Background Art Collapsible and erectable box structures are known as are self erecting structures. However, there is a desire to produce a box structure which can be packed flat for storage, and which will self-erect to a usable configuration when released from its flat-packed configuration, which may find use as a play device and/or an enclosure for pet animals for example cats, as a play device for children incorporating the use of dolls or the like, or for other purposes, including horticultural purposes such as a cloche or propagator.

Disclosure of the Invention In accordance with the present invention there is provided a self- erecting box structure which, in an erect condition, comprises first, second, third and fourth walls, said first and third walls being spaced apart by said second and fourth walls, first, second, third, and fourth hinge connections interconnecting respectively the adjacent edges of the first and second walls, the second and third walls, the third and fourth walls, and the fourth and first walls respectively, said first, second, third and fourth hinge connections having axes of hinging movement generally coincident with the adjacent longitudinal edges of their respective walls, said second and fourth walls each being defined by first and second portions interconnected by respective fifth and sixth hinge connections, and said structure being capable of being collapsed by folding along each of said first to said sixth hinge connections in such a manner that said first and third walls are moved towards one another and said second and fourth walls are folded along said fifth and sixth hinge connections respectively, said structure further including resilient means stressed by collapsing movement of the box structure from an erect condition to a collapsed condition so that upon release, in the collapsed condition, said resilient means urges the walls of the box structure to move relative to one another about their hinge connections, the first and third walls being moved away from one another and said second and fourth walls being moved towards a position in which said first, second and fifth hinge connections are generally co-planar and said third, fourth and sixth hinge connections are generally co-planar, and, abutment means against which said second and fourth walls abut in the erect condition of the box structure.

Desirably in the erect condition of the structure said first, second and fifth hinge connections are generally co-planar and said third, fourth and sixth hinge connections are generally co-planar.

Alternatively, said second wall and said abutment means are so configured that in the erect condition of said structure said second wall is arrested in its movement under the action of said resilient means, at a position in which the fifth hinge connection is displaced from a plane containing the first and second hinge connections by a predetermined distance.

Conveniently in addition said fourth wall, when erecting the structure, is arrested in its movement under the action of said resilient means, at a position in which the sixth hinge connection is displaced from a plane containing the third and fourth hinge connections by a predetermined distance.

Preferably said box structure includes a transverse wall between said first, second, third and fourth walls and connected along opposite edges to said first and third walls respectively by respective seventh and eighth parallel hinge connections, said transverse wall being defined by first and second portions interconnected by a ninth hinge connection, said fifth, sixth and ninth hinge connections being generally coplanar and between planes containing said first, fourth and seventh hinge connections and said second, third and eighth hinge connections respectively.

Preferably said resilient means acts between said second and fourth walls to pull the seventh and eighth hinge connections of said walls towards one another to erect the box structure.

Preferably said resilient means comprises a resiliently extensible tether extending across the interior of the structure and interconnecting said second and fourth walls.

Preferably said transverse wall defines, at least in part, said abutment means.

Desirably there is provided a second transverse wall parallel to said first transverse wall and similarly connected to the first and third walls by parallel tenth and eleventh hinge connectors, said second transverse wall also being defined by first and second portions interconnected by a twelfth hinge connector co-planar with said seventh, eighth and ninth hinge connectors.

Preferably said first and second transverse walls are at opposite axial ends respectively of the box structure and define end walls of the box structure, at least one of the walls of the box structure having an aperture therein affording access to the interior of the structure.

Preferably said first and second transverse walls are a lower end wall and a an upper end wall respectively in the normal usage of the structure, and said upper end wall, in the erect configuration of the structure, does not achieve a planar configuration and defines a pitched roof of the structure.

Desirably the box structure includes a third transverse wall disposed intermediate the first and second transverse walls.

Preferably said tether extends, in the erect configuration of the box structure, closely adjacent the hinge line between the first and second portions of a transverse wall, and the tether carries a planar door component for closing, or partially obstructing, an aperture in the transverse wall.

Desirably the box structure includes a plurality of apertures.

Conveniently the box structure is printed, externally, with one or more game boards.

Preferably, the box structure is apertured to receive, after erection, one or more additional components as a sliding fit.

Desirably said first or said third wall is apertured to reveal the interior of the erected structure and has hinged thereto one or more closure panels which, in the erected configuration of the structure can be moved to expose or obscure the interior of the structure.

Brief description of the Drawings The invention will now be described with reference to the accompanying drawings wherein:- Figures 1,2 and 3 illustrate the erect, partially collapsed and fully collapsed condition of a box structure in accordance with a first example of the present invention, Figure 4 illustrates the components of the box structure of Figures 1 and 3 in plan form, as cut from sheet material, Figure 5 is a diagrammatic representation of a variant of the box structure of Figures 1,2 and 3, Figure 6 is a view similar to Figure 5 of a modification thereof, Figure 7 is a view similar to Figure 5 of a box structure in accordance with a second example of the present invention, Figure 8 is a view similar to Figure 7 but illustrating the interior arrangement of the box structure, Figures 9 and 10 are views similar to Figures 7 and 8 of the box structure inverted, Figure 11 is a plan view of the box structure of Figures 7 to 10 collapsed, Figure 12 is a view similar to Figure 4 of the box structure of Figure 7, Figures 13,14 and 15 are views similar to Figure 5 respectively of third, fourth and fifth embodiments of the present invention, Figures 16,17 and 18 are views similar to Figures 7,8 and 12 but of the fourth embodiment, Figures 19,20 and 21 are views similar to Figures 16,17 and 18 but of the fifth embodiment, Figures 22 to 25 illustrate a sixth embodiment and, Figures 26 to 29 illustrate a seventh embodiment.

Preferred Modes of Performing the Invention Referring first to Figures 1 to 3 of the drawings there is shown a box structure which is formed from corrugated cardboard, and which comprises first, second, third and fourth generally planar, elongate, rectangular walls 11,12, 13, 14. In the preferred embodiments the walls 11-14 are integral with one another having been formed from a single sheet of corrugated cardboard material scored along the plurality of parallel lines to define fold lines, as will be described hereinafter in more detail with reference to Figure 4.

The wall 11 is connected to the wall 12 along their adjacent longitudinal edges by means of a first hinge connection 15. The hinge connection 15 is, in the present embodiment, integral with the walls 11 and 12, being defined by a fold line scored into the material from which the walls are made. It is to be understood however that in an alternative method of manufacture the walls could be separately formed and interconnected by any convenient hinge connection, for example, a length of flexible adhesive tape or the like adherent to both walls to produce the hinge connection. In such an arrangement the tape could be a continuous line of tape along the whole of the edge of the walls in question, or could be a series of discrete lengths of tape spaced apart along the edge. In a still further manufacturing method the walls could be formed from moulded synthetic resin material within integrally formed hinge connections defined by thinner regions of the moulded material.

The wall 12 at its edge opposite the wall 11 is connected to the wall 13 by a hinge connection 16, the wall 13 is connected to the wall 14 by an elongate hinge connection 17 and a similar elongate hinge connection 18 connects the walls 14 and 11. Additionally the box structure includes first, second and third transverse walls 19,21, 22, the walls 19,21 being at opposite ends respectively of the hollow tube defined by the walls 11-14, and the wall 22 being within the tube intermediate the walls 19,21. The walls 19,21, 22 are rectangular and are dimensioned to fit between the walls 11-14 in the erect condition. The wall 19 is connected to the walls 11,13 along hinge lines 23,24 and the walls 21,22 are similarly connected to the walls 11,13 along parallel hinge lines 25,26 and 27,28 respectively.

Each of the walls 12,14, 19,21 and 22 is defined by first and second parallel portions indicated in the drawings by the suffix a and b respectively.

The first and second portions 12a, 12b of the wall 12 are interconnected by an elongate hinge connection 29 parallel to the hinge connections 15 and 16 of the wall 12. Similar elongate hinge connections 31,32, 33 and 34 interconnect the first and second portions of the walls 14,19, 21 and 22 respectively.

Figure 1 shows the box structure in a fully erect condition. The walls 11,12, 13 and 14 are planar, and the walls 19,21 and 22 are substantially planar although as shown in Figure 1, the walls 19,21 and 22 may have a very shallow V-configuration about their hinge connections. 32,33 and 34 respectively. The V-configuration is exaggerated in Figure 1 and in practice it is intended that the walls 19,21 and 22 will appear planar.

Figure 2 illustrates a partially collapsed configuration of the box structure of Figure 1. It can be seen that walls 11 and 13 have been moved towards one another as permitted by folding of the walls 12,14, 19,21 and 22 about their central hinge connections. The walls 12 and 14 are shown folding outwardly such that their hinge connections 29 and 31 are moved away from one another, outwardly from the longitudinal centre line of the box structure. Conveniently the walls 19,21 fold inwardly so that their hinge connections 32 and 33 are moved towards one another and in the example illustrated the wall 22 folds in such a direction that its hinge connection 34 is moved towards the hinge connection 32 of the wall 19.

Figure 3 shows the fully collapsed configuration of the box structure in which the box structure is in effect a substantially planar panel. The walls 11, 13 are very close to one another, being spaced by the double thickness of the folded walls 19, 21, 22 and the walls 12 and 14 are folded outwardly so that their portions a and b are substantially in contact with one another.

A resiliently extensible tether conveniently in the form of a rubber shock-cord 35 is anchored at its opposite ends to the walls 12,14 respectively at, or closely adjacent, their respective hinge connections 29,31. The tether 35 extends across the width of the interior of the box structure in the fully erect condition, and is at or adjacent the midpoint of the length of the box structure, that is to say closely adjacent the wall 22. In the fully erect condition of the box structure there is stress in the tether 35 which thus pulls against the anchor points 36 of the tether to the walls 12,14 pulling the walls 12,14 towards one another. The fully erect position of the box is thus defined by the walls 12,14 being planar, and internally abutting the opposite parallel edges of the wall 22. Conveniently the walls 12,14 similarly abut the opposite parallel edges of the walls 19 and 21. Thus the tension in the tether 35 holds the walls 12,14 against the walls 19,21, 22 holding the box structure in its fully erect configuration. The application of collapsing loading to move the walls 11,13 towards one another displaces the hinge connections 29,31 of the walls 12,14 outwardly thereby elongating the tether 35 and increasing the tension therein. When the box structure reaches its fully collapsed configuration as shown in Figure 3, clip means or other restraining devices are applied to the walls 11,13 to hold the walls 11, 13 closely proximate one another, and thus to hold the box structure in its collapsed configuration. Removal of the clips or other restraining means allows the tether 35 to pull the hinge connections 29 and 31 towards one another thereby erecting the box structure without operator intervention.

Figure 4 illustrates the production of the walls 11,12, 13,14, 19, 21 and 22 from a single sheet of corrugated cardboard or the like. It can be seen that the box structure is formed from basically four components conveniently cut from the same base sheet. The first component consists of the integral walls 11,12, 13 and 14 the material being scored along parallel lines to produce the hinge connections 18,15, 29,16, 17 and 31 as integral fold lines in the material. It will be noted that the fold line which produces the hinge connection 18 is between the wall region 11 and an integral tongue 37 and after folding the blank about the line 18,15, 16 and 17 the tongue 37 is adhesively secured to the free edge of the portion 14a of the wall portion 14 so that in effect the hinge connection 18 interconnects the walls 11 and 14.

It will be understood that if desired the walls 11,12, 13,14 could be separately formed and interconnected by tongues adhesively secured to the adjacent wall.

It can be seen that the walls 19,21 and 22 are cut as separate blanks from the base sheet, and each is scored with the respective central hinge connection 32,33, 34, and each has opposite edge tongues 37 connected to the respective wall portion by the hinge connections 23-28 respectively. In use the tongues 37 are adhesively secured to the walls 11 and 13 to affix the walls 19,21 and 23 in position.

Referring to Figure 5 there is shown a final version of the box structure shown in Figures 1,2, 3 and 4. The box structure of Figure 5 is intended as a play device for a domestic cat or similar domestic pet. The wall 12 of the box has a large aperture 41 through which the cat can enter the erected box structure. The wall 22 which divides the interior of the box structure into first and second compartments has a centrally disposed aperture 32 through which the cat can obtain access from the entry compartment having the aperture 41 into the second compartment. The various walls of the structure can be pierced with other apertures (Figures 4 and 5), of any convenient form so that light can enter the compartment, and an animal therein can see out. Figures 4 and 5 show apertures in the form of arrangements of circular apertures 43 and cat's paw shaped aperture arrangements 43.

As the tether 35 passes closely adjacent the wall 22 it extends across the aperture 43, and a disc-like closure member 45 (Figures 4 and 5), conveniently cut from the blank of the wall 22, can be carried by the tether 35 to obstruct, or partially obstruct the aperture 42, the disc 45 being readily displaceable relative to the wall 22 by flexure or twisting of the tether 35 to permit the cat to pass through the aperture 42. It will be understood that the aperture 42 and/or the member 45 can be shaped other than circular.

The walls 12 and 14 may be provided with aligned apertures 36 (triangular in the drawings) through which a post of corresponding cross- section can be threaded when the box structure is in its erect configuration.

The posts (47 in Figure 5) may protrude its ends from the walls 12,14 and may be coated with an abrasive or other material to act as a scratching post for the cat. Furthermore, the exterior and interior walls of the box structure may be provided with printed decoration, or adhesively secured areas of abrasive or other material to provide interesting textures for the animal.

Figure 4 shows that the post 47 can be formed from the same sheet of material from which the blanks for the walls have been cut. The post can be a rectangular blank scored with three parallel fold lines to produce four wall sections. The blank is then folded so that the two outer edge wall sections overlap and can be adhesively secured to one another thereby providing a post of triangular cross-section. If a fold flat post 47 is desired the adhesive at the wall overlap can be omitted as the post, once folded, will be held in its triangular configuration by its engagement in the triangular apertures 36. It will be recognised that the triangular post is fitted manually after the box structure has been erected. Figure 4 also shows that load spreading components 48 can be cut from the base sheet of material, the components 48 being used to spread the load imposed by the tether 35 on the walls 12,14 at the anchor points 36 of the tether 35.

Figure 6 shows a variant of the box structure shown in Figure 5 It is intended that Figure 6 might be suitable for a kitten whereas the Figure 5 embodiment is more suited to a fully grown cat. Figure 6 illustrates that the opposite walls 12 and 14 may both be provided with apertures 41 and that a litter tray 49 could be separately constructed, and inserted into the erected box structure through an appropriately shaped aperture.

Figure 7 illustrates a box structure of the same general configuration as Figure 5, the dimensions being more cuboidal than those of the structure described above. The structure of Figure 7 could be used as a play device by children, or adults. The internal transverse wall 22 of the box structure of Figure 7 differs from that of the embodiments described above in that it is positioned obliquely. The wall 22 extends between the walls 12 and 14 of the box structure and is adhesively secured by glued tongues 37 to the walls 11 and 13 of the box structure as described above. The wall 22 is divided by a fold line hinge connection 34 into portions 22a, 22b and there are fold line hinge connections 27 and 28 between the portions 22a, 22b and their respective tongues 37 which thus define hinge connections between the portions 22a, 22b and the walls 11,13 respectively. The wall 22 differs from the wall 22 of the box structure illustrated in Figures 1 to 3 in that it is shaped such that in the fully erect condition of the box structure the wall 22 maintains a pronounced V-shape and the wall 22 is affixed within the box structure of the walls 11-14 in an oblique configuration such that the fold line 34 of the wall 22 is, where it abuts the wall 12 also adjacent the wall 2 1, and, where it abuts the wall 14, it is adjacent the. midpoint of the wall 14 but disposed just on the wall 21 side of the midpoint of the wall 14. The fold line 34 of the wall 22 lies in the plane containing the fold lines 29,31, 32,33 of the walls 12,14, 19,21 respectively.

The mode of collapsing and erecting operation of the box structure of Figures 7 to 12 is as described above, with the exception that the walls 19 and 21, in addition to the walls 12,14, fold outwardly as the box structure collapses. Thus in addition to the hinge connection 29 moving away from the hinge connection 31 the hinge connection 32 moves away from the hinge connection 33. During collapsing movement the wall 22 folds flat so that its portions 22a, 22b abut in the fully collapsed configuration and lie between the walls 11,13 of the box structure.

As illustrated in Figures 7 to 12, the wall 21 of the box structure has a circular aperture 41 positioned on the line of the hinge connection 33 and at the end of the wall 21 adjacent the wall 12. As is clear from Figure 8, if the box structure is positioned with the wall 21 uppermost then the wall 22 will define two planar surfaces 22a, 22b inclined downwardly towards the opposite comers of the box structure. Thus a dice or other play component introduced into the box structure through the aperture 41 will fall onto either the surface 22a, or the surface 22_ and will be guided by that surface to slide, under gravity, towards the opposite corners of the box structure. The opposite corners are provided, in the lines of the hinge connections 17, 18 with exit apertures 51 through which the dice is returned to the players.

Similarly the wall 19 is formed with similar dice introduction apertures 50 on opposite sides of the line of the hinge connection interconnecting the portions 19a and 19b of the wall 19 and at the end of the wall 19 adjacent the wall 14. Thus if the box structure is positioned with the wall 19 uppermost as shown in Figures 9 and 10 then the two portions 22a, 22b of the wall 22 define a V-shaped trough inclined downwardly to an aperture 52 on the line of the hinge connection 29 of the wall 12a whereby a dice introduced through either of the apertures 50 is returned to the player by way of the aperture 52 in the wall 12. It will be recognised that the number of apertures 41,51, 50, 52 can be altered as desired.

Figure 12 illustrates that the walls 11,12, 13,14 can, if desired, be formed from two blanks, rather than a single blank. In Figure 12 it can be seen that the walls 13 and 14 are formed from one blank while the walls 11 and 12 are formed from a second blank. A tongue at the free edge of the portion 14b of one blank is, in use, adhesively secured to the wall 11, and a tongue at the free edge of the portion 12b of the other blank is adhesively secured to the wall 13 to produce the box structure. Figure 12 also shows the tongues 37 of the walls 19,21 and 22.

Game boards, including those of games played with dice may be printed on one or more faces of the box structure. The problem often found when playing dice games, particularly with children, is that exuberance tends to cause vigorous throwing of the dice, with subsequent need to retrieve the dice often from considerable distances. Such problems are obviated by the box structure of Figure 7 since the dice are contained by the box structure and are returned to the players through the aperture Figure 13 illustrates a box structure which may be more suitable for use by children with dolls, for example"Action Man"-type dolls. The box structure is shaped to define a castle turret or the like having apertures for windows, and being externally printed accordingly. One end of the box structure may be notched to provide the effect of castellations 53. The box structure of Figure 13 may make use of only a single transverse wall, conveniently in the position of the wall 22 of the Figure 5 embodiment and that wall may have a rectangular aperture obstructed, or partially obstructed by a rectangular flap, in the form of a trapdoor 45 carried by the tether 35.

In addition to apertures for windows one or more walls of the box structure of Figure 13 may have-an aperture for a door, including a hinged closure member 54 integral with the remainder of the wall. It will be understood that the box structure of Figure 13 could, if desired, have one or more additional transverse walls, for example one adjacent the end of the box structure remote from the castellations 53 to define a floor and another just below the level of the castellations to define a flat roof.

Figure 14 shows a variant of Figure 13 in which the castellated end region 53 of the box structure is replaced by a pitched roof structure 55 which folds along the ridge 56 to permit the structure to fold flat. Figures 16, 17 and 18 show the embodiment of Figure 14 in more detail, the roof 55 being a variant of the wall 21 of Figures 1 to 3 which is dimensioned to remain in a V-shape, the ridge line 56 being, in effect, the hinge line 33 of the wall 21 and the wall folding outwardly as the structure is collapsed.

Figures 15,19, 20 and 21 show a variant of Figure 14 used as a toy post box having a posting slot 57 and a post retrieval aperture closed by a hinged panel 59, in the wall 11.

Figures 19,20 and 21 illustrate the embodiment of Figure 15 in more detail. It can be seen that the embodiment of Figure 15 is very similar to the embodiment of Figure 14 with the exception that the roof blank has a conventional tongue 37 at one edge, but an enlarged tongue 61 at its opposite edge. The enlarged tongue 61 terminates in a foldable flap 62 which is not adhesively secured to the interior of the wall 11, but instead is folded to extend through the aperture 57 to form a cowl over the"posting"slot 57 The main part of the tongue 61 and the opposite tongue 37 are however adhesively secured to the inner surfaces of the walls 11 and 13 respectively.

Desirably in all embodiments formed from corrugated cardboard or the like the lines scored on the various corrugated blanks to produce the fold lines are arranged to extend at right angles to the length of the flutes of the corrugated material.

Figures 18 and 21 show that the blank can be pierced to form apertures defining windows or posting slots and the like. Some of the apertures can have integral flaps joined to the remainder of their wall by a hinge connection so that they form openable doors in the walls. Moreover, a clear PVC sheet may be cut to form window closures to define, in effect, window panes.

The embodiment of Figures 22 to 25 is a dolls house and is a variant of the embodiment of Figures 16 to 18. It can be seen that the embodiment of Figures 22 to 25 has a wider"frontage"than that of Figures 16 to 18, and has a slide-in separately formed chimney stack component 55b inserted through an aperture 55a in the roof 55. Moreover the wall 11 (or the wall 13) is apertured as seen in Figure 25 to reveal the interior of the dolls house and to provide access for a child to rearrange furniture and the like therein.

The apertured wall 11 carries one or more hinged closure panels 1 la, 1 lb which when closed) depict an outer wall of the house and which can be hinged to an open position to access the apertured wall 11.

In the embodiment of Figures 26 to 29 both end walls 12,14 do not hinge sufficiently far in the erect configuration for the walls to be planar. Instead the walls 12,14 remain in a projecting,'V'configuration so that the structure has six boundary walls in the erect configuration. The or each internal wall 22 is shaped to abut the walls 12,14 at the appropriate point during erection to prevent the elastic cord 35 pulling the walls 12,14 to a planar configuration. It will be recognised that if desired one of the walls 12, 14 could be designed in conjunction with design of the wall 22 to be planar in the erect configuration so the structure is pentagonal. Figure 26 illustrates the withdrawal of the collapsed structure from a container C which holds the collapsed structure for storage or carriage. As with the doll's house above, the wall 11 is apertured to provide access to the interior and a closure panel 11 a is hinged to the wall 11. In order to complete the roof of the structure the walls 12,14 carry roof elements 55b which abut the roof elements 55a carried by the walls 11,13. Additional components such as ramps, stairs lift shafts and the like can be attached to the structure after erection.

In order that window boundaries and other edges of the structure shall not present cut material edges to the user the edges can be double thickness being defined by inwardly bent flanges of the material so that each exposed edge is a fold line in the material rather than a cut edge. Walls which have double thickness and window apertures can have acetate or similar sheet material between the wall layers to define window panes.

It is not essential that end walls such as 19 or 21 are flush with the edges of the walls 11-14, and they can, for example, be inset as seen in Figure 27 Although not illustrated in the drawings it is to be recognised that a similar self-erecting box structure could be formed from a transparent or translucent plastics material and could be used as a cloche to protect plants in a garden, or as a propagator enclosure for use in, for example, a greenhouse.

In all of the above embodiments it may be convenient to provide the ends of the shock-cord tether 35 with clips or moulded-on devices to act as load spreaders or handles, and/or to define loops in the shock-cord to act as handles. Moreover where the structure has no internal wall then some form of abutment means will be provided, to define the erect condition of the structure, against which the walls pulled by the tether abut. An elongate tube through which the tether extends could be provided, the opposite axial ends of the tubes being abutted in the erect configuration by the opposite walls to which the tether is anchored.