AU2017101545A4 - Ground Anchor - Google Patents

Abstract

A ground anchor is shown comprising a rotatable shaft 10 having a longitudinal axis A, an upper end 1 Oa, and intermediate section 1 Ob, and a lower portion 1 Oc, ending in a terminal end of the shaft 10. The ground anchor also comprises an auger 11 5 mounted to the lower portion 1Oc; a cutting tip 12 mounted to the terminal end; a plurality of radial fins 9 mounted around the intermediate section 1 Ob, the shaft 10 being adapted to rotate relative to the fins 9; a top plate 3, 30 mounted to the upper end 1 Oa and adapted to couple a linkage to a building structure; and a drive coupling 1 adapted to connect a drive means. Each fin 9 is preferably substantially planar and 0 comprises no gussets or fold lines extending parallel to the longitudinal axis A. Figure 1 -44

Description

GROUND ANCHOR

FIELD OF INVENTION

This invention relates to a ground anchor. More particularly, this invention relates to a ground anchor for bracing building panels during building construction.

BACKGROUND ART

The following references to and descriptions of prior proposals or products are not intended to be, and are not to be construed as, statements or admissions of common general knowledge in the art. In particular, the following prior art discussion should not be assumed to relate to what is commonly or well known by the person skilled in the art, but to assist in the inventive process undertaken by the inventor(s) and in the understanding of the invention.

Ground anchors generally comprise a spiral auger blade and a cutting tip mounted to a terminal end of a shaft, and a plurality of radial fins intermediate the length of the shaft, and a top mounting plate. The fins typically extend in planes parallel to the longitudinal axis of the shaft and serve to prevent rotation of the plate, thereby providing non-rotating elements. Prior art attempts include fins that have folds or gussets for increased rigidity. However, this increases manufacturing costs, increases the force required for entry and retraction of the ground anchor relative to the ground, and does not materially increase the fins performance in resisting lateral forces transmitted through the mounting plate and the shaft.

An object of the present invention is to ameliorate the aforementioned disadvantages of the prior art or to at least provide a useful alternative thereto.

STATEMENT OF INVENTION

The invention according to one or more aspects is as defined in the independent claims. Some optional and/or preferred features of the invention are defined in the dependent claims.

Accordingly, in one aspect of the invention there is provided: a ground anchor comprising: a rotatable shaft having longitudinal axis, an upper end, an intermediate section, and a lower portion ending in a terminal end of the shaft; an auger mounted to the lower portion; a cutting tip mounted to the terminal end; a plurality of radial fins mounted around the intermediate section, the shaft being adapted to rotate relative to the fms; a top plate mounted to the upper end and adapted to couple a linkage to a building structure; and a drive coupling adapted to connect to a drive means, wherein: the top plate comprises an array of mounting points, each mounting point for attaching to one of said linkages; the mounting points are radially spaced from, and arranged around, the longitudinal axis; irrespective of its orientation, the top plate 3 is adapted to present a pair of the spaced mounting points 3bi,bii which are aligned in a plane substantially normal to the direction in which the linkages extend.

GROUND ANCHOR

The ground anchor is most suitable to provide an anchor in penetrable ground, such as soil or clay, to support and anchor building structures, such as wall panels. The building structure may be linked to the anchor using a bracing rod or beam capable of resisting axial compression forces. Alternatively, the link extending between the anchor and the building structure may comprise one or more tension cables. The anchor is preferably capable of securing heavy loads, noting that the range of securable loads varies depending on ground types and the load rating applicable to each particular ground anchor.

SHAFT

The shaft is preferably externally circular in section. The shaft may be a solid tube or may be cylindrical. The shaft may be substantially consistent in cross-section substantially throughout the length of the shaft. The shaft is rotatable about the longitudinal axis. The shaft is fixedly connected to the drive coupling. The shaft is fixedly connected to the auger and the tip. The fms are rotatably mounted on the shaft whereby the fms are adapted be non-rotatable whilst the shaft rotates.

TIP

The cutting tip may comprise one or more teeth extending from a base mounted to the terminal end. Preferably, the tip comprises a pair of radially spaced tooth tips. Optionally, the tip may include a single centring and axially aligned spike. The pair of spaced teeth may be formed from a single plate cut and folded to form a short double helix terminating in a pair of downwardly pointing barbs or spikes. The teeth may taper inwardly from the base top the barbs or spikes.

AUGER

The auger may be in the form of a spiral blade. The auger may consist of a single spiral blade. The blade may be mounted to the external surface of the shaft. The blade may be welded to the shaft. The blade may have a substantially circular footprint when view along an axial line. However, the blade may comprise straight edges. The blade may include rounded or bevelled comer sections. The blade may include N + 1 straight edges extending between N rounded comers, where N is the number of comers. The blade may terminate at a location on the shaft at or near the base of the cutting tip. The blade may wrap around the lower portion and have upper and lower terminal edges. The terminal edges may comprise flat edges. The terminal edges may be aligned substantially radially relative to the longitudinal axis. In axial view, the upper terminal edge of the blade may be spaced from the lower terminal edge by a radially aligned gap.

FINS

The radial fins may comprise 2, 3, 4 or more axially parallel aligned blades.

Preferably, the radial fins comprise a set of fins arranged in plan to form a cross or an “X”. The fins may comprise two pairs of fins, each member of each pair lying in a plane inclined at an acute angle relative to a plane in which the other member of the pair lies. Adjacent fins belonging to different pairs may lie in respective planes that are inclined at an obtuse angle. Preferably, the fins are each set at right angles relative to the adjacent fins and opposed fins lie in the same plane. In any case, irrespective of the final orientation of the fins relative to a plane of the building structure that the anchor is intended to support, the same amount of resistance to lateral forces in a certain direction is provided collectively by a set of four fins. The sum of the surface area opposing such lateral forces remains the same. An increase in the obtuse nature of the angle of inclination of one of the fins to the plane of a building structure will result in an equal and corresponding decrease in the acute nature of the angle of inclination of another one of the fins to the plane of a building structure because each fin belongs to a pair of fins set at an angle, preferably a right angle, or coplanar, relative to each other.

Each fin may be substantially planar. Each fin may have no gussets or fold lines extending parallel to a longitudinal axis of the shaft. The radial fins are preferably substantially identical to one another. The radial fins advantageously taper downwardly along a tapered outer edge towards the intermediate section of the shaft. The tapered outer edge of the radial fin may terminate in a small radially aligned flat portion at its lower most point. The tapered outer edge is adapted to facilitate entry of the radial fin into the ground by presenting an inclined edge.

The radial fins are mounted to the shaft by at least one coaxial tube bearing. The tube bearing forms a sleeve about the intermediate section. The upper portion of the radial fin may be attached to a lower surface of the mounting plate. The upper portion of the radial fin may comprise at least one tab extending through the lower surface of the mounting plate. The tab may be received in a radially aligned slot or recess formed in the mounting plate.

PLATE

The top plate is adapted to receive or engage with a complementary coupling to couple a linkage to building structure using the mounting points. The mounting points may be hooks, eyelets, apertures or other structures that enable a hook, bolt or grasping element to engage therewith. Preferably, the mounting points each comprise an aperture. The apertures may be adapted to receive a bolt. Each of the apertures may be internally threaded to threadably receive the threaded shaft of a bolt. The apertures may each comprise a through bore to receive a bolt and nut attachment.

The top plate is preferably adapted to be oriented in any position through 360° of rotation of the ground anchor. Therefore, a second operator in addition to a first operator being a PTO device driver is not required to orientate the top plate relative to the intended building structure. Such a second operator is therefore not exposed to the dangers of the rotating anchor kicking or jerking as the auger is being driven into the ground. The effect of a rotating anchor kicking or jerking whilst large rotational forces are applied by a PTO, etc. has the potential to cause an injury to the operator’s arm or shoulder.

The top plate may be generally planar. The top plate may present substantially planar upper and lower surfaces. As previously described, the underside surface of the top plate may include slots or other recesses to receive a tab or other portion of an upper end of a fin.

The top plate may include a plurality of apertures whereby to receive fasteners, such as bolts extending through the linkage coupling and the top plate to secure the linkage coupling in place once the ground anchor has been installed at its desired location in the ground. The top plate may be any one of a variety of shapes, including polygonal, round and square. The top plate is preferably formed from mild steel plating that may be, for example, depending on the application and the expected actual and vertical loads, between 8-16mm. Other materials, particularly metal alloys, contemplated as being within the scope of the invention.

DRIVE COUPLING

The drive coupling may be in the form of a mounting disk or block and be adapted to receive the coupling end of a drive means, such as a power take off (PTO).

The drive coupling may be shaped to receive a square-ended drive means. The drive coupling is advantageously directly rotatable with the drive shaft to rotate the auger and cutting tip, whilst the radial fins remain rotationally static.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be better understood from the following non-limiting description of preferred embodiments, in which:

Figure 1 is an exploded asymmetric view of a ground anchor according to one embodiment of invention;

Figure 2a is an asymmetric view of the drive assembly of the first embodiment shown in Figure 1;

Figure 2b is a side elevation of the drive assembly shown in Figure 2a;

Figure 2c is a magnified side view of the drive coupling shown in Figure 2b;

Figure 3 is an asymmetric view of the static assembly of the top plate and radial fins of the first embodiment;

Figures 4a-c are various isometric and side and top plan elevation views of the first embodiment;

Figure 4d is a magnified view of the upper portion of the drive assembly shown in Figure 4c;

Figures 5a-e are various top, end and side elevations, and isometric views of the auger of the first embodiment;

Figure 6a-f are various asymmetric, and side and plan elevations of the cutting tip of the first embodiment shown in Figure 1;

Figures 7a-c are, respectively, plan and side elevations, and an asymmetric view, of an alternative second embodiment of the present invention; and

Figure 8 is a schematic view of the positioning of a pair of ground anchors made according to the first embodiment relative to the building structures.

DETAILED DESCRIPTION OF THE DRAWINGS

Preferred features of the present invention will now be described with particular reference to the accompanying drawings. However, it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the invention. A ground anchor is shown comprising a rotatable shaft 10 having a longitudinal axis A, an upper end 10a, and intermediate section 10b, and a lower portion 10c, ending in a terminal end of the shaft 10. The ground anchor also comprises an auger 11 mounted to the lower portion 10c; a cutting tip 12 mounted to the terminal end; a plurality of radial fins 9 mounted around the intermediate section 10b, the shaft 10 being adapted to rotate relative to the fins 9; a top plate 3, 30 mounted to the upper end 10a and adapted to couple a linkage to a building structure; and a drive coupling 1 adapted to connect a drive means. Each fin 9 is preferably substantially planar and comprises no gussets or fold lines extending parallel to the longitudinal axis A.

Referring to Figure 1, there is shown a ground anchor according to a first embodiment of the invention. The ground anchor according to the first embodiment comprises a mounting disk 1 having an upwardly facing square or block recess la. The mounting disk 1 is preferably fixed to a push bearing 2 by welds. The push bearing 2 comprises a central aperture 2a adapted to receive an upper end 10a of a shaft 10. The upper end 10a does not fully extend through the aperture 2a, but only axially partially into the aperture 2a whereby to leave an upper space 2b in the upper end of the aperture 2a. The upper space 2b is adapted to provide space at the top of the shaft 10a to allow for a weld to join the push bearing 2 to the shaft 10. Once the weld in the space 2b is formed, it is preferably ground flat prior to welding the mounting disk 1 to the upper surface of the push bearing 2 as best shown in Figure 2c. A top plate 3 is adapted to be located in between the push bearing 2 and a pull bearing 5 on the upper end 10a of the shaft 10, but is not attached to the shaft 10. Rather, the top plate 3 “floats” and is axially trapped between the push bearing 2 and the pull bearing 5. The top plate includes a plurality of circumferentially spaced and radially equispaced apertures 3b each adapted to receive the shaft of a bolt (not shown) to which a nut 4 may be threadably engaged. This enables attachment of a linkage coupling (not shown) to the top plate 3 during use, following the installation of the ground anchor in a ground location.

The top plate 3 further includes radially equally spaced slots 4a that are adapted to receive an upper tab 9a of each radial fin 9, so that the radial fins 9 and the top plate 3 form part of a static assembly best shown in Figure 3. The spaced slots 4a number four and are aligned radially. However, the number of radial fins may determine how many slots 4a are required.

The radial fins 9 are rotatably mounted to the shaft 10 by a pair of sleeves in the form bearing tubes 6, 8. The bearing tubes 6, 8 are, in part, axially spaced by inner flanges 9c, d of the radial fins 9. The inner flanges 9c,d extend in the same plane as the substantially planar radial fin 9 but are radially spaced from the shaft 10 which is rotatable relative to the fms 9. A bottom stop 7 is adapted to be received within a recess defined by the lower flange 9c and the lower end 9g of the fin 9. The bottom stop 7 is fixed, for example, welded to an intermediate section 10b of the shaft 10 and correctly axially locates the sleeve-like bearing tubes 6,8 on the shaft 10.

The upper outer edge 9e of the radial fin 9 is adapted to extend substantially parallel to the longitudinal axis A of the shaft 10. A lower section of the outer edge tapers inwardly towards the axis A and terminates at the lower laterally extending short wall 9g. The radial fms 9 are fixedly attached to the top plate 3 and bearing tubes 6, 8 and this static assembly effectively rotatably “floats” relative to the shaft 10, whilst being axially trapped on the shaft 10. A spiral auger 11 is welded to the lower end 10c of the shaft 10. The auger blade is formed from a planar plate, laser cut and worked to bend the blade into a spiral shape, whereby the upper terminal end 1 la of the blade and lower terminal end 1 lb do not overlap when viewed in plan as shown in Figure 5a. The lower end 1 lb is bevelled on its upper side to form a cutting edge that displaces soil or other in-ground material into the vortex space 1 lc of the rotatable spiral blade 11. The blade 11 provides a relatively short rotational travel (less than 360°), such that the trailing of the blade lid provides less rotational resistance than a fuller blade might where the flight comprises more than one whole turn.

The auger blade 10 includes a combination of flattened outer edges lie and rounded comers 1 If therebetween, such that the generally square shape of the auger in plan (as shown in Figure 5) provides a more aggressive cutting edge.

Mounted to the terminal end of the shaft 10 is a tip mount disc 12 into or onto which is welded, or otherwise attached, a lower cutting tip 13 in form of a pair of barbs or teeth 13a. The teeth 13a are offset relative to each other either side of a vertical plane P that is aligned with the longitudinal axis A.

Referring to Figures 2a-c, and particularly Figure 2c showing detail a in Figure 2b, a sectional view shows the thickness of the shaft 10 wall lOd, with the inner wall surface shown in broken lines and the upper end lOe of the shaft 10 also shown in ghosted lines. The welding gap 2b is defined between the upper end lOe and the lower surface of the mounting disc 1, together with the entailed surface of push bearing to defining the aperture 2a.

The space 3a between the push bearing 2 and the pull bearing 5 enables the top plate 3 to be axially trapped therein, as shown in the detail of Figure 4d. As can be seen in Figure 4d, the inner flanges 9d,e are axially spaced from the external surface lOe of the shaft 10.

Referring to Figures 6a-f, it is noted that a base 13b of each of the teeth 13a lies centrally in the plane P, whereas the apices 13c of the teeth 13a are located outside the plane P. The angles theta and delta representing the angle of inclination of each tooth 13a relative to the base 13d and the plane P is about 15°-25°. The terminal edges 13c are inclined at the angle delta whereby the inner edge 13d of each tooth 13a cuts an initial small circular cut in the ground to break the surface and the successive new layers of ground material as the ground anchor bears down into the ground, and the wider leading terminal blade edge 13c cuts a wider circle, whilst the inclination of the leading edge 13c facilitates displacement of cut ground material radially outwardly to enable entry of the lower end 10c in the cavity so formed. The aggressive cutting blade shape of the auger 11, with comer portions 1 lb providing a more aggressive cut than a spiral blade with a circular shape, ensures an effective cutting device, even with the circumferentially shortened spiral blade. However, the shortened spiral blade 11 enables the auger 11 to be simply and efficiently formed from metal plate material as the pitch does not extend more than 360°.

With reference to Figures 7a-c, a similar arrangement is shown, with the exception that the top plate 30 is square-shaped in plan, rather than circular. In both cases, the first and second embodiments provide an extremely simple and efficiently manufactured mounting arrangement that avoids the complex mounting arrangements of known prior arrangements. The planar top plate 3, 30 is simply axially trapped between the upper push bearing 2 and the underside pull bearing 5 and attached to the radial fins 9 by receiving an upper tab 9a in the corresponding slots 34a of the top plate 30. The second embodiment includes only two radial fms 9 diametrically opposed relative to the shaft 10 and lying in the same plane as each other. An odd number of radial fins 9 is within the scope of this invention and merely requires that suitably radially and circumferentially spaced slots be formed in the top plate 3, 30.

Accordingly, the top plate 3, 30 is easy to manufacture and provides a simplified mounting assembly for coupling a linkage, wherein a corresponding mounting plate or (need only be provided to secure the linkage coupling to the drive means).

The building structure may be in the form of panels 15a,b. The panels 15a,b may be arranged to form corner wall sections or be coplanar as represented in Fig. 8. The inventive arrangement can comprise a single ground anchor 20, or multiple ground anchors 20a,b, to support a building structure 15. There may be one or more building structures 15 supported by one or more ground anchors 20.

The adjacent ground anchors 20a,b may be installed in the ground at spaced locations

According to one aspect of the invention and the method of installation, the rotational positioning of the fms 9 and the top plate 3 is not critical. The four fms 9 may be oriented at any position through 90 degrees or 360 degrees without materially affecting the way that the ground anchor 20a,b performs with regard to resistance to lateral forces.

The combined effective surface area Ai, Ai, Bi, B2, of the four fins 9 in the direction of the vector facing the panels 15a,b is substantially the same, irrespective of how the ground anchor 20a,b ends up being oriented relative to the panels 15a,b. This is schematically shown in Fig. 8, in which the left-hand side ground anchor 20a is installed in the ground without the guidance of a second operator. That is, no operator is required to ensure that the lower tips 9g of the fins 9 contact and enter the ground with the fms 9 or the apertures 3b in a particular orientation.

The combined effective surface area Ai, A2, Bi, B2, of the four fins 9 remains substantially constant as the top plate 3 rotates about the longitudinal axis A (noting such rotation is free-floating and not driven in association with the shaft’s 10 driven rotation). In the right hand ground anchor 20b, the resistive vector force applied by the various fin surfaces in the direction facing the building structures 15 diminishes for fms 9i,ii, but correspondingly increases for fms 9iii,iv. The sum total of resistive force applied by the fms to lateral forces imposed by the linkages 14 remains substantially consistent irrespective of the orientation of the ground anchor 20.

The shaft 10 and fins 9 are generally oriented so that the top plate 3 is parallel to the horizontal, and the fms 9 and the shaft 10 are substantially vertical. Alternatively, the top portion 10a of the shaft 10 is aligned to be spaced further from the building structure 15 than the lower portion 10c, so that the shaft 10 is closer to normal to the longitudinal axis of one or more of the linkages 14ai,aii,bi,bii. If the linkages 14 are not linear, but have a curved shape because, for example, they comprise tension cable, the shaft 10 is closer to normal to a straight line extending between the linkage coupling la and the mounting point 16 of the linkage 14 to the panel 15. However, the linkages are typically rigid in construction so that they resist both strong compression as well as tensile forces.

The fins 9 include a pair of fms 9i,ii and a second pair of fms 9iii,iv. The top plate 3 can be oriented in any direction through 360 degrees so that any one of the fms 9i-iv can be inclined at any angle to the building structure 15a,b and still be effective in resisting lateral forces applied by the building structure 15 via the linkage 14 to the ground anchor 20. The first pair of fms 9i,ii are aligned parallel with the panels 15a,b to ensure so that the top plate 3 is oriented with a pair of opposed fms 9i,ii aligned

Moreover, the top plate 3 contains a plurality of linkage mounting points in the form of the apertures 3b. The mounting points 3b are arranged in a circular array around the periphery or intermediate the radial extent of the top plate 3 whereby, irrespective of the orientation of the top plate 3, a pair of apertures 3b will be usable to attach one end of the linkage 14 to the top plate 3 at a point that faces the building structure 15 - in most cases this will be substantially normal to the building structure 15.

In Fig. 8, the linkages 14ai,aii are shown attached at mounting points 3bi,bii to the left hand side anchor 20a. For the right hand side anchor 20b, which is shown rotated about 50 - 60 degrees relative to the left anchor 20a, the most suitable mounting points for linkages 14bi,bii are apertures 3ci,cii. The combination of the array of apertures 3b and the quaternary of fins 9 allow the anchor 20 to be effective as a ground anchor in any rotational orientation.

Throughout the specification and claims the word “comprise” and its derivatives are intended to have an inclusive rather than exclusive meaning the contrary is expressly stated or the context requires otherwise. That is, the word “comprise” and its derivatives will be taken to indicate the inclusion of not only the listed components, steps or features that it directly references, but also other components, steps or features not specifically listed, unless the contrary is expressly stated or the context requires otherwise.

In the present specification, terms such as “apparatus”, “means”, “device” and “member” may refer to singular or plural items and are terms intended to refer to a set of properties, functions or characteristics performed by one or more items or components having one or more parts. It is envisaged that where an “apparatus”, “means”, “device” or “member” or similar term is described as being a unitary object, then a functionally equivalent object having multiple components is considered to fall within the scope of the term, and similarly, where an “apparatus”, “assembly”, “means”, “device” or “member” is described as having multiple components, a functionally equivalent but unitary object is also considered to fall within the scope of the term, unless the contrary is expressly stated or the context requires otherwise.

Orientational terms used in the specification and claims such as vertical, horizontal, top, bottom, upper and lower are to be interpreted as relational and are based on the premise that the component, item, article, apparatus, device or instrument will usually be considered in a particular orientation, typically with the linkage coupling uppermost.

It will be appreciated by those skilled in the art that many modifications and variations may be made to the methods of the invention described herein without departing from the spirit and scope of the invention.

Claims (5)

1. The Claims defining the invention are as follows:

   1. A ground anchor 20 is shown comprising a rotatable shaft 10 having a longitudinal axis A, an upper end 10a, and intermediate section 10b, and a lower portion 10c, ending in a terminal end of the shaft 10; an auger 11 mounted to the lower portion 10c; a cutting tip 12 mounted to the terminal end; a plurality of radial fins 9 mounted around the intermediate section 10b, the shaft 10 being adapted to rotate relative to the fins 9; a top plate 3 mounted to the upper end 10a and adapted to couple a linkage to a building structure; and a drive coupling 1 adapted to connect a drive means, wherein: the top plate 3comprises an array of mounting points 3b, each mounting point for attaching to one of said linkages 14; the mounting points are radially spaced from, and arranged around, the longitudinal axis A; irrespective of its orientation, the top plate 3 is adapted to present a pair of the spaced mounting points 3bi,bii which are aligned in a plane substantially normal to the direction in which the linkages extend.
2. 2. A ground anchor as defined in Claim 1, wherein the mounting plate 3, 30 comprises a single planar plate trapped between upper and lower push and pull bearings 2, 5 whereby to axially trap the top plate 3, 30 about the shaft 10.
3. 3. A ground anchor as defined in Claim 1 or 2, wherein the radial fin 9 comprises an upper tab extending proud of its upper edge, whereby the tab 9a is adapted to be received in a radially aligned slot 4a extending through the top plate 3.
4. 4. A ground anchor as defined in any one of Claims 1-3, wherein the radial fin 9 includes radially inwardly projecting inner flanges 9c, d that are respectively received in annular recesses defined between the pull bearing 5, and upper end lower bearing tubes 6, 8, to which the radial fins 9 are welded, such that the static assembly so formed rotatably floats relative to the shaft and is axially trapped relative to the shaft.
5. 5. A ground anchor as defined in any one of Claims 1-4, wherein the upper end 10a of the shaft 10 extends only partially through an aperture 2a formed in the push bearing 2, whereby to define a recess 2b within which welds can be formed between the shaft and the push bearing 2.