The invention has particular application to portable fences of the type used for the erection of temporary fencing around building and construction sites, roadworks and car parks in order to prevent unauthorised access of the general public. In many cases such sites are dangerous and access must be prevented for safety reasons.

BACKGROUND ART The presently available portable fences often seen around construction sites typically include fence panels having frames constructed of galvanised pipe and chain wire infill mounted on concrete support bases. In use, the bases rest on the ground and the stiles engage in vertical passages formed in the bases. The bases are typically rectangular in form having a length of about 600 mm, a width of about 300 mm and a height of about 150 to 200 mm with the sides tapering slightly inwards towards the top in some cases. One form of portable fencing with concrete bases is described and illustrated in Australian Patent No. 640807 to Rynenberg et al. Another example of a basic rectangular form of base is shown in Australian Patent No. 654255 to Thomas.

Australian Patent Application No. 54691/98 to Grant describes and illustrates a plastic water filled block for supporting portable fencing of elongated hexagon form which operates in much the same manner as the two previously described bases and it will be appreciated that the hexagon base still has a generally rectangular appearance. Concrete bases of the same general elongated hexagon form are also known.

One problem with the abovementioned prior art bases for temporary fencing is that they must be arranged with their long sides laterally of the fence panel in order to provide sufficient resistance to side loading. However, the rectangular bases pose a safety hazard to pedestrians moving adjacent the fence in that they can cause stumbling and falling. Furthermore, the shape of the prior art bases is such that any pedestrian who falls onto one of the bases could suffer serious injury due to the severe

corner edges. Additionally, motor vehicles which hit such bases can suffer serious tyre damage and even damage to the steering gear and in some cases the driver could even lose control of the vehicle. The rectangular bases can be used incorrectly with their long sides lengthwise of the fence and thus a relatively unstable and dangerous fence can result. Another problem with water filled prior art bases is that they typically have filling openings which require caps, and in use the caps often get lost thus leaving the water open to evaporation with a consequential loss of weight and a decreased resistance to side loading.

One object of the present invention is to provide a support base for temporary fencing which is less prone to causing stumbling than prior art bases. Another object is to provide a support base which is less likely than the prior art bases to cause injury if a pedestrian or a vehicle hits the base. Another object is to provide a base which can be used for forming junctions in a portable fence. Still another object is to provide a water filled support base which is less prone to the problems associated with water evaporation.

DISCLOSURE OF THE INVENTION With the foregoing and other objects in view this invention in one aspect resides broadly in a support base for portable fencing, the base being of hollow construction and adapted to contain a liquid to weight the base in use, the base having a substantially square lower wall and a substantially square upper wall of smaller dimensions spaced above said lower wall and coaxial therewith, and a side wall extending between said lower wall and said upper wall the angle between said side wall and said lower wall being substantially constant around the axis and one or more recessed compartments formed in the hollow and opening to said upper wall, the or each recessed compartment being adapted to receive therein and support a stile of a fence panel in a generally upright manner, and a filling opening for filling the hollow with water. Preferably the side walls are inclined to the lower wall at an angle of about 60° which is believed to be relatively safe for pedestrians and does not substantially reduce the resistance of the base to overturning moment.

Terms such as side, front, upper, lower, and the like are used for the purpose of description and illustration of the invention in the position it would normally be used in an erected fence and are not intended to limit the invention to use in any particular attitude.

Preferably, each recessed compartment is a passage formed by a tubular wall portion extending from the lower wall to the upper wall, each passage opening to both the upper and lower walls. Advantageously, such construction provides for the tubular wall portion to be supported at both ends for increased strength.

Additionally, such construction allows the ends of the stiles of the fence panel to be supported by the ground. Furthermore, pegs or stakes can be driven through a passage to secure the base to the ground if additional stability is required.

Preferably, the recessed compartments are shaped to receive either a round post or a square post and in a preferred form either a 62 mm diameter round post or a 50 mm square post. While this could be achieved by a number of differently shaped passages it is preferred that the cross-section of the passages be star- shaped with eight points on the star to accommodate the square posts being inserted either aligned with the sides of the lower and upper walls or with the diagonal of the lower and upper walls and the walls of the recessed compartments between the points of the stars being of circular section to accommodate round posts.

In a preferred form, four passages are provided symmetrically about the vertical axis of the base, the passages being arranged such that a first pair is bisected by a first plane extending diagonally across the base and the second pair is bisected by a second plane at right angles to the first plane along the other diagonal, while the filling opening is located coaxial with the axis of the base. In another form, only one recessed compartment is provided, that one being located coaxial with the axis of the base while the filling opening is offset from the axis.

Preferably, the base wall includes recesses (or indentations) opening to the side walls of a size sufficient to permit a person's fingers to be at least partly inserted under the support base while it is resting on a flat surface in order to gain sufficient purchase to lift the support base or at least

tip it over. It is also preferred that a central portion of the base wall be recessed so as to form a downward depending protrusion adjacent the perimeter of the base wall. In a preferred form the size of the recess is slightly greater than that of the upper wall but of the same shape to allow partial nesting of one base with another for transport and storage purposes.

In another aspect the invention resides broadly in a support base for portable fencing, the base being of hollow construction and adapted to contain a liquid to weight the base in use, and having a lower wall and an upper wall spaced above said lower wall and a side wall extending between said lower wall and said upper wall, and one or more recessed compartments formed in the hollow and opening to said upper wall, the or each recessed compartment being adapted to receive therein and support a stile of a fence panel in a generally upright manner, and a filling opening in the upper wall for filling the hollow with water, the hollow being divided into a main storage chamber and a well by an internal wall, the well being located beneath the filling opening and communicating with the main storage chamber via a passage between the internal wall and the upper wall or near the upper end of the internal wall so that liquid entering the hollow through the filling opening first fills the well and then flows into the main storage chamber. Preferably, a tube, for example, formed by a skirt, depends from the upper wall about the opening and terminates in the well below the passage between the well and the main storage chamber to provide an annular passage between the internal wall and the skirt. Advantageously, this arrangement limits the surface area of liquid in the base exposed directly to atmosphere and furthermore provides a tortuous path for vapour flow from the main storage chamber to the filling opening and thus inhibits evaporation to an extent whereby the filling opening does not normally need to be closed for long periods of use. In such form, the upper wall may also include one or more breather holes to allow air to escape from the well and the main storage chamber as the base is being filled with liquid.

Preferably, such breather hole or holes pass through the upper wall directly above the internal wall so that liquid in the main

storage chamber is not exposed directly to atmosphere.

Preferably, the lower wall is substantially the same shape as the upper wall but of smaller dimensions.

In yet another aspect, the invention resides broadly in a support base for portable fencing, the base being of hollow construction and adapted to contain a liquid to weight the base in use, the base having a substantially square lower wall and a substantially square upper wall of smaller dimensions spaced above said lower wall and a side wall extending between said lower wall and said upper wall and coaxial therewith, the angle between said side wall and said lower wall being substantially constant around the axis and one or more recessed compartments formed in the hollow and opening to said upper wall, the or each recessed compartment being adapted to receive therein and support a stile of a fence panel in a generally upright manner, and a filling opening for filling the hollow with water, the hollow being divided into a main storage chamber and a well by an internal wall, the well being located beneath the filling opening and communicating with the main storage chamber via a passage between the internal wall and the upper wall or near the upper end of the internal wall so that liquid entering the hollow through the filling opening first fills the well and then flows into the main storage chamber, and a vent opening in said upper wall, said vent opening being in fluid communication with the lower portion of said hollow via a tube portion depending from said upper wall about said vent opening and terminating near to but spaced from said lower wall.

In all forms of the invention it is preferred that the upper wall be slightly concave so that rain water may drain towards the filling opening to replenish the liquid in the well or the storage chamber. It is also preferred that a plurality of flutes be provided in the upper wall running thereacross and terminating at the filling opening. Advantageously, the flutes form guides to direct inflowing rain to the filling opening and also the internal ribs formed by the flutes direct outflowing liquid to the opening when the base is inverted to assist with emptying as well as increasing the strength of the upper wall.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that this invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings wherein: Fig. 1 is a pictorial representation of a temporary fence utilising prior art support bases; Fig. 2 is a perspective view of a support base according to the invention; Fig. 3 is a plan view of the support base of Fig. 2; Fig. 4 is a perspective cut away view of the support base of Fig. 2 from underneath; Fig. 5 is a perspective view of another support base according to the invention; Fig. 6 is a cross sectional view of the support base of Fig. 5 along line 5-5; Fig. 7 is a diagrammatic cross-sectional view of the opening of the post mounting tubes of the support base of Fig. 2; and Fig. 8 is a diagrammatic cross-sectional view of the opening of an alternative post mounting tube; DETAILED DESCRIPTION OF THE DRAWINGS The support base 110 illustrated in Fig. 2 is constructed of a plastics material and takes the shape of a truncated square pyramid with rounded corners and has a rounded square lower wall 111 with a side length of 610 mm, and a rounded square upper wall 112 spaced from the lower wall and co-axial therewith, the upper wall and the lower wall being joined by a sloping side wall 113 making an included angle of 60° with the lower wall, the upper and lower walls being spaced from one another to give an outside vertical dimension of 150 mm. The thicknesses of the lower wall, upper wall and side wall as well as that of the tubes is selected to form a suitably strong and durable support base and is typically between 3mm and 5mm. The lower wall, the upper wall and the side wall together define a hollow or chamber 114 adapted to contain water for weighting the support base. A support base of these dimensions will have a gross mass of about 39kg when filled with water. The density of the walls is approximately the same as water and changes in wall thickness will have very little effect on the gross mass. The support base of these dimensions

is intended for use with a chainwire fence 1800mm high and should withstand windloads created by a windspeed up to 75km per hour provided that the water level is maintained such that the gross mass is greater than 32kg. Of course, if greater windloads are encountered, then a bracing system may be utilised.

Four post mounting tubes 115,116,117 and 118 extend vertically through the chamber opening to the upper wall and the lower wall and are adapted to receive therein the galvanised pipe stiles 21 of fence panels of the type shown as item 20 in Fig.

1, while a filling opening 122 is provided in the centre of the upper wall in a slightly dished region. The mounting tubes are located astride respective vertical planes extending between the opposite corners of the support base and each has a star-shaped cross-section which will be described later.

It will be seen that in use the post mounting tubes can be used to accommodate up to four stiles so that the support base can be used to create a Tee or cross intersection of fence panels as well as an in-line temporary fence. Also, the four tubes allow some length variation and position variation for the erection of an in-line temporary fence. Moreover, if two of the tubes are used for supporting fence panels, a third can be used for supporting a flagpost, a sign post or similar warning or advertising device.

The sloping side wall 113 is constituted mainly by two pairs of two opposed side wall portions 113a, b, c and d joined at their respective adjacent ends by four rounded corner portions 125, with both the corner portions and the wall portions meeting the upper wall at a rounded upper edge portion 120. At its lower edge the sloping side wall 113 meets the lower wall via a vertical portion 126.

Four flutes shown typically at 136 are provided along the bisecting lines of the upper wall, each flute extending from the rounded upper edge portion to the filling opening 122 which has a bevelled upper edge where it opens to the top of the upper wall.

A recess 132 is provided in the lower wall in the form of a rounded square slightly larger in side dimension than the upper wall 112 to permit partial nesting of the support bases for

transport and storage. The base wall 13b about the recess 132 provides a flat annular foot portion for the support base and a finger slot shown typically at 130 extends from each of the four sides into the foot portion.

A cup-like well 135 is provided inside the chamber 114, immediately below the filling opening and a tubular skirt 129 depends from the upper wall about the filling opening and terminates within the well. As can be more clearly seen in Fig.

4 the well is integrally moulded with the base wall and has an inner wall 137 and an outer wall 138, both of tapering circular cross-section, the outer wall tapering inwardly and the inner wall tapering outwardly in the upward direction, to terminate in an annular lip 134 defining the opening in the well. The lip is higher than the free lower end of the skirt so that it forms a weir over which water flows when the chamber 114 is being filled with water. Breather holes 121 are provided in the upper wall to allow air to escape from the chamber as the support base is being filled with liquid.

Referring to Fig. 7, the internal shape of the cross-section of the mounting tubes permits either a circular tube or square tube to be inserted. Each tube has eight circular portions shown typically at 151 interposed between four orthogonal and four diagonal channels seen as indentations in the cross sectional view which are provided alternately and at evenly spaced intervals about the tube circumference, and given reference numerals 154 and 152 respectively. The channels may be referred to as"star-points"in the star-like cross-section and permit a square section stile to be mounted with its flat sides either at 90° or at 45° to the diagonal bisecting planes through the support base 110, but also permit a circular section stile to be inserted mounted instead.

In the alternative cross-section 155 shown in Fig. 8, the tube wall has a circular portion 157 and a square portion 158, the square portion being arranged so that the full side 159 is located a distance from the opposite side of the circular section substantially equal to the length of the full side 159. This arrangement permits either square or round section stiles to be mounted but restricts the square section stiles to one

orientation.

The improved support base 210 shown in Fig. 5, is the same as that of Fig. 2 in many respects and for the sake of brevity corresponding reference numbers will be used for corresponding parts but with the prefix numeral"1"replaced by a"2". Support base 210 includes five post mounting tubes, four (215 to 218) of which are in the same positions as in support base 110 while the fifth (209) is centred on the vertical axis of the base.

Advantageously this allows the support base to be used for one centrally located post if desired.

Support base 210 also includes a vent opening 241 in the upper wall 212 spaced from the filling opening 222. A tubular skirt 242 depends from the upper wall about the vent opening and terminates near to but spaced from the base wall 211. The tubular skirt provides a vent for the hollow 214 when the support base is inverted thereby allowing quicker emptying through the filling opening. The filling opening and the vent opening are each located in spaced apart recesses 243 and 244 which open to the opposite side walls 213a and 213c thereby allowing water to flow out and air to flow in when the support base is inverted and resting on a flat surface.

Two flutes 236 extend from each of the outer four post mounting tubes to the top centre of the nearest adjacent side walls thus creating an internal rib across each of the largest sections of the upper wall, the flutes terminating at two sides in the respective recesses 243 and 244. It will be seen that this support base has a deep second recess 246 formed in the base wall concentric with recess 232. Advantageously the vertical wall forming this recess increases the strength of the base wall and also provides extra space so that the fence stiles protruding downwardly from the post mounting tubes can easily have pins fitted thereto to prevent them being removed from the support base when in the normal in-use position. This improvement can also be incorporated into the support base 110 if desired.

In use, the support base 210 may be utilised in constructing a temporary fence with the flat side portions preferably arranged at 45° to the alignment of the fence. The base supports are filled with water preferably prior to the insertion of the stiles

of the fence panels into the passages. Where a straight fence is required, the stiles are placed in the diagonally opposed passages in line with the fence. Alternatively, the alternative diagonally opposed passages may be used to provide a saw-tooth or square form of fence when viewed from above. Tee intersections and crossing intersections may be accommodated buy using one or two of the other passages respectively as required. In order to dismantle a temporary fence, the fence panels would be removed first and then the support bases would be tipped over to allow the water to drain from the hollow via the filling opening. Once drained, the support bases may be stacked on top of one another in either the upright or the inverted attitude on a truck.

Support bases constructed according to the present invention can be used to support corner posts for other applications, such as, for example, for soccer fields and the like, or flags for slalom, racing or equestrian events and safety bollards.

It will be appreciated that the prior art support bases shown typically as item 19 in Fig. 1 create undesirably dangerous obstacles to pedestrians, strollers and vehicles. The present invention lessens the likelihood of accidental injury to pedestrians, children in strollers and persons in vehicles because of the upwardly sloping nature of the wall 213 and the generally rounded corners of the support base. Furthermore, the invention reduces the burden for loading and unloading support bases which previously have been constructed of concrete and furthermore the support bases provide for more stable temporary fences.

It is to be understood that the foregoing description has been given by way of illustrative example of the invention and all modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as defined in the appended claims.