AU2003100651A4 - Vineyard netting post cap - Google Patents

Description

Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A INNOVATION PATENT

ORIGINAL

Name of Applicant: Actual Inventor: Address for Service: F F SEELEY NOMINEES PTY LTD Robert Wilton JAMES F F Seeley Nominees Pty Ltd P O Box 140 Melrose Park South Australia 5039 Attention: Intellectual Property Invention Title: "VINEYARD NETTING POST CAP" Details of Associated Provisional Application No: 2002951959 dated 10th October, 2002 The following statement is a full description of this invention, including the best method of performing it known to the applicant.

-1- Field of the Invention This invention relates to a cap to be fitted to a post, which is capable of supporting wires and netting such as bird netting.

Description of the Prior Art Throughout this description and the claims which follow, unless the context requires otherwise, the word "comprise', or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge in Australia.

It is common practice in the field of viticulture, and many fruit growing industries, to train vines and plants along wires suspended between lines of posts set into the ground. Such posts may take the form of round timber posts or may be formed from a variety of metal or plastic sections. The trellis so formed allows the plants to be grown in neat rows which are readily accessible for pruning, spraying, weed control and the many other maintenance tasks needed to keep the orchard or vineyard productive.

When the fruit or grapes grown by this method are ripening, the fruit is subject to predation from wild birds. This predation can devastate crops if steps are not taken to discourage the birds. An established method of keeping bird attacks under check is to cover the vines or plants with netting of a form which will not allow the birds to pass through. This netting must also be of a form such that it can be readily fitted over the orchard or vineyard as the fruit ripens, and be easy to remove, without damage, to allow picking of the fruit and plant maintenance procedures after the fruit is picked.

One method of fitting netting over the trellises formed by this method of horticulture is to fasten simple extension posts to the main posts supporting the trellis wires. These extension posts then support additional trellis wires, which, in turn, support the netting laid over the top of the plants without the netting becoming entangled in the plants it is protecting. Alternatively, the main trellis posts may be of a height greater than that needed for support of the growing plants, the excess height being used to support wires for the support of the netting.

When this method of support of the netting is adopted, it is essential that the netting be protected from the relatively sharp edges of the posts. The netting is fragile and can be easily damaged if it becomes caught on the posts during application or removal, or when moved by wind and rain while in service. The protection of the netting from the posts is generally by means of a cap fitted to the top of the posts, such as has been described in AU 746624 and AU 200177376. Both of these prior art documents describe post cap devices designed to fit to custom section shapes of posts used to form trellises, and which have a generally domed head which overlies the end the post to which it is attached. The devices described in both documents also rely on a hollow section formed in the underside of the post cap to provide grip between the post and the cap.

It is desirable to use inexpensive rolled steel sections when manufacturing the extension posts to support the additional trellising for the bird netting support. Since large numbers of these extension posts are needed for an orchard or vineyard, such simple sections as angles or circular tubes significantly reduce the costs of manufacture. The use of these extension posts also makes the installation and removal of the extensions relatively simple, thereby allowing machine access to the orchard or vineyard for pruning and other maintenance.

It is also desirable to support the top trellis wire of the extension trellis as high as possible, and preferably on the top of the post cap, in order to reduce as far as practicable any possibility of the netting tearing on the post or cap.

The prior art devices referenced above can only be used on the customised post sections for which they are designed. They are not suitable for a range of post cross sections or for use on simple post cross sections such as angles or tubes. Furthermore, none of the prior art devices provide for support of the trellis wires at the top of the post cap or for support of the trellis wires within the post cap itself.

The current invention addresses these deficiencies in the prior art devices. This is achieved by a design of post cap that allows simple and firmly retained fitment to a wide range of angle steel section extension or main posts. The design also allows for a limited range of metal or plastic annular circular or hollow square section posts to be fitted with the post cap.

Furthermore, the inclusion of mutually orthogonal slots and retaining clips in the top surface of the post cap allows the top row of trellis wire to pass across the top of the cap, providing maximum separation between the netting and post and post cap.

Summary of the Invention In one aspect the present invention provides a cap for an end of a post, said cap having a generally domed head of an overall dimension greater than the cross section of the post, post engagement means on the underside of the head, said engagement means including a central spigot projecting axially of the underside of the head and a plurality of peripheral spigots radially separated from the central spigot, wherein the separation between the central and peripheral spigots is such as to provide an interference fit of the engagement means to the post.

In a further embodiment of the invention, the post cap has at least one diametric slot through the dome shaped head, said diametric slot being positioned such that the linear direction of the at least one diametric slot is slightly out of alignment with the post line when the post cap is installed on a post of a line of posts. Preferably, concurrent with the at least one diametric slot, at least one clip is positioned to be in alignment with the post line, to retain a trellis wire in position once fitted to the slot in the cap.

Brief Description of the Drawings This invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a top perspective view of an embodiment of a post cap in accordance with the present invention; Figure 2 is a bottom perspective view of the post cap of Figure 1; Figure 3 is a side view of the post cap of Figure 1, mounted on a steel angle section extension post, and with a trellis support wire fitted; Figure 4 is a top perspective view of the post cap of Figure 1 mounted on a steel angle section extension post, and with a trellis support wire fitted.

Figure 5 is an inverse plan view showing the underside of the post cap of Figure 1 with a steel angle section extension post fitted; Figure 6 is a top view of the post cap showing the positioning of a trellis wire during and after installation; and Figure 7 is a side view of the post cap of Figure 6.

Description of Embodiments Referring to Figure 1, the upper surfaces of post cap 10 are shown where the post cap has been formed as a single piece plastic moulding. The upper surfaces incorporate the features of a generally domed upper surface 11, a tapered side relief 12, mutually orthogonal openings 13 to allow for the passage of the upper trellis wire and retaining clips 14 to hold the trellis wire in place once installed.

Figure 2 shows the post cap from a bottom perspective, in which the features required to retain the post cap 10 to the extension post are illustrated. When installed on an extension post, with the extension post being in the form of a steel angle section, the cap is retained between the four section star shaped centre brace or spigot 15 and any two of the flat sided edge braces or peripheral spigots 16. The clearance distances between the centre brace 15 and edge braces 16 are such that material thickness of the steel angle extension post becomes firmly wedged between the centre brace or spigot 15 and edge brace or spigot 16 when the post cap 10 is installed on the extension post in any of the four possible orientations of the extension post.

Figures 3 and 4 show a side and perspective view of the post cap installed on a steel angle section extension post 20. These views further show the upper trellis wire 30 installed on the post cap 10, through the trellis wire openings 13 and retained by the wire retention clips 14. The upper generally domed surface 11 which directly supports the bird netting (not shown) is apparent, together with the tapered side relief 12 shaped such as to prevent the catching of the bird netting when it is removed at the end of the season.

The trellis wire openings 13 are of a dimension such as to allow easy fitment through the slotted section of opening 13. The wire is then positioned beneath the retaining clip 14 on each side of the post cap 10 by manual placement of the wire. The retaining clips 14 will then retain the trellis wire within the post cap 10, in particular during period of high winds acting on the birdnetting retained by trellis wires 30. The trellis wires 30 can be easily removed as required by manually positioning the wire on each side of the post cap away from the underside of clip 14, and allowing the wire to pass up through the slotted section of opening 13.

Figure 5 shows an underside view of the post cap 10 when fitted to a steel angle section extension post 20. The post cap 10 is held in position on the extension post 20 by the centre brace 15 and edge braces 16. Centre brace 15 is shaped in the form of a cross, while the four side braces 16 are positioned such as to bear on the flat sides of the steel angle extension post 20. The position and dimensions of centre brace 15 and edge braces 16 are such that the extension post is a firm interference fit between the centre brace and the relevant pair of edge braces 16. When the post cap 10 is fitted to the extension post 20, and firmly driven onto the extension post 20 as far as it can go, the post cap 10 will be held onto the extension post 20 with considerable friction and will require considerable force to remove it again.

It is apparent that the fit of the post cap 10 to steel angle section extension post 20 is dependant solely upon the thickness dimension of the steel angle section and the corresponding dimension between the corners of the centre brace 15 and edge braces 16. For example, if the steel angle section is of 3 mm material thickness, then it will firmly fit into a post cap where the dimension between the centre brace 16 and edge brace 16 is sufficiently less than 3 mm such as to provide a firm interference fit while still enabling assembly. In particular, the fitment of the post cap 10 to the steel angle section 20 is not dependant upon the lengths of the sides of the steel angle section. The post cap 10 is capable of protecting the bird netting from damage from all sizes of steel angle section extension posts provided that the steel angle section does not protrude beyond the outer dimension of the post cap defined by the tapered side relief 12 portion of the post cap. The smallest dimension of the steel angle section which can support the post cap is determined by the position of the ends of the star shaped legs of centre brace relative to the edge braces 16. The smallest dimension of steel angle section which can be accommodated by the post cap is of little practical consequence, since such a small dimension post would not fulfil other strength and support criteria within the vineyard environment.

The post cap would normally be manufactured such that it can be fitted in any of the four available orientations to the steel angle extension post. This is achieved by designing the post cap such that all four orientations are identical, and the detailed gripping features on the underside of the post cap are symmetrical about the centre axis of the post cap. Those skilled in the art will recognise that the gripping details on the underside of the post cap do not need to be symmetrical, and that the gripping dimensions between the centre brace or spigot and edge braces or spigots could readily accommodate two different material thicknesses of the steel angle section. This could be achieved by making the gripping dimension between any two adjacent edge grips a first gripping dimension, and the gripping dimension between the remaining two adjacent edge grips a second gripping dimension. The same post cap could then be fitted to either thickness of steel angle section without modification.

It will also be recognised by those skilled in the art that the post cap could also be fitted to a tubular, circular section post whereby the inner radial dimension of the circular section was a firm fit over the extremities of the centre brace 15. Similarly, it will be recognised that the post cap could also be fitted over a tubular, square section post whereby the material thickness of the square section post provides a firm fit between the centre brace 15 and edge braces 16, and the outer dimension of the square section post fits between the faces of opposite edge braces 16. When the post cap design is adapted to fit a circular or square shaped post, it must be dimensioned for a specific size of extension post section. While the post cap can only be used for this specific size of circular or square section extension post, it can still accommodate any dimension of steel angle extension post of the specific material thickness.

The fitment of the trellis wire to the post caps is further illustrated in Figures 6 and 7. In Figure 6, the location and shape of the trellis wire while it is being fitted to the post cap is shown as 31. The wire attains shape 31 by manually fitting the wire into the slot 13 after the post cap 10 has been fitted to the extension post 20. When the post cap 10 has been fitted to extension post 20, the slot 13 which is generally in the direction of the trellis wires will have an alignment which is a small angle different to the trellis wire alignment.

To fit the trellis wire through slot 13 will therefore require distortion of the wire to the shape shown as 31.

Once the trellis wire has been distorted to shape 31 and fitted to the slots 13, it is released from its distorted shape. The trellis wire will then revert back to its undistorted alignment along the post line. When the trellis wire has sprung back to its preferred alignment illustrated as position 30, while in the bottom of slot 13, the position of the wire will then be underneath the clip 14 of the post cap. The alignment of the passage beneath diametrically opposite clips 14 is aligned or closely parallel to the trellis wire alignment once the post cap is fitted to the extension post. Since this alignment is the preferred alignment of the trellis wire, and additional force and energy is required to distort the wire back to the slots 13, then there is little tendency for the wire to become released from beneath clips 14 once positioned there. It will be appreciated that once a row of post caps on extension posts are fitted with trellis wire as described, the trellis wire will be firmly retained in position until deliberately removed at the end of the season.

The extension post can be made of a variety of materials, including rolled steel, formed sheet steel or plastic without detracting from the performance or function of a post cap in accordance with the present invention.

Claims (4)

1. A cap for an end of a post, said cap having a generally domed head of an overall dimension greater than the cross section of the post, post engagement means on the underside of the head, said engagement means including a central spigot projecting axially of the underside of the head and a plurality of peripheral spigots radially separated from the central spigot, wherein the separation between the central and peripheral spigots is such as to provide an interference fit of the engagement means to the post.

2. A cap for an end of a post as claimed in claim 1 wherein the post cap includes at least one diametric slot across the dome shaped head, said diametric slot being positioned such that the linear direction of the at least one slot is slightly out of alignment with the post line when the post cap is installed on a post of a line of posts.

3. A cap for an end of a post as claimed in claim 2 wherein said at least one diametric slot includes at least one clip positioned to be in alignment with the post line, said clip functioning to retain a trellis wire in position once fitted.

4. A cap for an end post as claimed in claim 1 or 2 which includes a plurality of diametric slots wherein each slot is provided with a clip at diametrically opposed extremities of the slot. A cap for an end post substantially as hereinbefore described with reference to the accompanying drawings. TED this 8t h day of August, 2003 W James for and on behalf of F F SEELEY NOMINEES PTY LTD