AU2006220401A1 - A Truss System with Locator - Google Patents

Description

A Truss System with Locator Field of the Invention.

This invention is directed to a system whereby roof trusses can be erected into place in a safe manner, and the invention is also directed to devices which can enable the truss erection to be carried out.

Background Art.

It is very common to use roof trusses in a building and to which the roofing sheets can be attached usually via battens.

The roof trusses are typically manufactured off-site in a factory and transported to a building site. A crane or something similar then lifts the roof trusses into position.

The building contains vertical support walls, and the trusses are placed on top of the support walls. The support walls are typically either made of timber or blocks. If the support walls are made of timber, the walls typically comprise a vertical framework of timber studs. If the support walls are made of blocks, the uppermost course of blocks is known as the bond beam.

The trusses are delivered to site and it is necessary to lift and erect each truss to the vertical position. It is very important that the trusses are placed in exactly in the correct position. Thus, the trusses need to be spaced apart by a precise distance and also need to be positioned on top of the support walls in exactly the right place.

Thus, it is normal for a worker to be positioned on top of the walls to position each truss into the correct position. However, this creates the risk situation as there is very little protection against falling. Also, it is common for the trusses to be positioned using the crane and lifting chains, and sometimes the truss can strike the worker causing injury.

It is known to position anchors (often known as cleats) on the top of the support walls and against which the trusses will be nailed or otherwise attached. These cleats O 2 typically comprise metal plates or something similar which are either anchored in the concrete of the top wall (if blocks are used) or nailed or otherwise fastened to the Sbeam on the top wall.

It is normal for a worker to stand on the truss high above the ground whilst a crane lifts another truss into place. The truss is then temporarily nailed to the previous fixed truss with a timber batten.

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The worker then needs to manoeuvre the truss such that it is positioned against the ,I 10 cleats and then the truss is attached to the cleats in the ordinary manner (typically using fasteners). This can be quite fiddly and time-consuming.

To improve safety, there would be an advantage if it were possible to place trusses into position, and typically against the pre-positioned cleats in a more straightforward and less fiddly manner.

There would also be an advantage to provide devices which could assist in the erection of trusses in a safer manner, for instance by allowing the worker to manipulate the truss from the ground, or by allowing the trusses to be placed into the correct position (for instance against the pre-formed cleats) in a safer manner. Thus, one aspect of the present invention may comprise a system and various devices that may enable trusses to be positioned accurately in place without with a reduced requirement for workers to be positioned high above the ground.

Another aspect of the invention may comprise one or more devices that may make erection and positioning of trusses simpler.

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

3 Object of the Invention.

It is an object of the invention to provide a location device that can make positioning of trusses more straightforward and less fiddly, and particularly to a device that can assist in guiding a truss against a truss anchoring member or portion (usually a cleat), or to a device that may overcome some of the above-mentioned disadvantages or provide a useful or commercial choice.

In one form, the invention resides in a location device to assist in correct positioning of a roof truss, the location device comprising a body portion which is adapted to be positioned on a top wall on which the truss will be positioned, means to retain the body portion in place on the top wall, and guide means which can support a truss and guide the truss to the correct position.

Usually, the top wall will contain some form of truss anchoring member such as a cleat or something else, and the location device can assist in guiding the truss towards and against the cleat.

The location device is preferably reusable and it is envisaged that a pair of location devices will be required for each truss with a location device being positioned on each top wall across which the truss will span.

The location device may be made of any suitable material and it is envisaged that metal such as steel will be suitable material as this will make the location device robust and able to be reused many times. However, there may be circumstances where other materials may also be suitable such as plastics, fibreglass, laminates structures and the like.

The body portion of the location device may have a configuration to enable it to be positioned on the top wall. It is envisaged that the body portion will contain at least one, and preferably a pair of opposed sidewalls which able to extend down each side of the top wall to position the body portion on the top wall. The sidewalls may be continuous or discontinuous. For instance, it is also envisaged that the body portion will contain a pair of projections such as prongs or finger members extending down each side of the top wall to locate the body portion in place in which case a continuous side wall need not be required.

The "width" of the body portion should be sufficient to enable it to be positioned on the top wall. The body portion may have a fixed width or may have some form of adjustability to enable the width to be adjusted to different widths of the top wall. In most cases, the top wall will have a standard type width (for instance the width of block or a beam), and in these cases, a fixed width body portion may be suitable.

It is envisaged that the width of the body portion will be between 100-300 mm and typically between 100-200 mm.

If the body portion is provided with side walls, these may depend from the top wall by any suitable distance to locate the location device on the top wall. It is envisaged that the height of the sidewalls will be between 10-100 mm although it is not considered that any particular limitation should be placed on these sizes.

The body portion may comprise a top wall or an interconnecting portion which interconnects the side wall. For the sake of convenience, this will be called a "top wall". The top wall need not be continuous and therefore it is envisaged that the top wall will contain at least one and preferably more than one interconnecting member to interconnect the sidewalls thereby giving the body portion a generally U shape configuration when viewed in side elevation. This is also generally consistent with the shape of the top block or the beam on which the truss will be located.

It is also envisaged that the "width" of the body portion may be larger than the "width" of the top block or the beam and that some form of adjustment means is provided to temporarily clamp or lock the location device in place. The adjustment means may comprise a threaded rod, a locking cam, or something similar to lock the body portion temporarily in place.

In this version of the invention, the adjustment means may also comprise part or all of the means to retain the body portion in place on the top wall.

In a variation of the invention, it is envisaged that the anchor means (typically a cleat) on the top wall can be used to retain the location device in place and therefore separate clamps or fasteners need not be required.

Typically, the anchor means will project from the top wall to provide a side face or something similar against which the truss can be located and fastened. Therefore, the invention also envisages the location device having a configuration that can abut against the cleat or other anchor means, to hold the location device in place during positioning of the truss. An advantage of this arrangement is that it may be more convenient to remove the location device after use.

The location device contains a guide means which can support and guide a truss to the correct position. The correct position will typically be against the cleat or other projecting anchor means. The guide means may comprise an inclined wall having a lower end adjacent the anchor means. Thus, when a truss is placed on the guide means, it will naturally slide down the inclined wall to end up adjacent the anchor means which is the desired location.

The guide means may have a length of between 10-100 cm and will typically have a length of between 10-50 cm. This means that a truss can be lifted (typically by a crane) and lowered such that it strikes any part of the inclined guide means and the weight of the truss is usually sufficient to slide the truss down the guide means and against the cleat.

The angle of the inclined guide means may vary to suit but it is envisaged that the angle would be between 20-60' and typically about 450.

The guide means may extend above the remainder of the location device and thus generally above the top wall when the location device is positioned in place.

It is envisaged that a single guide means will be sufficient, but there may be IO 6 circumstances where a pair of guide means may be more suitable, or even more than a pair of guide means.

,I It is also envisaged that the angle of the guide means may be adjustable. Thus the guide means may be hingedly mounted adjacent one end (typically the lower end) and some form of adjustment may be provided.

For easy removal of the location device after use, it is envisaged that a locking bar

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will be provided. The locking bar may be movable between a free position where the ,I 10 location device can be removed and a locking position where the location device is held in place.

There may be an advantage to position a similar type location device with the guide means positioned to "centre" the truss when lowered onto the device. In this variation, the guide means may comprise an inclined wall which may be substantially at right angles to the other guide means. This wall be form part of the other location device, or may be a separate item which is positioned in place on the top wall to assist with the centre alignment of the trusses.

Brief Description of the Drawings.

An embodiment of the invention will be described with reference to the following drawings in which:.

Figure 1. Illustrates a location device positioned on a block.

Figure 2. Is a plan view of the location device having guided a truss into position.

Best Mode.

Referring to the drawings there is illustrated a location device 10 which can be fitted over a block 11, or other type of top wall which will ultimately support a truss/ roof beam or other member which would benefit from the locating device.

Typically, the block or top wall will contain an attached truss anchoring means which, in the particular embodiment, comprises a cleat 12.

Location device 10 has a length of between 20-50 cm and a width of typically between 100-200 mm and is made of metal. The location device contains a pair of opposed sidewalls 13, 14 which depend downwardly and against each side of the block. If desired, the spacing between the sidewalls is such that the location device is pressed over the top of the block with the sidewalls lightly clamping against the side walls of the block to prevent the location device from easily sliding. Each side wall has a width of between 10-500 mm. The sidewalls 13, 14 are interconnected by a pair of top interconnecting members 15, 16 such that the entire location device is somewhat channel shaped.

A guide means is provided which, in the particular embodiment, comprises an inclined wall 17 made of metal. The guide means has a lower end 18 and an upper end 19 and has a length of between 10-30 cm, and is inclined by about 45' The guide means is attached to each interconnecting member 15, 16 and interconnecting member 16 contains a short upstanding support wall 20 to support the inclined guide means against bowing under the weight of the truss.

The forward part of the locating device 10 contains a locking bar 21 which is hinged to one side wall and which moves between a locking position illustrated in figure 1, and a hinged away open position where the locking bar does not extend over the top of the block 11.

In use, the locating device 10 can be placed on top of the top wall and in such a manner that the cleat 12 is positioned adjacent the locking bar 21.

It is envisaged that a locating device 10 will be positioned adjacent each cleat 12 on the top wall and, as each truss will be anchored to two cleats, and a typical roof may contain between 10-50 trusses, there may be provided between 20-100 locating devices on the top wall.

A truss 22 (see figure 2) can then be lifted by a crane and roughly positioned close to the cleat and then lowered such that the bottom part of the truss strike some part of the inclined wall 17. The truss can then be lowered a little bit more and the weight of the truss will cause it to slide down the inclined wall and against the cleat. If necessary, a worker may need to slightly manoeuvre the truss.

The truss can then be temporarily locked in place, and this can be done by temporarily nailing a batten between adjacent trusses (which is quite normal), or using one or more truss clamps or truss spacers which are known.

Once all the trusses in place, the various locating devices 10 can be removed, and the trusses can be nailed or otherwise fastened to the cleats. It is also envisaged that the trusses are fastened to the cleats prior to removal of the locating device.

It is envisaged that a worker can stand on the ground and, if necessary, use a pole or something similar to manipulate the truss to make sure that the truss lands on top of the inclined wall 17. The crane operator will also be able to manoeuvre the truss relatively easily to land on top of the inclined wall 17 as it is now no longer necessary to precisely manoeuvre the truss against the relatively small cleat.

Throughout the specification and the claims (if present), unless the context requires otherwise, the term "comprise", or variations such as "comprises" or "comprising", will be understood to apply the inclusion of the stated integer or group of integers but not the exclusion of any other integer or group of integers.

Throughout the specification and claims (if present), unless the context requires otherwise, the term "substantially" or "about" will be understood to not be limited to the value for the range qualified by the terms.

Any embodiment of the invention is meant to be illustrative only and is not meant to be limiting to the invention Therefore, it should be appreciated that various other changes and modifications can be made to any embodiment described without departing from the spirit and scope of the invention.

Claims (8)

1. A location device to assist in correct positioning of a roof truss, the location device comprising a body portion which is adapted to be positioned on a top wall on which the truss will be positioned, means to retain the body portion in place on the top wall, and guide means which can support a truss and guide the truss to the correct position.

2. The device as claimed in claim 1, wherein the guide means comprises an inclined wall.

3. The device as claimed in any one of the preceding claims, comprising a pair of spaced apart sidewalls adapted to extend down each side of the top wall, and at least one interconnecting member.

4. The device as claimed in claim 3, wherein the inclined wall is supported by the at least one interconnecting member.

The device as claimed in any one of the preceding claims, including a locking bar.

6. The device as claimed in claim 5, wherein the locking bar is hingedly mounted to one side wall of the device.

7. A method of locating a truss against a truss anchor, the method comprising positioning a locating device as claimed in any one of the preceding claims adjacent the truss anchor such that the guide wall is adapted to guide a truss along the guide wall and against the truss anchor.

8. A location device substantially as hereinbefore described with reference to the illustrations.