Stake for anchoring in the ground

Abstract

The invention relates to an anchoring stake intended to be sunk into loose or sandy ground (10), comprising: - a longitudinal and rectilinear body (2), the distal end (3) of which is in the form of a point (3), said body being made of a semi-rigid material, - rectilinear side arms (4a, 4b, 4c, 4d) secured to the body (2) by their end (40a, 40b, 40c, 40d) that is closest to the point (3), and the other ends (41 a, 41 b, 41 c, 41 d) of which are free, said arms being arranged along said body and being distributed over the periphery thereof, - the side arms (4a, 4b, 4c, 4d) number at least four, - the body (2) and the side arms (4a, 4b, 4c, 4d) are made from a biodegradable plastic, - the ratio between the initial length of the side arms (4a, 4b, 4c, 4d) and their initial width is between 15 and 20, - and the ratio between the initial length of the side arms (4a, 4b, 4c, 4d) and their initial thickness is between 15 and 20.

Description

Description Title: Ground anchor stake. [Technical field. [1] The invention relates to an anchoring stake in the ground. [2] The invention relates to anchoring stakes used in particular for the installation and fixing of objects such as textile tarpaulins, turf, canvas, geotextile or other soft, flexible and thin material. State of the art. [3] We know of stakes complex enough to allow, regardless of soil consistency, satisfactory anchoring, as described in patent application FR2945554. But such piles are relatively complex to manufacture and implement and are therefore too expensive for a use which is nevertheless very simple and which is sometimes only temporary. [4] Patent document FR2979926 describes an anchoring stake designed to be driven into soft soil, comprising a cylindrical body with axis XX', the distal end of which is pointed. This stake includes at least two lateral arms attached to the cylindrical body at their ends closest to the point, with the other ends free. The arms are arranged along the body and evenly distributed around its periphery. One observed drawback is that, in practice, these stakes are not very stable when installed in soft or sandy soils. Furthermore, this type of fixing is not necessarily intended to last for several decades, so these stakes remain buried in the ground and become a source of pollution once the object to be fixed is removed and / or replaced. [5] The invention aims to remedy this situation. In particular, one objective of the invention is to provide an anchoring stake whose design ensures improved stabilization in loose or sandy soils. Another objective of the invention is to provide an environmentally friendly and durable anchoring stake that has a limited impact on soil pollution. Presentation of the invention. [6] After multiple trials and attempts, the applicant developed an anchor stake that enabled him to achieve the aforementioned objectives. [7] The anchor stake according to the invention is intended to be driven into soft or sandy soil. It comprises a longitudinal body with a pointed distal end and a flat, disc-shaped proximal end, the body being made of a semi-rigid material. Straight lateral arms are attached to the body at their ends closest to the pointed end, the other ends of which are free. These arms are arranged along the body and distributed around its periphery. [8] This anchor stake is remarkable in that it has at least four lateral arms and that the body and lateral arms are made of biodegradable plastic. Furthermore, the ratio of the arms' length to their width is between 15 and 20, and the ratio of the arms' length to their thickness is also between 15 and 20. [9] Such an anchoring stake is much more stable in loose or sandy soils than the stakes described in the aforementioned patent document FR2979926. Furthermore, this stake has no impact on the environment.

[0010] Other advantageous features of the invention are listed below. Each of these features may be considered alone or in combination with the notable features defined above. Each of these features contributes, where applicable, to the resolution of specific technical problems defined further in the description and in which the notable features defined above do not necessarily participate. The latter may, where applicable, be the subject of one or more divisional patent applications. - According to one embodiment, in the resting position, the arms move away from the body from their end attached to it towards the free end at an angle of no more than 5°. - According to one embodiment, the point has a bevel, which bevel defines an inclined face with a slope which is between 30° and 45°. - According to one embodiment, the free ends of the lateral arms each have a bevel, which bevel defines an inclined face with a slope which is between 5° and 20°. - According to one embodiment, the body has a hook-shaped proximal end. - According to one embodiment, the biodegradable plastic used has a flexural modulus greater than 0.7 GPa at 20°C and 50% relative humidity and more preferably between 1.5 GPa and 2.5 GPa at 20°C and 50% relative humidity. - According to one embodiment, the lateral arms are arranged in pairs, each pair being located at the same level on the body. - According to another embodiment, the lateral arms are arranged in pairs, each pair being located at different levels on the body. - According to one embodiment, the lateral arms of one pair have the same length and / or the same shape as the arms of another pair. - According to another embodiment, the lateral arms of one pair have a length and / or shape distinct from the arms of another pair. Brief description of the figures.

[0011] Other advantages and features of the invention will become clearer upon reading the description of a preferred embodiment which follows, with reference to the attached drawings, which are provided as illustrative and non-limiting examples and on which: [Fig. 1] is a schematic top view of an anchor stake according to the invention. [Fig. 2A] is a front view of an anchor stake according to an embodiment of the invention. [Fig. 2B] is a side view of the spike in figure 2A. [Fig. 3A] is a front view of an anchor stake according to another embodiment of the invention. [Fig. 3B] is a side view of the spike in figure 3A. [Fig. 4] is a front view of an anchor stake according to yet another embodiment of the invention. Description of the implementation methods.

[0012] The anchoring stake according to the invention is particularly intended for installation in loose or sandy soil. The stake installation method is similar to that described in the aforementioned patent document FR2979926, to which those skilled in the art may refer.

[0013] In the context of the present invention, a soil is described as "loose or sandy", such that when such a stake 1 is pressed down with its lateral arms (using a hammer, bare hand or foot) with a force of up to about 35 kg, it sinks into the soil 10. The stake with its lateral arms can however be used for soil requiring a bearing force exceeding 35 kg.

[0014] The stake 1 has a longitudinal and straight body 2 whose cross-section can be cylindrical, square, oblong, grooved, etc. The length of the body 2 is between 10 cm and 30 cm and its diameter (or thickness) is between 5 mm and 20 mm.

[0015] The body 2 has a distal end 3 in the form of a point. In one embodiment, this point 3 has a bevel 30. The bevel 30 defines an inclined face with a slope advantageously between 30° and 45°. Such a beveled point allows for better penetration into the object O and / or into the soil 10. The applicant has further observed that this bevel 30 improves the straightness of the driving trajectory of the stake 1 into the soil 10, by limiting lateral deviations.

[0016] The body 2 also has a proximal end 6 opposite the distal end 3. In figures 2A, 2B, 3A and 3B, the proximal end 6 is in the form of a flat head perpendicular to the longitudinal axis of the body 2. The diameter of the head 6 can, for example, be between 2 cm and 6 cm, and its thickness, for example, between 2 mm and 10 mm.

[0017] The stake 1 may also include a washer 7, which can be made of the same material as the body 2. This washer 7 slides along the body 2, resting under the head 6 to sandwich the object O with the ground 10. The washer 7 is not essential, but improves the support and stability of the object O against the ground, preventing the head from penetrating or being driven into the object O and / or damaging it. The washer 7 advantageously has notches for the passage of the arms 4. The diameter of the washer 7 can, for example, be between 5 cm and 10 cm, and its thickness, for example, between 1 mm and 5 mm.

[0018] In the embodiment shown in Figure 4, the proximal end 6 is hook-shaped with a diameter ranging from 10 mm to 20 mm. This hook 6 is configured to hold a pipe 60, such as a garden hose or drip irrigation system. In this application, the stake 1 may not be used for securing another object, particularly the aforementioned object O.

[0019] According to one feature of the invention, the stake 1 (i.e., the body 2, the arm 4, the head 6, and the washer 7, if applicable) is made of biodegradable plastic. The advantage of using biodegradable plastic is that, over time, the stake 1 will degrade in the soil environment into non-toxic components, so that it is not necessary to remove it from the soil when the object O to be fixed is disassembled and / or replaced.

[0020] According to a preferred embodiment, the biodegradable plastic meets the ASTM D6400 biodegradation standards. The biodegradable plastic is also advantageously hydrophobic.

[0021] The rigidity of the plastic composition is important in the ability to drive the stake 1 into the ground 10 without deformation. Preferably, the biodegradable plastic used has a flexural modulus greater than 0.7 GPa at 20°C and 50% relative humidity, and more preferably between 1.5 GPa and 2.5 GPa at 20°C and 50% relative humidity.

[0022] The biodegradable plastic used is advantageously chosen from the following family: cellulose acetate butyrate; proportionate cellulose acetate; thermoplastic starch; chemically modified starch such as starch acetate or starch maleate; polylactic acid; polyhydroxyalkanoate; biodegradable synthetic polyester; polyurethane based on bio-sourced polyols derived from soy polyols, castor oil polyols, or a mixture thereof; 100% natural materials, for example corn or sugar cane, which material is mixed with a plasticizer.

[0023] During the biodegradation process, the physical properties of the plastic tend to deteriorate, reducing the ground anchorage of the stake 1. To remedy this, and according to a feature of the invention, the stake 1 comprises at least four straight lateral arms 4a, 4b, 4c, 4d, attached to the body 2 by their ends 40a, 40b, 40c, 40d closest to the tip 3. Their other ends 41a, 41b, 41c, 41d are free. The arms 4a, 4b, 4c, 4d are arranged along the body 2 and distributed around its periphery. In the accompanying figures, and as shown in particular in Figure 1, the arms 4a, 4b, 4c, 4d are arranged at a TT / 2 ratio. More generally, if stake 1 includes a number N of arms (such as N>4), then said arms are arranged at 2TT / N.

[0024] The arms 4a, 4b, 4c, 4d move away from the body 2 in the rest position, that is, when the stake 1 is stored without any external constraint. The arms 4a, 4b, 4c, 4d move away in the ground 10, like the ribs of an umbrella, when an attempt is made to remove the stake 1.

[0025] According to a preferred embodiment, the arms 4a, 4b, 4c, 4d spread apart by a maximum of 5° in the rest position. The applicant has observed that in practice, beyond 5°, the arms 4a, 4b, 4c, 4d exhibit a structural weakness at their ends 40a, 40b, 40c, 40d, weakening said arms and reducing their anchoring effect in the ground during a pull-out force on the stake 1 (when it is planted in the ground and pulled to remove it).

[0026] To allow the arms 4a, 4b, 4c, 4d to move further away from the body 2 during a pull-out force on the stake 1 and thus increase the anchoring effect in the ground 10, the free ends 41a, 41b, 41c, 41d are advantageously beveled, with the bevel facing the body. The best results in terms of resistance to pull-out force are obtained when the bevel defines a slope inclined presenting a slope which is between 5° and 20° with respect to the longitudinal axis of the arm.

[0027] Preferably, to obtain sufficient anchoring effect and pull-out resistance during the first five years of the biodegradation process, the ratio between the initial length of the arms 4a, 4b, 4c, 4d and their initial width is between 15 and 20. Similarly, the ratio between the initial length of the arms 4a, 4b, 4c, 4d and their initial thickness is also between 15 and 20. By "initial length", "initial width" and "initial thickness", we mean respectively the length, width and thickness of the arms 4a, 4b, 4c, 4d before the stake 1 is buried in the soil 10, the beveled end of said arms not being taken into account. Beyond five years of burial, the soil 10 is generally harder (less loose) so that it is no longer necessary for the arms 4a, 4b, 4c, 4d to maintain an optimal anchoring effect in said soil.According to a preferred embodiment, the length of arms 4a, 4b, 4c, 4d is between 20 mm and 100 mm. For a length of 20 mm, their width is between 1 mm and 1.3 mm and their thickness is between 1 mm and 1.3 mm. For a length of 100 mm, their width is between 5 mm and 6.7 mm and their thickness is between 5 mm and 6.7 mm.

[0028] According to one embodiment, arms 4a, 4b, 4c, 4d are arranged in pairs. In the attached figures, two pairs of arms are shown, but a greater number can be considered (for example, 3 or 4 pairs).

[0029] Each pair can be located at the same level on the body 2 (Figures 2A and 2B) or at different levels (Figures 3A and 3B). Arms 4a, 4b, 4c, 4d located at the same level are particularly advantageous for ensuring optimal anchoring in very soft soils.

[0030] Arms 4a, 4b, 4c, 4d positioned at different levels are particularly advantageous for ensuring optimal anchorage when the soil has distinct loose layers. For example, a layer of sand at the level of the pair of arms 4a, 4b closest to the tip 3 and a layer of gravel at the level of the other pair of arms 4c, 4d. In Figures 3A and 3B, the pairs are spaced so that the free ends 41a, 41b of the arms 4a, 4d are located at the fixed ends 40c, 40d of the arms 4c, 4d. The fixed ends 40c, 40d may however be located above the free ends 41a, 41b, for example by a distance of between 5 mm and 50 mm.

[0031] According to an embodiment that simplifies the design, the arms 4a, 4b of one pair have the same length and / or the same shape as the arms 4c, 4d of the other pair.

[0032] In another embodiment, the arms 4a, 4b of one pair have a different length and / or shape than the arms 4c, 4d of the other pair, so that each pair of arms adapts to the characteristics of the different loose layers to ensure optimal anchorage. For example, a pair of arms 4a, 4b installed in a layer of sand may be longer than the pair of arms 4c, 4d installed in a layer of gravel. For this other pair of arms 4c, 4d, it is also not necessary for the free ends 41c, 41d to be chamfered if the free ends 41a, 41b are. Or vice versa. This feature relating to a difference in length and / or shape of the arm pairs is also advantageous when said pairs are located at the same level on the body 2, particularly to create differentiated pull-out resistance forces.

[0033] The arrangement of the various elements and / or means and / or steps of the invention, in the embodiments described above, should not be understood as requiring such an arrangement in all implementations. Various variants may be envisaged.

[0034] Furthermore, one or more features and / or steps described only in one embodiment can be generalized to other embodiments. Similarly, one or more features and / or steps described only in one embodiment can be combined with one or more other features and / or steps described only in another embodiment.

[0035] The use of the verb "comporter", "comprendre" or "include" and its conjugated forms does not exclude the presence of other elements or steps than those stated in a claim.

[0036] In claims, any reference sign in parentheses shall not be interpreted as a limitation of the claim.

Claims

Demands

1. (Anchoring stake intended to be driven into soft or sandy soil (10), comprising: - a longitudinal and straight body (2) whose distal end (3) is pointed (3), which body is made of a semi-rigid material, - straight lateral arms (4a, 4b, 4c, 4d) attached to the body (2) by their end (40a, 40b, 40c, 40d) closest to the tip (3) and whose other ends (41a, 41b, 41c, 41d) are free, said arms being arranged along said body and distributed over its periphery, characterized in that: - the lateral arms (4a, 4b, 4c, 4d) are at least four in number, - the body (2) and the side arms (4a, 4b, 4c, 4d) are made of biodegradable plastic, - the ratio between the initial length of the lateral arms (4a, 4b, 4c, 4d) and their initial width is between 15 and 20, - the ratio between the initial length of the lateral arms (4a, 4b, 4c, 4d) and their initial thickness is between 15 and 20.

2. Stake according to claim 1, in which, in the rest position, the arms (4) move away from the body (2) from their end (11) attached to it towards the free end (5) at an angle of at most 5°.

3. Stake according to any one of the preceding claims, wherein the point (3) has a bevel (30), which bevel defines an inclined face having a slope which is between 30° and 45°.

4. Stake according to any one of the preceding claims, wherein the free ends (41a, 41b, 41c, 41d) of the lateral arms (4a, 4b, 4c, 4d) each have a bevel, which bevel defines an inclined face having a slope which is between 5° and 20°.

5. Stake according to any one of the preceding claims, wherein the body (2) has a hook-shaped proximal end (6).

6. A stake according to any one of the preceding claims, wherein the biodegradable plastic used has a flexural modulus greater than 0.7 GPa at 20°C and 50% relative humidity and above preferably between 1.5 GPa and 2.5 GPa at 20°C and 50% relative humidity.

7. Stake according to any one of claims 1 to 6, wherein the lateral arms (4a, 4b, 4c, 4d) are arranged in pairs, each pair being located at the same level on the body (2).

8. Stake according to any one of claims 1 to 6, wherein the lateral arms (4a, 4b, 4c, 4d) are arranged in pairs, each pair being located at different levels on the body (2).

9. Stake according to any one of claims 7 or 8, wherein the lateral arms (4a, 4b) of one pair have the same length and / or the same shape as the arms (4c, 4d) of another pair.

10. Stake according to any one of claims 7 or 8, wherein the lateral arms (4a, 4b) of one pair have a length and / or shape distinct from the arms (4c, 4d) of another pair.

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