GB2286337A - Improved means of collapsing and erecting structures - Google Patents

Abstract

A collapsible structure, eg for a bed or merchandise rack, comprising at least three side members 51 - 54 so connected to one another that the structure can be converted between a "collapsed" generally flat state and an "erected" configuration in which the side members form at least three sides of a three-dimensional structure is characterised in that at least one of the connections comprises a stud (59, 60 - Fig 6A) and channel 56 arrangement, two studs being associated with two opposing edges of a first side member, one stud being fixed at or near each opposing edge, and two channels associated with opposing edges of a second side member, the studs being a slidable fit within the channels, the studs and channels being so adapted that the members can pivot and slide relative to one another as they move between the collapsed and erected configurations of the structure. The Figure shows the half-collapsed position and, in outline, the erected position. <IMAGE>

Description

IMPROVED MEANS OF COLLAPSING AND ERECTING STRUCTURES Field of the Invention The present invention relates to an improved construction for structures that can be easily collapsed and erected.

Background to the Invention There is a need for many forms of portable structures which can be easily erected and collapsed at will, yet which once erected are both stable and robust. In the present day this need exists in a very wide variety of technical fields, for example portable buildings, storage units, furniture, bedding, trolleys and display stands to name but a few. This list is not intended to be exhaustive or limiting but is purely to illustrate the wide-ranging applications for such structures.

One essential requirement is that these structures can collapse into a "flatpack" configuration for ease of transport and storage when not in use.

Elements and methods suitable for constructing collapsible structures have been known for some time, for instance as described in GB 2 055 290B and GB 2 179 698B and typically as illustrated in Figures 1 and 2 herein which illustrate the prior art. However, these known methods suffer from some major drawbacks: (a) the side of the structure can flex during assembly and disengage from the channel-section head 12 of the swivel bracket 10; (b) when the swivel brackets are made of steel or other metal, in order to impart the necessary strength, then they tend to scratch and bind on the side elements fitted within them; (c) the swivel brackets are exposed at all times, whether the structure is collapsed or erected, and are both unsightly and susceptible to accidental damage.

It is the object of the current invention to overcome the disadvantages inherent with previous methods and in addition to provide structures with a positive locking arrangement such that they can be locked in an erected configuration as well as in intermediate positions to assist with the erection and collapsing process.

Summarv of the Invention According to a first aspect of the present invention, in its broadest sense, there is provided a collapsible structure comprising at least three side members so connected to one another that the structure can be converted between a so-called "collapsed" configuration in which the structure is in a generally flat state and a so-called "erected" configuration in which the side members form at least three sides of a three-dimensional structure characterised in that at least one of the necessary connections comprises a stud and channel arrangement, two studs being associated with two opposing edges on a first side member, one stud being fixed at or near each opposing edge, and two channels associated with opposing edges of a second side member, the studs being a slidable fit within the channels, the studs and channels being so adapted that the members can pivot and slide relative to one another as they move between the collapsed and erected configurations of the structure.

This arrangement ensures that the operative mechanism is also concealed and is no longer susceptible to accidental damage.

Preferably one or more sides are of framework construction such that one side can nest within the framework of another.

Preferably the stud is a headed stud and the channel is undercut, the stud and channel being adapted such that once the head of the stud is engaged in the channel it is retained therein.

This arrangement ensures that even if the structure flexes during assembly the various sides cannot disengage.

In a particularly preferred embodiment the stud is rotatably mounted such that the orientation of the stud with respect to the side member to which it is attached varies as the structure moves between the collapsed and erected configurations.

Preferably all opposing edges of a channel-containing side member incorporate channels, the channel thus being formed substantially continuously around the edge of that particular side member.

Preferably one or more locking means are provided to retain the structure in a particular configuration.

Preferably the locking means comprises pre-determined stop positions in the channel, the stop positions being adapted to engage with the stud to prevent further sideways movement of the stud with respect to the channel.

This positive locking arrangement means that the assembly can be locked in an erected configuration as well as in intermediate positions to assist with the erection and collapsing process.

Preferably the locking means is a shoot bolt.

In a further preferred embodiment the locking means comprises a peg and notch assembly wherein a peg is provided on one side member and a notch is provided in an adjacent side member, the peg and notch being adapted to engage one with another.

There is further provided a stud for use in a collapsible structure as described above, said stud comprising a stud body and a head, the head being connected to the body by a neck, the stud head being adapted to engage in or be embraced by a channel, characterised in that the stud head extends along the channel by an appreciable amount in relation to the width of the stud neck.

Preferably the head is axially offset from the stud body.

Brief Description of the Drawings Preferred embodiments of the present invention will now be more particularly described by way of example, with reference to the accompanying drawings, wherein: Figure 1 shows a view of a collapsible structure in its assembled state as described in GB 2055 290B; Figure 2 shows a swivel bracket in front elevation as described in GB 2 179 698B; Figure 3 is a diagrammatic view of a collapsible structure according to the first aspect of the present invention in a partially collapsed or partially assembled state; Figure 4 is a view of a structure in its assembled state; Figure 5 shows schematic sections to various components of the structure illustrated in Figures 3 and 4; Figure 6 shows diagrammatically components of a tee-pinion and typical channel sections; Figure 7 shows a complete tee-pinion assembly;; Figure 8 shows a diagrammatic perspective view of two collapsible structures according to the first embodiment assembled one within another; Figure 9 shows a perspective view of the end of a bed base with a pivotable stud; Figure 10 shows a plan view of one corner of the bed base as illustrated in Figure 9 with the stud engaged in a channel; Figure 11 shows various elevations of a stud; Figure 12 shows three end elevations of one part of a bunk bed being converted from an erected configuration (Fig 12A) to a collapsed configuration (Fig 12C); Figure 13 shows an end elevation of a similar bed in a partially collapsed configuration; Figure 14 illustrates a typical bunk bed that can be constructed using the present invention; Figures 15 to 18 illustrate various details of the bed shown in Figure 14.

Description of the Preferred Embodiment A first embodiment of a collapsible structure according to the present invention is generally described in Figure 3 to 7. Figure 3 shows such a structure in a partially collapsed state, the structure comprising four sides of a framework-type construction 51-54. It will be appreciated that sides 52 and 53 are so sized and proportioned that they can fit within side 51 and each of sides 52 and 53 can pivot about one end in order to move between a collapsed configuration in which they are indeed contained within side 51 and a fully-erected configuration in which, in this example, they are perpendicular to side 51. The ends of the sides 52 and 53 furthest from the pivots co-operatively engage with side 54 by means of a stud or tee-pinion and channel arrangement.Thus, sides 52 and 53 are literally constrained so that they can only move along the channel 56 and cannot, therefore, accidentally disengage from side 54. It will be appreciated that there is a channel similar to 56 in the opposite face of side 54 which cannot be seen in Figure 3.

In this description the terms pin,stud and tee-pinion have a generic meaning and are used interchangeably.

The channel 56 has an undercut shape and in this example is formed either by making an elongate slot along the length of a hollow frame member or by forming an undercut channel in an otherwise solid side or frame member. In either case, this arrangement provides for the stud to positively engage with and be retained in the channel 56.

The shape and construction of the studs is generally apparent from Figures 5 and 6. Specifically, the stud comprises a pin 59 having a head 60. The pin is fastened by conventional means at one end to the edge of one of the structure's sides (51-54). The head is designed to fit within and co-operatively engage with a channel 56 which is undercut or otherwise so designed to retain the head 60 and prevent its release from the channel except optionally at pre-determined points 57.

In addition to the head 60, the pin can incorporate a collar 61 wherein the portion of the pin 66 intermediate between the head 60 and the collar 61 has substantially the same diameter as the elongate portion of the pin itself.

The pin or stud can be made from any suitable material such as metal, plastic or other composite material or even wood, provided it has the necessary strength and hard wearing properties. It can be of one piece construction but this need not be the case.

In order to be self-locking at pre-determined points, the pin can be springloaded as shown in Figure 7, such that it is biased towards the channel. In practice, the head end of the pin is biased towards the back of the channel. When collapsing or erecting the structure, the pin moves along the channel 56 until it encounters an enlargement or hole 57 whereupon the collar 61 engages with the hole 57 and is retained in this position by a biasing spring 62. A lug 64 prevents further movement of the pin beyond a certain point and also retains the spring 62.

The stud assembly can be released by compressing the spring 62 away from the collar 61, by means of the lug 64, A cover 63 which fits in snap-fit engagement with the lug 64 can assist in this operation and can also be used to conceal the stud mechanism from view and from accidental damage.

In an alternative arrangement, the holes 57 can extend into the back of the channel so that the head of the pin 60 engages with the channel member instead of or as well as the collar 61.

Furthermore, when a frame structure has been unfolded and the tee-pinion has located automatically at both ends, further frames can be added - either a single or a connected frame - to the inside of the first frame structure, without disconnection. This gives the original structure a completely different purposes, from a racking system to a merchandising stand. Such an arrangement is illustrated in Figure 8.

It will be appreciated that one of the essential elements of this invention is that the sides of the structure are positively held in co-operative engagement one with another. This undercut channel and headed-stud arrangement is just one example of how this engagement can be achieved.

The versatility of this invention can be illustrated with respect to a second embodiment shown in Figures 9 to 12. Figure 9 shows one corner of a base intended in this case for a bunk bed. A generally rectangular frame 70 incorporates a slatted base 71 intended to take a mattress. Studs 72 are attached to the base at or near each corner. In this embodiment the studs 72 are elongate but retain a distinct head portion 73 which is adapted to engage within and travel along a channel 74. However, there are several important new features in this embodiment. Firstly, the stud can rotate with respect to the base so that the base can take up any desired position with respect to the side members. The effect of this is that a very sturdy stud can be used which is significantly stronger than a headed pin.This advantage derives from the fact that the stud no longer has to rotate within the channel but rather the whole stud assembly rotates with respect to the side member to which it is attached.

A second important feature is that the channel member 75 is in the form of a separate extrusion which is set into the side member 76. This brings with it a number of advantages. Firstly a wide variety of materials can be used to construct the various components. It is no longer necessary for the side members to be made of a material strong enough to act as an undercut channel in its own right. Decorative materials can be used and a decorative as well as functional channel can simply be attached to one face of the side member. Aluminium or plastic channels can be used, the materials being chosen to minimise wear, maximise strength and provide the smoothest operation. The channel can also be mounted proud of or away from the face of the side member. This can simplify construction considerably.

In the case illustrated in Figure 10 the channel member is secured in a wide undercut groove in the face of the side member. But this is only one possible arrangement. The stud could be bent as shown in Figure 11, in which case the channel can be located entirely in the side member. The stud 80 in Figure 11 comprises a base 81, bent bar 84 and elongate pin 85. The base 81 is adapted to be secured in a hole or recess in a frame or similar item by means of bolt 82 and washer 83, while still being able to pivot within the hole. The pin 85 may be an integral part of bar 84 or may be joined to it during manufacture.

In summary, this embodiment is intended to encompass any mechanical equivalents of the mechanisms described above.

Figure 12 shows how this arrangement works in practice. Two sides 90, 91 of a bed are connected by a base 92, the connections being by means of the arrangements shown in Figures 9 and 10. The thick dark lines on the sides of 90, 91 represent the channel members 75. In order to collapse such a bed any head-board or bed-end 93 is first slid out of position in the direction of arrow D. The bed can then be collapsed by moving the components in the direction of arrows E, F and G.

In this particular example the bed base 92 rests on brackets 94 incorporated into the side members. The pivotal-type stud arrangement enables the sides to be tilted to enable the bed base to pass by these brackets 94 during erection and when being flat packed. A peg and notch mechanism works equally well and has the advantage that the peg is captive in the notch rather than just resting on a bracket.

The arrangement shown in Figure 13 uses the same principle but incorporates the type of stud shown in Figure 11 where the stud head is axially displaced from the stud body. This enables the channel to be formed in the face of the side member.

It will be appreciated that the terms "pin" and "stud" in this specification have a broad meaning. They are intended to cover any protrusion or assembly of parts capable of slidable engagement with a channel, groove or other surface indentation.

Figures 14 to 18 demonstrate the type of complex collapsible structure that can be developed using the present invention. These figures are intended for illustrative purposes only and are not meant to limit the invention for use in beds alone.

A collapsible structure of this type can be made more rigid by adding end or side panels which can simply be slid down the existing channels. By extending the channels along each edge of the side members then this operation becomes particularly simple.

Various locking mechanisms are envisaged or indeed the components can simply be bolted together after erection as shown in Figures 15 and 16.

Summarv The advantages of this method over and above the prior art are as follows: (i) the sides cannot easily disengage even if there is significant flexing of the structure frame members; (ii) the studs, which in one embodiment are effectively spring-loaded, automatically engage as they pass the holes 57. This prevents the structure collapsing in an uncontrolled manner and, as such, is a valuable safety feature; (iii) the folding mechanism is not visible when the structure is viewed in side elevation and thus provides an opportunity to streamline/improve the appearance of the assembled product; (iv) the folding mechanism is automatically protected from accidental damage; (v) additional bars or frame members can be added after erection and without disconnection of the system. Thus, it is now possible to: * increase rigidity * change the function of the structure e.g from a rack to a merchandising stand * stack the framework structures one on top of each other.

(vi) because the folding mechanism may be positioned out of sight, it is possible to increase its size and strength without affecting the visual appearance of the finished article.

Claims (13)

CLAIMS:

1. A collapsible structure comprising at least three side members so connected to one another that the structure can be converted between a socalled "collapsed" configuration in which the structure is in a generally flat state and a so-called "erected" configuration in which the side members form at least three sides of a three-dimensional structure characterised in that at least one of the necessary connections comprises a stud and channel arrangement, two studs being associated with two opposing edges of a first side member, one stud being fixed at or near each opposing edge, and two channels associated with opposing edges of a second side member, the studs being a slidable fit within the channels, the studs and channels being so adapted that the members can pivot and slide relative to one another as they move between the collapsed and erected configurations of the structure.

2. A collapsible structure as claimed in Claim 1 characterised in that one or more side members are of framework construction such that one side can nest within the framework of another.

3. A collapsible structure as claimed in Claim 1 or Claim 2 characterised in that the stud is a headed stud and the channel is undercut, the stud and channel being adapted such that once the head of the stud is engaged in the channel it is retained therein.

4. A collapsible structure as claimed in any preceding Claim in which the stud is rotatably mounted such that the orientation of the stud with respect to the side members to which it is attached varies as the structure moves between the collapsed and erected configurations.

5. A collapsible structured as claimed in any preceding Claim characterised in that all opposing edges of a channel-containing side member incorporate channels, the channel thus being formed substantially continuously around the edge of that particular side member.

6. A collapsible structure as claimed in any preceding Claim characterised in that one or more locking means are provided to retain the structure in a particular configuration.

7. A collapsible structure as claimed in Claim 6 characterised in that the locking means comprises pre-determined stop positions in the channel, the stop positions being adapted to engage with the stud to prevent further sideways movement of the stud with respect to the channel.

8. A collapsible structure as claimed in Claim 6 wherein the locking means is a shoot bolt.

9. A collapsible structure as claimed in Claim 6 wherein the locking means comprises a peg and a notch assembly wherein a peg is provided on one side member and a notch is provided in an adjacent side member, the peg and notch being adapted to engage one with another.

10. A collapsible structure substantially as herein described with reference to and as illustrated in any of Figures 3-18.

11. A stud for use in a collapsible structure as claimed in any preceding Claim, said stud comprising a stud body and a head, the head being connected to the body by a neck, the stud head being adapted to engage in or be embraced by a channel, characterised in that the stud head extends along the channel by an appreciable amount in relation to the width of the stud neck.

12. A stud according to Claim 11 characterised in that the head is axially offset from the stud body.

13. A stud for use in a collapsible structure substantially as herein described and as illustrated in any combination of Figures 9-18.