recesses may be arranged for a clearance fit or an interference fit. While a clearance fit allows some movement in the joint which would allow for greater variation in tolerance of production of the structural members, an interference fit ensures a reduction of play between the connected structural members. Even if a clearance fit is provided between the projections and recesses of the structural members, a secure connection reducing relative translation and/or rotation can subsequently be achieved by the locking member of the coupling system as will be described in more detail below.

The first structural member 120 of the example in Figs. 2A-2D further comprises a third projection 126 and a fourth recess 128 that has opposing corrugated sides 128a. The opposing corrugated sides 128a of the fourth recess 128 form teeth for gripping a fourth projection as will be described in more detail below.

The first recess 122 and the fourth recess 128 are open to a first side A of the first structural member 120, and the third projection 126 projects from the first structural member 120 in the direction of the first side A. The curved surface 124b of the pivot seat 124 bounds in part a recess in the first structural member 120 which is open to a second side B of the first structural member 120 opposite from the first side A.

The first structural member 120 further comprises a lever receiving recess 132 adjacent to the pivot seat 124 and a through-bore 130 and passing from the second side B to the first side A of the first structural member 120, providing a passage from the lever receiving recess 132 to the first recess 122. As will described below, the through-bore allows physical contact between the locking member 160 and the second structural member 140.

Fig. 3A and 3B show the second structural member 140 of this example in more detail. As shown, the second structural member 140 comprises a first projection 142, a third recess 146 and a fourth projection 148. The first projection 142 is configured to be received within the first recess 122 of the first structural member 120 and the third recess 146 is configured to receive the third projection 126 of the first structural member 120.

The fourth projection 148 is configured to be received within the fourth recess 128, and comprises opposing sides 148a configured to be gripped by the opposing corrugated sides 128a of the fourth recess 128. The sides 148a of the fourth projection 148 are not parallel but rather are slightly relatively angled so that the fourth projection 148 tapers in the direction of projection. This allows initially a clearance fit between the fourth projection 148 and fourth recess 128 as the second structural member 140 and the first structural member 120 start to be brought into engagement. A clearance fit allows some play between the connected members and makes the initial connection easier to achieve as alignment need not be precise.

Subsequently, as the second structural member 140 and the first structural member 120 are brought closer and the fourth projection 148 moves further into the fourth recess 128, a tighter fit is achieved between the corrugated sides 128a of the fourth recess 128 and the fourth projection 148. In this manner, a tighter and/or interference fit can be achieved, thereby allowing a secure engagement between the first structural member 120 and the second structural member 140.

The first projection 142 comprises a hook-shaped end portion 142a partially surrounding an arcuate slot 141 passing through the first projection in a thickness direction T. In particular, the hook-shaped portion 142a of this example surrounds an upper side of the slot 141 and encloses an end-portion 141a of the slot 141, so as to partially surround an underside of the slot 141. The first projection 142 further comprises a main body portion 142b comprising an arcuate groove or channel 143 substantially concentric with the arcuate slot 141 and recessed into the main body portion 142b in the thickness direction T. Substantially concentric means that rotation of the locking member 160 about its pivot portion 164 allows two separate locking portions of the locking member 160 to translate simultaneously along the arcuate slot 141 and groove 143 respectively.

The slot 141 comprises an arcuate shape having a narrower enclosed end portion 141a than an open-end portion of the slot 141b. Similarly, the arcuate groove 143 has a wider open-end 143b and a narrower enclosed end-portion 143a. Such an arrangement allows initially a clearance fit between a portion of the locking member 160 and the slot 141 or groove 143 respectively as the locking member 160 and the second structural member 140 start to be brought into engagement.

Subsequently, as the locking member 160 is rotated and the portions of the locking member 160 slide along the slot 141 or groove 143 respectively, a tighter fit is achieved as the slot 141 and groove 143 narrow respectively towards the respective open-end portions 141b, 143b thereof. In this manner, a tighter and/or interference fit can be achieved, thereby allowing a secure engagement between the locking member and the second structural member.

Figs. 4A-4C show the locking member 160 in more detail. The locking member 160 comprises a lever 172 connected to and radially extending from a pivot portion 164. Projecting from the lever 172, adjacent to the pivot portion 164, is an arm 170 comprising (consecutively in a direction away from the lever 172) a first locking portion 161 configured to be received within the arcuate slot 141 and a second locking portion 163 configured to be received within the arcuate groove 143. The first locking portion 161 has a greater thickness in the thickness-direction T than the thickness of the second locking portion 163.

In this example, either or both of the first and second locking portions 161, 163 and the corresponding arcuate slot 141 and groove 143 can be considered to be the at least one second projection and recess, respectively.

Although in this example the first locking portion 161 and the second locking portion 163 are shown spaced apart from one another, it is also envisaged that in another example they may be adjacent to one another. Alternatively, or additionally, in another example, the order in which the first locking portion 161 and the second locking portion 163 are arranged along the arm 170 may be substituted. In these cases, the slot and groove would also be re-arranged for conformity with the locking portions. Alternatively, or additionally, in another example, there may be only a single locking portion comprising one or the other of the first locking portion 161 or the second locking portion 163, and only a single slot 141 or groove 143, respectively. Alternatively, or additionally, in another example, there may be multiple locking portions comprising only one or the other type of the first locking portion 161 or the second locking portion 163, and only the respective type of the slot 141 or groove 143, respectively. Alternatively, or additionally, in another example, there may be multiple locking portions comprising at least one of each type of the first locking portion 161 or the second locking portion 163, and at least one respective type of the slot 141 or groove 143, respectively.

As shown in Figs 4A-4C, in this example the pivot portion 164 of the locking member 160 comprises two pivot axles 164a arranged to be received in a snap-fit manner in pivot axle recesses 124a of the first structural member 120. Additionally, in this example the pivot portion 164 of the locking member 160 comprises a curved outer surface 164b configured for sliding contact with the curved surface 124b of the pivot seat 124 of the first structural member 120. In this manner, the locking member 160 can be mounted to the first structural member 120 to restrict relative movement to relative rotation only about the axis of the pivot portion 164. Application of a force to the lever 172 of the locking member 160 in a direction having a component orthogonal to the axis of the pivot portion 164 will result in an urging moment, i.e. an urge for the locking member 160 to rotate about the pivot portion 164.

As can be seen from Figs. IB and 1C, in order to assemble the components of the coupling system 100, the following steps are carried out.

First, the second structural member 140 is brought into engagement with the first structural member 120 by causing the respective projections of the structural members 120, 140 to be received in the corresponding recesses thereof. This is achieved by bringing the second structural member 140 towards the first side A of the first structural member 120.

Second, the locking member 160 is brought towards the second side B of the first structural member 120, i.e. the opposite side of the first structural member 120 from the first side A. Since the second structural member 140 and the locking member 160 are brought towards the first structural member 120 from opposite directions, a sandwich or clamping tightening effect can be achieved as will be described in the following steps.

Third, the locking member 160 is angled such that the pivot portion 164 thereof is brought into contact with the pivot seat 124 of the first structural member 120, and such that the arm 170 of the locking member 160 passes via the through-bore 130 of the first structural member 120. Since the arm 170 of the locking member 160 passes via the through-bore 130 of the first structural member 120, the first and second locking portions 161, 163 can enter the respective open ends-portions 141b, 143b of the respective arcuate slot 141 and arcuate groove 143. In such an angled configuration, the lever 172 of the locking member 160 projects away from the first structural member 120 in a direction along the lever 172 away from the pivot portion 164. This is an unlocked position, or open position, of the locking member 160 and the lever 172.

In this example, the pivot axles 164a which protrude from either side of the pivot portion 164 in a direction parallel to the axis of rotation of the pivot portion 164 are mounted by a snap-fit connection into the pivot axle recesses 124a of the first structural member 120, and the curved outer surface 164b of the pivot portion 164 is thus brought into contact with the curved surface 124b of the pivot seat 124 of the first structural member 120. Such a snap-fit mounting can be a semi-permanent arrangement, such that the snap-fit mounting of the locking member 160 does not need to be reversed should the lever 172 need to be moved to the unlocked position in order to allow separation of the first and second structural members 120, 140. Nevertheless, with application of force from appropriate angles to the locking member 160 and/or the first structural member, it may be possible to disassemble the snap-fit mounting arrangement.

The second and third steps above can be carried out in the opposite order, with the pivot portion 164 of the locking member 160 being brought into contact with the pivot seat 124 of the first structural member 120, and the lever 172 of the locking member 160 being arranged in the unlocked position described above, prior to bringing the first and second structural members 120, 140 into contact with each other.

In some cases, when the locking member 160 is snap-fit mounted to the first structural member 120, there is no need when assembling the coupling system 100 to join the locking member 160 to the first structural member 120. In any case, the lever 172 of the locking member 160 needs to be arranged in the unlocked position described above, prior to coupling the first and second structural members 120, 140 together. Fourth, a force is applied to the lever 172, to urge the lever 172 of the locking member 160 in a rotary manner, i.e. to apply a torque or a moment, about the pivot portion 164 towards the first structural member 120. As the lever 172 is rotated, the arm 170 necessarily also rotates about the pivot portion 164, causing the first and second locking portions 161, 163 to move in substantially concentric arcuate paths along the respective arcuate slot 141 and groove 143.

As can be seen from Figs. 3A and 1C, as the first and second locking portions 161, 163 are brought towards the end-portions 141a, 143a of the arcuate slot 141 and groove 143 respectively, first and second locking portions 161, 163 become engaged within the arcuate slot 141 and groove 143, thereby reducing and/or preventing relative motion of the locking member 160 and the second structural member 140 in a direction between the first and second sides A, B of the first structural member, i.e. in a direction opposite to the direction in which the locking member 160 and the second structural member 140 were brought towards the first structural member 120.

Since the locking member 160 and the second structural member 140 are located on opposite sides of the first structural member 120, and since the arm 170 of the locking member 160 passes through the through-bore 130 in the first structural member 120 and engages in a secure manner with the second structural member 140 as described above, the first structural member 120 is effectively sandwiched securely between the locking member 160 and the second structural member 140. Accordingly, a secure engagement and a secure coupling can be achieved when the components are assembled in an engaged manner.

Additionally, as can be seen in the example of Fig. 3A, the end-portion 141a of the arcuate slot 141 can be curved slightly downwards, i.e. in a direction towards the locking member 160 when the coupling system 100 is assembled, such that as the first locking portion 161 engages with the end-portion 141a of the arcuate slot 141, the second structural member 140 is pulled or urged towards the locking member 160, thereby causing a tighter, more secure sandwiching engagement of the first structural member 120 between the second structural member 140 and the locking member 160.

The lever 172 can be rotated until an outer surface thereof lies flush with or recessed within an outer surface of the first structural member 120, since the lever 172 is at least partially housed within the lever receiving recess 132 of the first structural member 120. In this manner, accidental unlocking of the coupling system 100 can be prevented since it is not easy to accidentally operate, i.e. rotate, the lever 172 to the unlocked position from the locked position. Furthermore, a smooth, continuous surface can be achieved which can be aesthetically beneficial.

In this particular example, as the lever 172 reaches the fully closed or locked position in which the lever 172 has been rotated fully to move the arm 170 and locking portions 161, 163 along the full extent of the arc of translation, a clicking sound is heard, and/or a snap-fit occurs between the locking member 160 and one or more of the first structural member 120 and the second structural member 140, to lock the lever 172 semi permanently in the locked position. Such a semi-permanent snap-fit can be reversed by application of sufficient force to the lever 172 in a direction of rotation of the lever 172 towards the unlocked position.

The lever receiving recess 132 in the first structural member 120 in which the lever 172 can be housed can be larger than the size of the lever so as to allow a significant clearance fit. Such a significant spacing around the lever 172 within the lever receiving recess 132 can allow an operator, such as a human operator, to use their fingers or another tool to pry open the lever 172, or rotate the lever 172 to an unlocked position. Such an arrangement allows easy disassembly and reassembly of the coupling system 100.

Figs. 5A and 5B show an exemplary furniture item, namely a shelving unit 200, comprising the coupling system 100 of Figs. 1A-1C. As shown, the shelving unit 200 comprises a plurality of upright members 220 having lateral shelf-supporting members 240 connected therebetween, configured for supporting shelves 260. In order to couple the upright members 220 to the lateral shelf-supporting members 240, there are provided lateral projections 230 projecting radially from the upright members 220. In this exemplary arrangement, the lateral projections 230 each comprise the first structural member 120 as described above. Each of the lateral projections 230 is configured to connect with a portion of one of the lateral shelf- supporting members 240.

In this arrangement, the lateral shelf-supporting members 240 take the form of a central member 242 having forked ends 244, so that each lateral shelf-supporting members 240 is connected to four surrounding upright members 220. However other shapes of lateral shelf-supporting members 240 are envisaged, such as single beams spanning two upright members 220, an X-shaped structure, i.e. having two intersecting beams connected to four surrounding upright members 220, or an integral shelf having shelf-supporting member projecting therefrom. Each portion of the lateral shelf-supporting members 240 which is arranged to connect with one of the lateral projections 230 comprises the second structural member

140 as described above. Finally, locking members 160 as described above are provided (not visible in the exemplary furniture item of Figs. 5A and 5B) to provide a coupling system at each joint.

Since assembly is achieved by lowering the lateral shelf-supporting members 240 to engage with the lateral projections 230, the lateral shelf-supporting members 240 rest on and are supported by the lateral projections 230.

The furniture item may comprise any configuration as would be understood by the skilled person in the art, and should not be understood to be limited to the particular exemplary configuration shown in Figs. 5A and 5B.

Figs. 6A and 6B shows the furniture unit of Figs. 5A and 5B in a state of disassembly. As shown, the locking members 160 have been unlocked by rotation of their respective levers 172 about their pivot portions 164 from a locked position in which the levers 172 are flush with or recessed within the lever receiving recesses 132 of the first structural members 120 to an unlocked or open position in which the levers 172 project away from the first structural members 120 in a direction away from the pivot portions 164. Such rotation causes the arms of the locking members 160 to rotate and thereby translate the locking portions 161, 163 along their respective arcuate slot 141 and groove 143 until the locking portions 161, 163 are disengaged from their respective arcuate slot

141 and groove 143 via the respective open-end portions 141b, 143b.

Once disengagement has been achieved, the lateral shelf-supporting members 240 comprising the second structural members 140 can simply be lifted away from the first structural members 120. In this manner, the furniture unit can be easily disassembled, and the steps above can be carried out in reverse to achieve reassembly. In this example, during reassembly, as the levers 172 of the locking members 160 are brought to the locked position, a "click sound" is heard, and/or a snap-fit occurs between the locking member 160 and one or more of the first structural member 120 and the second structural member 140, to lock the lever 172 semi-permanently in the locked position as described above.

Thus, the coupling system 100 allows easy reconfiguration of the furniture unit, which is particularly useful for modular configurations such as that shown in Figs. 5A- 6B. As can be seen, in this example, as the pivot portions 164 of the locking members 160 are snap-fit mounted to the first structural members 120, there is no need to remove the locking members 160 from the first structural members 120 in order to disassemble and/or reconfigure the furniture item. Instead the locking members 160 only have to be rotated from the locked position to the unlocked position, in order to allow coupling of the first and second structural members 120, 140.