GB2360320A - Foldable shuttering - Google Patents

Abstract

Shuttering comprises at least thee shutter elements each with hinge means at an end for mutual connection end to end in use, the end faces of the elements being cut at angles such that when hinged together, end faces are brought into abutment so that the hinged assembly is rigid and defines a predetermined configuration. The shuttering may be provided with levelling means including a spirit level, and may be used e.g. for casting a foundation slab for a shed or the like.

Description

2360320 Shuttering The present invention relates to shuttering apparatus

and to a method of shuttering, useful for example in the making of bases or similar foundations for temporary buildings such as sheds or summerhouses or house extensions.

The process for making concrete foundations such as bases for sheds usually starts with ground preparation, over an area which is at least the size of the foundation required. Timbers or such like for shuttering are then cut to size and joined together to make a frame. This frame is then fixed to ground pegs to form the shuttering. The shuttering is then usually squared, so that the angles of the corners are at right-angles, and levelled so that the foundation will be flat and horizontal.

This process involves measuring, cutting, fixing, squaring and securely levelling the shuttering. This task can be awkward and time consuming and it requires a variety of tools for the particular separate operations. The purpose of the invention is to overcome or at least mitigate these disadvantages.

Accordingly, the invention provides shuttering apparatus comprising at least three elongate shutter elements each with hinging means at at least one of its ends for mutual connection end to end in use, the end faces of the elements being cut at angles such that, when hinged together end to end in use, the pairs of opposed end faces may all be brought into abutment so that the hinged assembly is rigid and defines a predetermined polygonal shuttering configuration.

The invention enables the provision of pre-formed shuttering which can readily be assembled into a rigid structure on site. This avoids the need for specialist tools and for the carrying out of operations that would otherwise be necessary.

Preferably, there are at least four shutter elements all hinged together such that the shuttering is flexible between a flat, closed configuration, with the shutter 1 elements parallel, and a fully open configuration defining a polygon, at which the pairs of end faces of the shutter elements are ail in mutual abutment. This has the advantage that the shuttering is completely pre- assembied, for example in a flatpack form for easy transport, ready for simply opening out on site to form instant 5 shuttering.

The shutter elements may be of the same or different lengths, and their end faces may be cut at an acute angle or square, for example. The predetermined polygonal shuttering configuration may be regular, for example rectangular or hexagonal, or irregular, to form more intricate shapes as required.

The shuttering apparatus preferably comprises means for bracing two of the shutter elements together to maintain the shuttering at its predetermined shuttering configuration with the end faces in abutment.

The hinging means may take a variety of different forms, for example with centre pins, or else integral structures such as a band of metal or plastics material with an integral hinge.

The invention also provides a method of preparing shuttering using shuttering apparatus as defined above, comprising arranging the shutter elements end to end in a closed loop configuration and flexing the configuration to bring the said pairs of opposed end faces all into abutment and thereby to set the assembly at the predetermined polygonal configuration.

In order that the invention may be better understood, preferred embodiments of the invention will now be described, by way of example only, with reference to the accompany drawings, in which:

Figures 1 a to 1 c illustrate, in plan view, the flexure of rectangular shuttering between a closed, flat-pack configuration, and an open configuration for use; Figure 2a illustrates rectangular shuttering according to Figure 1, and 2 Figure 2b is an enlarged partial view of one of the corners of the shuttering illustrating the bracing arrangement; Figure 3 is a schematic perspective view from one side and from above of a square shuttering arrangement, further illustrating the use of spirit levels; Figure 4a is a perspective view corresponding to Figure 3, and Figure 4b is an enlarged partial view of one corner of the arrangement of Figure 4a, illustrating the hinge arrangement; Figure 5 illustrates, in an exploded view, components of a hinge arrangement for use in the shuttering of Figures 1 to 4; Figure 6 is a perspective view of an alternative hinge for the shuttering of Figures 1 to 4; Figure 7 is a perspective view corresponding to Figure 3, further illustrating ground-levelling means; Figures 8a to 8c correspond to Figures la to lc and illustrate alternative angles for the end faces of the abutting shutter elements; Figures 9a to 9c correspond to Figures 1 a to 1 c and illustrate apparatus with six shutter elements for forming a rectangle, and Figure 10 is a view of a six-element shuttering apparatus for an irregular shaped polygonal shuttering.

A pre-assembled shuttering arrangement is shown in Figures la to lc, and comprises two pairs of elongate shutter elements of different lengths, hinged together at their opposed ends to form a flexible rectangular arrangement. The unit may be collapsed as shown in Figure la into a flat-packed configuration for ease of transport, with the shutter elements parallel to each other. Opening the arrangement out through the intermediate position shown in Figure lb, the unit assumes a rectangular structure as shown in Figure 1 c, at which the end surfaces of 3 the shutter elements abut one another. The end surfaces in this example are cut at 450 so as to form mitred corners. Also in this arrangement, there are two internal hinges at opposed corners, and two external hinges at the other opposed corners.

In order to prevent flexure of the arrangement of Figure l c once it has been assembled on site, a bracing arrangement is used, as shown in Figure 2b. The shutter elements are pre-drilled with holes 22, for receiving the angled ends of a rigid bar 21. The bar 21 forms a diagonal brace across one of the corners, as shown. Corresponding braces may be fitted to the other corners. The braces are then of course above the upper surface of the shuttering arrangement, so that they do not interfere with the concrete or other filter. The braces in this example are readily removable for re-use of the shuttering.

Figure 3 is a schematic perspective view of a square arrangement otherwise corresponding to the rectangular arrangement of Figures 1 and 2. The height of each shutter element in relation to its thickness is apparent from Figure 3. In this example, a spirit level device 31 is permanently inset into a horizontal edge surface of one of the shutter elements, and a similar spirit level device is shown inset into a vertical face of each of two other shutter elements. However, it will be apparent that many different positions and numbers of spirit level devices would be possible.

The bracing means could incorporate a spirit level.

One possible hinging arrangement is shown in Figures 3 and 4a, and is shown enlarged in Figure 4b. Each corner hinge has two inter-engaging components 41, joined by a centre pin 42 which has a knob-shaped handle for easy removal of the pin. Figure 5 illustrates, in an exploded view, a hinge similar to that of Figure 4, with separate hinge components 51 and 52 which rotate about a pin 54 having a handle 53. In this example, the pin 54 is screw-threaded so as to form a tight fit in the cylindrical receiving portions of the hingee,Iements 51 and 52. The 4 handle 53 may be linked to the pin 54 through a deliberately weakened joint to allow the handle 53 easily to be broken off after assembly.

An alternative hinge is illustrated in Figure 6, and may be formed of metal or plastics material with an integral hinge defined by a thinner portion. However, there is not necessarily a need for a thinner portion. As illustrated, the hinge may have preformed apertures for the fixing of nails or screws. There may also, or as an alternative to the other fixtures, be a spiked material 61 on one surface of each hinge element, to enable the hinge to be secured by hammering.

In order to level the shuttering at the appropriate height above the ground, and to adjust it on site, at least one, and preferably all, of the shutter elements are formed with couplings 73 which may be secured to the side of the element or may -be formed integrally with the element. A ground peg 71 is provided for each such coupling, and the arrangement is such that the peg penetrates a bore in the coupling 73 in the vertical direction. A hand-tightenable securing screw 72 enters the coupling 73 transversely in order to tighten against the peg 71 at the appropriate position of the peg.

An alternative arrangement is shown in Figures 8a to 8c in which the end faces of the shutter elements are square. The hinge arrangements correspond to those of Figure 1.

A further possibility is shown in Figures 9a to 9c, in which six shutter elements of equal length are connected endwise to form a flexible hexagon which may be formed into a rectangle twice as long as it is wide. In this example, the abutment midway along the longest sides of the rectangle occurs between right angled end faces, whereas the corners are mitred at 450. Two opposed hinges are internal, whereas the other four hinges are external.

Alternative polygonal, such as hexagonal, shapes are all possible, with end faces of shutter elements designed to abut once the desired shape is attained. An irregular polygonal shuttering is shown in plan view in Figure 10, in which there are shutter elements of three different lengths: two pairs of each length. In this example, the hinging is all external.

In use, the shuttering is transported to the site, either in a flat-pack configuration or else disassembled. Once the ground has been prepared, the shuttering is assembled in situ, and the hinge pins inserted if necessary. Once the arrangement has been opened out to the correct final configuration, the bracing is applied as necessary, and ground pegs inserted through the couplings. The height of one or more of the shutter elements is then adjusted, whilst monitoring the spirit level devices. If there were handles on the centre pins of the hinges, then. these or the entire pins could be removed if required to be removed. Finally, the concrete or other filler is then introduced into the shuttering and when it has solidified the shuttering may be removed if required for re-use, or left in place. The removability of the hinge pins assists in dismantling the structure.

As an alternative to the hinges illustrated, it would also be possible to use simple flexible materials such as plastics webs or metal bands to join the shuttering material at the pivot points.

It will be appreciated that each shutter element could be formed with just one hinging means, at one end only, for assembly end-to-end on site.

It may also be desired to recess the hinges so that the cast base or other foundation is not spoilt by the impression made by the hinges. For this purpose, if there is a centre pin then it could be removed using the handle, before casting.

Plastics or metal or metal alloy materials for the shuttering would provide the most 6 long-lasting re-usable systems, but permanent versions could also be made of wood for aesthetic value, or any other synthefic or natural material.

The shutter elements need not be of fixed length nor of solid, unitary construction. The use of extendable or telescopic elements would, in particular, help to define a whole range of irregular shaped shuttering, and is probably most easily implemented with plastics elements. Each elements could offer a printed rule or suchlike to measure the desired length, and the rule could be situated at an appropriate place depending on the permanency of the apparatus. This would still avoid the need for tools.

The coupling between ground-levelling pegs and shutter elements could be internal to the elements, or could be part of a joint between two components of a shutter element which are joined end to end rigidly. Thus there could be a vertical opening for a peg through such a joint.

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Claims (20)

1. Shuttering apparatus comprising at least three elongate shutter elements each with hinging means at at least one of its ends for mutual connection end to end in use, the end faces of the elements being cut at angles such that, when hinged together end to end in use, the pairs of opposed end faces may all be brought into abutment so that the hinged assembly is rigid and defines a predetermined polygonal shuttering configuration.

2. Shuttering apparatus according to Claim 1, in which there are at least four shutter elements all hinged together such that the shuttering is flexible between a flat, closed configuration, with the shutter elements parallel, and a fully open configuration defining a polygon, at which the pairs of end faces of the shutter elements are all in mutual abutment.

3. Shuttering apparatus according to Claim 2, in which there are four shutter elements, internally hinged at two opposed corners and externally hinged at the other two opposed corners.

4. Shuttering apparatus according to Claim 3, in which the end faces of the elements are angled to form mitred corners.

5. Shuttering apparatus according to Claim 3, in which the end faces of the elements are square, transverse to the direction of elongation of the shutter elements.

6. Shuttering apparatus according to any preceding claim, in which the shutter elements are sized and arranged to form an irregular polygon in use.

7. Shuttering apparatus according to any preceding claim, comprising means for bracing two of the shutter elements together to maintain the shuttering at its predetermined configuration for shuttering, with the end faces in abutment.

8 8. Shuttering apparatus according to Claim 7, in which the bracing means comprises a bar, at least one pair of adjacent shutter elements being formed with holes for receiving the bar.

9. Shuttering apparatus according to any preceding claim, in which one or more 5 of the shutter elements is or are made in part or entirely from plastics or wood or metal or metal alloy materials.

10. Shuttering apparatus according to any preceding claim, in which at least one of the shutter elements incorporates a spirit level device.

11. Shuttering apparatus according to Claim 7 or 8, in which the bracing means incorporates a spirit level device.

12. Shuttering apparatus according to any preceding claim, in which the hinging means co-operate to form a hinge with a removable centre pin, such that each hinge may be dismantled for re-use.

13. Shuttering apparatus according to Claim 12, further comprising a plurality of centre pins for the hinges.

14. Shuttering apparatus according to Claim 13, in which the removable hinge pins have a handle or other appropriate means for grasping the pins for removal.

15. Shuttering apparatus according to any preceding claim, further comprising means for securing the assembled shuttering at a predetermined level on the ground.

16. Shuttering apparatus according to Claim 15, in which the levelling means comprises, for each of one or more of the shutter elements, a ground-engageable peg and a coupling secured to or integral with the shutter element for connecting the shutter element to the peg at a selectable height.

17. Shuttering apparatus substantially as described herein with reference to the accompanying drawings.

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18. A method of shuttering using shuttering apparatus according to any preceding claim, comprising arranging the shutter elements end to end in a closed loop configuration and flexing the configuration to bring the said pairs of opposed end faces all into abutment and thereby to set the assembly at the predetermined polygonal configuration.

19. A method according to Claim 18, further comprising bracing at least one pair of adjacent shutter elements so as to secure the shuttering at the predetermined polygonal configuration.

20. A method of shuttering substantially as described herein with reference to 10 the accompanying drawings.