FENCING DEVICES, SYSTEMS AND METHODS RELATED APPLICATIONS

This application claims priority to Australian Provisional Patent Application No. 2007904829 in the name of Gryffin Pty Ltd, which was filed on 6 September 2007, entitled "Fencing Devices, Systems and Methods" and the specification thereof is incorporated herein by reference in its entirety and for all purposes. FIELD OF INVENTION

The present invention relates to fencing devices, systems and methods. Whilst the present invention is discussed with particular regard to mesh fences it is to be appreciated that the present invention is also applicable to other fences comprising relatively thin walled fences and, accordingly it should be appreciated that the present invention is not limited to use in relation to mesh fencing, only. BACKGROUND ART

Transporting and manufacturing relatively large fence panels can be problematic for a number of reasons. For example, if a fence panel is cut into two or more independent panels it can, in some circumstances, be difficult to join to form a unitary panel. In particularly instances the join can be readily interfered with and possibly be bulky and unsightly to the eye.

A different problem with which the present invention is concerned relates to the provision of barriers and deterrents to discourage a person from scaling a fence wall. Typical deterrents used with mesh wire fencing, for example, may include over-hanging posts between which barbed wire extends to make climbing difficult. These types of deterrents are typically unsightly to the eye.

Throughout this specification the use of the word "inventor" in singular form may be taken as reference to one (singular) inventor or more than one (plural) inventor of the present invention. Furthermore, the discussion throughout this specification comes about due to the realisation of the inventor and/or the identification of certain related art problems by the inventor and, moreover, it is to be appreciated that any discussion of documents, devices, acts or knowledge in this specification is included to explain the context of the present invention. It should not be taken as an admission that any of the material forms a part of the prior art base or the common general knowledge in the relevant art in Australia, or elsewhere, on or before the priority date of the disclosure and claims herein.

SUMMARY OF INVENTION

It is an object of the embodiments described herein to overcome or alleviate at least one of the above noted drawbacks of related art systems or to at least provide the public with a useful alternative. In a first aspect of embodiments described herein there is provided an accessory for a fence panel, the accessory comprising: a body having a first element, a second element and a connection therebetween, the connection having a first connection member and a second connection member inclined relative thereto and defining a cavity therebetween. In another aspect of embodiments described herein there is provided an accessory for a fence, comprising: a first element adapted for connection to a structural portion of a fence; a second element comprising a plurality of protruding portions adapted for one or a combination of: anchoring the fence, and: deterring an intruder from breaching the fence.

In a further aspect of embodiments described herein there is provided a fence comprising a first fence panel and a second fence panel and connector therebetween, the connector having a first element thereof connected to the first fence panel and a second connector thereof connected to the second fence panel and a join between the first and second connectors comprising two relatively inclined portions.

In yet a further aspect of embodiments described herein there is provided fence comprising a first fence panel having fence deterrent structure connected to an terminating end of the first fence panel, the structure comprising a first connector connected to the terminating end, a join extending from the first connector to a portion having a plurality of protruding portions arranged to deter avoidance of the fence, wherein said join comprises two inclined portions.

In another embodiment there is provided a method of assembling a fence comprising providing an accessory having a first element and a second element with a connector therebetween, the connector having two inclined portions, resting a fence panel against one of the inclined portions and with the assistance thereof fixing the fence panel in position against said second element.

In another embodiment there is provided a method of assembling a fence comprising providing an accessory having a first element and a second element with a connector therebetween, the connector having two inclined portions, fixing the first element in concrete and fixing the fence panel in position against the first element.

In yet another embodiment there is provided a method of manufacturing a fence accessory comprising a plurality of protruding portions adapted to form one or a combination of an anchor and a deterrent for a fence, the method comprising the steps of: patterning a symmetric profile of the protruding portions in a piece of material; making a single cut along the patterned symmetric profile to form at least two edges of protruding portions for providing at least two fence accessories.

In essence, embodiments of the present invention stem from the realisation that the unitary formation of a deterrent railing comprising at least one element adapted for connection to a fence structure such as a fence panel can provide directionally selective structural integrity as well as security to a fence whilst obviating the need for heavy gauge railing to provide joins for a fence.

Other aspects and preferred aspects are disclosed in the specification and/or defined in the appended claims, forming a part of the description of the invention.

As will be discussed embodiments of the present invention, advantageously provide an accessory for joining two fence panels. Advantageously the embodiments: (i) limit the use of the accessory for the purpose of scaling a fence; (ii) provides a strong join that cannot be readily bent; (iii) limits the bulk of the join; (iv) serves to space a number of fencing panels; and (v) is able to be formed by bending and cutting a single sheet of material.

Still further embodiments provide an accessory for use as a deterrent on a fence. The embodiments advantageously: (i) limit the use of the accessory for the purpose of scaling a fence; (ii) deters avoidance of the fence by burrowing underneath; (iii) provides a strong join that cannot be readily bent by hand; (iv) limits the bulk of the deterrent; and (v) is able to be formed by bending and cutting a single sheet of material.

Further advantages and scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

Further disclosure, objects, advantages and aspects of the present application may be better understood by those skilled in the relevant art by reference to the following description of preferred embodiments taken in conjunction with the accompanying drawings, which are given by way of illustration only, and thus are not limitative of the present invention, and in which:

Figure 1 is a perspective view an accessory according to a first preferred embodiment according to the present invention

Figure 2 is a sectional side view of the accessory shown in Figure 1 ;

Figure 3 is a sectional side view of another embodiment of the present invention;

Figure 4 is a front schematic view of a further embodiment of the present invention;

Figure 5 is a perspective view of yet another embodiment;

Figure 6 provides a sectional side view of the embodiment shown in Figure 5 and a sectional side view of another embodiment;

Figure 7 is a perspective view of an accessory according to a further embodiment;

Figure 8 is a plan view of the accessory shown in Figure 7 with the accessory joining two panels;

Figures 9 and 10 are sectional side views of the accessory shown in Figure 7; Figure 11 is a sectional side view of yet another embodiment;

Figure 12 is a sectional side view of yet another embodiment; and

Figure 13 is a schematic view of a further embodiment according to the present invention;

Figure 14 is a perspective view of a further embodiment including alternate profiles for the protruding portions;

Figure 15 is a side view of the embodiment of figure 14;

Figure 16 is a perspective view of yet another embodiment including alternate profiles for the protruding portions;

Figure 17 is a side view of the embodiment of figure 16. DETAILED DESCRIPTION

Referring to Figure 1 there is shown an accessory 10 according to a first preferred embodiment of the present invention. The accessory 10 provides enhanced rigidity to a flat mesh panel 12 and acts as a deterrent against a person attempting to use the accessory as a foot hold while further attempting to scale the flat mesh panel 12. The form and use of the accessory 10 is considered to be advantageous. With regard to "mesh" fencing, it is to be noted that the mesh is generally of metal wire that may coated or uncoated and may be formed to the fence by being welded, knitted or woven.

The accessory 10 comprises a body 14 having a first element 16, a second element 18 and a connection 20 therebetween. The connection 20, as shown in figure 1 , comprises a first connection member 22 and a second connection member 24 inclined relative to the first connection member 22. The first and second elements 16, 18 are provided with a cavity 26 therebetween and form a triangular cross-section having one side thereof removed. The connection 20 provides a resilient means.

As shown in Figure 2 the first element 16 and the second element 18 are substantially coplanar lying in the same plane 30. The first and second members 22, 24 are inclined relative to one another to provide resilience to bending in an outward perpendicular direction 32. This resilience serves to act against pushing or pulling of the mesh panel 12 or the accessory 10 in an attempt to damage the integrity thereof. The cavity 26 is directed away from the plane of the body 14. In cross-section, the first and second connection members 22, 24 form an isosceles triangle with the first and second elements, 16 and 18 respectively, extending in the plane of the base of the isosceles triangle, which corresponds to plane 30.

The first and second connection members 22, 24 are inclined at an angle that prevents an ordinary person from being able to secure a foot hold in the

cavity 26 when wearing shoes such as sneakers. In this embodiment the width 34 of the cavity 26 shown in Figure 1 is about 12 mm whilst the depth 33 of the cavity 26 shown in figure 2 is about 20mm. This equates to about a 34 degree inclination between the first and second connection members 22, 24. The accessory 10 may be formed from a single piece of steel, preferably of about 2mm in thickness that is bent to provide the connection 20. Notably, the thickness of the steel is chosen such that the thickness limits the ability of a person wearing sneakers from obtaining a foot hold on edge 33a of body 14 shown in Figure 1. As more clearly shown in Figure 2 the first and second connection members 22, 24 are of a triangular configuration 28 having a corner radius 36 of about 1mm at a relatively pointed end 38.

In this particular arrangement the first element 16 comprises a plurality of apertures 40 sized to receive a plurality of fasteners 42. When secured to the fence panel 12, at a terminating portion 44 of the fence panel 12, the second element 18 extends downwardly away from the fence panel 12. The second element 18 comprises a plurality of protruding portions 46 that have pointed ends configured to deter avoidance past the terminating portion 44.

With respect to the protruding portions as shown in the accompanying drawings, there are three preferred patterns described and which have been enumerated by the applicant, namely, "sierra" as shown in figure 1 , "pulse" shown for example throughout figures 18a to 18d and, "cupola". Each pattern may be provided in any embodiment as described herein.

As would now be apparent the accessory 10 is advantageous in that it serves to prevent or deter a person or other form of intruder from burrowing beneath the mesh panel 12. This is achieved by the combination of the protruding portions 46 and the configuration of body 14.

The outward resilience provided by stiffening in the correspondingly outward directions 32 away from the plane of the fence panel 12 advantageously limits the ability of the mesh to be pulled or pushed to create an arc in the lower edge 53 of the fence panel 12. Moreover, on expecting to have burrowed to a sufficient depth a person crawling underneath the panel 12 will be presented with pointed protruding portions 46. As mentioned above this serves as a deterrent.

As an example a person can be considered as attempting to burrow beneath the mesh panel 12 at location 48 shown in Figure 1. On pushing, pulling or kicking at location 50 to bend the lower edge of the mesh 12 the action of the person is met by resistance provided by the configuration of accessory 10. The person, tiring of the approach taken, consequently decides to remove a relatively large amount of earth at location 48. On having achieved this and on crawling underneath the mesh, the person is presented with the edges of the protruding portions 46 further deterring avoidance of the mesh. In another embodiment a concrete base beneath the protruding portion 46 may be used. In terms of the process of assembly of the accessory 10 to the mesh 12, the accessory of figure 1 provides a shoulder 52 against which lowermost portion of the fence panel 12 is able to rest to assist whilst attempting to align the apertures 40 and the mesh 12. This allows and/or assists persons assembling the fence to relatively position the accessory 10 and fix the fasteners 42 in place. Figure 3 shows another arrangement of accessory 10 used in conjunction with angle rail 54. The angle rail 54 is attached to an existing or specified fence (not shown). The angle rail may be a heavy duty angle rail considered suitable for use in cyclonic areas, a prison or to support a fence top structure such as an alarm system. Thus in the manner described the accessory advantageously provides stiffening to a flat mesh panel, which the mesh would not otherwise have, as well as providing a deterrent to discourage access underneath the fence panel.

With accessory 10 the angle and size of the first and second connection members 22, 24 can be modified along with the depth or/and material thickness depending on the rigidity required.

In another embodiment an accessory of the general form of accessory 10 is installed as a rail fixed to spaced apart fence posts supporting the mesh panel 12. The apertures 40 and fasteners 42 may also be used in this embodiment. . Referring to Figure 4 there are shown a number of exemplary projection profiles considered to be of advantage. The profiles symmetrically fit a corresponding mirror profile in which a preferred method of manufacturing the fence component allows for a single pass production step such as, for example, a laser cut to form the profiles. As shown in Figure 4 the symmetrical profile of the

protruding portions 46 is provided along two edges 56 with the spaces 58 between the protruding portions 46 having the same profile. Of course, the single laser cut may be formed by another cutting method in this manufacturing step.

Referring to Figures 5 and 6 there is shown a fence 60 according to a further embodiment of the present invention. The fence 60 comprises an accessory 63 having protruding portions 61 presented on an upper terminating end 62 of a fence panel 64. The accessory 63 comprises a cavity 65. The protruding portions 61 are presented in an upward direction to deter a person from avoiding the fence 60 by climbing over the upper terminating end 62 of the fence panel 64.

A person on attempting to scale the fence with sneakers is presented with the protruding portions 61 and is not able to gain a hand hold within the cavity 65. The walls of the accessory 63 forming the cavity 65 provide the accessory with advantageous bending resilience in a direction normal to the plane of the fence 60. Figure 6 also shows an embodiment in which an angle iron fence rail 64a is used.

Referring to Figure 7 there is shown an accessory 66 according to a third preferred embodiment of the present invention. The accessory 66 comprises a body 68 having a first flat planar element 70, a second flat planar element 72 and a connection 74 connecting the two elements 70, 72 therebetween. The accessory 66 and the connection 74 are symmetrical about plane 76 as shown in Figure 7. The connection 74 has a first connection member 78 and a second connection member 80 inclined relative to the first connection member 78 to provide a cavity 82. The first element 70 comprises a plurality of apertures 84 sized to receive a plurality of fasteners, 90 as shown in figure 8, to secure the first element 70 adjacent a terminating portion of a first fence panel, 98 as shown in figure 8. Similarly the second element 72 comprises a plurality of apertures 86 sized to receive fasteners, 102 as shown in figure 8', to secure the second element 72 adjacent a terminating portion, 100 as shown in figure 8, of another or second fence panel. In this manner the accessory 66 is adapted for use in forming a fence wall 92 comprising two or more panels or sub panels. This is shown in Figure 8.

The fence wall 92 is provided by a first fence wall panel 94 connected to a second wall panel 96 by the accessory 66. At a terminal end 98 of the first wall panel 94 a plurality of fasteners 90 extend through apertures 84 to secure the panel 94 to the first element 70 of accessory 66. At a terminal end 100 of the second wall panel 96 a plurality of fasteners 102 extend through the apertures 86 to secure the panel 96 to the second element 72.

With reference to Figure 9 it can be seen that the connection member 74 extends from one side of the two panels 94, 96 through to the opposite side. This advantageously reduces the ability of a person to use outer surface 75 of the connection member 74 as foot hold when trying to scale the fence wall. As with the previous embodiment the accessory 66 provides rigidity whilst not being bulky. This is achieved by virtue of the connection member 74 extending between both sides of the plane of the fence wall 92.

In the embodiment as shown in figure 9, the inclined members 78, 80 form a radiused bend 104 and are inclined at an acute angle of about 40 degrees relative to one another.

In Figure 10 it is shown that the first and second connection members 78,

80 are inclined to provide an outward triangular surface 106 directed in an opposite direction to the cavity 82. The first and second members 78, 80 extend about 22 mm away from the first and second elements 70, 72 and are inclined at an angle of less than about 60 degrees.

In a similar manner to the accessory 10 of figure 1 , described above, the accessory 66 is formed from a unitary piece of material bent to form the connection 74. The accessory 66 can be installed as either a rail fixed to posts at either end or attached only to the mesh itself as in retro-fitting.

Preferably the accessory 66 is located midway between the first and second panels 94, 96 to provide rigidity and the midway point of the fence wall panel 92. In another preferred embodiment 3000mm high and 2400mm high standard panels are stacked to provide for a 5400mm (approx) high fence (prison etc). The join occurs between the bottom 3000mm sheet and the 2400mm top sheet.

Referring to Figure 11 there is shown an accessory 124 according to another preferred embodiment of the present invention. In this embodiment the

angle formed by the connection piece is preferably about 25 to 35 degrees. With the associated dimensions shown in Figure 11 , 30 degrees is considered of benefit. The radius of the apex is about 1 mm. A further embodiment 107 is shown in Figure 12. Referring to Figure 13 there is shown a method of assembly

108 comprising providing an accessory 110 having a first element 112 and a second element 114 with a connector 116 therebetween, the connector 116 having two inclined portions 118. Following this a fence panel 120 is placed against one of the inclined portions 118 and fixed in position against said first element.

Advantageously and prior to this the second element 114 may be partially buried in a concrete length or kerb 117 to form a positive anchor to which the fence panel or mesh 120 is subsequently fixed. It is considered that with suitable fasteners, or otherwise as would be appreciated by the person skilled in the art, this advantageously overcomes the existing problem of corrosion in circumstances where the mesh is embedded directly in a concrete strip to provide security at the fence base. The accessory 110 may be advantageously galvanised or formed of rust resistant material. Various modifications to the above method are envisaged including an embodiment in which the second element 1 14 may be partially buried in concrete following attachment to the fence panel 120.

With reference to figure 14 there is shown an alternate embodiment of an accessory 200. In this embodiment, the first and second elements 210, 220 of the accessory are angled at 90 degrees for attachment to an existing fence top rail, for example, or alternatively this embodiment may be attached to a roof edge or wall top equally as to a fence structure. In figure 14 the top rail shown comprises angle rail 250 attached to the fence panel 212 by fasteners 242 through apertures 240 of the angle rail. Figure 15 shows this arrangement in a side view. Figure 14 also exhibits alternate patterns for the protruding portions 246.

Figure 16 shows an accessory for attachment to an angle rail as in figure 14 yet this time with a flat sheet formation for face attachment to the fence top rail or also bottom rail to act as a deterrent to getting under the fence. Similar

reference numerals as those used in figures 14 and 15 are used in figures 16 and 17. The flat formation for the accessory 200 is viable as a top or bottom fence deterrent particularly on a non-welded mesh fence such as a chain mesh/link fence as, like the fence, it is longitudinally flexible and does not attempt to give the fence horizontal stiffening but would provide the fence with vertical stiffening as additional support. Figure 17 provides a side view as figure 15

Given that the accessory may be horizontally neutral and chain mesh fences do not ordinarily have regulation bay widths, the accessory can be "lap ^* joined along a fence length regardless of where posts may be located. With reference to figures 18a to 18d, a method of attaching the above described embodiments of a fence accessory to fence posts and a post attachment assembly is described. The method of attachment to posts and the assembly described is particularly useful for attachment to hollow section type posts such as, for example, square hollow section (SHS) and rectangular hollow section (RHS) posts. The purpose of the attachment assembly or unit is to be able to secure the fence accessory preferably in the form of rolls to the posts of a fence at each end while enabling the roll top pattern of protruding portions to continue over the top of the post section in a unifolm manner.

In the preferred embodiments as shown in figures 18a to 18d, a post attachment assembly indicated generally at 333 is suitable for use in a fence. The attachment assembly ^' 333 comprises a first attachment element 311 and a second attachment element 312.

The first attachment element 311 has a first fastening means 301 for fastening the first attachment element 311 to a post, generally indicated at 306. A second fastening means 302 is provided for fastening the first attachment element 311 to at least one accessory 10 as shown in figures 18a to 18c and further described hereinabove. A plurality of protruding portions 334 is provided on the first attachment element 311 and these are configured to deter scaling of the post. When a post 306 is used to join, for example, two fence sections on a level site the protruding portions 334 are disposed for alignment with protruding portions of an accessory 10 which is substantially level with the top of the post 306.

As shown in figures 18b and 18c, the second fastening means 302 may be disposed to one side of the first attachment element 311 and adapted for fastening the first attachment element 311 to a single accessory 10 as shown most clearly in figure 18b at the top of the post 306. Alternatively, the second fastening means 302 may be disposed on two sides of the first attachment element 311 and adapted for fastening the first attachment element 311 to two accessories 10 as shown in figure 18a.

In the case of the need for attaching a lower section of a stepped fence, a second attachment element 312 is provided where, the second attachment element 312 has a third fastening means 303 for fastening the second attachment element 312 to a post 306; and fourth fastening means 304 for fastening the second attachment element 312 to at least one accessory 10 as shown and wherein the second attachment element 312 is adapted to be fastened to a post 306 below its top. The fastening means described with respect to figures 18a to 18d are preferably aperture means for receiving a fastener that joins the attachment elements to the post and accessory, respectively.

With the two forms of the first attachment element 311 in which the second fastening means 302 is disposed either on one or two sides thereof and the second attachment element 312, it is possible to provide three forms of post attachment. This may preferably be given in the form of three types of fish plate, as shown in figures 18a to 18c. Effectively, the embodiment of figure 18a provides a double sided attachment with provisions for continuing a fence pattern top for when the fence is on a level site. The alternate form of the first attachment element 311 as shown in figures 18b and 18c, provides a single sided (and also reversible) pattern top for the uppermost section of a stepped fence or for fence end/termination posts. The second attachment element 312 as shown in figures 18b and 18c provides a single sided fish plate for the lower section of a stepped fence. All three types of fish plates are preferably made from about 3 or about 6mm flat plate with the top pattern to suite the rails.

With regard to the embodiments described above it will be seen that the present invention provides at least the following advantages: (i) a deterrent and barrier to hinder access underneath a fence panel; (ii) stiffening to a flat mesh

panel to give mid height rigidity without offering an obvious foot hold; (iii) a way of joining two sections of mesh on the same plane without overlapping; (iv) stiffening to a flat mesh panel without the necessity of another form of device to give mid height rigidity and without offering an obvious foot hold; (v) provides an arrangement that can be installed as a stand-alone unit or incorporated as an addition to another section such as an angle rail.

In other embodiments the mesh panels have ribs or folds pressed into them for horizontal strengthening. Also the spikes could be cut as a hook or crescent shape and twisted or deformed laterally to point towards the attack side that is the side over which the fence would be scaled.

Head shape can be varied to suit required level of deterrent and/or manipulated after forming with twists or bends to align the angle to or from the perceived attack direction.

With the above description of embodiments in mind, the accessory of the preferred embodiments can, in conclusion, provide the following applications.

As a bottom fence formation, the preferred embodiments of the accessory may provide stiffening to a flat mesh panel that has no other form of device to give rigidity; provide a deterrent/barrier to hinder/discourage access under the - fence panel. Head shape can be varied to suit required level of deterrent and/or manipulated after forming with twists or bends to align the angle to or from the perceived attack direction as noted above. Depending on the stiffness required, the angle and depth and/or material thickness can be modified to suit. The accessory may be installed as a stand-alone unit or incorporated with another section such as an angie rail as noted above. It can be installed as either a rail fixed to the posts at either end or attached only to the mesh itself as in retro-fitting as noted above. It can be partially buried in the concrete kerb to form a positive anchor to which the mesh is attached as noted above. This overcomes the existing problem of corrosion to the mesh when embedded in the concrete strip to provide security at the fence base. As a mid rail formation for a fence, the preferred embodiments of the accessory provide stiffening to a flat mesh panel that has no other form of device to give mid height rigidity without offering an obvious foot hold. It may be installed

as either a rail fixed to the posts at either end or attached only to the mesh itself as in retro-fitting.

As a horizontal or vertical mesh joining device the preferred embodiments of the accessory provide a way of joining two sections of mesh on the same plane without the sections overlapping and the accessory also offers a degree of stiffening at the join and without offering an obvious foot hold. It can be installed as either a rail fixed to the posts at either end or attached only to the mesh itself as in retro-fitting.

As a fence topping rail, the preferred embodiments of the accessory provide stiffening to a flat mesh panel that has no other form of device to give rigidity. It provides a deterrent/barrier to hinder/discourage access over the fence panel. The head shape can be varied to suit required level of deterrent and/or manipulated after forming with twists or bends to align the angle to or from the perceived attract direction, as noted above. Depending on the stiffness required, the accessory angle and depth or/and material thickness can be modified to suit. It can be installed as a stand-alone unit or incorporated as an addition to another section such as an angle rail, as noted above. It can be installed as either a rail fixed to the posts at either end or attached only to the mesh itself as in retrofitting. While this invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modification(s). This application is intended to cover any variations uses or adaptations of the invention following in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth.

As the present invention may be embodied in several forms without departing from the spirit of the essential characteristics of the invention, it should be understood that the above described embodiments are not to limit the present invention unless otherwise specified, but rather should be construed broadly within the spirit and scope of the invention as defined in the appended claims. The described embodiments are to be considered in all respects as illustrative only and not restrictive.

Various modifications and equivalent arrangements are intended to be included within the spirit and scope of the invention and appended claims. Therefore, the specific embodiments are to be understood to be illustrative of the many ways in which the principles of the present invention may be practiced. In the following claims, means-plus-function clauses are intended to cover structures as performing the defined function and not only structural equivalents, but also equivalent structures. For example, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface to secure wooden parts together, in the environment of fastening wooden parts, a nail and a screw are equivalent structures.

"Comprises/comprising" when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof." Thus, unless the context clearly requires otherwise, throughout the description and the claims, the words 'comprise', 'comprising', and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to".