Field of the Invention

The present invention relates broadly to builder's hurdles. Builder's hurdles are used in the construction industry for example to mark out footings for a building or to indicate the profile of ground being prepared for road construction.

Background of the Invention

Builder's hurdles arc used in conjunction with stringlines to mark out building foundations or floor plans. Conventionally, builder's hurdles have consisted of two pieces of timber driven into the ground and an additional piece of timber (the cross member) nailed on top of the two pieces of timber in the ground. Nails are hammered into the cross member to serve as guides and for the attachment of the stringlines. This on-site fashioning of hurdles is wasteful of time and materials - the hurdles are usually discarded after use and a new set fashioned for the next project - and the rough and ready approach to their fashioning and their positioning is not conducive to accurate marking put.

The present invention provides an improved builder's hurdle that avoids at least some of these problems and is a simple, easy to use and readiJy reusable piece of equipment.

Summary of the Invention

The present invention provides a cross member of a builder's hurdle comprising a first elongate member and a second elongate member, wherein the first elongate member includes at least one movable pin and a mounting means; and the second elongate member includes a mounting means; and wherein the second elongate member is slidably engageable with the first elongate member.

In certain embodiments of the present invention the first elongate member includes a plurality of movable pins. Optionally, the first elongate member includes a plurality of markings to facilitate positioning of the movable pin or pins thereon. Brief Description of the Figures

Figure 1 shows various views of an embodiment of a cross member of a builder's hurdle according to the present invention. Views from above (A, E), side (B, F), beneath (C, G) and in cross section (D, H) are shown. The cross member is shown in either the fully open condition (A-D and T) or the closed condition (E-G). Also shown are perspective views (I, J) and an exploded view (J) showing various components of this embodiment of the invention.

Figure 2 shows various views of a further embodiment of a cross member of a builder's hurdle according to the present invention. Views from above (A), side (B, C) and in cross section (D, E) are shown. The cross member is shown in either an open condition (C) or the closed condition (A, B, D). Also shown is an exploded view (F) of this embodiment of the invention showing various components.

Figure 3 shows a cross section of an alternative embodiment of the present invention.

Detailed Description of the Invention

The present invention relates broadly to builder's hurdles. Builder's hurdles generally consist of two pieces of timber driven into the ground and an additional piece of timber (generally referred to as the cross member) nailed on top of or near the top of the two pieces of timber in the ground (the legs). Nails arc then hammered into the cross member to serve as pins for the attachment of stringlines. The present invention provides a cross member for a builder's hurdle which is variable in length and has one or more repositionable pin(s), to which stringlines may be attached to facilitate in accurately setting out a building. To make the present invention easy to carry or to pack, the cross member and legs caα be separate, or the three parts may be foldable relative to each other. The equipment is fully adjustable in that the legs could be made available in different lengths or even be telescopic.

An exemplary cross member for a builder's hurdle, according to the present invention, may be an easy to use, cheap, effective, time saving and readily reusable piece of equipment. It is envisaged that the cross member for a builder's hurdle of the present invention will replace the wooden hurdles to which the striπglines have been traditionally nailed to roaxk out building foundations or floor plans.

Referring to all the Figures wherein like reference numerals designate like or corresponding parts throughout the several views. The Figures show exemplary embodiments of the present invention, it is to be understood that these embodiments are not intended to limit the present invention. The skilled addressee will readily recognize alternative embodiments that may be used to put the present invention into practice, such embodiments are equally disclosed and encompassed by the present specification.

A cross member for a builder's hurdle 100 according to the present invention includes a first elongate member 110 and a second elongate member 120, wherein the first and second elongate members 110,120 are slidably engageable with each other and may be moved between a closed (Figures IE-H, 2A, 2B and 2D) and a fully open condition (Figures IA-D, II and 2C) whereby the cross member 100 is of variable length. In some embodiments of the present invention, the slϊdable engagement may be considered to be telescopic in nature. In certain embodiments of the present invention, the cross member may have a length, when in the fully open condition, of about 1000mm, 900mm, SOOmm, 700mm, 600mm or 500mm, or any length therebetween. When in a closed condition, the cross member will be somewhat shorter than the fully open cross member. Accordingly, when in a closed condition, the cross member will be approximately 700mm, 650mm, 600mm, 550mm, 5Q0mm, 450mm, 400mm or any length therebetween.

While the accompanying Figures show that the first elongate member 110 is substantially hollow and that the second elongate member 120 may be received within the first elongate member 110, the present invention is not to be limited to such embodiments. In particular, it is envisaged that alternative arrangements may also be employed. For example, as illustrated in the cross sectional view shown in Figure 3, one of the elongate members 210 may be only partly enclosed within the other elongate member 220 and retained in place by flanges 212,214.

In addition to the illustrated square and substantially open cross sections illustrated in the Figures, it is envisaged that the elongate members 110,120 may independently have any shape cross section, so long as the cross sectional shape of the two elongate members 110,120 is sufficiently complementary such that they may slidably engage to provide a cross member of variable length. Accordingly, the cross section of each or both of the elongate members 110,120 may be, but not limited to, square, rectangular, substantially open or circular.

In order to maintain the cross member 100 to a particular length, there may be provided a securing means 130. The securing means 130 may be used to fix the position of the two elongate members 110,120 relative to each other. Exemplary securing means include, but are not limited to a fastener such as a screw. In the embodiments illustrated in Figures 1 and 2, the cross member will be infinitely variable in length between the closed and fully open positions. In some embodiments of the present invention, the securing means 130 may pass through the first elongate member 110 and includes a threaded portion 132 that allows the securing means 130 to be rotated and bring a securing end 134 into contact with the second elongate member 120 thereby inhibiting movement of the second elongate member 120 relative to the first elongate member 110. Other means by which the position of the two elongate members 110,120 relative to each other may be fixed will be apparent to the skilled addressee. In such embodiments of the present invention, the cross member 100 may not be infinitely variable in length between the closed and fully open positions as such arrangements may be restricted to a number of specific lengths depending on the nature and positioning of the securing means. However, the cross member will still be of variable length.

In the embodiment of the present invention illustrated in Figure 1 , the second elongate member 120 is slidably cngageable within the first elongate member 110. At an inner end of the first elongate member is a plug member 115, through which the securing means 130 passes. The second elongate member 120 enters the first elongate member 110 through the plug member 115. At an inner end of the second elongate member 120 is a stop means 190. The stop means 190 prevents the second elongate member 120 from being readily withdrawn from the first elongate member 110 by abutting against the plug member 115, as illustrated in Figure 1D. In one example of the embodiment illustrated in Figure 1, the overall length of the cross member 100, measured between holes 182 in the mounting means may be between about 600mm in the fully open condition, and 450mm in the closed condition.

In the embodiment of the present invention illustrated in Figure 2, the second elongate member 120 is slidably engageablc within the first elongate member 110. The securing means 130 passes through the first elongate member 110 as described above. In this embodiment, there is no stop means 190 or plug member 115. In a further embodiment, the second elongate member could be provided with recesses or holes with which the securing end 134 of the securing means 130 could engage in order to prevent movement of the first and second elongate members 110,120 relative to each other. In this embodiment the cross member 100 may be restricted to a number of specific lengths depending on the nature and positioning of the holes or recesses.

A cross member according to the present invention may optionally be provided with a level determining means, such as, but not limited to, a sphit level. The incorporation of a level determining means may assist the operator to position the cross member correctly, as determined by the building site.

in order to accommodate stringlincs, a cross member of the present invention includes at least two pins 140 to which the strϊnglines may be attached. In certain embodiments of the present invention one of the pins 140 may be fixed to either elongate member 110,120 and another pin 140 may be movable along either elongate member 110,120. In other embodiments of the present invention, all of the pins 140 may be movable along one or both of the elongate members. In the illustrated embodiments, two pins 140 are shown wherein they are both movable along the first elongate member 110. It is envisaged that the pins 140 may be positioned on only one of, or on both of, the elongate members 110,120.

Iti certain embodiments of the present invention the pins 140 may be provided with a head region 142 which includes a Jip region 144 that is slightly larger than the remainder of the pin. The Hp region 144 is intended to prevent the stringlitics being accidcntly slipping off or otherwise being removed from the pins 140.

Each pin 140 may be attached to a sleeve member 150. The sleeve member 150 is intended to substantially surround an elongate member 110,120 and permits the pϊn to be moved therealong. In certain embodiments of the present invention, a pin 140 and a sleeve 150 may be co-formed as illustrated in the accompanying Figures. While the pins 140 may be movable, it is necessary to be able to fix them to a particular position along the elongate member or members 110,120. Accordingly, there may be provided fixing means 152 which may be used to prevent oτ impede movement of the sleeve 150 and thus the pin 140 along the elongate members 110,120 once the sleeve 150 and pin 140 have been moved to the desired position.

In Older to facilitate accurate and consistent positioning of the pins 140, some embodiments of the present invention may include markings 170 on one or both of the elongate members 110,120, The markings 170 may be present on the elongate member or members 110,120 along which the pin or pins 140 can be moved. Ia some embodiments of the present invention the markings 170 may be evenly spaced at distances, for example, for countries using a metric measuring system the markings 170 may be at intervals of 5mm, 10mm, 15mm or 20mm, or any length therebetween. Alternatively, for countries using an imperial measuring system the markings 170 may be at 1/4" , 1/2" , 3/4" " or 1" intervals, or any length therebetween. In yet further embodiments of the invention, there may be markings 170 in both metric and imperial spacings. Depending on the construction material of the elongate members 110,120, any markings 170 may be moulded onto, or moulded or etched into, the elongatemember 110,120.

The cross member for a builder's hurdle 100 according to the present invention may further include legs, removable legs or mounting means 180 to allow the cross member 100 Io be positioned on legs. In these embodiments of the present invention the legs are intended Io be driven into the ground. The adjustable length of the cross member 100, permits the user to drive the legs into the ground and then adjust the length of the cross member 100 to fit onto the legs via, for example, mounting means 180. In embodiments which include mounting means, there may also be provided a hole 182 through the mounting means 180 to permit a nail or screw 184 or similar to be used to secure the cross member 100 to the legs. Alternatively, where the cross member for a builder's hurdle 100 is to be used against a surface such as a wall or a fence, the cross member 100 may be fixed to that surface using, for example, nails and/or screws, or any other suitable fastening means as determined by the nature of the surface, which pass through the holes 182.

It is envisaged that the legs αpon which the cross member may be positioned will be constructed of timber, metal or plastic. Metal legs may provide the strongest and sturdiest option for legs.

It is intended that the cross member for a builder's hurdle 100 be constructed of a material that is strong and able to withstand being outside in the weather. Accordingly, the cross member 100 should be able to withstand heat, exposure to ultraviolet light, cold and water, as would be expected on a building site. Also, the cross member should be sufficiently strong so that it can be used many times without breaking or becoming damaged. With these requirements in mind, the cross member may be made of a metal such as steel, or for a lighter product, aluminium. Alternatively, the cross member may be made of a sufficiently strong and robust plastic. Suitable plastics for construction include, but are not limited to: glass-filled polypropylene, HD polyethylene or nylon. Tn further embodiments, it is envisaged that the various components of the cross member may be made of different materials.

Where the terms "comprise", "'comprises", "comprised" or "comprising" are used in this specification, they are to be interpreted as spetifying the presence of the stated features, integers, steps or components referred to, but not to preclude the presence or addition of one or more other feature, integer, step, component or group thereof. further, any prior art reference or statement provided in the specification is not to be taken as an admission that such art constitutes, or is to be understood as constituting, part of the common general knowledge.