Plug for closing holes in concrete walls

TECHNICAL FIELD

The present invention relates to closing plugs for covering and concealing holes in concrete walls, said holes preferably being made by the formwork anchoring system.

PRIOR ART

Closing plugs for covering and concealing holes in concrete walls and the like are known. Said holes are usually made by the manufacturing process of said concrete walls.

Concrete walls are manufactured on site, providing a gap between two formwork panels that are arranged in such a way that they face each other. These panels are secured together by means of an anchoring system comprising transverse bolts the ends of which are threaded. Said threaded ends protrude from the formwork panels so that the corresponding nuts can be threaded, thus securing the formwork panels.

Once the panels are secured, concrete is poured into the gap which is sandwiched between the formwork panels. For the concrete not to adhere to the transverse bolts once it has set, said bolts are previously lined by placing them in a tube, preferably made of plastic, and cones or frustoconical elements, also made of plastic, are placed at the ends to facilitate supporting against the formwork. Once the concrete has set, the formwork panels, transverse bolts, and cones or frustoconical elements are disassembled. The removal of the protective tube is optional, but since this operation is fairly tedious, many times said tubes are not disassembled and remain inside the wall.

Upon disassembling the anchoring system of the formwork panels, i.e., upon disassembling the transverse bolts and cones or frustoconical elements, through holes are generated in the concrete wall. To conceal said holes, closing plugs, preferably having a frustoconical shape, are placed in said holes, which plugs are secured in the wall by means of applying an adhesive. Other means for securing said plugs are also known.

In this sense, DE202006005621 U1 describes a decorative plug for concealing a hole in a concrete wall, which hole is generated by the manufacturing process of said wall. Said plug comprises a main body made of plastic and elastic retention means, also made of plastic, which retain the plug in place inside the protective plastic tube of the hole in the concrete wall. The plug comprises a frustoconical head and a cylindrical appendage extending from said head. A decorative metallic disc is fixed at the end of the head by means of adhesive. The elastic means comprise in one embodiment a plurality of elongated ribs arranged on the appendage such that they radially protrude.

DE202008015694U1 describes a plug for closing a hole in a concrete wall, comprising a main body and conically tapering retention means. The retention means comprise a sleeve shaped body, which is partially embedded in the main body, and three hooks projecting from the sleeve shaped body, the plug being retained inside the hole by the hooks.

DISCLOSURE OF THE INVENTION

The object of the invention is to provide a plug for closing and concealing a hole in a concrete wall, as defined in the claims.

The plug of the invention comprises a main body and elastic retention means, said retention means comprising at least one hook partially embedded in the main body and partially projecting from the main body. The at least one hook is configured for cooperating with the hole in the concrete wall for retaining the plug in said hole.

Placing said plug in the hole in the concrete wall is facilitated with the plug of the invention because it is not necessary to use additional means, such as adhesives, for example, to retain the plug in place. Furthermore, the securing of said plug is also improved because the hook of the elastic means provides good securing whether the hole to be plugged comprises the protective plastic tube of the transverse bolts (securing on a plastic material) or does not comprise said tube (securing directly on the concrete). These and other advantages and features of the invention will become apparent in view of the figures and detailed description of the invention.

DESCRIPTION OF THE DRAWINGS

Figure 1A shows a perspective view of a first embodiment of the plug according to the invention.

Figure 1 B shows a side view of the plug of Figure 1 A.

Figure 1C shows a perspective view of another embodiment of the plug according to the invention.

Figure 1 D shows a side view of the plug of Figure 1 C.

Figure 1 E shows a perspective view of another embodiment of the plug according to the invention.

Figure 1 F shows a side view of the plug of Figure 1 E.

Figure 2A is a perspective view of a set of two hooks of the elastic retention means according to the invention, attached by a U-shaped retention element.

Figure 2B is an elevational view of the set of hooks of Figure 2A.

Figure 20 shows a perspective view of a set of four hooks of the elastic retention means according to the invention but attached by a circular ring retention element.

Figure 3A shows a perspective view of another embodiment of the plug according to the invention.

Figure 3B shows a side view of the plug of Figure 3A. Figure 4A shows a perspective view of another embodiment of the plug according to the invention.

Figure 4B shows a side view of the plug of Figure 4A.

Figure 5A shows a perspective view of another embodiment of the plug according to the invention.

Figure 5B shows a side view of the plug of Figure 5A.

Figure 5C shows a side view of an embodiment of the elastic retention means of the plug of Figure 5A.

Figure 5D shows a side view of another embodiment of the elastic retention means of the plug of Figure 5A.

Figure 6A shows a perspective view of another embodiment of the plug according to the invention.

Figure 6B shows a side view of the plug of Figure 6A.

Figure 6C shows a side view of the elastic retention means of the plug of Figure 6A.

Figure 6D shows a perspective view of the elastic retention means of the plug of Figure 6A.

Figure 7A shows a perspective view of another embodiment of the plug according to the invention.

Figure 7B shows a side view of the plug of Figure 7A.

Figure 7C shows a side view of the elastic retention means of the plug of Figure 7A.

Figure 8A shows a perspective view of another embodiment of the plug according to the invention. Figure 8B shows a perspective view of the elastic retention means of the plug of Figure 8A.

Figure 8C shows a side view of the plug of Figure 8A.

Figure 9A shows a perspective view of another embodiment of the plug according to the invention.

Figure 9B shows a side view of the plug of Figure 9A.

Figure 9C shows a front view of the elastic retention means of the plug of Figure 9A.

Figure 9D shows a side view of a variant of the plug of Figure 9A, wherein the hook of the retention means is arranged inclined with respect to the longitudinal axis X.

Figure 9E shows a side view of another variant of the plug of Figure 9a, wherein the retention means comprise a plurality of hooks.

Figure 10A shows a perspective view of another embodiment of the plug according to the invention.

Figure 10B shows a front view of the elastic retention means of the plug of Figure 10A.

Figure 10C shows a side view of the plug of Figure 10A.

Figure 11A shows a section view of the concrete wall with a hole and the plug of Figure 3A before being introduced in the hole to be plugged.

Figure 11 B shows a section view of the plug of Figure 3A in use, i.e. , introduced in the hole to be plugged.

DETAILED DISCLOSURE OF THE INVENTION

Figures 1 A and 1 B show a first embodiment of the plug 1 according to the invention. As shown in said figures, the plug 1 of the invention comprises a main body 2 and elastic retention means 4. According to the invention, the retention means 4 comprise at least one hook partially embedded in the main body 2 and partially projecting from the main body 2. The at least one hook is configured for cooperating with the hole 8 in the concrete wall 9 for retaining the plug 1 in place inside said hole 8. The retention means 4 can also comprise a plurality of hooks protruding at least partially from the main body 2. In the non-limiting example of Figures 1A and 1 B, for example, the retention means 4 comprise four hooks arranged as will be described in detail below.

The plug 1 in use, i.e., when the plug 1 is introduced in the hole 8 to be plugged, is aligned with the wall or concrete wall 9, thereby concealing said hole 8, as can be seen in Figure 11 B for example. Holes in concrete walls are unavoidable because most, if not all of said holes, are caused by the manufacturing process of the concrete wall 9 itself.

The plug 1 of the invention provides an easy placement of the plug 1 in the hole 8 in the concrete wall 9 to be plugged because it is not necessary to use additional means, such as adhesives, for example, for retaining the plug 1 in place. Furthermore, the securing of said plug 1 is also improved because the hook or hooks of the elastic means 4 provide very good securing whether the hole 8 to be plugged comprises the protective plastic tube of the transverse bolts (securing on plastic material) or does not comprise said tube (securing directly on concrete).

In an embodiment of the invention shown in Figures 1A and 1 B, the retention means 4 comprise a plurality of hooks, preferably four, each hook comprising a retention flange 4a forming an acute angle a with respect to a longitudinal axis X of the plug 1 , as can be seen in Figure 1 B, or in greater detail in Figure 2B. As a result of the configuration of these flanges 4a, the plug 1 of the invention is easily arranged in place because no great effort is required to insert the plug 1 inside the hole 8 to be plugged, but at the same time the flanges 4a provide good securing which lasts over time such that additional means, such as adhesive, for example, are not necessary to keep the plug of the invention in place.

The free ends of the flanges 4a of the retention means 4 are arranged at a distance d from the longitudinal axis X of the plug 1 , said distance d being greater than the radius of the hole 8 in the concrete wall 9 to be plugged, such that, in use, with the plug 1 being arranged inside the hole 8 to be plugged, and preferably aligned with the concrete wall 9, the flanges 4a are compressed inside the hole 8, as can be seen in Figure 11 B, the free ends of the flanges 4a in this case being at a compressed distance d’ from the longitudinal axis X of the plug 1 , said compressed distance d’ being less than the initial distance d. That is, the retention flanges 4a are compressed upon entering the hole 8 to be plugged, with the securing force of the plug 1 , which force is exerted by the flanges 4a against the surface of the hole 8 to be plugged, being thereby increased. The hooks of the retention means 4, independently of the inner surface of the hole 8 to be plugged, exert very good gripping pressure; therefore, independently of whether the hole 8 to be plugged comprises the protective plastic tube of the transverse bolts, necessary in the manufacturing process of the concrete wall 9, or does not comprise said tube, the flanges 4a of the hooks of the retention means 4 adapt to the surface of the hole 8 to be plugged, the plug 1 of the invention being strongly secured inside the hole 8 to be plugged, regardless of the texture of the surface of said hole 8, of plastic (in the event that the hole comprise the plastic protective tube of the transverse bolt), or of concrete (in the event that it does not comprise said plastic protective tube). In the example of Figure 11 B, the hole 8 to be plugged does not comprise the protective plastic tube; therefore, the hooks of the retention means 4, i.e. , the flanges 4a, apply pressure directly on the concrete.

If the retention means 4 of the plug 1 of the invention comprise a plurality of hooks, these hooks are arranged equidistantly around the longitudinal axis X of the plug 1. To facilitate the manufacture of the plug 1 of the invention, the retention means 4 comprise a set of at least two hooks arranged equidistantly around the longitudinal axis X of the plug 1 , preferably diametrically opposite to one another, and attached to each other by a retention element. Each hook comprises a respective retention flange 4a. In the non-limiting example of Figures 2A and 2B, the two retention flanges 4a are attached to one another by a U-shaped retention element 5. That is, at each end of the U-shaped retention element 5 extends a corresponding hook with a respective retention flange 4a, correct securing of the plug 1 inside the hole 8 to be plugged thus being assured. Part of the retention element 5 is embedded in the main body 2, preferably the central part, whereas the retention flanges 4a emerge out from the main body 2. In a variant of this embodiment, the retention means 4 comprise two sets of two hooks, each hook comprising a corresponding retention flange 4a, both sets being arranged rotated with respect to each other, preferably 90°.

The U-shaped retention element 5 of each set comprises a base 5a and two legs 5b, each one attached to a corresponding end of said base 5a, as can be seen in Figure 2B, forming a single part. Each leg 5b is part of a corresponding hook. In the example of Figure 2B, the legs 5b and the base 5a are attached perpendicularly, said legs 5b being arranged in this case parallel with the longitudinal axis X of the plug 1. However, the legs 5b can form another different angle with the base 5a, in which case the flanges 4a would continue to form the acute angle a with respect to the longitudinal axis X of the plug 1.

In the non-limiting example of Figure 2C however, the set of hooks of the retention means are arranged also equidistantly around the longitudinal axis X of the plug 1 but the hooks are attached to one another by a circular retention element 17 which is embedded in the main body 2. The circular retention element 17 may have a disc or ring shape. As shown in Figure 2C the hooks protrude from the circular ring retention element 17, the corresponding retention flanges 4a emerging out of the main body 2.

In a preferred embodiment of this example, the set of hooks of the retention means 4 comprises four hooks, each hook comprising a respective retention flange 4a, all hooks being attached to the circular retention element 17 forming two sets of diametrically opposite flanges 4a, both sets of flanges 4a being disposed rotated with respect to each other, preferably 90°.

The retention flanges 4a can form an acute angle a with respect to the longitudinal axis X of the plug, or they can be perpendicular to said longitudinal axis X, as will be described in detail further below.

The flanges 4a of hooks of the plugs of the examples of Figures 1 A, 3A and 4A can be joined altogether by the circular retention element 17 or they can be joined in sets of two flanges 4a with the U-shaped retention elements 5.

In the preferred embodiment of the invention, the main body 2 comprises a frustoconical or cylindrical head 6, the main body 2 comprising an active surface 15, in this embodiment being arranged at one end of the head 6, which in use is aligned with the uncovered face 9a of the wall or concrete wall 9, thus concealing the corresponding hole 8. In the context of the invention, the uncovered face 9a refers to the visible surface of the concrete wall 9. Said active surface 15 is preferably perpendicular to the longitudinal axis X of the plug 1. The main body 2 also comprises an auxiliary surface 16 which in use is arranged inside the hole 8 in the concrete wall 9, the retention means 4 protruding from said auxiliary surface 16.

In one embodiment of the invention, the auxiliary surface 16 is facing the active surface 15, the hooks of the retention means 4 protruding axially from the main body 2, i.e., from said auxiliary surface 16 which is the front surface of the head 6, in the insertion direction A, as shown in Figure 1A. In another embodiment of the invention, the auxiliary surface 16 is the lateral surface of the head 6, i.e the generatrix of the frustoconical or conical head 6, the hooks of the retention means 4 protruding directly radially from the main body 2, i.e., perpendicular to the longitudinal axis X, as will be described in detail below. The shape of the head 6 in the example of Figure 1A is cylindrical, whereas in the examples of Figures 1C and 1 E it is frustoconical.

In another embodiment of the invention, the main body 2’ also comprises a frustoconical or cylindrical base 7, the head 6 extending axially from the base 7 in the insertion direction A, as can be seen in Figure 3B, for example. The head 6 comprises a smaller diameter than the smallest diameter of the base 7. In this embodiment, the active surface 15 of the main body 2’, which in use is aligned with the uncovered face 9a of the concrete wall 9, is arranged at one end of the base 7. The active surface 15 is also preferably perpendicular to the longitudinal axis X of the plug T, and hooks of the retention means 4, particularly the retention flanges 4a, protrude from the auxiliary surface 16 of the head 6 as described above, namely axially from the front surface of the head 6 or from the lateral surface of the head 6. Figures 3A, 3B, 4A or 4B show examples of plugs comprising a main body 2’ comprising the head 6 and the base 7.

In these embodiments, i.e., in embodiments in which the main body 2’ comprises both the head 6 and the base 7, the retention flanges 4a can form an acute angle a with respect to the longitudinal axis X of the plug of the invention, and the retention means 4 can also comprise at least one set of two hooks arranged diametrically opposite to one another and attached to one another by a U-shaped retention element 5, preferably comprising two sets of two hooks, both sets being arranged rotated with respect to each other, preferably 90°.

These embodiments, i.e., embodiments in which the main body 2’ comprises both the head 6 and the base 7, are particularly advantageous when the hole 8 in the concrete wall 9 has a narrow frustoconical opening 8’. As the person skilled in the art knows, the protective kit of the transverse bolt of the manufacturing process of a concrete wall can comprise a central cylindrical segment (cylindrical protective tube made of plastic) to which there is added at each end a frustoconical element made of plastic which is removed once the concrete is set. The hole 8 generated in the concrete wall 9 will therefore have two frustoconical openings 8’ (made of concrete) arranged at the ends of the hole 8 between which there is arranged a cylindrical segment 8” (made of plastic if the protective tube has not been removed, or made of concrete if said protective tube has been removed), as can be seen in Figure 11 A. Usually only one of the frustoconical openings 8’ of the hole 8, the opening 8’ arranged in the exposed face 9a of the concrete wall 9, is plugged, such that in the description reference will only be made to a hole 8 in which the opening 8’ is arranged in the exposed face 9a of the concrete wall 9. However, if both openings are to be plugged, the same will be done at both ends of the hole 8. Figures 11A and 11 B depict a hole 8 with a frustoconical opening 8’ (the second opening being omitted) to better understand the invention. Depending on the shape of the frustoconical opening 8’ of the hole 8 to be plugged, it will be appropriate to use one plug (without the base 7) or the other (with the base 7) to assure better securing of the plug. For example, in the event that the frustoconical segment of the opening 8’ of the hole 8 is narrow (not very deep), it is advisable to use the plugs 100, 101 , 110, 111 , 120, 121 , 122, 122’, 122” or 123 comprising the main body 2’ with the base 7 (according to any of its variants). Otherwise, i.e., if the frustoconical segment of the opening 8’ of the hole 8 to be plugged is deep enough, both plug 1 , T or 1” comprising the main body 2 without the base 7 and plugs 100, 101 , 110, 111 , 120, 121 , 122, 122’, 122” or 123 which comprising the base 7, could be used.

In these embodiments, i.e., embodiments in which the main body 2’ comprises both the head 6 and the base 7, the base 7 can be adjusted to the shape of the frustoconical opening 8’ of the hole 8 such that when said base 7 abuts with the bottom of the frustoconical opening 8’, the active surface 15 of the main body 2’ is aligned with the exposed face 9a of the concrete wall 9.

Furthermore, in this embodiment in which the main body 2’ comprises the head 6 and the body 7, said head 6 and said body 7 form a single part.

Figures 5A and 5B show another embodiment of the plug 110 of the invention, in which the only thing that changes with respect to the described plugs are the elastic retention means 4. In this case, the main body 2’ comprises both the head 6 and the base 7 and the retention means 4 comprise a single hook comprising a single conical-shaped retention flange 4a, as can be seen for example in Figure 5C, and a mast 10. The retention flange 4a is attached to the mast 10 which is arranged on the geometric axis of the retention flange 4a, part of said mast 10 being embedded in the main body 2’, such that said mast 10 is arranged parallel to or aligned with the longitudinal axis X, the hook protruding axially from the main body 2’ in the insertion direction A. The mast 10 can be a rod or a rod with a helical embedded portion, for example. As can be seen in Figure 5C, the retention means 4 of this embodiment resemble an open umbrella, the retention flange 4a forming an acute angle a with respect to the longitudinal axis X of the plug. For the purpose of improving adherence of the mast 10 in the main body 2’, said mast 10 can comprise at the end farthest away from the vertex 11 of the hook a stop 12 which is arranged preferably perpendicular to the mast 10, as can be seen in Figure 5D, or a helical portion, thus improving the grip between the mast 10 and the main body 2’.

Another variant of the plug 120 of the invention shown in Figures 7A, 7B and 7C differs from the plug 110 described above in the shape of the retention means 4. The retention means 4 of this variant also comprise a single hook with a single retention flange 4a, but in this case it is circular. The retention flange 4 can be arranged perpendicular to the longitudinal axis X or tilted with respect to said longitudinal axis X. Said retention flange 4a is also attached to a mast 10 arranged on its geometric axis, part of said mast 10 being embedded in the main body 2’, such that said mast 10 is arranged parallel to or aligned with the longitudinal axis X, the hook of the retention means 4 protruding axially from the main body 2’ in the insertion direction A. The mast 10 can be a rod or a rod with a helical embedded portion, as in the example before. When the plug 120 is introduced in the hole 8 to be plugged, the retention flange 4a is bent, the retention flange 4a being compressed inside the hole 8 to be plugged such that it exerts continuous pressure against the inner surface of the hole 8.

To facilitate the bending of the circular retention flange 4a, the latter can optionally comprise at least one notch 14 arranged at the distal end of the retention flange 4a, said notch 14 preferably extending in a radial direction of said circular retention flange 4a. In the example of the plug 121 of Figures 8A, 8B and 8C, the circular retention flange 4a comprises a plurality of radial notches 14 distributed uniformly along the peripheral circumference of the retention flange 4a.

Another variant of the plug 111 of the invention, shown in Figures 6A and 6B, differs from the plugs 110, 120 and 121 described above in the shape of the retention means 4. The retention means 4 of this variant also comprise a single hook comprising a single retention flange 4a, but in this case, in the form of a frustoconical ring, such that it forms a perimetral skirt. The hook also comprises a support 13 in the form of a circular ring or a circular disc shape. The end having a smaller dimension of the retention flange 4a is attached to the support 13, at least part of said support 13 being embedded in the main body 2’. Said support 13 is arranged transverse to the longitudinal axis X such that the hook protrude radially from the main body 2’, preferably from the head 6 of the main body 2’, as can be seen in Figure 6B. In a variant, the embedded portion of the hook is fixed to a rod or a helical bolt, not shown in the drawings, said rod or helical bolt being also embedded in the main body 2’. The rod or helical bolt embedded in the main body 2’ is preferably arranged in the longitudinal direction of the main body 2’.

As shown in Figure 6B or 6C, the retention flange 4a forms an acute angle a with respect to the longitudinal axis X of the plug. Furthermore, the free end of the retention flange 4a is still arranged at distance d from the longitudinal axis X of the plug 111 , as can be seen in Figure 6B, said distance d being greater than the radius of the hole 8 in the concrete wall 9 to be plugged.

Another variant of the plug 122 of the invention, shown in Figures 9A and 9B and 9C, differs from the plug 111 described above in the shape of the retention means 4. The retention means 4 of this variant also comprise a single hook with a single retention flange 4a, but in this case in the form of an annulus , as can be seen in Figure 9C, or a disc, the annulus or the disc protruding radially from the main body 2’ of the plug 122, preferably from the head 6, such that the retention flange 4a is arranged perpendicular to the longitudinal axis X of the plug 122. The free end of the retention flange 4a is still arranged at distance d from the longitudinal axis X of the plug 122, as can be seen in Figure 9B, said distance d being greater than the radius of the hole 8 in the concrete wall 9 to be plugged. In a variant shown in Figure 9D, the annulus or disc of the retention means 4 of the plug 122’ is arranged tilted with respect to said longitudinal axis X instead of being arranged perpendicular to the longitudinal axis X.

In this embodiment, it is not necessary for the retention means 4 to comprise an additional support to allow the attachment to the main body 2’ because part of the annulus, preferably the part having a smaller diameter, or disc is embedded in the main body 2’, as can be seen in Figure 9A. When the plug 122 is introduced in the hole 8 to be plugged, the retention flange 4a is bent, the retention flange 4a being compressed inside the hole 8 to be plugged, such that it exerts continuous pressure against the inner surface of the hole 8.

To facilitate the bending of the retention flange 4a in the form of an annulus, it can optionally also comprise at least one notch 14 arranged at the distal end of the retention flange 4a. In the example of the plug 123 of Figures 10A and 10B, the retention flange 4a comprises a plurality of radial notches 14 distributed uniformly along the peripheral circumference of the retention flange 4a. The notches 14 extend radially, as can be seen in Figure 10B. In the embodiments of Figures 1C to 1 F, the main body 2 of the plugs T and 1” does not comprise the base 7, and the head 6, which is frustoconical in this case, is longer than the head 6 of the plug 1 of Figure 1A (which does comprise the base 7). These plugs T and 1” are suitable for being used when the hole 8 generated in the concrete wall 9 is conical or frustoconical along the entire length thereof.

Unlike the embodiment of the plug 1 of Figure 1A (which does not comprise the base 7) in which the retention means 4 protrude axially from the main body 2, in the plugs T and 1” of Figures 1C to 1 F the retention means 4 protrude from the main body 2 according to a direction perpendicular to the longitudinal axis X.

The retention means 4 of the plug T of the embodiment of Figures 1C and 1 D comprise a single hook comprising a single retention flange 4a in the form of a frustoconical ring, such that it forms a perimetral skirt, as described for the plug 111 of Figure 6A. The hook also comprises a support 13 in the form of a circular ring or a circular disc. The end having a smaller dimension of the retention flange 4a is attached to the support 13, at least part of said support 13 being embedded in the main body 2’. The support 13 is arranged transverse to the longitudinal axis X, the retention means 4 protruding from the main body 2 according to a direction perpendicular to the longitudinal axis X, as can be seen in Figure 1 D. In this case, the retention flange 4a forms an acute angle a with respect to the longitudinal axis X of the plug and the free end of the retention flange 4a is still arranged at distance d from the longitudinal axis X of the plug T, said distance d being greater than the radius of the hole 8 in the concrete wall 9 to be plugged.

Optionally, the embedded portion of the support 13 of the hook can be fixed to a rod or a helical bolt, not shown in the drawings, said rod or helical bolt being also embedded in the main body 2. The rod or helical bolt embedded in the main body 2 is preferably arranged in the longitudinal direction of the main body 2.

The retention means 4 of the plug 1 ” of the embodiment of Figures 1 E and 1 F differs from the plug T described above in the shape of the retention means 4. As in the case of the plug 122 of Figure 9A, the retention means also comprise a single hook comprising a retention flange 4a, but in this case in the form of an annulus, as can be seen in Figure 1 F, or a disc, part of the annulus or the disc being embedded in the main body 2 and part of the annulus or disc protruding from the head 6 of the main body 2 according to a direction perpendicular to the longitudinal axis X of the plug 1”, the retention flange 4a being arranged perpendicular to the longitudinal axis X of the plug 1” in this case. The free end of the retention flange 4a is still arranged at distance d from the longitudinal axis X of the plug 1”, as can be seen in Figure 1 F, said distance d being greater than the radius of the hole 8 in the concrete wall 9 to be plugged. Optionally, the embedded portion of the annulus or disc of the hook can be fixed to a rod or a helical bolt, not shown in the drawings, said rod or helical bolt being also embedded in the main body 2. The rod or helical bolt embedded in the main body 2 is preferably arranged in the longitudinal direction of the main body 2.

In a variant not shown in the drawings, the annulus or disc is arranged inclined with respect to said longitudinal axis X instead of being arranged perpendicular to the longitudinal axis X. When the plug 1” is introduced in the hole 8 to be plugged, the retention flange 4a is bent, the retention flange 4a being compressed inside the hole 8 to be plugged, such that it exerts continuous pressure against the inner surface of the hole 8.

To facilitate the bending of the retention flange 4a in the form of an annulus or a disc, it can optionally also comprise the notches 14 described above.

Optionally, in other variants of the embodiments comprising a hook comprising a single retention flange 4a protruding from the head 6 according to a direction perpendicular to the longitudinal axis X, whether or not they comprise the notches 14, or are arranged perpendicular or tilted with respect to said longitudinal axis X, the retention means 4 can comprise more than one hook, the retention flanges 4a of each hook being spaced apart from one another according to the direction of the longitudinal axis X. The free ends of the retention flanges 4a of the plurality of hooks can be arranged at the same distance d with respect to the longitudinal axis X, or said distance d can be decreased as the retention flanges 4a approach the free end of the head 6 of the corresponding plug according to the insertion direction A. An example of these variants is shown in Figure 9E.

In Figure 9E, which corresponds with a plug 122” of the type having a main body 2’ which comprises both the head 6 and the base 7, the retention means 4 comprise three hooks, each hook comprising a retention flange 4a in the form of an annulus or disc shape, and in this case, protruding radially from the head 6. The retention flanges 4a are arranged parallel and spaced apart from one another according to the direction of the longitudinal axis X. In this example, the free ends of all the retention flanges 4a are arranged at the same distance d with respect to the longitudinal axis X.

The head 6 of the main body comprises a length L, such that the hook or hooks protruding from the lateral surface of the head 6 according to any of the embodiments described, are placed axially within said length L. With this configuration the plug of the invention is more robust and reliable since a void core in the retention means 4 is avoided, i.e. cantilever hooks are avoided, which can weaken the plug over time.

Figure 11 B shows a section view of the plug 100 of the embodiment of Figures 3A and 3B (embodiment in which the main body 2’ comprises the base 7) introduced in the hole 8 to be plugged. As shown in said figure, the retention flanges 4a are compressed and exert continuous pressure against the inner surface of the hole 8 (in this case, against the inner surface of the cylindrical segment 8”), which pressure lasts over time. The shape of the retention flanges 4a before and after introducing the plug 100 in the hole 8 to be plugged can be seen in Figures 11 A and 11 B. As shown in Figure 11 B, the base 7 (according to any of its variants) is arranged inside the cylindrical segment 8” of the hole 8 in the concrete wall 9. In this case, the distance d of the retention flanges 4a with respect to the longitudinal axis X of the plug 100 before introducing the plug 100 in the hole 8 is greater than the radius of the cylindrical segment 8” of the hole 8 in the concrete wall 9. If the plug of the invention is retained in the frustoconical opening 8’ of the hole 8 by the retention flanges 4a, for example of the plug 1 of the embodiment without the base 7, then the distance d of the retention flanges 4a with respect to the longitudinal axis X of the plug 1 before introducing said plug 1 in the hole 8 is greater than the radius of an annular portion of the frustoconical opening 8’, which portion corresponds with the position of the plug 1 in which it is aligned with the concrete wall 9.

According to any of the described embodiments, the elastic means 4 of the plug of the invention and the main body 2 or 2’ are made of different materials, the elastic means 4 being made of a first material and the main body 2 or 2’ of a second material. The first material is a plastic or metallic material, preferably stainless steel, and the second material is fiber cement, preferably similar in texture and color to the material of the concrete wall 9 containing the hole 8 to be plugged.