AU2008202741A1 - A Shutter - Google Patents

Description

00 A SHUTTER

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TECHNICAL FIELD This invention relates to a shutter for use in a formwork system. In particular the invention relates to a shutter for use when pouring concrete or other mouldable materials, although other uses are envisaged.

00 BACKGROUND ART A significant amount of the cost of forming a concrete slab is incurred in erecting and dismantling a formwork to contain the poured concrete while it cures and hardens. Furthermore, the quality of the moulded surface of the finished concrete slab depends largely on the quality of construction of the formwork.

A formwork typically includes a number of panels, often called shutters, which are linked together and braced in order to form a structure around the perimeter of the proposed concrete slab. In general, a formwork is constructed by: placing each shutter in turn in its correct position; and 0 supporting each shutter while bracing is attached to the shutter, without the shutter moving from its correct position; and Saligning adjacent shutters and connecting them together so that the resulting formwork has the correct shape and structure to form a mould for the concrete, and to minimise seepage of concrete between the side edges of adjacent shutters.

The type of shutter used depends to some degree on the size of the slab to be poured, i.e. the weight of concrete to be contained by the shutter.

00 O In some situations formwork is required to support vertical slabs of concrete which Fmay involve shutters several metres tall. Formwork for these situations is highly specialised and typically requires a crane and specialised skills to construct.

However, most formwork involves the use of smaller shutters which generally may be manipulated and erected manually. The following discussion applies mainly to such shutters.

00 Shutters can be formed in a wide variety of shapes and sizes depending on the Sshape and size of the finished concrete. While in most cases a shutter has a rectangular shape, with a smooth planar contact surface facing the concrete when poured, other forms and surfaces are common. For example, a curved surface can be used to produce a curved section of concrete. In some instances it may be that a design is to be formed on the side of the concrete slab, in which case the contact surface of the shutter may include surface features to form the design.

In all cases a shutter must be sufficiently strong and rigid to enable it to withstand the force of the concrete pushing against the shutter without buckling or otherwise deforming.

Strength and rigidity can be provided to a shutter by including a reinforcing frame.

Typically a sheet of material is attached to the frame to form a contact surface for the poured concrete. Both wooden and metal framed panels are common.

In all cases, however, a shutter once positioned must be held in place while the required bracing is attached. A major disadvantage of conventional shutters is that even if the shutter can stand unsupported on its bottom edge, it is easy knocked over or moved if impacted, as can often occur during attachment of bracing.

To overcome the instability of an unsupported shutter, a shutter is commonly held manually in the correct position or, in some cases (particularly for larger panels), a 00

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machine such as a crane may be used to support the shutter while the bracing is attached. As a result it usually takes more than one person to erect each shutter, one holding the shutter in place while the other attaches the bracing. This adds considerably to the time and labour costs of erecting a formwork.

Bracing for a shutter is commonly formed by attaching a brace to the rear of the shutter the opposite side to the contact surface for the concrete) and securing 00 it to the ground or base surface at some distance from the shutter.

For wooden shutters a brace is commonly a length of wood, one end of which is nailed to the shutter and the other end of which is nailed to a wooden peg that is driven into the ground in order to provide an anchor point for the bracing.

Metal framed shutters (of a size that may be handled manually) commonly include a wooden section attached to the frame to which a wooden brace may be attached.

The method of bracing metal framed shutters is therefore generally the same as for wooden framed shutters.

In general, the position at which the braces are attached to a shutter, and the angle of the brace (relative to the surface of the shutter) when attached, must both be carefully measured in order to provide the required support for the shutter when under load.

Often new bracing braces and pegs are constructed for each job. This usually involves the use of a power saw can be noisy and a potential safety hazard for workers. It also requires the use of skilled labour, as the braces must be formed with the correct angle cut at the end to be attached to a shutter, and cut to length so that the formed brace spans the separation between the shutter and the anchor peg. Typically this involves hiring labour with carpentry skills at a higher cost than unskilled labour.

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There are a number of disadvantages of using nails to attach braces to shutters.

These include difficulty in nailing the pieces together accurately when assembling the formwork and in removing the nails when disassembling it. In practice removing the nails often involves knocking the braces off the shutter, which may damage both the brace and the shutter, thus reducing their useful lifetime.

Further, as the braces for a particular panel will generally be attached in the same 00 locations, with repeated use the number of nail holes in these locations increases.

Eventually it may become difficult to securely nail a brace to the shutter in the desired location, which limits the useful lifetime of the shutter.

Additional time and labour is required to remove nails from the braces, pegs and shutters once dismantled. The nails are often bent during the dismantling and removal process and generally end up discarded on the ground where they present a safety hazard to people in the area.

Following dismantling of a wooden formwork it is common for the site to become littered with discarded and often broken pieces of wood, as well as nails, which may lead to an unsafe work site.

As each shutter is put in place it must be aligned carefully with the adjacent shutters and secured in some manner to them. Care, and therefore time, is required to ensure that the contact surfaces in particular are properly aligned in order to provide the correct shape to the poured concrete.

The sides of the shutters also need to be held in close contact so that concrete cannot seep between them. This is commonly done by clamping together the sides of adjacent shutters, or by using tie rods extending between them.

It is a disadvantage of conventional shutters that they may easily become 00 O misaligned during construction of formwork, a situation which, if not corrected, may Fresult in an unsightly and unwanted surface on the finished concrete slab.

SIt is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any 00 Sreference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

Further aspects and advantages of the present invention will become apparent from the ensuing description, which is given by way of example only.

00 DISCLOSURE OF INVENTION

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According to one aspect of the current invention there is provided a shutter for a formwork system characterised in that the shutter is configured to retain a locating pin such that the locating pin can hold 00 the shutter with respect to a base upon which the shutter is placed.

According to another aspect of the present invention there is provided a locating pin for a formwork system, characterised in that the locating pin is configured to hold a shutter with respect to a base upon which the shutter is placed.

According to another aspect of the current invention there is provided a method of installing a shutter for a formwork system at a desired position, the formwork system having one or more locating pins, and one or more shutters configured to receive one or more locating pins characterised by the steps of a) placing a shutter in the desired position with respect to a base, and b) inserting the locating pin with respect to the shutter, and c) fixing the locating pin relative to the desired position so that the locating pin secures the shutter with respect to the base.

Formwork, as used throughout this specification, should be understood to refer 00 O primarily to a temporary structure used to hold concrete or similar materials during Scuring and hardening. However, it is envisaged that a formwork according to the

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present invention may be used for other purposes, such as to form a fence or barrier. Formwork is typically composed of a number of components, including shutters and bracing for the shutters, and the various fasteners and supports used to hold the formwork together. A formwork system refers to a particular way in Swhich the components are used in constructing a formwork.

(Ni 00 SThroughout this specification reference will be made to a formwork (and shutters) for use with concrete. However, it will be appreciated that a formwork may be used as a mould for many other materials, such as rammed earth, and that reference to concrete only should not be seen as limiting.

A shutter includes a faceplate, a surface of which is in contact with concrete during use. A faceplate of a shutter may be planar or curved as required to provide the correct contour to the concrete.

A shutter for use in forming a corner, to be referred to as a corner piece, may include a faceplate having more than one planar section. For example a faceplate for a corner piece may have two planar surfaces meeting at a common edge so as to form a mould for a corner.

It will be appreciated that the present invention may be applied to a faceplate and shutter of any shape.

The contact surface of a faceplate may be smooth or contain surface features to be moulded into the concrete as required.

A shutter may be formed as a faceplate only, for example as a thin slab of material, such as a wooden plank or a metal sheet. However, a shutter formed in this 00

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manner may have sufficient rigidity to be part of a formwork for a thin slab of concrete only.

In a preferred embodiment the shutter includes a frame.

A frame may be fixed to a faceplate in order to support, reinforce and provide rigidity to a faceplate, particularly when the faceplate is under load from a

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substantial amount of concrete placed against it.

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O A frame may be of any suitable configuration, and may be constructed from wooden beams or from metal, for example steel box section, or any other material that can provide a rigid frame for the faceplate.

The invention will be illustrated with reference to a rectangular shutter. However, it will be appreciated that the present invention may be applied to shutters of various shapes, including corner pieces, and that reference to a rectangular shutter only should not be seen as limiting.

A rectangular shutter has a bottom edge, being the edge that in use is placed on a base.

Reference to a base for a shutter should be understood to refer to a surface on which a shutter is placed.

A common base for a shutter is the ground.

Reference will be made throughout the specification to a shutter for which the base is the ground. However a base for a shutter may be any solid surface, such as (without limitation) a concrete or bitumen pad, or a timber floor, so that reference to a shutter where the base is the ground only should not be seen as limiting.

The edge opposite to the bottom of the shutter will be referred to as the top of the 00

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shutter. A rectangular shutter also has two side edges.

In a preferred embodiment the shutter includes a retainer.

Reference to a retainer throughout this specification should be understood to mean any device used to locate, retain and hold in place with respect to a shutter, a 5 locating pin.

00 In a preferred embodiment the retainer is an aperture.

An aperture in a shutter may be configured to have a similar cross sectional shape as a locating pin but with a slightly larger perimeter than the pin. An aperture may be configured to allow a locating pin to pass freely through it but to limit lateral movement of the locating pin in the retainer.

Preferably an aperture is formed in the frame of the shutter.

In other embodiments a retainer may be a bracket attached to the shutter, the bracket configured to retain a locating pin inserted through it.

Throughout this specification a locating pin should be understood to refer to any rigid elongate section of material which may be fixed relative to a base and may be configured to be retained by a retainer on a shutter to hold the shutter in position with respect to the base.

The dimensions of a locating pin for use with a shutter may vary depending on the size and weight of the shutter. In all cases one or more locating pins of a suitable size and strength are retained by a shutter so as to hold the shutter securely in place relative to a base.

In a preferred embodiment the locating pin includes an elongate rod of sufficient length to extend from the top edge of the shutter to the bottom edge of the shutter 00 and into a base.

A locating pin in this embodiment may be in the form of a rigid shaft, one end of which may be configured to engage with the ground and the other end of which may be configured as a head.

Typically the ground engaging end of the locating pin is tapered, making it relatively easy for the locating pin to penetrate the ground and to be moved to a 00 Odepth sufficient to fix it in the ground.

In some embodiments, the ground engaging end may be configured as a tapered screw, so that the locating pin may be drilled into the ground using an action similar to that of an auger. This would require the aperture to have a sufficiently large enough cross-section to allow rotation of the locating pin.

The head of a locating pin may be configured to facilitate engagement of the locating pin through the retainers and into the ground.

Preferably the head of the locating pin is configured to provide a surface that may be impacted on to drive the locating pin through the retainer and into the ground.

Preferably the head of the locating pin may extend substantially beyond the radial width of the shaft of the locating pin. A head that is larger in radial dimension than the shaft may provide a more suitable target surface for impacting.

Use of a head that is wider than the shaft may also reduce the severity of injury should anyone fall onto the locating pin, thus reducing a potential hazard for workers.

In some embodiments the head of the locating pin may be configured to engage with a tool, such as a spanner, so that the locating pin may be rotated about the 00 axis of the shaft. For example, this may be used in conjunction with a ground Sengaging end in the form of a screw to facilitate penetration of the pin into (and removal of the pin from) the ground.

A head may also be configured to be gripped by a tool in order to facilitate removal of the locating pin from the ground and shutter. For example, a head may include a surface that a tool may engage in order to prise the pin away from the ground 00 and shutter.

In a preferred embodiment the locating pin includes a flange configured to bear against a surface of a shutter when in use in the formwork system.

In a preferred embodiment the flange is located between and separated from the head and the ground engaging end of the locating pin.

A flange on the shaft of a locating pin may be used to bear against a surface of the frame of the shutter, thus holding the shutter under pressure against the ground.

A flange may also provide a measure of the engagement of the locating pin through the retainers in the shutter and into the ground. For example, it may be preferable to ensure that the locating pin is inserted at least a pre-set distance into the ground to provide a secure support for a shutter. The flange may be located at a point along the shaft such that when the flange bears against an upper surface of a shutter the locating pin will be inserted into the ground by the pre-determined distance. This arrangement may overcome any uncertainty regarding the degree of support provided, as can occur with some prior art formwork systems, and therefore give a measure of consistency when erecting a formwork system.

When erecting a formwork a shutter may be placed in the required position on the ground. A locating pin may be inserted, ground engaging end first, through a 00

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retainer on the shutter and into the ground. The locating pin may be driven into the ground until the flange bears against a surface of the frame.

Preferably, additional, substantially identically formed locating pins may be inserted through the retainers in the shutter and into the ground as required, so as to secure the shutter with respect to the ground.

N An advantage of using substantially identical locating pins is that, when fully 00

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Sengaged as described above, the action of each locating pin on the shutter is uniform. Each pin is driven to essentially the same depth into the ground and each pin exerts substantially the same pressure onto the shutter to hold it in place. The uniform pressure exerted on the shutter by each locating pin may reduce any unwanted twisting of the shutter that may occur if the action of the engaged locating pins varied across a shutter. A further advantage may be that any of the identical locating pins can be used with shutters of the same size and shape, which may save time spent otherwise seeking the correct locating pin to use with a specific shutter.

According to another aspect of the present invention there is provided a locating bracket for a formwork system characterised in that the locating bracket is configured to hold a shutter in place with respect to a base when the locating bracket is fixed to that base.

Reference to a locating bracket throughout this specification should be understood to refer to a structure that may be fixed in position relative to a base. A locating bracket may be configured to retain a locating pin.

A locating bracket may be used to hold a shutter in place in situations where the base is such that it may not be appropriate to engage a locating pin directly into the

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base. This may occur when a shutter is erected on a base other than the ground, for example onto a concrete or bitumen pad.

Preferably a locating bracket may include a bracket locating pin.

For example, a shutter may be placed in position on a concrete pad used as a base. A bracket locating pin on a locating bracket may be inserted into a retainer 00

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Oon the shutter. The locating bracket may then be fixed in position with respect to the concrete pad, for example by a bolt.

In alternative methods, a locating bracket may be fixed in position with respect to the base and a shutter placed onto the locating bracket by engaging a retainer on the shutter with a bracket locating pin on the locating bracket.

In other embodiments a locating bracket may include a retainer, typically in the form of an aperture. The locating bracket may be configured such that the aperture in the locating bracket may be aligned with an aperture on the shutter when the locating bracket is fixed in place on the concrete pad. A locating pin, configured to engage with the locating bracket, may be inserted through the aligned apertures in the shutter and locating bracket so as to hold the shutter in place with respect to the locating bracket, and hence with respect to the concrete pad base.

The use of a shutter configured to retain a locating pin (either as a separate item or as part of a locating bracket) in order to hold the shutter in place with respect to the base may overcome some of the disadvantages of the prior art shutters.

In particular, with the locating pins engaged the shutter may be supported and held fixed in a stable position with respect to the base without the need to be held 00

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manually. With this arrangement one person may fix a shutter in place, which may be more convenient and efficient as well as reducing labour costs.

The added stability of the shutter when held by the locating pins also means that it is less likely that the shutter will be shifted from its correct position during attachment of bracing. This may reduce the time and cost of erecting the shutter ias less time is spent realigning the shutter each time it is knocked or otherwise OO moved from its correct position.

In a preferred embodiment the shutter includes a bracing attachment.

In a preferred embodiment the bracing attachment is a brace pin.

A brace pin may be a shaft extending from the frame of the shutter, the brace pin being oriented substantially in the plane of the frame and substantially parallel to the bottom (or top) edge of the shutter.

A brace pin may be configured to engage with an aperture in an end of a brace used to brace the shutter. A brace may be attached to the shutter by inserting a brace pin through the aperture in the brace.

With the brace pin oriented as described above the weight of the shutter (and contained concrete when poured) is directed back along the brace. As a result there may be no sideways force exerted on the brace, which may therefore be held in place on the brace pin without the need for further fastening, for example by use of a nut.

This arrangement means that a bracing brace may be attached to a shutter in one simple motion, without the need for nailing or use of other fasteners. This may significantly reduce the time needed to attach the brace, thus saving costs. It also reduces the demand for skilled labour, as anyone may be able to insert the brace 00

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pin through the aperture on the brace in order to secure it.

However, for additional safety a brace pin may include an aperture extending radially through the brace pin. A peg, either solid or in the form of a cotter pin, may be inserted into the aperture after the brace has been fitted, so as to prevent the brace from moving back off the brace pin.

N The time taken to dismantle the bracing from the shutter is also reduced as all that 00

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Ois involved is to remove the peg (if fitted) and move the brace so that it slides off the brace pin. This overcomes a major problem of removal of nails or nuts etc., which is a time consuming aspect of prior art formwork. It also means that there are no discarded nails or nuts left on the ground, thus improving the working conditions on the site.

Furthermore, there is no degradation of the shutter or brace with repeated assembly and dismantling. Thus shutter lifetime is increased, again reducing operating costs.

Brace pins may be located on the shutter at the correct height and spacing with respect to the shutter to provide appropriate engagement points for bracing the shutter when erected, thus reducing the need for measurement before assembly.

In alternate embodiments the bracing attachment may be an aperture in the shutter (preferably in the frame of the shutter). In such embodiments a brace may include a brace pin configured to engage with the aperture in the shutter.

In a preferred embodiment a side edge of the shutter is configured to engage with a side edge of another shutter placed adjacent to it.

In a preferred embodiment a first side edge of the shutter is configured to include a channel.

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In a preferred embodiment a second side edge of the shutter is configured to include a protrusion configured to engage with the channel.

The channel in the first side edge of the shutter and the protrusion on the second edge may be complementary shapes, such that when brought together the protrusion substantially fills the channel.

SFurthermore, the channel and protrusion are located in substantially the same 00

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Oposition relative to their respective side edges.

Two similar shutters configured in this manner may be placed so that a protrusion on an edge of the first shutter is adjacent to a channel on an edge of the second shutter. The panels may be brought together so that the protrusion on the edge of the first shutter fills the channel on the edge of the second shutter. As the location of the channel and protrusion is the same with regard to their respective shutters, the result is that the faceplates of the two shutters will be aligned.

The use of shutters with complementary edge conformation may substantially reduce the time and care required to align the shutters as compared with manual alignment of the prior art shutters.

In a preferred embodiment the channel in the first side edge has a rectangular cross section and the second side edge has a complementary rectangular protrusion.

In other embodiments the cross section of the channel in the first edge may have other shapes, such as an open sided trapezoid, as used in dovetail joins which are well known in carpentry.

An advantage of a square cross section is that the two complementary edges may be simply butted together to align the shutters.

00 SIn contrast, dovetail styled complementary edges may be engaged by sliding the trapezoid protruding section on an edge of one shutter into the channel on an edge

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of another shutter. This involves some additional effort over engagement of square sections, but does have the advantage of locking the edges of the shutters together with regard to sideways movement.

In some embodiments a shutter may be formed with a channel formed in both the 00 first and second sides, and other shutters formed with a protrusion at each side.

SWhile this arrangement may be used to erect a formwork as described herein, it may be less convenient as the adjacent shutters need to be selected so that a shutter with a channel on each side is matched with an adjacent shutter with a protrusion on each side.

In other embodiments, both the first and second side edges may include a channel. In these embodiments, when adjacent shutters are butted together, a block, having a complementary shape to the channels, may be inserted through the channels, thus holding the shutters aligned.

In a preferred embodiment the method of installing a shutter for a formwork system includes the further steps of d) attaching one or more braces to the shutter by inserting a brace pin on the shutter through an aperture in the end of the brace, and e) fixing the end of the brace not attached to the shutter to the base.

In a preferred embodiment the method of installing a shutter for a formwork system includes the step of f) securing the brace by inserting a peg through an aperture in the brace pin.

00 In a preferred embodiment the method of installing a shutter for a formwork system includes the further steps of

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g) adding adjacent shutters by engaging complementary edge sections of each shutter so as to align a faceplate of each shutter, h) fixing the added shutters in place by repeating steps b) to f) for each added shutter, 00 Swherein steps g) and h) are repeated until the complete formwork is erected.

According to another aspect of the present invention there is provided a kitset for a formwork system including at least one shutter, and at least one locating pin, wherein the locating pin is configured to engage with a retainer on the shutter and with a base for the formwork, such that the shutter is held in place with respect to the base.

In a preferred embodiment the kitset includes a brace configured to engage with a bracing attachment on the shutter.

In a preferred embodiment the kitset includes a locating bracket which is to be fixed upon a base, wherein the locating bracket is configured to hold the shutter in place with respect to a base once the locating bracket is fixed upon the base.

The present invention provides advantages over prior art formwork systems in 00 0 several key areas of assembly and dismantling of a formwork. The shutters are Fconfigured to retain a locating pin, which may be used to hold the shutter in place

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with respect to the ground. The shutters also include brace pins to which a brace may be easily attached without the need for nails or other fasteners. The edges of the shutter are configured with a profile which, when engaged with a complementary profile on an adjacent shutter, may ensure the correct alignment of Sadjacent shutters.

00 SEach of these features simplifies the process of assembling or dismantling a formwork, thus providing significant savings in time and labour cost. The assembly and dismantling process may be carried out without any damage being incurred to the component parts, thus extending the useful lifetime of the formwork system and substantially reducing the amount of debris left on site following dismantling of the formwork.

BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1 shows a shutter according to a preferred embodiment of the present invention; Figure 2 shows a locating pin and a shutter according to the embodiment of Figure 1; Figure 3 shows a locating bracket and a shutter according to the embodiment of Figure 1; Figure 4 a shutter with a locating pin and bracing brace according to the 00 O embodiment of Figure 1; and ;Figure 5 shows a shutter according to another aspect of the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION A shutter, according to a preferred embodiment of the present invention, in the 00 form of an approximately 2400 x 600 mm rectangular panel, is generally indicated Sby in Figure 1.

The shutter has a faceplate the surface of which forms a contact surface for the poured concrete.

The shutter includes a frame which provides reinforcing to the faceplate The frame includes a retainer in the form of an aperture configured to retain a locating pin.

A locating pin, in the form of an elongate shaft, is generally indicated by in Figure 2.

The locating pin has an end configured to penetrate the ground.

The end of the locating pin distal to the ground penetrating end has a head The head has a flattened upper surface to provide a suitable surface to hit in order to drive the locating pin into the ground.

A flange extends from the shaft (10) of the locating pin at a distance from the ground penetrating end and the head The separation of the head from the flange is used to enable a tool (not shown) to grip the head in order to facilitate removal of the locating pin 00 O when dismantling the formwork.

SIn use, a shutter is placed on the ground (indicated by the dashed lines in N the desired location, as illustrated in Figure 2 Note only an end section of a shutter is shown in Figure 2 A locating pin is inserted, ground penetrating end first, through an aperture in the frame at the top edge of the shutter The locating pin is then 00 Sinserted through a second aperture in the frame at the bottom edge of the shutter and then driven into the ground (23) below the shutter.

The locating pin is driven into the ground, usually by hitting the head of the locating pin until the flange bears against the top edge of the frame This process is repeated for other locating pins and retainers until the shutter is secured in place relative to the ground.

Formwork for a higher slab may be erected by placing a second shutter, similar to that described above, directly on top of the first shutter, such that the bottom edge of the second shutter is in contact with the top edge of the first shutter.

The two stacked shutters may be held in place by a locating pin of a similar configuration but twice the length of that shown in Figure 2. The shaft in this instance has sufficient length to span from the top edge of the second shutter to the bottom edge of the first shutter and into the ground.

The first and second shutters are aligned so that the double locating pin can be inserted through apertures (4 and in each shutter and into the ground.

Clamps (not shown) may be used to clamp the bottom edge of the second shutter to the top edge of the first shutter in order to hold the edges of the stacked shutters 00 Stogether.

SA locating bracket, generally indicated by arrow is shown in Figure 3. The N locating bracket (11) is formed from a section of angle iron (12).

The locating bracket (11) includes a bracket locating pin (15) in the form of a rigid rod. The bracket locating pin (15) extends from a metal plate (14) that is fixed, N typically by a weld, to an edge of the angle iron (12).

00 SThe locating bracket (11) includes apertures (13) into which bolts (16) are inserted to fix the locating bracket with respect to the base (17).

The position of the bracket locating pin (15) with respect to the angle iron (12) is such that the bracket locating pin (15) can engage with an aperture on the bottom edge frame of a shutter when the locating bracket (11) is fixed in place.

To erect a formwork on a solid base (other than the open ground), a shutter is placed onto the surface of the base. A locating bracket (11) is placed against the frame at the bottom edge of the shutter so that a bracket locating pin (15) is inserted into an aperture (not shown in Figure 3 formed in the frame The locating bracket (11) is then fixed in place with respect to the base (17) by fixing a bolt (16) through an aperture (13) in the angle iron (12) and into the base (17).

A brace pin (18) is attached to an upright member of the frame of a shutter as shown in Figures and A brace (19) is used to brace the shutter The brace (19) includes an aperture having a radius slightly larger than the radius of the brace pin so that the brace pin (18) may be inserted through the aperture (20) in the brace (19) in order to attach the brace (19) to the shutter 00 SThe brace pin (18) includes an aperture (21) into which a peg (22) may be inserted Fafter the brace (19) has been engaged with the brace pin The peg (22) is configured to prevent the brace (19) from moving along (and off) the brace pin (18) until the peg (22) is removed from the aperture (21).

After a shutter has been fixed in place on a base, either with a locating pin driven into the ground or by a locating pin (15) on a locating bracket, one or more 00 braces are attached to the shutter as described above. The end of the brace distal Sto the attachment to the shutter may be anchored to the base using conventional techniques (eg, fixing to an anchor peg or bolting a plate on the end of the brace into the base).

Adjacent shutters are added and aligned by engaging complementary edge sections on each shutter.

A shutter with a side edge configured as a protrusion (24) is shown in Figure 1 The protrusion has a square cross section.

A shutter with a side edge configured as a complementary channel (25) is shown in Figure 1 The protrusion (24) and the channel (25) are configured such that when the corresponding edges are butted together the protrusion (24) fills the channel and the surfaces of the respective face plates (2 and of the shutters (1 and 1') are aligned.

A shutter, in the form of a corner piece (26) for a square corner, is shown in Figure The corner piece (26) has a face plate having a first planar surface (27) and a second planar surface (28) which meet at a common edge (29).

The corner piece (26) includes a frame (30) and a retainer in the form of an 00 aperture (31) in the frame (30) configured to retain a locating pin (not shown).

SA first edge of the corner piece (26) includes a protrusion (32) with a square cross section, configured to engage with a complementary channelled edge of another shutter.

A second edge of the corner piece (26) includes a channel (33) with a square Scross section configured to engage with a complementary protrusion on the edge 00 of another shutter.

The corner piece (26) also includes a brace pin (not shown).

The complete formwork is erected using the following steps: a) placing a shutter in the desired position with respect to a base, and b) inserting one or more locating pins through retainers in the shutter, and c) fixing the one or more locating pins relative to the desired position so that the locating pins secure the shutter with respect to the base, and d) attaching one or more braces to the shutter by inserting a brace pin on the shutter through an aperture in a first end of the brace, e) securing the brace (if required) by inserting a peg through an aperture in the brace pin, and f) fixing a second end of the brace to the base, and g) adding adjacent shutters by engaging complementary edge sections of each shutter so as to align the surfaces of the face plates of each shutter, and h) fixing the added shutters in place using steps a) to f) above.

00 Steps g) and h) are repeated until the complete formwork is erected.

SThe formwork is dismantled by reversing the above steps.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope of the appended claims.

00

Claims (23)

1. A shutter for a formwork system characterised in that 00 the shutter includes a retainer to retain a locating pin such that the locating Spin can hold the shutter with respect to a base upon which the shutter is placed.

2. A shutter as claimed in claim 1 wherein the retainer is an aperture.

3. A shutter as claimed in either of claims 1 or 2 wherein the shutter includes a bracing attachment.

4. A shutter as claimed in claim 3 wherein the bracing attachment is a brace pin. A shutter as claimed in any one of claims 1 to 4 wherein a side edge of the shutter is configured to engage with a side edge of another shutter placed adjacent to it.

6. A shutter as claimed in claim 5 wherein a first side edge of the shutter includes a channel.

7. A shutter as claimed in claim 6 wherein a second side edge of the shutter includes a protrusion configured to engage with the channel.

8. A locating pin for a formwork system, characterised in that 00 the locating pin is configured to hold a shutter with respect to a base upon which the shutter is placed. S9. A locating pin as claimed in claim 8 wherein the locating pin is configured as an elongate rod of sufficient length to extend from a top edge of a shutter to a bottom edge of the shutter and into a base.

10. A locating pin as claimed in either of claims 8 or 9 which includes a flange. 00

11. A locating pin as claimed in claim 10 wherein the flange is located between and separated from a head and a ground engaging end of the locating pin.

12. A locating bracket for a formwork system characterised in that the locating bracket is configured to hold a shutter in place with respect to a base when the locating bracket is fixed to that base.

13. A locating bracket as claimed in claim 12 including a locating pin.

14. A formwork system including at least one shutter as claimed in any one of claims 1 to 7. A formwork system including at least one locating pin as claimed in any one of claims 8 to 11.

16. A formwork system including at least one shutter as claimed in any one of claims 3 to 7 which includes at least one brace configured to engage with the bracing attachment.

17. A formwork system including at least one shutter as claimed in any one of claims 1 to 7 which includes a locating bracket configured to hold the 00 O shutter in place with respect to a base upon which the locating bracket, in Suse, is fixed. ;Z

18. A method of installing a shutter for a formwork system at a desired position, the formwork system having one or more locating pins, and one or more shutters configured to receive one or more locating pins characterised by the steps of 00 a) placing the shutter in the desired position with respect to a base, and b) inserting the locating pin with respect to the shutter, and c) fixing the locating pin relative to the desired position so that the locating pin secures the shutter with respect to the base.

19. A method as claimed in claim 18 including the steps of d) attaching a first end of one or more braces to the shutter by inserting a brace pin on the shutter through an aperture in the end of the brace, e) fixing a second end of the brace to the base. A method as claimed in claim 19 including the step of f) securing the brace by inserting a peg through an aperture in the brace pin.

21. A method as claimed in any one of claims 18 to 20 including the steps of g) adding adjacent shutters by engaging complementary edge 00 O sections of each shutter so as to align the surfaces of the face Fplates of each shutter, and h) fixing the added shutters in place by repeating steps b) to f) for each added shutter, wherein steps g) and h) are repeated until the complete formwork is Serected. 00

22. A kitset for a formwork system including at least one shutter, and at least one locating pin, wherein the locating pin is configured to engage with a retainer on the shutter and with a base for the formwork, such that the shutter is held in place with respect to the base.

23. A kitset as claimed in claim 22 including a brace configured to engage with a bracing attachment on the shutter.

24. A kitset as claimed in either of claims 22 or 23 including a locating bracket which is to be fixed upon a base, wherein the locating bracket is configured to hold the shutter in place with respect to a base once the locating bracket is fixed upon the base. A shutter substantially as herein described with reference to and as illustrated by the accompanying description and drawings.

26. A locating pin substantially as herein described with reference to and as 00 illustrated by the accompanying description and drawings.

27. A method of installing a shutter for a formwork system at a desired position (C substantially as herein described with reference to and as illustrated by the accompanying description and drawings.

28. A kitset for a formwork system as herein described with reference to and N, as illustrated by the accompanying description and drawings. 00