Patent Application
20090025332
1. Field of the Invention
This invention relates to a re-usable support structure for a pole, post, mast or other elongate member; the basis of which is a reversibly lockable ground anchor to be inserted in the ground or other substrate.
2. Description of the Related Art
A wide variety of activities depend on the temporary placement of poles in the ground or in a flat floor, road or other substrate, to serve a purpose for a defined period and then to be removed until needed again. Applications include road signs and traffic control measures, advertising or information signs, fences for animal control or crowd control, posts for use when playing sports, tent poles, Christmas tree supports, poles/posts for carrying utility wires, and the like. The invention is more particularly applicable to those activities that require repeated placement, removal, and replacement of poles in or near the same place and where in the absence of the pole the area should be free of obstruction.
Past solutions to this need include: providing posts with heavy laterally spread-out bases that sit upon the ground, forcing posts into the ground so that they are held by friction against the ground around the lowest part of the post, embedding posts into concrete, ice, or some other material which can set around the base of the post, and/or making use of mechanical gripping devices such as keys, wedges, or collets.
Despite the existence of prior art using collet/wedge devices for magnifying a gripping action, there are disadvantages such as the use of a separate tightening collar to be placed around the pole, and operating along a helical screw thread (Partee) and the need in many cases for a part of the anchoring system which remains projecting from the ground even when the pole is not installed.
The inventors were surprised to learn that some expensive, stainless-steel pole assemblies such as flagpoles are sold yet no corresponding system for repeated removal and replacement is offered, apart from sawing off that part of the pole extending from the ground and leaving the remainder embedded in the concrete base.
The problem to be solved could be summarized as being to devise a simple but effective pole-retaining apparatus capable of allowing the pole to be removed and replaced from time to time, and in addition, having minimal impact on an area when the pole is not in place.
A survey of prior art reveals that many sockets to hold poles, such as basketball goal support poles or sign holders, have been described, and many of those include some form of taper lock or collet.
Few if any provide a sound support and/or teach particular insertion or removal tools so that removal is (a) limited to those authorized to do so, and (b) can be carried out reliably and without damage when required. U.S. Pat. No. 5,571,229 to Fitzsimmons et al (dated 1996), (also U.S. Pat. No. 5,752,349) teach an embedded shell, a collet, and use of tapers. In this case, the shell around which the concrete or earth is to be molded is supplied in two halves which are locked together before insertion under the ground surface. The resulting shell plus cap has a rectangular profile in vertical section, except for an inwardly tapered lower end and an inwardly tapered upper opening, comprising a nylon, internally threaded cap that closes down over a series of short tabs, forcing them into the post just below where it emerges from the cap. This is in marked contrast to the single-piece shell with apposed full-length collets and locking means of the present invention, as described below. The post must have a round cross-section. If the post moves upward, perhaps because of vibrations inducted by vigorous play or by wind) after being locked in place, the lower restricted area that makes contact between the post and the shell soon comes out of contact. The only tool used to clamp or release the post is hammer and wedge means to tighten or loosen the nylon cap so that it screws up or down.
Riker (U.S. Pat. No. 7,003,919) teaches a straight-pipe shell to go in the ground, usually into concrete, and a tapered collet surrounding a short portion of the post within the upper end of the shell. Again, there is only a short length of the tapered outer surface of the collet in contact with an adjacent straight cylindrical section, even though the resilience of the preferred plastics will encourage a little deformation.
Sofy (U.S. Pat. No. 5,497,972) teaches a support for a Christmas tree in which a one-piece molded skirt with tapered petals serves as a surround of collets to hold a pole within a base. The skirt co-operates with, when inserted within, a uniformly tapered hole presented to an upper aspect of a base to provide a tapered clamping surround to a cylindrical pole. Screws hold the skirt onto the base and when undone, allow the pole to be removed.
In a first broad aspect this invention provides anchoring means for fastening an elongate member into a substrate, said elongate member having a foot of substantially constant cross-section, said anchoring means including:
at least one elongate collet having an inward face shaped to fit along and around a section of said foot;
and an elongate housing having an internal cavity shaped and dimensioned to house said at least one collet and said foot in combination;
wherein said at least one collet each has a top end and a bottom end, and an outward face which tapers inwardly from said top towards said bottom in a first portion near said top end and in a second portion near said bottom end, and wherein said internal cavity of the housing tapers inwardly in a corresponding first and second portion;
whereby in use downward pressure on a said collet can create wedging contact between said outward face and said housing near said top end and near said bottom end.
Preferably said outward face of each said collet is untapered between said first tapered portion and said second tapered portion, whereby in use substantially no wedging contact occurs between it and the housing between said first and second tapered portions.
Preferably said at least one collet and said housing are formed from a resilient plastics material.
Preferably the anchoring means includes two said collets forming substantially complementary parts of a sleeve shaped and arranged to surround said foot in use.
Preferably said at least one collet includes an outwardly projecting flange at said top end.
Preferably said housing includes a collar shaped and arranged to house said flange.
Preferably said collect includes a longitudinal slot extending downwardly from said top end;
the anchoring means further including a key shaped and dimensioned to fit into said slot, to engage between said foot and said housing through said collet in use.
Preferably said housing further includes a recess and a metal backing plate arranged to be engaged by said key in use.
Preferably said key comprises a flat blade having an edge arranged to engage with said foot in use, said edge being concave in cross-section so as to provide paired parallel sharp edges.
Preferably said key includes a flange at a top end thereof, substantially corresponding in size and shape with a section of said slotted collet, so as to sit flush with the top end of said collet in use.
Preferably said inward face of each said collet includes a plurality of transverse ribs near said top end and near said bottom end, to engage with said foot in use.
Preferably said housing includes at least one aperture at or near said bottom end, dimensioned and arranged to admit electrical wiring.
Preferably said housing includes at least one frangible membrane, dimensioned and arranged to admit electrical wiring when punctured in use.
Preferably said housing includes at least one longitudinal rib on a wall of said internal cavity, adapted and arranged to key with said at least one collet, to prevent rotational movement of said one or more collets around said housing in use.
Preferably one of said foot and said housing includes a transversely projecting pin, and the other includes a transversely extending aperture therein shaped and arranged to engage on said pin, whereby in use downward pressure on a said collet can press said pin into engagement with said aperture, such that longitudinal movement of said foot relative to said housing is prevented by said pin.
Preferably said housing includes one or more projections on an external surface thereof, to engage with said substrate in use.
Preferably the anchoring means includes a collet-removing tool comprised of a handle, a fulcrum, and a crescent-shaped head extending transversely relative to said handle and offset relative to said fulcrum, whereby the tips of said crescent-shaped head can be engaged under said projecting flange at the top end of a said collet, and used to lift said collet with leverage against said fulcrum applied with said handle in use.
Preferably said tool further includes a bearing block adapted and arranged to fit under said fulcrum.
Preferably said head is pivotally mounted with respect to said handle and said fulcrum.
Preferably the anchoring means includes a cap, dimensioned and adapted to engage into said collar.
Preferably said cap is annular, and is dimensioned and arranged to fit around said elongate member.
In another broad aspect the invention provides a method for fastening an elongate member in a substrate using the anchoring means described above, comprising the steps of:
setting a said housing into a hole in said substrate, using a settable fluid construction material such as concrete;
inserting a foot of said elongate member into the internal cavity of said housing;
inserting at least one said collet alongside said foot into the internal cavity of said housing;
applying downward pressure on said at least one collet to create wedging contact between said collet and said housing near the top end and near the bottom end.
Preferably a said collet includes a longitudinal slot extending downwardly from said top end, and said anchoring means further includes a key shaped and dimensioned to fit into said slot;
further including the step of fitting said key into said longitudinal slot to engage between said foot and said housing through said collet.
Preferably the method further includes the step of applying an annular cover over said housing around said elongate member, and engaging said cover in a collar on said housing.
In a further broad aspect the invention provides a method for removing an elongate member fastened in a substrate using the anchoring means described above, comprising the steps of:
engaging the tips of said crescent-shaped head of the tool under a projecting flange of a collet; applying pressure to said handle of the tool, to lift said collet with leverage against said fulcrum; removing said collet;
and removing said elongate member without damage to the components of the anchoring system.
In a further broad aspect the invention provides apparatus and a method for mounting a post for a fence, wherein the post of the fence has a rectangular cross-section and the collets and housing are shaped accordingly.
The description of the invention to be provided herein is given purely by way of example and is not to be taken in any way as limiting the scope or extent of the invention.
Throughout this specification, unless the text requires otherwise, the word “comprise” and variations such as “comprising” or “comprises” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.
The orientation terms top or bottom or other references to a vertical or horizontal orientation are used for clarity of explanation, but it will be appreciated that the invented apparatus may be oriented in any direction and in such a case these terms must be translated accordingly.
In summary this specification describes a quick release locking system for ground fixtures particularly a post A having a constant cross-section, and provides a ground-embedded housing B, a pair of free-standing locking members (collets or wedges) C, and a key D. Tools for inserting, locking and later removing the locking member are described. In use, the post A is placed loosely in the internal cavity of the embedded housing B then one locking member C is driven down on each side of the post. It may be that only one locking member C is hammered into place.
The preferred locking members (called collets or wedges) C are shaped (preferably by injection molding or equivalent procedure) to fit closely against the post cross-section on an inward face, and to fit closely inside the housing on an outward face, and are preferably made of a plastics material in order to provide a little resilience that increases contact area; and to provide resistance against corrosion.
This invention relates to a system for reversibly anchoring a post (or pole, pipe, shaft, beam, mast, etc) in a substrate (2) such as the ground or a wall. The illustrations and the key to the part identification includes many details. In principle the invention employs two main components—the housing, permanently buried at a designated spot, and one, two, or more wedges of a type known as collets because they are shaped to wrap around a shaft together with anti-rotation means, locking means, and removal means.
Post A: may be a hollow conduit or pipe carrying fluids or protecting conductors such as copper wiring or fiber optic materials. Preferably the post A is made of a slightly deformable material—as per
Housing B: This is a shell (hatched thick line B in the elevation section of
Collet C: is a shaped wedge not unlike collets used in engineering to hold tools with a locking process effected by forcing the tapered collet into a tapered hole. The basic collet comprises perhaps a third or a half-circle around the post A, as seen in plan view, shaped so that the inward surface J generally conforms to the exterior of the post A, preferably with horizontal ribs G at upper and lower parts of the inward surface J, to resiliently deform against and/or press into the post A to grip it securely at an upper and a lower part of the collet. The outward surface H conforms to inner wall of the housing B, with attention given to the angles of the upper and lower tapered areas T1 and T2. Specific collets may be provided for different sizes and shapes of post and for a lesser variety of housings. A square peg can be fitted into a round hole with this system using appropriately shaped collets, as shown in
The apposable tapered zones (T1 and T2) on the housing B and the collet C serve to wedge the pole and the collet into place when downward pressure is applied to the collet. Use of an upper and a lower taper both having a significant tapered area tends to make a more stable mount since the item held cannot rock to and fro against any high point or obstruction in the mid-height part of the anchor. Of course the inter-taper length has to be well controlled so that both tapers co-operate to hold the pole in place. With a continuous taper a similar pressure would be applied right through the supported area, making the locking system of the invention susceptible to vibration and flexing by rocking about the middle.
Suitable materials for collets include metal which may be cast or milled, but more preferably are a tough plastics material, including for example polypropylene and high-density polyethylene, which may be made by injection molding. The slight flexibility of this material provides an advantage in combination with the use of two tapered zones as described above. When removing the collet, the top tapered zone T1 can be pulled free with leverage applied to the top of the collet, while the other zone T2 remains wedged. The intermediate area is stretched out. The pulling force then transfers to the second zone T2, to release it also. If the collet were formed from an inflexible material, or if the taper extended continuously along the entire length of the collet, a much greater pulling force would be required to free the whole wedged section of the collet at once.
Each plastic material has its own shrinkage characteristics. Preferably collets are made in a single molding operation but the known effects of plastics-dependent shrinkage such that which occurs after release from the die may necessitate subsequent finishing operations—although the cost of those is mitigated by the use of cheaper plastics. Cutting, grinding with NC machines and brief searing contact with very hot shapes are possible techniques for post-finishing. Preferably all parts of the finished item are made at the same thickness, to help in the cooling characteristics, as is known in the relevant arts.
The collet C may be modified to accommodate locking devices, as described below, with slots W or R as shown in
Key D: As shown particularly in
The post should be prevented from rotating or from being rocked from side to side and then working its way out of the mount.
A further type of key is designed to prevent the housing from spinning around inside the ground material, typically cast concrete.
Lock Pin P: A further means may be provided for preventing rotation and/or withdrawal of the post A from the anchoring means, as shown in
Collet removal: Two configurations of lever for use in collet removal are shown in
Preferably, the tool V is formed and arranged so that the fulcrum X will bear against the substrate 2 in which the housing B is mounted, rather than the housing B itself. Often an air gap may be caught above the poured concrete and under the collar L of the housing B, and without the support of the substrate material the collar L may be too weak to bear the pressure of the fulcrum X. Accordingly a separate bearing plate Y may be provided, to lie between the fulcrum X and the collar L, and/or the head U may be pivotally mounted (U2 in
It will be appreciated that the shape of the tool will be modified to suit the dimensions and shape of the collets C used in a particular application N for example, if the system is applied in a square form for mounting square-section posts (as described below) then the collet removing tool V will have a straight or V-shaped head U, rather than the crescent-shaped head U described above.
Other removal procedures: It will be appreciated that the same or a similar tool V2 may be used to extract the key D. It will also be appreciated that other means may be used to extract the collets from the housing, such as for example a screw passing vertically down through a threaded aperture in the head K of the collet, and bearing against a plate on the collar L, which can raise the collet when turned, as shown in
Caps and covers: An injection molded cap (172 in
Differing sectional profiles:
b also shows how a hexagonal section pole can be accommodated. 1300 is the wall of the shell placed against soil or concrete or the like. 1301 is the outline of a hexagonal pole; commonly supplied in rolled sheet metal or the like with an overall taper for street lighting applications, for example. The hatched outline 1304 is an example of one 120 degree collet and the hatched outlines 1304b1 and 1304b2 are examples of yet another, 60 degree collet outline. These two types could be used at the same time, or used only as one (either) type at a time.
There are some applications such as crowd control, where posts may be erected but if pressure becomes too great (such as during emergency emptying of a stadium) it is desirable that the posts give way in a safe manner. Posts can be provided for use with the above anchoring system that snap cleanly at ground level when over-stressed so that (for example) if a crowd in panic has trampled down the posts, individuals are not injured on protruding stumps thereafter. Later, the broken-off base can be extracted and the entire post can be replaced cheaply without having to pour new concrete, for example. Roadside signs should also break into a safe configuration if hit by a vehicle.
It will be appreciated that this invention provides apparatus and a method for removably fixing in place a pipe or other elongate member passing through or into a wall using anchoring means as described above, applied horizontally instead of vertically.
Anchors for Hand Rails into Walls
A process as above can be used to anchor an end of a hand rail into a wall made of such as brick or concrete.
Concrete floors and galvanized iron pipework serving as fencing, bails, and races is widely used in New Zealand at least for the construction of animal yards, cowsheds, and in other countries for barns to house animals. When the pipes are directly set into the concrete, corrosion in electrolytic cells may be set up for wet concrete is a reasonably good conductor, and the pipes cannot be moved around. One application of the present invention is to provide non-conducting sockets for pipes which minimize corrosion, even if some pipes are of stainless steel and others are of galvanized iron,
Considering the invention as means to provide reversible, secure anchoring of a post in the ground, applications include:
temporary reading and advertising signs,
temporary, easily restored removable guard-rails, fencing, traffic or crowd control posts or supports,
sports or playground fixtures such as for goal posts at specific places when a given sports code is “in season” and replacement by a cover otherwise,
playground fixtures such as of the type based on vertical pipes rising out of the ground—allowing reconfiguration from time to time,
preventing vehicle access to a space by all but approved vehicles,
providing temporary watering stations such as in an orchard during a frosty season,
providing removable stock yards for a farm—particularly for the more boisterous animals such as cattle and deer which are likely to “supersede” temporary yards not dug into the ground.
Finally, it will be understood that the scope of this invention as described and/or illustrated herein is not limited to the specified embodiments. Those of skill will appreciate that various modifications, additions, known equivalents, and substitutions are possible without departing from the scope and spirit of the invention as set forth.
| Number | Date | Country | Kind |
|---|---|---|---|
| 543906 | Dec 2005 | NZ | national |
This application is a continuation of International Application PCT/NZ2006/000314, filed on Dec. 1, 2006.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/NZ2006/000314 | Dec 2006 | US |
| Child | 12129620 | US |
