The present invention relates to a flexible member and a method for its manufacture . The present invention more particularly relates to a flexible member suitable for use in a marker post.

Marker or delineation posts (hereinafter referred to generally as "marker posts") are used for a variety of purposes such as directing or separating traffic, delineating traffic lanes and for carrying signs and other indicia. Marker posts can be used in a number of environments , such as to delineate the edge of public roads , or to alert equipment operators to hazardous areas for example in a mining or construction site. In all these environments, marker posts are often damaged due to impact by vehicles or other objects, making it necessary to repair or replace the marker posts . Even where the marker post is constructed of a resilient or flexible material, the nature of the impact in many cases can still cause irreparable damage to the marker post such as by causing it to be bent completely over and result in plastic deformation of the post.

The present inventor has developed a flexible member for use in a marker post that overcomes , or at least alleviates , one or more of the problems discussed above.

According to the present invention , there is provided a flexible member for use in a marker post, wherein the member is substantially elastically bendable about one or more axes and includes a laminate formed by bonding together under heat and pressure an assembly of layers , including at least one layer comprising uncured, wire reinforced elastomeric

material . The elastomeric material is typically cured rubber which is curable upon application of the heat and pressure .

Accordingly, the bonding step results in curing of the at least one layer of uncured, wire reinforced rubber. The laminate may comprise a plurality of layers of uncured wire reinforced rubber . In one embodiment of the invention , at least the majority of layers comprise uncured wire

reinforced rubber.

In one embodiment, the flexible member is a flexible rubber hinge . In another embodiment, the flexible member is a flexible rubber pole .

Accordingly, the present invention also provides a flexible hinge for use in a marker post, wherein the hinge is

substantially elastically bendable about an axis and includes a laminate of two or more layers , wherein said laminate is formed by bonding together under heat and pressure an assembly of layers, including at least one layer comprising uncured, wire reinforced rubber.

The present invention further provides a flexible pole for use in a marker post wherein the pole is substantially elastically bendable and includes a laminate of two or more layers , wherein said laminate is formed by bonding together under heat and pressure an assembly of layers including at least one layer comprising uncured wire reinforced rubber .

The present invention also provides a marker post including the flexible member of the present invention .

For a given size of the flexible member, the number and thickness of the respective layers may depend on the gauge of the wire reinforcing. Where the wire reinforcing has a relatively high gauge , a fewer number of relatively thicker layers is typically used. Conversely, where a relatively low gauge wire is used, a higher number of relatively thinner layers may instead be used. The wire elastomer ratio may be varied in order to vary the elasticity of the flexible member, to suit different applications . The elasticity is typically measured by the degree of shape memory after bending.

Ά first embodiment of the marker post of the invention includes an upper body section and a resilient base for engagement with the ground and connected to the upper body section, wherein the base includes a flexible hinge which is substantially elastically bendable about an axis and includes a laminate of two or more layers , with at least one said layer comprising wire reinforced rubber, wherein said laminate is formed by bonding together an assembly of layers under heat and pressure, including at least one layer comprising uncured, wire reinforced rubber. The base of the marker post may also include an anchoring member provided at the lower end of the post .

The anchoring member may comprise a drivable spike , a surface mount or a socket mount.

Ά second embodiment of the marker post of the invention comprises a marker post including a resilient upper body section and a base for engagement with the ground and

connected to the upper body section, wherein the upper body section includes a flexible rubber post which is substantially elastically bendable about one or more axes and includes a laminate of two or more layers, with at least one layer comprising wire reinforced rubber, wherein said laminate is formed by bonding together an assembly of layers including at least one layer comprising uncured wire reinforced rubber.

The or each axis is typically transverse with respect to the marker post. The laminate is formed by bonding an assembly of layers, including at least one layer of uncured, wire reinforced rubber, together under heat and pressure. The or each wire reinforced rubber layer may comprise sublayers of wire reinforcing and uncured rubber and may comprise a sheet formed by providing a sub layer of wire reinforcing between two uncured rubber sub layers . The rubber sheets may have a Tensile strength varying between 10 and 15 MPa such as about 12 MPa. The elongation of the rubber sheets may be from 400% to 500%, such as about 450%. The hardness may vary from about 65 to 80 Shore A, such as about 68 Shore A. The density may be from about 1 to 1.5 g/cm ³ , such as about 1.2 g/cm ³ .

Lamination may be conducted in a mold having heated platens . The temperature and pressure of lamination will depend on the softening temperature of the rubber and the number of layers in the laminate. The platen temperature may be at least

140°C, such as around 150°C. The pressure of lamination may be in excess of 100 psi, such as around 150 psi.

In an embodiment of the invention, the wire reinforcing is embedded within the uncured rubber sheet. The wire

reinforcing may conveniently be provided within a mesh structure within the rubber sheet.

Two or more layers including at least one reinforced uncured rubber sheet are assembled together and bonded by application of heat and pressure in order to form the laminate . Where the wires of the wire reinforcing within each sheet are arranged parallel to each other, alternate sheets may be arranged such that the respective wires in adjacent sheets are either parallel or at an angle to each other.

In an embodiment of the invention, at least the majority of layers in the laminate comprise wire reinforced rubber. The laminate may additionally include layers of unreinforced rubber.

The number of layers in, and thereby the thickness of the laminate will depend on the application of the member. For example, where the member is a flexible hinge, the thickness of the laminate will depend on the size and weight of the body section which is supported by the hinge with the thickness of the hinge generally increasing as the size and/or weight of the body section increases .

The flexible member preferably has 75% or higher shape memory after deflection . More preferably , the flexible member has at least 90% shape memory. Accordingly, when a marker post including the flexible member is impacted by a vehicle or another object, the member is sufficiently resilient to return the marker post to approximately its original position.

The flexible member typically may have sufficient rigidity to be free standing in an upright orientation when properly supported by the anchoring member and sufficient flexibility to return to the upright orientation if deflected, for example, by contact with a vehicle or moving object. In the first embodiment of the marker post of the invention, where the flexible member is a hinge, it may be of any suitable shape, such as rectangular, cylindrical, elliptical or triangular in cross section . Preferably the flexible member is a substantially elongate planar body, which is bendable about a transverse axis. The hinge may be configured such that it is bendable about a single axis . The hinge may be mountable to an anchoring means at one end and to an upper body section at the other end thereof. The body section of the first embodiment of the marker post may typically comprise a post member comprising a light weight material . Suitable plastics materials are high density polyethylene (HDPE) , rigid polyvinyl-chloride (RPVC or UPVC) or polypropylene (PP) . Alternatively, the light weight material may comprise a sheet metal, such as aluminium. For such an application the hinge may only require 2 to 3 layers corresponding to a thickness of around 15 to 18mm, in order to provide adequate support for the post member . Where the hinge is to be used to support a sign post, the hinge may need to be thicker, and comprise a higher number of layers in order to be sufficiently strong to support the weight of the post and sign. In this application, the hinge may have a minimum of 3 layers and/or a thickness of at least 18mm.

In the case of a marker post used to identify a hazardous area in an open cut mine, the post may be around 3 metres high.

The body section would necessarily be significantly larger and therefore heavier in order to be visible, for example, from inside a mining truck. In that case, the hinge may require greater than three layers to provide sufficient support, such as up to five or even ten layers and/or be a minimum of 20mm thick, such as 40-50 mm thick, or higher.

In the second embodiment of the marker post of the invention, where the flexible member is a pole , the flexible member may be a substantially elongate body which is bendable about at least one transverse axis . The flexible pole may be generally cylindrical . The pole may be configured such that it is bendable about a number of transverse axes , such that it may bend in a number of directions . The pole may include one or more mounting zones for receiving thereon indicia such as a sign , reflectors or the like . The or each mounting zone may comprise one or more flats on the surface of the pole . The flats are preferably integrally formed during the lamination process . The pole is preferably adapted to be mounted to the ground via an anchoring means at one end. The anchoring means may comprise a socket provided in or on the ground into which the end of the pole is received and secured such as by pins , wedges or bolts . The present invention is described by way of example with reference to the accompanying drawings , in which : Figure 1 is a perspective view of a first embodiment of a flexible member (comprising a hinge) in accordance with the present invention ; Figure 2 is a sectioned view of the flexible hinge shown in Figure 1 ;

Figure 3 is a perspective view of the flexible hinge attached to an anchoring member;

Figure 4 is a perspective view of one version of a first embodiment of a marker post of the invention; and

Figure 5 is a perspective view of another version of a first embodiment of a marker post of the invention.

With reference to Figures 1 and 2 , a flexible hinge 10 is shown comprising a substantially rectangular laminate of three wire reinforced rubber sheets. The hinge 10 is elastically bendable about a transverse axis shown generally as X-X.

The laminate 10 is formed by assembling three wire reinforced rubber sheets in an uncured state and applying heat and pressure in order to bond them together . The flexible hinge 10 also includes a number of holes 12 formed into the major surfaces 14 thereof for locating mechanical fasteners, such as rivets , screws or bolts . The laminate structure of the hinge 10 is evident from the cross section shown in Figure 2, in which wire reinforced rubber layers 16 a,b,c are visible.

Figure 3 illustrates the hinge 10 connected to an anchoring member 18 comprising a drivable steel spike which is adapted to be driven into the ground. The hinge 10 and anchoring member 18 are connected together by a series of mechanical fasteners such as pins, rivets or bolts 20. The hinge 10 and anchoring member 18 together form a resilient base 22 which is suitable for supporting a marker post 24 which is described below. Figures 4 and 5 are two versions of a marker post 24 and 124 respectively . Each version includes a resilient base 22, 122 comprising a hinge 10, 110, connected to an anchoring member 18, 118. The resilient base 22,122 is connected to an upper body section 26, 126 by mechanical fasteners, in this case, bolts 28, 128. In the version shown in Figure 4, the upper body section 26 comprises a profiled rectangular roadside marker post 30 made from UPVC and adapted to carry reflectors . In the version shown in Figure 5, the upper body section 126 comprises hazard marker pole 130 constructed from plastics material. The hazard marker pole 130 is significantly larger and heavier than the roadside marker post 30, and therefore requires a hinge 110 having a relatively higher number of layers to provide sufficient strength in order to adequately support the hazard marker pole 130 in its upright position. The hazard marker pole 130 may be use in mining or construction

environments, for example to delineate the cliff edge of access roadways in an open cut mine .

With reference to Figures 6(a) and 6(b), a flexible pole 210 is shown comprising a substantially cylindrical laminate of several wire reinforced rubber sheets. The flexible pole is elastically bendable about virtually any transverse axis , a representative number of which are shown generally as X' - X' , X" - X" , X' " - X' " , and X" " - X" " . The laminate 210 is formed by assembling several wire

reinforced uncured rubber sheets in a mould and applying heat and pressure in order to cure the rubber and bond the sheets together. During the molding process, a longitudinal flat 240 is integrally molded along the length of pole 210. Mounting lugs 242, for receiving signage thereon, are attached to the flexible pole 210 by means of bands 244. The mounting lugs 242 project from the longitudinal flat 240 and include apertures 246 for receiving screws or bolts. Figure 6(b) shows sign 248 mounted to the post 210 by means of bolts 250 which are received in the apertures 246. The flexible post 210 is mounted to the ground (or other

horizontal surface) by means of a surface mount comprising mounting collar 252 including a central aperture 254 into which is received a lower portion of the flexible pole 210. The mounting collar 252 includes securing means comprising bolts 256 which are received in locating holes 258 and bolted to the underlying surface. The flexible pole 210 is retained in the socket 254 by means of securing pins 260 which are received in apertures 262 and retain the flexible pole 210 in the aperture 254 by mechanical interlocking. Figure 7 (a) and (b) illustrate an alternative version of the second embodiment of the marker post. In Figure 7, like reference numerals refer to like parts as illustrated in Figure 6. The second version of the marker post illustrated in Figure 7 differs from that illustrated in Figure 6 in that the version illustrated in Figure 7 is mounted partly in ground. In Figures 7(a) and (b) , the dashed line G represents ground level. A cylindrical socket 370 extends from below ground level to slightly above . The lower end of flexible post 310 is received into the upper end of the socket 370 and secured in place by suitable means. In this case, a securing wedge 372 is forced into the open end 374 of the socket 370 between the flat 340 and the inner surface of the socket 370 in order to retain the flexible post 310 in the socket 370. However, an alternative method would be to drill a hole in the socket (370) within the area above ground level and securing the post in place by means of a screw in post (310) . A mounting collar 352 may be used to further secure the flexible post 310 in place in the same manner as described in relation to Figure 6. The central aperture 354 extends through the collar 352 and receives the upper end of the socket 370 therein . In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word

"comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense , i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention .

Many modifications may be made to the embodiments of the present invention described above without departing from the spirit and scope of the present invention.