This invention relates to an improved barrier structure.

The invention is applicable to forming fences, balustrades or the like.

In the specification of my patent application PCT/AU90/00448, there is disclosed a barrier structure comprising: barrier means including upper and lower engaging parts; elongate support members having engaging portions adapted to receive said engaging parts, respectively; and cap means adapted to fit on said support members so as to secure said upper engaging parts to their respective engaging portions.

In accordance with the present invention, there is provided a barrier structure comprising: barrier means including upper and lower engaging parts; and elongate support posts having engaging portions adapted to receive respective engaging parts, wherein the engaging portions are formed so as, during assembly of the barrier structure, to enable the engaging parts to enter the upper engaging portions, after which the barrier means is movable into downwardly extending slots of the portions to thereby engage with the support posts.

In another aspect, there is provided a barrier structure comprising: barrier means including upper and lower engaging parts elongate support posts having upper and lower engaging portions adapted to receive respective engaging parts; and a retaining member which is arranged to fit inside an upper end of a respective elongate support post to, in use, engage an upper part of the barrier means which is located in a respective. engaging portion whereby to secure said upper engaging part in the respective support post.

Preferably, a base reinforcing member is provided to secure the respective elongate support posts to a surface, the reinforcing member being arranged to fit inside the lower end of the respective elongate support post and having anchoring means for securing the reinforcing member to the surface and securing means for securely attaching the respective support post to the reinforcing member.

Preferably, each engaging portion for receiving a respective part comprises a slot, spaced from a respective end of the elongate support member, and wherein each slot has a vertical portion in which the respective part is, in use, located and a horizontal portion communicating with an upper end of said vertical portion so as to provide access for the respective part into the vertical portion from a side of the post.

En another aspect, there is provided a barrier means for use in the above described barrier structure comprising an elongate member to which the engaging parts are attached, said elongate member having a lengthwise extending cavity open to the exterior of the member via a relatively narrow lengthwise slot, said cavity being adapted to receive respective end portions of tubular elements which extend through said slot in a direction away from the member, and a spacer which is positioned in the cavity between the elements to maintain the elements in a spaced apart relationship.

In another aspect, there is provided a barrier means for use in forming a barrier structure, comprising two generally parallel elongate members interconnected by a connecting element, the barrier means having engaging parts to enable it to be connected to a post so that the members extend at upper and lower relative positions away from a post, the connecting element being coupled to the members by joints permitting lengthwise movement of the members, one relative to the other.

The present invention is described, by way of example only, with reference to the accompanying drawings wherein:

Figure 1 is a front view of one form of the barrier structure of patent application PCT/AU90/00448; Figure 2 is a perspective view of the barrier structure of Figure 1 illustrating how the barrier structure is erected;

Figure 3 is a side view of a rail of the structure of Figure 2;

Figure 4 is a side cross-sectional view of the top end of a post of the structure of Figure 1; Figure 5 is a side cross-sectional view of the top end of a post of the structure of Figure 1;

Figure 6 is a side view of the top end of the post of Figure 5 with a cap fitted thereto;

Figure 7 is a front partial cross-sectional view of the top end of a post; Figure 8 is a perspective view of a nylon feirule of the structure of Figure l;

Figure 9 is a cross sectional view of the ferrule of Figure 8 attached to a bar of the structure;

Figure 10 is a partial perspective view of another embodiment of a barrier structure according to PCT/AU90/00448;

Figure 11 is a partial perspective view of a further embodiment of a barrier structure according to PCT/AU90/00449;

Figure 12 is a partial perspective view of a still further embodiment of a barrier structure according to PCT/AU90/00448; Figure 13 is a perspective view of a barrier means in accordance with the present invention;

Figure 14 is a cross-sectional view of an upper horizontal member of the barrier means shown in Figure 13, showing the manner of interconnection therewith of an upright element of the barrier means; Figure 15 is a cross-sectional view like Figure 14, but showin a modification thereof;

Figure 16 is a cross-sectional view on the line 16-16 in Figure 14;

Figure 17 is a cross-sectional view of a spacer located within the member illustrated particularly in Figure 14, taken on the line 17-17 in Figure 16;

Figure 18 is a perspective view of an engaging part shown in Figure 13; Figure 19 is a perspective view of an alternative engaging part and a respective engaging portion of a post used in the present invention;

Figures 20 to 22 show steps in the assembly of the barrier means of Figure 13 to a post;

Figure 23 is a cross-section on the line 23-23 in Figure 22; Figure 24 is a perspective view of a spacer used in the construction of Figure 13;

Figure 25 is a cross-sectional view of a connector of the present invention; Figure 26 is a perspective cut-away view of a barrier means of the present invention;

Figure 27 is a side view of an engaging part; Figure 28 is a view of a barrier struction of the present invention;

Figure 29 is a perspective view of a plate from which a base reinforcing member is formed;

Figure 30 is a perspective view of a base reinforcing member in accordance with the present invention; Figure 31 is a perspective view of the base reinforcing member of Figure

30 position in a base;

Figure 32 is a cross-sectional view of the base and base reinforcing member of Figure 32 in use;

Figure 33 is a plan view of a plate from which an end reinforcing member is formed;

Figure 34 is a perspective view of an end reinforcing member; Figure 35 is a cross-sectional view showing the end reinforcing of Figure 34 is use;

Figure 36 is a perspective view of a modified support post ; Figure 37 is a perspective view of another modified support post; and

Figure 38 is a cross-section view of the support post of Figure 37, illustrating the manner in which a barrier means is attached thereto.

A barrier structure 2, as described in patent applications PCT/AU90/00448 is shown in Figure 1. It includes a number of rails 4 which are supported by a series of posts 6. The posts have caps 8 fitted over the top ends thereof and stand in respective bases 10. The bases 10 sit on a floor structure 12, which may comprise a verandah, balcony or merely the ground. The rails 4 include a plurality of vertical bars 14 and two upper horizontal bars 16 and 18 and two lower horizontal bars 20 and 22.

The second upper and lower bars 18 and 22 are slightly longer and protrude past the ends of the first upper and lower bars 16 and 20, as shown in Figure 2, and include disc-shaped knobs, 24 and 26 respectively disposed on the ends thereof. The knobs 24 and 26 are adapted to be received by respective slots 30 and 32 disposed in the sides of the posts 6 at each end thereof.

The posts 6 are elongate hollow tubes having a rectangular cross-section. The slots 30 disposed at the upper end 34 of the posts 6, as best illustrated in Figures 2, 5 and 7, include a horizontal slot portion 36 which is provided in the respective side 38 of the post 6 and a vertical slot portion 40 which is provided in the front of the post 6. The vertical slot portion 40 is configured to enable a knob 24 of the upper bar 18 to be passed therethrough so that the knob 24 is then disposed in the post 6 and part of the upper bar 18 rests in the vertical slot portion 36 at the end thereof, as shown in Figure 5. The knobs 24 prevent the upper bars 18 from being removed laterally from the post 6.

To secure the ends of the bars 18 fully and prevent them being removed via the vertical slot portion 40 a cap 8, as shown in Figures 2 and 6, is inserted over the upper end 34 of the post 6 so as to cover the vertical slot portion 40. The cap 8 includes vertical slots 42 disposed in the sides thereof which extend to the lower ends of the caps 8. The slots 42 are adapted to receive the upper bars 18 and act to ensure the bars 18 remain at the end of the slot portion 36, as shown in Figure 6. The cap 8 may be further secured to the top end 34 of the post 6 by a bolt, or screw, 35.

The slots 32 disposed at the lower ends 50 of the posts 6 are vertical slots which extend to the bottom of the posts 6 and are disposed on each side of a post 6.

The slots 32 are configured to receive the ends of the lower bars 22 so that the knobs

26 are disposed in the posts 6 and thereby prevent the bars 22 being laterally removed from the posts 6.

The ends of the lower bars 22 are fully secured when the lower ends 50 of the posts are placed in the respective bases 10. A base 10 is configured so as to include a recess 52, as shown in Figures 2 and 4, adapted to receive the lower end 50 of a post 6. The depth of the recess 52 is chosen so that the ends of the bars 22 are secured in a position at the ends of the slots 32 by the top 54 of the base 10, as shown in Figure 4. The engagement of the ends of a lower bar 22 in the posts 6 after insertion in respective bases 10 is such that the rail 4 can be pivoted about the axis 60 of the lower bar 22, as shown in Figure 3. The lower ends 50 may, of course, be

inserted directly into the earth at a depth which is sufficient to secure the bars 22 in the slots 32.

The knobs 24, 26 may be integral with the respective bars 18, 22 or preferably they comprise nylon ferrules 24, 26, as shown in Figure 8, which may be inserted over the ends of the bars 18, 22, as shown in Figure 9. The ferrules 24, 26 are then attached to bars 18, 22 by either welding the ferrules 24, 26 thereto, or flattening the ends 19 of the bars 18, 22, as specifically shown in Figure 9, so as to prevent the bars 18, 22 being withdrawn through the ferrules 24, 26. The attachment prevents the rails 4 -being removed from the posts 6 when a reasonable force is exerted on the rails 4, such as from a person inadvertently running into the structure 2.

To erect the barrier structure 2 the ends of the lower bar 22 are first inserted in the respective slots 32 of two posts 6, as shown in Figure 2, and the posts 6 then inserted into the respective bases 10. The lower ends 50 of the posts 6 may be fixed to the bases 10 by means of an appropriate bolt 70 or screw and the bases 10 may be secured to the chosen floor structure 12 by means of anchor bolts 72. Once the lower bar 22 has been attached and the lower ends 50 secured the rail 4 may be pivoted, as shown in Figure 2, about the axis 60 of the bar 22 so as to cause the ends of the upper bar 18 and their respective knobs 24, to be received by the upper slots 30 of the posts 6. Once received the caps 8 are then placed over the upper ends 34 of the posts 6 and erection of the structure 2 is complete.

If two rails 4 are to be attached to one post 6 then the rails 4 should be erected simultaneously.

The length of the first upper and lower bars 16 and 20 are chosen so their respective ends lie adjacent the caps 8 and posts 6 when the structure 2 is erected, as shown in Figure 1.

From the above, it will be apparent the barrier structure 2 is relatively easy to assemble and requires a minimum of connecting bolts and screws. The structure 2 is

also aesthetically pleasing as most of the connecting parts are not visible once the structure 2 is assembled, as shown in Figure 1.

In the case where the base 10 and the cap 8 are formed of, for example, plastic it may be desirable, for added security, to provide reinforcing members to secure the rails 4 in the posts 6 and to secure the posts themselves to a more structurally sound surface, such as a concrete slab. For this purpose, there is provided a base reinforcing member 150 and an end reinforcing member 151, as shown in Figures 29 to 36.

Member 150 is formed from a metal plate 152 which has four side tabs arranged about a central base section 153. Two of the tabs 157 have bar receiving slots 155 cut thereinto and the other two tabs 159 have screw holes 156 formed therein. A central hole is provided in the base section 153, through which a securing bolt, in use, passes. The tabs are bent about the central base section 153 to form an open-ended box like structure, arranged so that tabs 157 face each other, as do tabs 159. Member 150 is arranged in the base 10 as shown in Figure 31 and is securely fastened thereto, or to an underlying concrete base, upon which the base 10 rests by means of a bolt 160.

Once arranged in this manner, the posts 6 with the knobs 26 already positioned in respective slots 32 may be inserted into the base 10, similar to the manner illustrated in Figure 2, so that the knobs 26 and respective bars 22 engage respective bar receiving slots 155 of the member 150, as shown in Figure 32. Once positioned in this manner, the post 6 is securely fastened to the base 10 and the member 150 by means of a screw or bolt which passes through the screw holes 106 formed in the tabs 159 of the member 150 and corresponding holes in the base.

The retaining member 151 is shaped from an elongate plate 170 which has slots 161 cut in opposite ends 162, 163 thereof. The ends 162 and 163 are bent at right angles to the plate 170 so that the member 151 is generally U-

shaped, as shown in Figure 34. Once the barrier 2 has been constructed, but before the caps 8 are placed on top of the posts 6, the member 151 is positioned in the top end of the post 6 so that the knobs 24 and upper bars 18 engage in the slots 161, as shown in Figure 35. The member 151 arranged in this manner, reduces the likelihood of knobs 24 pivoting out of slot 30 in the case that the cap 8 is broken. The member 151 can also be secured in position by any suitable means, such as by bolting or screwing it to the post 6.

As an alternative to the method of construction used in the formation of the above mentioned barrier 2, the posts 6 may instead be fastened in position before the rails 4 are fitted thereto. A modified post 180, as shown in Figure 36 is provided for this purpose.

The post 180 is similar to the post 6 described above and like parts will be denoted by like reference numerals. The difference between the two posts is that slot 32 is replaced by an L shaped slot 181 which has a horizontally extending portion 182, which communicates with a vertical portion 183. The vertical portion 183 serves the same purpose as slot 32 of the original post 6 in that knob 26 of the rail 4 is located therein. Access to the vertical portion 183 is obtained through the horizontal portion 182. A suitably shaped sleeve 184 may also be provided which is slid over the post 180 to cover the slot 183 when the rail 4 is attached to the post 182.

Another modified post 185 is shown in Figure 37. This post has identical upper and lower slots 186 and 187 spaced from respective ends of the post. The slots each have a knob receiving opening 188, a horizontal portion 189 and a vertical portion 190 which communicates with the horizontal portion 189. To fit the rail 4 to the post, the knobs 24 and 26 are simultaneously inserted in respective openings 188 so that the associated bars 18 and 22 can pass through the horizontal portions 189 and be dropped into the vertical portions 190. In this manner, the knobs and associated ends of the upper and lower bars 18 and 22 are securely located in respective lower ends 191 of the slots. Since the knobs 24 are prevented

from pivoting out of the respective slots when the rail 4 is fixed to the post in this manner, the additional end member 151 need not be fitted.

The manner in which the rail 4 is fitted to the post 185 is shown in Figure 38. As will be appreciated, in the case where the post is firmly positioned in a ground surface, the knobs 24, 26 of the rail 4 may not be required, and the ends of the bars 18, 22, located in slots 190, will be sufficient to attach the rail 4 to the post 185. As a consequence, openings 188 may be reduced in length to a dimension substantially similar to the width of the horizontal portions 189.

Another alternative engagement configuration and method of engaging the rail 4 with a post 6 is illustrated in Figure 10 where the end of the upper bar 18 is configured so as to form a hook portion 100 and the upper slot 30 has an L-shape when viewed from above, the slot 30 has one portion on the side of the post 6 and another portion on the front of the post for receiving the bar 18. The hook portion

100 of the bar 17 is formed so it can be received within the slot 30 so the upper bar 18 abuts an end 102 of the slot 30 on the side of the post 6. The hook portion

100 then prevents movement of the bar 18 in the direction of the axis of the bar

18. Inserting the cap 8 onto the post 6 causes the vertical slot 42 of the cap 8 to engage the sides of the bar 18 and prevent lateral movement of the bar 18 from the slot 30.

A second alternative configuration for causing the upper bar 18 to engage a post 6 is illustrated in Figure 11. The end of the bar 18 again includes a hook portion 104, the hook portion 104 in this instance further includes a horizontal U- shaped channel 106 disposed in the centre thereof. The tope of the post 6 is provided with a reduced head portion 108 having a knob 110 which protrudes from the side of the head portion 108. The head portion and knob 110 are configured so the U-shaped channel 106 of the hook portion 104 engages the stem 112 of the knob 110 when the upper bar 118 is. pivoted towards the head portion 108. On engaging the stem 112, longitudinal movement in the direction of the axis of the upper bar 18 is prevented by the head portion 108 and the head of the knob 110

engaging with the hook portion 104. After slotting the channel 106 onto the stem 112, the cap 8 can be inserted onto the post 6 so the vertical slot 42 engages the sides of the bar 18 and prevents lateral movement of the bar 18, as described previously.

A third alternative configuration and method of attaching an upper bar 18 to

a post 6 is illustrated in Figure 12. For this arrangement, the bar 18 includes a hook portion 100 and the upper slot 30 in the post 6 is L-shaped, as is the case for the configuration illustrated in Figure 10 and described previously. In this instance,

however, the bar 18 is located at lower position relative to the post 6 and, accordingly, the slot 30 is also located at a lower position to receive the hook portion 100. In view of the lowered disposition of the slot 30 and the hook portion 100, a sleeve 120 is provided instead of the cap 8. The sleeve 120 is essentially the same as the cap 8 in that it includes the vertical slot 42, however, the top end has been removed so as to enable the sleeve 120 to slide along the post 6 until the vertical slot 42 engages the bar 18, as described previously.

The lower bar 22 could also be formed with the hook portions 100 and 104 in a similar manner to the upper bar 18, as described above, and the base 10 adjusted accordingly, if necessary.

Referring now to Figures 13 to 19, an improved barrier means 5, shown in

Figure 13, is provided instead of the barrier means 2 shown in Figure 1. Barrier means 5 comprises upper and lower horizontal members 7, 9, each of which is formed as an extruded metal section. The section may, as shown, be the same for each member.

Upright elements 11 extend between the members 7, 9.

Opposite ends of the elements 11 are received in the members 7, 9 to interconnect the elements 11 with the members 7, 9. Figure 14 shows the manner of assembly of one element 11 to member 7. The metal sections forming the members 7, 9 have elongate lengthwise extending cavities 25a each open to the exterior of the respective member via a respective slot 25b, so that each cavity and its associated slot together define a downwardly open respective T-shaped channel 25 extending lengthwise of the respective member 7, 9.

The elements 11 are each of similar form, comprising a central portion 33 of hollow tubular form, and two end portions 13, one positioned at each end of the central portion. Each end portion 13 has a cylindrical shank 35 neatly received in the respective end of the central portion 33. Each end portion 13 also has, at the free outer end thereof, a transversely extending enlarged head 41. Each head 41 is of shallow cylindrical form.

The end portions 13 are secured to the central portions 33 by peripherally inwardly swaging of the free ends 39 of the portions 33 into peripheral grooves 43 on the shanks 35, immediately adjacent the heads 41. In the alternative construction of Figure 15, the groove 43 is, however, on the shanks 35 between the ends thereof, and the swaging of the central portion 33 is effected by correspondingly positioned a peripheral groove 43a in the wall of the central portion 33.

The heads 41 and the adjacent ends of the central portions 33 present cross-sections, taken axially of the central portions 33, which are of T-shaped form, complementary to the cross-sectional form of the channels 25 in members 7, 9.

The end portions 13 of each element 11, and adjacent ends of the central portions 33, are neatly received in the channels 25 of respective members 7, 9. In particular, the heads 41 are accommodated in the cavities 25a whilst the ends of the central portions 33, with shanks 35 therewithin, extend outwardly therefrom and through the slots 25b. Thus, the central portions extend exteriorly of the members 7, 9. Because the side to side dimension of the heads 41 is greater than the side to side dimension of the slots 25b, withdrawal of the heads from the channels 25, under axial movement of the elements 11, is precluded.

The interconnections between elements 11 and member 9 is the same as that shown in Figure 15, using end portions 13 which are secured to the lower ends of the elements 11 and having heads 41 received in the channel 25 of the member 9, the member 9 in this case being oriented with the channel 25 upwardly open rather that downwardly open as in the case of the member 7.

The elements 11 extend in spaced parallel relationship between the members

7, 9. They are maintained in spaced relationship by spacers 15 positioned in each channel 25, one between each adjacent pair of end portions 13. As shown in Figures 13, 16, 17 and 24, each spacers 15 is of flat elongate form. Each is received in a channel 25, so as to extend in the lengthwise direction thereof.

Each of the spacers 15 is neatly retained in the cavity 25a. The ends of the spacers may be scalloped to define ends 15a which are arcuate and of complementary form to the periphery of the heads 41 so as to neatly abut these as shown.

This arrangement permits particularly simple assembly of the barrier means 5.

The elements 11 can first be assembled by fitting and securing the end portions 13 to the central portions as described. Then the elements 11 can be assembled to the members 7, 9 by sliding the heads 41 and adjacent ends of the central portions into the channels 25 from ends of the members 7, 9, the ends of the channels being open to -such ends of the members. As the heads are so slid into the channels, the spacers are likewise slid into the channels, alternating with the heads 41.

The elements 11 may be held in position relative to the lengths of the members 7, 9 in any suitable fashion and may be constrained against other movement, such as axial movement of the elements, or movement side to side of the members 7, 9, in any suitable way. In the case of the described barrier means 5, absolute securement against lengthwise movement is not essential.and can in any event be largely prevented by pressing the heads 41 and spacers 15 into abutment in the lengthwise direction of the channels 25, and securing end ones of the spacers 15, and or the elements 11, relative to the members, such as by screwing, welding, crimping or the like. In another form outermost ones of the spacers 15 in the channels 25 and abut against engaging parts next described and which are themselves held substantially fixed relative to the members by for example welding, screwing, crimping or by friction.

If very substantial resistance to movement of the elements 11, axially, or sidewardly of the members, is needed, any of the described means of securement may be applied. Generally, however, it is sufficient in the present application if the heads 41 and spacers 15 are made a slight interference fit in the cavities 25a, being dimensioned to be still relatively easily slidable in the cavities under slight resilient deformation of the walls of the members, but such as to still resist movement in the cavities (including movement lengthwise of the members 7, 9) by firm interengagement with the surfaces defining the cavities.

Of course, the heads 41 need not be of circular form when viewed axially of the elements 11, as shown. For example, they could be of rectangular form such as square, in which case they can be dimensioned so as to resist rotation in the cavities 25. The central portions may likewise be of different cross-section to the circular cross-section shown, such as to be complimentary form to the cross-section of the upright elements 11.

A particular advantage of the form of the members 7, 9 and elements 11 as shown is that it is possible to easily construct the barrier means 5 in any desired size or proportion, and to readily provide for different spacings of the elements 11, all as may be required for structural or aesthetic considerations. The members 7, 9 can be cut as required from lengths of extruded section, to suit particular end to end dimensional requirements for the barrier means, and the central portions of the elements 11 can be cut to desired lengths from tube stock, to provide a desired height for the barrier means. By forming the spacers 15 to preselected lengths, the spacing between elements 11 can be set accordingly in a simple manner. The spacers can be easily formed from bar stock by cutting and/or stamping predetermined lengths thereof to form the spacers. This is particularly simple if the spacers have linear ends extending normal to the lengths thereof, such as above heads 41 are square or rectangular. The end portions 13 may be conveniently formed as plastic mouldings. The spacers 15 may also comprise extrusions, preferably formed from aluminium.

In the described arrangement the central portions 33 are swaged to the shanks 35, but these could be secured together in other ways such as by frictional engagement, screwing, welding or the like. In cases where swaging is employed it is preferred to effect this at the ends of the central portions, as shown, for neatness of appearance. The swaging could however be effected otherwise such as previously mentioned in connection with Figure 16.

The barrier means 5 may interfit .with posts 6 in the same way as described in relation to the barrier structure 2 in the embodiment of Figure 1. Thus, the barrier means 5 is provided with four engaging parts 21 for this purpose, as shown in Figure

18. These have portions 27 which intcrfit within the cavities 25a, by sliding therein to from opposite ends of the members 7 and 9 so that one is positioned at each opposite end of each member 7, 9. The portions 27 may be arranged to be an interference fit in the cavities 25a, or they may be fixed therein by any of the affixing means previously described. In this case of frictional welding, the portions 27 could be somewhat wedge shaped and/or be serrated to facilitate gripping when driven into the ends of the channels 25 as before described. In this instance, each engaging part 21 has a generally L-shaped stem section 17 extending from the portion 27. This section extends, in the case of the upper most ones of the engaging part 21, downwardly through slot 25b and thence outwardly in the sideward direction of the barrier means 5, terminating in a protrusion or knob 31. In the case of the lower ones of the engaging parts 21, these have the portions 27 thereof positioned in the cavity 25a in relatively inverted position so that the stem sections 17 extend upwardly through the slot 25b and thence outwardly to terminate in a protrusion or knob 31. Knobs 31 perform the same function as the knobs 24, 26 in the arrangement of Figure 1.

Aside from these differences in construction, the barrier means 5 may be employed in the same fashion as the barrier means of the barrier structure 2 illustrated in Figure 1.

In Figure 19, a modified form of engaging part 49 is shown. This is fixed to the barrier means 5 in the same way as the engaging parts 21 just described and two of these replace the upper two engaging parts 21 of barrier means 5. In this case, however, the knob 31 of each engaging part is replaced by hook portion 29 which depends downwardly from the free outer end of the L-shaped section 17a affixed to the portion 27. Whereas in the engaging parts 21, the outwardly directed part at least of the L-shaped stem sections 17 are generally cylindrical, the whole of the stem section 17a may, if convenient, be formed from flat stock as shown. As mentioned, the lower engaging parts 21 may remain the same as shown in Figure 18, particularly having the outwardly extending part of sections 17 formed of circular cross section.

In Figure 19, the slots 51 at the upper parts of each post 6 which receive respective upper engaging parts 49 are somewhat differently configured to the upper post slots previously described. More particularly, each slot 51 comprises a horizontal portion 53 extending on a side surface of the post from a "front" edge 6a of the post 6 to a vertical portion 55 extending downwardly from the end of the slot portion 53 remote from the edge 6a of the post. The height "x" of the slot portion 53 is made greater than the height "y" of the hook portion 29 together with the adjacent end portion of section 17a of each engaging element 49.

To assemble the barrier means 5 having the described upper engaging parts 49 and lower engaging parts, a procedure somewhat similar to those previously described is followed. Thus, the knobs 31 of the lower engaging parts 21 of the barrier means 5 are positioned within the interiors of the posts 6 with the adjacent horizontally extending portions of sections 17 extending away from the posts through the slots 32 of the posts 6, in the same way as previously described. However, the slots 32 are in this case made of somewhat greater length than is the case in the arrangement of Figure 1, so that the engaging elements 21 may move vertically somewhat in these slots when the posts are assembled to the bases 10. After the posts 6 are initially assembled to the bases 10 to capture the engaging parts 21, but before the barrier means is upwardly swung, the barrier means is pulled upwardly in the slots 32. The outwardly extending portions of the sections 17 of lower engaging elements 21 are then positioned at upper ends of slots 32 as shown in Figure 20, whereas broken lines 17b in this figure show a lower permitted position in the slots under the condition that the parts 21 rest on the bases 10 in the way analogous to that illustrated in, for example, Figure 4.

The spacing between the slots 32 and the slots 51 on each of the posts 6 is in this case arranged so that when the barrier means is positioned at its upper location as shown in Figure 20, the hooked portions 29 may be entered into the slot portions 53 by swinging motion in the same fashion as shown in Figure 3 (see Figure 21). When so entered, the whole of the barrier means 5 may then be dropped downwardly to enter the portions 29 into behind the slots 55 in the fashion shown in Figure 22.

Then, the hooked portions pass below the lower edges 61 of slot portions 55 while the adjacent portions of sections 17a are captured in slot portions 55, so that movement of the barrier means 5 away from posts 6 is resisted by engagement of the portions 29 with the inner side surfaces of the posts 6 (Figure 23) and front to rear movement of the barrier means is presented by engagement of the sections 17a with slot portions 55. Once so assembled, it may be desirable to arrange for some locking to prevent the barrier means 5 from being pulled upwardly, and this may be effected by use of suitable locking means such as screws or the like or some arrangement for blocking the upper parts of the slots 32 or the upper parts of the slots 51 to prevent rising of the relevant parts in the slots. Generally speaking, however a secure enough arrangement may be provided without need for this, bearing in mind that the slots 42 in the caps 8 can as shown in Figure 23 be dimensioned to prevent such upward movement. In such case, it may still be preferable to provide some filling in the slots 32 above the engaging parts.

Of course, the parts 21 at the lower ends of the barrier means 5 may be replaced by parts similar to parts 49 although in this case it is preferred that the horizontally extending portions of the sections 17a be cylindrical.

As can be seen, the above described barrier structures are not readily applicable to sloping surfaces. For this purpose, a pivotal connector is provided instead of the above mentioned end portions.

The connector will now be described with reference to Figure 25 in which like parts to those above described will be represented by the same reference numerals. The connector 71 in the embodiment shown comprises a ball and socket joint 73. The ball 87 is housed in a socket 79 which is formed by split washers 81 and 83 which are preferably formed of nylon. The ball itself, is for example, also formed of nylon and may, as shown, be split for ease of manufacture so as to comprise a top hemisphere 75 and bottom hemisphere 77 which is formed integrally with a stem portion 85. The diameter of the ball may, for example, be approximately 25 mm, while the diameter of the stem portion 85 may be approximately 19 mm. The two

hemispheres have levelled edges 92 around the periphery of the join, so as to reduce any frictional effects between the edges and the socket 79. The top hemisphere is located relative to the bottom hemisphere by means of a pin 91 which is received from the top hemisphere 87 into an associated recess 93 of the bottom hemisphere 77. The recess may extend down through the whole extent of the bottom hemispher 77 and stem portion 85, as indicated by the dashed lines 94, in order to reduce the materials used in the construction of the connector 71.

The connector 71 is, in use, inserted into an elongate member 7. As mentioned in the above description, the member 7 is preferably formed of a metal section having an elongate lengthwise extending cavity 25a open to the exterior of the member via a slot 25b, so that the cavity and its associated slot together form a downwardly opening channel 25, divided in part by inwardly projecting portions 95, extending lengthwise of the member. The portions 95 may be located closer to the bottom of the member 7 and as a result, the washers 81 and 83 will be thinner. Thin washers are preferred as thinner washers will have a reduced manufacturing cost.

The socket 73 of the connector 71 once inserted into the channel is in firm contact with the bottom inside surface of the member 7 and the projecting portions 95.

Inserted in this manner, the stem portion 85 extends downwardly and out of the slot 25b. Tubular members or central portions 33 are fixed to the stem portions 85 by methods described above in relation to Figures 14 and 15.

Pivotal motion of the central portion 33 relative to the member 7, in a direction into and out of the page as viewed, is therefore possible by virtue of the ball and socket joint 73.

Similarly to the arrangement described with reference to Figures 13 to 19, spacers 15 may be inserted between the connectors as shown in Figure 26.

The above described engaging parts 21 of the barrier means may also have

connectors 71 attached thereto instead of portions 27, and a barrier means using the connectors 71 of the present invention may then interfit with posts 6 in the same way as described in relation to the barrier structure of Figures 1 and 13. This is particularly useful in the case where the barrier structure is to be erected on a sloping surface as shown in Figure 28. As can be seen, if the central portions 33 pivot relative to the elongate members 7 and 9, the central portions 33 may, in use, be arranged to extend vertically.

While the above description of the connectors has been limited to a ball and socket joint any other suitable pivotal means would suffice such as a pin which passes through the stem portion 85 and which is capable of being firmly located within the elongate member 7.