GB2245251A - Collapsible containers - Google Patents

Abstract

A container assembly, typically of parallelopipedon form has a flat base 1 and two opposed plastics moulded wall members 2, 3 upstanding from the base. Each wall member is pivotally mounted relative to the base by an L-shaped hinge structure 100 coupled between the base and the respective wall member so that the wall members are displaceable into a fold-flat condition over the base with a first wall member overlying the second wall member and said overlying wall members are in substantially parallel relationship with each other and with the base. The two wall members are identical mouldings to permit manufacture in the same moulding tool and the hinge structure loo of the first wall member differs from that on the second wall member to accommodate for the thickness of the second wall member in the fold-flat condition. The hinge structure is formed by L-shaped plastics components 104, 105 which are assembled around a pivot pin 11 on the base and retained thereon by snap engagement of legs of the hinge components in recesses 113, 114 in a bottom socket of the respective wall member. <IMAGE>

Description

TITLE "A container assembly" TECHNICAL FIELD & BACKGROUND ART The present invention relates to a container assembly and is particularly concerned with such an assembly of the fold-flat type and which is predominantly formed by relatively rigid plastics moulded components. Fold-flat containers are known having a substantially flat base with two or more side walls upstanding from the base to provide an open top. A typical known container is of generally parallelopipedon shape. The side walls are pivotally mounted to the base to be foldable successively into overlying relationship with the base and with two or more of the side walls in overlying relationship with each other.With the side walls thus folded to lie in substantially parallel planes with the base, the assembly presents a generally flat pack which is convenient both for storage or transport when the container is not in use.

Releasable snap-engaging clips or other locking devices are usually provided on the side walls to retain them in their upstanding condition when the container is required for use.

In a conventional form of fold-flat container having the base and side walls formed as plastics mouldings, the side walls which are foldable into overlying relationship with each other and with the base are of relatively different heights in their upstanding condition and are pivotally mounted on upstanding flanges of the base. The upstanding flanges are of relatively different heights so that the respective flanges and side walls which are pivotted thereto present an overall uniform height to the container assembly when the side walls are in an upstanding condition.When the side walls are pivotted to their fold-flat condition, the relative difference in height between the upstanding flanges of the base accommodates for the thickness of a side wall or side walls which underlies the side wall which is pivotted to a particular upstanding flange so that the parallel relationship between the folded side walls can be achieved. While such a known container assembly is convenient in its fold-flat condition for storage and transport, it does not lend itself to commercially viable manufacture. Because of the different heights required of the side walls which are to overlie each other in the fold-flat condition, such side walls conventionally require moulding in different plastics moulding tools (typically three or four different moulding tools may be required to mould the four upstanding side walls of a parallelopipedon shaped container).

In a further known form of fold-flat container the side walls have a cranked or generally L-shaped configuration in section of which the side wall generally forms a long leg of the configuration and a short leg of the configuration is pivotally mounted to the base. When the wall members are displaced into the fold-flat condition, the length of the aforementioned short leg on a particular side wall accommodates for the thickness on the base of another side wall which it overlies. An example of this latter known type container is disclosed in British Specification A1,308,456.

In the manufacture of plastics fold-flat containers it is recognised that the provision of appropriate moulding tools is expensive, particularly for forming the side walls of relatively large sized containers, and the cost of this tooling is an important consideration in the commercial viability for such containers. It is an object of the present invention to provide a container assembly of the fold-flat type which is predominantly formed by plastics moulded components and by which the cost of the tooling for the moulding of the plastics components, especially side walls of the container, may be alleviated.

STATEMENT OF INVENTION & ADVANTAGES According to the present invention there is provided a container assembly having a substantially flat base and two plastics moulded wall members upstanding from the base, each wall member being pivotally mounted relative to the base by hinge means coupled thereto and to the base so that the wall members are displaceable into a fold-flat condition over the base where a first of the wall members overlies the second wall member and said wall members are in substantially parallel relationship with each other and with the base, and wherein the two wall members are substantially identical mouldings and the hinge means coupled between the first wall member and the base differs from the hinge means coupled between the second wall member and the base so that in the fold flat condition the hinge means of the first wall member accommodates for the thickness of the second wall member.

By the present invention the first and second wall members are substantially identical in the sense that those wall members may be moulded in the same basic moulding tool and thereby the cost of tooling is alleviated. However, it is to be realised that although the two wall members may be moulded. in the same moulding tool they need not necessarily be identical in the sense that the moulding tool may have replaceable inserts (as is well known in plastics moulding practice) so that small differences may be presented between the two wall members, for example one wall member as compared with the other may have a Trade Mark, particulars of load carrying capabilities of the container assembly or other incidental characteristics moulded therein.

The first and second moulded wall members will usually be located along opposed substantially parallel side edges of the base and typically the container assembly will be of parallelopipedon shape having four pivotally mounted side walls an opposed pair of which side walls will be provided by the first and second wall members. The second opposed pair of side walls may also be formed, albeit with different dimensions, and pivotally mounted to the base in a similar manner to the first and second wall members so that all four of the side walls can be displaced from their upstanding condition into a fold-flat condition on the base with the hinge means of the respective side walls accommodating for the thickness of such side wall or side walls which it may overlie.

Preferably each hinge means comprises a substantially L-shaped hinge structure having one leg thereof pivotally mounted to the base and the other leg thereof coupled to the respective wall member. The said one leg of the hinge structure on the first wall member is longer than said one leg of the hinge structure on the second wall member so that the greater length of the one leg on the first wall member accommodates for the thickness of the second wall member in the fold-flat condition of the assembly.

Although differently dimensioned hinge structures are necessary for the two wall members the coupling between those hinge structures and the respective wall members is preferably identical for convenience of assembly. The hinge structures are preferably formed as plastics mouldings and although different moulding tools may be required for the hinge structure of the first wall member as compared with that for the second wall member, the hinge structures will be relatively small in comparison with the wall members so that the cost of the moulding tools for their manufacture may be relatively small in comparison with that for the wall members. For convenience of assembly the hinge structures preferably snap engage with their respective wall members to form a rigid structure therewith. It is also preferred that the hinge structures are pivotally connected to the base by pivot pins.The base will usually be formed as a plastics moulding with appropriately located integral pivot pins, such pins being anchored or integral with the base moulding at each end.

Again for convenience of assembly it is preferred that the hinge structure is formed by two hinge components which are assembled around the pivot pin on the base and retained on the pivot pin by the coupling of the hinge components with the respective wall members.

DRAWINGS One embodiment of a container assembly constructed in accordance with the present invention will now be described, by way of example only, with reference to the accompanying illustrative drawings in which: Figures 1 and 2 show side and end views respectively of the assembly and diagrammatically indicate the manner in which the assembly is adjusted to its fold-flat condition, and Figure 3 is a detailed section of a hinge structure provided between the base and a side wall of the assembly.

DETAILED DESCRIPTION OF DRAWINGS The container assembly of Figures 1 and 2 is shown in diagrammatic form only and when erect has a generally parallelopipedon configuration comprising a substantially oblong rectangular flat base 1 extending upwardly from which are opposed side walls 2 and 3 and opposed end walls 4 and 5 which form an open top to the container. Each of the walls 2 to 5 is formed as a plastics moulded component.

In particular the side walls 2 and 3 are identical to each other and the end walls 4 and 5 are identical to each other so that the four walls can be manufactured in two moulding tools. The four walls are pivotally mounted to the base 1 by hinge structures 100 which are substantially of L-shape in section of which one leg is coupled to a pivot pin 11 on the base and the other leg is rigidly attached to its respective wall. Usually each wall will be pivotally mounted on the base through two or more of the hinge structures 100 which are spaced along the relevant side edge of the base.

The height of each of the end walls 4 and 5 above the base 1 is less than half the length of the base and when the container assembly is not in use its side and end walls can be pivotted relative to the base 1 on the pins 11 into a fold-flat condition, firstly by lowering the end walls 4 and 5 in the directions of arrows A and B respectively as shown in Figure 1 so that the end walls overlie and abut the base 1 in substantially parallel relationship therewith. In Figure 1 the partly folded container assembly is shown in side view with the side wall 3 omitted for convenience of illustration.

Following flat-folding of the end walls 4 and 5, the side wall 2 is pivotted relative to the base about its pins 11 and in the direction of arrow C in Figure 2 so that the side wall 2 overlies and abuts the end walls 4 and 5 in substantially parallel relationship with those walls and with the base. Final flat-folding of the assembly is achieved by pivotting the side wall 3 relative to the base about its pins 11 in the direction of arrow D shown in Figure 2 so. that the side wall 3 overlies and abuts the side wall 2 in substantially parallel relationship therewith.

To permit the assembly to adopt its fold-flat condition, the length of the leg which is connected to the pivot pin on the hinge structure 100 of the side wall 2 is such as to accommodate for the thickness of the coplanar end walls 4 and 5 which the side wall 2 overlies and abuts so that the generally parallel relationship between those walls is possible. Similarly the length of the leg which is connected to the pivot pin on the hinge structure 100 for the side wall 3 is such as to accommodate for the thickness of the end walls 4 and 5 and also for the thickness of the side wall 2 which the side wall 3 overlies and abuts so that the generally parallel relationship is attained.

Although the end walls 4 and 5 are indicated as being pivotally mounted on the base through hinge structures 100 in a similar manner to the side walls, it will be realised that these end walls can be pivotted to the base other than by the use of an L-shaped hinge structure 100 so that the end walls will fold-flat to abut the base; for example the end walls 4 and 5 can be pivotted by pins extending through small upstanding flanges on the base (similarly to a piano hinge) as it may not be necessary for these end walls to pivot in a manner which accommodates for the thickness of an underlying wall.

The general arrangement of each hinge structure 100 is shown in Figure 3 which provides a pivotal coupling between the base 1 and the side wall 2 (or alternatively the side wall 3, 4 or 5). In Figure 3 the side wall is shown in an upstanding condition relative to the base 1 and moulded in the lower portion of the side wall is a socket 101 which opens into the bottom edge 102 of the side wall. The base 1 is formed as a plastics moulding having integral cylindrical pivot pins 11. The axis of each pivot pin extends parallel to the side edge of the base from which the relevant side wall which is to be coupled to that pin extends. The ends of each pin 103 are integral with the plastics material of the base so that each pin is located in a recess 10 of the base.

The hinge structure 100 is formed by two plastics moulded components 104, 105 which are of generally L-shape in section as will be seen from Figure 3. The hinge component 104 has a channel 106 within which is intended to be received an end part 105A of the hinge component 105.

The hinge components 104 and 105 are assembled around the hinge pin 103 with the end part 105A of the component 105 received as a firm fit within the channel 106. Following mating of the parts 106 and 105A, leg parts 107 and 108 of the hinge components are urged into abutment with each other so that the components 104 and 105 capture the pin 11 and are a firm but sliding fit on the cylindrical surface of the pin. Preferably the hinge component 104 is provided with a part cylindrical seating 109 within which the pin 103 is received as a complementary fit and the hinge component 105 is similarly provided with a part cylindrical seating 110 within which the pin is received.

The leg parts 107, 108 of the hinge structure are provided with external flanges 111 and 112 respectively. With the hinge structure 100 assembled on the pivot pin 11 as described, the leg parts 107 and 108 are force fitted into the socket 101 in the side wall through the bottom edge of that side wall so that the flanges 111 and 112 snap engage in recesses or apertures 113 and 114 respectively provided in opposed sides of the socket 101. To facilitate this engagement the side edges of the flanges 111 and 112 are tapered or chamfered to provide appropriate lead-in surfaces as those edges slide over the interior faces of the socket to snap engage with the respective recesses.

Following such snap engagement an internal bottom edge 115 of the side wall may abut the hinge component 104 to maintain a relatively rigid connection between the hinge structure 100 and the side wall through the flanges 111 and 112 being urged by the resilience of the plastics into abutment with the bottom surfaces of the respective recesses as shown in Figure 3.

The upstanding condition of the side wall shown in Figure 3 is determined by abutment of the bottom outer edge 102 of that side wall against the base 1 and also by abutment of the hinge component 105 of the hinge structure against an appropriately profiled seating 115 which is presented by the base 1 in the recess 10.

It will be seen from Figure 3 that the hinge structure 100 assembled from the hinge components is of generally Lshaped section one leg of which is coupled to the pivot pin 11 and the other leg of which is rigidly coupled to the side wall so that the side wall and hinge structure 100 can exhibit unified pivotal movement or rotary displacement about the pin in the directions indicated by the arrows in Figure 3 and from a position in which the side wall upstands substantially perpendicularly from the base 1 to a position in which the side wall overlies the base 1 in a plane substantially parallel therewith (either to abut the base or to be spaced therefrom depending upon the particular side wall under consideration).From the aforegoing description with reference to Figures 1 and 2 it will be apparent that the length of the leg in the hinge structure 100 which is pivotally connected to the pin 11 will be the same for the hinge structures of the side walls 2 and 3 but will differ between those hinge strucures and each of the hinge structures of the side walls 4 and 5 (depending upon what side wall or side walls a particular side wall is intended to overlie so that the hinge structure of the particular side wall can accommodate for the thickness of the underlying side wall or side walls).

With this in mind the dimension X shown in Figure 3 in the length of the leg of the hinge structure which is coupled to the pin 11 and which dimension is taken from the axis of the pin to the leg parts 107 and 108 in the plane of the side wall will vary between the respective side walls (other than for between the side walls 4 and 5). The hinge components 104 and 105 will therefore be moulded accordingly to provide the required leg length X in the three sizes of hinge structure 100 illustrated in Figures 1 and 2 and as shown at XA, XB and XC. Similarly the base 1 will be moulded with the recesses 10 and seatings 115 appropriately sized and positioned to accommodate the size of hinge structure 100 which is to be attached to the pivot pin 11 in the respective recess 10.

Claims (12)

1. A container assembly having a substantially flat base and two plastics moulded wall members upstanding from the base, each wall member being pivotally mounted relative to the base by hinge means coupled thereto and to the base so that the wall members are displaceable into a fold-flat condition over the base where a first of the wall members overlies the second wall member and said wall members are in substantially parallel relationship with each other and with the base, and wherein the two wall members are substantially identical mouldings and the hinge means coupled between the first wall member and the base differs from the hinge means coupled between the second wall member and the base so that in the fold-flat condition the hinge means of the first wall member accommodates for the thickness of the second wall member.

2. An assembly as claimed in claim 1 in which the hinge means comprises a substantially L-shaped hinge structure having one leg thereof pivotally mounted to the base and the other leg thereof coupled to the respective wall member and wherein said one leg of the hinge structure on the first wall member is longer than said one leg of the hinge structure on the second wall member so that the greater length of the one leg on the first wall member accommodates for the thickness of the second wall member in the foldflat condition.

3. An assembly as claimed in claim 3 in which said other leg of the hinge structure is rigidly coupled to the respective wall member.

4. An assembly as claimed in either claim 2 or claim 3 in which said other leg of the hinge structure is coupled to its respective wall member by snap engagement in a socket of that wall member.

5. An assembly as claimed in any one of the preceding claims in which the hinge means is pivotally connected to the base by a pivot pin.

6. An assembly as claimed in claim 5 in which the pivot pin is carried by the base and the hinge means is attached thereto.

7. An assembly as claimed in claim 6 in which the hinge means comprises two hinge components which are assembled around the pivot pin on the base and are retained pivotally connected to the pin by the coupling of said hinge components with the respective wall member.

8. An assembly as claimed in any one of the preceding claims in which the hinge means is formed by moulding in relatively rigid plastics.

9. An assembly as claimed in any one of the preceding claims in which the base is formed as a plastics moulding.

10. An assembly as claimed in any one of the preceding claims in which the base presents seatings which locate the respective wall members in their upstanding condition.

11. An assembly as claimed in claim 10 when appendant to claim 2 in which the seatings accommodate the hinge structures of the respective wall members in their upstanding condition and the seatings differ for the respective hinge structures to accommodate for the greater length of the one leg on the hinge structure of the first wall member as compared with the length of the one leg on the hinge structure of the second wall member.

12. A container assembly substantially as herein described with reference to the accompanying illustrative drawings.