Technical Field

This disclosure relates generally to locking devices and more particularly, but not exclusively, to locking devices suitable for use with demountable or temporary fencing.

Background of the Disclosure

Demountable fencing, or temporary fencing, is used in many applications, for example on building construction sites to keep out members of the public, or for crowd control at large sporting or social events. When such fencing is assembled in use, it is normally used over a relatively short period of time, and so the fence panels are not fixedly mounted into surrounding ground, nor permanently joined side by side with one another in a row. However, in spite of the fence not intended to be a permanent fixture, it still needs to be able to remain upright when pushed or leant against, or when subjected to strong winds, for example. Demountable fencing is also intended to provide a barrier to offer some sort of site security, for example theft of building materials from a site, as well as for safety, for example by keeping unauthorised persons out of a fenced area.

Fence poles form at least the upright side sections of a fence panel. These fence poles are normally metallic, for example, elongate cylindrical galvanised iron tubes which are round shaped when viewed in a transverse cross-section. There are normally four such lengths of pole which form a square or rectangular shaped frame of an individual fence panel (left side upright, right side upright, top side horizontal and bottom side horizontal) and metallic mesh is then located within the said frame (by welding or some other fastening technique) to form a finished fence panel. When in use, the left and right side uprights are generally orthogonal to the surrounding ground on which the fence panel stands. The top side and bottom side poles are generally parallel to the surrounding ground on which the fence panel stands in use. An example prior art demountable fence is shown in Figure 1.

The left and right side upright poles of the fence panel normally extend some distance above and below the top and bottom side horizontal poles. These extended lengths are locations where a user can position a device to link the adjacent fence panels together, and to support the panels to stand upright on the surrounding ground. It is known to use rudimentary clamps to be fastened to the left and right side upright poles of a fence panel, and normally located (but not necessarily) above the height of the top side horizontal pole. Such clamps may comprise twin members which are generally elongate in shape, each having distal end portions which are curved so they are shaped to fit at least partially around the outer circumference of two adjacent fence poles. When positioned in use, the twin members are fastened together by means of a threaded bolt and hexagonal nut arrangement to clamp them both together, and in such a position that the curved distal end portions of each member are at least partially located around two adjacent upright side poles of two respective adjacent fence panels. Such a prior art device is shown in Figure 2, in which the twin members are fastened together and located in opposing alignment, to show how opposing curved distal end portions of the twin members define an area which is approximately circular, and which is arranged in use for receiving a side pole of a fence panel.

It is also known to use a rudimentary anchoring block which features adjacent cavities for insertion of the respective lowermost ends of the left and right side upright poles of adjacent fence panels, the lowermost ends being the region below the height of the bottom side horizontal pole of the fence panel(s). The cavities are of a size and shape to slidingly receive and to snugly support two adjacent upright poles on the sides of respective adjacent fence panels. Such a prior art device is shown in Figure 3.

The existing fence panel clamps and anchoring blocks do not offer any realistic site security or access control, and can be easily circumvented by unauthorised persons using basic tools from a toolkit. Summary

In a first aspect of the present disclosure, there is provided a locking device adapted for locking two adjacent fence poles in positional relation to one another, the locking device comprising a key-operated locking mechanism which is arranged for actuation between a first position in which the locking device is moved into engagement with said two fence poles, and retains each of them in a fixed position with respect to the other, and a second position in which the locking device is disengaged from at least one of said fence poles, and the poles are able to be moved apart from one another.

The use of a key-operated locking mechanism means that the locking device cannot be tampered with or removed from engagement with the adjacent fence poles unless a key has been provided, thereby increasing security and improving safety in the fenced-off area. In each of the embodiments which have been devised, two adjacent fence poles can be retained in position by using a locking device which is placed in engagement with any portion of each of the respective poles, to achieve the desired improvement in security and safety while being tamper-proof.

When the term "key-operated" is used in relation to a locking mechanism in the present specification, the key is defined as any type of specific tool or device which is designed to turn the mechanism of a lock, being of a unique form for this function. The "key" therefore may not be in the traditional form of a jagged house key cut from metal, used to mate with a specific tumbler lock mechanism for example, but could be in another unique form or proprietary style, such as a specific design of prong, pin or other selectively-shaped member. This definition necessarily excludes tools which are routinely found in a toolkit and which are not designed for unique use, such as screwdrivers or chisels.

When the terms "engaged" or "engagement" are used in relation to the use of a locking device in the present specification, this means that the device has at least some contact with each of the two adjacent fence poles, sufficient to ensure that the two poles remain at a fixed distance from one another, and cannot be moved apart from one another by any significant distance. In some embodiments, the engagement may be such that the device is tightly fitted to one or both of the poles, and in yet other embodiments the device may only need to be loosely fitted so as to circumscribe one or both of the poles when in use, and be seated thereat at a few points of contact.

Additionally, when the terms "to be clamped" or "become clamped" are used in relation to a locking mechanism in the present specification, this is to be interpreted in the same sense as to be "engaged" or being in "engagement".

In some embodiments, the device includes two arms which in the first position are arranged for engagement with an outer surface of a respective fence pole.

In some embodiments, an end region of each of the respective arms is curved in a half-ring shape, and an inner surface of each of the half rings is concentric with an outer surface of the fence pole.

When the term "concentric" is used in relation to a locking mechanism in the present specification, the inner curved shape of the arms of the device and the curvature of the exterior of the fence poles need not be exactly the same nor perfectly concentrically arranged, and should be interpreted to encompass loose fitting engagement therebetween.

In some embodiments, when in the second position, the two arms are sufficiently spaced apart at their respective end regions so that a fence pole can be laterally moved therebetween, such movement being both into and out of an opening which exists between the end region of the two arms.

In one arrangement, the arms are biased to remain in the second position until actuation of a key in the key-operated locking mechanism causes pivoting of the arms into the first position. In one form of this, actuation of the key can be by rotation thereof. Other ways of actuating key (for example, by sliding, or pushing) are possible, in order to cause pivoting of an elongate member which is in contact with a respective inner end region of each arm which is opposite to the end region, causing the inner end regions of the arms to be moved away from one another, thereby causing the end regions of the respective arms to moved towards one another and into the first position. In some embodiments, the device includes two pairs of arms located at opposite ends of a body which houses the locking mechanism.

In one form of this, the device includes two locking mechanisms, independently operable on each pair of arms which are arranged for engagement with a respective fence pole.

In an alternative form, the device includes a single locking mechanism, simultaneously operable on both pairs of arms which are arranged for engagement with a respective fence pole.

In an alternative series of embodiments, the device of the first aspect includes two elongate, slidingly moveable members, an outer end portion of which is arranged to be received into a corresponding opening located in a respective fence pole when in the first position. In some embodiments, the opening is a hole in an outer wall of a hollow fence pole.

In some embodiments, the moveable members in the second position are retracted into a housing which is located in use between the two respective fence poles.

In one arrangement, the slidingly moveable members are biased to remain in the second position until actuation of a key in the key-operated locking mechanism at the housing causes sliding of the said members into the first position. In one form of this, actuation of the key can be by rotation, so as to cause pivoting of an elongate member which is in contact with a respective inner end portion of each slidingly moveable member which is opposite to the outer end portion, causing the inner end portion of the arms to be moved away from one another, thereby causing the outer end portion of the respective arms to slide into the first position.

In some arrangements, the housing includes a support member configured for locating each of the two adjacent fence poles at the housing. In one arrangement, the support member is a cap which is arranged in size to be positioned in use over the uppermost end of each fence pole. In one form of this, each of the caps are located at distal ends of the housing. In another arrangement, the seating member is a socket which is arranged in size to be positioned in use under the lowermost end of each fence pole. In one form of this, each of the sockets are located at distal ends of the housing. In such an arrangement, the housing and sockets can be located within a base member made of a dense material to anchor the fence poles and associated fence.

In some embodiments, when moving between the first and second positions, the distance between the arms is adjustable by a relative sliding movement of one or both arms toward or away from one another along a concentric shaft.

In some embodiments, each arm includes an opening arranged in use for sliding receipt of the shaft therethrough. In one arrangement of this, the openings comprise aligned through-holes located in a central portion of each arm.

In some embodiments, said concentric shaft is arranged to be slidingly adjustable along its axis with respect to the key-operated locking mechanism until actuation of a key locks the locking mechanism to the shaft.

In some embodiments, a distal end portion of the concentric shaft extends beyond an outer side face of one arm, said end portion having an element which is moveable so as to be in abutment with that outer side face, and wherein the locking mechanism has an element which is moveable so as to be in abutment with an outer side face of the other arm, such that in use by sliding the shaft along its axis relative to the locking mechanism, at least one of said elements of the distal end portion of the shaft and/or of the locking mechanism is moved into abutment with said respective outer side face of said respective arm(s), resulting in the relative sliding movement of the or each arm toward one another until the first position is reached.

In some alternative embodiments, (a) a distal end portion of the concentric shaft is operatively connected to one arm, and/or (b) the locking mechanism is operatively connected to the other arm, such that in use by sliding the shaft along its axis relative to the locking mechanism, said operative connection(s) provide a relative sliding movement of the or each arm toward one another until the first position is reached.

For either of those alternatives, in some arrangements a subsequent actuation of the key to lock the key-operated locking mechanism to the shaft secures the said arms in the first position. In one embodiment of this, the locking mechanism engages with a surface configuration feature of the shaft which enables it to become locked thereto.

In some embodiments, when operatively coupled in the first position, an adjacent portion of both arms are arranged in a close facing relationship having a distance therebetween which is fixed by a predetermined dimension of the key-operated locking mechanism.

In some embodiments, when the key-operated locking mechanism is operatively coupled to both arms to locate and retain them in said first position, an adjacent portion of each arm is arranged to fit within a predetermined dimension of said locking mechanism.

In either of these situations, the manner by which said arms are operatively coupled to the locking mechanism in use is substantially concealed from the exterior of the locking mechanism.

In some embodiments, each arm includes an opening arranged in use for sliding receipt of a concentric shaft therethrough. In one arrangement of this, the openings comprise aligned through-holes located in a central portion of each arm.

In some embodiments, said concentric shaft is arranged to be slidingly adjustable along its axis with respect to the key-operated locking mechanism until actuation of a key locks the locking mechanism to the shaft.

In some embodiments, when in the first position, said concentric shaft is substantially concealed from view by said adjacent portions of the two arms, and by a body of the key-operated locking mechanism.

In a second aspect of the present disclosure, there is provided a method for locking two adjacent fence poles in positional relation to one another, the method comprising the steps of: locating two fence poles in an adjacent position to one another; arranging a locking device comprising a key-operated locking mechanism between the two poles; and actuating said key-operated locking mechanism so that the locking device becomes engaged with the two fence poles, to retain each of them in a fixed position with respect to the other. In some embodiments, the method further comprises the step of arranging two arms to be operatively connected to the locking device so that the step of actuating said key-operated locking mechanism causes said arms to become engaged with the two fence poles.

In some embodiments, the steps for the method of operation of the two arms use one or more of any of the operable features of the arms, as previously defined for the first aspect.

In some embodiments, the steps for the method of operation of the key-operated locking mechanism uses one or more of any of the operable features of the locking mechanism, as previously defined for the first aspect.

In a third aspect of the present disclosure, there is provided a system for locking two adjacent fence poles in positional relation to one another, comprising at least one locking device which is arranged in use to be engaged with said two poles, the locking device comprising a key-operated locking mechanism which can be actuated to become engaged with the two fence poles, and to retain them in a fixed position with respect to the other.

In some embodiments of the system, the locking device further comprises two arms arranged in use for engagement with the poles.

In some embodiments, the two arms have one or more of any of the features of the apparatus previously defined in the first aspect.

In some embodiments, the key-operated locking mechanism has one or more of any of the features of the apparatus previously defined in the first aspect.

In a fourth aspect of the present disclosure, there is provided a method of retrofitting a locking device which used to lock two adjacent fence poles in positional relation to one another, the method comprising the steps of: identifying the location of two fence poles which are locked in an adjacent position to one another using a prior art locking device engaged therebetween; arranging a replacement locking device for engagement with the two poles, the replacement locking device comprising a key- operated locking mechanism having one or more of any of the operational features of the locking mechanism which was previously defined in the first aspect; disengaging the prior art locking device from the two fence poles; and actuating said replacement locking device to be in engagement with the two fence poles, to retain each of them in a fixed position with respect to the other.

Other aspects, features, and advantages will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, which are a part of this disclosure and which illustrate, by way of example, principles of the inventions disclosed.

Description of the Figures

The accompanying drawings facilitate an understanding of the various embodiments which will be described:

Figure 1 is a perspective view of a prior art demountable fence;

Figure 2 is a schematic plan view of a prior art clamping device used for joining the left and right side upright poles of two adjacent fence panels;

Figure 3 is a schematic, cross-sectional view of a prior art locking device in accordance with Figure 1;

Figure 4 is a schematic view of a locking device in accordance with a first embodiment of the present disclosure, when positioned in a first (closed) position;

Figure 5 is a schematic view of the locking device in accordance with Figure 4, when positioned in a second (open) position;

Figure 6 is a schematic, cross-sectional view of the locking device in accordance with Figure 4;

Figure 7 is a schematic, cross-sectional view of the locking device in accordance with Figure 5; Figure 8 is a schematic view of a portion of a locking device in a housing, in accordance with a second embodiment of the present disclosure, when positioned in a first (closed) position;

Figure 9 is a schematic view of the portion of the locking device in accordance with Figure 8, when positioned in a second (open) position;

Figure 10 is a schematic, cross-sectional view of the portion of the locking device in accordance with Figure 8, with a pole support member in the form of a cap located at either end of the housing;

Figure 11 is a schematic, cross-sectional view of the locking device incorporating the embodiment in accordance with Figure 8;

Figure 12 is a schematic, cross-sectional view of the locking device incorporating the embodiment in accordance with Figure 9;

Figure 13 is a schematic view of a locking device in accordance with a third embodiment of the present disclosure, with a pole support member in the form of a socket located at either end of the housing;

Figure 14 is a schematic view of the locking device of Figure 13, when positioned within a base member made of a dense material;

Figure 15 is a schematic, cross-sectional view of a locking device in accordance with Figure 13, when positioned in a first (closed) position; and

Figure 16 is a schematic, cross-sectional view of a locking device in accordance with Figure 13, when positioned in a second (open) position.

Figure 17 is a perspective view of a key-operated locking mechanism, shown positioned on a shaft, where the shaft is arranged to be slidingly adjustable along its axis with respect to the locking mechanism;

Figure 18 is a schematic, cross-sectional view of a locking device in accordance with a fourth embodiment of the present disclosure, when positioned in a second (open) position, the locking device comprising the key-operated locking mechanism of Figure 17 in which the shaft, locking mechanism and two device arms are discrete items (so the locking device can be supplied as four items);

Figure 19 is a schematic, cross-sectional view of a locking device in accordance with a fifth embodiment of the present disclosure, when positioned in a second (open) position, the locking device comprising the key-operated locking mechanism of Figure 17 in which the shaft is attached in a fixed manner to one device arm, with the remaining device arm and the locking mechanism being discrete items, (so the locking device can be supplied as three items);

Figure 20 is a schematic, cross-sectional view of a locking device in accordance with a sixth embodiment of the present disclosure, when positioned in a second (open) position, the locking device comprising the key-operated locking mechanism of Figure 17 in which one end of the shaft is attached in a fixed manner to one device arm, and the other end of the shaft is connected to the locking mechanism, and the second device arm is located on the shaft therebetween, (so the locking device can be supplied as one coupled item);

Figure 21 is a top, front-side, perspective view of a key operated locking mechanism shown positioned on a shaft, where the shaft is arranged to be slidingly adjustable along its axis with respect to the locking mechanism;

Figure 22 is an underside, front, perspective view of the key operated locking mechanism of Figure 21, with a minor variation in the shape of the protrusion located at the end of the shaft;

Figure 23 is a schematic, cross-sectional view of a locking device in accordance with a seventh embodiment of the present disclosure, when positioned in a first (closed) position, the locking device comprising the key-operated locking mechanism of Figure 21 or Figure 22 in which the shaft and locking mechanism separable, along with two device arms supplied as discrete items (so the locking device can be supplied as four items);

Figure 24 is a schematic, cross-sectional view of a locking device in accordance with Figure 23, when positioned in a second (open) position; Figure 25 is a schematic, cross-sectional view of a locking device in accordance with an eighth embodiment of the present disclosure, when positioned in a second (open) position, the locking device comprising the key-operated locking mechanism of Figure 21 or Figure 22 in which each of the shaft and locking mechanism are supplied when attached in fixed manner to a respective device arm (so the locking device is supplied as two items);

Figure 26 is a schematic, cross-sectional view of a locking device in accordance with a ninth embodiment of the present disclosure, when positioned in a second (open) position, in which the locking device comprises the key-operated locking mechanism of Figure 21 or Figure 22 but where the shaft is supplied when attached in fixed manner to a respective device arm, but the locking mechanism and the other arm and not attached (so the locking device is supplied as three items);

Figure 27 is a schematic, cross-sectional view of a locking device in accordance with a tenth embodiment of the present disclosure, when positioned in a first (closed) position, in which the locking device comprises a key-operated locking mechanism of type which is shown in each of Figures 28 to 31 for which the key-operated locking mechanism is operatively coupled to both arms to locate and retain them in the first position. In each example, a portion of each of the arms is located within a predetermined, confined dimensional space that is defined by the particular shape of the locking device, to hold them close together and also to concealing how the arms are mounted thereto by the shaft.

Figure 28a to 28e are a series of perspective views of a key operated locking mechanism shown having two generally triangular-shaped opposing end brackets with a short shaft arranged therebetween (the shaft being accessible by disassembly of one end bracket by unscrewing), and which in use can be operatively coupled to both arms to locate and retain them in the first position;

Figure 29a and 29b are a back and front perspective view of a key operated locking mechanism shown having two generally rectangular end brackets with a short, retractable shaft arranged therebetween, and which in use can be operatively coupled to both arms to locate and retain them in the first position; Figure 30 is a front perspective view of a key operated locking mechanism shown having a generally U-shaped form with rectangular end brackets with a short, decouplable shaft arranged therebetween, which in use can be operatively coupled to both arms to locate and retain them in the first position;

Figure 31 is a front perspective view of a key operated locking mechanism shown having a generally cylindrical form with circular cross-section end brackets with a short, decouplable shaft arranged therebetween, which in use can be operatively coupled to both arms to locate and retain them in the first position.

Detailed Description

This disclosure relates to the features of a number of different types of fence pole locking devices, where the fence poles form at least the upright side sections of a fence panel, as was already described in relation to Figure 1.

Referring to Figures 4 to 7, a locking device 10 is disclosed which is in the form of an elongate, rectangular- shaped housing 12 which has two pairs 14, 16 of arms 18, 20, 22, 24 extending from opposite ends of the housing 12. A locking mechanism is located within the housing 12. Each of the end regions of the arms is curved into a half- ring shape 26, and an inner semi-circumferential surface 28 of each half-ring shaped end region 26 is shaped so as to be concentric with an outer surface of the circular cross- section fence pole 30 to which the locking device 10 becomes clamped in use. Therefore, when a pair 14, 16 of arms (18 and 20; 22 and 24) is moved into a position to become clamped onto a respective fence pole 30, the inner surface 28 of each half-ring shaped end region 26 will be located in a close facing relationship with the outer surface 32 of the circular cross-section fence pole 30, to provide at least some surface contact therebetween.

In one such an arrangement, the locking device 10 can be reasonably loosely fitted to the side upright fence poles 30 of two adjacent panels of temporary fencing, so that the inner surface 28 of each half-ring shaped end region 26 is approximately concentrically aligned with the outer surface 32 of the respective circular cross-section side fence pole 30, and there is at least some contact possible therebetween. In such an arrangement, it is easy for a user to adjust the angle of orientation of two adjacent panels of fencing by pivoting a first panel relative to a second panel by rotation about the axis of the upright fence pole 30 of the first panel. During such a movement, the locking device 10 will still remain engaged around the respective side fence poles 30 of the two adjacent panels, ensuring that the two panels remain at a fixed distance from one another, and cannot be moved apart from one another by any significant distance.

In another arrangement, for greater rigidity of the temporary fencing being erected, the locking device 10 can be reasonably tightly fitted to the side upright fence poles 30 of two adjacent panels of temporary fencing, so that the inner surface 28 of each half-ring shaped end region 26 has maximum interference contact with, and is in concentric alignment with, the outer surface 32 of the respective circular cross-section side fence pole 30. In such an arrangement, if each pair of arms 14, 16 is arranged to grip tightly onto a respective, adjacent fence pole 30, so that once the fence has been constructed, the established angle of orientation of two adjacent panels of fencing cannot be altered until the locking device 10 is disengaged from at least one of the respective side fence poles 30 of the two adjacent panels to permit its relative movement.

In other embodiments, the shape of the arms can be dictated by the particular application of post or pole to which the device is to be clamped. For example, if the poles were square posts in cross-section, the end region of the arms can accordingly have an inner surface which mates with the external surface shape of the square post(s). In still other embodiments, it is possible to have the end regions of the two pairs of arms to have different shapes at respective ends of the housing, which can be useful in instances where, say, a round cross-section pole on one fence panel needs to be clamped to, say, a square cross-sectional post on an adjacent fence panel, or onto a wall section, or another type of fixed fence.

As shown in Figures 5 or 7, the end regions 26 of the arms 18, 20, 22, 24 are able to be moved apart from one other sufficiently to permit the locking device 10 to be able to slide laterally onto the fence pole 30, and the pole 30 fits into the mouth 36 formed between the said two end regions 26 of each of the pairs of arms (18 and 20; 22 and 24), and then moved into the clamped position as shown in Figures 4 or 6. This is useful, because it allows the locking device 10 to be positioned by lateral sliding onto the fence pole 30 at any vertical height above the surrounding ground, rather than only being able to slide over the uppermost top ends 38, 40 of two respective, adjacent fence poles 30, 30A. However, it is still expected that placement of the locking device 10 in the uppermost end region of adjacent fence poles 30, 30A is likely, as this is common practice in the prior art, as shown in Figure 1.

In the embodiment shown in Figures 6 and 7, the arms (18 and 20; 22 and 24) have straight stem arm portions 42 which are located at the distal end to the end regions of half-ring shape 26. The straight stem arm portions 42 are positioned within the housing 12 of the locking device 10. The straight stem arm portions 42 are biased to remain in the open position (Figures 5, 7) until rotation of a key in the key-operated locking mechanism 44 causes pivoting of the arms (18 and 20; 22 and 24) into the locked position (Figures 4, 6). As shown in Figures 6 and 7, rotation of a key actuates pivoting of a locking mechanism 44, which is engaged to each of the straight stem arm portion 42 of each of the four arms (18 and 20; 22 and 24). When moving from the locking device open position (Figure 7) to the closed position (Figure 6), the pivoting of the locking mechanism 44 causes each pair of opposing straight stem arm portions 44 to be moved away from one another (as seen in Figure 6), thereby causing the mouth 36 to close as the end regions of half-ring shape 26 are moved towards one another to clamp the device 10 onto the fence pole 30 (in the orientation shown in Figure 6).

In the embodiment shown in Figures 4 to 7, the locking device 10 has a single key-operated locking mechanism 44 which simultaneously pivots both pairs of arms (18 and 20; 22 and 24) when it is rotated and operated by use of a key. In further embodiments, it is possible to have two key-operated locking mechanisms which are independently operable on each pair of arms which are arranged to clamp a respective fence pole. In such an arrangement, the locking device can be undamped from one fence pole but can remain clamped to an adjacent fence pole, which may be more convenient in some situations for gaining temporary access through the demountable fence.

Referring now to the embodiment shown in Figures 8 to 12, the locking device 50 disclosed is in the form of an elongate, rectangular shaped housing 52 which has two elongate, slidingly moveable cylindrical members in the form of rods 54, 56 which can be retracted into the housing 52 (as shown in Figures 9, 12) or extended therefrom (as shown in Figures 8, 11). The rods 54, 56 are arranged to extend from, or retract into, the distal ends 68, 70 of the housing 52. An outer end portion 58, 60 of each rod 54, 56 is received in use into a correspondingly-sized hole which is located in the wall of a hollow, adjacent fence pole 30, 30A when the device is moved into the locking position (as shown in Figures 8, 11). The key-operated locking mechanism 62 is housed within the housing 52.

Referring to Figure 10, the housing 52 is arranged in use between two adjacent fence poles 30, 3 OA, and it includes a support member in the form of two hollow caps 64, 66 which are circular in cross-section and which are joined to the distal ends 68, 70 of the housing 52. The caps 64, 66 are arranged in size to be snugly positioned over the uppermost end 38, 40 of each of the adjacent fence poles 30, 30A so that the caps 64, 66 and the housing 52 bridge the space therebetween. In use, the caps 64, 66 support the fence poles 30, 30A in vertical alignment at the housing 52, and serve to align the centres of the hole(s) in the wall of the fence pole(s) 30, 30A with the lateral axis of movement of the rods 54, 56. In other arrangements, the caps can be configured in other shapes and forms, depending on the sort of pole being used. In other arrangements, the caps can also be joined to the housing in a different way, rather than being joined at the walls of the distal ends 68, 70 thereof.

Referring now to Figures 11 and 12, the slidingly moveable rods 54, 56 are biased to remain in the retracted position (Figure 12) until rotation of a key in the key- operated locking mechanism 62 at the housing 52 causes sliding of the rods 54, 56 into the extended (locking) position (Figure 11). The rotation of the key by the user actuates the pivoting of a part of the locking mechanism 62 which is itself pivotally engaged to an inner end portion 72, 74 of each of the rods 54, 56 within the housing. Pivoting the locking mechanism 62 therefore causes the inner end portion 72, 74 of the rods 54, 56 to be moved away from one another in an axial direction, thereby causing the outer end portions 58, 60 of the respective rods 54, 56 to slide into the corresponding receiving holes located in the adjacent fence poles 30, 30A (as shown in Figure 11).

Referring now to the embodiment shown in Figures 13 to 16, the locking device 50B disclosed is similar in configuration and operation to the device 50 described in relation to Figures 8 to 10, and so like operable parts have been designated the same part number with the suffix "B". The locking device 50B is in the form of an elongate, rectangular shaped housing 52B which has two elongate, slidingly moveable cylindrical members in the form of rods 54B, 56B which can be retracted into the housing 52B (Figure 16) or extended therefrom (Figure 15) at the distal ends 68B, 70B of the housing 52B. An outer end portion 58B, 60B of each rod 54B, 56B is received in use into a correspondingly-sized hole in a lowermost or base portion 76, 78 of an adjacent fence pole 30, 3 OA.

Referring to Figures 13 and 14, the housing 52B is arranged to be located between two adjacent fence poles 30, 3 OA, and has a support member in the form of two hollow sockets 80, 82 which are circular in cross-section and which are joined to the opposite ends 68B, 70B of the housing 52B. The sockets 80, 82 are arranged in size to be snugly positioned in use under the lowermost end 76, 78 of each of the adjacent fence poles 30, 30A so that the sockets 80, 82 and the housing 52B will bridge the space therebetween. In use, the sockets 80, 82 support the fence poles 30, 30A in vertical alignment at the housing 52B, and serve to align the centres of the hole(s) in the wall of the fence pole(s) with the axis of movement of the rods 54B, 56B. In other arrangements, the sockets can be configured in other shapes and forms, depending on the sort of pole being used. In the present embodiment, the housing 52B and sockets 80, 82 are located within the centre of a base member in the form of a footing 84 which is made of a dense material so as to securely anchor the fence poles 30, 30A and the associated fence. The footing 84 can be made of concrete, metal or other heavy materials, for example. The housing 52B and the sockets 82, 84 are accessible from an upper surface 86 of the footing 84, as is the location for actuation of the rotation of a key in the key-operated locking mechanism 62B at the housing 52B to cause sliding of the rods 54B, 56B into the extended (locking) position.

Referring now to the embodiments of a locking device 110 which are shown in Figures 18 to 20, the end regions 126 of the two arms 118, 120 are able to be moved apart from one other sufficiently to permit the locking device 110 to be able to slide laterally onto a fence pole, where the pole fits into the mouth 136 formed between the said two end regions 126 of the pairs of arms (118 and 120), and then moved into the clamped position by moving the arms 118, 120 towards one another. This is useful, because it allows the locking device 110 to be positioned by lateral sliding onto a fence pole at any vertical height above the surrounding ground. In the embodiment shown in Figures 17, 18, 19 and 20, the arms 118, 120 have straight stem arm portions 142, 144 which are located in a generally central region of each of the arms and in between the end regions 126. In these embodiments, when moving between the first and second positions, the distance between the arms is adjustable by a relative sliding movement of one or both of the arms toward or away from one another along a concentric shaft 150. The central region of each arm 118, 120 has a through hole 152, both said holes being linearly aligned, and each being wide enough for the shaft 150 of the locking mechanism to slide therethrough.

In the embodiment shown in Figure 17, a key-operated locking mechanism 154 is shown which is arranged for slidable positioning on the shaft 150. Generally, if the locking mechanism 154 is held stationary, the shaft 150 can be caused to slide freely in its own axial X-X direction past the locking mechanism 154, until the key 156 is actuated, at which point the locking mechanism 154 will be engaged with one of the six, spaced-apart recesses 158 shown arranged along and extending circumferentially into the body of the shaft 150.

The advantage of using a sliding shaft arrangement is that there is greater flexibility in terms the spacing of the arms 118, 120, and the lock 154 is readily able to be disengaged and quickly moved by sliding before being re-engaged at the shaft 150. It is not easy to change the distance between the arms by using a screwdriver or a pair of pliers to rotate the screw head or fastening nut of the conventional equipment.

The prior art screw-type mechanisms have threads which, over a period of time, can become rusted or blocked by dirt and debris which means that the locking device seizes up and cannot be easily disengaged from the fence without cutting the device off (for example, cutting off the screw bolt), or applying brute force, or necessitating the use of some specialty tools.

The locking mechanism shown in Figure 17 is generally known as a hitch pin lock, or coupler lock, and can find use in trailer towing applications. Such devices have a nickel-plated steel shank and brushed aluminium lock for enhanced corrosion resistance as well as strength. As shown in Figure 18, the locking device comprising the key-operated locking mechanism of Figure 17 features the ribbed recessed shaft 150, the key-locking mechanism 154 and the two device arms 118, 120, all of which are discrete items, (in other words, the locking device can be supplied as four component items).

In use, one end portion 160 of the shaft 150 extends beyond an outer side face 164 of the straight portion 142 of the arm 118, and this end is formed with a head 162 which comprises a wider diameter formation than the remainder of the shaft 150. The underside annular surface 166 of the head 162 (that is, the area located between the outer diameter of the shaft 150 and the outer diameter of the head 162) can be moved into abutment with the outer side face 164 of the arm 118 during use. Similarly, the uppermost flat surface 168 of the sliding locking mechanism 154 can be moved into abutment with the outer side face 170 of the central region of the other arm 120, when an operator slides the shaft 150 along its own axis X-X in the direction generally toward the locking mechanism 154. Once the shaft 150 and the locking mechanism 154 are engaged at the respective outer side faces 164, 170 of the two arms 118, 120, drawn closer together by the axial movement of the shaft 150, the locking device 154 will reach the first position (i.e. be clamped to the fence posts) and then be fastened into place by actuation of the key-operated locking mechanism 154 as it engages with a locking groove 158 conveniently located along the shaft 150. Once the lock 154 is engaged, its fastening clasp cannot pop out of the groove 158 and become unlatched.

In some alternative embodiments which are shown in Figure 19 and Figure 20, the only difference in the configuration compared with Figure 18 is whether a more permanent operative connection is implemented between the head 162 of the shaft 150 being connected to one arm 118, for example by joining these together with a threaded nut 172 (Figure 19). Alternatively (or even additionally) a more permanent operative connection can be implemented between the locking mechanism 154 and the other distal end 176 of the shaft 150, such as by placing a threaded nut 174 at that end (Figure 20).

In the embodiment shown in Figure 19, because the shaft 150 is attached in a fixed manner to one device arm 118, with the remaining device arm 120 and the locking mechanism 154 being discrete items, the finished locking device 110 is supplied as three discrete parts. In the embodiment shown in Figure 20, the head 162 of the shaft 150 is attached in a fixed manner to one device arm 118, and the other end of the shaft 176 is connected to the locking mechanism 154, so that the second device arm 120 is located (to freely slide) on the shaft 150 therebetween and cannot escape. This means that the whole the locking device 110 can be supplied as one coupled-together item in a kit, so that the parts are not misplaced, lost or dropped during assembly.

Turning now to the embodiment shown in Figures 21 to 26, the locking device disclosed is similar in its general operation to the device described in relation to Figures 17 to 20, and so like functional parts have been designated the same part number but with the suffix "B".

In Figures 21 and 22, a key-operated locking mechanism 154B, is shown for slidable positioning on a smooth cylindrical shaft 150B which has a wide end head 162B section (cylindrical-shaped in Figure 21, domed-shaped in Figure 22). Operating on a similar principle to the previous embodiments, the shaft 150B can slide freely in an axial direction past the locking mechanism 154B, until the key is actuated, at which point the locking mechanism 154B engages and the shaft 150B no longer moves relatively axially.

This type of key-operated locking mechanism is also known as a Pin Lock and sometimes finds use as a substitute for the clevis pin at the front mounting point of the operating mechanism for a swing-open driveway gate.

Referring to Figures 23 to 26, the key-operated locking mechanism of Figure 21 or Figure 22 in which the shaft and locking mechanism separable, is shown in various configurations with the two device arms.

The embodiment shown in Figures 23 and 24 is supplied with all items being discrete, so there are four components in total, shown in the respective second position (open, disengaged from pole) and the first position (closed, engaged to pole). The embodiment shown in Figure 25 uses the same key-operated locking mechanism of Figure 21 or Figure 22, but in this example, each of the shaft 150B and locking mechanism 154B are supplied being attached in fixed manner to a respective device arm (so that the locking device HOB is supplied as two items). For example, the key- operated locking mechanism 154B is joined by welding 180 to the arm 120B, and the shaft 150B is joined with a threaded nut 172 to the arm 118. In the embodiment shown in Figure 26 the shaft is supplied when attached in fixed manner to a respective device arm, but the locking mechanism and the other arm are not attached (so this locking device is supplied as three items).

Finally, Figures 27 to 31 show further types of key-operated locking mechanisms which are operatively coupled to both arms so as to locate and retain them in the first position. In each example, and as shown schematically in Figure 27, a portion of each of the arms is located within a pre-determined, confined dimensional space that is defined by the particular shape of the locking device, both to hold the arms closely together in the first position, and also to concealing how the arms are mounted thereto by the shaft.

Figure 28a to 28e show a key operated locking mechanism having two generally triangular- shaped opposing end brackets with a shaft arranged therebetween (the shaft being accessible by unlocking the mechanism and then disassembly of one end bracket by unscrewing), and which in use can be operatively coupled to both arms to locate and retain them in the first position.

Figure 29a and 29b show a key operated locking mechanism shown having two generally rectangular end brackets with a retractable shaft arranged therebetween, and which in use can be operatively coupled to both arms to locate and retain them in the first position.

Figure 30 shows a key operated locking mechanism having a generally U- shaped form with rectangular-shaped end brackets arranged with a decouplable shaft extending therebetween, which in use can be disengaged and operatively coupled to both arms to locate and retain them in the first position.

Figure 31 shows a key operated locking mechanism having a generally cylindrical form with circular cross-section end brackets with a decouplable shaft arranged therebetween, which in use can be operatively coupled to both arms to locate and retain them in the first position.

The above embodiments of a locking mechanism for locking adjacent fence poles in positional relation to one another can: prevent tampering of joined panels demountable fencing unless by authorised persons;

increase security at building sites and other premises;

improve safety by restricting access to premises by children or unauthorised persons;

allow ease of operation by use of an arrangement in which the components slide and then become coupled in position without the need for threaded screwing and unscrewing, which means less labour time and hand injuries; and

permit a simple retrofitting procedure to replace prior art locking mechanisms with a more effective one.

In the foregoing description of certain embodiments, specific terminology has been resorted to for the sake of clarity. However, the disclosure is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes other technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as "upper" and "lower", "above" and "below" and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms.

In this specification, the word "comprising" is to be understood in its "open" sense, that is, in the sense of "including", and thus not limited to its "closed" sense, that is the sense of "consisting only of. A corresponding meaning is to be attributed to the corresponding words "comprise", "comprised" and "comprises" where they appear.

The preceding description is provided in relation to several embodiments which may share common characteristics and features. It is to be understood that one or more features of any one embodiment may be combinable with one or more features of the other embodiments. In addition, any single feature or combination of features in any of the embodiments may constitute additional embodiments.

In addition, the foregoing describes only some embodiments of the inventions, and alterations, modifications, additions and/or changes can be made thereto without departing from the scope and spirit of the disclosed embodiments, the embodiments being illustrative and not restrictive.

Furthermore, the inventions have described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be

5 understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the inventions. Also, the various embodiments described above may be implemented in conjunction with other embodiments, e.g., aspects of one embodiment may be combined with aspects of another embodiment to i o realise yet other embodiments. Further, each independent feature or component of any given assembly may constitute an additional embodiment.