U.S. patent application number 11/910777 was filed with the patent office on 2008-08-21 for anchoring device.
Invention is credited to Fergus Johnathan Ardern.
Application Number | 20080196328 11/910777 |
Document ID | / |
Family ID | 34586747 |
Filed Date | 2008-08-21 |
United States Patent
Application |
20080196328 |
Kind Code |
A1 |
Ardern; Fergus Johnathan |
August 21, 2008 |
Anchoring Device
Abstract
An anchoring device comprising a shaft, at least part of whose
length comprises a tapered portion, with at least one helical
flange which runs substantially along the length of said tapered
section and an engagement means to allow the device to engage with
a lever wherein in use rotation of the lever about the axis of the
shaft results in rotation of the device such that the tapered
portion and the helical flange co-operate to drive the device into
the ground.
Inventors: |
Ardern; Fergus Johnathan;
(Norfolk, GB) |
Correspondence
Address: |
SYNNESTVEDT & LECHNER, LLP
1101 MARKET STREET, SUITE 2600
PHILADELPHIA
PA
19107-2950
US
|
Family ID: |
34586747 |
Appl. No.: |
11/910777 |
Filed: |
April 4, 2006 |
PCT Filed: |
April 4, 2006 |
PCT NO: |
PCT/GB2006/001237 |
371 Date: |
April 29, 2008 |
Current U.S.
Class: |
52/155 |
Current CPC
Class: |
E04H 12/2223
20130101 |
Class at
Publication: |
52/155 |
International
Class: |
E04H 12/22 20060101
E04H012/22 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 5, 2005 |
GB |
GB 0506909.1 |
Claims
1. An anchoring device comprising a shaft, at least part of whose
length comprises a first tapered portion, with at least one helical
flange which runs substantially along the length of said first
tapered portion and an engagement means to allow the device to
engage with a lever wherein in use rotation of the lever about the
axis of the shaft results in rotation of the device such that the
first tapered portion and the helical flange co-operate to drive
the device into the ground.
2. An anchoring device as claimed in claim 1 wherein the first
tapered portion occupies a majority of the length of the shaft.
3. An anchoring device according to claim 1 wherein the diameter of
the helical flange is uniform along the majority of the length of
the first tapered portion of the shaft.
4. An anchoring device according to claim 1 which further comprises
a plate positioned perpendicular to the length of the shaft at or
adjacent the end of the device distal from the said first tapered
portion.
5. An anchoring device according to claim 1 which further comprises
a masonry bit attached to the end of the shaft adjacent of said
first tapered portion.
6. An anchoring device according to claim 1 wherein the shaft
further comprises a second tapered portion proximal to the end of
the shaft distal to the first tapered portion wherein the
cross-section of the shaft increases in a direction away from the
first tapered portion of the shaft.
7. An anchoring device according to claim 1 wherein the shaft of
the device is hollow and further comprises a threaded section in
the hollow.
8. An anchoring device according to claim 1 wherein small
protrusions are present on the first tapered portion of the
shaft.
9. An anchoring device as claimed in claim 8 wherein the
protrusions are pyramidal.
10. An anchoring device according to claim 1 wherein the device is
colour coded.
12. An anchoring device according to claim 1 wherein the device
incorporates drainage holes to prevent the retention of water in
the hollow shaft and/or in the engagement means of the device.
13. (canceled)
Description
FIELD OF THE INVENTION
[0001] The present invention relates to ground anchors which are
generally elongate devices adapted to be inserted into the ground
in order to form an anchor point to which other items, such as sign
posts, flagpoles or the like can be attached.
PRIOR ART KNOWN TO THE APPLICANTS
[0002] One commonly known form of ground anchor comprises a hollow
post or hollow rod which is driven into the ground to an
appropriate depth. Anchor arms are then extended from the hollow
interior into the ground and act to stabilise the post or rod, see
GB2216915A. Normally this type of device is driven into the ground
using a mallet or the like.
[0003] PCT/GB94/00072 discloses a ground anchor for supporting
posts or other structures which comprises a tubular socket and a
twisted flat bar. In use, a hole is prepared into which the socket
is inserted. The end of the bar is then inserted through a slot in
the end of the socket and driven into the ground passing through
the slot. Wings are also attached to the socket to prevent rotation
of the socket once inserted in the ground. To remove the socket
from the ground the bar must first be removed before the socket can
be removed. No reference is made as to how to remove the socket
from the ground.
[0004] Ground anchors also exist which can be inserted into the
ground using a rotary motion. These devices, which comprise a shaft
and blades, act as augers and displace the ground around themselves
as they are rotated to generate a hole and thus do not act as a
very stable anchor point.
[0005] There is therefore a need for a ground anchor which can be
driven into the ground without the use of a mallet or the like,
which can be easily removed without the need for the use of
excessive force and which forms a stable anchor point; such a
device is disclosed herein.
SUMMARY OF THE INVENTION
[0006] An anchoring device comprising a shaft, at least part of
whose length comprises a tapered portion, with at least one helical
flange which runs substantially along the length of said tapered
section and an engagement means to allow the device to engage with
a lever wherein in use rotation of the lever about the axis of the
shaft results in rotation of the device such that the tapered
portion and the helical flange co-operate to drive the device into
the ground.
[0007] The co-operation of the tapered portion and the helical
flange is such that the device is actually driven into the ground
i.e. is self tapping. The device is driven into the ground by a
pulling action generated by the helical flange(s) acting against
the ground surrounding the flange(s). It is believed that other
anchoring devices, which use a rotational means to drive the anchor
in to the ground, actually use an auger type action i.e. they
displace the ground around themselves as they are rotated. The
invention disclosed herein merely compresses the ground surrounding
the device to generate a space appropriately sized for the device.
Thus the device disclosed herein can be simply withdrawn from the
ground by rotation of a lever in the appropriate direction when
engaged with the device. The fact that the ground surrounding the
device has not been displaced thus results in a more efficient
removal of the device from the ground and additionally forms a more
stable anchor in use.
[0008] Optionally the tapered section occupies a majority of the
length of the shaft. The provision of a large tapered section in
this way assists the insertion of the shaft into the ground as the
passageway generated by the insertion of the shaft is gradually
increased in size.
[0009] Optionally the diameter of the helical flange is uniform
along the majority of the length of the tapered portion of the
shaft. It has been found that this arrangement results in a ground
anchor which drives into the ground rather than acting as an auger
which displaces the ground around itself.
[0010] Preferably a plate is positioned perpendicular to the length
of the shaft at or adjacent the end of the device distal from the
said tapered portion. In use, once the length of the shaft has been
screwed into the ground the plate engages with the ground
immediately above the shaft compressing said ground around the
device such that the device is more rigidly fixed in place.
Additionally the plate improves the stability of the device in the
ground by preventing horizontal movement of the device.
[0011] Preferably, the anchoring device further comprises a masonry
bit attached to the end of the shaft adjacent said tapered portion.
The incorporation of a masonry bit in this way enables the device
to be used in stony ground without the risk of damage to the end of
the shaft entering the ground, which might otherwise be caused by
this end striking stones and other such obstructions.
[0012] Preferably the shaft further comprises a second tapered
section proximal to the end of the shaft distal to the tapered
portion wherein the cross-section of the shaft increases in a
direction away from the first tapered portion of the shaft. The
incorporation of this second tapered section improves the stability
of the device once inserted in the ground by further reducing
horizontal movement of the device. The incorporation of the second
tapered portion of the device is believed to be very important to
the effective functioning of the device. It is believed that the
second tapered portion compresses the ground surrounding the second
tapered portion in an outwards direction (away from the central
axis of the device) as the device enters the ground in use.
[0013] Preferably the shaft of the device is hollow and further
comprises a threaded section in the hollow. In this way a variety
of attachment means may be connected to the device and interchanged
as required i.e. hooks, cleats and eyelets. The hollow centre of
the device provides additional benefits when the device is
manufactured from plastics material i.e. the hollow centre of the
device increases the rate of cooling of the plastics material after
the initial formation of the device such that deformation of the
device during the cooling process does not occur.
[0014] Preferably small protrusions are present on the first
tapered portion of the shaft. The inclusion of small protrusions on
the shaft breaks up the ground surrounding the shaft. This reduces
the friction between the shaft and the ground such that the force
required to drive the device into the ground is reduced.
[0015] More preferably the protrusions are pyramidal in shape.
Protrusions of this shape have been found to be particularly
effective at reducing the force required to drive the device into
the ground.
[0016] Preferably the device is colour coded. Colour coding can be
used to indicate different sizes of device and/or to indicate the
thread size of the internal hollow section and/or colour can be
used to indicate the purpose for which the device is intended to be
used e.g. for use in particularly stony ground or soft ground, or
to indicate that the device is intended to be used in combination
with other similar devices e.g. to fix a plate to the ground such
that a vertical pole such as a signpost can be attached.
[0017] Preferably the device incorporates drainage holes to prevent
the retention of water in the hollow shaft and/or in the engagement
means of the device. The incorporation of such drainage holes
prevents the retention of water by the device which might otherwise
act as pools which insects such as mosquitoes could utilise for the
purpose of reproduction.
[0018] Included within the scope of the invention is a ground
anchor substantially as described herein with reference to and as
illustrated by any appropriate combination of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The invention will be described by reference to the
accompanying drawings in which:
[0020] FIG. 1 is a schematic side view of a ground anchor according
to the present invention.
[0021] FIG. 2 is a schematic perspective end view showing an
engagement means according to the present invention.
[0022] FIG. 3 is a schematic perspective view of a ground anchor
according to the present invention with a fluted shaft and a single
helical flange; and
[0023] FIG. 4 is a schematic side view of a ground anchor with a
fluted shaft and a single helical flange.
[0024] FIG. 5 is a schematic side view of a preferred embodiment of
a ground anchor according to the present invention incorporating a
single helical flange and a hexagonal shaped engagement means.
[0025] FIG. 6 is a schematic perspective view of a preferred
embodiment of a ground anchor according to the present invention
incorporating a single helical flange and a hexagonal shaped
engagement means.
[0026] FIG. 7 is a schematic perspective view of a preferred
embodiment of a ground anchor according to the present invention
incorporating a single helical flange and a hexagonal shaped
engagement means.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] Wherever possible the same numbers have been used to
indicate the same feature on different embodiments of the invention
described herein. Reference is initially made to FIG. 1 of the
drawings which shows a schematic side view of a ground anchor
according to the present invention as generally indicated by 10.
The ground anchor comprises a shaft generally indicated by 11,
which has a first tapered portion 12, an untapered portion 13 and a
second tapered portion 14. The anchor further comprises a plate 15
and an engagement means 16.
[0028] The cross-section of the second tapered portion of the shaft
14 increases in diameter in a direction away from the central
longitudinal axis of the shaft 11.
[0029] Two helical flanges 17 are present along the first tapered
portion 12. It will be noted that the first tapered portion 12 and
associated helical flange 17 comprise over half, a major part, of
the total length of the shaft 11. A masonry bit 18 is attached to
the free end of the first tapered portion 12.
[0030] The plate 15 is of a wider cross-section, relative to the
axis of the shaft than the widest part of the second tapered
portion 14. The thickness of the plate 15 is sufficient that it can
withstand pressure exerted on it, via the ground, when a rotational
force about the axis of the shaft is applied to a lever engaged
with the engagement means 16.
[0031] The diameter of the helical flanges 17 is uniform along the
majority of the length of the first tapered portion 12.
[0032] Small protrusions 19 are present on the first tapered
portion of the shaft, these may be rounded as shown on FIG. 1 but
they are preferentially pyramidal 19a in shape as shown on FIG. 4,
FIG. 5 and FIG. 6.
[0033] Reference is now made to FIG. 2 of the drawings wherein a
schematic perspective end view is provided of the ground anchor
shown in FIG. 1.
[0034] The engagement means 16a and 16b shown comprises a triple
surface engagement means but any suitable engagement means as would
be known to a person skilled in the art may be used, e.g. hexagonal
nut, star shaped sockets, slots, Philips head etc.
[0035] A first set of drainage holes 21 is incorporated into the
plate 15 at equal circumferential spacings and a second set of
similarly equally circumferentially spaced drainage holes 22 are
incorporated between the two parts 16a and 16b of the engagement
means. The lower portions of the drainage holes 22 pass through the
second tapered portion 14 of the ground anchor, as can be seen on
FIG. 1.
[0036] The centre of the shaft is hollow, as generally indicated by
23. The hollow section 23 runs down the shaft 11 to the point where
the tapered portion 12 begins.
[0037] A threaded section 24 is incorporated into the hollow of the
shaft 23. A drainage hole 31, as shown on FIG. 3, FIG. 4 and FIG.
5, may be incorporated into the bottom of the hollow shaft 23 or
alternatively a plug, not shown, may be provided to block off the
hollow shaft when appropriate.
[0038] The device (ground anchor) 10 of the present invention may
be made from steel, plastics material, aluminium or any other
material suitable for the purpose to which the device is to be
used. The preferred plastics material used is polypropylene and an
especially preferred material used is short glass fibre reinforced
polypropylene. The use of short glass fibre reinforced
polypropylene gives a ground anchor which is considerably stronger
and more hard wearing than devices formed from polypropylene
alone.
[0039] The use of short glass fibre reinforced polypropylene has
the additional benefit that the ground anchor has considerably
increased tensile strength at lower temperature i.e. down to, and
below 0.degree. C.
[0040] A ground anchor formed from short glass fibre reinforced
polypropylene which incorporates a masonry bit 18 is capable of
being used in much harder material than would otherwise be
possible. Such a ground anchor may even be used in concrete
provided a bore hole, corresponding to the length of the anchor to
be used, is initially drilled in the concrete.
[0041] The masonry bit 18 is preferably incorporated into the
ground anchor during the moulding process in order to provide
maximum strength to the device thus formed.
[0042] The embodiments shown in FIG. 3, FIG. 4, FIG. 5, FIG. 6 and
FIG. 7 utilise a single helical flange 17a which has been found, in
use, to be considerably more effective than a device incorporating
a double helical flange. The use of a device utilising a double
helical flange, as shown in FIG. 1 and FIG. 2, was found to act as
an auger displacing the ground around the device in use,
particularly when the device was used in soft ground.
[0043] The embodiment of the ground anchor shown in FIG. 5, FIG. 6
and FIG. 7 utilises a hexagonal shaped engagement means 16a. A
first set of drainage holes 21 is incorporated into the plate 15 at
equal circumferential spacings and a second set of similarly
equally circumferentially spaced drainage holes 22a are
incorporated into the hexagonal shaped engagement means 16a. The
lower portion of the drainage holes 22a passing through the second
tapered portion 14 of the ground anchor, as can be seen on FIG. 5
and FIG. 6. The incorporation of the first and second set of
drainage holes assists in decreasing the weight of the ground
anchor disclosed.
[0044] In use, the anchoring device is driven into the ground by
use of a suitable lever, as would be known to the skilled
addressee, which incorporates suitable engagement means to engage
with the engagement means 16/16a of the device.
[0045] Rotation of the lever, when engaged with the ground anchor,
about the axis of the shaft in the appropriate direction causes the
tapered portion 12 (of a device incorporating a single helical
flange 17a) to co-operate with the helical flange 17a such that the
device is driven (i.e. pulled) into the ground by the helical
flange 17a. Additionally as the helical flange 17a enters the
ground, the ground (when it is a soft material such as soil)
surrounding the flange 17a is compressed by the flange 17a as a
result of pressure exerted by rotation of the lever.
[0046] It is believed as the second tapered portion 14 enters the
ground it compresses the surrounding area, in the ground, in an
outwards direction (away from the central axis of the ground
anchor) as it is pulled into the ground by the helical flange
17a.
[0047] The ground anchor is rotated via the lever (and so driven
into the ground) until the plate 15 engages with the ground, the
force subsequently exerted, results in the plate 15 pressing
against the ground such that the ground surrounding the shaft 11 is
compacted.
[0048] The second tapered portion 14 and the plate 15 thus
co-operate to produce a compressed section of ground which
surrounds the upper section of the ground anchor ensuring that the
anchor (device) 10 is securely fixed in the ground, thus reducing
horizontal and vertical movement of the device in use.
[0049] The use of a long tapered portion, relative to the overall
length of the shaft 11, gives a smooth entry of the device into the
ground such that the device is driven (pulled) into the ground (by
the helical flange) rather than acting as an auger which displaces
the ground around itself This action is further assisted by the use
of a helical flange 17/17a wherein the flange is a uniform diameter
along the majority of its length and only narrows at either end.
The uniform diameter of the helical flange 17/17a results in the
force that drives the anchor into the ground acting over a much
larger area than would be the case with a flange which only
gradually broadens and then gradually narrows along its length. The
anchoring device 10 can be removed by the use of a suitable lever
incorporating appropriate engagement means to engage with the
engagement means 16/16a of the ground anchor.
[0050] The incorporation of a masonry bit 18 allows the device 10
to be used in particularly stony ground without the risk of
damaging the tip/end of the device should it strike a stone.
[0051] Once driven into the ground, the hollow shaft 24, in
combination with the threaded section, provides a means for the
attachment of cleats, hooks, eyelets etc., which have complementary
threaded sections. Other items such as guide ropes can subsequently
be attached to the cleats, hooks, eyelets etc.
[0052] It will be appreciated that ground anchors of the type
disclosed herein may be used to affix other items to the ground,
provided suitable holes are incorporated into the items, or
suitable attachment means are used as would be known to the skilled
addressee, e.g. to affix the legs of benches to the ground.
[0053] The device may further comprise a second helical (fluted)
portion 20 formed as a recess in the untapered portion 13, as shown
on FIG. 4. Such a recessed helical portion assists the entry of the
device (ground anchor) into the ground.
* * * * *